Comparison of Neuromuscular Firing Patterns of the Superficial Quadriceps in Soft Tissue Quadriceps Tendon Versus Bone-Patellar Tendon-Bone ACL Autografts

No increased complication rate with the use of soft tissue quadriceps tendon autograft for primary ACL reconstruction - a systematic review

BACKGROUND

The autograft of choice for anterior cruciate ligament reconstruction (ACLR) remains debateable. Recently there has been increased popularity of soft tissue quadriceps tendon (s-QT) autograft due to less donor site morbidity, reduced anterior knee pain and comparable re-operation and complication rates. The aim of this review was to analyse functional outcomes of primary ACLR using s-QT in adult population without the bone plug and to report its complication profile against other autografts.

PATIENT AND METHODS

This systematic review was performed in accordance with PRISMA guidelines and a review of literature was conducted on four online databases (Medline, EMBASE, Cochrane and Google Scholar). Clinical studies reporting on patients undergoing primary ACLR with s-QT autograft or in comparison to BPTB or HS autografts with a minimum of 6 months follow-up were included. The studies were inclusive of only all soft tissue QT autograft regardless of the implants or fixation method used. Critical appraisal of studies was conducted using the Methodological Index for Non-Randomized Studies (MINORS) tool.

RESULTS

Fourteen studies were eligible. There were three randomised control studies (RCT) and 11 non-randomised comparative studies with 1543 patients who underwent ACLR. 682 underwent s-QT, 498 had hamstring tendon (HT) and 174 had bone-patellar tendon-bone (BPTB). 60% (n = 930) were males and mean follow up was 23.6 months (6-65). Eight studies reported post-operative patient reported outcome measures (PROMs). The mean International Knee Documentation Committee (IKDC) score was 91.5 ± 15.1 whereas mean Lysholm score was 90 ± 3.9. Five studies reported on laxity with mean anterior tibial translation (ATT) of 1.28 ± 1.09 mm. Overall complication rate of s-QT ACLR was 6% with 3% graft failure, 0.52% arthrofibrosis, 0.2% infection, 0.75% revision ACLR. There was no significant difference in functional outcome scores, knee stability and range of motion (ROM) between s-QT, HT and BPTB.

CONCLUSION

s-QT for ACLR has a comparable functional outcome, laxity, failure and with overall graft failure rate of 3%.

LEVEL OF EVIDENCE

III; Systematic review and meta-analysis.

The Associations Between Quadriceps Tendon Graft Thickness and Isokinetic Performance

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) using the quadriceps tendon is an increasingly popular technique. Both partial-thickness quadriceps tendon (PT-Q) and full-thickness quadriceps tendon (FT-Q) graft depths are employed.

HYPOTHESIS/PURPOSE

This study was designed to assess isokinetic peak torque, average power, and total work during knee extension in patients with FT-Q or PT-Q grafts for ACLR. We hypothesized that both groups would show lower isokinetic values for the operated side, with greater deficits in the FT-Q group than in the PT-Q group.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A total of 26 patients who underwent ACLR with either an FT-Q or PT-Q graft were recruited between June 2021 and November 2021. Patients underwent isokinetic knee extension testing at > 1 year after surgery. Mixed repeated-measures analysis of covariance with least square difference post hoc testing was used to determine significant differences or interactions for all variables.

RESULTS

Peak torque was significantly lower for the operated limb than the nonoperated limb in the FT-Q group (mean difference [MD] ± standard error [SE], -38.6 ± 8.3 Nċm [95% CI, -55.7 to -21.5 Nċm]; P < .001; d = 0.90) but not in the PT-Q group (MD ± SE, -7.3 ± 7.7 Nċm [95% CI, -23.2 to 8.5 Nċm]; P = .348; d = 0.20). Similarly, average power for the operated limb was lower than that for the nonoperated limb in the FT-Q group (MD ± SE, -53.6 ± 13.4 W [95% CI, -81.3 to -26.9 W]; P < .001; d = 0.88) but not in the PT-Q group (MD ± SE, -4.1 ± 12.4 W [95% CI, -29.8 to 21.5 W]; P = .742; d = 0.07), and total work was lower for the operated limb compared with the nonoperated limb in the FT-Q group (MD ± SE, -118.2 ± 27.1 J [95% CI, -174.3 to -62.2 J]; P < .001; d = 0.96) but not in the PT-Q group (MD ± SE, -18.3 ± 25.1 J [95% CI, -70.2 to 33.6 J]; P = .472; d = 0.15).

CONCLUSION

The FT-Q group showed significant deficits in the operated limb compared with the nonoperated limb for all isokinetic variables. In contrast, no significant differences were found between the nonoperated and operated limbs for the PT-Q group.

Closure of the Quadriceps Tendon Autograft Harvest Site for Anterior Cruciate Ligament Reconstruction: A Systematic Review

BACKGROUND

The quadriceps tendon (QT) autograft is a commonly used and effective graft option for anterior cruciate ligament reconstruction (ACLR). Surgical techniques vary, and there is no current standard of care for management of the QT autograft harvest site.

PURPOSE

To examine the literature on patient-reported outcomes and complications after ACLR with a QT autograft and to further clarify the frequency with which the harvest site is closed and potential biomechanical implications.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was performed using multiple medical databases. Level 1 to 4 studies on patients undergoing ACLR with a QT autograft were included. There were 2 independent reviewers who analyzed all studies. Study quality was analyzed using the methodological index for non-randomized studies checklist.

RESULTS

Overall, 13 studies with a total of 650 patients were included. The mean patient age for all studies was 31 years (range, 14-59 years) with a mean follow-up of 21.2 months (range, 6-84 months). Of the 13 studies, 12 studies (92%) documented patient sex, comprising 331 female patients (55%) and 274 male patients (45%). There were 8 studies (62%) that reported the use of a bony QT autograft in 273 patients, and 5 studies (38%) reported the use of a soft tissue QT autograft in 377 patients. The graft length harvested was most commonly 7 to 8 cm, while the tendon width harvested was 10 mm. Moreover, 5 studies (38%) did not discuss closure of the harvest site, while 2 studies (15%) only closed the harvest site if a capsular rent was present. The surgical technique for harvest-site closure varied when reported in 7 studies (54%). Good to excellent clinical outcomes were reported in 80% of patients when the harvest site was closed.

CONCLUSION

Based on the results of this study, there is no consensus on whether the QT defect should be closed after harvesting the graft for ACLR. It has been reported that closure of the harvest site is performed if there is a capsular rent present. Several techniques are utilized to close the QT autograft harvest site; however, it is unclear if there is a difference in outcomes based on the technique used. Future studies should further clarify whether there are any biomechanical and clinical advantages to closing the QT autograft harvest site.

Quadricep ACL Reconstruction Techniques and Outcomes: an Updated Scoping Review of the Quadricep Tendon

PURPOSE OF REVIEW

The purpose of this review is to provide an up-to-date summary on the most recent literature examining techniques and outcomes in anterior cruciate ligament (ACL) reconstruction using quadriceps tendon (QT) which will enable surgeons to make well informed evidence-based decisions when choosing a particular graft option and technique in ACL reconstruction.

RECENT FINDINGS

Several RCTs and systematic reviews have been published recently on this topic, and overall, there were no differences found between the QT, HT, and BPTB groups in patient-reported outcomes, stability testing, or graft re-rupture rates. In terms of strength testing, the QT group did have inferior knee extensor strength on isokinetic testing when compared to the HT group, whereas the HT group had inferior knee flexor strength compared to the QT group. No differences were found on strength testing between the QT and BPTB groups. Currently, two large RCTs, the Stability2 and SQuASH trials, are ongoing examining the effectiveness of the QT vs BPTB with or without LET and QT vs HT in the pediatric population which will help shed further light on the effectiveness of the QT as a graft choice in ACL reconstruction. The findings of this scoping review demonstrate that the QT is an excellent graft option in ACL reconstruction both in the primary and revision settings, among adult and pediatric populations. This review provides surgeons with further assurance when selecting QT autograft in ACL reconstruction.

Association Between Neuromuscular Variables and Graft Harvest in Soft Tissue Quadriceps Tendon Versus Bone-Patellar Tendon-Bone Anterior Cruciate Ligament Autografts

Background:

Quadriceps tendon (QT) autografts are increasingly popular for anterior cruciate ligament reconstruction (ACLR). However, no study has compared QT autografts with bone–patellar tendon–bone (BTB) autografts regarding the electromechanical delay (EMD), the peak torque (PT), and the rate of force development (RFD) in the superficial quadriceps muscles (rectus femoris [RF], vastus medialis [VM], and vastus lateralis [VL]).

Hypotheses:

We hypothesized (1) there would be a significantly lower PT, lower RFD, and longer quadriceps EMD of the operative limb for the QT versus the BTB autograft; (2) the PT, the RFD, and the quadriceps EMD of the operative limb would be significantly depressed compared with those of the nonoperative limb, regardless of the surgical technique; and (3) there would be greater increases in the RF EMD than in the VM or the VL EMD.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 34 patients (age, 18-40 years), who had undergone ACLR (QT, n = 17; BTB, n = 17) at least 1 year before testing and performed 3 perceived maximal effort isometric tests, which were time synchronized with surface electromyography (EMG) on their operative and nonoperative limbs, were included in this study. EMD, PT, and RFD data were analyzed using a 2 (limb) × 2 (graft) × 3 (repetition) mixed repeated-measures analysis of variance.

Results:

The EMD, the PT, and the RFD were not significantly affected by graft choice. For the VL, a significant repetition × graft × limb interaction was detected for the VL EMD (P = .027; ηp = 0.075), with repetition 3 having longer EMD than repetition 2 (mean difference [MD], 16 milliseconds; P = .039). For the RF EMD, there was a significant repetition × limb interaction (P = .027; ηp = 0.074), with repetition 3 being significantly longer on the operative versus the nonoperative limb (MD, 24 milliseconds; P = .004). Further, the operative limb EMD was significantly longer for repetition 3 versus repetition 2 (MD, 17 milliseconds; P = .042). For the PT, there was a significant effect for repetition (P = .003; ηp = 0.114), with repetition 1 being significantly higher than both repetitions 2 (MD, 8.52 N·m; P = .001) and 3 (MD, 7.79 N·m; P = .031). For the RFD, significant limb (P = .034; ηp = 0.092) and repetition (P = .010; ηp = 0.093) effects were seen, with the nonoperative limb being significantly faster than the operative limb (MD, 23.7 N·m/s; P = .034) and repetition 1 being significantly slower than repetitions 2 (MD, -20.46 N·m/s; P = .039) or 3 (MD, −29.85 N·m/s; P = .002).

Conclusion:

The EMD, the PT, and the RFD were not significantly affected by graft type when comparing QT and BTB autografts for ACLR; however, all neuromuscular variables were affected regardless of the QT or the BTB harvest.

Knee muscle strength after quadriceps tendon autograft anterior cruciate ligament reconstruction: systematic review and meta-analysis

PURPOSE

Restoration of knee muscle strength is associated with better outcomes following anterior cruciate ligament (ACL) reconstruction, but little is known about the outcome of strength following quadriceps tendon autograft (QT) ACL reconstruction in relation to other graft types. The aim of this review was to evaluate strength outcomes of the knee extensors and knee flexors following QT ACL reconstruction compared to (1) the non-reconstructed contralateral limb and (2) alternative ACL graft types.

METHODS

Four electronic databases were searched up until 21st February 2020. Summary meta-analyses were performed comparing knee strength outcomes following QT ACL reconstruction to the contralateral limb by way of limb symmetry index (LSI). Comparative meta-analyses were performed comparing QT ACL reconstruction to alternative ACL grafts for the two most frequently reported strength outcome measures which were peak knee extensor torque LSI, and peak knee flexor torque LSI at the following post-operative periods: 3, 5-8, 9-15, 24, 36-60 months.

RESULTS

In total, 18 studies met the inclusion criteria. Knee strength outcomes of 952 QT ACL reconstructions were included and compared to either the contralateral limb or 1 of 4 alternative ACL graft types; 245 hamstring tendon autograft (HT), 143 patellar tendon autograft (PT), 45 quadriceps tendon allograft, and 21 tibialis anterior allograft. Knee extensor strength LSI following QT ACL reconstruction did not reach 90% even at 24 months post-operatively. Conversely, knee flexor strength LSI following QT ACL reconstruction exceeded 90% at the 9-15 months post-operative period. Knee extensor strength at 5-8 months following QT ACL reconstruction appears similar to PT but weaker than HT ACL reconstruction. In addition, peak knee flexor LSI was significantly greater at 5-8 months in QT ACL reconstruction patients compared to HT patients.

CONCLUSION

The decision to utilize a QT graft for ACL reconstruction should include consideration of strength outcomes. Knee extensor strength recovery following QT ACL reconstruction appears not to be restored before 24 months.

LEVEL OF EVIDENCE

Level IV.

Anterior Cruciate Ligament Reconstruction with Quadriceps Tendon-Patellar Bone Autograft and Dual Tibial Fixation

Anterior cruciate ligament ruptures are a relatively common injury in the athletic population, and surgical reconstruction is often indicated to restore knee stability. While hamstring tendon and patellar bone-tendon-bone autografts are a well-established graft choice in this population, there has been a growing body of literature supporting the benefits of quadriceps tendon autograft. Our technique illustrates a full-thickness quadriceps tendon-patellar bone autograft with dual tibial fixation using an interference screw and backup suspensory anchor fixation.

Age, rehabilitation and surgery characteristics are re-injury risk factors for adolescents following anterior cruciate ligament reconstruction

OBJECTIVES

To examine the effect of age on post-ACLR rehabilitative outcomes and identify surgical/rehabilitative characteristics as ACL re-injury risk factors in adolescents.

DESIGN

Cohort study.

SETTING

Children's hospital.

PARTICIPANTS

273 adolescents with first-time ACLR.

MAIN OUTCOME MEASURES

Demographics, injury history, surgery, and outcomes documented during post-ACLR physical therapy (PT) sessions were extracted from medical records. Effects of age on outcomes were examined using multivariate regression. ACL re-injury risk factors were identified using survival analysis with Cox regression.

RESULTS

Re-injury was recorded in 47 patients (17.2%) with a median follow-up time of 3.1 years and median re-injury time of 13.4 months post-surgery. Younger age (Hazard-Ratio, HR = 1.264 per year decrease; P = 0.005), receiving surgery within 1 month post-injury (HR = 3.378 vs. >3 months; P = 0.012), starting PT within 3 days post-surgery (HR = 3.068; P = 0.022), and decreased number of PT sessions (HR = 1.118 per 3-session decrease; P = 0.010) increased re-injury risk. Although age was associated with re-injury risk, age was not associated with any outcome (P > 0.059).

CONCLUSION

Adolescents who are younger, receive surgery and post-surgery PT sooner, or attend fewer PT sessions may be at an increased re-injury risk. Younger patients achieved similar outcomes despite elevated re-injury risk. Current discharge criteria are inadequate in identifying high re-injury risk patients.