Metal interference screw fixation combinations show high revision rates in primary hamstring tendon ACL reconstruction.

BACKGROUND: Different fixation methods in anterior cruciate ligament reconstruction (ACLR) have been associated with different revision rates, specifically in the early postoperative period. However, most previous research has either grouped together different fixation types or evaluated femoral-sided fixation or tibial-sided fixation separately. Therefore, the purpose of this study was to determine ACL revision rates for specific combinations of femoral and tibial fixation methods within 2 years of primary hamstring tendon autograft ACLR based on data from the Swedish National Knee Ligament Registry (SNKLR). METHODS: Patients that underwent primary hamstring tendon autograft ACLR between 2005 and 2018 in the SNKLR were included. The collected data included patient characteristics (age, sex, body mass index [BMI]), activity at time of injury, surgical information (concomitant injuries, time from injury to surgery, fixation types at the femur and tibia), and subsequent revision ACLR. Revision rate within 2 years of the index procedure was chosen, as ACLR fixation is most likely to contribute to ACLR revision within the first 2 years, during graft maturation. RESULTS: Of the 23,238 included patients undergoing primary hamstring ACLR, 581 (2.5%) underwent revision ACLR within 2 years of the index procedure. Among the combinations used for > 300 patients, the femoral metal interference screw/tibial metal interference screw fixation combination had the highest revision rate followed by metal interference screw/resorbable screw and Endobutton/AO screw fixation combinations, with respective revision rates of 4.0, 3.0, and 3.0%. The lowest revision rate within 2 years of ACLR was found in the Endobutton/metal interference screw with backup Osteosuture fixation combination, used in 433 cases, with a failure rate of 0.9%. CONCLUSION: Different early ACL revision rates were found across different combinations of femoral and tibial fixation devices within 2 years of primary hamstring tendon autograft ACLR. Metal interference screw fixation, particularly when performed on both the femoral and tibial sides, most frequently resulted in revision ACLR. These findings may be helpful for surgeons in selecting appropriate fixation devices for hamstring ACLR. LEVEL OF EVIDENCE: IV.

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

BACKGROUND: Whether there is a difference in harvesting the semitendinosus tendon alone (S) or in combination with the gracilis tendon (SG) for the recovery of knee flexor strength after anterior cruciate ligament (ACL) reconstruction remains inconclusive. Therefore, this study aimed to assess the recovery of knee flexor strength based on the autograft composition, S or SG autograft at 6, 12, and ≥ 24 months after ACL reconstruction. METHODS: A systematic review and meta-analysis was conducted following the PRISMA guidelines. A comprehensive search was performed encompassing the Cochrane Library, Embase, Medline, PEDRo and AMED databases from inception to January 2023. Inclusion criteria were human clinical trials published in English, comprised of randomized controlled trials (RCTs), longitudinal cohort-, cross-sectional and case-control studies that compared knee flexor strength recovery between S and SG autografts in patients undergoing primary ACL reconstruction. Isokinetic peak torques were summarized for angular velocities of 60°/s, 180°/s, and across all angular velocities, assessed at 6, 12, and ≥ 24 months after ACL reconstruction. A random-effects model was used with standardized mean differences and 95% confidence intervals. Risk of bias was assessed with the RoBANS for non-randomized studies and the Cochrane RoB 2 tool for RCTs. Certainty of evidence was appraised using the GRADE working group methodology. RESULTS: Among the 1,227 patients from the 15 included studies, 604 patients received treatment with S autograft (49%), and 623 received SG autograft (51%). Patients treated with S autograft displayed lesser strength deficits at 6 months across all angular velocities d = -0.25, (95% CI -0.40; -0.10, p = 0.001). Beyond 6 months after ACL reconstruction, no significant difference was observed between autograft compositions. CONCLUSION: The harvest of S autograft for ACL reconstruction yields superior knee flexor strength recovery compared to SG autograft 6 months after ACL reconstruction, irrespective of angular velocity at isokinetic testing. However, the clinical significance of the observed difference in knee flexor strength between autograft compositions at 6 months is questionable, given the very low certainty of evidence and small effect size. There was no significant difference in knee flexor strength recovery between autograft compositions beyond 6 months after ACL reconstruction. TRIAL REGISTRATION: CRD42022286773.

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

PURPOSE: Bone patella-tendon bone (BPTB) and hamstring tendon (HT) autografts are the most used grafts in primary anterior cruciate ligament (ACL) reconstructions (ACLR) in Norway. Quadriceps tendon (QT) autograft has gained more popularity during the past years. The purpose of this study is to compare revision rates and patient-reported outcomes of primary QT with BPTB and HT autograft ACL reconstructions in Norway at 2-year follow-up. It was hypothesized that there would be no difference in 2-year revision rates between all three autografts. METHODS: Data included primary ACLR without concomitant ligament surgeries, registered in the Norwegian Knee Ligament Register from 2004 through 2021. Revision rates at 2 years were calculated using Kaplan-Meier analysis. Hazard ratios (HR) for revision were estimated using multivariable Cox regression analysis with revision within 2 years as endpoint. Mean change in patient-reported outcome was recorded preoperatively and at 2 years through the Knee Injury and Osteoarthritis Outcome Score (KOOS) subcategories 'Sport' and 'Quality of Life' was measured for patients that were not revised and analysed with multiple linear regression. RESULTS: A total of 24,790 primary ACLRs were identified, 10,924 with BPTB, 13,263 with HT and 603 with a QT graft. Patients in the QT group were younger (23.5 years), more of them were women (58.2%) and over 50% had surgery <3 months after injury. The QT group had the highest prevalence of meniscal injuries (61.9%). Revision estimates at 2-years were 3.6%, 2.5% and 1.2% for QT, HT and BPTB, respectively (p < 0.001). In a Cox regression analysis with QT as reference, BPTB had a lower risk of revision (HR 0.4, 95% Cl 0.2-0.7, p < 0.001). No significant difference was observed in the revision risk between QT and HT (HR 1.1, 95% Cl 0.7-1.8, n.s.). The two most common reported reasons for revision were: traumatic graft rupture and nontraumatic graft failure. There were no differences between the groups in change of KOOS in subcategories 'Sport' and 'Quality of Life' at 2-years follow-up. CONCLUSION: The 2-year risk of revision after ACLR with QT was higher than BPTB and similar to HT. No difference was found between the groups in patient-reported outcomes. This study provides valuable insights for both surgeons and patients when making decisions about the choice of autografts in primary ACL reconstructions. LEVEL OF EVIDENCE: Level II.

No difference in clinical outcome between quadriceps tendon anterior cruciate ligament reconstruction with and without bone block: Results from the Danish Knee Ligament Registry.

PURPOSE: The quadriceps tendon (QT) has recently gained increasing interest as an anterior cruciate ligament reconstruction (ACLR) graft due to minimally invasive harvesting techniques and low donor site morbidity. QT grafts can be used both with a patella bone block and as complete soft tissue grafts. However, it is unknown whether the QT graft type affects clinical outcomes. This study used data from the Danish Knee Ligament Reconstruction Registry (DKRR) to compare revision rates, knee stability and subjective clinical outcomes in patients who underwent ACLR with QT graft with bone block (QT-B) or soft tissue only (QT-S). METHODS: Patients who underwent primary ACL reconstruction with QT autografts documented in the DKRR were included and divided into the QT-B (n = 925) and QT-S (n = 659) groups. The clinical outcome was evaluated using objective-instrumented knee stability, pivot shift test, knee injury osteoarthritis outcome score (KOOS) and Tegner activity scores for the two cohorts performed at the 1-year follow-up. The overall revision rates were determined as well. RESULTS: Revision rates at 2 years were equally low in both graft groups at 2.8%. Similarly, post-operative knee laxity was equal at 1.5 (1.4) and 1.6 (1.4) mm side-to-side laxity, respectively. However, QT-B exhibited a reduced post-operative positive pivot shift of 22% compared with 31% for QT-S. Although the subjective outcomes were equal for the KOOS and Tegner activity scale scores at the 1-year follow-up, reduced improvements in KOOS were observed for QT-B compared to QT-S. CONCLUSION: ACL with a QT autograft harvested either with a bone block or as a soft tissue graft exhibited comparable revision rates and sagittal knee stability. Furthermore, ACL reconstruction using a QT graft with a bone block achieved better rotational stability with less pivot shift than ACL reconstruction using complete soft tissue QT grafts. LEVEL OF EVIDENCE: Level III.

Midterm outcomes of autologous bridging of rotator cuff tears with an autologous tendon patch (TEAR patch).

BACKGROUND: Large and massive rotator cuff tears and tears after failed surgical repair are a challenging clinical problem with different treatment options. The purpose of the study was to evaluate the midterm outcomes after rotator cuff repair (RCR) with autologous hamstring tendon graft bridging (tissue-enhanced autologous rotator cuff repair [TEAR] patch) with the hypothesis that outcomes would be reasonable and complication rates would be low. METHODS: This is a retrospective case series study of patients who underwent open RCR using a TEAR patch from June 2015 to March 2019. The exclusion criteria included evidence of cuff tear arthropathy, advanced fatty infiltration, moderate-to-severe arthropathy, and workers compensation board or litigation involved. Clinical outcome measures were Constant score; Disabilities of the Arm, Shoulder and Hand score; Simple Shoulder Test; Subjective Shoulder Value; range of motion (ROM); and manual muscle test for forward elevation, abduction, external and internal rotation, patient satisfaction, and willingness to perform the operation again. Radiographic outcome measures were magnetic resonance imaging, ultrasound, and radiographs: graft integrity and acromiohumeral distance (AHD). RESULTS: A total of 44 patients were followed (89%) for ≥2 years (45 shoulders, mean age 60.3 years [48-76 years], mean follow-up 4.3 years [2-6 years]). All clinical outcome measures (Constant score, Disabilities of the Arm, Shoulder and Hand score, Simple Shoulder Test, Subjective Shoulder Value, ROM, and manual muscle test) demonstrated significant improvement except active external and internal rotation. At 2 years of follow-up, the mean patient satisfaction was high (12.2 of 15 points), and 33 of 38 patients (73.3%) would perform the operation again. A perfect graft integration was observed in 30 (66.7%), a small gap in 7 (15.6%), a retear in 3 (7%), and a complete failure of the tendon patch in 5 (11%) patients. Graft integrity was strongly correlated with the postoperative AHD (r = 0.599, P = .001) and the gain in AHD (r = 0.599, P = .001) but not with ROM or patient-reported outcome measures or patient satisfaction. Four patients required revision surgeries (3 due to deep infection and 1 for poor function and pain). CONCLUSIONS: Midterm clinical and radiographic outcomes after RCR with graft bridging using a TEAR patch were reasonable. The procedure resulted in improved shoulder function and a high level of patient satisfaction. The revision rate is acceptable in view of the specific patient group and treatment alternatives. The described technique of the TEAR patch can be a valuable alternative to existing methods and a new autograft source for rotator cuff surgeries that need bridging of a tendon defect.

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

INTRODUCTION: Anterior cruciate ligament (ACL) reconstruction is one of the most common surgical procedures worldwide. However, the ideal graft source is still debatable. This study compared hamstring (HT) and bone-free quadriceps (QT) tendon autografts in terms of muscle strength and patient-reported outcomes. METHODS: Between June 2018 and December 2019, 46 patients were enrolled in the study and randomly assigned to one of two groups for the ACL reconstruction surgery-the HT autograft group or the QT autograft group. An experienced examiner performed preoperative and postoperative examinations. The HUMAC NORM isokinetic machine (Computer Sports Medicine International-CSMI, 2004) was used to assess flexor and extensor thigh muscle strength. Both groups received the same surgical technique and fixation method. All patients were examined after three, six, nine, and 12 months. The final evaluations were performed at the 24-month follow-up. Patients' scores on the International Knee Documentation Committee (IKDC) evaluation form and the Lysholm Knee Scoring Scale were used to evaluate patient-reported outcomes. The two groups were also compared in terms of postoperative complications and activity levels. RESULTS: The difference between preoperative and postoperative knee flexor peak torques (FPT) was lower in the QT group than in the HT group. The average difference between preoperative and postoperative knee extensor peak torque (EPT) was higher in the QT group than in the HT group. As a result, the HT group had a lower postoperative H/Q ratio (flexor strength normalized to body mass divided by extensor strength normalized to body mass) than the QT group (p < 0.001). The mean IKDC scores for the HT and QT groups were 90.13 ± 6.99 and 87.12 ± 6.61, respectively. The scores of the two groups postoperatively were close, and both groups showed significant improvement. The average graft size in the QT group was significantly greater than that in the HT group. Saphenous nerve palsy was the most common complication in the HT group (22%). Thigh hematomas were observed in two patients in the QT group and required urgent intervention (12%). CONCLUSION: After ACL reconstruction, we found a significant decrease in strength at the donor sites in both techniques, with similar patient-reported measures and stability outcomes. The H/Q strength ratio was higher in the QT group postoperatively, which may have a protective effect on the reconstructed ligament. Level of Evidence I It is a randomized controlled trial.

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

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

Height is a predictor of hamstring tendon length and ACL graft characteristics in adolescents.

BACKGROUND: Knowing the potential hamstring tendon length is relevant for planning ligament reconstructions in children and adolescents, as it is not uncommon to encounter small hamstring tendons intraoperatively. The aim of this study is to predict semitendinosus and gracilis tendon length based on anthropometric values in children and adolescents. The secondary aim is to analyse hamstring tendon autograft characteristics in a closed socket anterior cruciate ligament reconstructions and to evaluate the relationship with anthropometric variables. The hypothesis of this study was that height is predictor of hamstring tendon length and thereby graft characteristics. METHODS: This observational study included two cohorts of adolescents undergoing ligament reconstructions between 2007-2014 and 2017-2020. Age, sex, height and weight were recorded preoperatively. Semitendinosus and gracilis tendon length and graft characteristics were measured intraoperatively. Regression analysis was performed on tendon length and anthropometric values. Subgroup analyses of the closed socket ACL reconstruction were performed and the relation between anthropometric values and graft characteristics were analysed. RESULTS: The population consisted of 171 adolescents from 13 to 17 years of age, with a median age of 16 years [IQR 16-17]. The median semitendinosus tendon length was 29 cm [IQR 26-30] and gracilis tendon length was 27 cm [IQR 25-29]. Height was a significant predictor of semitendinosus and gracilis tendon length. Subgroup analysis of the closed socket ACL reconstructions showed that in 75% of the procedure, the semitendinosus tendon alone was sufficient to create a graft with a minimum diameter of 8.0 mm. CONCLUSIONS: Height is a significant predictor of semitendinosus and gracilis tendon length in adolescents between 13 and 17 years of age and outcomes are similar to data in adults. In 75% of the closed socket ACL reconstructions, the semitendinosus tendon alone is sufficient to create an adequate graft with a minimum diameter of 8 mm. Additional use of the gracilis tendon is more often necessary in females and shorter patients.

No difference in patient reported outcomes, laxity, and failure rate after revision ACL reconstruction with quadriceps tendon compared to hamstring tendon graft: a systematic review and meta-analysis.

PURPOSE: The purpose of this study was to synthesize and quantitatively assess the outcomes of ACL Revision using a quadriceps tendon (QT) graft and to compare them with those of ACL Revisions performed with hamstring tendons (HT) graft. METHODS: A comprehensive search based on the PRISMA protocol was performed across PubMed, Scopus, Embase, and Cochrane Library from inception until February 2022. Clinical studies reporting the outcomes of ACL Revision with QT autograft were included. Subjective and Objective IKDC, Tegner activity level, Lysholm knee score, KOOS score, VAS for pain, knee laxity (KT-1000/2000 arthrometer, Lachman test, and pivot-shift test), and graft failure were assessed. A systematic review and meta-analysis were performed and a quality assessment of the included studies was carried out with the MINORS score. RESULTS: Seven studies met the selection criteria and were included in the systematic review for the qualitative synthesis of data. A pooled mean of all the variables was provided for the 7 studies, while 3 studies included a control group of ACL Revision with HT and were included in a meta-analysis. A total of 420 participants with a mean age of 28.9 ± 10.5 years and a mean postoperative follow-up of 39.3 ± 16.4 months were assessed. Of these, 277 patients underwent ACL Revision with QT and 143 patients underwent ACL Revision with HT. In the QT group, average graft failure was 9.8% compared to 17.4% in the HT group. KOOS Sport and pivot-shift test showed better postoperative outcomes in QT than HT, although it was not statistically significant (p = 0.052). CONCLUSION: The QT autograft was associated with an improved trend of rotatory laxity, PROMs and failure rate compared to HT autograft after revision ACL reconstruction. The QT autograft for revision ACL reconstruction is supported by the current literature. It is a viable graft that should be considered for both primary and revision ACL reconstruction. LEVEL OF EVIDENCE: Level IV.

Quadriceps tendon autograft has similar clinical outcomes when compared to hamstring tendon and bone-patellar tendon-bone autografts for revision ACL reconstruction: a systematic review and meta-analysis.

PURPOSE: Research regarding revision anterior cruciate ligament reconstruction (RACLR) with quadriceps tendon (QT) autografts is lacking. The purpose of this study was to perform a systematic review and meta-analysis of RACLR with QT and compare its patient outcomes to RACLR with hamstring tendon (HT) and bone-patellar tendon-bone (BTB) autografts. METHODS: Adhering to PRISMA guidelines, a search for studies using QT in RACLR was performed within PubMed, Scopus, and CINAHL from database date of inception through December 26, 2022. Primary outcomes sought included: failure rate, Lysholm scores, International Knee Documentation Committee (IKDC) scores, IKDC grades, arthrometric knee side-to-side differences (STSD), pivot shift grade, donor site morbidity, return to sport, visual analog scale (VAS) pain scores. RESULTS: Nine studies were included consisting of 606 RACLR: 349 QT, 169 HT, and 88 BTB. Overall failure rates were 7.6% QT, 13.3% HT, and 8.7% BTB. Mean weighted Lysholm scores were 85.8 ± 3.8 QT, 82.5 ± 3.8 HT and 86.6 ± 4.5 BTB. IKDC average scores were 82.3 ± 1.6 QT, 80.1 ± 1.7 HT, and 81.7 ± 5.5BTB. Combined rates of IKDC A/B grades were 88.4% and 80.0% for QT and HT, respectively. VAS average scores were 0.9 ± 1.1 QT, 1.4 ± 0.2 HT, and 0.7 ± 0.8 for BTB. Side-to-side difference was reported for QT and HT with average values of 1.7 ± 0.6 mm and 2.1 ± 0.5 mm, respectively. Grade 0 or 1 pivot shifts were reported in 96.2% of QT patients and 91.3% of HT. Donor site morbidity, only reported for QT and HT, was 14.6 ± 9.7% and 23.6 ± 14.1%, respectively. QT resulted in a mean Tegner score of 5.9 ± 1.5 versus HT 5.7 ± 1.5. Rate of return to pivoting sports was 38.0% QT, 48.6% HT, and 76.9% BTB. Across all outcomes, there was no significant difference when comparing QT to HT, QT to BTB, and QT compared to HT and BTB combined. CONCLUSIONS: RACLR with QT yields satisfactory patient reported outcomes, satisfactory improvement in knee laxity, expected return to sport rates, and has an overall 7.6% failure rate. Outcomes are comparative to those of HT and BTB making it an acceptable graft choice for RACLR. Surgeons should consider using QT autograft for RACLR, especially when other autografts are unavailable. LEVEL OF EVIDENCE: IV.

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.

Quadriceps tendon autograft is comparable to hamstring tendon and bone-patella-tendon-bone up to 2 years after isolated primary anterior cruciate ligament reconstruction.

PURPOSE: To evaluate the functional and graft survivorship outcomes of the three most common autograft options for primary anterior cruciate ligament reconstruction (ACLR)-hamstring tendon (HT), bone-patella-tendon-bone (BPTB), and quadriceps tendon (QT). METHODS: Patients captured by the New Zealand ACL registry who underwent a primary ACLR from 2014 to 2020 were considered for the study. Patients with associated knee injury (including meniscus, chondral, osseous, and additional ligamentous injury) and previous knee surgery were excluded. Comparison was made between HT, BPTB, and QT autografts with respect to Marx and KOOS (Knee Osteoarthritis Outcome Score) scores at minimum 2 years follow-up. In addition, graft survivorship was evaluated by comparing all-cause revision per 100 graft years and revision-free proportion at 2 years post-surgery. RESULTS: 2,582 patients (1,921 HT, 558 BPTB, 107 QT) were included in the study. Differences in adjusted functional outcomes between HT and BPTB were found at 12 months (mean Marx; HT 6.2; BPTB 7.1; P < 0.001) (mean KOOS Sport and Recreation; HT 75.1; BPTB 70.5; n.s.) and 24 months (mean KOOS Sports and Recreation; HT 79.2; BPTB 73.9; P < 0.001). QT was comparable to HT and BPTB in all functional scores at 12 months and 2 years. No statistically significant differences were found in revision rate between all three autograft groups up to 2 years post-surgery (revision rate per 100 graft years; HT 1.05; BPTB 0.80; QT 1.68; n.s. HT vs. BPTB; n.s. HT vs. QT; n.s. QT vs. BPTB). CONCLUSIONS: QT was found to be comparable to both HT and BPTB in all functional scores and revision rates up to 2 years post-surgery. LEVEL OF EVIDENCE: Level III.

Comparison of "ligamentization" process between preserved insertion hamstring tendon autograft and bone-patellar tendon-bone autograft.

BACKGROUND: Ligamentization is a complex process and effect of preservation of hamstring tendon graft insertion on this process is not well studied. Present study was conducted to analyze and compare the ligamentization of semitendinosus gracilis graft with preserved tibial insertion (STGPI) and bone-patellar tendon-bone (BPTB) autografts. METHODS: A total of 50 sportspeople who underwent ACL reconstruction using either BPTB (group A; n = 25) or STGPI (group B; n = 25) autografts were included in the study. Contrast enhanced MRI was done at 8 months and 14 months post-ACL reconstruction to evaluate the ligamentization using Signal noise quotient (SNQ), graft intensity and enhancement index. Clinical outcomes (Lysholm score) and knee laxity were also assessed at 8 months and 14 months. RESULTS: 18/23 (78%) patients in group A and 14/23 (61%) patients in group B had hyperintense graft signal at 8 months (n.s.) and at 14 months, 1/23 patients in group A and none of the patients in group B had hyperintense graft. SNQ at 8 months was 3.6 ± 2 and 3.7 ± 2 in group A and B respectively (n.s.) and at 14 months, SNQ was 2.5 ± 1.5 in group A and 2.4 ± 1.3 in group B (n.s.). Enhancement index at 8 months was 1.5 ± 0.3 and 1.2 ± 0.3 in group A and B respectively (p = 0.0001). Enhancement index at 14 months was 1.21 ± 0.2 in group A and 1.07 ± 0.2 in group B (p = 0.003). Functional outcomes and knee laxity were comparable in both the groups at 8 and 14 months (n.s.). CONCLUSION: Both the grafts i.e. BPTB and STGPI are similar in terms of rate and extent of ligamentization. Clinical outcomes and knee laxity are also comparable between two grafts.

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.

Full thickness quadriceps tendon grafts with bone had similar material properties to bone-patellar tendon-bone and a four-strand semitendinosus grafts: a biomechanical study.

PURPOSE: Despite increasing interest in utilizing quadriceps tendon (QT) grafts in anterior cruciate ligament reconstruction (ACLR), data on the optimal quadriceps graft thickness are limited. The purpose of this study was to characterize the mechanical properties for the quadriceps tendon, comparing full-thickness (FT) QT grafts with and without bone to a partial-thickness (PT) QT graft, and comparing the three QT grafts to four-stranded semitendinosus (4-SST) and bone-patellar tendon-bone (BTB) grafts and one experimental graft, the two-stranded rectus femoris (RF). METHODS: Forty-eight (n = 48) young cadaveric grafts (mean age 32 ± 6 years) were utilized for testing with N = 8 specimens in each of the following groups; (1) FT QT with bone, (2) FT QT without bone, (3) PT QT without bone, (4) BTB, (5) RF, and (6) 4-SST. Each specimen was harvested and rigidly fixed in custom clamps to a dynamic tensile testing machine for biomechanical evaluation. Graft ultimate load and stiffness were recorded. Independent groups one-factor ANOVAs and Tukey's pairwise comparisons were performed for statistical analyses. RESULTS: FT QT with bone and 4-SST grafts demonstrated similar ultimate loads to BTB grafts (both n.s), whereas PT QT demonstrate statistically significantly lower ultimate loads to BTB grafts (n.s) and 4-SST grafts (n.s). Furthermore, no statistically significant differences were observed between the ultimate loads of FT QT vs. PT QT grafts without bone (n.s) or between FT QT with vs. without bone (n.s). FT QT grafts with bone did not demonstrate statistically significantly greater ultimate loads than PT QT grafts without bone (n.s). The RF graft demonstrated statistically significantly lower ultimate loads to BTB grafts (p < 0.005) and 4-SST grafts (p < 0.014). CONCLUSIONS: Full thickness QT grafts with bone had similar material properties to BTB and a 4-SST grafts, while Partial thickness QT graft without bone had significantly lower material properties than BTB and 4-SST, in a biomechanical setting.

Sufficient MRI graft structural integrity at 9 months after anterior cruciate ligament reconstruction with hamstring tendon autograft.

PURPOSE: To assess the MRI-measured structural integrity of hamstring autograft at 9 months after anterior cruciate ligament reconstruction (ACLR) surgery. METHODS: A prospective cohort study was conducted including 34 patients (mean age 36.8 ± 11.8 years; 73.5% males) who underwent ACLR with hamstring autograft. In addition, 36 patients (mean age 39.2 ± 10.5 years; 69.4% males) without any ACL injury were also reviewed and served as control group. The primary outcome used for examining graft maturity at 9 months after ACLR was the MRI-based signal-to-noise quotient (SNQ) of reconstructed ACL. SNQ values were stratified into 3 different categories: excellent: < 0.1; good: ≥ 0.1 and ≤ 0.19; fair: ≥ 0.2. The KT-1000 knee arthrometer was used to measure the side-to-side difference in the anterior tibial translation between the ACLR knee and the contralateral healthy knee in the ACLR group. RESULTS: Reconstructed ACLs were found with a mean SNQ of 0.078 ± 0.061, while almost all ACL-reconstructed patients (97%; 33 out of 34) were found with excellent or good SNQ values (< 0.019). The mean KT-1000 in the ACLR group was 0.071 mm ± 0.926 mm, while there were no patients in the ACLR cohort with a KT-1000 value > 3 mm. The mean 9-months MRI-based SNQ of ACLR group was significantly higher compared to the mean MRI-based SNQ of the control group (p < 0.001). Multiple regression analysis showed no correlation between SNQ and age, gender, time from injury to ACLR, graft size, or simultaneous treatment of additional intra-articular knee lesions. CONCLUSIONS: In this cohort of 34 ACL-reconstructed patients, 97% of hamstring tendon autografts demonstrated excellent/good MRI signal intensity and excellent functional results (KT-1000 < 3 mm) at 9 months after surgery. Based on this finding, it is suggested that return to sports after ACLR with hamstring autograft can be considered safe at 9 months post surgery. Furthermore, while structural integrity of the graft has been achieved at this time point, statistical differences found in SNQ values of ACL-reconstructed patients compared to ACLs of healthy individuals highlight the continuing process of graft maturation and remodelling. LEVEL OF EVIDENCE: Level III.

A prospective comparison of 3 hamstring ACL fixation devices-rigidfix, bioscrew, and intrafix-randomized into 4 groups with a minimum follow-up of 5 years.

BACKGROUND: ACL (anterior cruciate ligament) reconstruction remains the gold standard surgical option for patients with ACL tears. There are many fixation devices available for ACL reconstruction. Recent ACL reconstruction strategies are aiming to reproduce the native anatomy and normal kinematics of the knee. This is a five years follow-up report of some of the new devices for graft fixation. A two years follow-up data was published previously. METHODS: 120 patients were randomized into four different groups (30 each) for ACL reconstruction with hamstring tendons: group I femoral Rigidfix cross-pin and Intrafix tibial extension sheath with a tapered expansion screw; group II Rigidfix femoral and BioScrew interference screw tibial fixation; group III BioScrew femoral and Intrafix tibial fixation; group IV BioScrew fixation into both tunnels. The evaluation methods were clinical examination, knee scores, and instrumented laxity measurements. RESULTS: In this 5 years follow-up there were 102/120 (85%) patients available, but only 77 (64,2%) attended the clinical examinations. No significant difference between the groups in the clinical results was detected. Between the 2 and 5 years follow-up there were 6 additional procedures in group I and one in group II. There was a significant difference in additional procedures between group I and the other groups (P = .041). CONCLUSION: There was a statistically significant difference in the additional procedures, most in group I (six). The ACL grafts were intact. Other statistically or clinically significant differences in the 5 years follow-up results were not found. STUDY DESIGN: Randomized controlled clinical trial; Level of evidence, 1. Trial registration ISRCTN registry with study ID ISRCTN34011837. Retrospectively registered 17.4.2020.

Age-related differences in hamstring tendon used as autograft in reconstructive anterior cruciate ligament surgery.

PURPOSE: The hamstring tendon is the most commonly used autograft material in reconstructive surgeries of anterior cruciate ligament (ACL) tears. Younger patients have worse surgical outcomes, with a higher risk of re-rupture. We hypothesized that age-related changes in hamstring tendon properties affect the tendon's propensity to rupture when used as an autograft in ACL reconstructions. The purpose of this study was to compare hamstring tendon samples obtained from people aged 20 years or younger to samples obtained from older people. METHODS: Superfluous hamstring tendon material was collected from 13 young donors (aged 16-20 years) and 17 older donors undergoing ACL reconstructive surgery. Sections of the tendon samples were used for biomechanical testing, structural analysis of collagen fibrils by electron microscopy, and global analysis of gene expression by microarrays. RESULTS: We found that tendon samples from the older group had lower Young's modulus than the younger group (P = 0.015), whereas the stress to failure was similar in the two groups. We found no difference in the average diameter of collagen fibrils between the two groups. Microarray analysis identified 162 differentially expressed genes (fold change ≥ 1.5, P < 0.05), with overrepresentation of several biological processes, including regulation of adhesion, migration, inflammation, and differentiation (fold enrichment > 2.0, false discovery rate P < 0.05). CONCLUSION: The hamstring tendon from younger people has higher stiffness than tendon from older people, and the profile of gene expression in tendon varies with age. These differences may negatively affect the performance of the hamstring tendon in ACL reconstructions in younger people.

Quadriceps and hamstring tendon autografts in ACL reconstruction yield comparably good results in a prospective, randomized controlled trial.

INTRODUCTION: Comparable data of functional outcomes of anterior cruciate ligament reconstruction using either hamstring- or quadriceps tendon grafts is controversial. This prospective, randomized controlled trial aims to provide data comparing both grafts regarding the functional outcome. MATERIALS AND METHODS: A two centre trial involving symptomatic patients 18 years of age or older with an anterior cruciate ligament tear was conducted. We randomly assigned 27 patients to quadruple hamstring tendon reconstruction and 24 to quadriceps tendon reconstruction. The patients were evaluated preoperatively, at 3, 6, 12 and 24 months post-surgery. The primary outcome parameter was the side-to-side knee laxity measured with an arthrometer. Secondary outcomes included results in the International Knee Documentation Committee (IKDC) and Lysholm Scores and isokinetic testing of strength in knee extension and flexion. RESULTS: Forty-four patients (86%) completed the 2-year follow-up. There was significantly improved knee stability at all time intervals with no difference between the two study groups. The manual side-to-side displacement improved by 4.7 ± 3.0 mm in patients with hamstring tendon reconstruction and 5.5 ± 2.9 mm in patients with quadriceps tendon reconstruction. In addition, muscle strength and outcome scores (IKDC and Lysholm Score) did not show any differences between the hamstring tendon group and the quadriceps tendon group. Patients in the hamstring tendon group returned to their pre-injury activity level after 95.2 ± 45.5 days while patients in the quadriceps tendon group needed 82.1 ± 45.6 days. CONCLUSION: Quadriceps and hamstring tendon autografts yield comparably good results in primary anterior cruciate ligament reconstruction.

Adjustable-Loop Cortical Suspensory Fixation Results in Greater Tibial Tunnel Widening Compared to Interference Screw Fixation in Primary Anterior Cruciate Ligament Reconstruction.

Background: Although the use of adjustable-loop suspensory fixation has increased in recent years, the influence of the shortcomings of suspensory fixation, such as the bungee-cord or windshield-wiper effects, on tunnel widening remains to be clarified. Hypothesis/Purpose: The purpose of this study was to compare adjustable-loop femoral cortical suspensory fixation and interference screw fixation in terms of tunnel widening and clinical outcomes after anterior cruciate ligament reconstruction (ACLR). We hypothesized that tunnel widening in the adjustable-loop femoral cortical suspensory fixation (AL) group would be comparable to that in the interference screw fixation (IF) group. Methods: This study evaluated patients who underwent primary ACLR at our institution between March 2015 and June 2019. The femoral and tibial tunnel diameters were measured using plain radiographs in the immediate postoperative period and 2 years after ACLR. Tunnel widening and clinical outcomes (Lysholm score, 2000 International Knee Documentation Committee subjective score, and Tegner activity level) were compared between the two groups. Results: There were 48 patients (mean age, 29.8 ± 12.0 years) in the AL group and 44 patients (mean age, 26.0 ± 9.5 years) in the IF group. Tunnel widening was significantly greater in the AL group than that in the IF group at the tibia anteroposterior (AP) middle (2.03 mm vs. 1.32 mm, p = 0.017), tibia AP distal (1.52 mm vs. 0.84 mm, p = 0.012), tibia lateral proximal (1.85 mm vs. 1.00 mm, p = 0.001), tibia lateral middle (2.36 mm vs. 1.03 mm, p < 0.001), and tibia lateral distal (2.34 mm vs. 0.85 mm, p < 0.001) levels. There were no significant differences between the two groups with respect to femoral tunnel widening and clinical outcomes. Conclusions: Tibial tunnel widening was significantly greater in the AL group than in the IF group at 2 years after primary ACLR. However, the clinical outcomes in the two groups were comparable at 2 years.