Quadriceps tendon: the forgotten graft

Females demonstrate lower levels of activity, psychological readiness and strength symmetry after anterior cruciate ligament reconstruction than males, and also recovery of quadriceps strength and hop symmetry is delayed in females undergoing reconstruction with a quadriceps tendon autograft

PURPOSE

To investigate sex-based recovery differences in patients undergoing anterior cruciate ligament reconstruction (ACLR) with a hamstring (HT) or quadriceps (QT) tendon autograft.

METHODS

This study included 97 patients, including 50 females (HT = 25, QT = 25) and 47 males (HT = 24, QT = 23), assessed presurgery and at 12- and 24-month postoperatively via surveys, laxity, isokinetic knee extensor and flexor torque and a 6-hop performance battery. Limb symmetry indices (LSIs) were calculated. Outcomes were compared between males and females, as well as within each graft type.

RESULTS

Males reported significantly higher Tegner scores at 12 (p = 0.029) and 24 (p = 0.031) months, Anterior Cruciate Ligament Return to Sport after Injury scores at 12 (p = 0.009) and 24 (p = 0.010) months, and a significantly higher lateral hop LSI at 12 (p = 0.045) months, knee extensor torque LSI at 12 (p = 0.020) months, and knee flexor torque LSI at 12 (p = 0.001) and 24 (p = 0.039) months. Females undergoing ACLR with a QT (vs. HT) graft demonstrated a lower knee extensor torque LSI at 12 (p = 0.006) months, a lower lateral hop LSI at 12 (p = 0.038) months, and a lower medial hop LSI at 12 (p = 0.042) months.

CONCLUSIONS

Females reported less activity and psychological readiness, as well as strength symmetry. Furthermore, the recovery of quadriceps strength and hop symmetry was delayed in females (vs. males) undergoing ACLR with a QT graft. A better understanding of these differences will assist in counselling on expectations, determining the most appropriate graft construct and permitting more targeted rehabilitation.

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).

Autograft patellar bone-tendon-bone use does not increase operative time in anterior cruciate ligament reconstruction

Background

Anterior cruciate ligament reconstruction (ACLR) is a common procedure that has been shown to have relatively good outcomes amongst various graft types. Operative time in ACLR has been found to influence outcomes and cost. The purpose of this study was to evaluate the association of operative time in primary arthroscopically performed anterior cruciate ligament reconstruction (ACLR) and graft type while controlling for confounders that influence time.

Methods

All patients who received ACLR between 2018 and 2022 were included in this retrospective cohort study. Exclusion criteria consisted of age (≤16 years), revisions, concomitant ligament reconstruction or tendon repairs, or other simultaneously performed procedures that could potentially add substantial variation in operative time. The primary outcome was operative time. Graft types included allograft, bone-tendon-bone (BTB) autograft, hamstring tendon (HS) autograft and quadriceps tendon (QT) autograft.

Results

A total of 1813 primary ACLRs were included. The average operative time was 98.9 ± 33.0 min. Graft utilization varies considerably among surgeons. The most used graft type was BTB autograft (42.6%) followed by HS autograft (32.3%) and allograft (21.4%). Only 68 cases (3.8%) used a QT autograft. Seven of the 15 included surgeons primarily used BTB autograft. One surgeon predominately used QT autograft. No difference in operative time was observed among the autograft types (p = 0.342). Allograft ACLR was significantly faster by 27-33 min compared to using BTB autograft, HS autograft, or QT autograft (p < 0.001).

Conclusion

Operative time did not vary by type of autograft selected. Allograft ACLR was performed approximately 30 min faster than autograft ACLR. Further studies examining the effect on patient outcomes of reduced operative time and minimizing graft harvest morbidity in ACLR is important to more accurately determine the cost-effectiveness of allograft ACLR.

"Luggage Tag" Suture Modification for Closing the Quadriceps Tendon Autograft Harvest Site

The quadriceps tendon (QT) is increasingly used as an autograft for anterior cruciate ligament reconstruction. Closure of the harvest site helps with fluid extravasation from the joint for the duration of the procedure. In addition, closure of the QT removes the palpable defect noticed by many patients and prevents superficial infections from spreading deep to the joint. This Technical Note describes how to perform the "luggage tag" suture modification to efficiently and reproducibly close the QT harvest site with an arthroscopic self-retrieving suture passer.

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

BACKGROUND

The best type of autograft for anterior cruciate ligament (ACL) reconstruction remains debatable.

HYPOTHESIS

Compared with bone-patellar tendon-bone (BPTB) and hamstring tendon (HT) autografts, the quadriceps tendon (QT) autograft has comparable graft survival as well as clinical function and pain outcomes.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

A systematic literature search was conducted in PubMed, Embase, Scopus, and the Cochrane Library to July 2020. Randomized controlled trials (RCTs) and observational studies reporting comparisons of QT versus BPTB or HT autografts for ACL reconstruction were included. All analyses were stratified according to study design: RCTs or observational studies.

RESULTS

A total of 24 studies were included: 7 RCTs and 17 observational studies. The 7 RCTs included 388 patients, and the 17 observational studies included 19,196 patients. No significant differences in graft failure (P = .36), the International Knee Documentation Committee (IKDC) subjective score (P = .39), or the side-to-side difference in stability (P = .60) were noted between QT and BPTB autografts. However, a significant reduction in donor site morbidity was noted in the QT group compared with the BPTB group (risk ratio [RR], 0.17 [95% CI, 0.09-0.33]; P < .001). No significant differences in graft failure (P = .57), the IKDC subjective score (P = .25), or the side-to-side stability difference (P = .98) were noted between QT and HT autografts. However, the QT autograft was associated with a significantly lower rate of donor site morbidity than the HT autograft (RR, 0.60 [95% CI, 0.39-0.93]; P = .02). A similar graft failure rate between the QT and control groups was observed after both early and late full weightbearing, after early and late full range of motion, and after using the QT autograft with a bone plug and all soft tissue QT grafts. However, a significantly lower rate of donor site morbidity was observed in the QT group compared with the control group after both early and late full weightbearing, after early and late full range of motion, and after using the QT autograft with a bone plug and all soft tissue QT grafts. No difference in effect estimates was seen between RCTs and observational studies.

CONCLUSION

The QT autograft had comparable graft survival, functional outcomes, and stability outcomes compared with BPTB and HT autografts. However, donor site morbidity was significantly lower with the QT autograft than with BPTB and HT autografts.

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.

A Systematic Review and Meta-Analysis of Strength Recovery Measured by Isokinetic Dynamometer Technology after Anterior Cruciate Ligament Reconstruction Using Quadriceps Tendon Autografts vs. Hamstring Tendon Autografts or Patellar Tendon Autografts

Background: This systematic review and meta-analysis compared the isokinetic strength of the muscular knee joint between quadriceps tendon autografts (QTAs) and hamstring tendon autografts (HTAs) or patellar tendon autografts (PTAs) after anterior cruciate ligament (ACL) reconstruction by determining the isokinetic angular velocity and follow-up time points. The functional outcomes and knee stability at the same time points were also compared using isokinetic technology. Methods: Two independent reviewers searched the Medline (via PubMed search engine), Scopus, Web of Science and Cochrane Library databases to include full text comparative studies that assessed isokinetic strength test following ACL reconstruction. The DerSimonian and Laird method was used. Results: In total, ten studies were included; seven compared studies QTAs vs. HTAs, and three compared QTAs vs. PTAs. Five studies were included in the meta-analysis. Isokinetic strength data were reported 3, 6, 12 and 24 months after ACL reconstruction. Conclusions: The QTAs showed better and significant results with knee flexion compared with HTAs, similar results to PTAs at 6 and 12 months. While HTAs showed better and significant results with knee extension at 6 months and similar results at 12 months compared to QTAs. Furthermore, a standardized isokinetic strength test must be followed to achieve a more specific conclusion and better clinical comparison among participants.

No Difference in Complication Rates or Patient-Reported Outcomes Between Bone–Patella Tendon–Bone and Quadriceps Tendon Autograft for Anterior Cruciate Ligament Reconstruction

Purpose

To compare subjective outcomes and complications of anterior cruciate ligament reconstruction (ACLR) using either bone–patellar tendon–bone (BPTB) or quadriceps tendon (QT) autograft.

Methods

A retrospective analysis of prospectively collected data identified consecutive cohorts of patients undergoing ACLR with either BPTB or QT autograft. Patients with less than 12-month follow-up and those undergoing concomitant osteotomies, cartilage restoration, and/or other ligament reconstruction procedures were excluded. Pre- and postsurgical patient-reported outcomes including International Knee Documentation Committee, Knee Injury and Osteoarthritis Outcome Score, Patient-Reported Outcomes Measurement Information System (PROMIS), Single Assessment Numeric Evaluation, Tegner, and Marx were compared between groups. Complications requiring reoperation were recorded.

Results

One hundred nineteen patients met inclusion criteria, including 39 QT autografts and 80 BPTB autografts. Demographic information was comparable between groups. Mean follow-up was comparable between groups (QT 22.4 ± 10.6 months vs BPTB 28.5 ± 18.5 months, P = .06). At minimum 12-month follow-up (range 12.0-100.8 months), patients in both groups demonstrated statistically significant improvements in International Knee Documentation Committee (QT 60.0%, P < .0001; BPTB 57.7%, P < .0001), all Knee Injury and Osteoarthritis Outcome Score domains, PROMIS Mobility T-Score (QT 27.2%, P = .0001; BPTB 23.2%, P < .0001), PROMIS Global Physical Health (QT 14.4%, P = .002; BPTB 13.4%, P = .001), PROMIS Physical Function (QT 29.6%, P < .0001; BPTB 37.1%, P < .0001), PROMIS Pain Interference (QT –16.5%, P < .0001; BPTB –20.8%, P < .0001), Single Assessment Numeric Evaluation, (QT 76.9%, P < .0001; BPTB 73.3%, P < .0001), Tegner (QT 92.9%, P = .0002; BPTB 101.4%, P < .0001), and Marx (QT –26.6%, P = .02; BPTB –32.0%, P = .0002) with no statistically significant differences between the 2 groups. Overall postoperative reoperation rate did not differ between groups (QT 12.8% vs BPTB 23.8%, P = .2). Revision ACL reconstruction rate did not differ between groups (QT 5.1% vs BPTB 7.5%, P = .6).

Conclusions

Patients undergoing autograft ACLR with either BPTB or QT demonstrated significant subjective improvements in patient-reported outcomes from preoperative values and no statistically significant differences in outcomes between the groups. Complication and revision ACLR rates were similar between the 2 groups.

Level of Evidence

III, retrospective cohort study.

Patellar Size Variation at the Quadriceps Tendon-Bone Block Harvest Site: A Magnetic Resonance Imaging Study to Evaluate the Safe Zone for Harvesting a Sufficient Bone Block

BACKGROUND

Quadriceps tendon (QT) autografts with and without a bone block are the least studied and least used options for anterior cruciate ligament reconstruction surgery. In particular, there is a lack of literature describing patellar anatomy. Until now, guidelines for patellar bone block harvesting have been based solely on personal experience. In this study, we intended to derive recommendations from physical regularities and objective criteria.

PURPOSE

To determine the maximal, individual-related length and depth of the bone block that can be safely harvested and to provide guidelines to help surgeons make decisions on graft choice.

STUDY DESIGN

Descriptive laboratory study.

METHODS

The study group consisted of 50 male participants and 50 female participants (mean age, 29.4 ± 7.9 years) who underwent 3.0-T magnetic resonance imaging of their knee. Patellar height was determined at the center of the middle third of the QT insertion on the patella and the medial and lateral endpoints; the depth was measured at the midpoints of the respective heights.

RESULTS

The mean width of the QT and the mean thickness were 49.0 ± 7.6 and 7.3 ± 1.0 mm, respectively. The mean patellar thickness in reference to the medial endpoint, the center, and the lateral endpoint was 18.3 ± 2.4, 17.9 ± 2.3, and 15.1 ± 2.3 mm, respectively, whereas the mean patellar height was 35.1 ± 4.1, 36.7 ± 4.2, and 35.1 ± 3.9 mm. In general, the tendon and patellar dimensions were significantly larger in male participants than in female participants (P = .016).

CONCLUSION

Bone block harvesting, with its depth not exceeding 50% of the patellar thickness and its length accounting for <50% of the patellar height, poses the least risk for a patellar fracture when located medial to midline. If the bone block is excised from the medial half of the central area (the latter is defined by the middle third of the QT insertion), with the outer edge of the saw positioned at the medial border of the central area, a graft of 15 mm length, 10 mm width, and 8 mm depth can be safely harvested in all White male participants and almost all female participants taller than 165 cm, according to our findings.

CLINICAL RELEVANCE

This is the first study presenting recommendations for patellar bone block harvesting at the quadriceps tendon insertionbased on physical regularities and objective criteria and not on personal experience.

ACL Study Group survey reveals the evolution of anterior cruciate ligament reconstruction graft choice over the past three decades

PURPOSE

Anterior cruciate ligament reconstruction (ACLR) aims to restore knee function and stability, allowing patients to return to the activities they enjoy and minimize further injury to the meniscus and cartilage and their ultimate progression to osteoarthritis. This study aims to present the evolution of graft choice over the last three decades according to members of the ACL Study Group (SG).

METHODS

Prior to the January 2020 ACL SG biannual meeting, a survey was administered consisting of 87 questions and 16 categories, including ACLR graft choice. A similar questionnaire has been administered prior to each meeting and survey results from the past 14 meetings (1992 through 2020, excluding 1994) are included in this work. Survey responses are reported as frequencies in percentages to quantify changes in practice over the surgery period.

RESULTS

In 1992, the most frequent graft choice for primary ACLR was bone-patellar tendon-bone (BTB) autograft, at nearly 90%. Hamstring tendon (HT) autografts have increased in popularity, currently over 50%, followed by just under 40% BTB autograft. Recently, quadriceps tendon (QT) autograft has increased in popularity since 2014.

CONCLUSION

Autograft (HT, BTB, QT) is an overwhelming favorite for primary ACLR over allograft. The preference for HT autograft increased over the study period relative to BTB autograft, with QT autograft gaining in popularity in recent years. Graft selection should be individualized for each patient and understanding the global trends in graft choice can help orthopaedic surgeons discuss graft options with their patients and determine the appropriate graft for each case.

LEVEL OF EVIDENCE

Level V, Expert Opinion.

Revision Anterior Cruciate Ligament Reconstruction with the All-Soft Tissue Quadriceps Tendon Autograft Has Acceptable Early and Intermediate-Term Outcomes

PURPOSE

The purposes were to (1) examine early to intermediate-term clinical outcomes and complications of revision anterior cruciate ligament reconstruction (ACLR) using all-soft tissue quadriceps tendon (QT) autografts, and (2) compare quadriceps strength between patients who had hamstring versus patella tendon autografts in their previous reconstruction.

METHODS

One hundred patients (52 males/48 females; 22.6 ± 8.0 years) undergoing revision ACLR with all-soft tissue QT autografts were prospectively followed. All revision procedures were performed by a single surgeon, using a minimally invasive graft harvest technique and suspensory fixation. Subjective assessment of knee function was obtained before and after surgery with the International Knee Documentation Committee (IKDC) survey. Postoperative knee laxity and isokinetic quadriceps strength were collected at regular intervals. Strength was reported as limb symmetry index (LSI; surgical side divided by nonsurgical side). Complications including hematomas, postoperative loss of knee extension, and graft failures were recorded. To determine clinical significance (P ≤ .05), outcomes were compared using analysis of variance or paired samples t-tests.

RESULTS

The mean IKDC scores significantly improved (54.3 ± 13.0 vs 82.8 ± 13.8), with an average follow-up of 42.2 ± 21.2 months. There were no significant changes in knee laxity side-to-side differences: 6 weeks (1.2 ± 1.5 mm), 3 months (1.2 ± 1.8 mm), 6 months (1.4 ± 1.6 mm). Quadriceps LSIs significantly improved from 71.6% ± 19.3% at 6 months to 81.5% ± 19.3% at 12 months for 60°/s isokinetic testing and 76.6% ± 16.4% at 6 months to 83.9% ± 16.9% at 12 months for 180°/s testing. Graft harvest site hematomas developed in 2 patients, postoperative loss of knee extension in 4 patients, and graft failure in 11 patients. No significant differences in quadriceps or hamstrings LSIs were noted between patients with previous hamstring versus patella tendon autografts (P > .050).

CONCLUSION

Revision ACLR with all-soft tissue QT autografts has acceptable early and intermediate-term outcomes with reasonable complication rates (11/80 patients with follow-up). Secondary insult to the extensor mechanism via QT autograft harvest does not adversely affect strength after prior patellar tendon versus hamstring autograft.

LEVEL OF EVIDENCE

Level IV, cases series subgroup analysis.

Tendão quadricipital: Opção na reconstrução ligamentar do joelho

Although it is a versatile tendon, only 1% of surgeons choose to use the quadricipital tendon as a graft in anterior cruciate ligament (ACL) reconstruction. The present article aims to describe a quadricipital graft removal technique in which its deepest part is maintained. The technique consists of an approach in which the first incision is made in the medial part of the quadricipital tendon to prevent it from getting too short. This is due to its triangular design. The technique also addresses the depth and identification of the three layers of the quadricipital tendon so that it is possible to preserve its deepest part. This approach aims to preserve the extensor apparatus and to not communicate it with the joint environment, avoiding fluid extravasation both in the trans and postoperative periods.

A Comparison of Quadriceps Tendon Autograft With Bone-Patellar Tendon-Bone Autograft and Hamstring Tendon Autograft for Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review and Quantitative Synthesis

OBJECTIVE

There is growing enthusiasm for the increased use of quadriceps tendon (QT) autograft for primary anterior cruciate ligament reconstruction (ACLR). The purpose of this analysis was to synthesize and quantitatively assess the available evidence comparing QT autograft with hamstring tendon (HT) and bone-patellar tendon-bone (BPTB) autografts, regarding functional outcomes, knee stability, anterior knee pain, and revision rates.

DATA SOURCES

A search in MEDLINE, EMBASE, PubMed, and the Cochrane Central Register of Controlled Trials for eligible studies up to May 2018 was conducted. Two reviewers selected studies based on inclusion criteria and assessed methodological quality. Outcomes analyzed were anterior knee pain, graft failure rates, knee stability, functional outcomes, and adverse events. Pooled analyses were performed for continuous and dichotomous variables where appropriate.

MAIN RESULTS

Ten studies (1 randomized trial and 9 nonrandomized cohorts) met our inclusion criteria, which included 1398 patients. The analysis showed no statistical difference in anterior knee pain when comparing QT and HT autografts, but a significant difference between QT and BPTB autografts [odds ratio, 0.15 (95% confidence interval, 0.08-0.27); P < 0.001]. There were no differences between all 3 autografts in revision rates, knee stability, and patient-reported functional outcomes.

CONCLUSIONS

Quadriceps tendon autograft is a suitable graft alternative for primary ACLR, as it achieves good clinical outcomes with a low incidence of anterior knee pain. Given the limited quality of the included studies, there is a need for a well-designed multicenter randomized control trial comparing QT autograft with other primary ACL autografts to confirm our findings.

LEVEL OF EVIDENCE

Level IV systematic review.

The outcomes of quadriceps tendon autograft for anterior cruciate ligament reconstruction in adolescent athletes: a retrospective case series

BACKGROUND

Multiple graft options exist for anterior cruciate ligament (ACL) reconstruction in an adolescent athlete. Patellar tendon harvest can lead to anterior knee pain, while hamstring tendon harvest can affect knee flexion strength and alter mechanics. Allograft is less desirable in pediatric patients due to the higher failure rate and slight risk of disease transmission. Quadriceps tendon autograft has rarely been reported for adolescent ACL reconstruction in the USA, but is an excellent option due to its large size, low donor site morbidity, and versatility. The purpose of this study is to report the outcomes of adolescents who have undergone ACL reconstruction using quadriceps tendon autograft.

METHODS

Twenty-two ACL reconstructions using the quadriceps autograft were performed on 21 pediatric patients by the senior author between 2010 and 2017. The patient's demographics, injury characteristics, imaging, physical examination findings, operative findings, outcomes and sports were recorded.

RESULTS

The average age at the time of surgery was 15 years. Two patients had open physes; the remainder had closing physes. 64% of patients had additional meniscal tears and 76% had bony contusions. The average duration of follow-up was 2.8 years (range 2-5 years). At final follow-up, there were no angular deformities or leg length discrepancies. The average quadriceps atrophy of the operative leg was 4 mm. The average Lysholm score was 98. 86% of patients returned to sports. No patients had re-rupture of their operative ACL. No incidences of infections, numbness, or anterior knee pain were reported. Two patients had a second arthroscopy for re-injury, revealing new meniscal tears but intact ACL grafts.

CONCLUSIONS

Use of quadriceps tendon autograft for ACL reconstruction in adolescent patients allows reliable return to sport with minimal complications.

LEVEL OF EVIDENCE

Level IV, retrospective case series.

Implications for Early Postoperative Care After Quadriceps Tendon Autograft for Anterior Cruciate Ligament Reconstruction: A Technical Note

The quadriceps tendon (QT) has become increasingly used by orthopaedic surgeons as an alternative autograft choice in anterior cruciate ligament reconstruction. As its use increases, athletic trainers and other rehabilitation clinicians will treat a greater number of patients with this autograft type. The recently developed, minimally invasive technique for harvest of the all-soft tissue autograft has many benefits, including versatility, decreased donor-site morbidity, and enhanced cosmesis. Early clinical trials revealed that the QT autograft resulted in decreased anterior knee pain and similar strength and functional outcomes to those of more common autograft types. From a rehabilitation perspective, many characteristics should be considered, such as the importance of early knee extension and quadriceps activation. Therefore, the purpose of this technical note is to expose athletic trainers to the QT autograft so that they may provide the best care for patients after anterior cruciate ligament reconstruction.

Comparative Efficacy of Graft Options in Anterior Cruciate Ligament Reconstruction: A Systematic Review and Network Meta-Analysis

Purpose

To evaluate the effectiveness of various graft options for anterior cruciate ligament reconstruction using network meta-analysis.

Methods

A medical literature search was conducted of PubMed, the Cochrane Library, Embase, SCOPUS, and Web of Science from their inception through March 1, 2019. The outcomes, including International Knee Documentation Committee (IKDC) form, Lachman test, Lysholm score, Pivot shift test, and Tegner score, were evaluated among graft options. Data extraction was carried out according to inclusion and exclusion criteria, and a network meta-analysis was performed using STATA 14.0.

Results

A total of 45 trials with 3992 patients were included. The forest plots revealed no significant differences in IKDC, Lysholm, or Tegner score among the grafts. In Lachman score, a significant difference was found in the comparisons of hamstring tendon allograft (HT-AL) versus patellar tendon autograft (PT-AU) and HT-AL versus hamstring tendon autograft (HT-AU). In pivot shift test, PT-AU was superior to all the other grafts, and quadriceps tendon autograft (QT-AU) was superior to HT-AL and artificial ligament (Art-L) in the number of cases with negative results. According to surface under the cumulative ranking area (SUCRA), PT-AU had the highest probability to be the best intervention in Lachman test and Tegner score; tibialis anterior tendon allograft (TA-AL) in IKDC and Lysholm score; and QT-AU in pivot shift test. Based on the cluster analysis of SUCRA, PT-AU was considered the most appropriate intervention by IKDC and Lachman test.

Conclusion

This study suggests that PT-AU may be the most appropriate graft for ACL reconstruction according to IKDC and Lachman test results.

Level of Evidence

Level I, network meta-analysis of randomized controlled trials.

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

Background:

Soft tissue quadriceps tendon (QT) autografts are increasingly popular as a primary graft choice for anterior cruciate ligament reconstruction (ACLR), but no study has compared superficial quadriceps activity levels and leg extension strength for QT versus bone–patellar tendon–bone (BTB) autografts.

Hypothesis:

Harvesting the central portion of the QT will alter rectus femoris (RF) firing patterns during maximum voluntary isometric contraction.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 34 patients (age range, 18-40 years) who underwent ACLR using a BTB (n = 17) or QT (n = 17) autograft at a single institution participated in this study. Participants, who had no neuromuscular injury or prior surgery on either lower extremity, were at least 1 year after ACLR, and were cleared for full activity. Postoperative rehabilitation protocols were consistent across participants. Synchronized electromyography (EMG) and isometric torque data were collected from participants in the seated position with the hips flexed to 90° and the knee at 60° of flexion. Participants were asked to extend their knees as quickly as possible and perform maximum voluntary isometric contraction for 3 seconds. A practice trial and 3 test trials were completed with 30-second rest intervals. Mixed (2 graft × 2 limb) analyses of variance were used to examine differences in average and peak torque values and RF/vastus lateralis (VL) and RF/vastus medialis (VM) ratios. Lysholm and International Knee Documentation Committee (IKDC) scores were compared between groups using unpaired t tests.

Results:

Significantly lower values were seen for the operative compared with the nonoperative extremity for average (P = .008; η² = 0.201) and peak torque (P < .0001; η² = 0.321), with no significant difference between graft types. Additionally, no significant differences in RF/VL or RF/VM ratios between limbs or graft types were observed.

Conclusion:

At 1 year after ACLR, QT and BTB autografts showed similar isometric strength deficits, with no differences in quadriceps muscle EMG ratios seen between the 2 graft types. The results support the use of a QT autograft for ACLR, as its graft harvest does not adversely affect quadriceps firing patterns in comparison with BTB graft harvest.

Magnetic resonance imaging of the quadriceps tendon autograft in anterior cruciate ligament reconstruction

BACKGROUND

Quadriceps tendon (QT) autograft is emerging as a popular technique for primary anterior cruciate ligament (ACL) reconstruction. Studies have shown that it has comparable outcomes to bone-patellar tendon-bone (BPTB) and hamstring tendon (HT) autografts while mitigating post-operative complications associated with these grafts.

PURPOSE

To provide a literature summary of the important pre- and post-operative magnetic resonance imaging (MRI) findings of the quadriceps tendon and pertinent postoperative complications associated with the QT harvest. Radiologists should be familiar with MR findings after autologous graft harvest of the quadriceps tendon for reconstruction of the ACL.

LEVEL OF EVIDENCE

Level IV.

Strength recovery after anterior cruciate ligament reconstruction with quadriceps tendon versus hamstring tendon autografts in soccer players: A randomized controlled trial

BACKGROUND

The comparison between HT and QT grafts in strength recovery and function after an ACLR is scarce in the literature.

METHODS

A total of 56 participants were enrolled in this randomized controlled trial and placed into two groups: HT or QT. The hamstring/quadriceps (H/Q) ratio was the primary end-point measured with a Genu-3 dynamometer. Peak torque, functional assessment (Lysholm knee scoring scale and Cincinnati Knee Rating System), and anteroposterior laxity (KT-2000™ arthrometer) were also assessed. An intention-to-treat analysis was performed.

RESULTS

The results of the H/Q ratio analysis of the participants over time revealed significant differences at 60, 180, and 300°/s at three, six, and 12months of follow-up (60°/s: F=5.3, p=0.005; 180°/s: F=5.5, p=0.004; 300°/s: F=5.1, p=0.005). Furthermore, they revealed significant differences at 60°/s, 180°/s, and 300°/s in the participants over time for peak torque in the extensor muscle strength at three and six months of follow-up, with higher values in the hamstring tendon group but not at 12months of follow-up. There were no significant differences in functional endpoints or arthrometer assessments at 24months of follow-up.

CONCLUSION

An ACLR with a QT graft showed similar functional results with a better isokinetic H/Q ratio compared to an ACLR with the HT at 12months of follow-up in soccer players. This higher H/Q ratio observed with the QT could be an advantage of this graft over the HT for an ACLR.

Anterior Cruciate Ligament Reconstruction Affects Tibiofemoral Joint Congruency During Dynamic Functional Movement

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) has been shown to alter kinematics, which may influence dynamic tibiofemoral joint congruency (a measure of how well the bone surfaces fit together). This may lead to abnormal loading of cartilage and joint degeneration. However, joint congruency after ACLR has never been investigated.

HYPOTHESES

The ACLR knee will be more congruent than the contralateral uninjured knee, and dynamic congruency will increase over time after ACLR. Side-to-side differences (SSD) in dynamic congruency will be related to cartilage contact location/area and subchondral bone curvatures.

STUDY DESIGN

Descriptive laboratory study.

METHODS

The authors examined 43 patients who underwent unilateral ACLR. At 6 months and 24 months after ACLR, patients performed downhill running on a treadmill while synchronized biplane radiographs were acquired at 150 images per second. Dynamic tibiofemoral kinematic values were determined by use of a validated volumetric model-based tracking process that matched patient-specific bone models, obtained from computed tomography, to biplane radiographs. Patient-specific cartilage models, obtained from magnetic resonance imaging, were registered to tracked bone models and used to calculate dynamic cartilage contact regions. Principle curvatures of the subchondral bone surfaces under each cartilage contact area were calculated to determine joint congruency. Repeated-measures analysis of variance was used to test the differences. Multiple linear regression was used to identify associations between SSD in congruency index, cartilage contact area, contact location, and global curvatures of femoral or tibial subchondral bone.

RESULTS

Lateral compartment congruency in the ACLR knee was greater than in the contralateral knee ( P < .001 at 6 months and P = .010 at 24 months). From 6 to 24 months after surgery, dynamic congruency decreased in the medial compartment ( P = .002) and increased in the lateral compartment ( P = .007) in the ACLR knee. In the lateral compartment, SSD in joint congruency was related to contact location and femur global curvature, and in the medial compartment, SSD in joint congruency was related to contact area.

CONCLUSION

ACLR appears to affect dynamic joint congruency. SSD in joint congruency was associated with changes in contact location, contact area, and femoral bony curvature.

CLINICAL RELEVANCE

Alterations in tibiofemoral contact location, contact area, and bone shape affect dynamic joint congruency, potentially contributing to long-term degeneration after ACLR.

Quadriceps Tendon Autograft in Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the current evidence to ascertain whether quadriceps tendon autograft (QT) is a viable option in anterior cruciate ligament reconstruction.

METHODS

A literature review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Cohort studies comparing QT with bone-patellar tendon-bone autograft (BPTB) or hamstring tendon autograft (HT) were included. Clinical outcomes were compared, with all statistical analyses performed using IBM SPSS Statistics for Windows, version 22.0, with P < .05 being considered statistically significant.

RESULTS

We identified 15 clinical trials with 1,910 patients. In all included studies, QT resulted in lower rates of anterior knee pain than BPTB. There was no difference in the rate of graft rupture between QT and BPTB or HT in any of the studies reporting this. One study found that QT resulted in greater knee stability than BPTB, and another study found increased stability compared with HT. One study found that QT resulted in improved functional outcomes compared with BPTB, and another found improved outcomes compared with HT, but one study found worse outcomes compared with BPTB.

CONCLUSIONS

Current literature suggests QT is a viable option in anterior cruciate ligament reconstruction, with published literature showing comparable knee stability, functional outcomes, donor-site morbidity, and rerupture rates compared with BPTB and HT.

LEVEL OF EVIDENCE

Level III, systematic review of Level I, II, and III studies.

Quadriceps tendon autograft for arthroscopic knee ligament reconstruction: use it now, use it often

Traditional bone-patellar tendon-bone and hamstring tendon ACL grafts are not without limitations. A growing body of anatomic, biomechanical and clinical data has demonstrated the utility of quadriceps tendon autograft in arthroscopic knee ligament reconstruction. The quadriceps tendon autograft provides a robust volume of tissue that can be reliably harvested, mitigating the likelihood of variably sized grafts and obviating the necessity of allograft augmentation. Modern, minimally invasive harvest techniques offer the advantages of low rates of donor site morbidity and residual extensor mechanism strength deficits. New data suggest that quadriceps tendon autograft may possess superior biomechanical characteristics when compared with bone-patella tendon-bone (BPTB) autograft. However, there have been very few direct, prospective comparisons between the clinical outcomes associated with quadriceps tendon autograft and other autograft options (eg, hamstring tendon and bone-patellar tendon-bone). Nevertheless, quadriceps tendon autograft should be one of the primary options in any knee surgeon's armamentarium.

Knee hyperextension does not adversely affect dynamic in vivo kinematics after anterior cruciate ligament reconstruction

PURPOSE

To evaluate the effect of knee hyperextension on dynamic in vivo kinematics after anterior cruciate ligament reconstruction (ACL-R).

METHODS

Forty-two patients underwent unilateral ACL-R. Twenty-four months after surgery, subjects performed level walking and downhill running on a treadmill while dynamic stereo radiographs were acquired at 100 (walking) and 150 Hz (running). Tibiofemoral motion was determined using a validated model-based tracking process, and tibiofemoral translations/rotations were calculated. The range of tibiofemoral motions from 0 to 10% of the gait cycle (heel strike to early stance phase) and side-to-side difference (SSD) were calculated. Maximum knee extension angle of ACL-reconstructed knees during walking was defined as active knee extension angle in each subject. Correlations between maximum knee extension angle and tibiofemoral kinematics data were evaluated using Spearman's rho (P < 0.05).

RESULTS

No significant correlation was observed between maximum knee extension angle and the range of anterior tibial translation during functional activities in the ACL-R knees. Maximum knee extension angle was weakly correlated with internal tibial rotation range in ACL-R knee during running (ρ = 0.376, P = 0.014); however, maximum extension angle was not correlated with SSD of internal tibial rotation. SSD of internal tibial rotation was -0.4° ± 1.9° (walking), -1.6° ± 3.1° (running), indicating ACL-R restored rotatory knee range of motion during functional movements.

CONCLUSION

Knee hyperextension was not significantly correlated with greater SSD of anterior translation and internal rotation. The clinical relevance is that knee hyperextension does not adversely affect kinematic outcomes after ACL-R and that physiologic knee hyperextension can be restored after ACL-R when knee hyperextension is present.

LEVEL OF EVIDENCE

III.

The evaluation of muscle recovery after anatomical single-bundle ACL reconstruction using a quadriceps autograft

PURPOSE

The purpose of this study was to reveal the degree of muscle recovery and report the clinical results of anatomical single-bundle ACL reconstruction using a quadriceps autograft.

METHODS

Twenty subjects undergoing anatomical single-bundle ACL reconstruction using a quadriceps autograft were included in this study. A 5-mm-wide, 8-cm-long graft, involving the entire layer of the quadriceps tendon, was harvested without bone block. The average graft diameter was 8.1 ± 1.4 mm. An initial tension of 30 N was applied. The femoral tunnel was created from the far-medial portal. Each femoral and tibial tunnel was created close to the antero-medial bundle insertion site. For the evaluation of muscle recovery (quadriceps and hamstring), a handheld dynamometer was used. The evaluation of muscle recovery was performed pre-operatively, and at 3, 6, 9, and 12 months after surgery. Muscle recovery data were calculated as a percentage of leg strength in the non-operated leg. Anterior tibial translation (ATT), pivot shift test, and IKDC score were evaluated.

RESULTS

The average quadriceps strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 90.5 ± 19, 67.8 ± 21.4, 84 ± 17.5, and 85.1 ± 12.6 %, respectively. The average hamstring strength pre-operatively, and at 3, 6, 9, and 12 months after ACL reconstruction was 99.5 ± 13.7, 78.7 ± 11.4, 90.5 ± 19, and 96.7 ± 13.8 %, respectively. ATT pre-operatively and at 12 months after surgery was 5.4 ± 1.3 and 1.0 ± 0.8 mm, respectively. No subjects exhibited positive pivot shift after surgery. Within 6 months following surgery, quadriceps hypotrophy was observed in all subjects. However, the hypotrophy had recovered at 12 months following surgery. No subjects complained of donor site pain after surgery.

CONCLUSION

Anatomical single-bundle ACL reconstruction using a quadriceps autograft resulted in equivalent level of muscle recovery and knee stability when compared with previously reported ACL reconstruction using hamstrings tendon with no donor site complications.

LEVEL OF EVIDENCE

Case controlled study, Level III.

Tensile properties of a split quadriceps graft for ACL reconstruction

PURPOSE

Anatomic double-bundle ACL reconstruction can be performed using different grafts, such as quadriceps tendon. Grafts can be split in either coronal or sagittal planes to approximate the two bundles of the native ACL, but it is unknown whether a difference exists in the graft tensile properties depending on splitting plane. The purpose of this study was to evaluate the tensile properties of split human quadriceps tendon-bone grafts.

METHODS

Twenty full-thickness quadriceps tendon-bone grafts were prepared to mimic grafts for double-bundle ACL reconstruction. Ten grafts were split in the sagittal plane, and ten were split in the coronal plane. Each graft underwent cyclic creep testing and load-to-failure testing to compare creep, ultimate load, ultimate elongation, stiffness, and tangent modulus between splitting planes. All parameters were compared between splitting groups (significance p < 0.05).

RESULTS

Lateral halves of grafts split in the sagittal plane exhibited a percent creep of 42.5 ± 12.4 %, ultimate load of 445 ± 210 N, ultimate elongation of 7.3 ± 1.9 mm, stiffness of 75.7 ± 19.9 N/mm, and tangent modulus of 174.0 ± 99.8 MPa. No differences were found between halves within split tendons or between splitting planes (n.s.).

CONCLUSIONS

Overall, splitting quadriceps tendon grafts for anatomic double-bundle ACL reconstruction results in similar tensile properties regardless of splitting plane. Surgeons can split quadriceps tendon in either splitting plane, but should take care to preserve fibres as much as possible. This study provides data that support the use of both coronal and sagittal splits of quadriceps tendons for anatomic double-bundle ACL reconstruction.

Quadriceps tendon autograft for anterior cruciate ligament reconstruction: a comprehensive review of current literature and systematic review of clinical results

PURPOSE

The autograft of choice for anterior cruciate ligament (ACL) reconstruction remains controversial. Recently, there has been an increase in interest in the quadriceps tendon as an autologous graft option for ACL reconstruction. The purposes of this study were to provide an in-depth review of quadriceps tendon anatomy, histology, and biomechanics and to synthesize reported clinical outcomes of ACL reconstructions using quadriceps tendon autografts. We hypothesize that (1) published studies on the anatomic, histologic, and biomechanical data regarding the quadriceps tendon support its use as a graft option for ACL reconstruction and (2) clinical outcomes of ACL reconstruction using quadriceps tendon autograft have similar clinical outcomes to bone-patellar tendon-bone autografts with less donor-site morbidity.

METHODS

We performed a comprehensive review of the literature regarding the anatomy, histology, and biomechanical studies of the quadriceps tendon, as well as a systematic review of clinical studies (Level of Evidence I-III) evaluating outcomes after ACL reconstruction using quadriceps tendon autograft. Stability outcomes, functional outcomes, range of motion, patient satisfaction, morbidity, and complications were comprised.

RESULTS

Fourteen studies were included in the review of clinical results, including 1,154 ACL reconstructions with quadriceps tendon autograft. Six studies directly compared quadriceps tendon autografts (n = 383) with bone-patellar tendon-bone autografts (n = 484). Stability outcomes (Lachman, pivot-shift, and instrumented laxity testing), functional outcomes (International Knee Documentation Committee and Lysholm scores), overall patient satisfaction, range of motion, and complications were similar between quadriceps tendon and other graft options. Less donor-site morbidity was seen in patients who underwent quadriceps tendon ACL reconstructions.

CONCLUSIONS

Use of the quadriceps tendon autograft for ACL reconstruction is supported by current orthopaedic literature. It is a safe, reproducible, and versatile graft that should be considered in future studies of ACL reconstruction.

LEVEL OF EVIDENCE

Level III, systematic review of Level I, II, and III studies.

Can joint contact dynamics be restored by anterior cruciate ligament reconstruction?

BACKGROUND

Rotational kinematics has become an important consideration after ACL reconstruction because of its possible influence on knee degeneration. However, it remains unknown whether ACL reconstruction can restore both rotational kinematics and normal joint contact patterns, especially during functional activities.

QUESTIONS/PURPOSES

We asked whether knee kinematics (tibial anterior translation and axial rotation) and joint contact mechanics (tibiofemoral sliding distance) would be restored by double-bundle (DB) or single-bundle (SB) reconstruction.

METHODS

We retrospectively studied 17 patients who underwent ACL reconstruction by the SB (n = 7) or DB (n = 10) procedure. We used dynamic stereo x-ray to capture biplane radiographic images of the knee during downhill treadmill running. Tibial anterior translation, axial rotation, and joint sliding distance in the medial and lateral compartments were compared between reconstructed and contralateral knees in both SB and DB groups.

RESULTS

We observed reduced anterior tibial translation and increased knee rotation in the reconstructed knees compared to the contralateral knees in both SB and DB groups. The mean joint sliding distance on the medial compartment was larger in the reconstructed knees than in the contralateral knees for both the SB group (9.5 ± 3.9 mm versus 7.5 ± 4.3 mm) and the DB group (11.1 ± 1.3 mm versus 7.9 ± 3.8 mm).

CONCLUSIONS

Neither ACL reconstruction procedure restored normal knee kinematics or medial joint sliding.

CLINICAL RELEVANCE

Further study is necessary to understand the clinical significance of abnormal joint contact, identify the responsible mechanisms, and optimize reconstruction procedures for restoring normal joint mechanics after ACL injury.

Anatomical evaluation of the rectus femoris tendon and its related structures

PURPOSE

The purpose of this study was to evaluate the anatomical structure of the quadriceps tendon in detail for use as an anterior cruciate ligament (ACL) graft tendon.

MATERIALS AND METHODS

Sixteen cadaveric knees with an average age of 78.8 were used. After careful dissection of skin and fascia, the muscle structure of each quadriceps was evaluated. In particular, the rectus femoris (RF) tendon was measured at its widest and narrowest width, the distance between widest or narrowest point and the proximal end of the patella, and the length.

RESULTS

The quadriceps tendon consisted of three layers. At the surface layer, the RF tendon existed mostly independently. The middle layer consisted of the vastus lateralis (VL) and medialis (VM) tendons. The deep layer consisted of the vastus intermedius (VI) tendon. The VL and VI tendons overlapped and were firmly connected, constituting the strength and size of the quadriceps. The narrowest width of the RF was 15.3 mm, and the narrowest point existed 4.8 mm proximal to the upper end of the patella. The average length of the RF was 27.3 cm.

CONCLUSION

If the RF tendon only is used as an ACL graft, surgeons should be cautious of the fact that the narrowest point of the RF tendon is located close to the patella. The entire quadriceps tendon is big enough to be used as an ACL graft. However, since the direction of the VL and VI tendons is different, the suitability of the quadriceps tendon as an ACL graft is questionable.