Irradiated Hamstring Tendon Allograft Versus Autograft for Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction: Midterm Clinical Outcomes

What's in a Name? Defining 'Failure' in Anterior Cruciate Ligament Reconstruction Randomized Controlled Trials: A Systematic Review

PURPOSE OF REVIEW

Graft failure, one of the most common outcomes in anterior cruciate ligament reconstruction randomized controlled trials, lacks a consensus definition. The purpose of this study was to systematically summarize current practice and parameters in defining anterior cruciate ligament reconstruction graft 'failure'.

RECENT FINDINGS

Forty studies (4466 participants) satisfied the inclusion criteria. Of these, 90% either defined failure formally or referenced the etiology of failure, the remaining 10% used the term failure without referencing the anterior cruciate ligament reconstruction graft. Among the included studies, there was a high level of inconsistency between the definitions of graft failure. The extracted data was categorized into broader groups, revealing abnormal knee laxity (80%) and graft re-rupture (37.5%) as the most common parameters incorporated in the definitions of graft failure in high-level randomized controlled trials. This review shows that anterior cruciate ligament reconstruction randomized controlled trials lack a consistent definition for graft failure. A universal definition is vital for clarity in medical practice and research, ideally incorporating both objective (e.g. graft re-rupture) and subjective (e.g. validated questionnaires) parameters. A composite outcome should be established which includes some of the common parameters highlighted in this review. In the future, this review can be used to assist orthopaedic surgeons to establish a formal definition of anterior cruciate ligament reconstruction graft 'failure'.

Superior Biological Healing of Hamstring Autografts Compared with Tibialis Allografts after Anterior Cruciate Ligament Reconstruction: A Propensity Score Matching Analysis Based on Second-Look Arthroscopy

Background and Objectives: Remodeling and healing of the graft are crucial processes for long-term graft survival after anterior cruciate ligament reconstruction (ACLR). However, few studies have objectively evaluated the differences in graft healing between autografts and allografts. This study aimed to compare the status of the anterior cruciate ligament (ACL) grafts between hamstring tendon (HT) autografts and tibialis anterior tendon (TAT) allografts using second-look arthroscopy. Materials and Methods: The outcomes of 193 consecutive patients (153 males and 40 females, with an average age of 30.38 and BMI of 25.43 kg/m2) who underwent second-look arthroscopy following primary ACLR were retrospectively reviewed. Prior to participating in this study, all patients provided written informed consent. The patients were divided into two groups: those with HT autografts and those with TAT allografts. Confounding factors were matched between the two groups using propensity score matching (PSM). ACL graft status was assessed during second-look arthroscopy using a numeric scale system based on the degree of four parameters: graft tension, continuity, synovium coverage, and vascular marking. Clinical outcomes were assessed using the Lysholm and International Knee Documentation Committee (IKDC) scores. Graft status and clinical outcomes were compared between the two groups. Additionally, a subgroup analysis based on the timing of the second-look arthroscopy (12-24 months vs. >24 months after the initial ACLR) was conducted. Results: After PSM, 62 patients were included in each group. The second-look arthroscopy was conducted at 23.6 ± 6.6 months for the HT group and at 24.0 ± 7.9 months for the TAT group (p = 0.749). The continuity and tension of the ACL graft were not significantly different between the two groups (p = 0.146 and 0.075, respectively). However, the TAT group exhibited significantly inferior synovial coverage and vascular marking of the ACL graft compared with the HT group (p = 0.021 and 0.007, respectively). These findings were consistent regardless of the timing of the second-look arthroscopy. Clinical outcomes, according to the Lysholm and IKDC scores, significantly improved in both groups with no significant differences (p = 0.386 and 0.733, respectively). Conclusions: Although there were no differences in graft tension and continuity between HT autografts and TAT allografts, the biological healing of ACL grafts, in terms of synovialization and vascularization, was superior in HT autografts compared to TAT allografts.

Incidence of Osteoarthritis Between ACL Reconstruction With Different Graft Types and Between ACL Reconstruction and Repair: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Background

Variation in stiffness, fixation methods, and donor-site morbidity after anterior cruciate ligament reconstruction (ACLR) with different graft types and with anterior cruciate ligament suture repair (ACLSR) can lead to differences in dynamic knee laxity and consequent differences in posttraumatic osteoarthritis (PTOA) development.

Purpose

To compare the incidence of PTOA between different graft types used for primary ACLR and between primary ACLR and ACLSR. It was hypothesized that the incidence of PTOA would vary between ACLR with different autografts and allografts and between ACLR and ACLSR.

Study Design

Systematic review; Level of evidence, 1.

Methods

A search of the literature was performed to identify all randomized controlled trials (RCTs) comparing radiographic evidence of PTOA after ACLR between different graft types-hamstring tendon (HT) autograft, bone-patellar tendon-bone (BPTB) autograft, quadriceps tendon autograft, and allograft-and between ACLR and ACLSR. The minimum follow-up was 2 years. Study quality was assessed using the modified Coleman Methodology Score. A meta-analysis was performed to determine whether there was a difference in the incidence of PTOA between the different graft types and between ACLR and ACLSR.

Results

Eleven randomized controlled trials were included in the meta-analysis-HT: 440 patients (mean follow-up, 9.7 years); BPTB: 307 patients (mean follow-up, 11.8 years); allograft: 246 patients (mean follow-up, 5 years); ACLSR, 22 patients (5 years). No study reporting the incidence after ACLR with quadriceps tendon was included. The study quality ranged from 70 to 88. The meta-analysis indicated no significant difference in the incidence of PTOA between graft types used for ACLR and between ACLR and ACLSR (risk ratios: HT vs BPTB, 1.05; HT vs allograft, 0.81; BPTB vs allograft, 0.82; HT vs ACLSR, not estimable [P > .05 for all]). The combined number of patients with PTOA in all studies per graft type showed that patients who underwent ACLR with a BPTB autograft had the highest percentage of PTOA (HT, 23.4%; BPTB, 29.6%; allograft, 8.1%; ACLSR, 0%). However, excluding studies with a follow-up <5 years resulted in similar outcomes for patients with an HT autograft and a BPTB autograft.

Conclusion

This meta-analysis reported no difference in the incidence of PTOA between graft types used for ACLR and between ACLR and ACLSR. More research is necessary to make a reliable conclusion about which technique is associated with the lowest incidence of PTOA after ACL surgery.

Cross-cultural adaptation and measurement properties of the Persian version of the modified Cincinnati knee rating system

Purpose

To validate and assess the cross-sectional adaptation of the modified Cincinnati knee rating system (MCRKS) Persian translation.

Methods

To assess test-pretest reliability, 102 participants were asked to fill out the MCRKS (Per) scale after anterior cruciate ligament (ACL) reconstruction surgery. Internal consistency (Cronbach's α), reliability (intraclass correlation coefficients), construct validity (Pearson's r) and sensitivity (floor/ceiling effect) were determined. In addition, patients completed other relevant measures as the ACL return to sports after injury (ACL-RSI) survey, hospital for special surgery ACL satisfaction survey (HSS ACL-SS), visual analogue scale (VAS) of pain and patient's satisfaction, Tegner activity score (TAS), single assessment numeric evaluation, and Lysholm score.

Results

Using MCRKS (Per), the internal consistency (Cronbach's α) was 0.9 (if item deleted: 0.81-0.86); the construct validity (Pearson's r) varied between -0.50 (for VAS pain scale) and 0.79 (for Lysholm score); the reliability (ICC value) varied between 0.82 and 0.97; furthermore, no ceiling or floor effect was present.

Conclusion

The MCRKS (Per) has adequate measurement properties and is considered a valid, reliable and sensitive instrument which can identify clinical outcomes after ACLR surgery.

Level of Evidence

Level IV.

Fragile Statistical Findings in Randomized Controlled Trials Evaluating Autograft Versus Allograft Use in Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To analyze the statistical stability of randomized controlled trials (RCTs) evaluating the surgical management of autografts versus allografts in the anterior cruciate ligament reconstruction (ACLR) literature and calculate the fragility index (FI) and fragility quotient and explore a subgroup analysis by calculating the proportion of outcome events where the FI was less than the number of patients lost to follow-up.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a systematic search in the PubMed and Cochrane databases to identify RCTs published between 2000 and 2022 that investigated the use of autografts versus allografts in ACLR literature and reported dichotomous data. The fragility index of each dichotomous variable was calculated through the reversal of a single outcome event until significance was reversed. The fragility quotient was calculated by dividing each fragility index by the study sample size. The interquartile range also was calculated.

RESULTS

Of the 4407 articles screened, 23 met the search criteria, with 11 RCTs evaluating ALCR using autografts and allografts included for analysis. Two hundred and 18 outcome events with 32 significant (P < .05) outcomes and 186 nonsignificant (P ≥ .05) outcomes were identified. The overall fragility index and fragility quotient for all 218 outcomes were 6 subjects (interquartile range 5-8) and 0.058 (interquartile range 0.039-0.077). Fragility analysis of statistically significant outcomes and nonsignificant outcomes had a fragility index of 3.5 (interquartile range 1-5.5) and 6 (interquartile range 5-8), respectively. All of the studies reported a loss to follow-up where 45.5% (5) reported a loss to follow-up greater or equal to 6.

CONCLUSIONS

The RCTs in the ACLR peer-reviewed literature evaluating autograft versus allograft use are vulnerable to a small number of outcome event reversals and exemplify significant statistical fragility in statistically significant findings.

LEVEL OF EVIDENCE

Level I, systematic review of Level I studies.

New Considerations in ACL Surgery: When Is Anatomic Reconstruction Not Enough?

➤ Clinicians should be careful to assess for associated injuries including anterolateral complex and medial meniscal ramp lesions or lateral meniscal posterior root tears.➤ Consideration of lateral extra-articular augmentation should be given for patients with >12° of posterior tibial slope.➤ Patients with preoperative knee hyperextension (>5°) or other nonmodifiable risk factors, including high-risk osseous geometry, may benefit from a concomitant anterolateral augmentation procedure to improve rotational stability.➤ Meniscal lesions should be addressed at the time of anterior cruciate ligament reconstruction with meniscal root or ramp repair.

Current trends in graft choice for primary anterior cruciate ligament reconstruction - part II: In-vivo kinematics, patient reported outcomes, re-rupture rates, strength recovery, return to sports and complications

Postoperative patient satisfaction after anterior cruciate ligament reconstruction (ACL-R) is influenced mainly by the degree of pain, the need for reoperation, and functional performance in daily activities and sports. Graft choice has shown to have an influence on postoperative outcomes after ACL-R. While patient reported outcomes measurements do not differ between graft options, evidence shows that normal knee kinematics is not fully restored after ACL-R with an increase in postoperative anterior tibial translation (ATT). Postoperative graft rupture rates seem to favor bone-patella-tendon-bone (BPTB) and quadriceps tendon (QT) autografts over HT or allografts. While return to sports rates seem comparable between different graft types, postoperative extensor strength is reduced in patients with BPTB and QT whereas flexion strength is weakened in patients with HT. Postoperative donor site morbidity is highest in BPTB but comparable between HT and QT. With all graft options having advantages and drawbacks, graft choice must be individualized and chosen in accordance with the patient.

Minimally Invasive Knee Lateral Collateral Ligament Reconstruction Using Partial Biceps Femoris Tendon Autograft

Lateral collateral ligament (LCL) is known as an important ligament to restrain varus force of the knee, especially in 30° knee flexion. From the anatomical study, the insertion of LCL at proximal fibula is intimately close to the insertion of biceps femoris (BF) tendon. Since LCL is infrequently injured in isolation, and with limitation in availability of autograft and allograft, this study proposes the partial anterior BF tendon as an alternative autograft source to reconstruct the LCL. This could be performed either by minimally invasive procedure or standard open technique. The core concept is to preserve the posterior part of the BF tendon to protect the peroneal nerve, by which exploration of this nerve and the proximal fibula prior to LCL reconstruction could be exempted. Minimally invasive LCL reconstruction using this autograft would essentially reduce soft tissue injury, shorten the operative time, and enhance recovery of the reconstructed knee.

High Levels of Satisfaction and Adequate Patient-Reported Outcomes After Operative Reconstruction of Multiligament Knee Injury With Allograft Among Patients Aged 40 Years and Older

Purpose

To describe injury characteristics and patient-reported outcomes (PROs) among patients aged 40 years and older who underwent allograft reconstruction for multiligament knee injury (MLKI).

Methods

Records of patients aged 40 years and older who underwent allograft multiligament knee reconstruction at a single institution between 2007 and 2017 with a minimum of 2 years of follow-up were retrospectively reviewed. Demographic information, concomitant injuries, patient satisfaction, and PROs including International Knee Documentation Committee and Marx activity scores were obtained.

Results

Twelve patients were included with a minimum follow-up time of 2.3 years (mean, 6.1; range, 2.3-10.1 years) and a mean age at surgery of 49.8 years. Seven patients were male, and the most common mechanism of injury was sport-related. The most frequently reconstructed MLKIs were anterior cruciate ligament and medial collateral ligament (4), anterior cruciate ligament and posterolateral corner (2), and posterior cruciate ligament and posterolateral corner (2). The majority of patients reported satisfaction with their treatment (11). Median International Knee Documentation Committee and Marx scores were 73 (interquartile range, 45.5-88.0) and 3 (interquartile range 0-5), respectively.

Conclusions

Patients aged 40 years and older can expect a high level of satisfaction and adequate PROs at 2-years follow-up after operative reconstruction for a MLKI with allograft. This demonstrates that allograft reconstruction for a MLKI in older patients may have clinical utility.

Level of Evidence

IV, therapeutic case series.

Characteristics of return to running programs following an anterior cruciate ligament reconstruction: A scoping review of 64 studies with clinical perspectives

OBJECTIVE

To (1) describe return to running (RTR) programs used during rehabilitation after anterior cruciate ligament reconstruction (ACLR); and (2) provide clinical guidelines for RTR program after ACLR.

DESIGN

Scoping review.

LITERATURE SEARCH

We searched the MEDLINE (Pubmed), EMBASE, Web of Science and PEDro databases.

STUDY SELECTION CRITERIA

We included randomized controlled trial (RCT), cases series, meta-analyses, both scoping and systematic reviews including a rehabilitation program after ACLR with a specific RTR program. A "Running program checklist" (RPC) was elaborated based on the Template for Intervention Description and Replication (TIDieR), and on the Consensus on Exercise Reporting Template (CERT) checklist.

DATA SYNTHESIS

The percentage and number of studies specifying each of the running program checklist items in their RTR program were reported. Number of items reported in each study and specific analysis item-by-item were also proposed.

RESULTS

The "When (2)" item was the most frequently found (92.19%) and, conversely, the "Who (1)" item appeared only in four studies (6.2%). One-third of the studies presented only one item of the RPC, and 48 of the 64 articles discussed less than three items. Two studies described in detail their RTR program by reporting 8 and 9 items out of the 10, respectively. No study presented 10 of the PRC items.

CONCLUSION

There is a serious lack of information concerning RTR program following ACLR in the literature and further studies are needed to establish a program based on the best evidence.

Autograft and Nonirradiated Allograft for Anterior Cruciate Ligament Reconstruction Demonstrate Similar Clinical Outcomes and Graft Failure Rates: An Updated Systematic Review

Purpose

To perform an updated systematic review comparing the clinical outcomes of autograft versus nonirradiated allograft for anterior cruciate ligament reconstruction (ACLR).

Methods

A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines by searching PubMed, the Cochrane Library, and Embase to identify comparative studies directly comparing outcomes of primary ACLR with autograft versus nonirradiated allograft with a minimum 2-year follow-up. The search terms used were: “anterior cruciate ligament” AND autograft AND allograft AND (irradiation OR non-irradiated). Patients were evaluated based on graft failure rates, the Objective International Knee Documentation Committee (IKDC) score, anteroposterior laxity, and patient-reported outcomes (Subjective IKDC score, the visual analog scale [VAS], the Cincinnati Knee Rating System, Lysholm, and Tegner scores). Risk of bias was assessed using the ROBINS-I and Cochrane Collaboration’s risk of bias tool for non-randomized and randomized studies, respectively.

Results

Sixteen studies (3 Level I, 7 Level II, 6 Level III) met inclusion criteria, including a total of 15,502 patients undergoing ACLR with autograft and 1,577 with nonirradiated allograft. The average follow-up ranged from 24.0 to 132.0 months. Graft failure ranged from 0% to 9.4% of patients in the autograft group and 0% to 26.5% in the allograft group. Two studies showed greater failure rates among younger patients in the allograft group. There were no significant differences between the Objective IKDC score, anteroposterior laxity, or patient-reported outcomes between the groups within any of the included studies (P > .05).

Conclusions

Autograft and nonirradiated allograft for primary ACLR demonstrate similar patient-reported outcomes and graft failure rates.

Level of Evidence

III, systematic review of level I-III studies.

Current trends in the anterior cruciate ligament part II: evaluation, surgical technique, prevention, and rehabilitation

Clinical evaluation and management of anterior cruciate ligament (ACL) injury is one of the most widely researched topics in orthopedic sports medicine, giving providers ample data on which to base their practices. The ACL is also the most commonly treated knee ligament. This study reports on current topics and research in clinical management of ACL injury, starting with evaluation, operative versus nonoperative management, and considerations in unique populations. Discussion of graft selection and associated procedures follows. Areas of uncertainty, rehabilitation, and prevention are the final topics before a reflection on the current state of ACL research and clinical management of ACL injury. Level of evidence V.

Hamstrings substitution via anteromedial portal with optional anterolateral ligament reconstruction is the preferred surgical technique for anterior cruciate ligament reconstruction: a survey among ESSKA members

PURPOSE

The objective of this study was to report on a worldwide web-based survey among the ESSKA community developed to investigate current recommendations regarding ACL reconstruction surgical procedures.

METHODS

All contacts in the official mailing list of the ESSKA were contacted to investigate preferences regarding graft type, anterolateral ligament reconstruction, femoral tunnel drilling technique, single-bundle vs double-bundle technique, femoral and tibial fixation methods.

RESULTS

Eight-hundred and twenty responses were analyzed. Hamstrings autograft was the graft of choice in male patients for 634 (79%) and in female patients for 674 (84%) responders, while its preference for ACL reconstruction in professional athletes was for 401 (50%). 480 (63%) surgeons surveyed would include anterolateral ligament reconstruction only if diagnosed and remaining instability after ACL surgery or revision. 598 (75%) respondents were in favor of anteromedial portal for femoral tunnel drilling. The most popular femoral fixation technique was found to be cortical suspension (500-66%), while a compression system was preferred on the tibial side by 537 (71% of the sample).

CONCLUSIONS

This survey study found that HT autograft, single-bundle reconstruction, anteromedial portal for femoral tunnel drilling, cortical suspension systems for femoral fixation and compression systems for tibial fixation represent the current standard of ACLR in a large community of orthopedic surgeons. The present study performed with surgeons who are members of the ESSKA community will help to comprehend the actual ACLR worldwide practice patterns. Due to low response rate, these results should be interpreted with caution and not to be intended to represent the state of the art of ESSKA community.

LEVEL OF EVIDENCE

III.

A Systematic Review of Risk Factors for Anterior Cruciate Ligament Reconstruction Failure

Although most studies have introduced risk factors related to anterior cruciate ligament reconstruction failure, studies on combinations of high-risk factors are rare. To provide a systematic review of the risk factors of anterior cruciate ligament reconstruction failure to guide surgeons through the decision-making process, an extensive literature search was performed of the Medline, Embase and Cochrane Library databases. Studies published between January 1, 2009, and September 19, 2019, regarding the existing evidence for risk factors of anterior cruciate ligament reconstruction failure or graft failure were included in this review. Study quality was evaluated with the quality index. Ultimately, 66 articles met our criteria. There were 46 cases classified as technical factors, 21 cases as patient-related risk factors, and 14 cases as status of the knee joint. Quality assessment scores ranged from 14 to 24. This systematic review provides a comprehensive summary of the risk factors for anterior cruciate ligament reconstruction failure, including technical factors, patient-related factors, and the factors associated with the status of the knee joint. Emphasis should be placed on avoiding these high-risk combinations or correcting modifiable risk factors during preoperative planning to reduce the rate of graft rupture and anterior cruciate ligament reconstruction failure.

The long-term outcomes of different grafts in anterior cruciate ligament reconstruction: a network meta-analysis

OBJECTIVES

To compare the long-term prognosis of patients with different types of grafts used in anterior cruciate ligament reconstruction (ACLR).

METHODS

PubMed, Ovid (MEDLINE and Embase) and the Cochrane library were searched up to Feb 2020. Eligible studies about different grafts in ACLR were searched for identifying the evidence comparing the long-term (mean or median follow-up time or the general description of the follow-up time≥2 years) knee outcomes of different grafts for ACLR. The final included articles and evaluation criteria were confirmed by the authors and senior clinicians to ensure the validity of the included articles. Lysholm score, the results of pivot shift test, Lachman test and International Knee Documentation Committee (IKDC) evaluation were selected as prognostic indicators. A Bayesian network meta-analysis was conducted.

RESULTS

A total of 30 articles were included in our network meta-analysis. Finally, we found that artificial graft or augmentation can provide the not bad Lysholm score but the worse result of IKDC evaluation for patients with ACLR compared with other types of grafts. Double-bundle hamstring autograft can provide a good Lysholm score as well as lower positive rate of pivot shift test and Lachman test. Patellar tendon autograft can provide the better result of IKDC evaluation. The patients with allogeneic tendon graft may get the higher positive rate of pivot shift test and Lachman test. Patients with single-bundle hamstring autograft may get the ordinary result of IKDC evaluation and Lysholm score.

CONCLUSIONS

Double-bundle hamstring autograft may be a better choice because of more items of good prognosis for the patients with ACLR. Patellar tendon autograft is a right choice which only shows the disadvantage on the Lysholm score. The prognosis of patients with single-bundle hamstring autograft is ordinary. The effect of artificial graft or augmentation needs more evidence to prove. Allogeneic tendon graft is not a better choice when compared with other grafts referred in our network meta-analysis.

TRANSLATIONAL POTENTIAL STATEMENT

In this study, we made a comprehensive comparison of the grafts commonly used in anterior cruciate ligament reconstruction. The evidence presented in this study provides a reference for clinicians to select a suitable anterior cruciate ligament graft.

Allograft for Anterior Cruciate Ligament Reconstruction (ACLR): A Systematic Review and Meta-Analysis of Long-Term Comparative Effectiveness and Safety. Results of a Health Technology Assessment

Purpose

To evaluate whether allograft anterior cruciate ligament reconstruction (ACLR) is superior or inferior to autograft ACLR or conservative management in terms of effectiveness and safety.

Methods

A systematic review of the evidence for allograft ACLR was conducted. Randomized controlled trials with a minimum mean follow-up time of 5 years were included. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and the EUnetHTA-Core-Model were used as reporting standards. A meta-analysis was conducted for selected crucial outcomes using a random-effects model. The strength of the available evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation approach.

Results

Six randomized trials were included comparing allograft with autograft. Patients were on average between 28 and 32.8 years of age (allograft group) and 28.9 and 31.7 years of age (autograft group). Based on the crucial outcomes, the meta-analyses showed no statistically significant differences in Lysholm score, Tegner score, and Cincinnati Knee Score between groups. A small statistical difference favoring autografts was found across studies in the subjective International Knee Documentation Committee score (–2.25; 95% confidence interval –3.02 to –1.47; I² = 0%; range of all scores: 73.7-90). Two of six studies reported on graft failure, with a statistically significant difference to the detriment of using allografts (13/49 [26.5%] vs 4/48 [8.3%] in one study, 13/43 [30.2%] vs 3/40 [7.5%] in the other study).

Conclusions

Although no substantial difference in patient-reported function, activity level, and symptoms was demonstrated, evidence from the included studies showed a greater risk for graft failure or revision that may make allograft a less safe treatment modality in ACLR. The strength of available evidence is low based on the crucial outcomes due to the lack of high-quality research and the present increased risk of bias in primary studies. Priority should be shifted toward reflecting on whether there is a subpopulation for whom allograft ACLR may still be advantageous in theory (e.g., less-active older patients) and further conduct RCTs in this population.

Level of Evidence

Level II, systematic review of Level II evidence studies.

Comparative Efficacy of Graft Options in Anterior Cruciate Ligament Reconstruction: A Systematic Review and Network Meta-Analysis

Purpose

To evaluate the effectiveness of various graft options for anterior cruciate ligament reconstruction using network meta-analysis.

Methods

A medical literature search was conducted of PubMed, the Cochrane Library, Embase, SCOPUS, and Web of Science from their inception through March 1, 2019. The outcomes, including International Knee Documentation Committee (IKDC) form, Lachman test, Lysholm score, Pivot shift test, and Tegner score, were evaluated among graft options. Data extraction was carried out according to inclusion and exclusion criteria, and a network meta-analysis was performed using STATA 14.0.

Results

A total of 45 trials with 3992 patients were included. The forest plots revealed no significant differences in IKDC, Lysholm, or Tegner score among the grafts. In Lachman score, a significant difference was found in the comparisons of hamstring tendon allograft (HT-AL) versus patellar tendon autograft (PT-AU) and HT-AL versus hamstring tendon autograft (HT-AU). In pivot shift test, PT-AU was superior to all the other grafts, and quadriceps tendon autograft (QT-AU) was superior to HT-AL and artificial ligament (Art-L) in the number of cases with negative results. According to surface under the cumulative ranking area (SUCRA), PT-AU had the highest probability to be the best intervention in Lachman test and Tegner score; tibialis anterior tendon allograft (TA-AL) in IKDC and Lysholm score; and QT-AU in pivot shift test. Based on the cluster analysis of SUCRA, PT-AU was considered the most appropriate intervention by IKDC and Lachman test.

Conclusion

This study suggests that PT-AU may be the most appropriate graft for ACL reconstruction according to IKDC and Lachman test results.

Level of Evidence

Level I, network meta-analysis of randomized controlled trials.

Failure Rates of Autograft and Allograft ACL Reconstruction in Patients 19 Years of Age and Younger: A Systematic Review and Meta-Analysis

BACKGROUND

Graft choice for pediatric anterior cruciate ligament reconstruction (ACLR) is determined by several factors. There is limited information on the use and outcomes of allograft ACLR in pediatric patients. The purpose of this systematic review and meta-analysis was to quantify reported failure rates of allograft versus autograft ACLR in patients ≤19 years of age with ≥2 years of follow-up. We hypothesized that there would be higher rates of failure for allograft compared with autograft ACLR in this population.

METHODS

PubMed/MEDLINE and Embase databases were systematically searched for literature regarding allograft and autograft ACLR in pediatric/adolescent patients. Articles were included if they described a cohort of patients with average age of ≤19 years, had a minimum of 2 years of follow-up, described graft failure as an outcome, and had a Level of Evidence grade of I to III. Qualitative review and quantitative meta-analysis were performed to compare graft failure rates. A random-effects model was created to compare failure events in patients receiving allograft versus autograft in a pairwise fashion. Data analysis was completed using RevMan 5.3 software (The Cochrane Collaboration).

RESULTS

The database search identified 1,604 studies; 203 full-text articles were assessed for eligibility. Fourteen studies met the inclusion criteria for qualitative review; 5 studies were included for quantitative meta-analysis. Bone-patellar tendon-bone (BTB) represented 58.2% (n = 1,012) of the autografts, and hamstring grafts represented 41.8% (n = 727). Hybrid allografts (autograft + supplemental allograft) represented 12.8% (n = 18) of all allograft ACLRs (n = 141). The unweighted, pooled failure rate for each graft type was 8.5% for BTB, 16.6% for hamstring, and 25.5% for allograft. Allografts were significantly more likely than autografts to result in graft failure (odds ratio, 3.87; 95% confidence interval, 2.24 to 6.69).

CONCLUSIONS

Allograft ACLR in pediatric and adolescent patients should be used judiciously, as existing studies revealed a significantly higher failure rate for allograft compared with autograft ACLR in this patient population. Additional studies are needed to improve the understanding of variables associated with the high ACLR failure rate among pediatric and adolescent patients.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Clinical outcomes and second-look arthroscopic findings of anterior cruciate ligament reconstruction with autograft, hybrid graft, and allograft

Background

There is no consensus as to the choice of grafts for primary anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to compare the clinical and second-look arthroscopic outcomes after ACL reconstruction by use of autograft, hybrid graft, and γ-irradiated allograft.

Methods

Ninety-seven patients who underwent second-look arthroscopy after ACL reconstruction with autografts (28 patients, hamstring autograft), hybrid grafts (32 patients, hamstring autograft augmented with γ-irradiated tibialis anterior tendon allograft), or γ-irradiated allografts (37 patients, tibialis anterior tendons) were included in this study. The clinical outcomes were compared by using Lysholm score, International Knee Documentation Committee (IKDC) score, and Tegner activity score, and the side-to-side differences of KT-1000 measurement. Second-look arthroscopic findings were compared in terms of synovial coverage and graft tension.

Results

There were no statistical significances among the three groups in Lysholm score, IKDC score, or Tegner activity score (P > 0.05). The KT-1000 examination showed more anterior laxity in the γ-irradiated allograft group than in the autograft or hybrid graft groups (P = 0.006, and P = 0.013, respectively). Two patients in the autograft group, 2 patients in the hybrid graft group and 4 patients in the allograft group were evaluated as graft failure on second-look arthroscopy. The synovial coverage was superior in the autograft group than that in the hybrid graft group or the allograft group (P = 0.013 and P = 0.010, respectively), and was comparable between the hybrid graft group and allograft group (P = 0.876). With regard to graft tension, the autograft group and hybrid group were comparable (P = 0.883) but showed better results than the allograft group (P = 0.011 and P = 0.007, respectively).

Conclusion

The hamstring autografts and hybrid grafts used for ACL reconstruction produced equal efficacy but provided better knee stability than allografts. In addition, the hamstring autografts showed better synovial coverage than the other two graft types.

The use of allograft tendons in primary ACL reconstruction

PURPOSE

Graft choice in primary anterior cruciate ligament (ACL) reconstruction remains controversial. The use of allograft has risen exponentially in recent years with the attraction of absent donor site morbidity, reduced surgical time and reliable graft size. However, the published evidence examining their clinical effectiveness over autograft tendons has been unclear. The aim of this paper is to provide a current review of the clinical evidence available to help guide surgeons through the decision-making process for the use of allografts in primary ACL reconstruction.

METHODS

The literature in relation to allograft healing, storage, sterilisation, differences in surgical technique and rehabilitation have been reviewed in addition to recent comparative studies and all clinical systematic reviews and meta-analyses.

RESULTS

Early reviews have indicated a higher risk of failure with allografts due to association with irradiation for sterilisation and where rehabilitation programs and post-operative loading may ignore the slower incorporation of allografts. More recent analysis indicates a similar low failure rate for allograft and autograft methods of reconstruction when using non-irradiated allografts that have not undergone chemically processing and where rehabilitation has been slower. However, inferior outcomes with allografts have been reported in young (< 25 years) highly active patients, and also when irradiated or chemically processed grafts are used.

CONCLUSION

When considering use of allografts in primary ACL reconstruction, use of irradiation, chemical processing and rehabilitation programs suited to autograft are important negative factors. Allografts, when used for primary ACL reconstruction, should be fresh frozen and non-irradiated. Quantification of the risk of use of allograft in the young requires further evaluation.

LEVELS OF EVIDENCE

III.

The gracilis tendon autograft is a safe choice for orthopedic reconstructive procedures: a consecutive case series studying the effects of tendon harvesting

Background

The gracilis tendon is commonly used as an autograft to reconstruct torn tendons or ligaments in many parts of the body. Little is known about the subjective and functional outcome after gracilis tendon harvest. The aim of this study was to evaluate the outcome of the donor leg in patients undergoing such surgery.

Methods

Patients with chronic acromioclavicular joint dislocations undergoing coracoclavicular ligament reconstructions using autogenous gracilis tendon grafts were eligible for this study. The graft harvesting procedure was carried out in a standard fashion using a tendon stripper. Knee injury and Osteoarthritis Outcome Score (KOOS) were collected preoperatively and after 12 months. The first 5 patients were included retrospectively and lacked preoperative data, for these patients age- and gender matched normative KOOS scores were used as baseline values. Isometric knee flexor strength in 60° and 90° degrees of flexion was measured at final follow up at a median of 26 (14–56) months postoperatively with the non-operated leg used as reference.

Results

Twenty four patients were eligible for the study and 2 were excluded. The 22 patients available for analysis had a mean age of 44 (22–62) years at the time of surgery and 4 were women. There was no statistically significant change in KOOS 12 months postoperatively compared to baseline values but the patients were weaker in knee flexion in the operated leg compared to the non-operated one.

Conclusions

Gracilis tendon harvesting results in a weakness of knee flexion but does not impair subjective knee function and is a procedure that can be recommended when an autogenous tendon graft is needed.

Autograft or Allograft? Irradiated or Not? A Contrast Between Autograft and Allograft in Anterior Cruciate Ligament Reconstruction: A Meta-analysis

PURPOSE

To compare the clinical outcomes and adverse events associated with irradiated and nonirradiated allografts in anterior cruciate ligament (ACL) reconstruction.

METHODS

PubMed, Web of Science, and EMBASE were searched for randomized controlled trials from January 1990 to March 2018 to compare autograft with allograft in ACL reconstruction. Both objective and subjective outcomes of the function and adverse events were meta-analyzed. Two comparisons were summarized: (1) autograft and nonirradiated allograft and (2) autograft and irradiated allograft. The bias risk was based on the Cochrane Handbook for Systematic Reviews of Interventions. The overall risk ratio or weighted mean difference was calculated using a fixed- or random-effects model. Heterogeneity between studies was evaluated by the Q and the I² statistics.

RESULTS

Eleven trials were included in this review for meta-analysis. A total of 1,172 patients were involved (465 autograft and 461 nonirradiated allograft; 141 autograft and 138 irradiated allograft patients). The average follow-up varied from 2 to >10 years. The mean patient age varied from 22 to 32.8 years. The total failure rate was 2.5%. Our analyses demonstrated better clinical outcomes in autograft than irradiated allograft, which could be observed clearly through the International Knee Documentation Committee score (3.84; 95% confidence interval [CI], 1.93-5.76; P < .0001; I² = 0%), Lysholm score (2.94; 95% CI, 0.66-5.22; P = .01; I² = 0%), and Tegner score (0.14; 95% CI, -0.08 to 0.36; P = .22; I² = 0%) with fewer adverse events 0.20 (95% CI, 0.11-0.39; P < .00001; I² = 0%). There were no significant differences in autograft and nonirradiated allograft groups (P = .47, P = .27, P = .24, and P = .24, respectively).

CONCLUSIONS

Autograft offered greater advantages in functional outcomes and adverse events than irradiated allograft in ACL reconstruction; however, there were no significant differences between autograft and nonirradiated allograft in ACL reconstruction.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and Level II studies.

Passive anterior tibia translation in anterior cruciate ligament-injured, anterior cruciate ligament-reconstructed and healthy knees: a systematic review

Abstract

Anterior tibia translation (ATT) is mainly prevented by the anterior cruciate ligament. Passive ATT tests are commonly used to diagnose an anterior cruciate ligament (ACL) injury, to select patients for an ACL reconstruction (ACLR), and as an outcome measure after an ACLR. The aim of this review was to present an overview of possible factors determining ATT. A second purpose was to give a summary of the ATT measured in the literature in healthy, ACL-injured and ACLR knees and a comparison between those groups. A literature search was conducted with PubMed. Inclusion criteria were full-text primary studies published in English between January 2006 and October 2016. Studies included reported ATT in explicit data in healthy as well as ACL-injured or ACLR knees or in ACL-injured as well as ACLR knees. Sixty-one articles met inclusion criteria. Two articles measured the ATT in healthy as well as ACL-injured knees, 51 in ACL-injured as well as in ACLR knees, three in ACLR as well as in healthy knees and three in healthy, ACL-injured and ACLR knees. A difference in ATT is found between healthy, contralateral, ACLR and ACL-injured knees and between chronic and acute ACL injury. Graft choices and intra-articular injuries are factors which could affect the ATT. The mean ATT was lowest to highest in ACLR knees using a bone–patella tendon–bone autograft, ACLR knees using a hamstring autograft, contralateral healthy knees, healthy knees, ACLR knees with an allograft and ACL-injured knees. Factors which could affect the ATT are graft choice, ACL injury or reconstruction, intra-articular injuries and whether an ACL injury is chronic or acute. Comparison of ATT between studies should be taken with caution as a high number of different measurement methods are used. To be able to compare studies, more consistency in measuring devices used should be introduced to measuring ATT. The clinical relevance is that an autograft ACLR might give better results than an allograft ACLR as knee laxity is greater when using an allograft tendon.

Level of evidence

III.

Double-bundle anterior cruciate ligament reconstruction is better than single-bundle reconstruction in terms of objective assessment but not in terms of subjective score

PURPOSE

A comparison of clinical outcomes between double-bundle (DB) and single-bundle (SB) anterior cruciate ligament (ACL) reconstruction for patients with ACL injury.

METHODS

Sixty patients were treated with either SB (n = 30) or DB (n = 30) ACL reconstruction between 2011 and 2012. The hamstring tendons were autografted with suspensory fixation on the femoral side, while a bio-absorbable interference screw was used for fixation on the tibial side. These patients were evaluated using Lysholm score, International Knee Documentation Committee (IKDC) forms (both objective and subjective), Lachman test, pivot shift test, and KT 1000 arthrometer.

RESULTS

After a median follow-up duration of 35.5 months (ranging between 30 and 42 months), the frequency of patients who had high objective IKDC scores was significantly higher in the DB group than those in the SB group. In terms of DB, the Lachman test was normal in 26 patients (86.7%), nearly normal in three patients (10%), and abnormal in one patient (3.3%); comparatively, in terms of SB, the Lachman test was normal in 20 patients (66.7%), nearly normal in eight patients (26.7%) and abnormal in two patients (6.6%). The pivot shift test was negative in 29 patients (96.7%) and 21 patients (70%) for DB and SB, respectively. The average KT-1000 side-to-side difference was 1.0 mm for DB and 1.5 mm for SB. The subjective IKDC and Lysholm score showed non-significant differences between both techniques.

CONCLUSION

Double-bundle ACL reconstruction was found to have a significant advantage in anterior and rotational stability as well as objective IKDC than that of SB reconstruction. However, subjective measurements showed no statistical differences between the techniques.

LEVEL OF EVIDENCE

II.

Comparison of clinical outcomes after anterior cruciate ligament reconstruction with hamstring tendon autograft versus soft-tissue allograft: A meta-analysis of randomised controlled trials

BACKGROUND

Hamstring tendon autografts and soft-tissue allograft are commonly used for anterior cruciate ligament (ACL) reconstruction. However, the clinical outcomes between these two grafts are controversial. This meta-analysis was performed to compare clinical outcomes of primary ACL reconstruction with hamstring tendon autografts versus soft-tissue allografts.

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Library were searched through 8 September 2017 to identify randomized controlled studies that compared hamstring tendon autografts with soft-tissue allografts for primary ACL reconstruction. Two authors independently graded the methodological quality of each eligible study using the Cochrane Collaboration tool and extracted relevant data. Statistical heterogeneity among the trials was evaluated with chi-square and I-square tests. A sensitivity analysis was conducted to explore sources of heterogeneity. Subgroup analysis was performed to identify potential differences according to type of reconstruction technique (single-bundle or double-bundle).

RESULTS

Eight studies with 785 combined patients (396 hamstring tendon autografts and 389 soft-tissue allografts) were included. Two studies had a high risk of bias. The other six studies had unclear risk of bias. There were significant differences between the groups in subjective International Knee Documentation Committee (IKDC) score (mean difference [MD], 2.43; 95%CI, 0.69-4.18; p = 0.006), Tegner score (MD, 0.24; 95%CI, 0.03-0.45; p = 0.03), and side-to-side difference (MD, -1.37; 95%CI, -2.44 to -0.30; p = 0.01). There was no significant difference between the groups in Lysholm score, complications, pivot shift test, anterior drawer test, Lachman test, overall IKDC score, or range of motion. Subgroup analysis demonstrated that for primary ACL reconstruction using the single-bundle technique, soft-tissue allografts were inferior to hamstring tendon autografts in subjective IKDC score, anterior drawer test, and side-to-side difference.

CONCLUSION

Soft-tissue allografts are inferior to hamstring tendon autografts with respect to subjective patient evaluation and knee stability but superior in the complication of hypoesthesia for patients undergoing primary ACL reconstruction.

Effects of graft preconditioning on γ-irradiated deep frozen tendon allografts used in anterior cruciate ligament reconstruction

Preconditioning of the grafts prior to implantation into the knee is considered to reduce the loss of tension caused by graft viscoelasticity after anterior cruciate ligament reconstruction. The present study analyzed the impacts of different preconditioning forces on the biomechanical properties of the γ-irradiated deep frozen tendon allografts. A total of 36 tendon grafts were randomly divided into three groups and were preconditioned at 80 N (group 1), 160 N (group 2) and 320 N (group 3) for 10 min. Subsequently, the grafts were gradually completely relaxed for 1 min and subsequently received 25 cyclic loads of 0–80 N. Afterwards, the grafts were loaded to 80 N, which was maintained for 30 min. Finally, load was gradually increased until ultimate failure at maximum load (UFML) was obtained. There were significant differences in the stiffness and UFML values between the 3 groups (all P<0.05). The graft stiffness in group 3 significantly increased compared with the other 2 groups, and the stiffness of group 2 grafts increased compared with group 1. The UFML in group 3 was significantly lower compared with groups 1 and 2, while there was no significant difference between groups 1 and 2. In the present study, the results suggested that increasing the initial tension could effectively reduce the loss of stiffness due to viscoelasticity for the γ-irradiated deep frozen allogeneic tendon grafts. However, overloaded initial tension decreased the tensile strength.

Adolescent Medial Patellofemoral Ligament Reconstruction: A Comparison of the Use of Autograft Versus Allograft Hamstring

Background

Recurrent patellar instability is commonly treated with medial patellofemoral ligament reconstruction (MPFLR), and the use of allograft in anterior cruciate ligament reconstructions has demonstrated inferior outcomes.

Purpose

To compare the outcomes of allografts versus autografts in adolescent MPFLR for patellar instability.

Study Design

Cohort study; Level of evidence, 3.

Methods

A retrospective chart review was completed on patients younger than 18 years who underwent MPFLR for recurrent instability after failed nonoperative management over an 8-year period with a minimum 2-year follow-up. Patients were divided into autograft or allograft hamstring cohorts for comparison. Primary outcome measures were return to normal activity, incidence of redislocation/subluxation, pain, stiffness, other complications, and Kujala scores. Statistical analysis using unpaired t tests was performed, with an alpha value set at P < .05.

Results

After criteria were applied, 59 adolescents (36 allograft, 23 autograft; 38 girls, 21 boys) with a mean ± SD age of 15.2 ± 1.7 years and a mean follow-up of 4.1 ± 1.9 years (allograft, 3.3 ± 1.1 years; autograft, 5.7 ± 2.1 years; P ≤ .001) were included. Seven patients had concurrent osteotomies (3 allograft, 4 autograft), 11 patients had concurrent loose body removals (5 allograft, 6 autograft), and 9 patients had concurrent lateral release (7 allograft, 2 autograft). Between groups, no significant difference was found in change between preoperative and most recent follow-up (mean, 1.2 ± 2.1) or rate of return to sports (mean, 73.3%). In total, 9 surgeries failed (3 allograft, 6 autograft). For the surviving grafts, a statistical difference in mean Kujala scores at final follow-up was noted (allograft, 92.7; autograft, 97.4; P = .02).

Conclusion

We identified no significant differences in return to activity, pain score changes, and incidences of failure between patients undergoing MPFLR with allograft versus autograft. Although teenagers with surviving autograft MPFLR reported statistically higher Kujala scores, the mean score difference of 5 points was not clinically significant. It appears that using allograft tendon instead of autograft tissue for MPFLR in this teenage population does not adversely affect long-term outcomes.

Tibial tunnel enlargement and joint instability after anterior cruciate ligament reconstruction. A prospective comparison between autograft and allograft

PURPOSE

To investigate tibial tunnel widening and knee instability after ACL reconstruction with hamstring autograft or irradiated soft tissue allograft.

METHODS

Eight-two patients were divided into two groups: autograft group and allograft group. Radiographic and clinical evaluations were performed.

RESULTS

Seventy patients were followed up with median of 36.3 months (range 36-38 months). Tibial tunnel widening was at or greater than 30% for nine patients in the autograft group and 15 patients in the allograft group (P = 0.0417). The average percentage of tibial tunnel widening was 26.7 ± 4.0 % and 29.7 ± 5.3 % in autograft and allograft groups, respectively (P = 0.0090). Knee range of motion was not affected by the reconstruction operation or different grafts. Thigh atrophy improved significantly within 24 months after ACL reconstructions in both groups. ACL reconstruction with the allograft leaded to less knee stability than that with the autograft from one year after operation (P = 0.0023). There was no significant difference between two groups with respect to Lysholm score (P = 0.1925) and Tegner score (P =0 .0918) at the final follow-up.

CONCLUSION

The allograft group reported significantly more tibial tunnel widening and knee instability compared with the autograft group.

The potential of using semitendinosus tendon as autograft in rabbit meniscus reconstruction

Since transplantation of meniscal allograft or artificial menisci is limited by graft sources and a series of adverse events, substitution for meniscus reconstruction still needs to be explored. Natural biomaterials, which can provide a unique 3-D microenvironment, remain a promising alternative for tissue engineering. Among them, autograft is a preferred option for its safety and excellent biocompatibility. In this study, we utilized semitendinosus tendon autograft in meniscus reconstruction to investigate its fibrochondrogenic metaplasticity potential and chondroprotective effect. Tendon-derived stem cells (TDSCs) and synovial-derived mesenchymal stem cells (SMSCs), two most important stem cell sources in our strategy, exhibited excellent viability, distribution, proliferation and fibrochondrogenic differentiation ability in decellularized semitendinosus tendon (DST) scaffolds in vitro. Histologic evaluation of the tendon grafts in vivo suggested endogenous stem cells differentiated into fibrochondrocytes, synthesized proteoglycan, type II collagen and radial type I collagen at 12 weeks and 24 weeks post-surgery. As for elastic modulus and hardness of the grafts, there were no significant differences between native meniscus and regenerated meniscus at 24 weeks. The protection of condylar cartilage from degeneration was significantly better in the reconstruction group comparing to control group. Overall, semitendinosus tendon autograft seems to be a promising substitution in meniscus reconstruction.

Range of motion and complications following primary repair versus reconstruction of the anterior cruciate ligament

INTRODUCTION

Recently, there has been a resurgence of interest in primary anterior cruciate ligament (ACL) repair. The procedure is less invasive than ACL reconstruction, yet studies assessing early postoperative course are lacking. Goal therefore was to assess postoperative range of motion (ROM), complications and operative times following primary repair and compare this to the gold standard of reconstruction.

METHODS

A retrospective study was performed for which 52 repair and 90 reconstruction patients could be included. Patients were examined at one week and one, three and six months. Rehabilitation protocol consisted of early ROM and was equal for both groups. Outcomes were compared using independent t-tests and chi-square tests, and reported in mean±standard deviation.

RESULTS

Repair had more ROM than reconstruction patients at one week (89°±18 vs. 61°±21, p<0.01) and one month (125°±14 vs. 116°±18, p < 0.01) postoperatively. Fewer repair patients had 90° ROM at one week (23% vs. 84%, p<0.01), and more repair patients had full ROM at one month (57% vs. 30%, p<0.01). Treatment of meniscal lesions, but not chondral lesions, influenced ROM. Trends towards fewer complications (2% vs. 9%, p=0.19) and infections (0% vs. 6%, p=0.20) were noted following primary repair, and the procedure was significantly shorter.

CONCLUSIONS

Following primary repair, patients had better ROM, and trends towards fewer complications than reconstruction. Primary repair is a safe, brief procedure with early ROM and low complication rates.

Pectoralis Major Tear with Retracted Tendon: How to Fill the Gap? Reconstruction with Hamstring Autograft and Fixation with an Interference Screw

Rupture of the pectoralis major tendon is considered an uncommon injury and a significant number of ruptures are missed or diagnosed late, leading to a chronic tear. We report an open reconstruction technique and its outcomes in a case of chronic and retracted PM tear. At the last follow-up (12 months), the patient was pain-free, with a visual analogic scale at 0 all the time. He was very satisfied concerning the cosmetic and clinical results. The constant score was 93%, the SST value 95%, and the Quick DASH score 4.5. MRI performed one year postoperatively confirmed the continuity between PM tendon and graft, even if the aspect of the distal tendon seemed to be thinner than normal PM tendon. The excellent clinical outcomes at one-year follow-up suggest that PM tear with major tendon retraction can be reliably reconstructed with hamstring autograft, using a bioabsorbable screw to optimize the fixation device. This technique has proven its simplicity and efficiency to fill the gap.