Hamstring Autograft Research Articles

Peroneus Longus vs Hamstring Tendon Autografts in ACL Reconstruction: A Comparative Study of 106 Patients' Outcomes.

BACKGROUND Anterior cruciate ligament (ACL) reconstruction commonly uses a hamstring tendon autograft, but the peroneus longus tendon can also be used. This study aimed to compare outcomes of anterior cruciate ligament reconstruction in 106 patients using peroneus longus tendon and hamstring tendon autografts. MATERIAL AND METHODS ACL repair was performed on 54 patients using a hamstring tendon autograft and 52 patients with a peroneus longus tendon autograft. Knee function was assessed using the International Knee Documentation Committee (IKDC) and Lysholm scores, while the ankle was evaluated using the American Orthopedic Foot and Ankle Score (AOFAS) and the Foot &amp; Ankle Disability Index (FADI) scores. Donor-site morbidity and graft characteristics were compared. RESULTS There was no difference between the 2 groups in terms of knee IKDC and Lysholm scores (p=0.49, p=0.68, respectively). The diameter of the peroneus longus tendon graft (8.56±0.93) was significantly larger than the hamstring tendon (7.44±0.6) (p<0.001). The peroneus graft harvesting time was significantly shorter (p<0.001). Thigh hypotrophy and donor-site morbidity were significantly higher in the hamstring group (p<0.001 and p=0.006). The donor ankle AOFAS score was 93.46±3.8, and the FADI score was 93.48±4.6. No morbidity associated with the peroneus longus graft was observed. CONCLUSIONS Patients who underwent ACL reconstruction using the peroneus longus tendon experienced faster knee rehabilitation and less donor-site morbidity, such as thigh hypotrophy and knee pain. The peroneus longus tendon, with its larger diameter, fewer graft-related complications, and similar knee scores compared to the hamstring group, is considered a suitable alternative graft source.

Evaluating Gait with Force Sensing Insoles 6 Months after Anterior Cruciate Ligament Reconstruction: An Autograft Comparison.

Aberrant knee mechanics during gait 6 months after anterior cruciate ligament reconstruction (ACLR) are associated with markers of knee cartilage degeneration. The purpose of this study was to compare loading during walking gait in QT, bone-patellar tendon-bone (BPTB), and hamstring tendon (HT) autograft patients 6 months post-ACLR using loadsol single sensor insoles, and to evaluate associations between loading and patient reported outcomes. 72 patients (13-40 years) who underwent unilateral, primary ACLR with BPTB, QT, or HT autograft completed treadmill gait assessment, the International Knee Documentation Committee (IKDC) survey and the ACL-Return to Sport after Injury (ACL-RSI) survey 6 ± 1 months post-ACLR. Ground reaction forces were collected using loadsols. Limb symmetry indices (LSI) for peak impact force (PIF), loading response instantaneous loading rate (ILR), and loading response average loading rate (ALR) were compared between groups using separate ANCOVAs. Survey scores were compared between groups using one-way ANOVAs. The relationships between IKDC, ACL-RSI, and LSIs were compared using Pearson's product moment correlation coefficients. There were no significant differences between graft sources for LSI in PIF, ILR, ALR, nor impulse. Patient-reported knee function was significantly different between graft source groups with the BPTB group reporting the highest IKDC scores; however, there was no significant difference between groups for ACL-RSI score. There were no significant associations between IKDC score, ACL-RSI score, and biomechanical symmetry among any of the graft source groups. Autograft type does not influence PIF, ILR, ALR, or impulse during walking 6 months post-ACLR. Limb symmetry during gait is not strongly associated with patient reported outcomes regardless of graft source. Loadsols appear to be a suitable tool for use in the clinical rehabilitation setting.

Predictors of Clinical Outcomes and Quality of Life After Sternoclavicular Joint Reconstruction With Hamstring Tendon Autograft

Background: Anterior instability of the sternoclavicular joint (SCJ) is a rare but potentially devastating pathological condition, particularly when it occurs in young or active patients. SCJ reconstruction using hamstring tendon autograft is a commonly used treatment option, yet to date results are limited to small case series. Studies on baseline, preoperative factors and their association with postoperative outcome are limited. Purpose: To assess the midterm clinical outcomes and survivorship after SCJ reconstruction using hamstring tendon autograft in patients experiencing anterior SCJ instability and to determine whether baseline patient or causative factors are associated with postoperative outcomes or patient satisfaction. Study Design: Case series; Level of evidence, 4. Methods: Patients who underwent SCJ reconstruction with a hamstring tendon autograft for anterior SCJ instability between October 2005 and October 2020 were included in this retrospective single-center study. At a minimum of 2 years postoperatively, clinical outcomes were collected, including the following patient-reported outcomes (PROs): the 12-Item Short Form Survey (SF-12) score; American Shoulder and Elbow Surgeons (ASES) score; Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score; Single Assessment Numeric Evaluation (SANE) score; and visual analog scale (VAS) pain score. Subjective postoperative satisfaction with the procedure was quantified on a scale from 0 (very unsatisfied) to 10 (very satisfied). The predictive role of patient factors, including age, sex, and injury in dominant arm, on postoperative PROs and satisfaction at short-term follow-up was evaluated using multiple linear regression. Results: A total of 49 patients (mean age, 29.6 ± 16.2 years; range 13.8-67.1 years; 27 females) were included in the final analysis. At a mean follow-up of 3.9 ± 2.1 years, all PROs had significantly improved, including the mean SF-12 Physical Component Summary score (40.4 ± 6.8 to 52.6 ± 6.9; P < .001), ASES score (54.9 ± 20.4 to 91.0 ± 11.3; P < .001), QuickDASH score (41.2 ± 18.5 to 10.2 ± 9.1; P < .001); SANE score (50.2 ± 21.1 to 88.3 ± 8.8; P < .001), VAS pain score (4.4 ± 2.6 to 0.8 ± 1.4; P < .001), and VAS pain score at its worst (7.4 ± 2.5 to 3.3 ± 2.6; P < .001). The median postoperative satisfaction score was 9 (range, 1-10). Revision-free survivorship was 95.9%. Male patients had a significantly lower VAS pain score at its worst compared with female patients (2.6 ± 2.6 vs 4.1 ± 2.4; P = .045); higher age was significantly correlated with a worse QuickDASH score (correlation coefficient, 0.314; P = .036). Overhead athletes had a significantly lower propensity to return to sport compared with nonoverhead athletes (P = .043), with only 45% of the overhead athletes returning to a level similar to their preinjury level, whereas 81% of the nonoverhead athletes were able to do so. Conclusion: The significant improvements in clinical and sport-specific outcomes and high patient satisfaction after SCJ reconstruction with a hamstring tendon autograft demonstrate the success of this procedure in treating anterior SCJ instability. Male sex and younger patient age are associated with superior outcomes, while overhead athletes have to be counseled about difficulties of returning to preinjury level of sport postoperatively.

Arthroscopic Reconstruction of an Anterior Cruciate Ligament Tear Using the Anatomic Single-Bundle Technique: A Clinical and Functional Outcome Evaluation.

The anterior cruciate ligament (ACL) consists of an anteromedial bundle and a posterolateral bundle giving anteroposterior and rotational stability to the knee. An ACL tear might lead to secondary changes in the knee joint if not operated in time. The aim of the study was to evaluate the clinical and functional results in patients with ACL tears treated by arthroscopic reconstruction using the anatomic single-bundle technique. This was a prospective study conducted between June 2015 and December2017 at a teaching institute in Kolkata, India, on patients who underwent single-bundle arthroscopic reconstruction of an ACL tear. A minimum follow-up of nine months was considered for all patients. The functional outcome was assessed via the Lysholm knee score. A total of 45 patients were included in this study, of which 34 (75.56%) and eight (17.78%) patients showed excellent and good results, respectively, at the final follow-up. The mean age in this study was 29.88±9.02 years. No complication was seen in 95.6% of patients. The mean Lysholm score by the end of nine months was 95.31±6.55. At the time of the final follow-up, all the patients returned to their same activity status prior to injury. Arthroscopic anatomic single-bundle ACL reconstruction using hamstring autograft is an effective treatment modality for ACL injuries. It restores the stability of the knee and is associated with good recovery of joint function with an early return to active lifestyle and sports activities. This procedure achieves excellent clinical and functional outcomes without any long-term disability.

Several factors predict the achievement of the patient acceptable symptom state and minimal clinically important difference for patient-reported outcome measures following anterior cruciate ligament reconstruction: A systematic review.

To summarize the predictors of the patient acceptable symptom state (PASS), minimal clinically important difference (MCID) and minimal important change (MIC) for patient-reported outcome measures (PROMs) following anterior cruciate ligament reconstruction (ACLR). MEDLINE, PubMed and Embase were searched from inception to 5 January 2024. The authors adhered to PRISMA/R-AMSTAR guidelines, and the Cochrane Handbook for Systematic Reviews of Interventions. Data on statistical associations between predictive factors and PROMs were extracted. Inverse odds ratios (ORs) and confidence intervals (reverse group comparison) were calculated when appropriate to ensure comparative consistency. Thirteen studies comprising 21,235 patients (48.1% female) were included (mean age 29.3 years). Eight studies comprising 3857 patients identified predictors of PASS, including lateral extra-articular tenodesis (LET) (OR = 11.08, p = 0.01), hamstring tendon (HT) autografts (OR range: 2.02-2.63, p ≤ 0.011), age over 30 (OR range: 1.37-2.28, p ≤ 0.02), male sex (OR range: 1.03-1.32, p ≤ 0.01) and higher pre-operative PROMs (OR range: 1.04-1.21). Eight studies comprising 18,069 patients identified negative predictors of MCID or MIC, including female sex (OR = 0.93, p = 0.034), absence of HT autografts (OR = 0.70, p < 0.0001), higher pre-operative PROMs (OR = 0.76-0.84, p ≤ 0.01), meniscectomy (OR = 0.67, p = 0.014) and collision sports (OR = 0.02-0.60, p ≤ 0.05). Higher pre-operative PROMs, age over 30, male sex, LETs and HT autografts predicted PASS achievement. Lower pre-operative PROMs, male sex, non-collision sports, and lack of meniscectomies predicted MCID/MIC achievement. This review provides a comprehensive understanding of the predictors of clinically significant post-ACLR outcomes, thus improving clinical decision-making and the management of patient expectations. Level IV.

Comparative Analysis of the Six-Strand Hamstring and Peroneus Longus in Sports Medicine and Rehabilitation

The anterior cruciate ligament (ACL) is crucial for knee stability and is often injured in sports, leading to significant issues like degenerative changes and meniscal tears. ACL tears are prevalent in high-school sports injuries, accounting for 50% of knee injuries in the U.S. Surgical reconstruction, often involving bone-patellar tendon-bone (BPTB) or hamstring autografts, is common, with varying success rates and complications. Emerging alternatives like the peroneus longus tendon show promise but require further comparative studies. This prospective and multicentric study included 110 patients who underwent ACL reconstruction from 2020 to 2022. Fifty-five patients received hamstring tendon autografts (Group H) and fifty-five received peroneus longus tendon autografts (Group P). Surgeries were performed by experienced surgeons using standardized techniques. Patients were evaluated using clinical tests and functional scores including the Lysholm Knee Questionnaire and IKDC-2000 at various postoperative intervals up to 24 months. Data were analyzed using SPSS with a significance level set at p &lt; 0.05. Group H showed superior knee function preoperatively and at 24 months postoperatively compared to Group P. Group H had higher Lysholm and IKDC scores consistently throughout the study period. The anterior drawer and Lachman’s tests indicated better knee stability for Group H. Complications were comparable between groups, with specific issues related to donor site morbidity and muscle weakness observed in each. The six-strand hamstring tendon autograft (Group H) demonstrated superior functional outcomes and knee stability compared to the peroneus longus tendon autograft (Group P) for ACL reconstruction. Despite some donor site morbidity, the hamstring tendon showed better long-term recovery and fewer complications. Future studies should explore larger, multicentric cohorts and integrate regenerative medicine techniques to further enhance ACL reconstruction outcomes.

Comparison of Time Needed to Meet Common Rehabilitation Milestones After Anterior Cruciate Ligament Reconstruction According to Graft Type

Background: The use of bone–patellar tendon–bone (BPTB) and hamstring tendon (HT) autografts is common in anterior cruciate ligament reconstruction (ACLR). After ACLR, patients typically progress through specific rehabilitation milestones, and graft type may play a role in patient progression. Purpose: To compare the time to meet rehabilitation milestones between BPTB and HT autografts after ACLR. Design: Cohort study; Level of evidence, 3. Methods: This was a single-institution study on patients who underwent ACLR with either BPTB or HT autograft between June 2018 and July 2021. The primary outcomes were time to meet return-to-sport criteria, including &gt;90% limb symmetry index (LSI) for isokinetic quadriceps and hamstring strength, horizontal hop, 4-crossover hop, and single-hop height. The time to satisfaction of each criterion was compared between graft groups using Wilcoxon tests and Cox proportional hazards models. Results: Included in the analysis were 410 participants who underwent ACLR with either BPTB (n = 232) or HT (n = 178). The BPTB group took longer to achieve &gt;90% LSI for knee extension than HT (11.1 ± 4.1 vs 7.63 ± 2.8 months; P &lt; .001). Similarly, the BPTB group took longer than the HT group to achieve &gt;90% LSI for horizontal hop (11.4 ± 3.5 vs 9.82 ± 2.8 months; P &lt; .001), 4-crossover hop (11.8 ± 3.6 vs 10.4 ± 2.8 months; P = .002), and single-hop height testing (11 ± 3.7 vs 8.81 ± 3.2 months; P &lt; .001). The median time to achieve &gt;90% LSI for hamstring strength was similar between groups (7.18 ± 3 vs 7.56 ± 3.1 months; P = .2). Conclusion: Patients that underwent ACLR with BPTB autograft took longer than patients with HT to meet commonly used postoperative rehabilitation milestones. Clinicians should consider these differences when guiding patients regarding graft choice, postoperative expectations, and rehabilitation.

Patellar Tendon Debridement and Reconstruction With Hamstring Tendon Autografts in the Setting of Severe Patellar Tendinopathy

Background: Patellar tendinopathy is a multifactorial condition characterized by micro-degenerative changes in the patellar tendon. This results from repeated stress to the knee extensor mechanism from explosive movement, axial malalignment, and/or abnormal patellar height. Currently, there is no standard surgical procedure for the treatment of severe patellar tendinopathy. Indications: Patellar tendon reconstructions for patellar tendinopathy may be indicated when &gt;50% of the tendon attachment is degenerative and detached from the distal patella and non-operative treatment, like physical therapy, bracing, and injections, have not relieved symptoms. Debridement may not offer long-term viability against augmentation of the patellar tendon with autografts, with a risk of recurrent breakdown of the patellar tendon attachment with resumption of previous activities that initially lead to overload. Technique Description: An anterior incision was made from the superior pole of the patella to the tibial tubercle. Then, dissection was performed medially to harvest the gracilis and semitendinosus tendons. Open harvesters were used, and the hamstring tendons were released proximally, keeping the tibial insertions attached. A horizontal pin was drilled across the tibial tubercle and reamed with a 4.5 mm reamer. A passing stitch was fed through the tunnel. The proximal and distal margins of the patella were localized with spinal needles and a pin was drilled across its midportion, 5 mm deep to the dorsal cortical margin, and then rearmed. Degenerative tissue at the patellar tendon was excised. The gracilis tendon was passed medial to lateral through the tibial tubercle, and a Q-Fix anchor anchored the grafts medially and laterally. The semitendinosus graft was passed medial to lateral through the patella followed by the gracilis tendon lateral to medial. Appropriate reconstruction graft tension was confirmed and grafts were whipstitched together. Results: Clinical outcomes for the debridement of severe patellar tendinopathy report 77% symptomatic relief. With many unable to return to activity, patellar tendon reconstruction can be indicated. Outcomes for reconstructions for severe patellar tendinopathy are not reported. Discussion: Patellar tendon reconstruction with hamstring autografts for the treatment of severe patellar tendinopathy can provide a strong reconstruction graft to allow for the resumption of high-level activities. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

MCL Repair, Isolated Suture-Tape-Bracing and No Repair for Grade III MCL Tears During ACL Reconstruction Have Similar Outcome for Combined ACL With MCL Injury: A 3-Arm Randomized Controlled Trial

Aim of the study was to compare various MCL management strategies(repair vs isolated suture-tape bracing vs no repair) combined with ACL reconstruction and analyse results of MCL sub-types (femoral/mid-substance/tibial-sided tears) occurring at distinct levels. This study is a double blinded prospective randomised controlled trial. 96 consecutive patients with combined ACL and grade III MCL between 2020 and 2023 with minimum follow up of 24 months were included in the study. Chronic MCL and other ligament injuries were excluded, and computer-generated randomisation was done for allotment into three MCL management groups. ACL reconstruction with hamstring autograft was performed and MCL treated by repair in group 1(n=33), isolated suture-tape bracing -group 2(n=32) and no repair-group 3(n=31). At follow-up, stress radiographs were utilized to analyse anterior and medial laxity. IKDC, Lysholm, KOOS scores, duration of surgery and cost of surgery were compared. Also, subgroup analysis was performed to assess outcomes based on location of MCL injury. Demographic data, duration of injury, mode of injury and level of MCL injury is similar across groups. Over all MCL tears-femoral side, mid-substance and tibial side were 58.3%,18.7%and 23.0% respectively. Post-operatively significant improvement in ROM and functional score was observed in all three groups(P=<0.05); however, there was no statistically significant difference between the three groups at final follow-up in anterior tibial translation(P=0.94), medial opening in 0°(P=0.8) & 30°(P=0.64), ROM(P=0.39), IKDC(P=0.17), Lysholm(P=0.14) & KOOS(P=0.68). Three patients in group 2 had stiffness at 3months; two were treated with CPM and physiotherapy and 1 patient needed arthrolysis. Medial opening(00 and 300) was greater in group 3- mid-substance MCL tear patients(P=0.042,0.043). On Minimal clinically important differences (MCID) analysis more than 80% of patients had improvement in range of motion, functional scores and medial opening less than 5mm, suggestive of successful outcome in all the three groups. The duration of surgery was longer in repair group(P=0.001), whereas cost was higher in the suture-tape bracing group(P=0.003). Repair, isolated suture-tape bracing and no repair treatments of MCL result in good radiological (medial stress laxity) and functional outcomes when combined with ACL reconstruction. MCL Repair or isolated suture-tape bracing restore better medial side stability. Mid-substance MCL tears may need additional procedure(repair/bracing) to restore medial stability.

Risk for Revision ACLR After Primary All-Inside Quadrupled Semitendinosus Hamstring Tendon Autograft ACLR With Independent Suture Tape Augmentation: A Retrospective Cohort Study.

The rate of failed anterior cruciate ligament reconstruction (ACLR) remains high in the younger and more active patient populations. Suture tape augmentation (STA) in addition to ACLR may reduce the risk for revision surgery. The purpose of this study was to compare patient outcomes between patients who underwent primary all-inside quadrupled semitendinosus hamstring tendon autograft (QST-HTA) ACLR with and without STA. It was hypothesized that the STA cohort would demonstrate a lower incidence of subsequent revision ACLR while maintaining comparable patient-reported outcomes. Cohort study; Level of evidence, 3. All patients ≤40 years of age who received primary all-inside QST-HTA ACLR with and without independent STA augmentation were identified. The following validated patient-reported outcome measures (PROMs) were collected: visual analog scale for pain, Single Assessment Numeric Evaluation, Knee injury and Osteoarthritis Outcome Score subscales, and Tegner activity scale. KT-1000 arthrometer measurements were collected pre- and postoperatively. Cox proportional hazards model and nominal logistic regression analysis were used to assess additional variables associated with revision ACLR. A total of 104 patients with a mean age of <22 years were included in the final data analysis (STA: 36 patients; control: 68 patients). Significantly fewer patients in the STA group sustained a graft failure necessitating revision surgery at the final follow-up (5.6% vs 24%; relative risk, 0.24 [95% CI, 0.06-0.97]; P = .017). Four-year graft survival was significantly higher in the STA group (97.2% vs 82.4%; P = .031). All PROMs significantly improved postoperatively except for Tegner levels, which decreased in both groups compared with their preinjury levels (P < .001). Return to sports was similar in both groups with >70% of patients returning to their previous level of competition. Regression analysis demonstrated increased risk for revision ACLR in younger patients, high school athletes, and those with higher postoperative activity levels. QST-HTA ACLR with STA was associated with reduced risk for revision ACLR compared with nonaugmented QST-HTA ACLR in this young patient population. Furthermore, the addition of suture tape did not appear to affect postoperative patient-reported and return-to-sports outcomes.

Presoaking hamstring autograft with vancomycin does not jeopardize its biomechanical properties, including graft elongation, after cyclic loading.

Presoaking the graft with vancomycin before implantation has been shown to reduce the risk of postoperative infection after anterior cruciate ligament reconstruction (ACLR). However, the effects of presoaking on the graft biomechanical properties remain unclear. This study aimed to determine whether presoaking the graft with vancomycin affects the graft biomechanical properties and length after cyclic loading. Ten paired (20 specimens) gracilis and semitendinous tendons were harvested from fresh-frozen human cadaveric specimens. Two tendons were folded in half to make four strands, and the grafts were randomized into the vancomycin and control groups. The graft was exposed to the antibiotic solution for 15 min (5 mg/mL) and prepared by mixing 1 g of vancomycin with 200 mL of normal saline (NaCl 0.9%). The control group was soaked in normal saline for 15 min. The prepared grafts were attached to the actuator of a dynamic tensile-testing machine. All grafts were tested with 3000 cycles of cyclic loading followed by a pull-to-failure. The cyclic loading protocol consisted of position and load control blocks to simulate the graft in vivo in the postoperative phase after ACLR. Presoaking in vancomycin did not jeopardize the biomechanical properties of the graft. In addition, presoaking with vancomycin did not elongate the grafts. No significant differences were found in the mean Young's modulus and the mean total elongation of the graft of the specimen between the vancomycin group and the control group. Presoaking the graft with vancomycin jeopardized neither its biomechanical properties nor elongation even after cyclic loading in this in vitro study. It is suggested that vancomycin presoaking could be considered a safe and effective preventive measure for postoperative infections after ACLR. Not applicable.

No Difference in Graft Signal Intensity on Magnetic Resonance Imaging or Clinical Outcome Between Anterior Cruciate Ligament Reconstruction With and Without Suture Augmentation

PurposeTo evaluate the safety of anterior cruciate ligament reconstruction (ACLR) with suture augmentation (SA) through clinical evaluations, monitoring of complications, and evaluation of early graft remodeling using magnetic resonance imaging (MRI). MethodsData of participants who underwent anatomic double-bundle ACLR using hamstring tendon autografts, with a minimum 2-year follow-up, were retrospectively reviewed. Participants undergoing ACLR with SA were propensity-matched with those without SA. Postoperative clinical evaluations, including Lysholm and Tegner activity scores, International Knee Documentation Committee (IKDC) evaluation scores, KT-1000 side-to-side difference for knee stability at a 2-year follow-up, and complications, were recorded. The minimal clinically important difference (MCID) was calculated for IKDC scores. The anteromedial bundle graft was categorized into distal, middle, and proximal regions on the 6-month and 1-year postoperative MRI. The signal-to-noise quotient (SNQ) of each region of interest was calculated to evaluate the graft signal intensity, which was compared between the two groups using Welch’s t-test. ResultsFifty-three participants were included in each group. No significant differences were observed between the non-SA and SA groups in the Lysholm scores (96.6 ± 6.2; 95.3 ± 5.8, P = 0.25), Tegner activity scores (4.8 ± 1.4; 5.0 ± 1.3, P = 0.49), IKDC scores (90.4 ± 10.8; 87.1 ± 12.9, P = 0.15), percentage of patients meeting the MCID (94.3%; 83.0%, P = 0.12), or postoperative KT-1000 side-to-side difference (0.9 ±1.2; 0.7 ± 1.8 mm, P = 0.56). One (1.8%) and two (3.7%) cases of re-tears occurred in the non-SA and SA groups, respectively; no other complications occurred. The postoperative SNQ measurements revealed no significant differences in signal changes in all regions of the grafts between the two groups. ConclusionsThis study confirmed no difference in graft signal intensity on MRI or clinical outcome between ACLR with and without SA at the 2-year follow-up. Level of EvidenceLevel III, retrospective, comparative study.

Ensemble Algorithm for Risk Prediction of Clinical Failure After Anterior Cruciate Ligament Reconstruction.

Patient-specific risk profiles of clinical failure after anterior cruciate ligament reconstruction (ACLR) are meaningful for preoperative surgical planning and postoperative rehabilitation guidance. To create an ensemble algorithm machine learning (ML) model and ML-based web-based tool that can predict the patient-specific risk of clinical failure after ACLR. Cohort study; Level of evidence, 3. Included were 432 patients (mean age, 26.8 ± 8.4 years; 74.1% male) who underwent anatomic double-bundle ACLR with hamstring tendon autograft between January 2010 and February 2019. The primary outcome was the probability of clinical failure at a minimum 2-year follow-up. The authors included 24 independent variables for feature selection and model development. The data set was split randomly into training sets (75%) and test sets (25%). Models were built using 4 ML algorithms: extreme gradient boosting, random forest, light gradient boosting machine, and adaptive boosting. In addition, a weighted-average voting (WAV) ensemble model was constructed using the ensemble-voting technique to predict clinical failure after ACLR. Concordance (area under the receiver operating characteristic curve [AUC]), calibration, and decision curve analysis were used to evaluate predictive performances of the 5 models. Clinical failure occurred in 73 of the 432 patients (16.9%). The 8 most important predictors for clinical failure were follow-up period, high-grade preoperative knee laxity, time from injury to ACLR, participation in competitive sports, posterior tibial slope, graft diameter, age at surgery, and medial meniscus resection. The WAV ensemble algorithm achieved the best predictive performance based on concordance (AUC, 0.9139), calibration (calibration intercept, -0.1806; calibration slope, 1.2794; Brier score, 0.0888), and decision curve analysis (greatest net benefits) and was used to develop an web-based application to predict a patient's clinical failure risk of ACLR. The WAV ensemble algorithm was able to accurately predict patient-specific risk of clinical failure after ACLR. Clinicians and patients can use the web-based application during preoperative consultation to understand individual prediction outcomes.

Comparing Ultrasound and MRI Evaluations of the Hamstring Tendon for Predicting Autograft Size in Anterior Cruciate Ligament Reconstruction.

Adequate graft size and length are crucial factors in anterior cruciate ligament (ACL) reconstruction. Accurate identification of patients who may be at risk for an insufficient length or size of the hamstring tendon (HT) can aid surgeons in preoperative planning. To evaluate whether magnetic resonance imaging (MRI) or ultrasound could more accurately predict the size of the semitendinosus tendon (ST) and gracilis tendon (GT) and to investigate the correlation between anthropometry, graft size, and imaging measurements to find a predictive formula. Cross-sectional study; Level of evidence, 3. Included in the study were 36 patients who underwent ACL reconstruction with HT autograft at our institution between July 2021 and May 2022. Anthropometric data and MRI and ultrasound measurements were collected preoperatively. The length and diameter of the HT were recorded intraoperatively. Correlations between anthropometry, graft size, and imaging measurements were analyzed. Linear regression analysis was performed to construct a prediction formula. The intraoperative graft diameters of the ST and GT were weakly to moderately associated with their cross-sectional areas as measured by MRI and ultrasound. MRI and ultrasound interpreted 11.9% to 15.7% and 18.4% to 41.7% of the variation in the graft diameter of the HT, with an accuracy of 50.0% to 55.6% and 69.4% to 86.1%, respectively. The intraoperative lengths of the ST and GT were both associated with patient height and tendon lengths as measured by ultrasound. Additionally, intraoperative GT length was associated with patient weight. Four formulas combining relevant anthropometric parameters and imaging measurements were calculated from multilinear regression analysis, explaining up to 46.3% of the variance in the size of HT. Ultrasound and MRI alone showed limited ability to predict the graft diameter of the ST and GT, while ultrasound could more accurately predict the graft size than MRI. Among the different anthropometric variables, height was the most influential in predicting tendon length.

Effect of Preoperative Anterolateral Ligament Injury on Outcomes After Isolated Acute ACL Reconstruction With Hamstring Graft: A Prospective Study With Minimum 5-Year Follow-up

Background: The potential influence of a preoperative anterolateral ligament (ALL) lesion seen on magnetic resonance imaging (MRI) on the mid- and long-term surgical outcomes of anterior cruciate ligament (ACL) reconstruction is still controversial. Purpose: To evaluate the clinical outcomes and failure rate of isolated ACL reconstruction at a minimum 5-year follow-up in patients with and without ALL injury diagnosed preoperatively using MRI. Study Design: Cohort study; Level of evidence, 2. Methods: A prospective cohort of patients with acute ACL injury was divided into 2 groups based on the presence (ALL injury group) or absence (control group) of ALL injury on preoperative MRI. This is a longer-term follow-up study of a previously published study that had a minimum 2-year follow-up. Both groups underwent anatomic isolated reconstruction of the ACL. The Lysholm and subjective International Knee Documentation Committee scores, KT-1000 arthrometer and pivot-shift tests, reconstruction failure rate, incidence of contralateral ACL injury, presence of associated meniscal injury, and presence of knee hyperextension were evaluated. The evaluation at the 5-year follow-up was also compared with the same patient’s evaluation at 2 years of follow-up. Results: A total of 156 patients were evaluated. No significant differences were found between the groups in the preoperative evaluation. In the postoperative evaluation, patients in the ALL injury group had a higher reconstruction failure rate (14.3% vs 4.6% for the control group; P = .049) and worse clinical outcomes according to the Lysholm scores (85.0 ± 10.3 vs 92.3 ± 6.6; P < .00001). Although the pivot-shift test results were similar, anteroposterior translation using the KT-1000 arthrometer revealed worse results for the ALL injury group (2.8 ± 1.4 mm vs 1.9 ± 1.3 mm; P = .00018). Patients in the ALL injury group also had an increase in KT-1000 arthrometer values from 2 to 5 years (2.4 ± 1.6 vs 2.8 ± 1.4; P = .038). Patients in the control group had no differences in outcomes from 2 to 5 years of follow-up. Conclusion: Combined ACL and ALL injuries were associated with significantly less favorable outcomes than were isolated ACL injuries at a minimum follow-up of 5 years after isolated ACL reconstruction with hamstring autograft. Patients with concomitant ALL injury showed a higher failure rate and worse functional scores. Also, knee stability tended to slightly worsen from 2 to 5 years in cases of associated ALL injury.

Patient and Operative Risk Factors for Osteoarthritis After Primary Anterior Cruciate Ligament Reconstruction: A Cohort Study of 41,976 Patients

Background: The reported incidence of posttraumatic knee osteoarthritis (PTOA) after primary anterior cruciate ligament reconstruction (ACLR) varies considerably. Further, there are gaps in identifying which patients are at risk for PTOA after ACLR and whether there are modifiable factors. Purpose: To (1) determine the incidence of PTOA in a primary ACLR cohort and (2) identify patient and perioperative factors associated with the development of PTOA after primary ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: Data from the Kaiser Permanente ACLR Registry were used to conduct a cohort study. Patients who had undergone primary ACLR without a previous diagnosis of osteoarthritis were identified (2009-2020). The crude incidence of PTOA was calculated using the Aalen-Johansen estimator with a multistate model. The association of patient and operative factors with the development of PTOA after primary ACLR was modeled as a time to event using multistate Cox proportional hazards regression. Models stratified by age (<22 and ≥22 years) were also conducted because of the effect modification of age. Results: The study sample included 41,976 cases of primary ACLR. The incidence of PTOA was 1.7%, 5.1%, and 13.6% at 2, 5, and 10 year follow-ups, respectively. Risk factors for PTOA that were consistently identified in the overall cohort and age-stratified groups included a body mass index ≥30 versus <30 and an allograft or quadriceps tendon autograft versus a hamstring tendon autograft. Patients presenting with knee pain after ACLR were further identified when considering postoperative factors. Other risk factors for PTOA in the overall cohort included age ≥22 versus <22 years, bone–patellar tendon–bone autograft versus hamstring tendon autograft, hypertension, cartilage injury, meniscal injury, revision after primary ACLR with concomitant meniscal/cartilage surgery, multiligament injury, other activity at the time of injury compared with sport, and tibial tunnel drilling technique rather than the anteromedial portal. Conclusion: Knee pain after ACLR may be an early sign of PTOA. Surgeons should consider the adverse associations of a higher body mass index and an allograft or quadriceps tendon autograft with the development of PTOA, as these were factors identified with a higher risk, regardless of a patient’s age at the time of primary ACLR.

Outcomes of ACL Reconstruction Utilizing Supercritical CO2-Sterilized Allografts.

Allograft tendons are perceived to have a high ACL graft failure rate in primary anterior cruciate ligament (ACL) reconstruction (ACLR). Historical series may be biased by graft processing methods that degrade the biomechanical properties of donor tendons such as irradiation. Supercritical carbon dioxide (SCCO2) is a validated method of terminally sterilizing biomaterials at physiological temperatures without irradiation, but in vivo use of SCCO2-processed tendon allografts for primary ACLR has not been reported to date. ACLR with SCCO2 allografts would result in acceptable failure rates, subjective knee scores, and clinical evaluation at 2 years postoperatively. Case series; Level of evidence, 4. Patients underwent primary ACLR with terminally sterilized SCCO2-processed human gracilis, peroneus longus, semitendinosus, tibialis anterior, and tibialis posterior tendon allografts. Patient demographics were collected, along with tendon donor age and sex. At 1 year postoperatively, subjective International Knee Documentation Committee (IKDC) and ACL-Return to Sport After Injury (ACL-RSI) scores were collected, as well as clinical evaluation. At 2 years postoperatively, the IKDC and ACL-RSI scores were repeated, and return to sports and further knee injuries were recorded. A total of 144 patients with a medianage of 26 (IQR 14) years formed the study group. Patients were predominately male (58%). The loss to follow-up rate was 8% (n = 12). The mean age of allograft tendon donors was 37 (range 17-58) years, and the majority were male (83%). The mean allograft diameter was 8.9 ± 1.0 mm. At 2 years, ACL graft failureoccurred in 5% (n = 7). All graft failureswere in patients aged ≤25 years (P = .007). Neither donor age (≤40 or >40 years) nor donor sex was associated with graft failure (P > .05). The median IKDC subjective score was 95 and ACL-RSI score was 75. There were no revisions for sepsis within the first 2 years postoperatively. SCCO2 processing of allograft tendons demonstrated satisfactory clinical and patient-reported outcomes at 24 months postoperatively in a consecutive series of patients with primary ACLR, with similar ACL graft failure rates and subjective knee scores compared with those reported in published series of hamstring tendon autograft and fresh frozen nonirradiated allograft.

No Clinically Significant Differences in Outcomes After Anterior Cruciate Ligament Reconstruction When Comparing Quadriceps, Bone–Patellar Tendon–Bone, and Hamstring Autografts of 9 mm or Greater

To determine whether there are patient-reported outcome differences in bone-patellar tendon-bone (BPTB), quadriceps tendon (QT), and hamstring (HS) grafts of comparable size. We performed a retrospective analysis of global registry data to include all patients who had an anterior cruciate ligament reconstruction with BPTB, QT, or HS autograft of at least 9 mm in diameter between 2010 and 2021 with complete 1- and 2-year outcome scores. We compared 1- and 2-year postoperative outcome scores (visual analog scale [VAS], Knee Injury and Osteoarthritis Outcome Score [KOOS] pain, Marx Activity Rating Scale [MARS], Veterans RAND 12-Item Health Survey [VR-12]) between BPTB, QT, and HS of the same size graft. In total, 2,318 subjects were included in the analysis, and all graft types showed improved patient-reported outcome measures at 1 and 2 years postoperatively when compared with baseline. The KOOS pain score for the BPTB group was significantly better than the HS (between-group difference= 2.71, P < .01) and QT (between-group difference= 2.51, P < .01) groups at 1 year, and the BPTB group was better than HS (between-group difference= 1.88, P < .01) at 2 years. However, the differences were small and not clinically meaningful. When we compared graft type, there were no differences in the percentage of patients who reached Minimal clinically important difference, or clinical scores VAS or MARS at 2-year follow-up. There is no clinically meaningful difference in KOOS-pain, VR-12, VAS, and MARS at 1 and 2 years postoperatively in patients having anterior cruciate ligament reconstruction with BPTB, HS, or QT if graft size is at least 9 mm in diameter. Level III, retrospective comparative study.

Bridge-Enhanced Anterior Cruciate Ligament Restoration: 6-Year Results From the First-in-Human Cohort Study.

Bridge-enhanced anterior cruciate ligament restoration (BEAR) combines suture repair of the anterior cruciate ligament (ACL) with an extracellular matrix implant plus autologous blood to facilitate native ACL healing. The purpose of this study was to compare the 6-year follow-up outcomes of patients who underwent the BEAR procedure with those of a nonrandomized concurrent control group receiving autograft ACL reconstruction (ACLR) in the first-in-human safety study of the BEAR implant (BEAR I trial). Based on the 2-year results, it was hypothesized that isometric hamstring strength after the BEAR procedure would be greater than that after ACLR and that there would be no other differences in outcomes at 6 years. Cohort study, Level of evidence, 2. Ten patients underwent BEAR and 10 received ACLR with a 4-stranded hamstring autograft. Outcomes assessed included the record of subsequent surgeries, the International Knee Documentation Committee (IKDC) Subjective Knee Score, IKDC physical examination grade, the Knee injury and Osteoarthritis Outcome Score, instrumented knee laxity, functional outcomes (ie, muscle strength assessments and hop testing), and qualitative magnetic resonance imaging assessment. Comparisons between treatments were based on computations of the mean differences and the associated 95% CIs. One patient in the BEAR group and 3 patients in the ACLR group were lost to follow-up. In the period between 2 and 6 years, 1 patient in each group underwent revision surgery. There were no differences between groups at the 6-year follow-up in any of the outcome measures except for isometric hamstring strength, which was approximately equal to that of the contralateral knee in the BEAR group and <44% of that in the contralateral knee in the ACLR group (P < .01). This preliminary study suggests that the outcomes of BEAR and ACLR with a hamstring tendon graft may be similar at the 6-year follow-up and warrants investigation of the BEAR procedure in a larger cohort of patients.

Safety and Early Return to Sports for Early ACL Reconstruction in Young Athletes: A Retrospective Study.

Background and Objectives: Although previous reports have shown that early anterior cruciate ligament (ACL) reconstruction is associated with an increased risk of stiffness, recommendations for delayed surgery are based on outdated literature. The advent of arthroscopic surgery and accelerated rehabilitation protocols warrants a reexamination of the optimal surgical timing. The purpose of this study was to investigate complications during early ACL reconstruction after injury in young athletes. Materials and Methods: A total of 87 patients (27 males and 60 females) were included in this study. Patients who underwent anatomic ACL reconstruction using hamstring autografts were evaluated. Patients under 25 years of age with a Tegner activity score greater than 6 were included and classified into three groups according to the time from injury to surgical treatment: one week from injury to surgery (early group), three to six weeks from injury to surgery (normal group), and three to six months from injury to surgery (delayed group). We evaluated the rates of various complications such as graft rupture, contralateral injury, the need for manipulation for loss of ROM, infection, and fracture around the knee up to 2 years postoperatively. In addition, we investigated postoperative muscle strength, Lysholm score, Tegner activity score, and period of the return to sport from injury. Results: Patients in the delayed group were younger than those in the other groups (p = 0.009). Patients in the early group had a lower range of motion than those in the other groups preoperationly. However, the 1-month postoperative range of motion was comparable between groups. Patients in the early group had greater postoperative Tegner activity scores than those in the other groups. The period of return to sport from injury in the delayed group was longer than in the other groups. There were no statistically significant differences in the postoperative complication rate, muscle strength, or Lysholm score. Conclusions: ACL reconstruction performed 1 week from injury to surgery in young athletic patients indicated the rate of complications were not significantly different among the groups. Early ACL reconstruction with no postoperative complications may be related to early return to sports and a high level of sports.