Quadriceps Tendon Versus Hamstring Tendon Autografts for Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

Peroneus longus tendon autograft versus allograft in revision ACLR: A retrospective comparison

PURPOSE

The use of peroneus longus tendon (PLT) autografts in primary anterior cruciate ligament reconstruction (ACLR) has increased recently, but there is a lack of research on its use in revision ACLR. This study aimed to compare the clinical outcomes and complications between revision ACLR using allografts and PLT autografts.

MATERIALS AND METHODS

Fifty-nine patients who underwent arthroscopic revision of ACLR with complete clinical follow-ups between 2012 and 2021 were retrospectively reviewed. Allograft was used in 44 of these patients, and PLT autograft was used in 15 of them. Lysholm knee score, Tegner activity score, Lachman, and anterior drawer tests were performed after a mean follow-up of 60months (range: 19-116). The American Orthopaedic Foot and Ankle Society (AOFAS) scale was used to evaluate the donor ankle functions. Clinical outcomes and complications were compared between groups.

RESULTS

Both groups showed significantly improved functional outcomes compared to their preoperative assessments. However, both groups had similar clinical results at the final follow-up, including Lysholm knee score, Tegner activity scale, knee range of motion, return to sports, time to return to daily activities, and rate of re-rupture. No major complications were seen in any of the patients. The AOFAS score was 99.13±2.64 in the PLT autograft group without loss of ankle muscle strength, deformity, instability, and permanent iatrogenic neurovascular injuries. The cumulative cost of the allograft group was significantly higher than the PLT autograft group.

CONCLUSIONS

The PLT autograft might be an alternative autograft option to allografts due to similar clinical outcomes, low donor site morbidity, and reduced cost in ACLR revisions, especially if the primary ACLR was performed using grafts harvested around the knee.

LEVEL OF EVIDENCE

III; retrospective comparative study.

Anterior cruciate ligament reconstruction: effect of graft type and gender on early to mid-term clinical outcomes

INTRODUCTION

Anterior cruciate ligament (ACL) rupture is a debilitating condition and often requires surgery to restore joint stability. Common autografts used for reconstruction include patella tendon and hamstring tendons. The primary aim of this study was to evaluate the early to mid-term clinical outcomes of ACL reconstruction using validated patient-reported outcome measures (PROMs). The secondary aim was to compare clinical outcomes between patella tendon and hamstring tendon autografts. The tertiary aim was to compare clinical outcomes between males and females.

METHODS

Patients with an ACL rupture were evaluated before and after surgery using PROM scores which included Lysholm, Tegner, International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS), Short Form-12 Item (SF-12) and EQ-5D-5L.

RESULTS

A total of 87 patients were included in the study. All PROM scores significantly improved following surgery (p < 0.001) at a mean follow-up time of 28 months (range 12 to 88 months). The patella tendon subgroup (n = 27) had superior post-operative results as compared to the hamstring tendon subgroup (n = 60) for KOOS sport and recreation (p = 0.005), KOOS quality of life (p = 0.025), KOOS overall (p = 0.026), Tegner (p = 0.046) and IKDC (p = 0.021) scores. There was no significant difference of PROM scores between males (n = 60) and females (n = 27) (p > 0.05).

CONCLUSIONS

ACL reconstruction significantly improves clinical outcomes for patients with symptomatic instability consequent to ACL rupture. Overall, patella tendon autograft resulted in better clinical outcomes as compared to hamstring tendon autograft following surgery. Gender did not influence clinical outcome following ACL reconstruction.

Outcomes from different aspects indicate the all-inside technique may serve as an ideal option for anterior cruciate ligament reconstruction

PURPOSE

To evaluate the postoperative outcomes of the all-inside technique in arthroscopic anterior cruciate ligament reconstruction (ACLR).

METHODS

Patients who underwent ACLR using the all-inside technique between 2018 and 2021 were retrospectively assessed. All patients were followed up for at least 2 years. Functional recovery and pain relief were assessed using the International Knee Documentation Committee (IKDC) score, Lysholm score, Knee Injury and Osteoarthritis Outcome Score (KOOS) and visual analogue scale (VAS). Instrumented laxity was assessed via side-to-side difference using the Kneelax3 arthrometer. Graft maturity was estimated using the signal-to-noise quotient value based on magnetic resonance imaging (MRI). Adverse events during and after the surgery were recorded.

RESULTS

A total of 78 patients were included in this study, with a mean age of 28.1 ± 7.6 years. The IKDC (p < 0.001), Lysholm (p < 0.001) and KOOS (p < 0.001 for all subgroups) scores at the final follow-up were significantly higher than those before the surgery. The VAS scores (p < 0.05) were significantly lower than those before surgery. The side-to-side difference results indicated that 50 patients had a difference of less than 3 mm, indicating a tight graft, whereas only 1 patient had a difference of >5 mm, indicating a loose graft. The median signal-to-noise quotient of the graft on MRI was 1.4 (P25, P75: 1.0, 2.0). No intraoperative adverse events were observed. Postoperative adverse events included three cases of infection, three cases of graft rerupture, two cases of cyclops lesion and one case of surgical intervention for a meniscal tear.

CONCLUSION

ACLR using the all-inside technique offers promising results in patients with ACL rupture.

LEVEL OF EVIDENCE

Level IV.

Anterior cruciate ligament injuries in elite ski jumping reliably allow return to competition but severely affect future top performance

PURPOSE

In recent years, anterior cruciate ligament (ACL) injuries have been frequently observed in ski jumping. However, available data in this discipline are very scarce. Therefore, the purpose of this study was to investigate whether an ACL injury in elite-level ski jumping limits the performance level after ACL reconstruction (ACLR).

METHODS

Both male and female elite-level ski jumpers from five national A-teams who suffered an ACL injury were identified retrospectively by searching available media reports and Fédération Internationale de Ski (FIS) database. World Cup (WC) results and time-out-of-competition before ACL injury and after ACLR were compared. Only athletes who suffered the injury during or after the 2009-2010 season and who participated in at least one WC competition before the injury were included in this study. The level of athletes' performance from two full seasons before until three seasons after the injury was compared.

RESULTS

Eighteen elite-level ski jumpers (11 males/seven females) were eligible for the study. All male and four female athletes returned to professional competition after ACLR. One female athlete ended her career due to prolonged recovery and two have not yet recovered due to a recent injury. The mean return-to-competition (RTC) time was 14.6 months in males and 13.5 months in females. The mean WC placement decreased after the ACL injury: two seasons before injury the mean position was 17.9 ± 11.0 (n = 12), one season before it was 22.4 ± 12.8 (n = 15). After recovery, the mean placement in seasons 1-3 was: 26.4 ± 8.9 (n = 7), 25.7 ± 10.3 (n = 13), 33.6 ± 12.2 (n = 10) (p = 0.008). Among the athletes returning to competition, only six males and three females reached their preinjury level and only one male and one female (compared to seven males and three females preinjury) reached an individual top-3 placement after ACLR, accounting for less than 10% of podiums compared to preinjury.

CONCLUSION

Only 60% of the professional ski jumpers reached the preinjury level and less than 15% reached a top-3 placement after the ACL injury. These results support the fact that ACL tear during a ski jumping career may be a significant factor limiting high-level performance. In terms of clinical relevance, the findings implicate the need to analyse the reasons of these very low rates of return to elite-level performance, to analyse ACL injury and RTC rates at lower levels of performance and to develop specific prevention strategies in order to reduce the number of ACL injuries in this sport.

LEVEL OF EVIDENCE

Level IV.

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.

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.

Evaluating the quality of systematic reviews of comparative studies in autograft-based anterior cruciate ligament reconstruction using the AMSTAR-2 tool: A systematic umbrella review

PURPOSE

There remains a lack of consensus around autograft selection in anterior cruciate ligament reconstruction (ACLR), though there is a large body of overlapping systematic reviews and meta-analyses. Systematic reviews and their methodological quality were aimed to be further assessed, using a validated tool known as assessing the methodological quality of systematic reviews (AMSTAR-2).

METHODS

MEDLINE, Embase and CENTRAL were searched from inception to 23 April 2023 for systematic reviews (with/without meta-analysis) comparing primary ACLR autografts. A final quality rating from AMSTAR-2 was provided for each study ('critically low', 'low', 'moderate' or 'high' quality). Correlational analyses were conducted for ratings in relation to study characteristics.

RESULTS

Two thousand five hundred and ninety-eight studies were screened, and 50 studies were ultimately included. Twenty-four studies (48%) were rated as 'critically low', 17 (34%) as 'low', seven (14%) as 'moderate' and two (4%) as 'high' quality. The least followed domains were reporting on sources of funding (1/50 studies), the impact of risk of bias on results of meta-analyses (11/36 studies) and publication bias (17/36 studies). There was a significant increase in the frequency of studies graded as 'moderate' compared to 'low' or 'critically low' quality over time (p = 0.020).

CONCLUSION

The methodological quality of systematic reviews comparing autografts in ACLR is low, with many studies being rated lower due to commonly absent aspects of systematic review methodology such as investigating sources of funding and publication bias. More recent studies were generally more likely to be of higher quality. Authors are advised to consult AMSTAR-2 prior to conducting systematic reviews in ACLR.

LEVEL OF EVIDENCE

Level IV.

A Prospective Randomized Controlled Trial Investigating Quadriceps Versus Hamstring Tendon Autograft in Anterior Cruciate Ligament Reconstruction

BACKGROUND

Numerous graft options are available when undertaking anterior cruciate ligament (ACL) reconstruction (ACLR), although a lack of high-quality evidence exists comparing quadriceps (QT) and hamstring (HT) autografts.

PURPOSE

To investigate patient outcomes in patients undergoing HT versus QT ACLR.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

After recruitment and randomization, 112 patients (HT = 55; QT = 57) underwent ACLR. Patients were assessed pre- and postoperatively (6 weeks and 3, 6, 12, and 24 months), with a range of patient-reported outcome measures (PROMs), graft laxity (KT-1000 arthrometer; primary outcome variable), active knee flexion and extension range of motion (ROM), peak isokinetic knee extensor and flexor strength, and a 6-hop performance battery. Limb symmetry indices (LSIs) were calculated for strength and hop measures. Secondary procedures, ACL retears, and contralateral ACL tears were reported.

RESULTS

All PROMs and knee ROM measures significantly improved (P < .0001), and no other group differences (P > .05) were observed-apart from the Anterior Cruciate Ligament Return to Sport after Injury (ACL-RSI) score, which was significantly better in the HT group at 3 (P = .008), 6 (P = .010), and 12 (P = .014) months. No significant changes were observed in side-to-side laxity from 6 to 24 months (P = .105), and no group differences were observed (P = .487) at 6 (HT mean, 1.2; QT mean, 1.3), 12 (HT mean, 1.1; QT mean, 1.3), and 24 (HT mean, 1.1; QT mean, 1.2) months. While the HT group demonstrated significantly greater (P < .05) quadriceps strength LSIs at 6 and 12 months, the QT group showed significantly greater (P < .05) hamstring strength LSIs at 6, 12, and 24 months. The HT group showed significantly greater (P < .05) LSIs for the single horizontal (6 months), lateral (6 and 12 months), and medial (6 months) hop tests for distance. Up until 24 months, 1 patient (QT at 22 months) had a retear, with 2 contralateral ACL tears (QT at 19 months; HT at 23 months). Secondary procedures included 5 in the HT group (manipulation under anesthesia, notch debridement, meniscal repair, and knee arthroscopy for scar tissue) and 6 in the QT group (notch debridement, meniscal repair, knee arthroscopy for scar tissue, tibial tubercle transfer, and osteochondral autologous transplantation).

CONCLUSION

Apart from the ACL-RSI, the 2 autograft groups compared well for PROMs, knee ROM, and laxity. However, greater hamstring strength LSIs were observed for the QT cohort, with greater quadriceps strength (and hop test) LSIs in the HT cohort. The longer-term review will continue to evaluate return to sports and later-stage reinjury between the 2 graft constructs.

REGISTRATION

ACTRN12618001520224p (Australian New Zealand Clinical Trials Registry).

Strength symmetry after autograft anterior cruciate ligament reconstruction

OBJECTIVE

To compare postoperative isometric quadriceps strength indices (QI%) and hamstring strength limb symmetry indices (HI%) between partial thickness quadriceps tendon (pQT), full thickness quadriceps tendon (fQT), and bone-patellar-tendon bone (BPTB) autograft anterior cruciate ligament reconstruction (ACLR).

METHODS

Patients with primary ACLR with pQT, fQT, or BPTB autograft with the documentation of quantitative postoperative strength assessments between 2016 and 2021 were included. Isometric Biodex data, including QI% and HI% (calculated as the percentage of involved to uninvolved limb strength) were collected between 5 and 8 months and between 9 and 15 months postoperatively.

RESULTS

In total, 124 and 51 patients had 5-8- and 9-15-month follow-up strength data, respectively. No significant difference was detected between groups for sex. However, patients undergoing fQT were found to be older than those undergoing BPTB (24.6±7 vs 20.2±5; ​p = 0.01). There were no significant differences in the number of concomitant meniscus repairs between the groups (pQT vs. fQT vs. BPTB). No significant differences were detected in median (min-max) QI% between pQT, fQT, and BPTB 5-8 months [87 ​% (44%-130 ​%), 84 ​% (44%-110 ​%), 82 ​% (37%-110 ​%) or 9-15 months [89 ​% (50%-110 ​%), 89 ​% (67%-110 ​%), and 90 ​% (74%-140 ​%)] postoperatively. Similarly, no differences were detected in median HI% between the groups 5-8 months or 9-15 months postoperatively.

CONCLUSION

The study was unable to detect differences in the recovery of quadriceps strength between patients undergoing ACLR with pQT, fQT, and BPTB autografts at 5-8 months and 9-15-months postoperatively.

LEVEL OF EVIDENCE

III.

Quality of YouTube Videos Regarding Anterior Cruciate Ligament Reconstruction Using Quadriceps Tendon Autograft Is Unsatisfactory

PURPOSE

To assess the validity and informational value of teaching material regarding anterior cruciate ligament reconstruction (ACLR) using quadriceps tendon (QT) autograft provided on the YouTube video platform.

METHODS

An extensive systematic search of the YouTube video platform was performed, and all videos that met the criteria were included in the analysis. The analysis of the video content was performed using the DISCERN instrument, Journal of American Medical Association (JAMA) benchmark criteria, and Global Quality Score (GQS). The duration of the videos, the date of publication, and the number of likes and views were recorded. Furthermore, videos were categorized based on the source (physicians, companies, patients), the subject (surgical technique, patient experience and overview [overview videos were videos in which multiple aspects were analyzed]), and the type of content (educational or subjective patient experience).

RESULTS

A total of 88 videos were included in the analysis. Seventy-one (80.7%) videos were published by physicians, 15 (17.0%) by patients, and 2 (2.3%) by companies. The majority of the videos described various surgical techniques (59%-67.0%), 80.7% of the videos (72%-81.8%) had an educational nature, and the remaining 18.2% described patient experiences. The mean length of the videos was 8.21 ± 7.88 minutes. The mean number of views was 3,988.51 ± 9,792.98 (range 9-56,047), whereas the mean numbers of comments and likes were 30.07 ± 70.07 (range 0-493) and 4.48 ± 14.22 (range 0-82), respectively. The mean DISCERN score, JAMA score, and GQS were 27.43 ±11.56 (95% confidence interval [CI] 25.01-29.85; range: 17-68), 1.22 ± 0.85 (95% CI 1.04-1.40; range 0-3), and 1.82 ± 0.93 (95% CI 1.63-2.01; range 1-4), respectively. For all scores, videos published by physicians had greater quality (DISCERN score, JAMA score, and GQS) (P < .05). Among all of the analyzed videos, overview videos were of the highest quality (P < .05).

CONCLUSIONS

YouTube is a fast and open-access source of mass information. The overall quality of the videos on ACLR performed using QT autograft was unsatisfactory, demonstrating low educational quality and reliability. Currently, YouTube cannot be recommended as a reliable source of information on ACLR with the QT.

Weaker Quadriceps Muscle Strength With a Quadriceps Tendon Graft Compared With a Patellar or Hamstring Tendon Graft at 7 Months After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Impaired quadriceps muscle strength after anterior cruciate ligament reconstruction (ACLR) is associated with worse clinical outcomes and a risk of reinjuries. Yet, we know little about quadriceps muscle strength in patients reconstructed with a quadriceps tendon (QT) graft, which is increasing in popularity worldwide.

PURPOSE

To describe and compare isokinetic quadriceps strength in patients undergoing ACLR with a QT, hamstring tendon (HT), or bone-patellar tendon-bone (BPTB) autograft.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

We included patients with QT grafts (n = 104) and matched them to patients with HT (n = 104) and BPTB (n = 104) grafts based on age, sex, and associated meniscal surgery. Data were collected through clinical strength testing at a mean of 7 ± 1 months postoperatively. Isokinetic strength was measured at 90 deg/s, and quadriceps strength was expressed as the limb symmetry index (LSI) for peak torque, total work, torque at 30° of knee flexion, and time to peak torque.

RESULTS

Patients with QT grafts had the most impaired isokinetic quadriceps strength, with the LSI ranging between 67.5% and 75.1%, followed by those with BPTB grafts (74.4%-81.5%) and HT grafts (84.0%-89.0%). Patients with QT grafts had a significantly lower LSI for all variables compared with patients with HT grafts (mean difference: peak torque: -17.4% [95% CI, -21.7 to -13.2], P < .001; total work: -15.9% [95% CI, -20.6 to -11.1], P < .001; torque at 30° of knee flexion: -8.8% [95% CI, -14.7 to -2.9], P = .001; time to peak torque: -17.7% [95% CI, -25.8 to -9.6], P < .001). Compared with patients with BPTB grafts, patients with QT grafts had a significantly lower LSI for all variables (mean difference: peak torque: -6.9% [95% CI, -11.2 to -2.7], P < .001; total work: -7.7% [95% CI, -12.4 to -2.9], P < .001; torque at 30° of knee flexion: -6.3% [95% CI, -12.2 to -0.5], P = .03; time to peak torque: -8.8% [95% CI, -16.9 to -0.7], P = .03). None of the graft groups reached a mean LSI of >90% for peak torque (QT: 67.5% [95% CI, 64.8-70.1]; HT: 84.9% [95% CI, 82.4-87.4]; BPTB: 74.4% [95% CI, 72.0-76.9]).

CONCLUSION

At 7 months after ACLR, patients with QT grafts had significantly worse isokinetic quadriceps strength than patients with HT and BPTB grafts. None of the 3 graft groups reached a mean LSI of >90% in quadriceps strength.

Near complete quadriceps tendon healing 2 years following harvest in anterior cruciate ligament reconstruction

PURPOSE

Despite the recent increase in the use of quadriceps tendon (QT) autograft in anterior cruciate ligament reconstruction (ACLR); however, there remains a paucity of literature evaluating the postoperative morphology of the QT. The present study aimed to determine the postoperative morphologic change of the QT at a minimum of 2 years following harvesting during ACLR.

METHODS

Patients who underwent ACLR with QT autograft and underwent magnetic resonance imaging (MRI) at a minimum of 2 years following harvesting were retrospectively included in the study. The anterior-to-posterior (A-P) thickness, medial-to-lateral (M-L) width, cross-sectional area (CSA), and signal/noise quotient (SNQ) of the QT were assessed at 5 mm, 15 mm, and 30 mm proximal to the superior pole of the patella on MRI. The CSA was adjusted by the angle between the QT and the plane of the axial cut based on a cosine function (adjusted CSA). The A-P thickness, M-L width, adjusted CSA, and SNQ were compared pre- and postoperatively. In addition, defects or scar tissue formation in the harvest site were investigated on postoperative MRI.

RESULTS

Thirty patients were recruited for the study. The mean duration between postoperative MRI and surgery was 2.8 ± 1.1 years. The mean A-P thickness was 10.3% and 11.9% larger postoperatively at 5 mm and 15 mm, respectively. The mean M-L width was 7.3% and 6.5% smaller postoperatively at 5 mm and 15 mm, respectively. There were no significant differences in the adjusted CSA between pre- and post-operative states (275.7 ± 71.6 mm2 vs. 286.7 ± 91.8 mm2, n.s.). There was no significant difference in the postoperative change in the SNQ of the QT at all assessment locations. Defect or scar tissue formation at the harvest site was observed in 4 cases (13.3%), and 5 cases (16.6%), respectively.

CONCLUSION

At a minimum of 2 years following QT harvest during ACLR, the QT became slightly thicker and narrower (approximately 11% and 7%, respectively). While the current study demonstrates that QT re-harvesting can be considered due to nearly normalized tendon morphology, future histological and biomechanical studies are required to determine the re-harvesting potential of the QT.

LEVEL OF EVIDENCE

IV.

Differences in the microstructural and mechanical qualities of semitendinosus tendon grafts between skeletally immature and mature patients in anterior cruciate ligament reconstruction

BACKGROUND

This study aimed to investigate the microstructural and mechanical properties of semitendinosus tendon graft tissues during anterior cruciate ligament reconstruction and the clinical outcomes in skeletally immature and mature patients.

METHODS

Twenty-two patients who underwent primary anterior cruciate ligament reconstruction using a hamstring tendon graft were analyzed and divided into skeletally immature (n = 7) and mature groups (n = 15) based on magnetic resonance imaging findings of the epiphyseal plate of the distal femur. Tissue samples were collected from the mid-portion of the semitendinosus tendon. The collagen fibril diameter, maximum stress, and strain at maximum stress point in the semitendinosus tendon tissues were calculated for comparison of the microstructural and mechanical properties between the two groups. Postoperative outcomes were also assessed between the two groups.

RESULTS

The mean and 60th and 80th percentiles of fibril diameters in the skeletally immature group were significantly smaller than those in the mature group (65.9 ± 13.0, 73.5 ± 19.3, and 91.3 ± 27.4 nm in the skeletally immature group; and 90.3 ± 14.7, 94.0 ± 18.4, and 125.3 ± 19.9 nm in the skeletally immature group; p = 0.001, 0.024, and 0.004, respectively). Additionally, the strain at maximum stress was higher in the skeletally immature group (237.2 ± 102.4% vs. 121.5 ± 51.9%, p = 0.024). However, there was no difference in maximum stress between the skeletally immature and mature groups (19.9 ± 14.3 MPa vs. 24.5 ± 23.4 MPa, p = 0.578). Strain was negatively correlated with the mean fibril diameter and the 60th and 80th percentiles of fibril diameters, whereas stress was positively correlated with the mean fibril diameter. The skeletally immature group had a higher pivot shift test-positive rate than the mature group at the last follow-up (p = 0.023).

CONCLUSION

Semitendinosus tendon graft tissues differed microstructurally and mechanically between skeletally immature and mature patients.

LEVEL OF EVIDENCE

Level Ⅳ.

Harvest location has a minimal impact on differences in cross-sectional area of quadriceps tendon in anterior cruciate ligament reconstruction

PURPOSE

Anterior cruciate ligament (ACL) reconstruction with quadriceps tendon (QT) has been gaining popularity. However, it is unknown how differences in harvest location of the QT affect its thickness and cross-sectional area (CSA). The present study aimed to clarify the differences in thickness and CSA of the QT based on location of tendon harvesting.

METHODS

Patients scheduled for, or who underwent, ACL reconstruction were prospectively included in the study. The short-axis images on ultrasound were used to assess the CSA of the QT at 30 and 60 mm proximal to the superior pole of the patella. QT autografts with CSAs greater than or equal to 10 mm of width were included and measured at three different locations, namely the center, medial one-third, and lateral one-third at the widest diameter of the QT. Patients with less than 10-mm width of the QT at 60 mm proximal to the superior pole of the patella were excluded. The thickness and CSA were compared based on the location of tendon harvest.

RESULTS

Thirty-seven patients were recruited for the study. The mean thickness and CSA were larger in the center of the QT compared to the lateral one-third at 30 mm proximal to the superior pole of the patella (thickness, 6.7 ± 1.3 mm vs. 5.9 ± 1.3 mm; P = 0.009; CSA, 65.6 ± 11.4 mm2 vs. 58.8 ± 11.9 mm2; P = 0.036). There were no significant differences in thickness and CSA of the QT among the three assessment locations at 60 mm proximal to the superior pole of the patella (n.s.).

CONCLUSION

The thickness and CSA of QT was greater in the center compared to the lateral one-third at 30 mm proximal to the QT insertion point. However, the difference in value was clinically non-significant, and therefore, harvest location of the QT autograft may not meaningfully impact intraoperative graft diameter. As a result, surgeons may choose the harvest location without concern for resultant graft diameter as long as the enough length of QT is secured.

LEVEL OF EVIDENCE

III.

Revision Rates After Primary Allograft ACL Reconstruction by Allograft Tissue Type in Older Patients

Background

While there is extensive literature on the use of allograft versus autograft in anterior cruciate ligament (ACL) reconstruction, there is limited clinical evidence to guide the surgeon in choice of allograft tissue type.

Purpose

To assess the revision rate after primary ACL reconstruction with allograft and to compare revision rates based on allograft tissue type and characteristics.

Study Design

Cohort study; Level of evidence, 3.

Methods

Patients who underwent primary allograft ACL reconstructions at a single academic institution between 2015 and 2019 and who had minimum 2-year follow-up were included. Exclusion criteria were missing surgical or allograft tissue type data. Demographics, operative details, and subsequent surgical procedures were collected. Allograft details included graft tissue type (Achilles, bone-patellar tendon-bone [BTB], tibialis anterior or posterior, semitendinosus, unspecified soft tissue), allograft category (all-soft tissue vs bone block), donor age, irradiation duration and intensity, and chemical cleansing process. Revision rates were calculated and compared by allograft characteristics.

Results

Included were 418 patients (age, 39 ± 12 years; body mass index, 30 ± 9 kg/m2). The revision rate was 3% (11/418) at a mean follow-up of 4.9 ± 1.4 years. There were no differences in revision rate according to allograft tissue type across Achilles tendon (3%; 3/95), BTB (5%; 3/58), tibialis anterior or posterior (3%; 5/162), semitendinosus (0%; 0/46), or unspecified soft tissue (0%; 0/57) (P = .35). There was no difference in revision rate between all-soft tissue versus bone block allograft (6/283 [2%] vs 5/135 [4%], respectively; P = .34). Of the 51% of grafts with irradiation data, all grafts were irradiated, with levels varying from 1.5 to 2.7 Mrad and 82% of grafts having levels of <2.0 Mrad. There was no difference in revision rate between the low-dose and medium-to high-dose irradiation cohorts (4% vs 6%, respectively; P = .64).

Conclusion

Similarly low (0%-6%) revision rates after primary ACL reconstruction were seen regardless of allograft tissue type, bone block versus all-soft tissue allograft, and sterilization technique in 418 patients with mean age of 39 years. Surgeons may consider appropriately processed allograft tissue with or without bone block when indicating ACL reconstruction in older patients.

Risk Factors for Revision or Rerupture After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

The rerupture or need for revision after anterior cruciate ligament reconstruction (ACLR) is a serious complication. Preventive strategies that target the early identification of risk factors are important to reduce the incidence of additional surgery.

PURPOSE

To perform a systematic review and meta-analysis to investigate risk factors for revision or rerupture after ACLR.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

Literature searches were performed in PubMed, Embase, and Web of Science from database inception to November 2021 and updated in January 2022. Quantitative, original studies reporting potential adjusted risk factors were included. Odds ratios (ORs) were calculated for potential risk factors.

RESULTS

A total of 71 studies across 13 countries with a total sample size of 629,120 met the inclusion criteria. Fifteen factors were associated with an increase in the risk of revision or rerupture after ACLR: male sex (OR, 1.27; 95% CI, 1.14-1.41), younger age (OR, 1.07; 95% CI, 1.05-1.08), lower body mass index (BMI) (OR, 1.03; 95% CI, 1.00-1.06), family history (OR, 2.47; 95% CI, 1.50-4.08), White race (OR, 1.32; 95% CI, 1.08-1.60), higher posterolateral tibial slope (OR, 1.15; 95% CI, 1.05-1.26), preoperative high-grade anterior knee laxity (OR, 2.30; 95% CI, 1.46-3.64), higher baseline Marx activity level (OR, 1.07; 95% CI, 1.02-1.13), return to a high activity level/sport (OR, 2.03; 95% CI, 1.15-3.57), an ACLR within less than a year after injury (OR, 2.05; 95% CI, 1.81-2.32), a concomitant medial collateral ligament (MCL) injury (OR, 1.62; 95% CI, 1.31-2.00), an anteromedial portal or transportal technique (OR, 1.36; 95% CI, 1.22-1.51), hamstring tendon (HT) autografts (vs bone-patellar tendon-bone [BPTB] autografts) (OR, 1.60; 95% CI, 1.40-1.82), allografts (OR, 2.63; 95% CI, 1.65-4.19), and smaller graft diameter (OR, 1.21; 95% CI, 1.05-1.38). The other factors failed to show an association with an increased risk of revision or rerupture after ACLR.

CONCLUSION

Male sex, younger age, lower BMI, family history, White race, higher posterolateral tibial slope, preoperative high-grade anterior knee laxity, higher baseline Marx activity level, return to a high activity level/sport, an ACLR within less than a year from injury, a concomitant MCL injury, an anteromedial portal or transportal technique, HT autografts (vs BPTB autografts), allografts, and smaller graft diameter may increase the risk of revision or rerupture after ACLR. Raising awareness and implementing effective preventions/interventions for risk factors are priorities for clinical practitioners to reduce the incidence of revision or rerupture after ACLR.

Quadriceps and hamstring anterior cruciate ligament reconstruction differ only marginally in function after the rehabilitation: a propensity score-matched case-control study

PURPOSE

To determine potential quadriceps versus hamstring tendon autograft differences in neuromuscular function and return to sport (RTS)-success in participants after an anterior cruciate ligament (ACL) reconstruction.

METHODS

Case-control study on 25 participants operated on with an arthroscopically assisted, anatomic ipsilateral quadriceps femoris tendon graft and two control groups of 25 participants each, operated on with a semitendinosus tendon or semitendinosus-gracilis (hamstring) tendon graft ACL reconstruction. Participants of the two control groups were propensity score matched to the case group based on sex, age, Tegner activity scale and either the total volume of rehabilitation since reconstruction (n = 25) or the time since reconstruction (n = 25). At the end of the rehabilitation (averagely 8 months post-reconstruction), self-reported knee function (KOOS sum scores), fear of loading the reconstructed knee during a sporting activity (RSI-ACL questionnaire), and fear of movement (Tampa scale of kinesiophobia) were followed by hop and jump tests. Front hops for distance (jumping distance as the outcome) were followed by Drop jumps (normalised knee joint separation distance), and concluded by qualitative ratings of the Balanced front and side hops. Between-group comparisons were undertaken using 95% confidence intervals comparisons, effect sizes were calculated.

RESULTS

The quadriceps case group (always compared with the rehabilitation-matched hamstring graft controls first and versus time-matched hamstring graft controls second) had non-significant and only marginal higher self-reported issues during sporting activities: Cohen's d = 0.42, d = 0.44, lower confidence for RTS (d = - 0.30, d = - 0.16), and less kinesiophobia (d =  - 0.25, d = 0.32). Small and once more non-significant effect sizes point towards lower values in the quadriceps graft groups in the Front hop for distance limb symmetry values in comparison to the two hamstring control groups (d =  - 0.24, d = - 0.35). The normalised knee joint separation distance were non-significantly and small effect sized higher in the quadriceps than in the hamstring groups (d = 0.31, d = 0.28).

CONCLUSION

Only non-significant and marginal between-graft differences in the functional outcomes at the end of the rehabilitation occurred. The selection of either a hamstring or a quadriceps graft type cannot be recommended based on the results. The decision must be undertaken individually.

LEVEL OF EVIDENCE

III.

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

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

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.

All-Soft Tissue Quadriceps Tendon Autograft in Revision Anterior Cruciate Ligament Reconstruction in Athletes: Comparison to Bone-Patellar Tendon-Bone Autograft With at Least a 2-Year Follow-up

BACKGROUND

Revision anterior cruciate ligament (ACL) reconstruction is being performed at an increasing rate. Previous literature has suggested that autograft ACL reconstruction is a better option than allograft in revision surgery, although the optimal autograft choice remains unknown. The all-soft tissue quadriceps tendon (ASTQT) autograft has been found to be an effective option for primary ACL reconstruction. However, few studies have evaluated ASTQT autograft in revision ACL reconstruction.

PURPOSE/HYPOTHESIS

The purpose of this study was to evaluate the ASTQT autograft in revision ACL reconstruction in athletes compared with bone-patellar tendon-bone (BTB) autograft. We hypothesized that the ASTQT autograft would lead to similar return to play, time to return to play, retear rate, and patient-reported outcomes compared with BTB autograft.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective study was performed on all athletes undergoing revision ACL reconstruction between August 2013 and December 2019 at a single institution. Patients participating in high school or college athletics undergoing first-time revision with either ASTQT or BTB autograft with ≥2 years of follow-up were included. Demographic variables, complications, return to sports, and outcome scores including the International Knee Documentation Committee (IKDC) and Lysholm were collected and compared between the 2 cohorts.

RESULTS

A total of 58 revision ACL reconstructions were included, with 32 in the ASTQT cohort and 26 in the BTB cohort. Return to sports at the same level occurred in 62.5% of the ASTQT group and 53.8% of the BTB group. The ASTQT group returned to sports significantly faster than the BTB group (8.9 vs 10.3 months; P = .020). There was no difference in retear rates (3.1%, ASTQT; 7.7%, BTB) or other complications between the 2 groups. The IKDC scores were significantly higher at the 6- and 12-month follow-up for the ASTQT autograft group compared with the BTB group (6 months: ASTQT, 71.3; BTB, 61.7, P = .001; 12 months: ASTQT, 82.7; BTB, 78.6; P = .021). Lysholm scores were also greater in the ASTQT cohort at these time points (6 months: ASTQT, 75.1; BTB, 63.6; P < .001; 12 months: ASTQT, 82.0; BTB, 74.5; P < .001). However, IKDC and Lysholm scores were similar between both groups at final follow-up (IKDC: ASTQT, 82.9; BTB, 81.7; P = .344; Lysholm: ASTQT, 83.0; BTB, 81.0; P = .104) There was no significant clinical difference in the absolute difference in scores or rate of achieving clinical thresholds between the 2 cohorts.

CONCLUSION

ASTQT autograft for revision ACL in athletes has similar outcomes compared with BTB autograft. However, the ASTQT may possibly afford quicker return to sports and better early improvements in patient-reported outcomes that normalize by 1 year. The soft tissue quadriceps autograft should be considered a viable graft option in revision ACL reconstruction in athletes.

Anterior cruciate ligament reconstruction with all-soft tissue quadriceps tendon versus quadriceps tendon with bone block

PURPOSE

The purpose of this study was to evaluate whether there was a difference in clinical outcomes between patients who underwent primary ACL reconstruction (ACLR) with all-soft tissue quadriceps tendon (sQT) autograft versus QT with bone block (bQT).

METHODS

A retrospective cohort study of 708 patients who underwent QT ACLR was conducted. Primary ACLR patients with at least 1 year of follow-up were identified and those who received sQT were compared to those who received bQT. Data collection entailed patient demographics, surgical variables, patient reported outcomes (PROs), knee stability testing, and complications. The primary outcome of interest was International Knee Documentation Committee (IKDC) score, reported as mean score, pre- and postoperative difference, and number who met minimum clinically important difference (MCID). Secondary outcomes included Lachman and pivot shift grade, other patient reported outcomes (PROs), complication rates, and return to sport (RTS).

RESULTS

A total of 195 patients (147 sQT, 48 bQT) who underwent primary QT ACLR met criteria for analysis, with mean follow-up of 17.0 ± 7.9 months. No difference was detected between cohorts with respect to postoperative IKDC score (sQT: n = 120, 81.0 ± 18.9, bQT: n = 10, 80.9 ± 20.4, n.s.), proportion of patients who met MCID (sQT: 68/78 [87%], bQT: 6/7 [86%], n.s.), or results of stability testing. In the sQT cohort, 86% (106/123) of athletes achieved full RTS, compared to 85% (34/40) in the bQT cohort (n.s.). Time to RTS was less than a year in both cohorts (sQT: 10.5 ± 3.8 months [n = 106], bQT: 11.1 ± 3.9 months [n = 31], n.s.). Graft rupture occurred in 7 (5%) sQT patients and 3 (6%) bQT patients (n.s.), and all clinical failures were due to graft rupture (n.s.). No differences were detected for rates of postoperative complications.

CONCLUSION

No differences in clinical outcomes were detected between patients who underwent primary ACLR with sQT autograft versus bQT autograft. Currently, the decision to employ sQT or bQT is largely determined by surgeon preference. This study demonstrates excellent outcomes with both preparations and supports the use of either graft type at the discretion of the treating surgeon.

LEVEL OF EVIDENCE

III.