ACL Study Group survey reveals the evolution of anterior cruciate ligament reconstruction graft choice over the past three decades

One type of graft for reconstruction of the ACL does not suit all patients based on their characteristics and sports: a scoping review

The selection of graft type for anterior cruciate ligament reconstruction remains a topic of debate, taking into consideration patient characteristics, as well as the type and level of sports involvement. The aim of this scoping review was to investigate patient characteristics that might influence the selection of graft type for anterior cruciate ligament reconstruction. PubMed and Scopus were searched to identify articles for inclusion. All included studies focused on one or more patient characteristics involved in the decision-making process regarding anterior cruciate ligament reconstruction autograft, including the hamstrings tendon (HT), patellar tendon (BPTB) and quadriceps tendon (QT). Out of the 1,977 initial studies, 27 studies were included in this review. The BPTB graft seems to be the preferred choice in young patients, females, and athletes-especially those engaged in pivoting sports. The HT graft seems to be the preferred choice in less active and older patients, along with those involved in sports where knee extensors are vital. The HT graft is not preferable in patients with a small body height and graft diameter. Moreover, surgeon preferences were also of importance for graft selection. The success of a specific graft type in anterior cruciate ligament reconstruction is highly dependent on the patient's characteristics and type of sport. Patient characteristics such as age, gender, body height, graft diameter, and the patient's activity level should all be considered when choosing the appropriate graft type.

Knee flexor strength at 6 months after anterior cruciate ligament reconstruction using hamstring tendon can be predicted from that at 3 months

PURPOSE

This study aimed to identify factors influencing persistent muscle weakness in knee flexor strength after anterior cruciate ligament (ACL) reconstruction using the hamstring tendon and establish a clear cut-off value at 3 months postoperatively for the limb symmetry index (LSI) to exceed 90% at 6 months postoperatively.

METHODS

One hundred forty-eight patients undergoing ACL reconstruction were included and categorised into two groups based on knee flexor strength at 6 months postoperatively: patients with LSI of 90% or greater (achieved group: n = 114) and patients with LSI less than 85% (nonachieved group: n = 34). Items with significant differences between the two groups (preoperative waiting period, LSI to body weight ratio of knee flexor and extensor strength at 3 months postoperatively and peak torque angle of knee flexor muscle) were included in the multiple logistic regression analysis. Additionally, a receiver operating characteristic curve was used to calculate the cut-off value of the LSI at 3 months postoperatively, which was required to achieve the LSI criteria for knee flexor strength 6 months postoperatively.

RESULTS

Multiple logistic regression analysis extracted the preoperative waiting period and LSI for knee flexor strength at 3 months postoperatively. The cut-off value at 3 months postoperatively was 76.9% (area under the curve value, 0.82; sensitivity, 0.76; and specificity, 0.81) of the LSI.

CONCLUSION

The LSI of at least 76.9% for knee flexor strength at 3 months after ACL reconstruction was an indicator for achieving the 6 months postoperatively. This is a criterion to aim for, considering the stress on the graft and the regeneration process of the semitendinosus tendon.

LEVEL OF EVIDENCE

Level III.

Combining a digital health application with standard care significantly enhances rehabilitation outcomes for ACL surgery patients

INTRODUCTION

Anterior cruciate ligament (ACL) rupture is one of the most common sports injuries. Regardless of the surgical treatment, patients require intensive education about the pathology, therapeutic options and physical therapy. However, it is often not possible for the patient to start physical therapy directly and schedule adequate consultations. Digital health applications are medical devices that can help bridge the gap between physiotherapy sessions and provide qualified, convenient and effective education and treatment. This study is needed to explore alternative methods to ensure continuous and effective rehabilitation for ACL patients who face delays in accessing traditional physiotherapy. The study aimed to compare app-assisted therapy plus standard of care (conventional orthopaedic and physiotherapeutic measures) versus isolated standard of care for patients with planned ACL surgery.

METHODS

A monocentric, two-arm, 1:1 randomized controlled study examined 80 patients after a cruciate ligament rupture with or without meniscal injury. Patients over 18 years with a confirmed diagnosis of ACL rupture and planned surgical reconstruction using autologous grafts were included. The study criteria additionally included willingness to use the Orthopy app and sufficient German language proficiency. The study excluded patients with severe concomitant injuries, prior knee surgeries, chronic pain conditions and those not compatible with app usage. Patients were randomized and their baseline data (t0) was collected. Subsequently, they received their treatment according to their treatment group. The study included a presurgery period (2-6 weeks) and a postsurgery period (14 weeks). Interim assessments were done via online questionnaires at t1 (if more than 3 weeks before surgery) and t3, t4 and t5 (postsurgery). Additional clinical assessments were conducted at t2 (presurgery) and t6 (14 weeks postsurgery). Primary outcome measures included the knee injury and osteoarthritis outcome score (KOOS), with subjective pain and function levels (numeric rating scale [NRS]) as secondary endpoints.

RESULTS

The clinical trial was able to show positive outcomes on the KOOS Pain and Symptoms subscale of the primary endpoint KOOS in the interventional group compared to the standard of care group. A statistically significant pain reduction could be seen at t1 (p = 0.0005), t2 (p = 0.0068) and t4 (approximately 6 weeks after surgery; p = 0.01). A significant reduction of symptoms at t1 (p = 0.0001), t2 (p = 0.0036) and t6 (p = 0.0377) were recognized. These findings are further supported by the significant benefit of the pain NRS at t4 and positive tendencies at t3, t5 and t6. The KOOS subscales quality of life (p = 0.0066), activities of daily living (p = 0.0009) and Sport (p = 0.0484) showed significant effects before surgery.

CONCLUSION

The Orthopy app is a medical device that is both safe and effective for use. Combining the Orthopy app and standard of care can significantly improve prehabilitation and rehabilitation in surgical treatment with ACL reconstruction compared with the isolated standard of care.

LEVEL OF EVIDENCE

Level I.

Quadriceps tendon size does not affect postoperative strength recovery following quadriceps tendon anterior cruciate ligament reconstruction

OBJECTIVE

The influence of quadriceps tendon (QT) size on postoperative quadriceps strength following QT anterior cruciate ligament reconstruction (ACLR) is unclear. Therefore, this study aimed to determine the relationship between QT morphology and postoperative quadriceps strength recovery following primary ACLR using a QT autograft.

METHODS

Patients who underwent primary ACLR using QT autograft from 2014 to 2022 followed by a postoperative isometric strength measurement between 5 and 8 months were retrospectively reviewed. Using preoperative magnetic resonance imaging findings, the anterior-posterior (A-P) thickness, medial-lateral (M-L) width, and cross-sectional area (CSA) of the QT were measured. Postoperative residual CSA of QT was estimated based on the graft-harvest diameter. The quadriceps index (QI) was also calculated, which was determined by dividing the maximum isometric quadriceps torque on the involved side by the maximum quadriceps torque on the uninvolved side. Associations between the QI and QT morphology were assessed. Furthermore, multivariable logistic regression analysis with the addition of sex as a covariate was performed with the addition of each individual measure of QT morphology to determine the association with a QI ​≥80%.

RESULTS

A total of 84 patients (mean age: 21.9 ​± ​7.3 years; 46 female) were included. Residual CSA showed a statistically significant positive correlation with the QI (r ​= ​0.221, p ​= ​0.043). There were no statistically significant correlations between QI and CSA, A-P thickness, or M-L width. Multivariable logistic analysis adjusting for sex demonstrated that each individual measure of QT morphology was not statistically significantly associated with a QI ​≥80%.

CONCLUSION

A statistically significant correlation between measures of preoperative QT size and postoperative quadriceps strength were not detected in patients undergoing primary QT autograft ACLR. A smaller residual QT CSA based on QT harvest diameter was weakly associated with decreased quadriceps strength 5-8 months postoperatively, but this association was not independent of sex. Future studies examining the impact of QT morphology on quadriceps strength at longer follow-up intervals are needed.

LEVEL OF EVIDENCE

IV.

Ultrasound-Guided Posteromedial Semitendinosus Tendon Harvest

Hamstring tendon autografts have emerged as the graft of choice by over 50% of sports surgeons worldwide performing anterior cruciate ligament reconstruction. A more recent technique in harvesting the semitendinosus tendon, the posteromedial approach, afforded multiple benefits compared with the anteromedial approach. However, for the inexperienced surgeon, the current techniques may not be as simple because of decreased tendon tension after general anesthesia induction and subcutaneous layer dissection, making it difficult to palpate the semitendinosus tendon. By utilizing ultrasound to assist us during our harvest, we can perform the procedure with increased accuracy and efficiency, which leads to a safer, more proficient, and less invasive procedure.

Sex-Specific Outcomes After Anterior Cruciate Ligament Reconstruction Using an All-Soft Tissue Quadriceps Tendon Autograft in a Young Active Population

BACKGROUND

The ideal graft for anterior cruciate ligament (ACL) reconstruction (ACLR) in young athletes has a high return-to-sport (RTS) rate and a low reinjury rate. Quadriceps tendon autografts are being used with increasing frequency for ACLR in this population, despite a paucity of evidence to support their use.

PURPOSE

To report the RTS rate, ipsilateral reinjury rate, and contralateral ACL injury rate in a young athletic population undergoing primary ACLR using an all-soft tissue quadriceps tendon (ASTQT) autograft.

STUDY DESIGN

Cases series; Level of evidence, 4.

METHODS

Patients aged 14 to 22 years who underwent primary ACLR using an ASTQT autograft by a single surgeon between January 1, 2005, and April 30, 2020, were identified via electronic medical records and contacted ≥24 months after ACLR to complete a survey regarding subsequent ipsilateral or contralateral ACL injuries and RTS. Patients who had undergone previous ACLR (ipsilateral or contralateral) were excluded.

RESULTS

A total of 656 patients (330 male, 326 female; mean age, 17.9 years) were identified, and 395 patients completed the survey (60.2%; 174 male, 221 female; mean age, 17.8 years) with a mean follow-up of 73 ± 29 months (range, 24-139 months). The RTS rate was high (male: 87.7%; female: 82.8%; P = .19). Male and female patients had similar rates of revision ACLR (male: 12.6%; female: 10.0%; P = .40) and contralateral ACL injuries (male: 13.8%; female: 11.3%; P = .46).

CONCLUSION

A high RTS rate and similar rates of ipsilateral and contralateral ACL injuries were found for male and female patients in a young athletic population undergoing primary ACLR using an ASTQT autograft. These results help one to better understand the utility of ASTQT grafts to support successful ACLR in young athletic populations, for which ASTQT grafts appear to yield favorable outcomes.

Quadriceps tendon versus hamstring tendon graft for primary anterior cruciate ligament reconstruction: A systematic review and meta-analysis of randomised trials

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) is most commonly performed with hamstring tendon (HT) or bone-patellar tendon-bone (BTB) autografts, although the quadriceps tendon (QT) autograft has recently increased in popularity. This systematic review and meta-analysis review compares QT and HT autografts for primary ACLR with a sole focus on randomised controlled trials (RCTs).

METHODS

A prospective protocol was registered on PROSPERO (CRD42023427339). The search included MEDLINE, Embase and Web of Science until February 2024. Only comparative RCTs were included. The primary outcome was the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form score. Secondary outcomes included: other validated patient-reported outcome measures (PROMs), objective strength scores, complications, and return to sport and work.

RESULTS

From 2,609 articles identified, seven were included (n = 474 patients). This meta-analysis did not identify a significant difference in post-operative IKDC scores (5 articles; p = 0.73), Lysholm scores (3 studies; p = 0.80) or Tegner activity scales (2 studies; p = 0.98). There were no differences in graft failure rates (4 studies; p = 0.92) or in overall adverse events (4 studies; p = 0.83) at 24 months post-ACLR as per meta-analysis. Donor site morbidity scores were significantly lower in the QT group (MD -4.67, 95% CI -9.29 to -0.05; 2 studies, 211 patients; p = 0.05, I2 = 34%).

CONCLUSION

There were no differences between QT and HT in PROMs, graft failure rates or overall complications based on low- to moderate-quality evidence. There may possibly be lower donor site morbidity with the QT autograft, however, the evidence is not sufficient to draw definitive conclusions.

Diameter of Quadrupled Semitendinosus Autograft in Primary Anterior Cruciate Ligament Reconstruction Did Not Impact Early Revision Rate or Functional Outcome in a Large Cohort of Patients

PURPOSE

To determine whether the diameter of the quadrupled semitendinosus tendon (ST) graft in primary anterior cruciate ligament reconstruction (ACLR) is related to the risk of revision ACLR within 2 years of primary ACLR, postoperative knee laxity, and patient-reported knee outcome. Furthermore, to investigate whether smaller graft than estimated is related to revision ACLR.

METHODS

Patients who underwent primary ACLR with a quadrupled ST autograft at our institution from January 2005 to December 2017 were identified. Data from the Swedish National Knee Ligament Registry were collected up to 2 years or until revision surgery was registered within 2 years after primary ACLR. Knee laxity was assessed preoperatively and at 6-month follow-up using the KT-1000 arthrometer (134 N anterior tibial load). The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and at 2 years postoperatively from Swedish National Knee Ligament Registry. On the basis of anthropometric measurements (body height and weight) and sex, the estimated quadrupled ST graft diameter was calculated.

RESULTS

A total of 4,519 patients who underwent ACLR with a quadrupled ST autograft were included. The mean graft diameter was 8.3 ± 0.7 mm; 8.0 ± 0.6 mm for women and 8.6 ± 0.7 mm for men. The quadrupled ST graft diameter was not significantly correlated to revision ACLR. There was no significant difference in the ST graft diameter regarding postoperative knee laxity. The correlations between ST graft diameter and KOOS were weak, except for the "sport and recreation" subscale (P = .012).

CONCLUSIONS

The quadrupled ST graft diameter was not significantly related to the need for early revision ACLR, nor was it related to postoperative knee laxity or patient-reported outcome except for the KOOS "sport and recreation" subscale. Smaller ST graft than estimated was not a risk factor for revision ACLR.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

The prognosis of iatrogenic saphenous nerve injuries during hamstring tendon harvesting in anterior cruciate ligament reconstruction

PURPOSE

This study aims to evaluate the long-term outcomes of saphenous nerve (SN) injuries from hamstring tendon harvesting during ACL reconstruction, focusing on clinical results and patient satisfaction after at least two years. Additionally, it investigates the incidence, recovery patterns, and impact of these injuries on functional outcomes, daily activities, and ACL re-rupture rates immediately post-surgery and at final follow-up.

MATERIALS AND METHODS

A retrospective review was conducted on patients who had undergone ACL reconstruction with hamstring tendon grafts at a single institution between January 2015 and January 2020. The incidence of SN injuries was assessed immediately after surgery and at final follow-up. Additionally, the recovery rate and time were evaluated, and the impact of these injuries on functional outcomes was measured using the Lysholm Knee Score (LKS) and patient-reported effects on daily activities.

RESULTS

Of the 159 patients analyzed, iatrogenic SN injuries were initially observed in 87 (54.7%) patients post-ACLR. By the final follow-up, paresthesia had resolved in 36 (22.6%) patients within an average of 11.1 months. Persistent SN injuries were recorded in 51 (32.1%) patients, affecting various extents of the infrapatellar branch (IPBSN) and the sartorial branch (SBSN) of the saphenous nerve. Patients with persistent SN injuries experienced a significant impact on daily activities and had lower LKS scores compared to those without injuries or with recovered injuries. Furthermore, a higher re-rupture rate was associated with persistent SN injuries.

CONCLUSIONS

The study finds that SN injuries during hamstring graft harvesting for ACL reconstruction are common, with a significant portion of patients experiencing persistent sensory deficits for at least two years postoperatively. These injuries are observed to adversely affect patient satisfaction and functional outcomes and to increase the re-rupture rate.

Risk factors for anteroposterior laxity increase over time in double-bundle anterior cruciate ligament reconstruction using hamstring autografts

PURPOSE

An anteroposterior (AP) laxity can increase over time after anterior cruciate ligament reconstruction (ACLR) using hamstring tendons; however, the associated risk factors remain unclear. This study aimed to investigate the risk factors of this phenomenon.

METHODS

Overall, 151 patients who underwent ACLR using hamstring autografts were recruited. AP laxity was evaluated using Knee Lax 3 arthrometer at 5 months, 1 and 2 years postsurgery. Patients were categorised into groups I (>1 mm increase) and C (<1 mm increase) based on whether they experienced an irreversible increase in AP laxity after 1 or 2 years compared with 5 months. Patient demographics and Knee injury and Osteoarthritis Outcome Score (KOOS) at 2 years postsurgery were compared between groups.

RESULTS

Group I (n = 33, 21%) showed a side-to-side difference of 4.6 (3.0-7.2) mm in AP laxity preoperatively and 0.3 (-0.7 to 1.3), 1.1 (0.2-1.9) and 2.4 (1.7-3.2) mm at 5 months, 1 and 2 years postoperatively, while group C (n = 119, 79%) showed 4.3 (2.8-5.7) mm preoperatively and 1.3 (0-1.9), 0.9 (0.1-1.8) and 0.6 (-0.3 to 1.5) mm, respectively. No significant differences were observed in the overall KOOS at 2 years (n.s.). However, group I was older (36 [22-46] vs. 28 [19-39] years; p = 0.044), had longer surgical waiting periods (122 [69-341] vs. 81 [52-136] days; p = 0.041) and lower preoperative Tegner activity scale scores (6 [5-7] vs. 7 [6,7]; p = 0.002).

CONCLUSION

While 33 patients (21%) experienced AP laxity increase over time, they had comparable clinical outcomes with group C.

LEVEL OF EVIDENCE

Level III.

Sequential Comparison of Knee Muscle Strength after Anterior Cruciate Ligament Reconstruction between Hamstring Autograft and Tibialis Anterior Allograft: Propensity Score Matched Pair Analysis

Among the graft options for anterior cruciate ligament reconstruction (ACLR), hamstring autografts are widely regarded as the preferred choice for primary ACLR among orthopedic surgeons worldwide. However, concerns persist regarding postoperative knee flexor weakness. We aimed to compare knee extensor and flexor strengths between hamstring autograft and tibialis anterior allograft groups in ACLR patients, who were propensity score-matched based on baseline characteristics. A retrospective analysis included 58 matched pairs who underwent isokinetic strength tests at 6 and 12 months post operation. Isokinetic muscle strength tests found no significant difference in knee extensor and flexor strength at 6 months post operation between the hamstring autograft and tibial anterior allograft groups. At 12 months, the hamstring autograft group exhibited significantly greater knee flexor deficit (total work and average power) compared to the allograft group, despite no differences in extensor strength or patient-reported outcomes. This study highlights the impact of hamstring autograft harvesting on muscle strength and recovery following ACLR in short-term period.

Surgical Techniques in Primary ACL Reconstruction: Getting It Right the First Time

The ideal anterior cruciate ligament reconstruction (ACLR) is an individualized anatomic approach aimed at restoring the native structure and function of the knee. Surgeons are tasked with difficult decisions during operative planning, including the optimal graft choice for the patient and appropriate anatomic tunnel placement. Special considerations should additionally be given for skeletally immature patients and those at high-risk for failure, including younger, active patients participating in pivoting sports. The purpose of this review is to provide an overview of the individualized approach to ACLR, including the necessary preoperative and operative considerations to optimize patient outcomes.

ChatGPT Provides Unsatisfactory Responses to Frequently Asked Questions Regarding Anterior Cruciate Ligament Reconstruction

PURPOSE

To determine whether the free online artificial intelligence platform ChatGPT could accurately, adequately, and appropriately answer questions regarding anterior cruciate ligament (ACL) reconstruction surgery.

METHODS

A list of 10 questions about ACL surgery was created based on a review of frequently asked questions that appeared on websites of various orthopaedic institutions. Each question was separately entered into ChatGPT (version 3.5), and responses were recorded, scored, and graded independently by 3 authors. The reading level of the ChatGPT response was calculated using the WordCalc software package, and readability was assessed using the Flesch-Kincaid grade level, Simple Measure of Gobbledygook index, Coleman-Liau index, Gunning fog index, and automated readability index.

RESULTS

Of the 10 frequently asked questions entered into ChatGPT, 6 were deemed as unsatisfactory and requiring substantial clarification; 1, as adequate and requiring moderate clarification; 1, as adequate and requiring minor clarification; and 2, as satisfactory and requiring minimal clarification. The mean DISCERN score was 41 (inter-rater reliability, 0.721), indicating the responses to the questions were average. According to the readability assessments, a full understanding of the ChatGPT responses required 13.4 years of education, which corresponds to the reading level of a college sophomore.

CONCLUSIONS

Most of the ChatGPT-generated responses were outdated and failed to provide an adequate foundation for patients' understanding regarding their injury and treatment options. The reading level required to understand the responses was too advanced for some patients, leading to potential misunderstanding and misinterpretation of information. ChatGPT lacks the ability to differentiate and prioritize information that is presented to patients.

CLINICAL RELEVANCE

Recognizing the shortcomings in artificial intelligence platforms may equip surgeons to better set expectations and provide support for patients considering and preparing for ACL reconstruction.

Comparative effectiveness of peroneus longus tendon (PLT) autografts versus hamstring tendon (HT) autografts in anterior cruciate ligament reconstruction: a comprehensive systematic review and meta analysis

The hamstring tendon (HT) autograft is currently the most widely utilised autograft option for anterior cruciate ligament (ACL) reconstruction. However, recent studies endorse the peroneus longus tendon (PLT) autograft as a viable alternative. To evaluate this, we systematically reviewed randomised controlled trials (RCTs) to compare the efficacy of PLT against HT autografts. Our search encompassed Cochrane, Embase, OVID, PubMed, and Scopus databases for RCTs comparing outcomes of PLT and HT autografts in ACL reconstruction. Primary outcomes included Lysholm and International Knee Documentation Committee (IKDC) scores, while secondary outcomes involved American Orthopaedic Foot and Ankle Society (AOFAS) scores, graft diameters and donor-site complications. Statistical analysis was performed using Review Manager 5.4 (Cochrane Collaboration) and heterogeneity was assessed with I2 statistics. 683 patients from 6 RCTs were included, with 338 (49.5%) patients treated with PLT autografts. Follow-up ranged from 12 to 30 months. Despite lower preoperative Lysholm scores in the PLT group, no significant differences were observed at 6 and 12 months. Although preoperative and 6-month IKDC scores were lower in the PLT group, no significant differences were found at 12 and 24 months. AOFAS scores showed no significant preoperative difference, but slightly lower scores were noted in the PLT group at 12 or 24 months. There was no significant difference in graft diameter, while donor-site complications were fewer in the PLT group. In summary, the PLT autograft is a promising and non-inferior alternative to the HT autograft, demonstrating equivalent outcomes in patient-reported knee and ankle metrics, comparable graft diameters and fewer donor-site complications.

The Biomechanical, Biochemical, and Morphological Properties of 19 Human Cadaveric Lower Limb Tendons and Ligaments: An Open-Access Data Set

BACKGROUND

Methodological heterogeneity hinders data comparisons across isolated studies of tendon and ligament properties, limiting clinical understanding and affecting the development and evaluation of replacement materials.

PURPOSE

To create an open-access data set on the morphological, biomechanical, and biochemical properties of clinically important tendons and ligaments of the lower limb, using consistent methodologies, to enable direct tendon/ligament comparisons.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Nineteen distinct lower limb tendons and ligaments were retrieved from 8 fresh-frozen human cadavers (5 male, 3 female; aged 49-65 years) including Achilles, tibialis posterior, tibialis anterior, fibularis (peroneus) longus, fibularis (peroneus) brevis, flexor hallucis longus, extensor hallucis longus, plantaris, flexor digitorum longus, quadriceps, patellar, semitendinosus, and gracilis tendons; anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments; and 10 mm-wide grafts from the contralateral quadriceps and patellar tendons. Outcomes included morphology (tissue length, ultrasound-quantified cross-sectional area [CSAUS], and major and minor axes), biomechanics (failure load, ultimate tensile strength [UTS], failure strain, and elastic modulus), and biochemistry (sulfated glycosaminoglycan [sGAG] and hydroxyproline contents). Tissue differences were analyzed using mixed-model regression.

RESULTS

There was a range of similarities and differences between tendons and ligaments across outcomes. A key finding relating to potential graft tissue suitability was the comparable failure loads, UTS, CSAUS, sGAG, and hydroxyproline present between hamstring tendons (a standard graft source) and 5 tendons not typically used for grafting: fibularis (peroneus) longus and brevis, flexor and extensor hallucis longus, and flexor digitorum longus tendons.

CONCLUSION

This study of lower limb tendons and ligaments has enabled direct comparison of morphological, biomechanical, and biochemical human tissue properties-key factors in the selection of suitable graft tissues. This analysis has identified 6 potential new donor tissues with properties comparable to currently used grafts.

CLINICAL RELEVANCE

This extensive data set reduces the need to utilize data from incompatible sources, which may aid surgical decisions (eg, evidence to expand the range of tendons considered suitable for use as grafts) and may provide congruent design inputs for new biomaterials and computational models. The complete data set has been provided to facilitate further investigations, with the capacity to expand the resource to include additional outcomes and tissues.

Single bundle hamstrings autograft preparation techniques for anterior cruciate ligament reconstruction: current concepts

Anterior cruciate ligament reconstruction (ACLR) is one of the most common orthopedic procedures, and huge variation exists in the surgical technique. Single bundle hamstrings autograft reconstruction is a common method and has good clinical outcomes. A criticism of the hamstrings autograft is a small graft diameter, often less than 8-mm, which has been associated with increased re-rupture rates. Several graft preparation techniques for single bundle hamstrings autograft exist. Perioperative decisions include the number of tendons utilized, number of graft strands, graft configuration, and femoral and tibial fixation methods. Awareness of the minimum tendon and graft length required to produce each graft variation is necessary to avoid common pitfalls. However, intraoperative graft modification is possible to maximize graft diameter, and obtain proper fixation. The objective of this current concepts review is to describe the indications, surgical anatomy, technique, intraoperative tips, clinical outcomes, and complications for single bundle hamstrings autograft preparation techniques in ACLR.

ACL Reconstruction Using Quadrupled Semitendinosus Versus Double-Stranded Semitendinosus and Gracilis Autograft: 2-Year Results From a Prospective Randomized Controlled Study

BACKGROUND

A disadvantage of using hamstring tendon autograft consisting of the semitendinosus and gracilis tendons for anterior cruciate ligament reconstruction is pain from tendon harvesting and persistent hamstring weakness. In the tendon-sparing all-inside technique, a quadrupled semitendinosus graft and adjustable-loop cortical fixation are suggested to give less postoperative flexion deficits while displaying overall similar clinical results to the traditional hamstring technique. However, there are a limited number of high-quality studies comparing these techniques with inconsistent results.

PURPOSE

To investigate differences between the all-inside (quadrupled semitendinosus) and traditional hamstring (double-stranded semitendinosus and gracilis) technique regarding (1) self-reported function, (2) hamstring strength, and (3) knee laxity.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

A total of 98 patients were randomized to either the all-inside or the traditional hamstring technique. Perioperatively, duration of surgery and graft size were obtained. The International Knee Documentation Committee 2000 Subjective Knee Form score, Knee injury and Osteoarthritis Outcome Score, Tegner Activity Scale score, knee laxity (KT-1000 arthrometer side-to-side difference and pivot shift), range of motion, isokinetic knee strength, and hop test score were collected preoperatively and 2 years postoperatively. Return-to-sport readiness was evaluated 9 months postoperatively.

RESULTS

A total of 89 patients completed 2-year follow-up, 45 patients with the all-inside technique and 44 patients with the traditional hamstring technique. There were no significant differences between groups in any of the outcome measures 2 years after surgery, but there was a tendency in the all-inside group toward having increased anterior translation (mean, 3.6 mm vs 2.7 mm), a higher number of revision surgeries (5 patients vs 2 patients), and more patients having +1 and +2 pivot-shift values (29 vs 18 patients) when compared with the traditional group.

CONCLUSION

The all-inside technique yields equivalent results to the traditional hamstring technique 2 years after surgery and should be considered a reliable technique to use for ACL reconstruction. Sparing the gracilis tendon does not lead to less persistent hamstring weakness. Long-term follow-up is needed to further determine whether the tendency of increased anterior translation seen at 2 years postoperatively will lead to a higher risk of graft failure.

Rehabilitation and Return to Sport After Anterior Cruciate Ligament Reconstruction

Rehabilitation after an anterior cruciate ligament (ACL) reconstruction requires patience, devotion, and discipline. Rehabilitation should be individualized to each patient's specific need and sport. Return to sport is a continuum throughout the rehabilitation, and patients should not return to performance before passing a battery of muscle function tests and patient-reported outcomes, as well as change of direction-specific tests. Return to full participation should be an agreement between the patient, physical therapist, surgeon, and coach. For minimal risk for second ACL injury, patients should continue with maintenance and prevention training even after returning to sport.

Patellofemoral joint cartilage lesions frequently develop shortly after anterior cruciate ligament reconstruction using hamstring tendon autograft: A systematic review

PURPOSE

This study aimed to investigate the development of patellofemoral joint (PFJ) cartilage lesions following anterior cruciate ligament reconstruction (ACLR) using hamstring tendon (HT) autograft through a systematic review.

METHODS

A comprehensive search was conducted in PubMed, Embase, Cochrane Library and Google Scholar databases to find articles published from database inception until 15 November 2023. The search terms were [('Anterior Cruciate Ligament' [mesh] OR 'anterior cruciate ligament' OR 'ACL') AND 'reconstruction' AND 'cartilage' AND ('second look arthroscopy' OR 'second-look arthroscopy' OR 'MRI' OR 'magnetic resonance imaging')]. Inclusion criteria were studies that reported on the occurrence of PFJ cartilage lesions following ACLR using HT autograft, as determined by second-look arthroscopy or follow-up magnetic resonance imaging (MRI).

RESULTS

Fifteen studies (1084 patients) met the inclusion criteria, with follow-up periods ranging from 1 to 5 years. In the results of second-look arthroscopy, cartilage grade deterioration was observed, ranging from MDs of 0.1 to 2.0 in the patella and from 0 to 1.0 in the trochlea. Follow-up MRI results reported the incidence of PFJ cartilage degeneration with rates ranging from 20% to 44%. Patient-reported outcome measures often showed no significant association with PFJ cartilage lesions. The studies included in this review reported various risk factors for cartilage lesion development.

CONCLUSION

Cartilage lesions in the PFJ, detected using second-look arthroscopy or follow-up MRI, frequently develop shortly after ACLR using HT autograft. At this stage, patients might not show specific symptoms; however, those with risk factors require careful observation and evaluation by clinicians during follow-up.

LEVEL OF EVIDENCE

Level IV.

Relationship between hamstring strength and hop performance at 8 and 12 months after ACL reconstruction with hamstring tendon autografts

BACKGROUND

The relationship between hamstring strength and hop performance after anterior cruciate ligament (ACL) reconstruction with hamstring tendon (HT) autografts has not been well elucidated. The aim was to investigate the relationship between eccentric hamstring strength, assessed with the NordBord, and concentric hamstring strength, assessed with the Biodex, with hop performance at 8 and 12 months after ACL reconstruction.

METHODS

Registry study. Patients ≥ 16 years who had undergone primary ACL reconstruction with HT autograft, followed by muscle strength and hop tests at 8 and 12 months were included. Correlations of the relative hamstring strength (Nm/kg or N/kg) and limb symmetry index (LSI) with hop performance were analyzed. Pearson's correlation coefficient, and coefficient of determination (r2) were used for statistical analysis.

RESULTS

A total of 90 patients were included, of which 48 (53%) were women. The mean age at ACL reconstruction was 27.0 ± 8.0 years. Relative hamstring strength had significant positive correlations with hop performance, ranging from r = 0.25-0.66, whereas hamstring strength LSI had significant positive correlations which ranged from r = 0.22-0.37 at 8 and 12 months after ACL reconstruction. At 12 months, the relative hamstring strength in the Biodex explained 32.5-43.6% of the hop performance in vertical hop height, hop for distance relative to height, and the total number of side hops, whereas the relative hamstring strength in the NordBord explained 15.2-23.0% of the hop performance.

CONCLUSION

The relative hamstring strength in the Biodex test explained 32.5-43.6% of the hop performance, whereas the relative hamstring strength in the NordBord explained 15.2-23.0%. Thus, our findings suggest that relative hamstring strength, especially in the hip-flexed position may be a better indicator of hop performance at 8 and 12 months after ACL reconstruction in patients treated with HT autograft.

Revision ACL reconstruction in female athletes: current concepts

The challenge of revision anterior cruciate ligament (ACL) reconstruction lies in its complexity, varied presentation, and technical intricacies. A successful ACL reconstruction should allow patients to safely return to preinjury activities. However, it is only sometimes simple, and many risk factors and concurrent pathologies come into play. Evaluating and analysing the cause of failure and associated conditions is paramount to addressing them effectively. Despite a plethora of research and improvements in knowledge and technology, e gaps exist in issues such as optimal techniques of revision surgery, graft options, fixation, concurrent procedures, rehabilitation and protocol for return to sports of high-level athletes. Female athletes need additional focus since they are at higher risk of re-injury, suboptimal clinical outcomes, and lower rates of return to sport following revision reconstruction. Our understanding about injury prevention and the protection of ACL grafts in female athletes needs to be improved. This review focuses on the current state of revision ACL surgery in female athletes and provides recommendations and future directions for optimising outcomes in this high-risk group.

Comparison of the retear rate 2years after ACL reconstruction with the Tape Locking Screw short graft system and the STG technique: A case control study with propensity score matching

PURPOSE

Theoretically, short semitendinosus grafts result in less pain and morbidity while providing greater knee flexion strength and sparing the gracilis tendon. They often require the use of blind bone tunnels as well as fixation at both ends of the graft with suspensory cortical buttons. The "Tape Locking Screw" (TLS) system is another option. There are few studies comparing ACL reconstruction with a short graft using the 4-strand semitendinosus graft (ST4-TLS) technique with that of the semitendinosus-gracilis (STG) procedure. This study was designed: (1) to compare the retear rate following these two technics after 2years of follow-up, (2) to compare the clinical scores, complications and return to sport times between the two procedures Q1, Q2.

HYPOTHESIS

Our hypothesis was that there would be no differences in retear rates between the two techniques.

METHODS

This single center case control study included 290 patients who underwent STG reconstruction that were paired by propensity score matching to 299 patients who underwent ST4-TLS reconstruction. The main evaluation criterion was the retear rate 2years after surgery. Secondary criteria were the two-year postoperative complication rate, the time to return to sport, to pivot sports and to running, as well as the complication rates and clinical scores 6months, 1year and 2years after surgery.

RESULTS

At the final follow-up, the overall retear rate in our series of ACL ligament reconstruction was 6.0% (36/596). There was no difference in retear rates between the groups 2years after ligament reconstruction [ST4-TLS: 6.7% (20/299) vs. STG: 5.4% (16/297); p=0.47]. The postoperative KOOS symptom score and the Tegner score were found to be better in the STG group at 1year (81 vs. 78, p=0.008) and 2years (5.64 vs. 5.10, p=0.016), respectively, representing the minimally clinically important difference (MCID) for the latter. No difference was found in the other clinical scores 6months, 1year or 2years after surgery. There was no significant difference in the return to sport [TLS: 93.0% (164/299) vs. STG: 93.0% (158/297) p=0.99] or the complication rate [TLS: 8.7% (26/299) vs. STG: 7.4% (22/297) p=0.89] between the groups.

DISCUSSION

The ST4-TLS ACL ligament reconstruction technique was found to be as reliable as the standard STG procedure 2years after surgery for the retear rate and the return to sport, although the results of certain postoperative clinical scores seem to be lower.

LEVEL OF EVIDENCE

III; case control study.

Bone-patellar tendon-bone autograft is associated with a higher rate of return to preinjury levels of performance in high-level athletes than anterior cruciate ligament reconstruction using hamstring autograft

PURPOSE

Return to preinjury levels of performance (RTP) is the main goal after anterior cruciate ligament reconstruction (ACL-R) for athletes when ACL graft rupture is a career-threatening event. The purpose of this study was to elucidate the associated factors for RTP and subsequent ACL injury after ACL-R using bone-patellar tendon-bone (BPTB) or hamstring (HT) autograft in high-level athletes with a minimum postoperative follow-up of 24 months.

METHODS

This retrospective study included 157 patients who had preinjury Tegner activity level of 9 and underwent primary ACL-R using BPTB (average age, 16.9 years; 35 males and 36 females) or HT (average age, 17.2 years; 49 males and 37 females). The mean follow-ups were 33.6 months in BPTB and 44.5 months in HT, respectively. The data were obtained based on routine clinical follow-ups and telephone interviews performed by the surgeon. Multivariate logistic regression analysis was conducted to determine the association of patient variables with RTP and subsequent ACL injury.

RESULTS

Ninety-nine patients (63.1%) were able to RTP. The rate of RTP in BPTB (74.6%) was significantly higher than that of HT (53.5%) (p < 0.05). The overall average timing of RTP after ACL-R was 10.0 months while that was significantly earlier in BPTB (9.7 months) than in HT (10.5 months) (p < 0.05). Twenty-three (14.6%) and 21 patients (13.4%) had ACL graft ruptures and ACL injuries in the contralateral knees, respectively. Multivariate analyses showed that BPTB (odds ratio [OR], 2.590; 95% confidence interval [CI], 1.300-5.160; p = 0.007) was associated with a higher potential for RTP after ACL-R. The incidence of ACL graft rupture after ACL-R decreased with BPTB (OR, 0.861; 95% CI, 0.770-0.962; p = 0.009).

CONCLUSIONS

The use of BPTB autograft was associated with a higher rate of RTP and a lower incidence of ACL graft rupture compared to ACL-R using HT autograft.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Postoperative Strength Differences at Short-Term Follow-Up Vary Based on Autograft Harvest Site After Adolescent Transphyseal Anterior Cruciate Ligament Reconstruction

PURPOSE

To compare the clinical and patient-reported outcomes of adolescent patients who underwent anterior cruciate ligament reconstruction (ACLR) with quadriceps tendon (QT) versus hamstring tendon (HT) autograft.

METHODS

This was a retrospective cohort study of adolescent patients aged 18 years or younger treated at a single tertiary care children's hospital who underwent primary transphyseal ACLR using QT or HT between January 2018 and December 2019. All patients had minimum 6-month follow-up. Outcomes included isokinetic strength testing, postoperative Patient-Reported Outcomes Measurement Information System and International Knee Documentation Committee scores, and complications; these were compared between the QT and HT cohorts.

RESULTS

A total of 84 patients (44 HT and 40 QT patients) were included. The QT cohort had a higher proportion of male patients (62.5% vs 34.1%, P = .01). At 3 months, HT patients had a lower hamstring-quadriceps (H/Q) strength ratio (60.7 ± 11.0 vs 79.5 ± 18.6, P < .01) and lower Limb Symmetry Index in flexion (85.6 ± 16.1 vs 95.5 ± 15.7, P = .01) whereas QT patients had a lower Limb Symmetry Index in extension (67.3 ± 9.5 vs 77.4 ± 10.7, P < .01). The H/Q ratio at 6 months was lower in HT patients (59.4 ± 11.5 vs 66.2 ± 7.5, P < .01). Patient-Reported Outcomes Measurement Information System and International Knee Documentation Committee scores were not different at 3 months or latest follow-up. QT patients had more wound issues (20.0% vs 2.3%, P = .01). Patients receiving HT autograft had more ipsilateral knee injuries (18.2% vs 2.5%, P = .03), but there was no difference in graft failure for ACLR using HT versus QT (9.1% vs 2.5%, P = .36).

CONCLUSIONS

There were no differences in patient-reported outcome measures between patients receiving QT autografts and those receiving HT autografts. Patients with QT grafts had more postoperative wound issues but a lower rate of ipsilateral knee complications (graft failure or meniscal tear). Differences in quadriceps and hamstring strength postoperatively compared with the contralateral limb were observed for adolescent ACLR patients receiving QT and HT autografts, respectively. This contributed to higher H/Q ratios seen at 3 and 6 months postoperatively for patients receiving QT autografts.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic study.

Recruitment and baseline characteristics of young adults at risk of early-onset knee osteoarthritis after ACL reconstruction in the SUPER-Knee trial

Objectives

The study aims to (1) report the process of recruiting young adults into a secondary knee osteoarthritis prevention randomised controlled trial (RCT) after anterior cruciate ligament reconstruction (ACLR); (2) determine the number of individuals needed to be screened to include one participant (NNS) and (3) report baseline characteristics of randomised participants.

Methods

The SUpervised exercise-therapy and Patient Education Rehabilitation (SUPER)-Knee RCT compares SUPER and minimal intervention for young adults (aged 18-40 years) with ongoing symptoms (ie, mean score of <80/100 from four Knee injury and Osteoarthritis Outcome Score subscales (KOOS4)) 9-36 months post-ACLR. The NNS was calculated as the number of prospective participants screened to enrol one person. At baseline, participants provided medical history, completed questionnaires (demographic, injury/surgery, rehabilitation characteristics) and underwent physical examination.

Results

1044 individuals were screened to identify 567 eligible people, from which 184 participants (63% male) enrolled. The sample of enrolled participants was multicultural (29% born outside Australia; 2% Indigenous Australians). The NNS was 5.7. For randomised participants, mean±SD age was 30±6 years. The mean body mass index was 27.3±5.2 kg/m2, with overweight (43%) and obesity (21%) common. Participants were, on average, 2.3 years post-ACLR. Over half completed <8 months of postoperative rehabilitation, with 56% having concurrent injury/surgery to meniscus and/or cartilage. The most affected KOOS (0=worst, 100=best) subscale was quality of life (mean 43.7±19.1).

Conclusion

Young adults post-ACLR were willing to participate in a secondary osteoarthritis prevention trial. Sample size calculations should be multiplied by at least 5.7 to provide an estimate of the NNS. The SUPER-Knee cohort is ideally positioned to monitor and intervene in the early development and trajectory of osteoarthritis.

Trial registration number

ACTRN12620001164987.

Increased risk for early revision with quadriceps graft compared with patellar tendon graft in primary ACL reconstructions

PURPOSE

Bone patella-tendon bone (BPTB) and hamstring tendon (HT) autografts are the most used grafts in primary anterior cruciate ligament (ACL) reconstructions (ACLR) in Norway. Quadriceps tendon (QT) autograft has gained more popularity during the past years. The purpose of this study is to compare revision rates and patient-reported outcomes of primary QT with BPTB and HT autograft ACL reconstructions in Norway at 2-year follow-up. It was hypothesized that there would be no difference in 2-year revision rates between all three autografts.

METHODS

Data included primary ACLR without concomitant ligament surgeries, registered in the Norwegian Knee Ligament Register from 2004 through 2021. Revision rates at 2 years were calculated using Kaplan-Meier analysis. Hazard ratios (HR) for revision were estimated using multivariable Cox regression analysis with revision within 2 years as endpoint. Mean change in patient-reported outcome was recorded preoperatively and at 2 years through the Knee Injury and Osteoarthritis Outcome Score (KOOS) subcategories 'Sport' and 'Quality of Life' was measured for patients that were not revised and analysed with multiple linear regression.

RESULTS

A total of 24,790 primary ACLRs were identified, 10,924 with BPTB, 13,263 with HT and 603 with a QT graft. Patients in the QT group were younger (23.5 years), more of them were women (58.2%) and over 50% had surgery <3 months after injury. The QT group had the highest prevalence of meniscal injuries (61.9%). Revision estimates at 2-years were 3.6%, 2.5% and 1.2% for QT, HT and BPTB, respectively (p < 0.001). In a Cox regression analysis with QT as reference, BPTB had a lower risk of revision (HR 0.4, 95% Cl 0.2-0.7, p < 0.001). No significant difference was observed in the revision risk between QT and HT (HR 1.1, 95% Cl 0.7-1.8, n.s.). The two most common reported reasons for revision were: traumatic graft rupture and nontraumatic graft failure. There were no differences between the groups in change of KOOS in subcategories 'Sport' and 'Quality of Life' at 2-years follow-up.

CONCLUSION

The 2-year risk of revision after ACLR with QT was higher than BPTB and similar to HT. No difference was found between the groups in patient-reported outcomes. This study provides valuable insights for both surgeons and patients when making decisions about the choice of autografts in primary ACL reconstructions.

LEVEL OF EVIDENCE

Level II.

Risk of Revision and Reoperation After Quadriceps Tendon Autograft ACL Reconstruction Compared With Patellar Tendon and Hamstring Autografts in a US Cohort of 21,973 Patients

BACKGROUND

The use of quadriceps tendon (QT) autografts has increased in the past 10 years. However, there remains a dearth of large studies examining the effects of graft selection on anterior cruciate ligament reconstruction (ACLR) that includes QT grafts.

PURPOSE

To evaluate the risk of subsequent surgical outcomes, including revision and reoperation, for a large cohort of patients with primary ACLR according to autograft selection.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Data from a US health care system ACLR registry were used to conduct a cohort study. Primary isolated autograft ACLRs were identified (2012-2021). The exposure of interest was autograft type: QT, bone-patellar tendon-bone (BPTB), and hamstring tendon (HT). Multivariable Cox regression models were used to evaluate the risk of aseptic revision (defined as a subsequent surgery where removal and replacement of the original graft for noninfectious reasons was required) and risk of aseptic reoperation (defined as any subsequent surgery for noninfectious reasons where the graft was left intact) according to autograft selection.

RESULTS

The study sample comprised 21,973 ACLRs performed by 290 surgeons at 53 hospitals. QT, BPTB, and HT autografts were used in 1103 (5.0%), 9519 (43.3%), and 11,351 (51.7%) ACLRs, respectively. In adjusted models, no significant differences were observed in revision risk (hazard ratio [HR], 1.06; 95% CI, 0.60-1.89; P = .837) or reoperation risk (HR, 1.00; 95% CI, 0.70-1.43; P = .993) within 4 years of follow-up when comparing QT ACLR with BPTB ACLR. Additionally, no differences in 4-year revision (HR, 0.62; 95% CI, 0.34-1.12; P = .111) or reoperation (HR, 1.24; 95% CI, 0.85-1.80; P = .262) risks were observed when comparing QT ACLR with HT ACLR. HT ACLRs were noted to have a higher risk of revision (HR, 1.52; 95% CI, 1.25-1.84; P < .001) compared with BPTB ACLRs but a lower risk of reoperation (HR, 0.86; 95% CI, 0.75-0.98; P = .024).

CONCLUSION

In this large multicenter study using data from an ACLR registry, the authors found no difference in the risk of revision or reoperation when QT was compared with BPTB or HT autograft with the numbers available, but they did find a 1.5 times higher risk of revision when HT autograft was compared with BPTB autograft. Surgeons may use this information when choosing the appropriate graft for ACLR in their patients.

The NordBord test reveals persistent knee flexor strength asymmetry when assessed two and five years after ACL reconstruction with hamstring tendon autograft

OBJECTIVE

Comparison of knee flexor strength limb symmetry index (LSI) between the NordBord-test and the Biodex-test, and to determine the relationship between knee flexor strength and function in patients 2 and 5 years after anterior cruciate ligament reconstruction (ACL-R) with hamstring tendon (HT) autografts.

DESIGN

Observational registry study.

SETTING

Primary care.

PATIENTS

Cross-sectional data from 96 patients (55% women) participating in a rehabilitation-registry after ACL-R with HT autografts.

MAIN OUTCOME MEASURES

Comparison of knee flexor strength symmetry between the Biodex-test and the NordBord-test. Secondly, the relationship between knee flexor strength test and perceived knee function, activity level, and hop performance.

RESULTS

The NordBord-test demonstrated greater strength deficits compared to the Biodex-test with a mean difference of 12.5% ± 15.1% 95 % CI [8.1; 16.9%] at 2 years, and 11.1% ± 11.9% 95 % CI [7.7; 14.6 %] at 5 years after ACL-R. Relative concentric knee flexor strength (Nm/kg) in the Biodex demonstrated significant weak-to-moderate correlations with activity level and hop performance (r = 0.33-0.67) at 2 and 5 years.

CONCLUSION

The NordBord-test identified deficits in knee flexor strength LSI not seen with the Biodex-test at 2 and 5 years after ACL-R. No significant correlations were found between the persistent knee flexor strength asymmetry and perceived function, activity level or hop performance.

Plastic and elastic biomechanical properties of anterior cruciate ligament autografts

BACKGROUND

Anterior cruciate ligament (ACL) rupture is a common orthopedic injury, occurring in roughly 68.6 per 100,000 persons annually, with the primary treatment option being ACL reconstruction. However, debate remains about the appropriate graft type for restoring the native biomechanical properties of the knee. Furthermore, plastic graft elongation may promote increased knee laxity and instability without rupture. This study aims to investigate the plastic properties of common ACL-R graft options.

METHODS

Patellar tendon (PT), hamstring tendon (HT), and quadriceps tendon (QT) grafts were harvested from 11 cadaveric knees (6 male and 5 female) with a mean age of 71(range 55-81). All grafts were mechanically tested under uniaxial tension until failure to determine each graft's elastic and plastic biomechanical properties.

RESULTS

Mechanically, the QT graft was the weakest, exhibiting the lowest failure force and the lowest failure stress (QT < HT, p = 0.032). The PT was the stiffest of the grafts, having a significantly higher stiffness (PT > QT, p = 0.0002) and Young's modulus (PT > QT, p = 0.001; PT > HT, p = 0.041). The HT graft had the highest plastic elongation at 4.01 ± 1.32 mm (HT > PT, p = 0.002). The post-yield behavior of the HT tendon shows increased energy storage capabilities with the highest plastic energy storage (HT > QT, p = 0.012) and the highest toughness (HT > QT, p = 0.032).

CONCLUSION

Our study agrees with prior studies indicating that the failure load of all grafts is above the requirements for everyday activities. However, grafts may be susceptible to yielding before failure during daily activities. This may result in the eventual loss of functionality for the neo-ACL, resulting in increased knee laxity and instability.

Preferences in anterior cruciate ligament reconstruction: A survey among orthopedic surgeons in China

The purpose of this study was to reveal the current trends and preferences of Chinese orthopedic surgeons regarding anterior cruciate ligament (ACL) reconstruction through a nationwide web-based survey conducted in China. The survey questionnaire was distributed via WeChat to the chairmen of provincial orthopedic and sports medicine organizing committees in China, who then shared it in their respective WeChat workgroups. The questionnaire consisted of 52 multiple-choice questions covering 8 sections. Data collection was implemented by Questionnaire Star. A total of 812 valid questionnaires were returned: 94.21% of the respondents preferred single-bundle reconstruction of ACL, while 61.70% preferred autogenous semitendinosus plus gracilis reconstruction; 76.35% of the respondents preferred establishing the femoral tunnel first, while 47.29% preferred establishing the femoral tunnel through a medial auxiliary approach; and 85.10% of the respondents recommended patients to undergo surgery within 3 months after ligament injury. Besides, the vast majority of respondents chose to retain the ligamentous remnant bundle (92.98%) and recommended routine use of knee braces postoperatively (94.09%). It is recommended to perform arthroscopic single-bundle ACL reconstruction with the remnant preserving technique using a hamstring autograft within 3 months of ACL rupture, with support of postoperative functional braces.

Comparison of knee flexor strength recovery between semitendinosus alone versus semitendinosus with gracilis autograft for ACL reconstruction: a systematic review and meta-analysis

BACKGROUND

Whether there is a difference in harvesting the semitendinosus tendon alone (S) or in combination with the gracilis tendon (SG) for the recovery of knee flexor strength after anterior cruciate ligament (ACL) reconstruction remains inconclusive. Therefore, this study aimed to assess the recovery of knee flexor strength based on the autograft composition, S or SG autograft at 6, 12, and ≥ 24 months after ACL reconstruction.

METHODS

A systematic review and meta-analysis was conducted following the PRISMA guidelines. A comprehensive search was performed encompassing the Cochrane Library, Embase, Medline, PEDRo and AMED databases from inception to January 2023. Inclusion criteria were human clinical trials published in English, comprised of randomized controlled trials (RCTs), longitudinal cohort-, cross-sectional and case-control studies that compared knee flexor strength recovery between S and SG autografts in patients undergoing primary ACL reconstruction. Isokinetic peak torques were summarized for angular velocities of 60°/s, 180°/s, and across all angular velocities, assessed at 6, 12, and ≥ 24 months after ACL reconstruction. A random-effects model was used with standardized mean differences and 95% confidence intervals. Risk of bias was assessed with the RoBANS for non-randomized studies and the Cochrane RoB 2 tool for RCTs. Certainty of evidence was appraised using the GRADE working group methodology.

RESULTS

Among the 1,227 patients from the 15 included studies, 604 patients received treatment with S autograft (49%), and 623 received SG autograft (51%). Patients treated with S autograft displayed lesser strength deficits at 6 months across all angular velocities d = -0.25, (95% CI -0.40; -0.10, p = 0.001). Beyond 6 months after ACL reconstruction, no significant difference was observed between autograft compositions.

CONCLUSION

The harvest of S autograft for ACL reconstruction yields superior knee flexor strength recovery compared to SG autograft 6 months after ACL reconstruction, irrespective of angular velocity at isokinetic testing. However, the clinical significance of the observed difference in knee flexor strength between autograft compositions at 6 months is questionable, given the very low certainty of evidence and small effect size. There was no significant difference in knee flexor strength recovery between autograft compositions beyond 6 months after ACL reconstruction.

TRIAL REGISTRATION

CRD42022286773.

Strength symmetry after autograft anterior cruciate ligament reconstruction

OBJECTIVE

To compare postoperative isometric quadriceps strength indices (QI%) and hamstring strength limb symmetry indices (HI%) between partial thickness quadriceps tendon (pQT), full thickness quadriceps tendon (fQT), and bone-patellar-tendon bone (BPTB) autograft anterior cruciate ligament reconstruction (ACLR).

METHODS

Patients with primary ACLR with pQT, fQT, or BPTB autograft with the documentation of quantitative postoperative strength assessments between 2016 and 2021 were included. Isometric Biodex data, including QI% and HI% (calculated as the percentage of involved to uninvolved limb strength) were collected between 5 and 8 months and between 9 and 15 months postoperatively.

RESULTS

In total, 124 and 51 patients had 5-8- and 9-15-month follow-up strength data, respectively. No significant difference was detected between groups for sex. However, patients undergoing fQT were found to be older than those undergoing BPTB (24.6±7 vs 20.2±5; ​p = 0.01). There were no significant differences in the number of concomitant meniscus repairs between the groups (pQT vs. fQT vs. BPTB). No significant differences were detected in median (min-max) QI% between pQT, fQT, and BPTB 5-8 months [87 ​% (44%-130 ​%), 84 ​% (44%-110 ​%), 82 ​% (37%-110 ​%) or 9-15 months [89 ​% (50%-110 ​%), 89 ​% (67%-110 ​%), and 90 ​% (74%-140 ​%)] postoperatively. Similarly, no differences were detected in median HI% between the groups 5-8 months or 9-15 months postoperatively.

CONCLUSION

The study was unable to detect differences in the recovery of quadriceps strength between patients undergoing ACLR with pQT, fQT, and BPTB autografts at 5-8 months and 9-15-months postoperatively.

LEVEL OF EVIDENCE

III.

Outcomes of bone-patellar tendon-bone autograft and quadriceps tendon autograft for ACL reconstruction in an all-female soccer player cohort with mean 4.8-year follow up

OBJECTIVE

The purpose is to compare functional outcomes, return to soccer rates, and revision rates in an all-female soccer player cohort undergoing quadriceps tendon (QT) autograft ACLR versus bone-patellar tendon-bone (BPTB) autograft ACLR.

METHODS

Female soccer players who sustained an ACL rupture and underwent primary anatomic, single-bundle ACLR with BPTB autograft or QT autograft were included. Demographic and surgical characteristics were collected. Outcomes of interest included Tegner score, International Knee Documentation Committee (IKDC) score, Marx score, return to soccer rates, and failure rates.

RESULTS

Data on 23 patients undergoing BPTB autograft ACLR and 14 undergoing QT autograft ACLR was available. Average age was 18.7 years, and average follow up was 4.8 years. Overall, 76 ​% (28/37) returned to soccer and 5.4 ​% (2/37) underwent revision ACLR. No major significant differences were found in demographic or surgical characteristics. No differences were found in postoperative IKDC scores, preoperative, postoperative, or change from pre-to postoperative Marx activity scores, or pre-and postoperative Tegner scores between the groups. QT autograft ACLR patients had significantly less change in Tegner scores pre-to postoperatively compared to the BTPB autograft ACLR group (0.6 ​± ​1.2 versus 2.1 ​± ​1.8; p ​= ​0.02). Both groups had similar rates of return to soccer [78 ​% (18/23) BPTB autograft ACLR versus 71 ​% (10/14) QT autograft ACLR; p ​= ​0.64] and rates of revision (8.7 % (2/23) BPTB autograft ACLR; 0 % (0/14) QT autograft ACLR.

CONCLUSION

Results of this study suggest that BPTB autograft ACLR and QT autograft ACLR produce comparable, successful functional and return to soccer outcomes in this all-female soccer player cohort study. Larger, prospective studies are needed to improve the strength of conclusions and provide more information on the optimal graft choice for female soccer players. Surgeons can use the results of this study to counsel female soccer players on expected outcomes after ACLR.

LEVEL OF EVIDENCE

III.

The Influence of Platelet-Rich Fibrin on the Healing of Bone Defects after Harvesting Bone-Patellar Tendon-Bone Grafts

Background and Objectives: A bone-patellar tendon-bone (BTB) autograft in anterior cruciate ligament reconstruction (ACLR) is still considered the gold standard among many orthopedic surgeons, despite anterior knee pain and kneeling pain being associated with bone defects at the harvest site. Bioregenerative products could be used to treat these defects, perhaps improving both the postoperative discomfort and the overall reconstruction. Materials and methods: During a year-long period, 40 patients were enrolled in a pilot study and divided into a study group, in which bone defects were filled with Vivostat® PRF (platelet-rich fibrin), and a standard group, in which bone defects were not filled. The main outcome was a decrease in the height and width of the bone defects, as determined by magnetic resonance imaging on the control exams during the one-year follow-up. The secondary outcomes included an evaluation of kneeling pain, measured with a visual analog scale (VAS), and an evaluation of the subjective knee scores. Results: The application of Vivostat® PRF resulted in a more statistically significant reduction in the width of the defect compared with that of the standard group, especially at 8 and 12 months post operation (p < 0.05). Eight months following the surgery, the study group's anterior knee pain intensity during kneeling was statistically considerably lower than that of the standard group (p < 0.05), and the statistical difference was even more obvious (p < 0.01) at the last follow-up. Each control examination saw a significant decrease in pain intensity in both the groups, with the values at each exam being lower than those from the prior exam (p < 0.01). A comparison of subjective functional test results 12 months post operation with the preoperative ones did not prove a statistically significant difference between the groups. Conclusions: The use of Vivostat® PRF reduces kneeling pain and accelerates the narrowing of bone defects after ACLR with a BTB graft, but without confirmation of its influence on the subjective knee score.

Editorial Commentary: Quadriceps Tendon Anterior Cruciate Ligament Graft Shows Advantages and Disadvantages

A quadriceps tendon autograft is becoming an increasingly popular graft option for both primary and revision ACL reconstruction. The biomechanical properties of a QT autograft are favorable compared to a bone-patellar tendon-bone (BPTB) or a doubled hamstring (HS) autograft. A QT autograft is associated with less donor site morbidity, such as anterior knee pain and difficulty with kneeling, than a BPTB autograft, and short-term studies have shown comparable clinical results when compared to a BPTB or a HS autograft. However, if harvested with a bone block, a QT autograft carries a higher risk of patellar fracture than a BPTB autograft. Other potential disadvantages include persistent quadriceps weakness, and registry data have shown a higher revision rate compared to a BPTB or HS ACL reconstruction, which is thought to be due to a high learning curve, leading to higher revision rates in low volume centers. Finally, a graft-fixation construct with good time 0 biomechanical characteristics may only be successful in the long term if the graft heals effectively. Time will tell.

Suture Augmentation of a Four-Strand Semitendinosus Graft Improves Time-Zero Biomechanical Properties

PURPOSE

To compare the time-zero biomechanical properties of hamstring graft preparations with or without suture augmentation for anterior cruciate ligament reconstruction (ACLR) in a full-construct cadaveric model.

METHODS

Hamstring grafts were harvested from 24 fresh frozen human cadavers and prepared in 1 of 3 ways: quadrupled SemiTendinosus (SemiT), and quadrupled SemiT with suture augmentation (SemiT+2.0-mm tape or SemiT+1.3-mm tape; n = 8 per group). Adjustable loop suspensory implants and cortical buttons were used for fixation on a porcine tibia and acrylic block. Testing included force-controlled cyclic loading at 250 N and 400 N followed by load to failure.

RESULTS

The 2 suture augmentation groups had less total elongation and increased stiffness compared to the nonsuture-augmented group (P = .025). The SemiT+2.0-mm tape group had 36% less total elongation and 34% increased stiffness compared to SemiT+1.3mm tape (P < .001).

CONCLUSIONS

Suture augmentation improves construct biomechanics at time zero following hamstring tendon ACLR. Augmentation with 2.0-mm tape suture improves construct biomechanics compared to 1.3-mm tape suture.

CLINICAL RELEVANCE

Independent suture augmentation of a quadrupled SemiT graft improves ACLR construct biomechanics. Outcomes were improved with augmentation using 2.0-mm tape suture compared to 1.3-mm tape suture.

A prospective randomized controlled study of hamstring and bone-free quadriceps tendons autografts in arthroscopic ACL reconstruction

INTRODUCTION

Anterior cruciate ligament (ACL) reconstruction is one of the most common surgical procedures worldwide. However, the ideal graft source is still debatable. This study compared hamstring (HT) and bone-free quadriceps (QT) tendon autografts in terms of muscle strength and patient-reported outcomes.

METHODS

Between June 2018 and December 2019, 46 patients were enrolled in the study and randomly assigned to one of two groups for the ACL reconstruction surgery-the HT autograft group or the QT autograft group. An experienced examiner performed preoperative and postoperative examinations. The HUMAC NORM isokinetic machine (Computer Sports Medicine International-CSMI, 2004) was used to assess flexor and extensor thigh muscle strength. Both groups received the same surgical technique and fixation method. All patients were examined after three, six, nine, and 12 months. The final evaluations were performed at the 24-month follow-up. Patients' scores on the International Knee Documentation Committee (IKDC) evaluation form and the Lysholm Knee Scoring Scale were used to evaluate patient-reported outcomes. The two groups were also compared in terms of postoperative complications and activity levels.

RESULTS

The difference between preoperative and postoperative knee flexor peak torques (FPT) was lower in the QT group than in the HT group. The average difference between preoperative and postoperative knee extensor peak torque (EPT) was higher in the QT group than in the HT group. As a result, the HT group had a lower postoperative H/Q ratio (flexor strength normalized to body mass divided by extensor strength normalized to body mass) than the QT group (p < 0.001). The mean IKDC scores for the HT and QT groups were 90.13 ± 6.99 and 87.12 ± 6.61, respectively. The scores of the two groups postoperatively were close, and both groups showed significant improvement. The average graft size in the QT group was significantly greater than that in the HT group. Saphenous nerve palsy was the most common complication in the HT group (22%). Thigh hematomas were observed in two patients in the QT group and required urgent intervention (12%).

CONCLUSION

After ACL reconstruction, we found a significant decrease in strength at the donor sites in both techniques, with similar patient-reported measures and stability outcomes. The H/Q strength ratio was higher in the QT group postoperatively, which may have a protective effect on the reconstructed ligament. Level of Evidence I It is a randomized controlled trial.

Approximately half of pediatric or adolescent patients undergoing revision anterior cruciate ligament reconstruction return to the same level of sport or higher: A systematic review

PURPOSE

To summarise the surgical techniques and clinical outcomes in paediatric and adolescent patients undergoing revision anterior cruciate ligament reconstruction (r-ACLR).

METHODS

Three databases (MEDLINE, PubMed and EMBASE) were searched from inception to 29 July 2023. The authors adhered to the PRISMA and R-AMSTAR guidelines as well as the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, surgical details, patient-reported outcome measures (PROMs), rates of instability, rupture and return to sport (RTS) were extracted.

RESULTS

Eight studies comprising 706 (711 knees) patients were included (48.7% female). The mean age at r-ACLR was 17.1 years (range: 16.5-18.0). Autografts (67.5%) were more common than allografts (32.2%) in revision, with bone-patellar tendon-bone (BPTB) being the most prevalent autograft source (59.6%). Bone grafts were used in seven patients (4.8% of 146 patients). The most common femoral and tibial fixation techniques were interference screws (37.6% and 38.1%, of 244 patients, respectively). The most common tunnelling strategy was anatomic (69.1% of 236 patients), and meniscus repairs were performed in 39.7% of 256 patients. The re-rupture rate was 13.0% in 293 patients. RTS at the same level or higher was 51.6% in 219 patients. The mean (SD) Lysholm score was 88.1 (12.9) in 78 patients, the mean (SD) Tegner score was 6.0 (1.6) in 78 patients, and the mean (SD) IKDC score was 82.6 (16.0) in 126 patients.

CONCLUSION

R-ACLR in paediatric and adolescent patients predominantly uses BPTB autografts and interference screw femoral and tibial fixation with concomitant meniscal procedures. Rates of re-rupture and RTS at the same level or higher were 13.0% and 51.6%, respectively. Information from this review can provide orthopaedic surgeons with a comprehensive understanding of the most commonly used operative techniques and their outcomes for revision ACLR in this population.

LEVEL OF EVIDENCE

Level IV.

Near complete quadriceps tendon healing 2 years following harvest in anterior cruciate ligament reconstruction

PURPOSE

Despite the recent increase in the use of quadriceps tendon (QT) autograft in anterior cruciate ligament reconstruction (ACLR); however, there remains a paucity of literature evaluating the postoperative morphology of the QT. The present study aimed to determine the postoperative morphologic change of the QT at a minimum of 2 years following harvesting during ACLR.

METHODS

Patients who underwent ACLR with QT autograft and underwent magnetic resonance imaging (MRI) at a minimum of 2 years following harvesting were retrospectively included in the study. The anterior-to-posterior (A-P) thickness, medial-to-lateral (M-L) width, cross-sectional area (CSA), and signal/noise quotient (SNQ) of the QT were assessed at 5 mm, 15 mm, and 30 mm proximal to the superior pole of the patella on MRI. The CSA was adjusted by the angle between the QT and the plane of the axial cut based on a cosine function (adjusted CSA). The A-P thickness, M-L width, adjusted CSA, and SNQ were compared pre- and postoperatively. In addition, defects or scar tissue formation in the harvest site were investigated on postoperative MRI.

RESULTS

Thirty patients were recruited for the study. The mean duration between postoperative MRI and surgery was 2.8 ± 1.1 years. The mean A-P thickness was 10.3% and 11.9% larger postoperatively at 5 mm and 15 mm, respectively. The mean M-L width was 7.3% and 6.5% smaller postoperatively at 5 mm and 15 mm, respectively. There were no significant differences in the adjusted CSA between pre- and post-operative states (275.7 ± 71.6 mm2 vs. 286.7 ± 91.8 mm2, n.s.). There was no significant difference in the postoperative change in the SNQ of the QT at all assessment locations. Defect or scar tissue formation at the harvest site was observed in 4 cases (13.3%), and 5 cases (16.6%), respectively.

CONCLUSION

At a minimum of 2 years following QT harvest during ACLR, the QT became slightly thicker and narrower (approximately 11% and 7%, respectively). While the current study demonstrates that QT re-harvesting can be considered due to nearly normalized tendon morphology, future histological and biomechanical studies are required to determine the re-harvesting potential of the QT.

LEVEL OF EVIDENCE

IV.

Assessment of Return to Sport After ACL Reconstruction With Soft Tissue Autograft in Adolescent Athletes: Quadriceps Versus Hamstring Tendon

Background

Quadriceps tendon soft tissue autograft represents an increasingly popular graft option for anterior cruciate ligament reconstruction (ACLR), particularly for adolescents, some of whom have an open physis, precluding use of graft options with bone plugs.

Purpose/Hypothesis

The purpose of this study was to quantify return-to-sport performance assessments in adolescents at 6 months after ACLR with all-soft tissue quadriceps tendon autograft (ACLR-Q) versus hamstring tendon autograft (ACLR-HS). It was hypothesized that ACLR-Q would be associated with improved hamstring strength and hamstring-to-quadriceps (HS:Q) ratios compared with ACLR-HS, albeit with decreased quadriceps strength.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were patients aged 12 to 19 years who underwent primary ACLR by a single surgeon and who completed a return-to-sport performance assessment between 5 and 9 months postoperatively. The performance assessment included manual muscle strength tests (hamstring, quadriceps, hip abductor and adductor), dynamic balance test (Y-balance), and functional hop tests (single hop, triple hop, crossover hop, 6-m timed hop). Data were converted to limb symmetry indices, and limb symmetry index deficits were compared between the ACLR-Q and ACLR-HS cohorts using the Student t test or Wilcoxon-Mann-Whitney test.

Results

An initial cohort of 90 ACLR-Q patients was compared with 54 ACLR-HS patients, with no significant differences in patient characteristics. Differences in meniscal repair rates, however, prompted use of propensity score matching on age, sex, body mass index, meniscectomy, and meniscal repair to produce comparable subcohorts. The matching resulted in 67 ACLR-Q and 52 ACLR-HS patients. Hamstring strength deficits were significantly greater in ACLR-HS versus ACLR-Q patients (-40.5% vs -5.7%; P < .001). Quadriceps strength deficits were significantly greater in ACLR-Q versus ACLR-HS patients (-12.8% vs -0.4%; P < .001). ACLR-Q patients had a significantly greater HS:Q ratio on the operative knee (P < .001) and significantly higher Y-balance composite score deficits (-2.9% vs -0.4%; P = .01) than ACLR-HS patients. There were no significant differences in hop test performance between groups.

Conclusion

Adolescent athletes who underwent ACLR-Q showed significantly greater quadriceps strength deficits but significantly smaller hamstring strength deficits than those who underwent ACLR-HS, leading to more favorable HS:Q ratios in ACLR-Q patients at 6 months postoperatively.

Comparison of Knee Pain and Difficulty With Kneeling Between Patellar Tendon and Hamstring Tendon Autografts After Anterior Cruciate Ligament Reconstruction: A Study From the New Zealand ACL Registry

BACKGROUND

The bone-patellar tendon-bone (BTB) autograft is associated with difficulty with kneeling after anterior cruciate ligament (ACL) reconstruction; however, it is unclear whether it results in a more painful or symptomatic knee compared with the hamstring tendon autograft.

PURPOSE

To identify the rate and risk factors for knee pain and difficulty with kneeling after ACL reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Primary ACL reconstruction procedures prospectively recorded in the New Zealand ACL Registry from April 2014 to May 2021 were analyzed. The Knee injury and Osteoarthritis Outcome Score (KOOS) was used to identify patients reporting consequential knee pain (CKP), defined as a KOOS Pain subscore of ≤72 points, and severe kneeling difficulty (SKD), defined as a self-report of "severe" or "extreme" difficulty with kneeling. Absolute values of the KOOS Pain and Symptoms subscales were also compared.

RESULTS

A total of 10,999 patients were analyzed. At 2-year follow-up, 9.3% (420/4492) reported CKP, and 12.0% (537/4471) reported SKD. The most important predictor of CKP at 2-year follow-up was having significant pain before surgery (adjusted odds ratio, 4.10; P < .001). The most important predictor of SKD at 2-year follow-up was the use of a BTB autograft rather than a hamstring tendon autograft (21.3% vs 9.4%, respectively; adjusted odds ratio, 3.12; P < .001). There was no difference between the BTB and hamstring tendon grafts in terms of CKP (9.9% vs 9.2%, respectively; P = .494) or in absolute values of the KOOS Pain (mean, 88.7 vs 89.0, respectively; P = .37) and KOOS Symptoms (mean, 82.5 vs 82.1, respectively; P = .49) subscales.

CONCLUSION

At 2-year follow-up after primary ACL reconstruction, 9.3% of patients reported CKP, and 12.0% reported SKD. The BTB autograft was associated with difficulty with kneeling, but it did not result in a more painful or symptomatic knee compared with the hamstring tendon autograft.

Contribution of the Medial Hamstrings to Valgus Stability of the Knee

Background

Multiligament knee injuries involving the medial side are common. When performing surgical reconstruction, use of the medial hamstrings (HS) as grafts remains controversial in this setting.

Purpose

To determine the role of the medial HS in stabilizing the valgus knee for different types of medial-sided knee injury.

Study Design

Controlled laboratory study.

Methods

A biomechanical study on 10 cadaveric knees was performed. Valgus load (force moment of 10 N/m) was applied at 0°, 30°, and 60° of flexion, and the resultant rotation was recorded using an optoelectronic motion analysis system. Measurements were repeated for 4 different knee states: intact knee, superficial medial collateral ligament (sMCL) injury, deep medial collateral ligament (dMCL) injury, and posterior oblique ligament (POL) injury. For each state, 4 loading conditions (+ loaded; - unloaded) of the semitendinosus (ST) and gracilis (GRA) tendons were tested: ST+/GRA+, ST+/GRA-, ST-/GRA+, and ST-/GRA-.

Results

At 0° of flexion, combined unloading of the ST and GRA (ST-/GRA-) increased valgus laxity on the intact knee compared with the ST+/GRA+ condition (P < .05). For all medial-sided injury states (isolated sMCL; combined sMCL and dMCL; and combined sMCL, dMCL, and POL damage), ST-/GRA- increased valgus laxity at 0° and 30° of flexion versus ST+/GRA+ (P < .05 for all). The absolute value of valgus laxity increased with the severity of medial-sided ligament injury. Isolated ST unloading increased valgus laxity for the intact knee and the MCL-injured knee (combined sMCL and dMCL) at 0° of flexion (P < .05 vs ST+/GRA+). Isolated unloading of the GRA had no effect on valgus knee stability.

Conclusion

The medial HS tendons contributed to the stabilization of the knee in valgus, and this was even more important when the medial side was severely affected (POL damage). This stabilizing effect was greater between 0° and 30°, in which the POL is the main valgus stabilizer.

Clinical Relevance

When deciding on graft selection for multiligament knee injury reconstruction, the surgeon should be aware of the effect of harvesting the medial HS tendon on valgus laxity.

Preserving the hamstring tendon insertion during ACL reconstruction with an autograft: Systematic literature review

INTRODUCTION

The hamstring tendons (gracilis and semitendinosus) are often used as an autograft for anterior cruciate ligament (ACL) reconstruction. Healing of this graft involves a slow biological process called ligamentization. To encourage this process, some authors have proposed preserving the insertion of the hamstring tendons.

HYPOTHESIS

Leaving the tibial insertion of the hamstring tendons intact will provide better early biological incorporation and superior tibial mechanical fixation resulting in various clinical advantages.

MATERIALS AND METHODS

In January 2022, a systematic literature review was carried out independently by two authors of the Medline, PubMed and Embase databases. The keywords used were "pedicular" or "pedicled" or "preservation of tibial attachment" or "hamstring tibial insertion" AND "ACL reconstruction". Each author's data was analyzed separately.

RESULTS

Sixteen articles were analyzed. Preserving the hamstring tibial insertion during ACL reconstruction improves the graft's biological incorporation during the initial postoperative phase according to clinical studies with MRI analysis and provides a mechanical advantage at the graft's tibial attachment according to biomechanical studies (construct up to 65% stiffer). There was no difference in the clinical and functional scores when compared to the conventional technique in which the hamstring tendons are detached from their tibial insertion.

DISCUSSION

The main conclusion of this systematic literature review was that preserving the hamstring tibial insertion during ACL reconstruction appears to improve the graft's ligamentization with biological and mechanical advantages relative to detaching the hamstring tendons. The clinical and functional results were comparable to other techniques. Prospective studies with large cohorts are still needed to confirm these findings.

LEVEL OF EVIDENCE

IV; Systematic review of literature.

Revision Rates After Primary Allograft ACL Reconstruction by Allograft Tissue Type in Older Patients

Background

While there is extensive literature on the use of allograft versus autograft in anterior cruciate ligament (ACL) reconstruction, there is limited clinical evidence to guide the surgeon in choice of allograft tissue type.

Purpose

To assess the revision rate after primary ACL reconstruction with allograft and to compare revision rates based on allograft tissue type and characteristics.

Study Design

Cohort study; Level of evidence, 3.

Methods

Patients who underwent primary allograft ACL reconstructions at a single academic institution between 2015 and 2019 and who had minimum 2-year follow-up were included. Exclusion criteria were missing surgical or allograft tissue type data. Demographics, operative details, and subsequent surgical procedures were collected. Allograft details included graft tissue type (Achilles, bone-patellar tendon-bone [BTB], tibialis anterior or posterior, semitendinosus, unspecified soft tissue), allograft category (all-soft tissue vs bone block), donor age, irradiation duration and intensity, and chemical cleansing process. Revision rates were calculated and compared by allograft characteristics.

Results

Included were 418 patients (age, 39 ± 12 years; body mass index, 30 ± 9 kg/m2). The revision rate was 3% (11/418) at a mean follow-up of 4.9 ± 1.4 years. There were no differences in revision rate according to allograft tissue type across Achilles tendon (3%; 3/95), BTB (5%; 3/58), tibialis anterior or posterior (3%; 5/162), semitendinosus (0%; 0/46), or unspecified soft tissue (0%; 0/57) (P = .35). There was no difference in revision rate between all-soft tissue versus bone block allograft (6/283 [2%] vs 5/135 [4%], respectively; P = .34). Of the 51% of grafts with irradiation data, all grafts were irradiated, with levels varying from 1.5 to 2.7 Mrad and 82% of grafts having levels of <2.0 Mrad. There was no difference in revision rate between the low-dose and medium-to high-dose irradiation cohorts (4% vs 6%, respectively; P = .64).

Conclusion

Similarly low (0%-6%) revision rates after primary ACL reconstruction were seen regardless of allograft tissue type, bone block versus all-soft tissue allograft, and sterilization technique in 418 patients with mean age of 39 years. Surgeons may consider appropriately processed allograft tissue with or without bone block when indicating ACL reconstruction in older patients.

Return to Sports After ACL Augmentation With Anterolateral Reconstruction (ALR) Harvesting Gracilis Only Compared With ACL Reconstruction With ALR Harvesting Both Hamstring Tendons

BACKGROUND

Anterior cruciate ligament (ACL) repair (ACL-Rp) is known to be a valuable alternative to ACL reconstruction (ACL-Rc) in selected indications. The majority of the ACL-Rp techniques recommend the use of a synthetic brace. The use of the gracilis allows both a biological internal brace and anterolateral ligament reconstruction (ALR).

PURPOSE

The primary objective was to compare the early ability to return to sports between patients who underwent ACL-Rp using a gracilis autograft as an internal brace augmentation with ALR and patients who underwent the conventional ACL-Rc with ALR technique sacrificing both the gracilis and the semitendinosus. The secondary objective was to compare the failure rate, clinical scores, and return to sports at a minimum follow-up of 2 years.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective analysis was undertaken. A total of 49 patients who underwent ACL-Rp with ALR between December 2018 and May 2019 were propensity matched at a 1:1 ratio to those who underwent ACL-Rc with ALR during the same period. The decision to perform ACL-Rp with ALR was based on preoperative selection and intraoperative arthroscopic findings: proximal avulsion tear, partial ACL tear, low- to midlevel sports participation, and good tissue quality. The ability to return to sports was assessed using isokinetic tests and the Knee Santy Athletic Return to Sport test functional test at 6 months postoperatively. At the final follow-up, knee laxity parameters, return to sports, and clinical outcome (Lysholm score, Tegner Activity Scale score, International Knee Documentation Committee score, Knee injury and Osteoarthritis Outcome Score, and Anterior Cruciate Ligament-Return to Sport after Injury score) were recorded.

RESULTS

The ACL-Rp group had significantly less hamstring strength deficit when compared with their counterparts who underwent ACL-Rc (0.2% vs 10.2% in concentric, P < .001; 2.5% vs 14% in eccentric, P < .001). The mean Knee Santy Athletic Return to Sport test score was significantly higher in the ACL-Rc group (69.7% ± 16.6% [range, 19%-100%] vs 61% ± 16.8% [range, 19%-100%]; P = .001). In the ACL-Rp group, 61% (30/49) of the patients were authorized to return to pivot sports versus 41% (20/49) in the ACL-Rc group (P = .04). At a mean final follow-up of 31.4 ± 3.5 months, no significant differences were demonstrated between groups with respect to clinical scores and knee laxity parameters. There was a trend for a higher failure rate in the ACL-Rp group without any significance (ACL-Rp: 6.1% [3/49] vs ACL-Rc: 0%; P = .08).

CONCLUSION

At 6 months after operation, harvesting only the gracilis with this ACL-Rp and augmentation with ALR technique was linked to a better early ability to return to sports compared with the ACL-Rc with ALR technique harvesting both the gracilis and semitendinosus. This technique had a limited effect on early flexion strength and provided a satisfactory rerupture rate.

Low-Volume Surgeons Use Allograft in Younger Patients and Show Greater Rates of Revision Following Primary Allograft Anterior Cruciate Ligament Reconstruction Compared With High-Volume Surgeons

Purpose

To determine whether surgeon volume affects revision rate following primary anterior cruciate ligament reconstruction (ACLR) with allograft and to determine whether surgeon volume impacts allograft tissue type used.

Methods

All patients aged 14 years or older who underwent primary allograft ACLR at a large hospital system between January 2015 to December 2019 with minimum 2-year follow-up were included. Patients with double-bundle ACLR, multiligament reconstruction, and absent allograft type data were excluded. Surgeon volume was categorized as 35 or more ACLR/year for high-volume surgeons and less than 35 ACLR/year for low-volume surgeons. Revision was defined as subsequent ipsilateral ACLR. Patient characteristics, operative details, allograft type, and revision ACLR rates were retrospectively collected. Revision rate and allograft type were analyzed based on surgeon volume.

Results

A total of 457 primary allograft ACLR cases (mean age: 38.8 ± 12.3 years) were included. Low-volume surgeons experienced greater revision rates (10% vs 5%, P = .04) and used allograft in a younger population (37.6 vs 40.0 years old, P = .03) than high-volume surgeons. Subgroup analysis of the total cohort identified a significantly increased failure rate in patients <25 years old compared with ≥25 years old (30% vs 4%, P < .001). Allograft type selection varied significantly between surgeon volume groups, with low-volume surgeons using more bone-patellar tendon-bone (P < .001) and less semitendinosus allograft (P = .01) than high-volume surgeons. No differences in revision rate were observed based on allograft type (P = .71).

Conclusions

There was a greater revision rate following primary allograft ACLR among low-volume surgeons compared with high-volume surgeons. Low-volume surgeons also used allograft in a younger population than did high-volume surgeons.

Level of Evidence

Level III, retrospective comparative prognostic trial.

Combined press-fit and extracortical fixation in patellar tendon anterior cruciate ligament reconstruction results in reliable graft fixation and early bone block incorporation

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction with bone-patellar-tendon-bone (BPTB) autograft has the potential biological advantage of direct bone-to-bone healing over soft tissue grafts. The primary aim of this study was to investigate possible graft slippage and therefore fixation strength in a modified BPTB autograft technique with suspensory fixation on both sides for primary ACL reconstruction until bony integration takes place.

METHODS

Twenty-one patients undergoing primary ACL reconstruction with a modified BPTB autograft (bone-on-bone (BOB) technique) between August 2017 and August 2019 were included in this prospective study. A computed tomography (CT) scan of the affected knee was performed directly postoperatively, as well as 3 months postoperatively. Examiner-blinded parameters for graft slippage, early tunnel widening, bony incorporation, as well as remodeling of the autologous refilled patellar harvest site were investigated.

RESULTS

A series of 21 patients treated with a BPTB autograft with this technique underwent two CT investigations. Comparison of CT scans showed no bone block displacement and therefore no graft slippage in the patient cohort. Only one patient showed signs of early tunnel enlargement. Radiological bone block incorporation took place showing bony bridging of the graft to the tunnel wall in 90% of all patients. Furthermore, 90% showed less than 1 mm bone resorption of the refilled harvest site at the patella.

CONCLUSIONS

Our findings suggest graft fixation stability and reliability of anatomic BPTB ACL reconstruction with a combined press-fit and suspensory fixation technique by absence of graft slippage within the first 3 months postoperatively.

Excellent short-term results of dome-shaped high tibial osteotomy combined with all-inside anterior cruciate ligament reconstruction

PURPOSE

This study aimed to evaluate short-term outcomes at least 2 years after dome-shaped high tibial osteotomy (HTO) combined with all-inside anterior cruciate ligament reconstruction (ACL) in patients with persistent ACL insufficiency accompanied by pain due to varus deformity.

METHODS

The study enrolled 19 knees of 18 patients. The mean age was 58.4 ± 13.4 years and the mean postoperative follow-up period was 31.4 ± 6.6 months (24-49 months). JOA(Japanese Orthopaedic Association)-OA(osteoarthritis) score, Lysholm score, radiographic outcomes such as femoro-tibia angle (FTA) in a standing position, side-to-side difference in KT-1000 measurements were evaluated at pre op. and post operative final follow up. And arthroscopic evaluation was evaluated at the time of the HTO plate-removal procedure.

RESULTS

Before surgery, the mean JOA-OA score was 65.0 ± 13.5, the mean Lysholm score was 47.2 ± 16.2, the mean femoro-tibia angle (FTA) in a standing position was 183.8 ± 3.4° (range;180-190°), and the mean side-to-side difference in KT-1000 measurements was 4.1 ± 1.3 mm. After surgery, the mean JOA-OA score, Lysholm score, and side-to-side difference in KT-1000 measurements improved to 93.1 ± 6.0 (P < 0.00001), 94.2 ± 5.9 (P < 0.00001), and -0.2 ± 0.8 mm (P < 0.00001), respectively. The mean FTA decreased to 168.0 ± 3.3 (P < 0.00001), and the mean posterior tibial slope angle decreased to 5.0 ± 3.6° from 6.9 ± 2.6° preoperatively (P = 0.024). Arthroscopic evaluation during the HTO plate-removal procedure of 17 knees were performed at a mean of 16 months after the surgery. The reconstructed ACL graft in 13 knees were successful, a cyclops lesion in one knee, and looseness of the graft in three knees.

CONCLUSIONS

Dome-shaped HTO allows for a relatively high degree of varus correction and decreases the steep posterior tibial slope that causes excessive load on the ACL. Therefore, its use in combination with ACL reconstruction seems to be effective.

Long-term results after anterior cruciate ligament reconstruction using patellar tendon versus hamstring tendon autograft with a minimum follow-up of 10 years-a systematic review

INTRODUCTION

A lot of research addresses superiority of the two commonly used autografts bone-patellar tendon-bone (BPTB) and hamstring tendon for anterior cruciate ligament (ACL) reconstruction, without getting to consensus. While there are numerous studies and reviews on short- to mid-term follow-up, not much literature is available on long-term follow-up. As patients suffering ACL injuries are often of young age and high athletic activity, it is crucial to have the best evidence possible for graft choice to minimize consequences, like osteoarthritis later on.

MATERIALS AND METHODS

A search of the online databases, PubMed and Embase, was carried out last on 31st March 2022 for studies comparing BPTB and hamstring tendon (HT) autografts for ACL reconstruction in human patients with a minimum follow-up of 10 years. The methodological quality of each study has been evaluated using the modified Coleman Methodology Score. Results on the three variables patient-oriented outcomes, clinical testing and measurements and radiographic outcomes were gathered and are presented in this review.

RESULTS

Of 1299 records found, nine studies with a total of 1833 patients were identified and included in this systematic review. The methodological quality of the studies ranged from a Coleman Score of 63-88. Many studies reported no or only few statistically significant differences. Significant results in favour of BPTB were found for activity levels and for instrumented laxity testing with the KT-1000 arthrometer. Better outcomes for HT were found in IKDC-SKF, the KOOS, donor site morbidity, pivot shift test, radiographic osteoarthritis (IKDC C or D) and contralateral ACL rupture. No studies presented significant differences in terms of Lysholm Score or Tegner Activity Score, Lachman test, single-legged hop test, deficits in range of motion, osteoarthritis using the Kellgren and Lawrence classification or graft rupture.

CONCLUSION

We cannot recommend one graft to be superior, since both grafts show disadvantages in the long-term follow-up. Considering the limitation of our systematic review of no quantitative analysis, we cannot draw further conclusions from the many insignificant results presented by individual studies.

LEVEL OF EVIDENCE

IV.

Knee Extensor Mechanism Complications After Autograft Harvest in ACL Reconstruction: A Systematic Review and Meta-analysis

Background

Existing systematic reviews have sought to characterize the relative donor-site morbidity of bone-patellar tendon-bone (BTB) and quadriceps tendon (QT) grafts after anterior cruciate ligament reconstruction (ACLR). However, no studies have reported the pooled proportions of patellar fractures and donor tendon ruptures across the body of literature.

Purpose

To estimate the proportion of patellar fractures, patellar tendon ruptures, and QT ruptures associated with BTB or QT autograft harvest during ACLR using published data.

Study Design

Systematic review; Level of evidence, 4.

Methods

A meta-analysis was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using 3 online databases (PubMed, Scopus, and Web of Science). A total of 800 manuscripts were included in the initial research of peer-reviewed articles in English that reported extensor mechanism complications associated with graft harvest in patients after ACLR. Pooled proportions of patellar fractures, patellar tendon ruptures, and QT ruptures were calculated for each graft type (BTB, QT) using a random-effects model for meta-analysis.

Results

A total of 28 studies were analyzed. The pooled proportion of patellar fractures was 0.57% (95% CI, 0.34%-0.91%) for the BTB harvest and 2.03% (95% CI, 0.78%-3.89%) for the QT harvest. The proportion of patellar tendon ruptures was 0.22% (95% CI, 0.14%-0.33%) after the BTB harvest, and the proportion of QT ruptures was 0.52% (95% CI, 0.06%-1.91%) after the QT harvest. The majority of included studies (16/28 [57.1%]) had an evidence level of 4.

Conclusion

Based on the current literature, the proportion of extensor mechanism complications after ACLR using either a BTB or a QT autograft is low, indicating that the extensor mechanism harvest remains a safe option. A higher proportion of patellar fractures was noted for QT grafts and a higher proportion of donor tendon ruptures was noted for QT grafts compared with BTB grafts.