Hamstring Anterior Cruciate Ligament Reconstruction Research Articles

Young men undergoing anterior cruciate ligament reconstruction with patellar tendon autograft and anteromedial drilling outperform at 5- to 10-year follow-up in terms of graft stability and activity levels compared to those undergoing reconstruction with hamstring autograft and transtibial drilling

ObjectiveTo compare 5- to 10-year outcomes of anterior cruciate ligament (ACL) reconstruction in young men performed with bone-patellar tendon bone (BPTB) autograft and anteromedial portal to reconstruction with hamstring autograft and transtibial technique. It was hypothesised that in young adult men, at 5- to 10-year follow-up, superior restoration of knee laxity and activity levels would be demonstrated using BPTB autograft and anteromedial portal technique. MethodsNinety-four men who had ACL reconstruction with BPTB autograft and anteromedial portal were eligible for comparison to 106 men who had reconstruction with hamstring autograft and transtibial technique. Inclusion criteria were: (1) age 18–35 years, (2) ACL tear caused by sports trauma only, (3) no concomitant ligament reconstruction and (4) 5- to 10-year follow-up. Outcome measures compared between the two groups included Lachman and pivot shift tests, KT side-to-side difference, Tegner and Marx scores, International Knee Documentation Committee (IKDC)-subjective score, Knee Osteoarthritis Outcome Scale (KOOS), Short Form (SF)-36, and single hop test for distance. P value ​< ​0.05 indicated statistical significance. ResultsForty-five patients with BPTB and 55 patients with hamstring ACL reconstruction were available for in-person assessment at 5–10 years after surgery. Outcomes in the BPTB group compared to the hamstring group showed KT difference 1.4 ​± ​1.9 mm vs. 2.8 ​± ​2.3 mm (p ​< ​0.01), pivot shift grade 2–3 in 4% vs. 34% (p ​< ​0.01), return to preinjury Tegner level in 51% vs. 36% (p ​= 0.1) and to preinjury Marx score in 29% vs. 11% (p ​= 0.02), and IKDC-subjective 88 ​± ​10 vs. 82 ​± ​13 vs (p ​< ​0.01), respectively. Statistically significant inter-relationships were found between KT side-to-side difference and the Tegner, Marx and IKDC-subjective scores at follow-up (r ​= ​−0.314, p ​< ​0.01; r ​= ​−0.263, p ​< ​0.01; r ​= ​−0.218, p ​= ​0.03, respectively). ConclusionYoung men undergoing ACL reconstruction with patellar tendon autograft and anteromedial drilling outperform at 5- to 10-year follow-up in terms of graft stability and activity levels compared to young men undergoing reconstruction with hamstring autograft and transtibial drilling. Level of EvidenceIII (Retrospective cross-sectional comparative study).

No Difference in Bone Tunnel Enlargement and Clinical Outcome between Cortical Suspension and Hybrid Femoral Fixation in Hamstring Anterior Cruciate Ligament Reconstruction.

The best method for femoral fixation in anterior cruciate ligament reconstruction (ACLR) remains controversial. The study assesses the bone tunnel enlargement and clinical outcome in hamstring ACLR using cortical suspension or hybrid (cortical suspension and compression) femoral fixation. From January 2010 to December 2021, 102 patients who underwent quadruple hamstring ACLR using cortical suspension (39 patients) or hybrid (63 patients) fixation on the femoral side were retrospectively analyzed. Clinical evaluation was conducted using the international knee documentation committee score, the Lysholm score, the Tegner activity level scale, the knee injury and osteoarthritis outcome score (quality of life score), the Lachman test, and the side-to-side difference by the KT-1000 arthrometer. The complications after the surgery were also evaluated. These data were compared at baseline and last follow-up. The diameters of the femoral tunnel were calculated at three sites: the width of the entrance of the femoral tunnel, 1 cm proximal to the entrance of the femoral tunnel and the largest diameter of the femoral tunnel on magnetic resonance imaging (MRI) coronal images. Bone tunnel widening data were contrasted between MRI images conducted at least 2 years and within 2 weeks after surgery. The morphology of bone tunnel enlargement was also observed and recorded. The categorical parameters were analyzed using the χ2-test and Fisher's exact test. The continuous variables conforming to a normal distribution were analyzed using Student's t-test, and the Mann-Whitney U-test was undertaken between the two groups without normal distribution. Both cortical suspension and hybrid femoral fixation in quadruple hamstring ACLR achieved significantly improved patient-reported outcome scores and knee stability compared to preoperative data. However, no significant differences were found between these two methods in clinical evaluations, postoperative complications, and patient-reported outcome scores. Although the mean diameter of the enlarged bone tunnel was lowered by an additional bioabsorbable interference screw fixation near the joint line, a statistically insignificant difference was found between the hybrid and cortical suspension fixation on the femoral side. There was no statistical difference in the distribution of enlarged bone tunnel morphology between groups. No significant difference was found in the bone tunnel enlargement and clinical outcome between cortical suspension and hybrid femoral fixation in ACLR using hamstring autograft.

Risk of Revision and Reoperation After Quadriceps Tendon Autograft ACL Reconstruction Compared With Patellar Tendon and Hamstring Autografts in a US Cohort of 21,973 Patients

Background: The use of quadriceps tendon (QT) autografts has increased in the past 10 years. However, there remains a dearth of large studies examining the effects of graft selection on anterior cruciate ligament reconstruction (ACLR) that includes QT grafts. Purpose: To evaluate the risk of subsequent surgical outcomes, including revision and reoperation, for a large cohort of patients with primary ACLR according to autograft selection. Study Design: Cohort study; Level of evidence, 2. Methods: Data from a US health care system ACLR registry were used to conduct a cohort study. Primary isolated autograft ACLRs were identified (2012-2021). The exposure of interest was autograft type: QT, bone–patellar tendon–bone (BPTB), and hamstring tendon (HT). Multivariable Cox regression models were used to evaluate the risk of aseptic revision (defined as a subsequent surgery where removal and replacement of the original graft for noninfectious reasons was required) and risk of aseptic reoperation (defined as any subsequent surgery for noninfectious reasons where the graft was left intact) according to autograft selection. Results: The study sample comprised 21,973 ACLRs performed by 290 surgeons at 53 hospitals. QT, BPTB, and HT autografts were used in 1103 (5.0%), 9519 (43.3%), and 11,351 (51.7%) ACLRs, respectively. In adjusted models, no significant differences were observed in revision risk (hazard ratio [HR], 1.06; 95% CI, 0.60-1.89; P = .837) or reoperation risk (HR, 1.00; 95% CI, 0.70-1.43; P = .993) within 4 years of follow-up when comparing QT ACLR with BPTB ACLR. Additionally, no differences in 4-year revision (HR, 0.62; 95% CI, 0.34-1.12; P = .111) or reoperation (HR, 1.24; 95% CI, 0.85-1.80; P = .262) risks were observed when comparing QT ACLR with HT ACLR. HT ACLRs were noted to have a higher risk of revision (HR, 1.52; 95% CI, 1.25-1.84; P < .001) compared with BPTB ACLRs but a lower risk of reoperation (HR, 0.86; 95% CI, 0.75-0.98; P = .024). Conclusion: In this large multicenter study using data from an ACLR registry, the authors found no difference in the risk of revision or reoperation when QT was compared with BPTB or HT autograft with the numbers available, but they did find a 1.5 times higher risk of revision when HT autograft was compared with BPTB autograft. Surgeons may use this information when choosing the appropriate graft for ACLR in their patients.

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

BackgroundDifferent 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).MethodsPatients 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.ResultsOf 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%.ConclusionDifferent 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 evidenceIV

A comparative analysis of suture-augmented and standard hamstring autograft single-bundle ACL reconstruction outcomes: short-term functional benefits without long-term impact

BackgroundAugmentation of the biologic graft with nonabsorbable suture material during anterior cruciate ligament reconstruction (ACLR) is a relatively new technique to enhance its biomechanical properties and add additional support to the critical process of healing. We aimed to compare the short-term functional patient-reported outcome measures (PROMs) and complication rates of patients treated with either standard single-bundle four-strand hamstring ACLR or added suture augmentation (SA).MethodsPatients undergoing arthroscopic ACLR between February 2015-January 2017 and in the standard ACLR group, and between February 2017-September 2019 in the SA-ACLR group operated by adding a no.5 FiberWire® (Arthrex, Naples, FL, USA) braided suture to the hamstring autograft, were retrospectively reviewed and the PROMs were compared. Patients were followed up for a 24-month period and PROMs were assessed by the International Knee Documentation Committee (IKDC) Subjective Knee Form and Tegner-Lysholm knee score. Patients’ demographic and clinical characteristics, and postoperative complications including graft retear requiring revision surgery, deep vein thrombois, and surgical site infection were recorded and analyzed.ResultsWe included 79 patients with mean age of 31.6 ± 8.3 years in the standard ACLR group, and 90 patients with mean oge of 30.5 ± 7.6 in the SA-ACLR group. There was no statistically significant difference between the two groups in terms of age, sex, body mass index, and medical comorbidities. The values of the IKDC scores increased to 75.8 ± 18.9 in the standard ACLR group, and 85.6 ± 12.6 in the SA-ACLR group, 24 months after the operation (P < 0.05). The 24-month postoperative Tegner-Lysholm scores escalated to 79.3 ± 21.0 in the standard ACLR group and 91.0 ± 13.7 in the SA-ACLR group (P < 0.05). Four (5.1%) patients in the standard ACLR group and 4 (4.4%) in the SA-ACLR group experienced graft retear requiring revision surgery (P > 0.05). Incidence of surgical site infection and deep vein thrombosis showed no significant differences between the two groups, 24 months after ACLR.ConclusionSA-ACLR is associated with improved short-term functional PROMs compared to the standard hamstring ACLR. Although SA did not reduce the retear rate, and infection and DVT rates did not differ between study groups, superior improvement of PROMs in SA approach, leverages this method for ACLR.

Stand-Alone Tibial Interference Screw Fixation and Tibial Interference Screw Plus Tibial Staple Fixation Produce Comparable Outcomes After Primary Anterior Cruciate Ligament Reconstruction Using Hamstring Autografts

To investigate the impact of adding a metal staple alongside the interference screw in tibial side graft fixation during anterior cruciate ligament reconstruction (ACLR). All patients treated with autograft hamstring ACLR at our institution between January 2017 and December 2021 with a minimum 1-year follow-up were reviewed retrospectively. Patients treated with a stand-alone interference screw for tibial side fixation were compared with those treated with a combination of interference screw and staple. The primary outcome was failure of the reconstructed graft. Secondary outcomes were operative time, complication rate, and reoperation rate. A total of 497 patients met the study's inclusion and exclusion criteria. A combination of staple and interference screw was used in 167 patients (33.6%), whereas a standalone interference screw was used in 330 patients. There was no significant difference between the 2 groups in terms of operative time, complication rate, or failure rate. The mean follow-up was 23.25 (±13.29) months. Our results demonstrate that augmenting the interference screw with a staple for tibial-side fixation in ACLR does not have a significant impact on operative time, reoperation rate, complications, or failure rates. Level III, retrospective cohort study.

Recurrent Instability Rate and Subjective Knee Function following Accelerated Rehabilitation after ACL Reconstruction in Comparison to a Conservative Rehabilitation Protocol.

The Purpose of the present study was to assess the outcome of anterior cruciate ligament reconstruction (ACLR) with an accelerated rehabilitation protocol and to compare it to a conservative rehabilitation protocol. It was hypothesized that an accelerated rehabilitation protocol, including brace-free early weight bearing, would result in a higher rate of recurrent instability and revision surgery compared to a conservative rehabilitation protocol. From 2016 to 2017, two different rehabilitation protocols for isolated ACLR were used at a high-volume knee surgery center. A total of 65 consecutive patients with isolated hamstring ACLR, of whom n = 33 had been treated with an accelerated (AccRehab) and n = 32 with a conservative rehabilitation protocol (ConRehab), were retrospectively included in the study. Patients were evaluated for recurrent instability, revision surgery, and other complications at a mean follow-up period of 64 ± 7.4 months. In addition, Tegner Activity Scale, Lysholm Score, and IKDC-subjective Score were evaluated. Statistical comparison between the two groups was performed utilizing Fisher's exact test and Student's t-test. Mean age (29.3 vs. 26.6 years) and preoperative Tegner Score (6.4 vs. 5.9) were comparable between both groups. At 64 ± 7.4 months after ACLR, six cases of recurrent instability were reported in the AccRehab group (18%) in comparison to three cases (9%) in the ConRehab group (p = n.s.). There was no significant difference regarding revision surgery and further complications. Furthermore, no significant difference was found between both groups regarding Tegner (5.5 ± 1.9 vs. 5.5 ± 1.2), Lysholm (93.6 ± 6.3 vs. 89.3 ± 10.7), and IKDC score (89.7 ± 7.9 vs. 86.7 ± 12.1). No significant disadvantage of an accelerated rehabilitation protocol following ACLR was found in terms of recurrent instability rate, revision surgery, or patient-reported outcome. However, a trend towards a higher reinstability rate was found for an accelerated rehabilitation protocol. Future level one trials evaluating brace-free early weight bearing following ACLR are desirable.

Poster 332: Return to Sport, Post-Operative Performance Testing, and Re-injury Rates Among Athletes Treated with Hamstring, Quadriceps, and Patellar Tendon Autograft ACL Reconstruction

Objectives: Anterior Cruciate Ligament (ACL) tears are a common sporting injury and optimal graft choice is of concern for both patients and surgeons. Few comparative studies have evaluated return to sport and reinjury rates across graft types. The purpose of the present study was to evaluate return to sport rates and reinjuries among hamstring tendon (HT), quadriceps tendon (QT), and patellar tendon (BPTB) ACL reconstructions. Methods: Recreational and competitive athletes ages 13-24 from 2010-2022 that underwent primary or revision ACL reconstruction were included. There were 837 total athletes comprised of 341 HT, 358 BPTB, and 138 QT autografts, of which 729 were primary and 108 were revision surgeries. Return to sport (RTS) rates, RTS testing results, clearance time, and reinjury rates were collected. RTS testing data included isokinetic testing of quadricep and hamstring strength and functional movement screening. A Kruskal-Wallis test was used to detect differences among continuous variables. A GLIMMIX procedure was completed for multivariate analysis to detect differences between groups after adjusting for age and activity level. Chi-square statistics and Fisher’s exact test were used for categorical variables. Odds ratio, adjusted odds ratio, and 95% confidence intervals were provided by logistic regression. All statistical analyses were performed using SAS 9.4 (Cary, NC). Statistical significance was measured at p&lt;0.05. Results: The median ages were 18 for HT and BPTB and 17 for QT (p= 0.0001). Females comprised 50.73% of HT grafts, 42.86% of BPTB grafts, and 41.30% of QT grafts. Return to previous level of play was observed in 118/130 (90.77%) HT, 124/136 (91.18%) BPTB, and 39/52 (75.00%) of QT grafts (p=0.0045); BPTB remained statistically more likely to return to previous level of play than QT after adjusting for age and activity level. RTS testing was completed in 28/341 (8.21%) HT, 142/358 (39.66%) BPTB, and 80/138 (57.97%) QT grafts (p&lt;0.001); after adjusting for age and activity level, the results remained significant. Median isokinetic quadriceps testing at 300 degrees per second was 92% for 26 HT athletes, 83% for 134 BPTB athletes, and 87% for 77 QT athletes (p= 0.0006); results remained significant following age and activity level adjustment. Median isokinetic hamstring testing at 60 degrees per second was 89% for 24 HT athletes, 101% for 135 BPTB athletes, and 100% for 79 QT athletes (p=0.0007); results remained significant after adjustment for age and activity level. The median single- leg hop ratio was 98% for 5 HT athletes, 85% for 12 BPTB athletes, and 96% for 14 QT athletes (p=0.044); after adjusting for age and activity level, results remained significant. Time to be cleared for RTS was 25.89 weeks for 179 HT athletes, 34.75 weeks for 186 BPTB athletes, and 35.74 weeks for 75 QT athletes (p &lt;0.0001) with the results remaining statistically significant following adjustment for age and activity level. ACL retear rates were 12.02% for HT, 3.07% for BPTB, and 5.07% for QT (p&lt;0.0001) with hamstring grafts remaining significantly more likely to suffer an ACL retear than BPTB grafts after adjusting for age and activity level. Conclusions: After adjusting for age and activity level, BPTB ACL autografts demonstrated a lower reinjury risk when compared to HT autografts. When comparing QT and BPTB, return to sport testing 6-9 months post-op was superior in the QT group; however, BPTB patients were more likely to return to sport. This data can help influence surgeon and patient shared decision-making models in athletes with ACL injuries.

Paper 31: Quantitative MRI of the Hamstring Muscles Ten Years After Autograft Hamstring ACLR

Paper 31: Quantitative MRI of the Hamstring Muscles Ten Years After Autograft Hamstring ACLR

Suture Augmentation of a Four-Strand Semitendinosus Graft Improves Time-Zero Biomechanical Properties

To compare the time-zero biomechanical properties of hamstring graft preparations with or without suture augmentation for anterior cruciate ligament reconstruction (ACLR) in a full-construct cadaveric model. Hamstring grafts were harvested from 24 fresh frozen human cadavers and prepared in 1 of 3 ways: quadrupled SemiTendinosus (SemiT), and quadrupled SemiT with suture augmentation (SemiT+2.0-mm tape or SemiT+1.3-mm tape; n= 8 per group). Adjustable loop suspensory implants and cortical buttons were used for fixation on a porcine tibia and acrylic block. Testing included force-controlled cyclic loading at 250 N and 400 N followed by load to failure. The 2 suture augmentation groups had less total elongation and increased stiffness compared to the nonsuture-augmented group (P= .025). The SemiT+2.0-mm tape group had 36% less total elongation and 34% increased stiffness compared to SemiT+1.3mm tape (P < .001). Suture augmentation improves construct biomechanics at time zero following hamstring tendon ACLR. Augmentation with 2.0-mm tape suture improves construct biomechanics compared to 1.3-mm tape suture. Independent suture augmentation of a quadrupled SemiT graft improves ACLR construct biomechanics. Outcomes were improved with augmentation using 2.0-mm tape suture compared to 1.3-mm tape suture.

Osteoconductive Scaffold Placed at the Femoral Tunnel Aperture in Hamstring Tendon ACL Reconstruction: A Randomized Controlled Trial.

Bone tunnel enlargement after single-bundle anterior cruciate ligament reconstruction remains an unsolved problem that complicates revision surgery. Positioning of an osteoconductive scaffold at the femoral tunnel aperture improves graft-to-bone incorporation and thereby decreases bone tunnel widening. Randomized controlled trial; Level of evidence, 1. In a 1:1 ratio, 56 patients undergoing primary anterior cruciate ligament reconstruction were randomized to receive femoral fixation with cortical suspension fixation and secondary press-fit fixation at the tunnel aperture of the tendon graft only (control) or with augmentation by an osteoconductive scaffold (intervention). Adverse events, patient-reported outcomes, and passive knee stability were recorded over 2 years after the index surgery. Three-dimensional bone tunnel widening was assessed using computed tomography at the time of surgery and 4.5 months and 1 year postoperatively. The intervention group exhibited a similar number of adverse events as the control group (8 vs 10; P = .775) including 2 partial reruptures in both groups. The approach was feasible, although 1 case was encountered where the osteoconductive scaffold was malpositioned without adversely affecting the patient's recovery. There was no difference between the intervention and control groups in femoral bone tunnel enlargement, as expressed by the relative change in tunnel volume from surgery to 4.5 months (mean ± SD, 36% ± 25% vs 40% ± 25%; P = .644) and 1 year (19% ± 20% vs 17% ± 25%; P =.698). Press-fit graft fixation with an osteoconductive scaffold positioned at the femoral tunnel aperture is safe but does not decrease femoral bone tunnel enlargement at postoperative 1 year. NCT03462823 (ClinicalTrials.gov identifier).

What's New in Sports Medicine.

What's New in Sports Medicine.

The Effect of Tibial Tunnel Drilling Technique on Retained Intra-Articular Bone Debris Following Anterior Cruciate Ligament Reconstruction

To assess the effect of tibial tunnel drilling technique (retro-drilled bone socket vs full tibial tunnel) on the presence and grade of postoperative, intra-articular bone debris following primary hamstring anterior cruciate ligament (ACL) reconstruction. This was a retrospective cohort study of primary hamstring autograft ACL reconstructions performed by 2 surgeons. Two blinded independent reviewers assessed the presence and length of retained intra-articular bone debris on the immediate postoperative lateral radiograph. Debris was graded according to a predefined 5-point ordinal grading system: grade 0 (no debris) to IV (severe debris). Results were analyzed according to the type of tibial tunnel; retro-drilled socket or full tibial tunnel using Kappa statistics and the Mann-Whitney U test. Sixty-five patients undergoing primary hamstring ACL were included (39 tibial socket: 26 full tibial tunnel). Bone debris was observed among the tibial socket technique in 29 of 39 instances (74.3%), compared with 14 of 26 (53.8%) instances for the full tibial tunnel technique (P= .09). Where there was measurable debris present, the tibial socket group had a mean length of bone debris of 13.7 ± 6.2 mm as compared with the full tibial tunnel, 10.0 ± 4.7 mm (P= .165). There were significant differences in bonedebris gradings between the 2 treatment groups, with tibial sockets having an overall greater grade (P= .04). A difference in the presence of, or length of, retained bone debris on the postoperative lateral radiograph was not demonstrated between the retro-drilled bone socket and full tibial tunnel techniques. However, when bone debris was present, greater grades of debris were seen in the retro-drilled socket group. III, retrospective, comparative study.

THE DOSTAR STUDY: A DOUBLE-BLINDED, RANDOMIZED CONTROLLED TRIAL COMPARING DUAL OR SINGLE HAMSTRING TENDON ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

Hamstring grafts have been associated with reduced strength, donor site pain and muscle strains following Anterior Cruciate Ligament Reconstruction (ACLR). Traditional graft fixation methods required both semitendinosus and gracilis tendons to achieve a graft of sufficient length and diameter, but newer techniques allow for shorter, broad single tendon grafts.This study seeks to compare the outcomes between Single Tendon (ST) and Dual Tendon (DT) ACLR, given there is no prospective randomised controlled trial (RCT) in the literature comparing outcomes between these options.In this ongoing RCT: (ANZ Clinical Trials Registry ACTRN126200000927921) patients were recruited and randomised into either ST or DT groups. All anaesthetic and surgical techniques were uniform aside from graft technique and tibial fixation. 13 patients were excluded at surgery as their ST graft did not achieve a minimum 8mm diameter. 70 patients (34 ST, 36DT) have been assessed at 6 months, using PROMS including IKDC2000, Lysholm and Modified Cincinnati Knee, visual analog scale for pain frequency (VAS-F) and severity (VAS-S), dedicated donor site morbidity score, KT-1000 assessment, and isokinetic strength.Graft diameters were significantly lesser in the ST group compared to the DT group (8.44mm/9.11mm mean difference [MD],-0.67mm; P&lt;0.001). There was a significant and moderate effect in lower donor site morbidity in the ST group compared to the DT group (effect size [ES], 0.649; P = .01). No differences between groups were observed for knee laxity in the ACLR limb (P=0.362) or any of the patient-reported outcome measures (P&gt;0.05). Between-group differences were observed for hamstrings strength LSI favouring the ST group, though these were small-to-moderate and non-significant (ES, 0.351; P = .147).ST (versus DT) harvest results in significantly less donor site morbidity and this is the first prospective RCT to determine this. There were no differences between ST and DT hamstring ACLR were observed in PROMs, knee laxity and hamstring strength. Younger female patients tend to have inadequate single tendon size to produce a graft of sufficient diameter, and alternative techniques should be considered. Further endpoints include radiological analysis, longer term donor site morbidity, revision rates and return to sport and will continue to be presented in the future.

Interference screws 3D printed with polymer-based biocomposites (HA/PLA/PCL)

ABSTRACT Anterior cruciate ligament (ACL) reconstruction frequently employs the bioabsorbable interference screw, which is 3D printed with biocomposite filaments. The purpose of this research was to construct interference screws using 3D printing filaments (HA, PLA, and PCL) at different nozzle temperatures. In this experiment, nozzle temperatures of 190, 195, 200, and 205°C were used. Density tests, torsion tests, fracture analysis, and biodegradable tests were also used to characterize interference screws. A simple finite element model (FEM) of tibial screw fixation in hamstring ACL reconstruction was also presented. The interference screw was also compared to a commercial one. Within the maximum and minimum values of cortical bone density, the density of the interference screw prepared in this study is the best fit for implants. The current model can predict stress in tunnel wall regions caused by screw fixation. However, the clamping quality of the commercial screw in the clamping failure area for torque efficiency was better than that of the interference screw produced in this study. Commercial interference screws deteriorated the most quickly. The method has shown the ability to manufacture interference screw components with improved biodegradability.

Comparable rates of secondary surgery between anterior cruciate ligament repair with suture tape augmentation and anterior cruciate ligament reconstruction

PurposeThe aim of this study was to determine the frequency of secondary surgery following anterior cruciate ligament (ACL) repair with suture tape augmentation in comparison to conventional hamstring ACL reconstruction. We hypothesised that there would be no differences between the groups.MethodsThis was a retrospective comparison study of patients undergoing ACL surgery between September 2011 and April 2018. Two hundred and 73 patients underwent ACL reconstruction using hamstring autograft. During the same timeframe, 137 patients with an acute proximal ACL rupture underwent ACL repair with suture tape augmentation. One patient was lost to follow-up in the ACL reconstruction group leaving 272 patients (99.6%) for the final analysis. In the ACL repair group, three patients were lost to follow-up leaving 134 patents (97.8%) for the final analysis. Secondary surgery was identified by contacting the patients by email/telephone and reviewing patient notes at the time of this analysis.ResultsRe-rupture occurred in 32 patients (11.8%) in the ACL reconstruction group compared to 22 patients (16.4%) in the ACL repair group (p = 0.194). Contralateral ACL rupture occurred in four patients (1.5%) in the ACL reconstruction group compared to three patients (2.2%) in the ACL repair group (p = 0.224). In the ACL reconstruction group, nine patients (3.3%) required secondary meniscal surgery whilst five patients (3.7%) required meniscal surgery in the ACL repair group (p = 0.830). Seven other operations were performed in the ACL reconstruction group (2.6%) compared to three other operations in the ACL repair group (2.2%) (p = 0.374). The overall number of patients undergoing secondary surgery in the ACL reconstruction group was 52 (19.1%) in comparison to 30 (22.4%) in the ACL repair group (p = 0.114).ConclusionACL repair with suture tape augmentation for acute proximal ruptures demonstrated comparable rates of secondary surgery with hamstring ACL reconstruction.

Clinical and arthroscopic outcomes of single-bundle anterior cruciate ligament reconstruction using autologous hamstrings augmented with ligament augmentation and reconstruction systems compared with four-strand hamstring tendon grafts alone.

To compare the clinical, radiological, and second-look arthroscopic outcomes in patients who underwent anterior cruciate ligament (ACL) reconstruction using a four-strand hamstring tendon graft (hamstring group) either without augmentation or with ligament augmentation and reconstruction system (LARS) augmentation (LARS augmentation group). From January 2018 to December 2019, patients who underwent ACL reconstruction were included. Patient-reported outcome measures (PROMs) were undertaken pre-operatively and at three, six, 12, and 24months post-operatively. Arthroscopic evaluation was performed focusing on the morphology of the graft based on graft tension, graft tear, and synovial coverage. A total of 178 consecutive patients received single-bundle ACL reconstruction, 89 patients in each group, and 20 patients were lost to follow-up in the first twoyears. At the threemonth follow-up, the LARS augmentation group had significantly higher Lysholm scores, IKDC scores, and KOS-ADLS scores than the hamstring group (P < 0.001). At the three, six and 12-month follow-ups, there were significantly higher Tegner scores and ACL-RSI scores in the LARS augmentation group than in the hamstring group (P < 0.05). At the three and sixmonth follow-ups, the LARS augmentation group had significantly higher rates of return to sports and return to sports at their preinjury level (P < 0.05). There were no between-group differences in other outcomes, including arthroscopic outcomes, graft signal intensity, post-operative complications or rerupture rates. Autologous hamstring augmented with the LARS augmentation technique provides good and realistic clinical and functional results during the early post-operative period with high levels of satisfaction of patients, including participation in sports and physical activity, and high rates of return to sports at the preinjury level, without any apparent complications compared with hamstring ACL reconstruction alone. No increases in complication, reinjury rates, or increased lateral laxity were observed at the 12-month or 24-month follow-up.

General, spinal or regional anaesthesia does not affect strength performance 6 months after ACL reconstruction

PurposeThe recovery of strength is a key element in successfully returning to sports after ACL reconstruction. The type of anaesthesia has been suspected an influential factor in the post-operative recovery of muscle function.MethodsIn this retrospective analysis, n = 442 consecutive patients undergoing primary isolated ACL reconstruction using a hamstring autograft were analysed by pre- and post-operative isokinetic tests in a single orthopaedic centre. These were subdivided into four cohorts: (1) general anaesthesia (n = 47), (2) general anaesthesia with prolonged (48 h) on-demand femoral nerve block (n = 37), (3) spinal anaesthesia (n = 169) and (4) spinal anaesthesia with prolonged (48 h) on-demand femoral nerve block (n = 185). Primary outcome was the change from pre- to post-operative isokinetic strength during knee extension and flexion.ResultsUsing one-way ANOVA, there was no significant influence of the type of anaesthesia. The main effect of anaesthesia on change in extension forces was not significant, and effect sizes were very small (n.s.). Similarly, the main effect of anaesthesia on change in flexion forces was statistically not significant (n.s.).ConclusionsThe findings of this study support the interpretation that the type of anaesthesia has no significant effect on the ability to recover thigh muscle strength 6 months after isolated hamstring ACL reconstruction. With regard to the recovery of athletic performance and return-to-sports testing criteria, there is no reason to avoid regional anaesthesia.Level of evidenceIII.

Anterior Cruciate Ligament Reconstruction with 4-Strand Hamstring Tendon Construct May be Biomechanically Superior to 5-Strand Hamstring Tendon Construct When Using Femoral Suspensory Fixation

PurposeTo compare stiffness, strain, and load to failure of 4- versus 5-strand hamstring anterior cruciate ligament reconstruction human tendon allografts with femoral suspensory and tibial interference screw fixationMethodsAllograft hamstring tendons were used to create 10 four-strand (4S) and 10 five-strand (5S) grafts. Grafts were fixed to a uniaxial electromechanical load system via a femoral cortical suspensory button and a bioabsorbable interference screw in bone analogue. Grafts were cycled from 100 Newtons (N) to 250 N for 1,000 repetitions at 0.5 hertz before load to failure testing. Cyclic displacement was defined as the difference in graft length from the first 20 to 30 cycles compared with the last 10 cycles. Trials were recorded on a high-definition camera to allow for digital image correlation analysis.ResultsCyclic displacement more than 1,000 cycles was significantly lower in the 4S compared with the 5S group (0.87 vs 1.11 mm, P = .037). Digital image correlation analysis confirmed that the fifth strand elongated more than the other 4 strands in the 5S constructs (6.1% vs 3.9%, P = .032). Load to failure was greater in the 4S compared with the 5S group but not statistically significant (762 vs 707 N, P = .35). Stiffness was similar between constructs (138.5 vs 138.3 N/mm, P = .96)ConclusionsCompared with cyclically loaded 4S hamstring grafts, the 5S grafts had significantly increased displacement over time in a model of femoral suspensory and tibial interference screw fixation.Clinical RelevanceAnterior cruciate ligament reconstruction with hamstring tendon autograft is a commonly performed surgery with excellent outcomes. It has been shown that graft diameter influences these outcomes. As surgeons use larger grafts, it is important to investigate how these constructs may affect the outcomes of surgery.

Meniscal repair at the time of primary ACLR does not negatively influence short term knee stability, graft rupture rates, or patient-reported outcome measures: the STABILITY experience.

To assess how meniscal repair and excision impact short term patient-reported outcome measures (PROMs), knee stability, and early graft rupture rates following primary hamstring anterior cruciate ligament reconstruction (ACLR) with or without lateral extra-articular tenodesis (LET) in a group of young active patients where meniscal repair is commonly advocated. Six hundred and eighteen patients under 25years of age at high-risk of graft failure following ACLR were recruited to the Stability 1 study. Multivariable regression models were developed to identify statistically and clinically significant surgical and demographic predictors of Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee Subjective Knee Form (IKDC), ACL Quality of Life Questionnaire (ACL-QOL) and Marx Activity Rating Scale (MARS) scores. Chi-Square tests of independence were used to explore the association between meniscal status (torn, not torn), meniscal treatment (excision or repair), graft rupture, and rotatory knee laxity. Medial meniscus repair was associated with worse outcomes on the KOOS (β = -1.32, 95% CI: -1.57 to -1.10, p = 0.003), IKDC (β = -1.66, 95% CI: -1.53 to -1.02, p = 0.031) and ACL-QOL (β = -1.25, 95% CI: -1.61 to 1.02, p = n.s.). However, these associations indicated small, clinically insignificant changes based on reported measures of clinical relevance. Other important predictors of post-operative PROMs included age, sex, and baseline scores. Medial meniscus excision and lateral meniscus treatment (repair or excision) did not have an important influence on PROMs. There was no significant association between meniscal treatment and graft rupture or rotatory knee laxity. While repairing the medial meniscus may result in a small reduction in PROM scores at two-year follow-up, these differences are not likely to be important to patients or clinicians. Any surgical morbidity associated with meniscal repair appears negligible in terms of PROMs. Meniscal repair does not affect rotatory laxity or graft failure rates in the short term. Therefore, meniscal repair should likely be maintained as the standard of care for concomitant meniscal tears with ACLR. III.