Allograft tendons are a safe and effective option for revision ACL reconstruction: a clinical review

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.

Revision Anterior Cruciate Ligament Reconstruction and Associated Procedures

Failure of anterior cruciate ligament reconstruction (ACLR) is a common yet devastating complication due to inferior clinical outcomes associated with revision ACLR. Identifying the cause and associated risk factors for failure is the most important consideration during preoperative planning. Special attention to tunnel quality, concomitant injuries, and modifiable risk factors will help determine the optimal approach and staging for revision ACLR. Additional procedures including lateral extra-articular tenodesis and osteotomy may be considered for at-risk populations. The purpose of this review is to explore causes of ACLR failure, clinical indications and appropriate patient evaluation, and technical considerations when performing revision ACLR.

Allografts use in orthopedic surgery: trend change over the past 11 years from a regional tissue bank

Allografts are the second most transplanted tissue in medicine after blood and are now increasingly used for both primary and revision surgery. Allografts have the advantages of lower donor site morbidity, availability of multiple grafts, and shorter operative time. The Banks represents the bridge between Donor and Recipient and guarantees the quality and safety of the distributed allografts Given the increasing interest in these tissues, a retrospective analysis of data collected from the Regional Musculoskeletal Tissue Bank registry over an 11-year period (2009-2019) was conducted. The statistical analyses used were the Shapiro-Wilk normality test and a Poisson regression model. From January 2009 to December 2019, a total of 14,199 musculoskeletal tissues stored in the Regional Musculoskeletal Tissue Bank were provided for surgical allograft procedures. In 2009, the number of allografts performed was 925; this figure has steadily increased to 1599 in 2019. Epiphyses were taken as the reference tissue with an almost constant trend over the period, while a significant increase was denoted for extensor mechanism allograft, ligaments, tendons and long bone corticals (p < 0.001), processed bone tissues had no change in trend (p = 0.841). There was also a gradual decrease in the rate of microbiological positivity, as determined by bacteriological and serological tests performed on the collected tissues. This phenomenon is due to improved sampling techniques and the training of a dedicated team. Thus, we have seen how the use of allografts in orthopedic surgery has increased over the past 11 years, uniformly in terms of tissue type, except for the noticeable increase in ligamentous tissue.

Peroneus longus tendon autograft versus allograft in revision ACLR: A retrospective comparison

PURPOSE

The use of peroneus longus tendon (PLT) autografts in primary anterior cruciate ligament reconstruction (ACLR) has increased recently, but there is a lack of research on its use in revision ACLR. This study aimed to compare the clinical outcomes and complications between revision ACLR using allografts and PLT autografts.

MATERIALS AND METHODS

Fifty-nine patients who underwent arthroscopic revision of ACLR with complete clinical follow-ups between 2012 and 2021 were retrospectively reviewed. Allograft was used in 44 of these patients, and PLT autograft was used in 15 of them. Lysholm knee score, Tegner activity score, Lachman, and anterior drawer tests were performed after a mean follow-up of 60months (range: 19-116). The American Orthopaedic Foot and Ankle Society (AOFAS) scale was used to evaluate the donor ankle functions. Clinical outcomes and complications were compared between groups.

RESULTS

Both groups showed significantly improved functional outcomes compared to their preoperative assessments. However, both groups had similar clinical results at the final follow-up, including Lysholm knee score, Tegner activity scale, knee range of motion, return to sports, time to return to daily activities, and rate of re-rupture. No major complications were seen in any of the patients. The AOFAS score was 99.13±2.64 in the PLT autograft group without loss of ankle muscle strength, deformity, instability, and permanent iatrogenic neurovascular injuries. The cumulative cost of the allograft group was significantly higher than the PLT autograft group.

CONCLUSIONS

The PLT autograft might be an alternative autograft option to allografts due to similar clinical outcomes, low donor site morbidity, and reduced cost in ACLR revisions, especially if the primary ACLR was performed using grafts harvested around the knee.

LEVEL OF EVIDENCE

III; retrospective comparative study.

A Comparative Analysis of Quadriceps Tendon, Patellar Tendon Bone Allograft, and Cadaver Graft in Anterior Cruciate Ligament (ACL) Repair and Reconstructive Surgery

Anterior cruciate ligament (ACL) injuries are a common occurrence among athletes and active individuals, often necessitating surgical intervention for optimal recovery. The choice of graft material for ACL reconstruction remains a topic of debate, with various options available, including quadriceps tendon (QT), patellar tendon bone allograft (PTBA), and cadaver graft (CG). This paper aims to provide an extensive review and comparison of the efficacy, outcomes, and complications associated with these graft types based on recent research. A systematic literature search following PRISMA guidelines was conducted to identify relevant studies published in the past six years. The findings suggest that while each graft type has its advantages and limitations, there is no definitive superior choice. Factors such as patient age, activity level, comorbidities, and surgeon preference should be considered when selecting the most appropriate graft for ACL repair surgery. QT grafts are associated with lower donor-site morbidity compared to patellar tendon grafts. However, QT grafts may have a higher risk of graft rupture and decreased knee flexion strength. PTBA grafts, compared to QT grafts, have a higher risk of donor-site morbidity but a lower risk of graft rupture and improved knee stability. CG grafts have lower donor-site morbidity compared to PTBA grafts but may have a higher risk of graft rupture and decreased knee flexion strength compared to PTBA grafts. In conclusion, the choice of graft material for ACL reconstruction is a complex decision that requires careful consideration of various factors, including patient age, activity level, comorbidities, and surgeon preference. While each graft type has its advantages and limitations, there is no definitive superior choice. Therefore, it is essential to carefully weigh the risks and benefits of each graft type to ensure optimal outcomes for patients undergoing ACL repair surgery.

The Influence of Tibial Tubercle-Sparing Slope-Reducing Osteotomy on Patellar Height in Patients Undergoing Revision ACL Reconstruction

BACKGROUND

A posterior tibial slope (PTS) >12° is an independent risk factor for anterior cruciate ligament (ACL) graft rupture, and a high tibial osteotomy (HTO) for slope correction can help avoid it. Management of patellar height is of major concern when performing HTO.

PURPOSE

To evaluate the effect of tibial tubercle-sparing anterior closing-wedge osteotomy on patellar height in revision ACL reconstruction (ACLR).

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients who underwent arthroscopic revision ACLR combined with retro-tibial tubercle anterior closing-wedge HTO (ACW-HTO) between January 1, 2016, and March 31, 2021, were assessed for eligibility. Patellar height was measured on full weightbearing lateral radiographs according to the Insall-Salvati index (ISI) and Caton-Deschamps index (CDI) or frontal radiographs using the femoral patellar height index. The PTS was evaluated using the proximal anatomic axis of the tibia on standard short lateral radiographs. The delta (postoperative - preoperative) and the ratio (preoperative/postoperative) of the 3 patellar height indices and PTS were calculated. Preoperative and postoperative patellar heights were compared using independent t tests for each index. Also investigated was whether patients changed patellar height category (baja, normal, or alta) after slope osteotomy.

RESULTS

Among 475 revision ACLRs, 47 tibial tubercle-sparing ACW-HTOs were retained for analysis. No significant difference in patellar height was found between pre- and postoperative radiographs regardless of the index (preoperative - postoperative) (ISI: 1.0 ± 0.2 - 0.9 ± 0.2, P = .1729; CDI: 1.0 ± 0.2 - 1.0 ± 0.2, P = .4034; femoral patellar height index: 1.5 ± 0.2 - 1.5 ± 0.2; P = .5130). Fifteen patients (31.9%) exhibited a postoperative change in their patellar height category when measured by the ISI (6 moved up a category, 9 moved down one), and 18 patients (38.3%) changed category according to the CDI (10 moved up a category, 8 moved down one). No significant difference was found between pre- and postoperative patellar height among these patients (ISI: P = .2418; CDI: P = .3005).

CONCLUSION

Changes in patellar height ratio are common after tibial tubercle-sparing ACW-HTO in patients undergoing revision ACLR. The clinical effect of these changes is unknown, and further study is needed to investigate whether they may result in patellofemoral symptoms.

Revision anterior cruciate ligament reconstruction using the ipsilateral Quadriceps tendon autograft: a modular reconstructive option

PURPOSE

Failed ACL reconstruction is a common occurrence nowadays due to the increased incidence of ACL surgeries and return to full activities following the surgery. Several challenges might stand in the face of this revision surgery particularly the graft harvest and its suitability to the situation with possible widening of the tunnel and the avoidance of additional morbidity at the contralateral side or anterior knee pain as in patellar tendon harvest. The aim of this study is to evaluate the ipsilateral quadriceps tendon as a source of autograft in revision ACL surgery which constitutes a viable option that can potentially decrease the morbidity of the procedure, and meanwhile provide a graft substitute that can be tailored to suit the dilated tunnels commonly encountered in revision surgery, thus giving the patients a good potential for better functional outcome.

METHODS

Revision anterior cruciate ligament reconstruction was done in 30 patients using the ipsilateral quad tendon as a pure soft tissue or with a bony fragment.

RESULTS

The mean subjective international Knee Documentation Committee score (IKDC score) at two years follow-up was 65.83 ± 7.20. There is statistically significant improvement of the objective as well as the subjective IKDC scores at the end of follow-up when compared to the preoperative as well as the 6-month evaluation figures. The KT1000 arthrometer recorded a mean of 4.50 ± 1.07. Significant improvement of the limb symmetry index was at two years duration.

CONCLUSIONS

The quadriceps tendon can be a solution for several challenges that might appear during the revision ACL surgery with comparable results to other tendons and with minimal morbidity on the function of the harvested muscle tendon.

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.

Influence of Staphylococcus epidermidis biofilm on the mechanical strength of soft tissue allograft

We sought to determine the impact of bacterial inoculation and length of exposure on the mechanical integrity of soft tissue tendon grafts. Cultures of Staphylococcus epidermidis were inoculated on human tibialis posterior cadaveric tendon to grow biofilms. A low inoculum in 10% growth medium was incubated for 30 min to replicate conditions of clinical infection. Growth conditions assessed included inoculum concentrations of 100, 1000, 10,000 colony-forming units (CFUs). Tests using the MTS Bionix system were performed to assess the influence of bacterial biofilms on tendon strength. Load-to-failure testing was performed on the tendons, and the ultimate tensile strength was obtained from the maximal force and the cross-sectional area. Displacements of tendon origin to maximal displacement were normalized to tendon length to obtain strain values. Tendon force-displacement and stress-strain relationships were calculated, and Young's modulus was determined. Elastic modulus and ultimate tensile strength decreased with increasing bioburden. Young's modulus was greater in uninoculated controls compared to tendons inoculated at 10,000 CFU (p = 0.0011) but unaffected by bacterial concentrations of 100 and 1000 CFU (p = 0.054, p = 0.078). Increasing bioburden was associated with decreased peak load to failure (p = 0.043) but was most significant compared to the control under the 10,000 and 1000 CFU growth conditions (p = 0.0005, p = 0.049). The presence of S. epidermidis increased elasticity and decreased ultimate tensile stress of human cadaveric tendons, with increasing effect noted with increasing bioburden.

Tunnel Management in Revision Anterior Cruciate Ligament Reconstruction: Current Concepts

Bone tunnel-related complications are frequently encountered during revision anterior cruciate ligament reconstruction (ACLR). Issues with tunnel positioning, enlargement, containment, and hardware interference may complicate surgery and compromise outcomes. As a result, several strategies have emerged to address these issues and optimize results. However, a systematic, unified approach to tunnel pathology in revision ACLR is lacking. The purpose of this review is to highlight the current state of the literature on bone tunnel complications and, although extensive literature on the subject is lacking, present an updated approach to the evaluation and management of tunnel-related issues in revision ACLR.

The Addition of Either an Anterolateral Ligament Reconstruction or an Iliotibial Band Tenodesis Is Associated With a Lower Failure Rate After Revision Anterior Cruciate Ligament Reconstruction: A Retrospective Comparative Trial

PURPOSE

To compare the failure rate in patients who underwent revision anterior cruciate ligament (ACL) reconstruction alone or associated with an extra-articular procedure. Secondary objectives were to compare ACL laxity, patient-reported outcome measures, and complication rates in these patients and, subsequently, to compare the outcomes of patients who underwent revision ACL reconstruction associated with anatomical anterolateral ligament (ALL) reconstruction or lateral extra-articular tenodesis (LET).

METHODS

This was a retrospective comparative study. Patients were classified into 2 groups, according to whether (group 2) or not (group 1) an extra-articular reconstruction was performed. Patients who underwent an extra-articular procedure were further divided into ALL reconstruction (group 2A) and LET (group 2B). Baseline demographic variables, operative data and postoperative data were evaluated.

RESULTS

The groups with (86 patients) and without (88 patients) an associated extra-articular reconstruction had similar preoperative data. Group 2 had a lower failure rate (4.6% vs 14.7%; P = .038), better KT-1000, better pivot-shift, and better Lysholm. There was no difference regarding complications, except more lateral pain in group 2. Regarding the groups who underwent ALL reconstruction (41 patients) and LET (46 patients), group 2A showed better Lysholm scores. Both groups had similar failure rates and complications.

CONCLUSIONS

Patients who underwent revision ACL reconstruction with a laterally based augmentation procedure had a lower failure rate than patients who underwent isolated revision ACL reconstruction. KT-1000 and pivot-shift examination were also significantly better when a lateral augmentation was performed. Complications were similar except for an increase in lateral pain in the augmented group. No clinically important differences were found when comparing the LET group to the ALL group other than a statistical improvement in the Lysholm functional scale, likely not clinically meaningful, favoring the ALL group and an increased duration of post-operative lateral pain in the LET group.

LEVEL OF EVIDENCE

III, retrospective comparative therapeutic trial.

Allografts and lateral extra-articular tenodesis for revision anterior cruciate ligament reconstruction: enhanced rotational stability and improved functional outcomes

PURPOSE

Multiple studies have shown higher failure rate and patient-reported outcomes to be significantly worse following revision anterior cruciate ligament reconstructive (ACLR) surgery, especially using allografts. One of the reasons being rotational instability. Because of this, augmentation with lateral extra-articular tenodesis (LET) is often considered. Good short-term results in regards to functional and perceived scores and low complication rate can be expected in revision ACLR using allografts in combination with LET.

METHODS

Between 2014 and 2021, 46 patients were registered for revision ACLR using allografts and extra-articular augmentation (modified Lemaire) and included in this prospective study. Patients' demographic and clinical data were collected preoperatively, postoperatively, and during the follow-up period of 12 months.

RESULTS

Patient-reported functional outcomes were statistically significant for IKDC, Lysholm, and SF-12 physical scale (p < 0.05). Tegner score showed a decreased number of patients who were able to return to sport at their previous level (p = 0.001). Stability examination tests (Lachman and pivot-shift) showed significant improvements. Concomitant lesions were present in 76.1% of patients. Ten patients (21.7%) presented major complications, including six cases of anteroposterior instability, three cases of knee pain and one graft re-rupture.

CONCLUSION

Revision procedures are inherently challenging with a high number of associated chondral and meniscus lesions. However, good short-term functional outcomes and enhanced rotational stability with an acceptable complication rate can be expected in most cases where revision ACLR using allografts is augmented with LET.

STUDY DESIGN

Prospective; Case series; Level of evidence IV.

Double-bundle non-anatomic ACL revision reconstruction with allograft resulted in a low revision rate at 10 years

PURPOSE

This study aimed at reporting the long-term second revision rate and subjective clinical outcomes from a cohort of patients who underwent a double-bundle (DB) ACLR first revision with allograft at a single institution.

METHODS

The Institutional database was searched according to the following inclusion criteria: (1) patients that underwent DB-ACL first revision with Achilles tendon allograft, (2) surgery performed between January 2000 and December 2012, (3) age at revision ≥ 18 y/o. Patients' general information, history, surgical data, and personal contacts were extracted from charts. An online survey platform was implemented to collect responses via email. The survey questions included: date of surgeries, surgical data, date of graft failure and subsequent second ACL revision surgery, any other surgery of the index knee, contralateral ACLR, KOOS score, and Tegner scores.

RESULTS

Eighty-one patients were included in the survival analysis, mean age at revision 32 ± 9.2 y/o, 71 males, mean BMI 24.7 ± 2.7, mean time from ACL to revision 6.8 ± 5.4 years, mean follow-up time 10.7 ± 1.4 years. There were 12 (15%) second ACL revisions during the follow-up period, three females and nine males, at a mean of 4.5 ± 3 years after the index surgery. The overall survival rates were 85% from a second ACL revision and 68% from all reoperations of the index knee. Considering only the successful procedures (61 patients), at final follow-up, the mean values for the KOOS subscales were 84 ± 15.5 for Pain, 88.1 ± 13.6 for Symptoms, 93 ± 11.6 for ADL, 75 ± 24.5 for Sport, and 71 ± 19.6 for Qol. Twenty-nine (48%) patients performed sports activity at the same level as before ACLR failure.

CONCLUSIONS

Double-bundle ACL revision with fresh-frozen Achilles allograft yields satisfactory results at long-term follow-up, with an 85% survival rate from a second ACL revision at mean 10 years' follow-up and good patient-reported clinical scores.

LEVEL OF EVIDENCE

Level IV.

Conservative vs. Surgical Management for Femoro-Acetabular Impingement: A Systematic Review of Clinical Evidence

Femoro-acetabular impingement (FAI) syndrome is one of the most studied conditions in sports medicine. Surgical or conservative approaches can be proposed for treating FAI, although the best standard of care is not established yet. Our aim is to provide a comprehensive review of the best treatment for FAI syndrome evaluating differences in outcomes between surgical and non-operative management. A literature search was carried out on the PubMed, EMBASE, Scopus, and PEDro databases, using the following keywords: "femoroacetabular impingement", "FAI", in association with "surgery", "arthroscopy", "surgical" and "conservative", "physiotherapy", "physical therapy", "rehabilitation", "exercise". Only Level I RCTs were included. Four articles were selected for this systematic review. Our analysis showed different therapeutic protocols, follow-up periods, and outcomes; however, three out of the four studies included favored surgery. Our study demonstrates beneficial effects for both arthroscopic treatment and a proper regimen of physical therapy, nevertheless a surgical approach seemed to offer superior short-term results when compared to conservative care only. Further trials with larger sample sizes and longer follow-ups are needed to assess the definitive approach to the FAI condition.

Anterior Cruciate Ligament Revision Surgery Associated to Lateral Collateral and Anterolateral Ligaments Reconstruction With Single Achilles Tendon Allograft and Single Femoral Tunnel

Lateral collateral ligament (LC) injuries that go unnoticed when associated with an anterior cruciate ligament (ACL) tear can increase stress forces on the ACL graft causing its failure. Furthermore, it is a main stabilizer to varus stress and external rotation. On the other hand, the reinforcement of anterolateral structures during ACL reconstruction has regained popularity in recent years, because evidence has shown that it increases the control of rotational laxity and decreases ACL graft failures, especially in revision surgery. The present article shows a technique to perform an ACL reconstruction, associated with the reconstruction of the LCL and of the anterolateral ligament using a single Achilles tendon allograft, which is split after the fixation of the ACL graft into two fascicles.

Long-term functional outcomes of multiligament knee reconstructions with lateral injuries

INTRODUCTION

Multiligament knee injuries are a rare but serious injury, affecting functional prognosis. The objective of this study was to assess the long-term clinical and laximetric outcomes of acute or chronic multiligament knee reconstructions, with lateral impairment, using autografts.

HYPOTHESIS

Autograft reconstructions give good long-term clinical and laximetric results.

MATERIAL AND METHOD

A retrospective monocentric consecutive study was conducted in patients who had multiligament knee reconstructions. The criteria for inclusions were cruciate ligament lesions associated with lateral injuries, reconstructed using autografts, regardless of the time to surgery. A minimum follow-up of 5-years was required. Twenty-nine patients were analysed. The average age at surgery was 30.2±13 years. The patients were clinically reviewed at the last follow-up. Differential residual laxity was objectively assessed with comparative dynamic X-rays. Functional IKDC, Lysholm and KOOS scores were analyzed.

RESULTS

The average follow-up was 7.5±1.7 years. The lesions were divided into 12 KD-I, 16 KD-IIIL and 1 KD-IV, including 16 acute lesions (time to surgery <30-day) and 13 chronic lesions. At the last follow-up, the objective IKDC identified: 3 stage A, 15 stage B and 11 stage C. The average scores were: subjective IKDC 70.1±16, Lysholm 76.8±14 and KOOS: pain 71.6±20, symptoms 83.6±22, activity 90.6±20, sport 58.8±23, quality of life 60.0±30. Dynamic X-rays showed an average differential laxity of 2.8±2.6mm anteriorly, 5.0±2.2mm posteriorly, and 2.0±2.5mm in varus. Four cases required surgery: 3 arthrolysis procedures for stiffness and 1 joint lavage for sepsis.

DISCUSSION

With an average follow-up of 7.5 years, multiligament knee reconstructions using autografts with lateral involvement provide good long-term control of frontal and sagittal laxities. A comparison with allograft reconstructions is necessary to be able to potentially overcome the morbidity associated to donor sites.

LEVEL OF EVIDENCE

IV; monocentric retrospective descriptive study.

ACL autograft reconstruction revisions with tendon allografts: Possibilities and outcomes. A one-year follow-up of 39 patients

BACKGROUND

The number of anterior cruciate ligament (ACL) reconstructions is steadily rising in France. Re-tear rates of up to 25% have been reported and graft selection remains a notable challenge. Allografts, although rarely used in France, can be a viable option. The primary objective of this study was to demonstrate the benefits of ACL revision with allografts, by determining subjective scores (IKDC score and KOOS), measuring laxity, and evaluating the rate of return to sports.

HYPOTHESIS

Tendon allografts are reliable and can be used in France for ACL reconstruction revision.

MATERIAL AND METHODS

We conducted a retrospective study including 39 patients managed in two centres between 2004 and 2016 and followed up for at least a year. Patients were eligible if they had undergone tendon allograft reconstruction for ACL revision with or without rupture of a peripheral plane. We excluded underage patients and patients with a history of ligament injury in the contralateral knee. Mean age was 32 years. The allografts were extensor mechanisms, anterior or posterior tibial tendons, fascia lata tendons, hamstring tendons, and a short fibular tendon. They were obtained from French and Belgian tissue banks. They were used for the reconstruction of 39 ACLs and 11 collateral ligaments. The IKDC score and KOOS were determined in all patients. Laximetry was performed in 31 patients by an independent examiner.

RESULTS

Mean follow-up was 3.5 years. Arthroscopic release was required in one patient, and 2 patients experienced re-tears. No deep surgical site infections were recorded. The subjective IKDC score and the KOOS improved significantly, from 53.6 to 80.7 and from 60.4 to 83.2, respectively. Mean postoperative differential laxity was 1.4mm (KT 1000) and 1.6mm (GNRB®). Of the 3 patients who were professional athletes, 2 had returned to sports at the same level one year later, and among the recreational athletes, 54% had resumed their previous sporting activities.

CONCLUSION

In the setting of complex ligament reconstruction revision, tendon allografts are reliable and can be used in France.

LEVEL OF EVIDENCE

IV; retrospective cohort study.

Revision ACL reconstruction has higher incidence of 30-day hospital readmission, reoperation, and surgical complications relative to primary procedures

PURPOSE

Although there has been substantial improvement in ACL reconstructive surgery, graft failure remains a devastating complication for some patients. Revision procedures are inherently more complex and technically challenging. The purpose of this study is to determine the incidence of short-term complications after these procedures and to compare trends in operative length, relative valuation, and reimbursement after primary versus revision ACL reconstruction.

METHODS

Primary and revision arthroscopic ACL reconstruction cases were identified on the American College of Surgeons' NSQIP database using Current Procedural Terminology (CPT) and International Classification of Diseases (ICD) codes between January 1, 2012 and December 31, 2017. Demographics, patient variables, and surgical variables were compared between primary and revision groups using Chi-squared tests. Logistic regression was used to identify independent risk factors for revision ACL reconstruction. Various 30-day outcome measures were compared between the primary and revision ACL reconstruction groups. Various measures of valuation-including total relative value units (RVU) and reimbursement per minute-were calculated and compared between the two groups.

RESULTS

A total of 8292 patients-8135 primary and 157 revision procedures-were included in the final cohort. Higher ASA scores were associated with revision ACL reconstructions. Patients undergoing revision procedures were less likely to have an ASA score of 1 (p < 0.001) and more likely to have an ASA score of 2 (p = 0.004) or 3 (p = 0.020). Revision ACL reconstruction was associated with higher rates of poor 30-day outcome measures, including unplanned readmission (p = 0.029), reoperation (p = 0.012), return to the OR (p = 0.012), and surgical complications (p = 0.021). The total RVUs and reimbursement for revision procedures were significantly greater than those for primary procedures (p < 0.001). However, when accounting for operative time, the RVU/minute and reimbursement/minute were similar between the two groups (n.s.).

CONCLUSIONS

Relative to primary ACL reconstruction, revision ACL procedures are associated with worse short-term outcomes-including unplanned readmission, reoperation, return to the OR, and surgical complications. A greater ASA score was independently predictive of revision ACL surgery. The current RVU system undervalues revision ACL procedures, considering the increased operative time and complexity of such procedures.

LEVEL OF EVIDENCE

Level III.

Motor Imagery and Action Observation as Appropriate Strategies for Home-Based Rehabilitation: A Mini-Review Focusing on Improving Physical Function in Orthopedic Patients

Dynamic stability of the knee and weakness of the extensor muscles are considered to be the most important functional limitations after anterior cruciate ligament (ACL) injury, probably due to changes at the central (cortical and corticospinal) level of motor control rather than at the peripheral level. Despite general technological advances, fewer contraindicative surgical procedures, and extensive postoperative rehabilitation, up to 65% of patients fail to return to their preinjury level of sports, and only half were able to return to competitive sport. Later, it becomes clear that current rehabilitation after knee surgery is not sufficient to address the functional limitations after ACL reconstruction even years after surgery. Therefore, new therapeutic tools targeting the central neural system, i.e., the higher centers of motor control, should be investigated and integrated into current rehabilitation practice. To improve motor performance when overt movement cannot be fully performed (e.g., due to pain, impaired motor control, and/or joint immobilization), several techniques have been developed to increase physical and mental activation without the need to perform overt movements. Among the most popular cognitive techniques used to increase physical performance are motor imagery and action observation practices. This review, which examines the available evidence, presents the underlying mechanisms of the efficacy of cognitive interventions and provides guidelines for their use at home.

Current and future of anterior cruciate ligament reconstruction techniques

In recent years, anterior cruciate ligament (ACL) reconstruction has generally yielded favorable outcomes. However, ACL reconstruction has not provided satisfactory results in terms of the rate of returning to sports and prevention of osteoarthritis (OA) progression. In this paper, we outline current techniques for ACL reconstruction such as graft materials, double-bundle or single-bundle reconstruction, femoral tunnel drilling, all-inside technique, graft fixation, preservation of remnant, anterolateral ligament reconstruction, ACL repair, revision surgery, treatment for ACL injury with OA and problems, and discuss expected future trends. To enable many more orthopedic surgeons to achieve excellent ACL reconstruction outcomes with less invasive surgery, further studies aimed at improving surgical techniques are warranted. Further development of biological augmentation and robotic surgery technologies for ACL reconstruction is also required.

Aseptically Processed Allograft Implantation: A Safe Strategy for Knee Ligament Reconstructions

Postoperative infections after allograft implantation is a major concern in knee ligament reconstructions considering the theoretical risk of disease transmission and its potential severity. Here, we aimed to evaluate the postoperative infection rate after knee ligament reconstructions using aseptically processed allografts, and provide an overview of the allografts use in an academic tertiary hospital. A retrospective study was performed evaluating patients who underwent knee ligament reconstructions using aseptically processed allografts, including primary and revision surgeries, from 2005 to 2018. Demographic data, including the type of knee injury and trauma energy, and postoperative data were collected focusing on postoperative infections. Regarding these infected cases, further analyses were performed considering the presenting signs and symptoms, the isolated microorganism identified in culture, the time between graft implantation and diagnosis of infection (defined as acute, subacute, and late), and the need for graft removal. A total of 180 cases of ligament reconstructions were included. The mean follow-up was 8.2 (range: 2.1-15.6) years and the mean age at surgery was 34.1 (± 11.1) years. A total of 262 allografts were implanted in those 180 cases, 93 (35.5%) as bone plug allografts and 169 (64.5%) as soft tissue allografts. Common surgical indications included multiligament reconstruction (57.2%) and primary anterior cruciate ligament (ACL) reconstruction (15%). Seven cases (3.9%) presented postoperative infections. Knee pain (100%) and swelling (100%) were the most prevalent symptoms. Two cases (28.6%) presented sinus tract. Allografts were removed in two cases, the same cases that presented draining sinus (p = 0.04). High-energy trauma was the only statistically associated factor for infection (p = 0.04). No significant association between infection and the type of allograft (p > 0.99) or sex (p = 0.35) were observed. Four cases (57.1%) had monomicrobial staphylococcal infections. Based on that, the allograft-related infection rate was 1.7% (the remaining three infected cases). Nonirradiated, aseptically processed allografts have a low postoperative infection rate in knee ligament reconstructions, being a safe alternative for surgeries that require additional source, increased variety, and quantity of grafts.

Tendão quadricipital: Opção na reconstrução ligamentar do joelho

Although it is a versatile tendon, only 1% of surgeons choose to use the quadricipital tendon as a graft in anterior cruciate ligament (ACL) reconstruction. The present article aims to describe a quadricipital graft removal technique in which its deepest part is maintained. The technique consists of an approach in which the first incision is made in the medial part of the quadricipital tendon to prevent it from getting too short. This is due to its triangular design. The technique also addresses the depth and identification of the three layers of the quadricipital tendon so that it is possible to preserve its deepest part. This approach aims to preserve the extensor apparatus and to not communicate it with the joint environment, avoiding fluid extravasation both in the trans and postoperative periods.

Cellular Technologies in Traumatology: From Cells to Tissue Engineering

Injuries and degenerative changes of tendons are common damages of the musculoskeletal system. Due to its hypovascular character the tendon has a limited natural ability to recover. For typical surgical treatment, the tendon integrity is restored, but in most cases, there occurs formation of the connective tissue scar resulting in structural and mechanical functionality disruption. The insufficient effectiveness of traditional therapy methods requires the search for alternative ways to restore damaged tendon tissues. This article discusses new effective methods for improving the treatment that base on the use of cellular technologies among which one of the main directions is mesenchymal stem cell application. Due to mesenchymal stem cells, there is a shift from pro-fibrotic and pro-inflammatory reactions of cells to pro-regenerative ones. Stem cells being multipotent and having among other things tenogenic potential are considered a promising material for repairing damaged tendons. The article also describes the sources of progenitor tendon cells including the tendon bundles and pericytes the main markers of which are Scx and Mkx that are proteins of the transcription factor superfamily, and Tnmd that is transmembrane glycoprotein.

The growth factors that not only enhance the proliferative activity of mesenchymal stem cells but also promote in vitro tenogenic genes expression as well as the collagen Itype production what is necessary for tendon formation are considered. Along with growth factors, the morphogenetic protein BMP14 is presented, this protein increases themesenchymal stem cell proliferation and contributes directed tenogenic differentiation of these cells, suppressing their adipogenic and chondrogenic potentials.

In recent years, mesenchymal stem cells have been used both separately and in combination with various growth factors and different three-dimensional structures providing the interaction with all of the cell types.

The issues of the latest 3D-bioprinting technology allowing to make tissue-like structures for replacement damaged tissues and organs are discussed. 3D-bioprinting technology is known to allow acting exact spatio-temporal control of the distribution of cells, growth factors, small molecules, drugs and biologically active substances. 

Clinical outcome after knee ligament reconstruction with tendon allografts

PURPOSE

The purpose of this study is to investigate the clinical outcome for patients after knee ligament reconstructions with allografts at a university hospital.

METHODS

A total of 33 patients received allografts for reconstructive knee surgery between 2007 and 2017. The follow up evaluation consisted of a clinical knee examination including evaluation of range of motion (ROM), lateral and medial laxity, the Lachman test, the Pivot shift test, the sag test, the posterior drawer test and checking for patellofemoral pain. The following patient-reported outcome measures (PROMs) were used; the Lysholm Function Score, the Tegner activity score, and the Knee injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

Twenty-one (64%) patients were available for the follow-up evaluation and the mean follow-up time was 4.8 years. A total of 16 out of 21 patients had multiligament injuries of which the ACL was the ligament most frequently ruptured. At the time of follow-up, 14 out of 16 patients (87%) with ACL injury had Lachman test grade 0 or grade 1 + , and 12 out of 13 (92%) had a pivot shift grade 0 or 1 + . The mean Lysholm Score was 74. All mean KOOS subscale values were ≥ 59 at the follow-up. The preoperative Tegner activity score was 3 (range, 1-6) and 4 (range, 2-6) at follow up. There were no deep postoperative infections. A total of 19 out of 21 patients (90%) reported that they would have undergone surgery again had they known the clinical outcome in advance.

CONCLUSIONS

The patients improved from the preoperative score to the follow-up score in the knee-related Quality of Life (QoL) KOOS subscale. None of the patients were diagnosed with deep postoperative infections.

Lower incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction with quadriceps tendon compared to hamstring tendons

PURPOSE

To determine and compare the incidence of post-operative septic arthritis following revision anterior cruciate ligament reconstruction (R-ACLR) with autologous quadriceps tendon (with patellar bone block) compared to autologous hamstring tendons (semitendinosus and gracilis).

METHODS

A total of 1638 isolated R-ACLR with either autologous hamstring tendons (n = 1004, 61.3%) or quadriceps tendon (n = 634; 38.7%) were performed between 2004 and 2017 and were retrospectively analysed with regard to the occurrence of post-operative septic arthritis. The technique of R-ACLR did not significantly change during the years of the study. All patients received pre-op i.v.antibiotics, but no presoaking of the grafts in vancomycin was performed in the years of the study. The individual decision of graft choice was based on graft availability, tunnel position and the presence of tunnel widening. Generally, hamstring tendons were preferred. There were no clinically relevant differences between the groups regarding gender or age. Routine follow-up examination was performed 6 weeks after the index operation (follow-up rate 96.5%), and patients unsuspicious for septic arthritis at that time were classified as non-infected.

RESULTS

Fourteen patients with septic arthritis were identified, resulting in an overall incidence of 0.85%. There was one patient with septic arthritis in the quadriceps tendon group (incidence: 0.16%) and 13 patients in the hamstring tendons group (incidence: 1.29%), respectively. The difference was significant (p = 0.013).

CONCLUSION

In this series, the incidence of post-operative septic arthritis after R-ACLR was lower when quadriceps tendon graft was used compared to hamstring tendon grafts.

LEVEL OF EVIDENCE

III.

Comparison of concomitant injuries and patient-reported outcome in patients that have undergone both primary and revision ACL reconstruction-a national registry study

BACKGROUND

Anterior cruciate ligament (ACL) revision surgery has been associated with inferior outcome compared with primary ACL reconstruction. However, this has rarely been investigated in a consecutive cohort limited to patients that have undergone both primary and revision ACL reconstruction. This study aimed to assess differences in outcome and concomitant injuries between primary and revision ACL reconstruction in such a cohort, and to identify predictors of the patient-reported outcome after ACL revision.

METHODS

Patients who had undergone both primary and revision ACL reconstruction were identified in the Swedish National Knee Ligament Registry. Patients aged 13-49 years with hamstring tendon primary ACL reconstruction and data on the Knee Injury and Osteoarthritis Outcome Score (KOOS) on at least one occasion (preoperative or one year postoperatively) at both surgeries were eligible. Concomitant injuries and the KOOS were compared between each patient's primary and revision ACL reconstruction. Linear regression analyses were performed to determine predictors of the one-year KOOS after ACL revision.

RESULTS

A total of 1014 patients were included. Cartilage injuries increased at ACL revision (p < 0.001), as 23.0% had a cartilage injury at ACL revision that was not present at primary ACL reconstruction. The 1-year KOOS was lower after ACL revision compared with primary ACL reconstruction, with the largest difference in the KOOS sports and recreation (5.2 points, SD 32.2, p = 0.002). A posterolateral corner (PLC) injury at ACL revision was a negative predictor of KOOS, with the largest effect on the sports and recreation subscale (β = - 29.20 [95% CI - 50.71; - 6.69], p = 0.011). The use of allograft for ACL revision was an independent predictor of a poorer KOOS QoL (β = - 12.69 [95% CI - 21.84; - 3.55], p = 0.0066) and KOOS₄ (β = - 11.40 [95% CI - 19.24; - 3.57], p = 0.0044).

CONCLUSION

Patients undergoing ACL revision reported a 1-year outcome that was slightly inferior to the 1-year outcome after their primary ACL reconstruction. An ACL revision was associated with an increase in cartilage injuries. A PLC injury at ACL revision and the use of allograft for ACL revision predicted a clinically relevant poorer KOOS one year after ACL revision.

Editorial Commentary: Bone Tunnel Grafting for Two-Stage Anterior Cruciate Ligament Revision and the Meaning of Life for an Arthroscopic Surgeon

Accurate bone tunnel filling in a 2-staged anterior cruciate ligament revision is indubitably fundamental for a successful outcome. Bone autograft is commonly employed and it is usually harvested from the iliac crest: this requires longer surgical time, and donor-site morbidity following bone harvest is a well-known problem. Therefore, strategies to minimize or abolish it have been attempted: the use of allografts may seem promising, but their use is associated with high costs and strict regulatory limitations. Bony substitutes instead represent a new and potentially effective solution: they could help surgeons to fill bone tunnels in an easier and faster way that elicits satisfactory lamellar bone formation within the tunnels, and their use is associated with fewer postoperative complications, such as pain and local hematoma. Evidence from literature suggests that this approach could provide significant advantages over traditional autograft harvesting, with comparable outcomes in terms of bone formation and integration, allowing a correct tunnel placement during revision surgery.

Outcomes Following ACL Reconstruction Based on Graft Type: Are all Grafts Equivalent?

PURPOSE OF REVIEW

Anterior cruciate ligament reconstruction is one of the most common orthopedic procedures performed, accounting for over 200,000 cases annually. Despite the high prevalence, there is still much debate as to the optimal graft choice. The purpose of this review is to evaluate the current literature and discuss the reported outcomes for the most common graft choices.

RECENT FINDINGS

The most common autografts being used include bone-patellar tendon-bone (BPTB), hamstring tendon (HT), and quadriceps tendon (QT). Hamstring tendon might have a slightly higher re-tear rate when compared with BPTB (2.84 versus 2.80). However, BPTB has a higher rate of anterior knee and kneeling pain in the short- and mid-term follow-up. This has not been shown to be the case in long-term follow-up. Allograft is a viable option for revisions and primaries in patients greater than 35 years old; however, re-tear rate increases significantly in younger patients. ACL reconstruction graft choice is a highly studied and yet still exceedingly debated topic. Most large studies report either no significant difference or a small difference in failure rate and outcome scores between the different autograft choices. Allografts have been demonstrated to have an increased risk of failure in younger athletes and should be reserved for revision cases and those aged 35 years and older. Graft choice should ultimately be decided upon based on surgeon comfort and experience and individual patient characteristics.

Stem Cell-Infused Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) tears are unfortunate but common injuries in the athletic population. The standard of care for ACL tears is a surgical intervention to reconstruct the ACL to restore knee functionality as well as quality of life. In recent years, bone marrow aspirate concentrate (BMAC) has seen increasing use in various orthopaedic settings. This increase can be attributed to the potential beneficial qualities that mesenchymal stem cells, progenitor cells, and growth factors, all of which are present in BMAC, can provide. In this technical note and accompanying video, we describe an anatomic allograft ACL reconstruction infused with BMAC to utilize BMAC's potential benefits.

Outcome After Anterior Cruciate Ligament Revision

PURPOSE OF REVIEW

To describe the current literature related to anterior cruciate ligament (ACL) revision in terms of surgical aspects, graft choices, concomitant injuries, patient-reported outcome, return to sport, and objective measurement outcome.

RECENT FINDINGS

An ACL rupture is a common knee injury, and the number of primary ACL reconstructions is increasing, implying a subsequent increase of ACL revisions in the future. It is widely accepted that an ACL revision is surgically challenging with a myriad of graft options to choose from. In many cases, simultaneous injuries to the index limb including meniscal and chondral lesions, respectively, are observed in the setting of a secondary ACL injury. Furthermore, the general understanding is that an ACL revision results in inferior outcome compared with a primary ACL reconstruction. Surgical treatment of an ACL revision can be performed as one-stage or two-stage procedure depending on, for example, the presence of limb malalignments, concomitant injuries, and tunnel widening. Nonirradiated allografts and autologous patella tendon, hamstring tendon, and quadriceps tendon are feasible options for ACL revision. Concomitant injuries to the affected knee such as intraarticular chondral lesions are more common in the setting of an ACL revision compared with primary ACL reconstruction while a lower presence of concomitant meniscal pathology is reported at ACL revision. Patients undergoing ACL revision have lower clinical and patient-reported outcome and lower rates of return to sport when compared with primary ACL surgery cases. However, long-term follow-ups with large study cohorts evaluating outcome of ACL revision are limited. Further research is needed to confirm the present findings of this review.