Editorial Commentary: Quadriceps Tendon Is a Better Graft Than Hamstring for Anterior Cruciate Ligament Reconstruction

Over the last 12 years identification of specific risk factors (age, activity level, and laxity) for failure of anterior cruciate ligament (ACL) reconstruction have led to comparisons of the patellar tendon (PT) and hamstring (HS) tendon grafts. The PT has proved superior in most of these studies. During this same time period, there has been increased clinical/research interest in the quadriceps tendon autograft for ACL reconstruction. This has led to direct comparison to the HS and QT autografts. Again, the HS tendon appears inferior in measured outcomes to the quadriceps tendon. Increased laxity measurements seem to correlate with the decreased evidence of radiographic healing on magnetic resonance imaging. If this is the case, it may indeed be the final nail in the coffin for HS graft use in young at-risk athletic populations.

Unsupervised Machine Learning of the Combined Danish and Norwegian Knee Ligament Registers: Identification of 5 Distinct Patient Groups With Differing ACL Revision Rates

BACKGROUND

Most clinical machine learning applications use a supervised learning approach using labeled variables. In contrast, unsupervised learning enables pattern detection without a prespecified outcome.

PURPOSE/HYPOTHESIS

The purpose of this study was to apply unsupervised learning to the combined Danish and Norwegian knee ligament register (KLR) with the goal of detecting distinct subgroups. It was hypothesized that resulting groups would have differing rates of subsequent anterior cruciate ligament reconstruction (ACLR) revision.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

K-prototypes clustering was performed on the complete case KLR data. After performing the unsupervised learning analysis, the authors defined clinically relevant characteristics of each cluster using variable summaries, surgeons' domain knowledge, and Shapley Additive exPlanations analysis.

RESULTS

Five clusters were identified. Cluster 1 (revision rate, 9.9%) patients were young (mean age, 22 years; SD, 6 years), received hamstring tendon (HT) autograft (91%), and had lower baseline Knee injury and Osteoarthritis Outcome Score (KOOS) Sport and Recreation (Sports) scores (mean, 25.0; SD, 15.6). Cluster 2 (revision rate, 6.9%) patients received HT autograft (89%) and had higher baseline KOOS Sports scores (mean, 67.2; SD, 16.5). Cluster 3 (revision rate, 4.7%) patients received bone-patellar tendon-bone (BPTB) or quadriceps tendon (QT) autograft (94%) and had higher baseline KOOS Sports scores (mean, 65.8; SD, 16.4). Cluster 4 (revision rate, 4.1%) patients received BPTB or QT autograft (88%) and had low baseline KOOS Sports scores (mean, 20.5; SD, 14.0). Cluster 5 (revision rate, 3.1%) patients were older (mean age, 42 years; SD, 7 years), received HT autograft (89%), and had low baseline KOOS Sports scores (mean, 23.4; SD, 17.6).

CONCLUSION

Unsupervised learning identified 5 distinct KLR patient subgroups and each grouping was associated with a unique ACLR revision rate. Patients can be approximately classified into 1 of the 5 clusters based on only 3 variables: age, graft choice (HT, BPTB, or QT autograft), and preoperative KOOS Sports subscale score. If externally validated, the resulting groupings may enable quick risk stratification for future patients undergoing ACLR in the clinical setting. Patients in cluster 1 are considered high risk (9.9%), cluster 2 patients medium risk (6.9%), and patients in clusters 3 to 5 low risk (3.1%-4.7%) for revision ACLR.

Randomized Controlled Trials Comparing Bone-Patellar Tendon-Bone Versus Hamstring Tendon Autografts in Anterior Cruciate Ligament Reconstruction Surgery Are Statistically Fragile: A Systematic Review

PURPOSE

To assess the statistical fragility of recently published randomized controlled trials (RCTs) comparing the use of hamstring tendon autograft with bone-patellar tendon-bone autograft for anterior cruciate ligament (ACL) reconstruction.

METHODS

The PubMed, Embase, and MEDLINE databases were queried for RCTs published since 2010 comparing autograft type (bone-patellar tendon-bone vs hamstring tendon) in ACL reconstruction surgery. The fragility index (FI) and reverse FI (rFI) were determined for significant and nonsignificant outcomes, respectively, as the number of outcome reversals required to change statistical significance. The fragility quotient (FQ) and reverse FQ, representing fragility as a proportion of the study population, were calculated by dividing the FI and rFI, respectively, by the sample size.

RESULTS

We identified 19 RCTs reporting 55 total dichotomous outcomes. The median FI of the 55 total outcomes was 5 (interquartile range [IQR], 4-7), meaning a median of 5 outcome event reversals would alter the outcomes' significance. Five outcomes were reported as statistically significant with a median FI of 4 (IQR, 2-6), meaning a median of 4 outcome event reversals would change outcomes to be nonsignificant. Fifty outcomes were reported as nonsignificant with a median rFI of 5 (IQR, 4-7), meaning a median of 5 outcome event reversals would change outcomes to be significant. The FQ and reverse FQ for significant and nonsignificant outcomes were 0.025 (IQR, 0.018-0.045) and 0.082 (IQR, 0.041-0.106), respectively. For 61.8% of outcomes, patients lost to follow-up exceeded the corresponding FI or rFI.

CONCLUSIONS

There is substantial statistical fragility in recent RCTs on autograft choice in ACL reconstruction surgery given that altering a few outcome events is sufficient to reverse study findings. For over half of outcomes, maintaining patients lost to follow-up may have been sufficient to reverse study conclusions.

CLINICAL RELEVANCE

We recommend co-reporting FIs and P values to provide a more comprehensive representation of a study's conclusions when conducting an RCT.

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.

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.

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.

Graft choices for paediatric anterior cruciate ligament reconstruction: State of the art

The paediatric population is at particularly high risk for anterior cruciate ligament (ACL) injuries due to high rates of sports participation. Other risk factors for ACL injuries in children include but are not limited to being female, generalised ligamentous laxity, a high body mass index (BMI), and poor neuromuscular control. ACL reconstruction (ACLR) is commonly done to treat ACL injuries and allow for return to sports and daily activities. ACL repair is another option with ongoing techniques being developed. The high rates of graft failure in children reported in recent publications on ACL repair are very concerning. Special consideration must be taken in ACLR in the skeletally immature patient due to the risk of growth-related complications, such as limb deformity or growth arrest, that can arise from drilling across or disrupting the physis. Graft choices for paediatric ACLR include iliotibial band (ITB) over the top and over the front, hamstring autograft, bone patellar tendon bone (BTB) autograft, quadriceps tendon autograft, and allograft. Factors for each graft choice to consider include graft size, graft failure rates, donor site morbidity, requirement for bony tunnels, the post-op rehabilitation process, and return to sport outcomes. Each graft has its benefits and disadvantages for the individual patient, depending on age, skeletal maturity, and goals for recovery. Lateral extra-articular tenodesis (LET) is another option to consider with paediatric ACLR because LET has been shown to decrease the re-rupture rate in adult ACLR. After surgery, patient follow-up until at least the growth plates are closed is important. This article aims to provide an overview and comparison of the various graft types to aid in the graft choice decision making process for paediatric ACLR.

Revision ACL reconstruction using quadriceps, hamstring and patellar tendon autografts leads to similar functional outcomes but hamstring graft has a higher tendency of graft failure

PURPOSE

The purpose of this study was to evaluate the differences in the patient-reported functional outcomes, and graft failure in revision ACL reconstruction using quadriceps tendon (QT), Hamstring tendon (HT) and bone-patellar tendon-bone (BPTB) autografts.

METHODS

Between 2010 and 2020, 97 patients who underwent revision ACL reconstruction (40 patients received a QT, 26 an HT and 31 a BPTB graft) met the inclusion criteria. Pre-injury and at 2-year postoperatively patients were evaluated for patient-reported functional outcomes; Lysholm knee score, Tegner activity level and VAS (visual analogue scale) for pain; and graft failure. Patient-reported outcomes and graft failure were compared between the QT, HT and BPTB groups. The patients with graft failure were not included for outcome analysis at 2-years of follow-up.

RESULTS

All three revision groups with QT, HT and BPTB autograft did not differ significantly in terms of age, sex, time from injury to surgery, concomitant injuries and single-stage or double-stage procedures (n.s.). No significant difference was found in the pre-injury patient-reported outcome; Lysholm knee score, Tegner activity and VAS for pain (n.s.) between the three groups. At the 2-year follow-up functional outcomes improved in all three groups and all the patients returned to pre-injury activity level; however, no significant difference was found in functional outcomes at the 2-year follow-up between the three groups (n.s.). Graft failure occurred in 4 (10%), 5 (19%) and 3 (10%) patients of QT, HT and BPTB groups, respectively. However, the rate of failure did not differ significantly between groups.

CONCLUSION

All three autografts (QT, HT and BPTB) demonstrated satisfactory patient-reported outcomes in revision ACL reconstruction. Compared with QT and BPTB grafts, HT graft showed a higher tendency for failure rates. With the increasing incidence of revision ACL reconstruction, surgeons should be aware of all the available graft options. The findings of this study will assist the surgeons in the graft selection for revision ACL reconstruction.

LEVEL OF EVIDENCE

Level III.

Differences in collagen types in the semitendinosus, quadriceps, and patellar tendons: A report using samples from an 11-year-old patient

BACKGROUND

This study aimed to determine the differences in the proportions of types I and type III collagen in the semitendinosus tendon (ST), quadriceps tendon (QT), and patellar tendon (PT), which are frequently used as autografts for anterior cruciate ligament (ACL) reconstruction.

METHODS

Orthopedic surgeons diagnosed habitual dislocation of the left patella and surgically treated an 11-year-old boy. Medial patellofemoral ligament reconstruction, medial patellar tibial ligament reconstruction, and arthroscopic lateral release were performed simultaneously. Tissue samples obtained during treatment that were no longer necessary were used as samples for this study. The samples were fixed, paraffin-embedded, and immunostained for type I and type III collagen. Stained samples were observed under a confocal microscope and evaluated visually and quantitatively to determine the percentages of type I and type III collagen.

RESULTS

Visually, the ST had a higher percentage of type III collagen than the PT and QT. The QT and PT were similar in appearance; both consisted mostly of collagen type I. Quantitative evaluation using images showed that the PT comprised 100% type I collagen. The QT comprised 1% type III collagen. The ST comprised 34% type III collagen.

CONCLUSION

In this patient, the QT and PT had higher percentages of type I collagen, which is considered physically strong. Type III collagen, which is considered physically weak, was most common in the ST. These factors may be associated with the high re-injury rates after ACL reconstruction using the ST for physically immature patients.

Hamstring, bone-patellar tendon-bone, quadriceps and peroneus longus tendon autografts for primary isolated posterior cruciate ligament reconstruction: a systematic review

INTRODUCTION

Several autografts are available to reconstruct the posterior cruciate ligament (PCL).

SOURCE OF DATA

Current scientific literature published in PubMed, Google scholar, Embase and Scopus.

AREAS OF AGREEMENT

Hamstring, bone-patellar tendon-bone (BPTB), quadriceps and peroneus longus (PLT) are the most common tendon autografts used for primary isolated PCL reconstruction.

AREAS OF CONTROVERSY

The optimal tendon source for PCL reconstruction remains nevertheless debated. Identifying the most suitable tendon autograft could assist the surgeon during primary PCL reconstruction.

GROWING POINTS

The present study compared the outcome of PCL reconstruction using hamstring, BPTB, quadriceps and PLT autografts. The focus was on patient-reported outcome measures (PROMs), joint laxity, range of motion and complications.

AREAS TIMELY FOR DEVELOPING RESEARCH

All autografts are viable options for PCL reconstruction, with BTB and hamstring autografts demonstrating superior PROMs. However, further clinical investigations are required to determine the ideal autograft construct.

Management of Patella Fracture Nonunion and Large Bone Defect After Bone-Patellar Tendon-Bone Autograft: A Case Report

CASE

A 32-year-old patient was diagnosed with a vertical patella fracture nonunion after a bone-patellar tendon-bone (BTB) anterior cruciate ligament reconstruction. In addition, a 1 × 2 × 1 cm patellar bone defect was noticed at the graft harvesting site. The patient was treated surgically with open reduction and internal fixation and iliac crest bone autograft which resulted in fracture union.

CONCLUSION

Many intraoperative and postoperative risk factors for iatrogenic patella fracture when harvesting BTB autograft were identified. Surgeons should be aware of technical skills needed to prevent this complication and should treat the fracture appropriately to avoid nonunion and optimize the outcome.

A Comparison of Quadriceps Tendon Autograft With Bone-Patellar Tendon-Bone Autograft and Hamstring Tendon Autograft for Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review and Quantitative Synthesis

OBJECTIVE

There is growing enthusiasm for the increased use of quadriceps tendon (QT) autograft for primary anterior cruciate ligament reconstruction (ACLR). The purpose of this analysis was to synthesize and quantitatively assess the available evidence comparing QT autograft with hamstring tendon (HT) and bone-patellar tendon-bone (BPTB) autografts, regarding functional outcomes, knee stability, anterior knee pain, and revision rates.

DATA SOURCES

A search in MEDLINE, EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials for eligible studies up to May 2018 was conducted. Two reviewers selected studies based on inclusion criteria and assessed methodological quality. Outcomes analyzed were anterior knee pain, graft failure rates, knee stability, functional outcomes, and adverse events. Pooled analyses were performed for continuous and dichotomous variables where appropriate.

MAIN RESULTS

Ten studies (1 randomized trial and 9 nonrandomized cohorts) met our inclusion criteria, which included 1398 patients. The analysis showed no statistical difference in anterior knee pain when comparing QT and HT autografts, but a significant difference between QT and BPTB autografts [odds ratio, 0.15 (95% confidence interval, 0.08-0.27); P < 0.001]. There were no differences between all 3 autografts in revision rates, knee stability, and patient-reported functional outcomes.

CONCLUSIONS

Quadriceps tendon autograft is a suitable graft alternative for primary ACLR, as it achieves good clinical outcomes with a low incidence of anterior knee pain. Given the limited quality of the included studies, there is a need for a well-designed multicenter randomized control trial comparing QT autograft with other primary ACL autografts to confirm our findings.

LEVEL OF EVIDENCE

Level IV systematic review.

A novel approach for optimal graft positioning and tensioning in anterior cruciate ligament reconstructive surgery based on the finite element modeling technique

BACKGROUND

In ACL-reconstructed patients the postoperative knee biomechanics may differ from the intact knee biomechanical behavior which can alter knee kinematics and kinetics, and as a result lead to the progression of knee osteoarthritis. The aim of this study was to demonstrate the potential of finite element models to define the optimal choices in surgical parameters in terms of optimal graft positioning in combination with graft type in order to restore the kinematic and kinetic behavior of the knee as best as possible.

METHODS

A workflow was proposed based on cadaveric experiments in order to restore the injured knee to a near normal physiological condition. Femoral and tibial graft insertion sites and graft fixation tension were optimized to obtain similar intact knee laxity, for three common single-bundle and one double-bundle reconstructions. To verify the success of the surgery with the variables calculated using the proposed workflow, a full walking cycle was simulated with the intact, ACL-ruptured, optimal ACL-reconstructed and non-optimal reconstructed knees.

RESULTS

Our results suggested that for patellar tendon and hamstring tendon grafts, anatomical positioning (fixation force: 40 N), and for quadriceps tendon graft, isometric positioning (fixation tension: 85 N) could recover the intact joint kinematics and kinetics. Also for double-bundle reconstruction, with the numerically calculated optimal insertion sites, both bundles needed 50-N fixation force.

CONCLUSIONS

With optimal graft positioning parameters, following the proposed workflow in this study, any of the single-bundle graft types and surgical techniques (single vs. double-bundle) may be used to acceptably recover the intact knee joint biomechanical behavior.

Quadriceps tendon vs. patellar tendon autograft for ACL reconstruction using a hardware-free press-fit fixation technique: comparable stability, function and return-to-sport level but less donor site morbidity in athletes after 10 years

INTRODUCTION

The use of quadriceps tendon-patellar bone (QTB) autograft for anterior cruciate ligament (ACL) reconstruction is gaining momentum. Yet, long-term results that compare this procedure with established methods are lacking. The aim of this study was to report and compare long-term results of ACL reconstruction using QTB autografts versus bone-patellar tendon-bone (BPTB) autografts, both anchored using a hardware-free press-fit fixation technique.

MATERIALS AND METHODS

60 athletes (Tegner score ≥6) with primary ACL rupture were prospectively randomized into two groups. 56 patients were evaluated after a mean duration of 12.2 ± 1.9 months (range 10-14) and 43 patients after 10.3 ± 0.2 years (range 10-11).

RESULTS

On final follow-up, 90% of patients scored very good and good results in the functional Lysholm score (mean 99 ± 7.1, range 74-100 points). Normal or almost normal IKDC score was reported by 84% of the patients (mean 97 ± 9.5, range 60-100 points). The activity level decreased in the Tegner score from median of 7 before injury to 6 after 10 years. The KT-1000 arthrometer showed a difference in the anterior translation of less than 3 mm (mean 1.0 ± 1.2, range - 1 to 5 mm) in 91% of the patients. Significant degeneration was radiologically detected in one patient per group. No tunnel widening was seen in any patient. Up to 97% of all patients were satisfied with the operative procedure. No significant differences were found in the mentioned parameters between the two groups and also in comparison with the 1-year results. The only significant difference was in the donor site morbidity. Significantly more patients in the BPTB group had complaints during kneeling both at 1 (p < 0.001) and 10 years (p = 0.019). Squatting was also subjectively more problematic in the BPTB group than in the QTB group both after 1 (p = 0.003) and 10 years (p = 0.046).

CONCLUSIONS

This study shows equally good functional, clinical and radiological long-term results for both hardware-free methods of ACL reconstruction. These results clinically confirm the safety of press-fit anchoring after 10 years. The failure rate in this study was very low, with only one re-rupture in 10 years. The increased donor site morbidity when using the BPTB autograft compared to the QTB autograft supports already reported data. It was also seen in this study for the implant-free press-fit techniques.

STUDY DESIGN

Prospective and randomized, level of evidence 2.

Influence of operative technique on anterior cruciate ligament reconstruction in patients older than 50 years

BACKGROUND

A consequence of the steady growth in the worldwide population of elderly individuals who remain in good health and continue to engage in sports is an increase in the incidence of anterior cruciate ligament (ACL) rupture occurring after 50 years of age. ACL reconstruction was formerly reserved for young athletes but now seems to produce good outcomes in over 50s. The type of graft and graft fixation method were selected empirically until now, given the absence of investigations into potential relationships of these two parameters with the outcomes. The objective of this study was to assess associations linking the type of graft and the method of femoral graft fixation to outcomes in patients older than 50 years at ACL reconstruction.

HYPOTHESIS

The operative technique is not associated with the clinical outcomes or differential laxity.

MATERIAL AND METHODS

A multicentre retrospective cohort of 398 patients operated between 1 January 2011 and 31 December 2015 and a multicentre prospective cohort of 228 patients operated between 1 January 2016 and 30 June 2017 were conducted. Mean follow-up was 42.7 months in the retrospective cohort and 14.2 months in the prospective cohort. The primary evaluation criterion was the clinical outcome as assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Tegner Activity Score (TAS). Differential laxity was the secondary evaluation criterion. The Wilcoxon rank sum test and Kruskal-Wallis test were used to compare groups, and p-values<0.05 were considered significant.

RESULTS

In the retrospective and prospective cohorts, hamstring tendons were used in 269 (67.6%) and 197 (86.4%) patients and extensor apparatus tendons in 124 (31.2%) and 31 (13.6%) patients. Femoral fixation in the retrospective cohort was cortical in 81 (20.4%) cases, by press-fit in 112 (28.1%) cases, and by interference screw in 205 (51.5%) cases; corresponding figures in the prospective cohort were 135 (59.2%), 17 (7.5%), and 76 (33.3%). The multivariate analysis of the retrospective data identified no significant associations of graft type or femoral fixation type with the KOOS, TAS, or differential laxity values. In the prospective cohort, hamstring grafts were associated with 0.6mm of additional laxity (p=0.007); compared to cortical fixation, press-fit fixation of patellar tendon grafts was associated with 0.3mm of additional laxity (p=0.029) and a 0.5-point lower TAS value (p=0.033), with no difference in KOOS values. None of these differences were clinically significant.

DISCUSSION

The various ACL reconstruction techniques used in patients older than 50 years produce similar outcomes. The technique can be chosen based on surgeon preference without regard for patient age.

LEVEL OF EVIDENCE

IV.

Comparison of drop jump landing biomechanics and asymmetry among adolescents with hamstring, patellar and quadriceps tendon autografts for anterior cruciate ligament reconstruction

BACKGROUND

Adolescent anterior cruciate ligament reconstruction (ACLR) commonly utilizes hamstring (HT), patellar (PT) or quadriceps (QT) tendon autografts, but consensus is lacking regarding optimal graft choice. This study compared landing biomechanics and asymmetries among ACLR patients with HT, PT and QT grafts and uninjured controls.

METHODS

This retrospective study included 61 adolescents with unilateral ACLR (27 HT, 20 PT, 14 QT; four to 12 months post-surgery, mean 6.4; age 15.4, SD 1.4 years) and 27 controls (14.6, SD 0.9 years) who were evaluated during drop jump landings. Lower extremity 3D biomechanics and asymmetries were compared.

RESULTS

Compared to controls, all operative limbs exhibited 1) greater hip flexion and lower dorsiflexion angles; 2) higher hip and lower knee and ankle flexion moments; 3) higher energy absorption at the hip (HT and QT only) and lower at the knee and ankle; and 4) higher knee abduction moments. Asymmetries observed in all ACLR groups included 1) lower knee and ankle flexion angles; 2) lower knee and ankle flexion moments; 3) lower energy absorption at the knee and ankle; and 4) higher hip and knee abduction moments on the operative side. The PT and QT groups demonstrated greater asymmetry in hip and knee flexion moments compared to HT.

CONCLUSIONS

While adolescent ACLR limbs offloaded the knee and ankle, patients with PT or QT grafts demonstrated greater deficiencies during rehabilitation than those reconstructed with HT. Graft choice in ACLR should remain patient-specific and aim to optimize biomechanics with the ultimate goal of minimizing graft re-tear and donor site morbidity.

Pediatric Anterior Cruciate Ligament Reconstruction

The rate of anterior cruciate ligament (ACL) ruptures diagnosed among the pediatric and adolescent population is increasing. The rise in ACL injuries may be attributed to earlier sports specialization, year-round sports participation, increased awareness, and improved ability to diagnose the injury. Treatment options for pediatric or adolescent ACL injuries include nonoperative conservative treatment, ACL repair, or various techniques for ACL reconstruction. The best course of treatment for ACL rupture in young patients continues to be debated. Anterior cruciate ligament reconstruction with autograft is currently the gold standard and has been shown to be successful in restoring joint stability. This article reviews predisposing factors, common mechanisms, diagnostic procedures, and treatments for ACL rupture in adolescent patients, with a focus on using quadriceps patellar tendon autograft. [Orthopedics. 2018; 41(3):129-134.].

Sex Differences in the Residual Patellar Tendon After Harvesting Its Central Third for Anterior Cruciate Ligament Reconstruction

OBJECTIVES

Some studies have found that sex can affect the clinical results after anterior cruciate ligament reconstruction. We hypothesized that sex would significantly affect the healing of the postoperative patellar tendon. This study evaluated the patellar tendon after bone-patellar tendon-bone autograft harvest, specifically with regard to sex-dependent differences.

METHODS

At 6 months postoperatively, an ultrasonographic evaluation was performed. We measured the residual donor site gap width between tendon tissues and the thickness of newly formed nontendinous tissue in the gap. In addition, the cross-sectional area of tendon tissue was measured. The ratios between the operated and contralateral sides were calculated, and the sexes were compared. A paired Student t test was performed, with P < .05 considered statistically significant.

RESULTS

The population of 52 patients (32 male and 20 female) had a mean age ± SD of 23 ± 8 years. We observed no significant sex-dependent differences in the residual donor site gap and the thickness of newly formed nontendinous tissue when calculating ratios to the contralateral tendon. The mean cross-sectional area of tendon tissue was 101 ± 26 mm² (male, 114 ± 26 mm² ; female, 80 ± 16 mm² ). When the ratios to the contralateral tendon were calculated, male patients had significantly higher cross-sectional area ratios than female patients (male, 124% ± 20%; female, 100% ± 19%, P = .024).

CONCLUSIONS

We have reported a dramatic increase in the cross-sectional area of patellar tendon tissue during the first 6 months after anterior cruciate ligament reconstruction with a bone-patellar tendon-bone autograft, which was more prominent in male patients than in female patients. This difference might have contributed to the sex-dependent variation in clinical outcomes.

Comparative Study of Patellar Tendon Graft versus Hamstrings Graft for Anterior Cruciate Ligament Reconstruction

Graft selection for primary anterior cruciate ligament reconstruction is very important part of knee stability. The purpose of this Qasi experimental study was to compare the clinical outcomes after ACL reconstruction using either a BPTB graft or a four-strand hamstrings graft and conducted from January 2012 to December 2013. Patients presented with a symptomatic unilateral ACL rupture who were underwent ACL reconstruction by using either BPTB or Hamstrings graft, IPD of Department of Orthopedics at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka as well as in a private hospital in Dhaka, Bangladesh were selected as study population. Patients were divided into Group A who were treated with the patellar tendon bone graft and Group B patients who were received hamstrings tendon graft. All surgery was performed by the same surgeon and the both procedures were arthroscopically assisted. Operation was performed at least three (03) weeks after initial trauma. All patients were assessed by independent examiner before surgery, at 6 months, 12 months and then annually by clinically. A total number of 70 patients were recruited for this study. The mean age with SD of Group A and Group B were 27.31±10.91 and 26.97±10.10 years respectively (p=0.892). Tegner scores were measured preoperatively and post-operatively. The score were 2.2±1.1 and 2.1±1.0 in preoperatively (p=0.817). In post-operatively the mean score were 6.0±1.7 and 5.8±1.5 in Group A and Group B respectively (p=0.508). Regarding outcome of the operation excellent was 18(51%) cases in both Group A and Group B, good was 15 (43%) and 16(46%) cases in Group A and Group B respectively (p=0.793). In conclusion there was no significant difference between the two groups of the ACL reconstructions cases.

Do peak torque angles of muscles change following anterior cruciate ligament reconstruction using hamstring or patellar tendon graft?

OBJECTIVES

This study aims to compare the effects of anterior cruciate ligament (ACL) reconstruction using autogenous hamstring or patellar tendon graft on the peak torque angle.

PATIENTS AND METHODS

The study included 132 patients (103 males, 29 females; mean age 29±9 year) who were performed ACL reconstruction with autogenous hamstring or patellar tendon graft. The peak torque angles in the quadriceps and hamstring muscles were recorded using an isokinetic dynamometer.

RESULTS

Angle of peak knee flexion torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the hamstring tendon group. Angle of peak knee extension torque occurred significantly earlier within the range of motion on the operated side than nonoperated side at 180°/second in the patellar tendon group. There were no statistically significant differences in the flexion and extension peak torque angles between the operated and nonoperated knees at 60°/second in both groups.

CONCLUSION

The angle of peak torque at relatively high angular velocities is affected after ACL reconstruction in patients with hamstring or patellar tendon grafts. The graft donor site directly influences this parameter. This finding may be important for clinicians in terms of preventing re-injury.

Anatomic single-bundle anterior cruciate ligament reconstruction improves walking economy: hamstrings tendon versus patellar tendon grafts

PURPOSE

Anterior cruciate ligament (ACL) injury is associated with a pathologic gait pattern and increased energy cost during locomotion. ACL reconstruction could improve the gait pattern. Hamstrings tendon (HAM) and bone-patellar tendon-bone (BPTB) grafts are usually used for reconstruction. The aim of this study was to compare the efficacy of anatomic ACL reconstruction with HAM and BPTB grafts on improving and normalizing the energy cost and physiologic reserves during flat, uphill, and downhill walking.

METHODS

Twenty male subjects with unilateral ACL injuries were randomly assigned to ACL reconstruction with a HAM (n = 10) or BPTB (n = 10) graft. Ten matched controls were also enrolled. All participants performed three 8-min walking tasks at 0, +10, and -10 % gradients before and 9 months after surgery. Energy cost (oxygen consumption, VO₂), heart rate (HR), and ventilation (VE) were measured. Lysholm/IKDC scores were recorded.

RESULTS

Pre-operatively, VO₂, HR, and VE were higher in the HAM and BPTB groups than in controls during walking at 0, +10, and -10 % gradients (p < 0.001-0.01). Post-operatively, both HAM and BPTB groups showed reduced VO₂, HR, and VE during the three walking tasks (p < 0.001-0.01). Although the post-operative VO₂ in both surgical groups reached 90-95 % of the normative (control) value during walking, it remained elevated against the value observed in controls (p < 0.001-0.01). The HAM and BPTB groups showed no differences in post-surgical VO₂ or HR during walking at all three gradients.

CONCLUSION

Anatomic ACL reconstruction with either HAM or BPTB graft resulted in similar short-term improvements in energy cost and nearly normalized locomotion economy and cardiorespiratory reserves during flat, uphill, and downhill walking. The improved locomotion economy is an additional benefit of anatomic ACL reconstruction, irrespective of the type of graft used, that the orthopaedic surgeons should consider.

LEVEL OF EVIDENCE

II.

Mechanical Analysis of Extra-Articular Knee Ligaments. Part two: Tendon grafts used for knee ligament reconstruction

OBJECTIVES

The aim of this study was to provide information about the mechanical properties of grafts used for knee ligament reconstructions and to compare those results with the mechanical properties of native knee ligaments.

METHODS

Eleven cadaveric knees were dissected for the semitendinosus, gracilis, iliotibial band (ITB), quadriceps and patellar tendon. Uniaxial testing to failure was performed using a standardized method and mechanical properties (elastic modulus, ultimate stress, ultimate strain, strain energy density) were determined.

RESULTS

The elastic modulus of the gracilis tendon (1458±476MPa) (P<0.001) and the semitendinosus tendon (1036±312MPa) (P<0.05) was significantly higher than the ITB (610±171MPa), quadriceps tendon (568±194MPa), and patellar tendon (417±107MPa). In addition, the ultimate stress of the hamstring tendons (gracilis 155.0±30.7MPa and semitendinosus 120.1±30.0MPa) was significantly higher (P<0.001, respectively P<0.05), relative to the ITB (75.0±11.8MPa), quadriceps tendon (81.0±27.6MPa), and patellar tendon (76.2±25.1MPa). A significant difference (P<0.05) could be noticed between the ultimate strain of the patellar tendon (24.6±5.9%) and the hamstrings (gracilis 14.5±3.1% and semitendinosus 17.0±4.0%). No significant difference in strain energy density between the grafts was observed.

CONCLUSIONS

Material properties of common grafts used for knee ligament reconstructions often differ significantly from the original knee ligament which the graft is supposed to emulate.

Changes in patella tendon length over 5 years after different types of knee arthroplasty

PURPOSE

Post-operative shortening of the patellar tendon resulting in an abnormally low-lying patella has been described previously, but the degree of change in patella tendon length over time and extent of its progression after different types of knee arthroplasties remains unknown. This study assesses the incidence of patella tendon length change following lateral unicompartmental knee arthroplasty (UKA), medial UKA, and total knee arthroplasty (TKA), and its impact on patient-reported outcome at 5 years post-surgery.

METHODS

Immediate post-operative, 1- and 5-year radiographs were reviewed for 50 patients undergoing each operation (n = 150), with the Insall-Salvati ratio used as a measure of patella tendon length. Clinical outcome was assessed using the Oxford Knee Score (OKS).

RESULTS

At 5-year follow-up, no significant change in patella tendon length was found following medial UKA (1.07-1.05), whilst a significant shortening was found after TKA (1.02-0.96), and a significant lengthening found after lateral UKA (1.02-1.05). For the UKA groups, no further change in tendon length was observed after the first year post-surgery, whereas the TKA group continued to shorten between years one and five. OKS was significantly better in the UKA groups as compared to TKA group. Change in patella tendon length within individual groups did not correlate with OKS at 5 years.

CONCLUSION

Patella tendon length shortening is more prevalent in TKAs, whilst lengthening is more prevalent in lateral UKAs. Despite the vertical incision through the patella tendon, lateral UKAs do not cause increased tendon shortening at 5 years post-surgery. However, in the medium term, changes in patella tendon length do not affect patient-reported outcome.

LEVEL OF EVIDENCE

Retrospective, comparative study, Level III.

A Randomized Controlled Trial With Mean 16-Year Follow-up Comparing Hamstring and Patellar Tendon Autografts in Anterior Cruciate Ligament Reconstruction

BACKGROUND

There is no consensus in the current literature on which surgical options render the best long-term results after anterior cruciate ligament (ACL) reconstruction in terms of clinical outcomes and the development of radiographic osteoarthritis (OA).

PURPOSE

To investigate the long-term clinical and radiographic results after ACL reconstruction using either a patellar tendon (PT) autograft or a hamstring tendon (HT) autograft.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 2.

METHODS

This multicenter study was based on 2 previous randomized cohorts consisting of 193 patients who underwent unilateral primary ACL reconstruction using either a PT autograft or an HT autograft. The index surgical procedure was performed between September 1995 and January 2000. Clinical assessments, including knee laxity measurements, functional outcomes, patient-reported outcomes, and bilateral standing radiographs, were performed at the final follow-up examination.

RESULTS

At the long-term follow-up, 147 (76%) patients were examined: 61 in the PT group and 86 in the HT group. The mean (±SD) follow-up time was 191.9 ±15.1 months for the HT group and 202.6 ± 10.4 months for the PT group. Knee laxity measurements revealed significantly more patients with a normal pivot-shift test finding in the HT group compared with the PT group (71% vs 51%, respectively; P = .048); however, no significant differences were found in terms of the manual Lachman test or the KT-1000 arthrometer manual maximum test. The patients in the PT group had significantly more difficulty knee walking (P = .049). There were no significant differences between the study groups in terms of patient-reported outcomes or range of motion in the reconstructed knee. In both groups, significantly more signs of radiographic OA were found in the reconstructed knee than in the contralateral healthy knee. However, there were no significant differences between the groups in terms of radiographic OA.

CONCLUSION

Only minor and mostly insignificant differences were found between the PT and HT autograft groups in this long-term randomized controlled trial. In both groups, significantly more signs of radiographic OA were found in the reconstructed knee than in the contralateral knee.

Bioabsorbable versus metallic interference screws for graft fixation in anterior cruciate ligament reconstruction

BACKGROUND

Anterior cruciate ligament (ACL) tears are frequently treated with surgical reconstruction with grafts, frequently patella tendon or hamstrings. Interference screws are often used to secure the graft in bone tunnels in the femur and tibia. This review examines whether bioabsorbable interference screws give better results than metal interference screws when used for graft fixation in ACL reconstruction.

OBJECTIVES

To assess the effects (benefits and harms) of bioabsorbable versus metallic interference screws for graft fixation in ACL reconstruction.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, CENTRAL (the Cochrane Library), MEDLINE, Embase, LILACS, trial registers and reference lists of articles. Date of search: January 2016.

SELECTION CRITERIA

We included randomised controlled trials and quasi-randomised trials comparing bioabsorbable with metallic interferences screws in ACL reconstruction. The main outcomes sought were subjective-rated knee function, failure of treatment, and activity level.

DATA COLLECTION AND ANALYSIS

At least two review authors selected eligible trials, independently assessed risk of bias, and cross-checked data. Data were pooled whenever relevant and possible. Requests for further information were sent to the original study authors.

MAIN RESULTS

We included 12 trials (11 randomised and one quasi-randomised) involving a total of 944 participants, and reporting follow-up results for 774. Participants in the 12 trials underwent ACL reconstruction with either hamstring tendon grafts (five trials) or patellar tendon grafts (seven trials). Trials participants were randomly allocated to bioabsorbable or metallic interference screws for graft fixation in both femur and tibia (seven trials); femur only (three trials); tibia only (one trial); location was not reported in the remaining trial. A variety of materials was used for the bioabsorbable screws, Poly-L-lactic acid (PLLA) being the most common. The metallic screws, where reported, were titanium.All trials were at high risk of bias, which invariably included performance bias. Seven trials were at high risk of attrition bias and eight at high risk of reporting bias. The quasi-randomised trial was assessed as being at high risk for selection bias. Based on these study limitations and insufficiency of the available data, we judged the quality of evidence for all outcomes was very low.The majority of the available data for patient-reported knee function was presented as Lysholm scores (0 to 100; higher scores = better function). There was very low quality but consistent evidence of no clinically important differences between the two groups in Lysholm scores at 12 months follow-up (mean difference (MD) -0.08, 95% confidence interval (CI) -1.48 to 1.32; three trials, 168 participants); 24 months (MD 0.35, 95% CI -1.27 to 1.98; three trials, 113 participants) or five or more years follow-up (MD 1.23, 95% CI -2.00 to 4.47; two trials, 71 participants). This lack of between-group differences was also reported for Lysholm scores in several trials that did not provide sufficient data for pooling as well as for other self-reported knee function scores reported in several trials.Treatment failure was represented by the summed data for implant breakage during surgery and major postoperative complications (implant failure, graft rupture, symptomatic foreign body reactions, effusion and treated arthrofibrosis and related conditions) that were usually described in the trial reports as requiring further substantive treatment. There is very low-quality evidence of greater treatment failure in the bioabsorbable screw group (60/451 versus 29/434; risk ratio (RR) 1.94 favouring metallic screw fixation, 95% CI 1.29 to 2.93; 885 participants, 11 studies). In a population with an assumed risk (based on the median control group risk) of 56 participants per 1000 having treatment failure after metallic screw fixation, this equates to 53 more (95% CI 17 to 108 more) per 1000 participants having treatment failure after bioabsorbable screw fixation. All 16 intraoperative complications in the bioabsorbable screw group were implant breakages upon screw insertion. Treatment failure defined as postoperative complications only still favoured the metallic screw group but the 95% CI also included the potential for a greater risk of treatment failure after metallic screw fixation: 44/451 versus 29/434; RR 1.44, 95% CI 0.93 to 2.23. Based on the assumed risk of 56 participants per 1000 having postoperative treatment failure after metallic screw fixation, this equates to 25 more (95% CI 4 fewer and 69 more) per 1000 participants having this outcome after bioabsorbable screw fixation.There was very low-quality evidence of very similar activity levels in the two groups at 12 and 24 months follow-up measured via the Tegner score (0 to 10; higher scores = greater activity): 12 months (MD 0.08, 95% CI -0.39 to 0.55; 122 participants, two studies); 24 months (MD 0.01, 95% CI -0.54 to 0.57; 72 participants, two studies).

AUTHORS' CONCLUSIONS

There is very low-quality evidence of no difference in self-reported knee function and levels of activity between bioabsorbable and metallic interference screws for graft fixation in ACL reconstruction. There is very low-quality evidence that bioabsorbable screws may be associated with more overall treatment failures, including implant breakage during surgery. Further research does not appear to be a priority, but if undertaken, should also examine costs.

Stepwise Differentiation of Mesenchymal Stem Cells Augments Tendon-Like Tissue Formation and Defect Repair In Vivo

: Tendon injuries are common and present a clinical challenge, as they often respond poorly to treatment and result in long-term functional impairment. Inferior tendon healing responses are mainly attributed to insufficient or failed tenogenesis. The main objective of this study was to establish an efficient approach to induce tenogenesis of bone marrow-derived mesenchymal stem cells (BMSCs), which are the most common seed cells in tendon tissue engineering. First, representative reported tenogenic growth factors were used as media supplementation to induce BMSC differentiation, and the expression of teno-lineage transcription factors and matrix proteins was compared. We found that transforming growth factor (TGF)-β1 significantly induced teno-lineage-specific gene scleraxis expression and collagen production. TGF-β1 combined with connective tissue growth factor (CTGF) elevated tenomodulin and Egr1 expression at day 7. Hence, a stepwise tenogenic differentiation approach was established by first using TGF-β1 stimulation, followed by combination with CTGF for another 7 days. Gene expression analysis showed that this stepwise protocol initiated and maintained highly efficient tenogenesis of BMSCs. Finally, regarding in situ rat patellar tendon repair, tendons treated with induced tenogenic BMSCs had better structural and mechanical properties than those of the control group, as evidenced by histological scoring, collagen I and tenomodulin immunohistochemical staining, and tendon mechanical testing. Collectively, these findings demonstrate a reliable and practical strategy of inducing tenogenesis of BMSCs for tendon regeneration and may enhance the effectiveness of cell therapy in treating tendon disorders.

SIGNIFICANCE

The present study investigated the efficiency of representative tenogenic factors on mesenchymal stem cells' tenogenic differentiation and established an optimized stepwise tenogenic differentiation approach to commit tendon lineage differentiation for functional tissue regeneration. The reliable tenogenic differentiation approach for stem cells not only serves as a platform for further studies of underlying molecular mechanisms but also can be used to enhance cell therapy outcome in treating tendon disorders and develop novel therapeutics for tendon injury.

No significant difference in clinical outcome and knee stability between patellar tendon and semitendinosus tendon in anterior cruciate ligament reconstruction

INTRODUCTION

ACL reconstruction with either patellar tendon or semitendinosus tendon autografts are standard procedures. Between these two grafts might be differences in stability, morbidity, or long-term changes. This study investigates outcomes of ACL reconstruction with patellar tendon versus semitendinosus tendon autografts. We hypothesize no significant differences in clinical outcome and knee stability between both groups.

METHODS

In a randomized prospective trial, we operated 62 ACL-deficient patients, 45 males and 17 females with a mean age of 29.8 years (min. 18, max. 44). We reconstructed the ligament using either autologous patellar tendon (n = 31) or semitendinosus tendon (n = 31). After 10 years of follow-up, we investigated 47 patients of the study. For evaluation we used a standard clinical examination including one-leg jump test and KT-1000 instrumental translation measure, visual analog pain scale, IKDC subjective knee form, Lysholm score, Tegner activity scale, and standard X-rays of the knee.

RESULTS

The data did not show any significant differences between the two groups. Between 5 and 10 years after ACL reconstruction both groups started to develop degenerative arthritic changes, which were detectable in standard radiographs of the knee. At 10-year follow-up mean IKDC for the BPTB group was 1.8 (min. 1, max. 3) and for the ST group it was 2.2 (min 1, max. 4), p = 0.35. Regarding Tegner activity scale after 10 years, the BPTB group showed a mean score of 5.9 (min. 4, max. 9) versus 5.1 (min. 3, max. 7) in the ST group, p = 0.53. For the Lysholm score the BPTB group reached a mean of 92.0 (min. 63, max. 98) and the ST group 91.8 (min. 62, max. 98) points, p = 0.66. There is a tendency for higher donor site morbidity in the BPTB group than in the ST group, p = 0.07.

CONCLUSIONS

Both, patellar tendon and semitendinosus tendon are safe autografts for ACL reconstruction. Regarding graft selection, individual patient-dependent factors should be considered. ACL reconstruction cannot fully restore pre-injury status of knee joint function in the majority of cases.

Orthopedic Practice Patterns Relating to Anterior Cruciate Ligament Reconstruction in Elite Athletes

We conducted an online survey of National Hockey League (NHL), Major League Soccer (MLS), and US Olympic/World Cup Ski/Snowboard (Olympic) team orthopedic surgeons to determine practice patterns relating to anterior cruciate ligament (ACL) reconstruction in elite athletes. Of the 94 team orthopedic surgeons surveyed, 47 (50%) responded. Mean (SD) experience as a team physician was 7.73 (5.33) years for NHL, 6.77 (6.64) years for MLS, and 1.14 (0.36) years for Olympic. Mean (SD) number of ACL reconstructions performed in 2012 was 101 (51) for NHL, 78 (38) for MLS, and 110 (105) for Olympic. Overall, 33 surgeons (70.2%) indicated they would use bone-patellar tendon-bone (BPTB) autograft to treat their starting athletes. Twenty-one (44.7%) drilled the femoral tunnel through a transtibial portal, 36.2% through an anteromedial portal, and 12.8% by a 2-incision technique. All the surgeons used a single-bundle technique. Thirty-three (70.2%) did not recommend a brace for their elite athletes during play on return to sport (RTS). Twenty-seven NHL and MLS surgeons (81.8%) recommended RTS only after an athlete has passed a series of RTS tests (eg, Vail, single-leg hop). Most of the NHL, MLS, and Olympic team orthopedic surgeons who were surveyed perform their ACL reconstructions using BPTB autograft, using a single-bundle technique, and through a transtibial portal, and do not require bracing for their athletes returning to sport. Most required their athletes to complete a series of RTS tests before resuming competitive play.

Knee extensor mechanism allograft reconstruction following chronic disruption

The management of chronic extensor mechanism disruption can be complex. One of the options is allograft reconstruction. The goal of this study was to present the surgical procedure and provide preliminary results with this technique. The allograft uses the whole extensor mechanism (anterior tibial tubercle, patellar ligament, patella, quadriceps tendon). The native patella can be completely removed if the quality of the bone is poor, otherwise a bone groovecan be created to receive the allograft. The allograft is tightly tensioned with the knee in full extension. This surgical technique was performed 5 times with a minimum follow-up of 1 year. Active extension was recovered in all cases. The mean postoperative KOOS was 55.5 the IKS function score was 68.5 and the IKS knee score was 83.

Analysis of biomechanical properties of patellar ligament graft and quadruple hamstring tendon graft

INTRODUCTION

Two types of transplant are commonly used in the surgical management of anterior cruciate ligament lesions: the central part of the patellar ligament and quadruple tendons of the gracilis muscle and semitendinosus muscle.

AIMS

The aim of this study was to determine the biomechanical characteristics of patellar ligament transplants and transplants of the quadruple tendons of the hamstring muscles under tensile force in the laboratory, and to compare the results in each group of samples.

MATERIALS AND METHODS

The study comprised 160 specimens: 40 specimens of gracilis muscle tendons, 40 of semitendinosus muscle tendons, 40 of quadruple tendons and 40 of the patellar ligament, approximately equally distributed according to sex, age (50-70 years) and the side of the body from which the specimen had been taken.

RESULTS

The working curve analysis of the specimens under tensile load of a maximum force of 30N showed the least elongation (0.31%) in the quadruple tendon, followed by the gracilis muscle tendon (1.48%) and patellar ligament tendon (3.91%).

CONCLUSIONS

The quadruple tendon specimen showed greater strength and higher elasticity compared with the patellar ligament specimen, which proved the starting hypothesis.

Quadrupled Hamstring Graft Strength as a Function of Clinical Sizing

PURPOSE

This study sought to compare the strength of quadrupled hamstring tendon (QHT) grafts of 6 to 9.5 mm in clinical diameter with that of 10-mm bone-patellar tendon-bone (BPTB) grafts.

METHODS

Twenty cadaveric semitendinosus and gracilis tendons were combined into QHT grafts. These were sized using a standard graft-sizing device and an area micrometer, yielding grafts ranging from 6 to 9.5 mm in diameter. The grafts were tested to failure. Five 10-mm BPTB grafts were also sized and tested.

RESULTS

Clinical sizing did predict the strength of the graft but not profoundly. As a material alone, without consideration of fixation in bone tunnels, QHT grafts were stronger than BPTB grafts. Graft strength decreased with size, but a linear relation between strength and diameter (r(2) = 0.715, P < .001) was found to be as good as the expected quadratic fit (r(2) = 0.709). Compared with BPTB grafts, even the smallest QHT grafts (diameter <6.5 mm) were still significantly stronger than 10-mm BPTB grafts (P = .004). The elastic moduli of the QHT and BPTB grafts were 761 ± 187 MPa and 615 ± 403 MPa, respectively; elongations at failure were 12.0% ± 2.0% and 7.5% ± 1.6%, respectively; and failure stresses were 105 ± 18 MPa and 50 ± 14 MPa, respectively.

CONCLUSIONS

This work shows that a clinical size of QHT grafts of 6 mm in diameter is not a concern regarding the strength itself. For a possible lower-end prediction of acceptable size, assuming that a gracilis-semitendinosus graft would have only the stress of the weakest measured QHT graft of 88 MPa, a graft of 5.5 mm in diameter would suffice, having more strength in newtons than the average patellar tendon.

CLINICAL RELEVANCE

Clinically sized QHT grafts have a higher failure strength than 10-mm patellar tendon grafts. Therefore the strength of the graft cannot account for the higher clinical failure rates of smaller hamstring grafts in active patients in clinical studies.

[Long-term outcomes after "anatomic" reconstruction of anterior cruciate ligament using central third of patellar tendon]

Reconstruction of the anterior cruciate ligament (ACL) is one of the most commonly performed procedures in orthopedics.

AIM

The aim of the study was to evaluate long-term results of anterior cruciate ligament reconstruction using middle third patellar tendon grafts.

MATERIALS AND METHODS

The study included 29 patients with an average 8 years follow - up. All patients underwent arthroscopic reconstruction of ACL using the central third of the patellar tendon ligament. The grafts attachment points were determined by using the Howell pointer. The average patient age was 36 years (range from 16 to 48 years). Postoperative assessment was based on the modified Lysholm score, intensity of the degenerative changes in the Lawrence-Kellgren scale and stabilometric measurments of the knee by Rolimeter and Telos Stress Device.

RESULTS

According to the Lyscholm score 21 of 29 patients achieved good and very good result, 7 sufficient, and one case was reported as a bad result. Most of the unsatisfactory results were related with coexisting intraarticular injuries: meniscus and articular cartilage lesions. Outcomes of stabilometric measurments was strongly correlated with subjective results of survey.

CONCLUSIONS

In spite evolution of techniques and the introduction of new methods of ACL reconstruction, treatments performed several years ago using the BPTB transtibial technique was possible to obtain good results of treatment.

Regional mechanical properties of human patellar tendon allografts

PURPOSE

Very little is known regarding regional biomechanical properties of patellar tendon allografts.

METHODS

Ten human bone-tendon-bone (BTB) patellar grafts were separated into equal thirds and underwent cyclic and failure testing. Grafts were non-irradiated and processed using proprietary sterilization methods.

RESULTS

The central third was the thickest region (4.9 ± 0.4 mm) compared to the medial and lateral (p < 0.05). The lateral third was the longest region (58.8 ± 8.8 mm) compared to the medial (47.9 ± 8.5 mm) and central (47.2 ± 8.8 mm) portions (p < 0.05). Cyclic testing demonstrated no regional differences with respect to elongation (n.s.) and creep strain (n.s.). Failure testing demonstrated increased maximum load and stiffness in the central region (1,680 ± 418 N and 278 ± 67 N/mm, respectively) as compared to the medial (1,033 ± 214 N, p < 0.002, 201 ± 37 N/mm, p < 0.03) and lateral thirds (908 ± 412 N, p < 0.03, 173 ± 66 N/mm, p < 0.002). Elongation at maximum load did not vary between regions. Central region maximum stress (41.0 ± 12.5 MPa) was greater than that of the medial third (28.1 ± 3.6 MPa, p < 0.02), with strain at maximum stress larger in the central third (0.21 ± 0.03) compared to lateral (0.16 ± 0.03, p < 0.01).

CONCLUSIONS

The central third of a non-irradiated, human bone-patellar tendon-bone construct is thicker and biomechanically superior to the medial and lateral regions in most respects. These findings reinforce the use of the central third of a patellar tendon allograft in anterior cruciate ligament reconstruction. Further investigations are required to determine whether the decreased biomechanical properties of the medial and lateral third of the BTB construct negatively influence the mechanical function of hemi-BTB grafts.

Meniscal transplantation: still experimental surgery? A review

INTRODUCTION

The objective of this review is to give a state of affairs of meniscal transplantation, with the accent on preservation and surgical techniques.

MATERIALS AND METHODS

All articles were selected by performing a search on the literature by using relevant keywords. The most relevant articles were selected with close attention to the publication date.

RESULTS

When a meniscal tear is diagnosed, suture can be an option in the vascular zone, whereas the more frequently affected avascular zone heals poorly. A meniscectomy however is not without consequences, wherefore meniscal transplantation can be seen as a therapeutic option for pain reduction and improvement of function when the meniscus is lost. The meniscal scaffold, allograft and autograft can be currently withheld as possible grafts, where the meniscal scaffolds hold great promise as an alternative to the allograft. Various fixation techniques are therefore developed, where viable, deep frozen as well as cryopreservated allografts seem to give the most promising short term results. The transplantation can be performed using an open as well as an arthroscopic technique, using soft tissue fixation, bone plugs or blocks. De primacy of one technique can't be proven. In general meniscal transplantation can be considered as an acceptable procedure.

DISCUSSION

Since the outcomes of different studies are difficult to compare, an attempt should be made to limit new studies to the comparison of one aspect. We can conclude that larger, more comparative randomised controlled long-term studies are necessary to resolve which techniques can give the best long-term results.

Insall-Salvati ratio after arthroscopic anterior cruciate ligament reconstruction with patellar tendon graft

BACKGROUND

Arthroscopic anterior cruciate ligament (ACL) reconstruction with patellar tendon graft has been considered to be the gold standard treatment of anterior cruciate ligament injuries. Much morbidity could occur after this graft was harvested, such as the patellar tendon length change and anterior knee pain. Insall-Salvati ratio is one of the tools to determine the patella tendon length.

OBJECTIVE

To study the patella tendon length change after arthroscopic ACL reconstruction with patellar tendon graft by using Insall-Salvati ratio.

MATERIAL AND METHOD

Descriptive study was conducted. Patients who were diagnosed ACL injury and underwent arthroscopic ACL reconstruction with patellar tendon graft were included. All patients had standardized preoperative and postoperative lateral knee radiographs. The patellar tendon length, patellar height, Insall-Salvati ratio and Tegner Lysholm knee score were measured by the same person for all subjects at preoperative and 6 months postoperative period.

RESULTS

In a series of 22 patients, the length of the patellar tendon lengthened by an average of 0.95 mm (6 mm shortening to 5 mm lengthening) or 1.82% and not statistically significant (p = 0.101). The Insall-Salvati ratio increased by 2.75% (16.32% shortening to 18.6% lengthening) which was also not statistically significant (p = 0.218). The Tegner Lysholm knee score was improved to 20.36 (5 to 45), which was statistically significant (p < 0.05). The amount of the Insall-Salvati ratio change was not related to Lysholm score (p = 0.571).

CONCLUSION

The present study indicated that there was no significant change of patellar tendon length after arthroscopic ACL reconstruction with patellar tendon graft. No correlations with postoperative Insall-Salvati ratio and Tegner Lysholm knee score, however, the clinical results was improved in all of the patients.

Reconstructive surgery using autologous bone-patellar tendon graft for insertional Achilles tendinopathy

PURPOSE

The purpose of this study was to investigate the clinical results of reconstructive surgery using a bone-patellar tendon (BPT) autograft for athletes with intractable insertional Achilles tendinopathy.

METHODS

Ten athletes who underwent reconstructive surgery using a BPT autograft were included in this study. Indications were (1) persistent symptoms in spite of conservative therapy for 6 months, and (2) diffuse high intensity changes of an entire cross-section of the tendon at its insertion point on T2-weighted magnetic resonance imaging (MRI), with clinical follow-up of more than 24 months after surgery. Clinical evaluation was performed before surgery and at the most recent follow-up [median: 32 (25-48) months], and radiological assessment at 1 year after surgery.

RESULTS

The median Achilles tendon rupture score at the most recent follow-up was 92.5 (85-100) points. The median visual analogue scale score improved significantly from 90 (85-100) points preoperatively to 5 (0-10) points at the most recent follow-up (P < 0.01). Based on T2-weighted MRI, the anterior-posterior width of the grafted BPT was approximately twice that of the intact nonsurgical contralateral tendon insertion in all patients at 1 year after surgery. The median time from surgery to ability to return to full sports activity was 13.5 months.

CONCLUSIONS

The reconstructive surgery presented in this study can be useful for athletes who suffer from insertional Achilles tendinopathy with a wide area of diseased tendon at the insertion point.

LEVEL OF EVIDENCE

IV.

Tear patterns, surgical repair, and clinical outcomes of patellar tendon ruptures after anterior cruciate ligament reconstruction with a bone-patellar tendon-bone autograft

BACKGROUND

Patellar tendon ruptures are rare after graft harvest for anterior cruciate ligament (ACL) reconstruction. Few reports are available in the literature.

PURPOSE

To report the common tear patterns and results of treatment with tendon repair and cable augmentation.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All tendon ruptures were repaired to bone with suture anchors and augmented with a Dall-Miles cable, followed by an aggressive rehabilitation protocol. The tear location was recorded. Range of motion, strength, and subjective survey testing were conducted preoperatively and postoperatively.

RESULTS

Thirteen patellar tendon ruptures were found from our database of 5364 ACL reconstructions, for an incidence of 0.24%. Seven ruptures occurred from the patellar origin medially and the tibial attachment laterally in a Z-shaped pattern. Four were completely distal, and 2 were completely proximal ruptures. All patients exhibited early flexion loss, but 11 of 13 patients maintained full, terminal hyperextension throughout treatment. The mean postoperative side-to-side flexion deficit was 33° at 1 month, 6° at 3 months, and 3° at latest follow-up at a mean of 4.8 years after tendon repair (range, 1-16 years). By International Knee Documentation Committee (IKDC) criteria, 10 patients had normal flexion, and 3 were nearly normal at latest follow-up. Twelve patients had normal extension, and 1 had nearly normal extension at latest follow-up. Mean isokinetic quadriceps muscle strength was 68.7% of the other side at 3 months after repair and 100.0% at latest follow-up, occurring at a mean of 47.5 months (range, 12-120 months). At a mean of 2 years (range, 1-4 years) after repair, the mean modified Noyes subjective score was 89.8 ± 9.2.

CONCLUSION

Patellar tendon ruptures are rare after ACL graft harvest. These ruptures usually occur in either a proximal-medial and distal-lateral pattern or an entirely distal pattern, in contrast to the proximal-only tear pattern commonly observed in unharvested patellar tendons. Good objective and subjective results were achieved with repair of postoperative patellar tendon ruptures using suture anchors and Dall-Miles cable augmentation, followed by aggressive, immediate range of motion exercises.

Crimp frequency is strongly correlated to myofibroblast density in the human anterior cruciate ligament and its autologous tendon grafts

PURPOSE

Collagen crimp is essential for maintaining viscoelastic properties of normal ligament and tendon tissue. The actin isoform α-smooth muscle actin (ASMA) has been identified in fibroblastic cells of these tissues. These highly differentiated cells, so-called myofibroblasts may transmit tensile forces to the extracellular matrix, thus it has been suggested that they are responsible for the wrinkling of the extracellular matrix and the formation of crimp. During anterior cruciate ligament (ACL) graft remodeling, crimp formation plays an integral role. Thus, it was our purpose to determine the relationship between myofibroblast density and crimp frequency in human tendon graft tissue and the ACL.

METHODS

Different tendon grafts and ACLs were harvested from young human multi-organ donors immediately after death. Myofibroblasts were immunostained with a monoclonal antibody, and histomorphometry was performed using a digital imaging system. Crimp length was measured, and data were correlated.

RESULTS

All tendons and ACLs showed a significant correlation of myofibroblast density and crimp frequency (R(2) 0.81-0.43). The strongest correlation was found for the patellar tendon, the poorest for the gracilis tendon. There is also evidence that the phenotype respectively the shape of myofibroblasts might be responsible for different stages of crimp formation.

CONCLUSION

With the present investigation, we found that myofibroblasts might be involved in crimp formation and should be viewed as an integral part of normal tendon and ligament tissue. Furthermore, the shape of myofibroblasts may further indicate the contractile potency of the extracellular matrix, thus presenting a dynamic and variable crimp rather than a static situation. This study is an experimental study. In terms of clinical relevance all the mentioned tendons can be used as auto- or allografts for ACL reconstruction, nevertheless their microscopic structure and cellular population have yet not been adequately investigated and compared.

Results of the surgical reconstruction of the anterior cruciate ligament

Results of the surgical reconstruction of the anterior cruciate ligament (ACL), using as a graft fourfold hamstring tendons (gracilis and semitendinosus) and middle third of the patellar ligament, were compared. In all patients that were participating in this study clinical examination and magnetic resonance showed ACL rupture, and apart from the choice of the graft, surgical technique was identical. We evaluated 112 patients with implemented patellar ligament graft and fourfold hamstring tendons graft six months after the procedure. Both groups were similar according to age, sex, activity level, knee instability level and rehabilitation program. The results showed that there was no significant difference between groups regarding Lysholm Knee score, IKDC 2000 score, activity level, musculature hypotrophy, and knee joint stability 6 months after the surgery. Anterior knee pain incidence is significantly higher in the group with patellar ligament graft (44% vs. 21%). Both groups had a significant musculature hypotrophy of the upper leg of the knee joint that was surgically treated, six months after the procedure. Both grafts showed good subjective and objective results.

Neurocognitive rehabilitative approach effectiveness after anterior cruciate ligament reconstruction with patellar tendon. A randomized controlled trial

BACKGROUND

A proper knee rehabilitation after a surgical reconstruction of the anterior cruciate ligament (ACL) should start immediately after the injury and it should be focused on recovery of symmetry, proprioception, swelling reduction, gait training, hyperextension exercises, and even mental preparation.

AIM

Aim of this study was to test a neurocognitive rehabilitative approach based on proprioceptive exercises and proper motor strategy choices, compared with conventional rehabilitation, assessing baropodometric, gait and clinical changes.

DESIGN

Randomized controlled trial.

SETTING

Ambulatory University Centre.

POPULATION

Fourteen subjects (27.9±5.2 years) underwent to a surgical reconstruction of ACL were divided into the two groups.

METHODS

The subjects were randomly assigned into a group who received a specific neurocognitive and perceptive rehabilitation treatment (TG), and into a control group who received the common physical therapy (CG). The following outcome measures were assessed pre-intervention, one, three and six months later: static and dynamic baropodometry, Visual Analog Scale for pain, Short Form SF-36, Range of Motion, trophism of thigh region, edema, Manual Muscle Test, magneto-resonance imaging assessment.

RESULTS

Lower impairment was observed in TG in respect of CG in terms of load asymmetry during static baropodometry (from 7% to 3% vs. from 10% to 7%, interaction time per treatment: P=0.037), less wide steps during gait (effect size=1.05 vs. 0.38 for CG), swelling (treatment effect: P=0.012). A significantly higher improvement (from 35% to 100%) in terms of SF-36 was recorded only in TG for physical activity (P=0.027). CG showed a quite higher walking speed (treatment effect: P=0.049).

CONCLUSION

Even if further studies are needed on larger samples, the obtained results showed that a neurocognitive rehabilitative approach could be an effective treatment after ACL-reconstruction: in TG we observed a more rapid load symmetrization, the reduction of step width and a more rapid resolution of edema.

CLINICAL REHABILITATION IMPACT

Posture, gait, clinical features and quality of life could benefit from a neurocognitive rehabilitation after ACL surgical reconstruction.

Using magnetic resonance imaging to determine preoperative autograft sizes in anterior cruciate ligament reconstruction

PURPOSE

Accurate prediction of autograft size for anterior cruciate ligament reconstruction can assist in preoperative planning and decision-making regarding graft choices. This study seeks to determine the accuracy of MRI measurements by comparing intraoperative measurements of the patella, semitendinosis, and gracilis tendons while correlating these measurements with patient anthropometric data such as gender, height, and weight.

METHODS

A series of 20 consecutive patients were enrolled who underwent a magnetic resonance imaging study of the knee and proceeded with surgical reconstruction of the anterior cruciate ligament. Intraoperative measurements of the diameter of semitendinosis and gracilis tendons or width of patella tendon were compared to radiographic measurements obtained on the MRI. These measurements were analyzed using a paired t-test as well as regression analysis to evaluate strength of correlation between measurements and also to determine correlation with height, weight, and gender.

RESULTS

There was no statistical difference between intraoperative and radiographic measurements (p > 0.05). There was strong correlation (Pearson r = 0.98, p = 0.00) found between intraoperative and radiographic measurements of the autograft tendons. Weaker correlation was seen with gender, height, and weight with intraoperative measurements.

CONCLUSIONS

Measuring the diameter of the semitendinosis and gracilis tendons and patellar width on MRI can give an accurate prediction of actual intraoperative sizes of these anatomic structures. Height, weight, and gender were also correlated with tendon sizes implying that a patient of female gender or of smaller stature in height or weight may have smaller tendon sizes. Routine use of preoperative MRI measurements can guide surgeons with specific graft preferences to other surgical options if the graft is measured to be insufficient in size.

Knee function after anterior cruciate ligament reconstruction with patellar or hamstring tendon: a meta-analysis

BACKGROUND

There is currently no consensus regarding the best graft type for anterior cruciate ligament reconstruction. Therefore, the aim of this study was to investigate the effects of patellar and hamstring tendon grafts on long-term knee function after anterior cruciate ligament reconstruction.

METHODS

This meta-analysis was conducted according to the methodological guidelines outlined by the Cochrane Collaboration. An electronic search of the literature was performed and all trials published between January 1966 and August 2011 comparing knee function after anterior cruciate ligament reconstruction using patellar tendon grafts with knee function after reconstruction with hamstring tendon grafts were pooled. Six studies were included in the final meta-analysis.

RESULTS

Anterior cruciate ligament reconstruction using hamstring tendon grafts resulted in greater pain upon kneeling than reconstruction using patellar tendon grafts (P = 0.001). However, both grafts resulted in similar levels of anterior tibial translation, and similar results regarding isokinetic extension/flexion tests, Lysholm scores, and the stair-hop test (P > 0.05).

CONCLUSION

Anterior cruciate ligament reconstruction using patellar or hamstring tendon grafts results in similar long-term knee function.

Patellar tendon versus hamstring tendon autograft for anterior cruciate ligament rupture in adults

BACKGROUND

Reconstruction of the anterior cruciate ligament (ACL) commonly involves patellar tendon (PT) or hamstring tendon(s) (HT) autografts. There is no consensus with respect to the choice between these two grafts in ACL surgery.

OBJECTIVES

This review compared the outcomes of ACL reconstruction using PT versus HT autografts in ACL deficient patients.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (April 2008), the Cochrane Central Register of Controlled Trials (2008, Issue 2), MEDLINE (1966 to April 10 2008), EMBASE (1980 to April 10 2008), conference proceedings and reference lists. No language restrictions were applied.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing outcomes (minimum two year follow-up) following ACL reconstruction using either PT or HT autografts in skeletally mature adults, irrespective of the number of bundles, fixation method or incision technique.

DATA COLLECTION AND ANALYSIS

After independent study selection, the four authors independently assessed trial quality and risk of bias, and extracted data using pre-developed forms. Trial authors were contacted for additional data and information. Risk ratios with 95% confidence intervals were calculated for dichotomous outcomes, and mean differences and 95% confidence intervals for continuous outcomes.

MAIN RESULTS

Nineteen trials providing outcome data for 1597 young to middle-aged adults were included. Many trials were at high risk of bias reflecting inadequate methods of randomization, lack of blinding and incomplete assessment of outcome.Pooled data for primary outcomes, reported in a minority of trials, showed no statistically significant differences between the two graft choices for functional assessment (single leg hop test), return to activity, Tegner and Lysholm scores, and subjective measures of outcome. There were also no differences found between the two interventions for re-rupture or International Knee Documentation Committee scores. There were inadequate long-term results, such as to assess the development of osteoarthritis.All tests (instrumental, Lachman, pivot shift) for static stability consistently showed that PT reconstruction resulted in a more statically stable knee compared with HT reconstruction. Conversely, patients experienced more anterior knee problems, especially with kneeling, after PT reconstruction. PT reconstructions resulted in a statistically significant loss of extension range of motion and a trend towards loss of knee extension strength. HT reconstructions demonstrated a trend towards loss of flexion range of motion and a statistically significant loss of knee flexion strength. The clinical importance of the above range of motion losses is unclear.

AUTHORS' CONCLUSIONS

There is insufficient evidence to draw conclusions on differences between the two grafts for long-term functional outcome. While PT reconstructions are more likely to result in statically stable knees, they are also associated with more anterior knee problems.

Dual tunnel medial patellofemoral ligament reconstruction for patients with patellar dislocation using a semitendinosus tendon autograft

The purpose of this study was to describe a safer and more anatomical technique of MPFL reconstruction and to report the short-term results. The subjects included 20 patients with patellar dislocation with a mean age of 23. The operation was performed using a double-looped autogenous semitendinosus tendon graft. Two small bone tunnels were made at the medial edge of the patella, mimicking the wide patellar insertion of the MPFL and a bone tunnel was made at the femoral insertion site. The free ends of the graft attached to the patella and the loop end was fixed to the femoral side. Five patients were available for follow-up interviews by telephone and the remaining 15 were directly examined by physical examination and radiographic evaluation at 2 years or longer postoperatively. The average follow-up period was 30 months. Re-dislocation or patellar fracture was not seen in any patients. The average Kujala's score was 96 with a range from 84 to 100. Six patients were classified as excellent and 14 as good, according to the Crosby and Insall grading system. Radiographically, narrowing of the patellofemoral joint space was observed in 2 cases with previous osteochondral fracture out of those who were directly examined. The dual tunnel MPFL reconstruction produces favorable results in subjective and functional assessment of outcome without complications.

Knee proprioception following ACL reconstruction; a prospective trial comparing hamstrings with bone-patellar tendon-bone autograft

We prospectively studied knee proprioception following ACL reconstruction in 40 patients (34 men and six women; mean age 31 years). The patients were allocated into two equal groups; group A underwent reconstruction using hamstrings autograft, and group B underwent reconstruction using bone-patellar tendon-bone autograft. Proprioception was assessed in flexion and extension by the joint position sense (JPS) at 15°, 45° and 75°, and time threshold to detection of passive motion (TTDPM) at 15° and 45°, preoperatively and at 3, 6 and 12 months postoperatively. The contralateral healthy knee was used as internal control. No statistical difference was found between the ACL-operated and the contralateral knees in JPS 15°, 45° and 75° at 6 and 12 months, in both study groups. No statistical difference was found between the ACL-operated and the contralateral knees in TTDPM 15° at 6 and 12 months, nor regarding TTDPM 45° at 3, 6 and 12 months, in group A. No statistical difference was found in JPS and TTDPM between the two grafts, at any time period. Knee proprioception returned to normal with ACL reconstruction at 6 months postoperatively, without any statistically significant difference between the autografts used.

Does autograft choice determine intermediate-term outcome of ACL reconstruction?

PURPOSE

Many clinical studies and systematic reviews have compared the short-term (2 years) outcomes of ACL reconstruction with hamstring and patellar tendon autograft. Few differences have been observed, with the exception of increased kneeling pain with patellar tendon grafts. The goal of this systematic review is to determine whether there are differences in clinical, patient-reported, or radiographic outcomes based on graft choice at a minimum of 5 years after ACL reconstruction.

METHODS

A systematic review was performed to identify all prospective outcome studies comparing patellar tendon and hamstring autograft ACL reconstruction with minimum follow-up of at least 5 years. Seven studies were identified and meta-analysis of select data determined to be sufficiently homogenous was performed (failure and laxity).

RESULTS

Five randomized controlled trials and two prospective cohorts comparing hamstring and patellar tendon autografts were identified. Clinical assessment [failure rate, International Knee Documentation Committee (IKDC) class, Lachman, pivot shift, and KT 1000 testing] showed no difference between grafts. Patient-reported outcomes (Lysholm, Cincinnati, and IKDC) showed no difference. Both anterior knee pain (3/3 studies) and kneeling pain (4/4 studies) were more frequent in the patellar tendon group. However, the patient-reported outcomes in these studies were not different. Radiographic evidence of osteoarthritis was inconsistent between autograft choices.

CONCLUSION

This level II systematic review demonstrates no difference in major clinical results between graft types with the exception of increased anterior knee and kneeling pain. There exists a potential for increased incidence of osteoarthritis in the patellar tendon group but increased sample size is required. These longer-term outcomes are similar to results of prior systematic reviews with two-year follow-up.

Valgus and flexion deformity after reconstruction of the anterior cruciate ligament in a skeletally immature patient

Anterior cruciate ligament reconstruction in children with open physes is still a topic of debate. We report a unique case of growth disturbance in valgus and flexion of the distal femoral epiphysis, after an ACL reconstruction in a 14.5-year-old boy. The Clocheville technique using the patellar tendon was performed. The femoral tunnel and tibial groove were both positioned above the growth plates. Eighteen months after ACL reconstruction, the patient had to be re-operated on for a valgus and flexion deformity of the femoral epiphysis. The clinical, radiological and aesthetic results were satisfactory. The angular deformity was caused by the fact that either the femoral tunnel was too close to the posterolateral femoral growth plate or an excessive eccentric traction of the graft in relation to the central point of the knee.

Tibial inlay for posterior cruciate ligament reconstruction: a systematic review

Although no consensus has been reached regarding the management of PCL deficiency, in vitro and in vivo studies have investigated whether the tibial inlay technique restores the anatomical site of insertion of the PCL, prevents elongation, stretching, graft failure, and improves long-term PCL stability. A systematic search using PubMed, Ovid, the Cochrane Reviews, and Google Scholar databases using 'posterior cruciate ligament tear', 'Tibial inlay technique' and 'posterior cruciate ligament reconstruction' as keywords identified 71 publications, of which 10 were relevant to the topic, and included a total of 255 patients. The tibial inlay technique restores the anatomic insertion site of the PCL, eliminates the killer turn effect, and places the graft at lower potential risk for abrasion and subsequent rupture. It has the disadvantages of increased operating time and risk to the posterior neurovascular structures. There was no evidence of an association between outcome results and Coleman methodology score, but the Coleman methodology scores correlated positively with the level-of-evidence rating. The methodological quality of the studies included has not improved over the years. Given the few reported published findings, we cannot ascertain whether this procedure may provide a consistent alternative to commonly used PCL surgical strategies. The lack of published randomized clinical trials and few reported findings did not allow to ascertain whether the tibial inlay for posterior cruciate ligament reconstruction may provide a consistent alternative to commonly used PCL surgical strategies and to demonstrate procedure efficacy.