Anterior cruciate ligament reconstruction with use of autologous quadriceps tendon graft

Knee Extensor Mechanism Complications After Autograft Harvest in ACL Reconstruction: A Systematic Review and Meta-analysis

Background

Existing systematic reviews have sought to characterize the relative donor-site morbidity of bone-patellar tendon-bone (BTB) and quadriceps tendon (QT) grafts after anterior cruciate ligament reconstruction (ACLR). However, no studies have reported the pooled proportions of patellar fractures and donor tendon ruptures across the body of literature.

Purpose

To estimate the proportion of patellar fractures, patellar tendon ruptures, and QT ruptures associated with BTB or QT autograft harvest during ACLR using published data.

Study Design

Systematic review; Level of evidence, 4.

Methods

A meta-analysis was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using 3 online databases (PubMed, Scopus, and Web of Science). A total of 800 manuscripts were included in the initial research of peer-reviewed articles in English that reported extensor mechanism complications associated with graft harvest in patients after ACLR. Pooled proportions of patellar fractures, patellar tendon ruptures, and QT ruptures were calculated for each graft type (BTB, QT) using a random-effects model for meta-analysis.

Results

A total of 28 studies were analyzed. The pooled proportion of patellar fractures was 0.57% (95% CI, 0.34%-0.91%) for the BTB harvest and 2.03% (95% CI, 0.78%-3.89%) for the QT harvest. The proportion of patellar tendon ruptures was 0.22% (95% CI, 0.14%-0.33%) after the BTB harvest, and the proportion of QT ruptures was 0.52% (95% CI, 0.06%-1.91%) after the QT harvest. The majority of included studies (16/28 [57.1%]) had an evidence level of 4.

Conclusion

Based on the current literature, the proportion of extensor mechanism complications after ACLR using either a BTB or a QT autograft is low, indicating that the extensor mechanism harvest remains a safe option. A higher proportion of patellar fractures was noted for QT grafts and a higher proportion of donor tendon ruptures was noted for QT grafts compared with BTB grafts.

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.

Different timing in allograft and autograft maturation after primary anterior cruciate ligament reconstruction does not influence the clinical outcome at mid-long-term follow-up

PURPOSE

The use of allografts in primary anterior cruciate ligament reconstruction (ACLR) is increasing although they are still supposed to be associated to greater risk of re-rupture due to a slower and less efficient graft maturation. The aim of this prospective randomized controlled study was to compare the graft maturation after ACLR with allograft and autograft by MRI at 6- and 12-month follow-up and integrate these data with the functional and clinical results observed at 6-, 12- and 60-month follow-up.

METHODS

Fifty patients with indication to primary ACLR were randomly and equally divided into hamstring autograft or allograft tendon groups. The graft maturation was measured at 6- and 12-month follow-up by the SNQ score and other radiological parameters on MRI scans. Clinical and functional recovery was evaluated by Lysholm score, Visual Analogues Scale, Tegner activity scale and modified Cincinnati knee rating system at 6, 12 and 60 months after surgery to estimate the predictive value of the radiological parameters for clinical outcomes. Return-to-sport (ACL-RSI) was measured 60 months after surgery.

RESULTS

Three patients had retear of the neo-ligament (two from Auto group and one from Allo group). All the clinical/functional parameters significantly improved over time, with no statistically significant difference between the groups. At 6 months, the SNQ value was significantly higher in the Auto than in the Allo group (12.9 vs 7.9, p = 0.038), but at 12 months they were comparable (9.8 vs 10.4). The 6-month SNQ values did not correlate with the clinical scores, whereas the 12-month SNQ values significantly correlated with the Cincinnati score, Lysholm score and Tegner activity scale collected at 60-month follow-up.

CONCLUSION

No clinical or functional differences have been found between the two treatment groups, supporting the suitability of using allograft in primary ACLR, when available. The results at MRI scans showed a different graft maturation trend in the two groups, with allografts being more reactive in the first 6 months. MRI together with the subjective evaluation allows to evaluate objectively the status of the neo-ligamentization process and therefore helps the surgeon to dictate the individual time for return-to-sport.

LEVEL OF EVIDENCE

Level I.

Morphological Evaluation of the Quadriceps Tendon Using Preoperative Ultrasound in Anterior Cruciate Ligament Reconstruction

BACKGROUND

An evaluation of quadriceps tendon (QT) morphology preoperatively is an important step when selecting an individually appropriate autograft for anterior cruciate ligament (ACL) reconstruction. However, to our knowledge, there are no studies that have assessed the morphology of the entire QT in an ACL-injured knee preoperatively using ultrasound.

PURPOSE

We aimed to investigate the morphological characteristics of the QT using preoperative ultrasound in ACL-injured knees.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 33 patients (mean age, 26.0 ± 11.5 years) with a diagnosed ACL tear undergoing primary ACL reconstruction were prospectively included. Using ultrasound, short-axis images of the QT were acquired in 10-mm increments from 30 to 100 mm proximal to the superior pole of the patella. The length of the QT was determined by 2 contiguous images that did and did not contain the rectus femoris muscle belly. The width of the superficial and narrowest parts of the QT, the thickness of the central and thickest parts of the QT, and the cross-sectional area at the central 10 mm of the superficial QT width were measured at each assessment location. The estimated intraoperative diameter of the QT autograft was calculated using a formula provided in a previous study.

RESULTS

There were no significant relationships between QT morphology and any of the demographic data collected. The length of the QT was less than 70 mm in 45.5% of patients (15/33). The width, thickness, cross-sectional area, and estimated intraoperative diameter of the QT autograft were significantly greater at 30 mm than at 70 mm proximal to the superior pole of the patella.

CONCLUSION

Preoperative ultrasound may identify a QT that is too small for an all-soft tissue autograft in ACL reconstruction. Furthermore, harvesting a QT with a fixed width may result in autografts that are smaller proximally than they are distally. Assessing the morphology of the QT preoperatively using ultrasound may help surgeons to adequately reconstruct the native length and diameter of the ACL with a QT autograft.

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.

Effect of Time on MRI Appearance of Graft After ACL Reconstruction: A Comparison of Autologous Hamstring and Quadriceps Tendon Grafts

Background:

After anterior cruciate ligament (ACL) reconstruction (ACLR), changes in the appearance of the ACL graft can be monitored using magnetic resonance imaging (MRI).

Purpose:

The purpose of this study was to evaluate and compare the MRI signal intensity (SI) of hamstring and quadriceps tendon grafts during the first postoperative year after ACLR. As a secondary aim, the relationship of SI to clinical and anatomic measurements was analyzed.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A total of 78 patients who underwent ACLR with an autologous graft were reviewed; 55 received hamstring grafts and 23 received quadriceps tendon grafts. At 3 and 9 months postoperatively, 3-T MRI was performed using a dedicated knee coil, and the median SI of the intra-articular ACL graft was measured on sagittal-plane images. Postoperative lateral radiographs were analyzed to determine medial and lateral posterior tibial slope (PTS). Side-to-side difference in anterior knee laxity between injured and uninjured limbs was measured at 6 and 12 months postoperatively.

Results:

The median SI of quadriceps grafts was significantly greater than hamstring grafts at 3 months after ACLR (P = .02). Between 3 and 9 months, the median SI of quadriceps grafts decreased (P < .001), while that of hamstring grafts did not significantly change (P = .55). The lateral PTS was significantly correlated with median SI measurements at 3 and 9 months such that greater lateral PTS values were associated with greater median SI. The side-to-side difference in anterior knee laxity decreased for the quadriceps group (P = .04) between 6 and 12 months but did not change for the hamstring group (P = .88).

Conclusion:

The median SI of quadriceps grafts significantly decreased on MRI between 3 and 9 months after ACLR, while the median SI of hamstring grafts did not significantly change. The change in MRI appearance of the quadriceps grafts was paralleled by a reduction in anterior knee laxity between 6 and 12 months after surgery. In the absence of standardized imaging techniques and imaging analysis methods, the role of MRI in determining graft maturation, and the implications for progression through rehabilitation to return to sport, remain uncertain.

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.

Two-year postoperative MRI appearances of anterior cruciate ligament hamstrings autografts are not correlated with functional outcomes, anterior laxity, or patient age

Aims

MRI has been suggested as an objective method of assessing anterior crucate ligament (ACL) graft “ligamentization” after reconstruction. It has been proposed that the MRI appearances could be used as an indicator of graft maturity and used as part of a return-to-sport assessment. The aim of this study was to evaluate the correlation between MRI graft signal and postoperative functional scores, anterior knee laxity, and patient age at operation.

Methods

A consecutive cohort of 149 patients who had undergone semitendinosus autograft ACL reconstruction, using femoral and tibial adjustable loop fixations, were evaluated retrospectively postoperatively at two years. All underwent MRI analysis of the ACL graft, performed using signal-to-noise quotient (SNQ) and the Howell score. Functional outcome scores (Lysholm, Tegner, International Knee Documentation Committee (IKDC) subjective, and IKDC objective) were obtained and all patients underwent instrumented side-to-side anterior laxity differential laxity testing.

Results

Two-year postoperative mean outcome scores were: Tegner 6.5 (2 to 10); Lysholm 89.8 (SD 10.4; 52 to 100); and IKDC subjective 86.8 (SD 11.8; 51 to 100). The objective IKDC score was 86% A (128 patients), 13% B (19 patients), and 1% C (two patients). Mean side-to-side anterior laxity difference (134 N force) was 0.6 mm (SD 1.8; -4.1 to 5.6). Mean graft SNQ was 2.0 (SD 3.5; -14 to 17). Graft Howell scores were I (61%, 91 patients), II (25%, 37 patients), III (13%, 19 patients), and IV (1%, two patients). There was no correlation between either Howell score or SNQ with instrumented anterior or Lysholm, Tegner, and IKDC scores, nor was any correlation found between patient age and ACL graft SNQ or Howell score.

Conclusion

The two-year postoperative MRI appearances of four-strand, semitendinosus ACL autografts (as measured by SNQ and Howell score) do not appear to have a relationship with postoperative functional scores, instrumented anterior laxity, or patient age at surgery. Other tools for analysis of graft maturity should be developed.

Cite this article: Bone Jt Open 2021;2(8):569–575.

Long-term Outcomes of Anterior Cruciate Ligament Reconstruction Using Quadriceps Tendon-Patellar Bone Autograft

Background:

To date, there have been few studies on the outcomes of anterior cruciate ligament reconstruction (ACLR) using quadriceps tendon–patellar bone (QTPB) autograft.

Purpose:

To evaluate the long-term clinical outcomes of ACLR using QTPB autograft.

Study Design:

Case series; Level of evidence, 4.

Methods:

We retrospectively reviewed 139 patients who underwent primary ACLR with QTPB autografts and had at least 7 years of postoperative follow-up data. Instability, clinical scores, donor-site morbidity, radiographic progression of osteoarthritis, and any associated complications were assessed.

Results:

The proportion of knees classified as grade >1 on the anterior drawer, Lachman, and pivot-shift tests decreased significantly postsurgically (from 47.4% to 5.0%, 48.9% to 4.3%, and 53.3% to 5.0%, respectively; P < .001 for all). The mean clinical scores at the final follow-up were 89.8, 81.0, and 4.4 for the Lysholm, International Knee Documentation Committee, and Tegner Activity Scale, respectively. The results of the Cybex II dynamometer isokinetic test showed decreases in flexion and extension strength at both 60° and 180° per second, which persisted until the final follow-up visit. About one-fifth (19.4%) of the patients had osteoarthritis (Kellgren-Lawrence grade ≥1) before surgery, which increased to 33.8% at the final follow-up. The overall complication rate was 23.2%, and about one-third of the patients who experienced complications underwent revision surgery as a result of graft rupture and residual instability.

Conclusion:

In the current study, ACLR using QTPB autograft provided satisfactory long-term clinical results, with acceptable rates of complication and donor-site morbidity.

Aperture and Suspensory Fixation Equally Efficacious for Quadriceps Tendon Graft Fixation in Primary ACL Reconstruction: A Systematic Review

This review is aimed to compare suspensory and aperture quadriceps tendon autograft femoral and tibial fixations in primary anterior cruciate ligament reconstruction (ACL-R), and the clinical outcomes and complication profiles of each fixation method. Greater understanding of the optimal graft fixation technique for quadriceps tendon (QT) autografts may assist surgeons in improving outcomes after ACL-R. PubMed, Embase, and Medline were searched from database inception to September 2017, and again to July 2018, and identified 3,670 articles, 21 studies of which satisfied inclusion/exclusion criteria. Across included studies, 1,155 QT ACL-R patients (mean age, 28.7 years [range, 15-59 years], with mean postoperative follow-up of 36.1 months [range, 3.4-120 months]), were analyzed. Suspensory fixation on both sides demonstrated a higher percentage of patients (81.7%) achieving the highest rating of "A or B" on the International Knee Documentation Committee (IKDC) knee ligament examination form compared with aperture fixation on both sides (67.7%). Moreover, suspensory fixation had a lower side-to-side difference in anterior laxity (1.6 mm) when compared with aperture fixation (2.3 mm). Among studies which reported graft failure, all of which employed aperture fixation, the rate was 3.2%. Across available data, primary ACL-R using QT grafts appears to have successful short-term outcomes with a short-term graft failure rate of 3% independent of fixation method. While there is limited data regarding the comparison of aperture and suspensory soft-tissue quadriceps tendon (SQT) fixation in ACL-R, the findings of this systematic review suggest that suspensory fixation and aperture fixation in both the femoral and tibial tunnels are equally efficacious based on clinical outcome data on IKDC grade and measured laxity. This is a level IV, systematic review study.

All inside full thickness quadriceps tendon ACL reconstruction: Long term follow up results

Purpose

The aim of this study is to evaluate results of anterior cruciate ligament reconstruction (ACL) using an All-Inside Full Thickness Quadriceps Reconstruction technique at 5 years follow up.

Methods

This is a Retrospective cohort study of patients undergoing ACL reconstruction. Inclusion criteria for this report were isolated primary ACL reconstructions without chondral lesions (Grade III/IV Outerbridge), using autologous full-thickness quadriceps tendon (FQT) graft with bone block, with an “all-inside” technique. Functional scales of Lysholm, IKDC, Tegner and objective results of side to side difference (KT1000) were used for this evaluation. Additionally, complications and comorbidities were also analyzed.

Results

Two hundred and ninety-one ACL reconstructions were retrospectively reviewed at 5 years postoperatively; 268 (92.1%) were men and 23 (7.90%) women. Lysholm Score improved from 64 (SD = 6.09) to 91 (SD = 6.05) points average. IKDC showed 59.79%, excellent and 3.4% good results. Arthrometric analysis showed that 259 knees (89%) had a difference of less than 3 mm. Median pre-injury Tegner score was 9 (Range 4–10), while final median Tegner activity level at 5 years was 8 (Range 4–10). Among comorbidities, 5.15% of the patients presented anterior knee pain. No visualization difficulties or significant hematomas were found.

Conclusion

Use of all inside FQT for ACL reconstruction in a young, high demand sports population, present at 5 years, good to excellent results, functionally and objectively, with low rates of complications and comorbidities.

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.

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

BACKGROUND

Comprehensive studies evaluating quadriceps tendon (QT) autograft for anterior cruciate ligament (ACL) reconstruction are lacking. The optimal choice of graft between bone-patellar tendon-bone (BPTB), hamstring tendon (HT), and QT is still debatable.

HYPOTHESIS

The current literature supports the use of QT as a strong autograft with good outcomes when used in ACL reconstruction.

STUDY DESIGN

Meta-analysis; Level of evidence, 2.

METHODS

A systematic search of the literature was performed in PubMed, MEDLINE, Cochrane, and Ovid databases to identify published articles on clinical studies relevant to ACL reconstruction with QT autograft and studies comparing QT autograft versus BPTB and HT autografts. The results of the eligible studies were analyzed in terms of instrumented laxity measurements, Lachman test, pivot-shift test, Lysholm score, objective and subjective International Knee Documentation committee (IKDC) scores, donor-site pain, and graft failure.

RESULTS

Twenty-seven clinical studies including 2856 patients with ACL reconstruction met the inclusion criteria. Comparison of 581 QT versus 514 BPTB autografts showed no significant differences in terms of instrumented mean side-to-side difference (P = .45), Lachman test (P = .76), pivot-shift test grade 0 (P = .23), pivot-shift test grade 0 or 1 (P = .85), mean Lysholm score (P = .1), mean subjective IKDC score (P = .36), or graft failure (P = .50). However, outcomes in favor of QT were found in terms of less donor-site pain (risk ratio for QT vs BPTB groups, 0.25; 95% CI, 0.18-0.36; P < .00001). Comparison of 181 QT versus 176 HT autografts showed no significant differences in terms of instrumented mean side-to-side difference (P = .75), Lachman test (P = .41), pivot-shift test grade 0 (P = .53), Lysholm score less than 84 (P = .53), mean subjective IKDC score (P = .13), donor-site pain (P = .40), or graft failure (P = .46). However, outcomes in favor of QT were found in terms of mean Lysholm score (mean difference between QT and HT groups, 3.81; 95% CI, 0.45-7.17; P = .03).

CONCLUSION

QT autograft had comparable clinical and functional outcomes and graft survival rate compared with BPTB and HT autografts. However, QT autograft showed significantly less harvest site pain compared with BPTB autograft and better functional outcome scores compared with HT autograft.

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.

Quadriceps Tendon Graft Anatomy in the Skeletally Immature Patient

Background:

The quadriceps tendon (QT) is increasingly considered for primary and revision anterior cruciate ligament reconstruction in skeletally immature patients, as it may be harvested as a purely soft tissue graft with considerable tissue volume. Because of distinct rectus tendon (RT) separation from the QT complex, the potential for RT retraction exists and could lead to QT weakness after QT graft harvest.

Purpose:

To describe the anatomy of the pediatric QT and clarify decussation of the RT and QT to avoid the risk of delayed RT retraction and QT weakness after QT graft harvest.

Study Design:

Descriptive epidemiology study.

Methods:

Nine cadaveric knee specimens (aged 4-11 years) underwent gross dissection. Coronal-plane width and depth of the QT were measured at intervals proximal to the superior pole of the patella at distances of 0.0, 0.5, 1.0, and 1.5 times the length of the patella. The distance was measured from the superior patellar pole to the point of RT separation from the remainder of the deeper/posterior QT.

Results:

The median patellar length was 28 mm (interquartile range, 26-37 mm). The coronal-plane width of the QT was larger superficially/anteriorly when closest to the patella but wider when measured deeper/posteriorly as the tendon extended proximally. The median distance between the superior pole of the patella and RT separation from the QT was 0.95 times the patellar length. The distance to widening of the deeper/posterior aspect of the QT was 1.14 times the patellar length proximal to the patella.

Conclusion:

The RT begins a distinct separation from the QT above the superior pole of the patella at a median of 0.95 times the patellar length in skeletally immature specimens. The deeper/posterior aspect of the QT begins to increase in coronal-plane width proximally after a distance of 1.14 times the patellar length above the knee, while the superficial/anterior aspect of the tendon continues to narrow. Awareness of the separation of the RT from the QT, and the coronal-plane width variation aspects of the QT proximally, is important for surgeons utilizing the QT as a graft to avoid inadvertent release of the RT from the rest of the QT complex.

Assessment of Anterior Cruciate Ligament Graft Maturity With Conventional Magnetic Resonance Imaging: A Systematic Literature Review

Background:

Magnetic resonance imaging (MRI) signal intensity (SI) measurements are being used increasingly in both clinical and research studies to assess the maturity of anterior cruciate ligament (ACL) grafts in humans. However, SI in conventional MRI with weighted images is a nonquantitative measure dependent on hardware and software.

Purpose:

To conduct a systematic review of studies that have used MRI SI as a proxy for ACL graft maturity and to identify potential confounding factors in assessing the ACL graft in conventional MRI studies.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was conducted by searching the MEDLINE/PubMed, Scopus, and Cochrane Library electronic databases according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify studies that examined the healing of the intra-articular portion of the ACL graft by assessing SI on MRIs.

Results:

A total of 34 studies were selected for inclusion in this systematic review. The MRI acquisition techniques and methods to evaluate the ACL graft SI differed greatly across the studies. No agreement was found regarding the time frames of SI changes in MRI reflecting normal healing of the ACL tendon graft, and the graft SI and clinical outcomes after ACL reconstruction were found to be poorly correlated.

Conclusion:

The MRI acquisition and evaluation methods used to assess ACL grafts are very heterogeneous, impeding comparisons of SI between successive scans and between independent studies. Therefore, quantitative MRI-based biomarkers of ACL graft healing are greatly needed to guide the appropriate time of returning to sports after ACL reconstruction.

Comparison of Short-term Biodex Results After Anatomic Anterior Cruciate Ligament Reconstruction Among 3 Autografts

Background:

An individualized approach to anterior cruciate ligament reconstruction (ACLR) typically includes criteria-based postoperative rehabilitation. However, recent literature has suggested residual quadriceps weakness up to 12 months after ACLR, especially with a quadriceps tendon (QT) autograft.

Hypothesis:

The QT would have poorer quadriceps strength symmetry at 5 to 8 months compared with the hamstring tendon (HS) and patellar tendon (BPTB), but there would be no significant difference at 9 to 15 months among all 3 groups.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

Patients who underwent anatomic primary ACLR with an autograft were reviewed retrospectively. Isometric quadriceps and hamstring strength measurements were obtained clinically at 5 to 8 months and 9 to 15 months postoperatively. Return-to-running and return-to-play criteria included greater than 80% and 90% quadriceps strength symmetry, respectively.

Results:

A total of 73 patients with 5- to 8-month follow-up were identified, and 52 patients had 9- to 15-month data. The QT group had a significantly lower quadriceps index at 5 to 8 months (69.5 ± 17.4) compared with the BPTB (82.8 ± 14.6; P = .014) and the HS (86.0 ± 18.6; P = .001) groups. More patients with an BPTB autograft met criteria for return to running and return to play (60% and 47%, respectively) compared with the QT group (26% and 13%, respectively) at 5 to 8 months. Given the sample sizes available, we observed no significant difference in the quadriceps index and return-to-play and return-to-running criteria at 9 to 15 months among those undergoing ACLR with a QT, BPTB, or HS graft.

Conclusion:

Patients undergoing ACLR with a QT graft demonstrated clinically meaningful quadriceps asymmetry at 5 to 8 months and 9 to 15 months postoperatively. Additionally, fewer patients in the QT group met criteria for return to play and running at 5 to 8 months than the BPTB and HS groups. These data suggest that a longer time to return to play and specific rehabilitation protocols that emphasize quadriceps strengthening may be necessary because of residual quadriceps weakness after ACLR with a QT graft.

Patellar Fractures After the Harvest of a Quadriceps Tendon Autograft With a Bone Block: A Case Series

Background

The quadriceps tendon is a versatile graft option, and the clinical implications of a quadriceps tendon harvest need to be further defined.

Purpose

To review surgical considerations for the safe harvest of a quadriceps tendon autograft for anterior cruciate ligament (ACL) reconstruction, with a focus on the risk of patellar fractures.

Study Design

Case series; Level of evidence, 4.

Methods

A series of 57 patients underwent ACL reconstruction with a quadriceps tendon autograft with a patellar bone block from March 2011 to December 2012 at a single institution. Patients who sustained a patellar fracture were identified. The clinical course for each patient was reviewed with International Knee Documentation Committee (IKDC) subjective knee form scores through 2-year follow-up.

Results

The incidence of patellar fractures was 3.5% intraoperatively and 8.8% at 2 years. This included 2 intraoperative fractures, 1 fracture during strength testing, and 2 occult fractures detected on computed tomography (CT) performed 6 months postoperatively for research purposes in asymptomatic participants. For the 5 patients with a patellar fracture with 24-month follow-up, the IKDC scores were 91.95, 91.95, 100.00, 100.00, and 64.37.

Conclusion

Careful consideration of the quadriceps tendon and patellar anatomy is needed to safely harvest the bone plug from the superior pole of the patella. The consequences of a quadriceps tendon autograft harvest, specifically with regard to the risks associated with fractures of the patella during the harvest, demand full consideration. Postoperative imaging with CT may identify abnormalities in patients who are otherwise asymptomatic.

Ankle Lateral Ligament Augmentation Versus the Modified Broström-Gould Procedure: A 5-Year Randomized Controlled Trial

BACKGROUND

"Ankle sprain" is a common injury, and >20% of patients may develop chronic instability for which surgery is indicated. The modified Broström-Gould (MBG) procedure remains the gold standard; however, there are a number of relative contraindications to this procedure, and the longer-term outcomes after the MBG have been questioned. An alternative procedure is augmentation of a primary repair with a ligament augmentation reconstruction system (LARS).

PURPOSE

To conduct a randomized controlled trial testing the null-hypothesis that there is no difference in patient scored outcomes and activity levels, between patients undergoing a MBG procedure compared with those undergoing a primary repair with LARS augmentation, for lateral ligament instability of the ankle.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients who satisfied the inclusion criteria were invited to take part in the study. Patients were randomly allocated to undergo the LARS or MBG procedure. Both groups followed similar postoperative rehabilitation. Patients completed the Foot and Ankle Outcome Score (FAOS) before surgery and then at 1, 2, and 5 years after surgery. Tegner activity scores were recorded at 5years. The scores in the 2 groups were compared via statistical analysis ( P < .05).

RESULTS

Of the 50 patients satisfying the inclusion criteria, 47 agreed to take part in the study. Twenty-two were randomized to the LARS group and 25 to the MBG group. At 5 years, follow-up data were complete for 20 patients in the LARS group and 21 in the MBG. There were 2 failures in the MBG group and 0 in the LARS group. The LARS group had significantly better improvement in total FAOS at 1 year (mean ± SD, 92.4 ± 2.5 vs 78.2 ± 3.4, P = .005), 2 years (94.0 ± 3.0 vs 78.0 ± 5.2, P = .003), and 5 years (93.7 ± 6.0 vs 75.1 ± 5.5, P = .002) after surgery. The 5-year Tegner activity scores were higher in the LARS group (8.25 ± 1.1 vs 7.2 ± 0.9, P = .03).

CONCLUSION

Among physically active patients with chronic lateral ligament instability, primary repair combined with LARS results in better total FAOS at 5-year follow-up and higher Tegner activity scores as compared with the MBG procedure.

REGISTRATION

ACTRN12618000906257 (Australia New Zealand Clinical Trial Registry).

No difference between full thickness and partial thickness quadriceps tendon autografts in anterior cruciate ligament reconstruction: a systematic review

PURPOSE

The purpose of this review was to compare outcomes and complication profiles of anterior cruciate ligament reconstruction (ACL-R) between full thickness (FT-Q) and partial thickness (PT-Q) quadriceps tendon (QT) autografts.

METHODS

As per PRISMA guidelines, PubMed, EMBASE, and MEDLINE were searched in September 2017 for English language, human studies of all levels of evidence on patients undergoing primary ACL-R with FT-Q or PT-Q. This search was repeated in March 2018 to capture additional articles. Data regarding postoperative outcomes and complications were abstracted. Due to heterogeneous reporting, data were not combined in meta-analysis and were summarized descriptively.

RESULTS

Upon screening 3670 titles, 18 studies satisfied inclusion/exclusion criteria. The second search identified an additional two studies for a total of 20 studies (50% case-control, 50% case series). These studies examined 1212 patients (1219 knees) of mean age 29.8 years (range 15-59) followed a mean of 42.2 months (range 12-120). FT-Q and PT-Q autografts were used in eight studies (50.5% of knees), and thirteen studies (49.5% of knees), respectively. Only one study directly compared FT-Q to PT-Q. Instrumented laxity was less than 3 mm in 74.8 and 72.4% of the FT-Q and PT-Q groups, respectively. Postoperative IKDC Subjective Knee Form scores were similar between the FT-Q (82.5) and PT-Q (82.1) groups. Postoperative quadriceps strength, measured as a percentage of the contralateral side, were similar in the FT-Q (89.5%) and PT-Q (85.1%) groups. Graft failure rates for the FT-Q and PT-Q groups were 3.7 and 3.0%, respectively.

CONCLUSION

Across the 20 studies included in this review, there appeared to be no difference in outcomes or complications between either FT-Q or PT-Q in primary ACL-R. Moreover, primary ACL-R using QT autografts appears to have successful outcomes with a low rate of graft failure, irrespective of tendon thickness. While further comparative studies are needed to better delineate the optimal thickness of quadriceps tendon for primary ACL-R, these data suggest that, in primary ACL-R, either FT-Q or PT-Q is efficacious and, in the clinical setting, surgeons may be justified in using either graft thickness.

LEVEL OF EVIDENCE

IV, Systematic Review of Level III and IV studies.

The Quad Link Technique for an All-Soft-Tissue Quadriceps Graft in Minimally Invasive, All-Inside Anterior Cruciate Ligament Reconstruction

The quadriceps tendon autograft has become an attractive option for anterior cruciate ligament reconstruction (ACLR) because of its robust size and versatility as a graft. Emerging literature has shown impressive biomechanical viability and promising clinical outcomes. The substantial size of a quadriceps graft and the shorter graft requirement of the all-inside approach obviate the need to harvest a bone plug for supplemental graft length and allow the use of an all-soft-tissue graft. The recent development of sophisticated harvest tools has mitigated prior issues reported with quadriceps tendon harvest. Quadriceps graft harvest is now less technically challenging, more reproducible, and can be done through a minimally invasive incision. However, an optimal technique for attachment of the adjustable loop suspensory fixation devices to an all-soft-tissue quadriceps tendon graft has yet to be established. We describe our method for quadriceps tendon harvest and present the Quad Link technique for attachment of adjustable loop suspensory fixation devices to a quadriceps graft for ACLR.

Anterior cruciate ligament reconstruction with quadriceps tendon-patellar bone allograft: matched case control study

Background

Quadriceps tendon-patellar bone (QTPB) autograft is an excellent graft option with good clinical outcome. Use of QTPB autografts have increased because they minimize donor-site morbidity including anterior knee pain, while providing adequate mechanical strength. Although, there were many clinical results about allografts that used in anterior cruciate ligament (ACL) reconstruction, it have never been reported about the clinical outcome of ACL reconstruction with QTPB allograft.

The purpose of this study is to evaluate the clinical outcome of ACL reconstruction with QTPB allograft and to compare with QTPB autograft. We hypothesized that ACL reconstruction with QTPB allograft had good functional outcomes and stability and no significant difference compared to the ACL reconstruction with QTPB autograft.

Methods

From February 2009 to January 2014, 213 cases who received ACL reconstruction with QTPB grafts were included. Forty-five patients who received ACL reconstruction with QTPB allograft were individually matched in age, sex, direction of the injured knee and body mass index (BMI) to a control group of 45 patients who received QTPB autograft. Clinical results were evaluated using International Knee Documentation Committee (IKDC) score, Lysholm score, Tegner scale, Knee injury and Osteoarthritis Outcome Score (KOOS) and ligament laxity. An average follow-up time was 31.2 months.

Results

The functional scores and ligament laxity improved from initial to the last visit in those with ACL reconstruction with QTPB allograft (p < 0.05). No significant statistical difference was found in clinical outcomes and complications including re-rupture between the QTPB allograft and autograft groups (p > 0.05). Laxity using anterior drawer test, Lachman test and KT-2000 showed no significant difference. No significant difference was found between the two groups in quadriceps peak extension torque, except at 60° per second at 6 months.

Conclusion

QTPB allograft achieved good clinical outcome with no difference compared with QTPB autograft. QTPB allograft for ACL reconstruction is promising alternative to selected and compliant patients. Long-term follow-up needs to further evaluate the clinical outcomes and complications including re-rupture rate.

There is no difference between quadriceps- and hamstring tendon autografts in primary anterior cruciate ligament reconstruction: a 2-year patient-reported outcome study

PURPOSE

Graft choice for anterior cruciate ligament (ACL) reconstruction is crucial, however the optimal graft source remains a topic of controversy. The purpose of this study is to compare subjective and functional patient-reported outcomes (PRO) after single-bundle ACL reconstruction using quadriceps tendon (QT) or hamstring tendon (HT) autografts for single-bundle ACL reconstruction. We hypothesize that there is no difference in patient-reported functional outcomes after ACL reconstruction using either HT- or QT autograft.

METHODS

All data were extracted from a prospectively collected ACL registry. A total of 80 patients with at least 2-year follow-up were included in this study. A total of 40 patients with primary ACL reconstruction using a QT autograft harvested via a minimally invasive technique were matched by sex, age and pre-injury Tegner and Lysholm score to 40 patients who received HT autografts. Subjective and functional PRO scores including Lysholm score, Tegner activity level and visual analogue scale for pain were obtained at 6, 12 and 24 months after index surgery.

RESULTS

No significant difference between the QT and the HT group was seen at any follow-up in regard to any of the PRO scores for function or pain. 24 months post-surgery the mean Tegner activity score of the HT group was significantly (p = 0.04) lower compared to the pre-injury status. At final follow-up, 27 patients (67.5%) in the QT group and 32 patients (80.0%) in the HT returned to their pre-injury activity level (n.s.). A total of 37 patients (92.5%) of the QT cohort and 35 patients (87.5%) of the HT cohort reported "good" or "excellent" results according to the Lysholm score (n.s.). "No pain" or "slight pain" during severe exertion was reported by 33 patients (82.5%) with QT autograft and 28 patients (82.4%) with HT autograft (n.s.).

CONCLUSION

There is no significant difference between PRO 2 years post-operative using either QT or HT autografts. Both QT and HT grafts show acceptable and comparable PRO scores making the QT a reliable graft alternative to HT for primary ACL reconstruction.

LEVEL OF EVIDENCE

III.

New insight in the architecture of the quadriceps tendon

BACKGROUND

Published data regarding the structure of the quadriceps tendon are diverse. Dissection of the quadriceps muscle group revealed that beside the rectus femoris, vastus lateralis, vastus intermedius and vastus medialis a fifth muscle component- named the tensor vastus intermedius consistently fused into quadriceps tendon. It can be hypothesized that all these elements of the extensor apparatus of the knee joint must also be represented in the quadriceps tendon. This study investigated the multi-layered quadriceps tendon with special emphasis on all components of the quadriceps muscle group including the newly discovered tensor vastus intermedius.

METHODS

Ten cadaveric lower limbs were dissected. All muscle bellies of the extensor apparatus of the knee joint were identified and traced distally until they merged into the quadriceps tendon. Connections between the different aponeurotic layers of each muscle were studied from origin to insertion. The fusing points of each layer were marked. Their distance to the patella and the distances between the fusing points were measured.

RESULTS

Six elements of the quadriceps muscle group form a tri-laminar structure of the quadriceps tendon. The intermediate layer could be further sub-divided. The elements of the quadriceps tendon are 1. lateral aponeurosis of the vastus intermedius, 2. deep and 3. superficial medial aponeurosis of the vastus intermedius, 4. vastus lateralis, 5. tensor vastus intermedius and 6. rectus femoris. Even with differences in fiber direction - these elements join each other a certain distance proximal to the patella. All elements were fused over a region measuring 13 to 90 mm proximal to the patella. Lateral parts of the vastus intermedius formed the deepest layer of the quadriceps tendon. The superficial and deep layer of the medial vastus intermedius aponeurosis fused 56 mm (range, 30 to 90 mm) and 33 mm (range, 13 to 53 mm) above the patella with the aponeurosis of the tensor vastus intermedius and vastus lateralis respectively. Together they built the two-layered intermediate layer of the quadriceps tendon. The tendon of the rectus femoris forms the superficial layer. The vastus medialis inserts medially in all layers of the quadriceps tendon. Fibers of the lateral muscle components were oriented towards the medial, and fibers of the medial muscle components were oriented towards the lateral femoral condyle.

CONCLUSIONS

The three-layered quadriceps tendon is formed by six elements. These are 1. lateral aponeurosis of the vastus intermedius, 2. deep and 3. superficial medial aponeurosis of the vastus intermedius, 4. vastus lateralis, 5. tensor vastus intermedius and 6. rectus femoris. These elements of the extensor apparatus join each other proximal to the patella in a complex onion-like architecture. Its two-layered intermediate layer shows variable fusions points. The vastus medialis contributes to the quadriceps tendon with its medial insertion into all layers of the quadriceps tendon.

Outcomes of Anatomic Anterior Cruciate Ligament Reconstruction: Bone-Quadriceps Tendon Graft Versus Double-Bundle Hamstring Tendon Graft

BACKGROUND

The choice of graft type is an important factor to the outcome of anterior cruciate ligament (ACL) reconstruction.

PURPOSE

To compare knee joint stability and functional outcomes of anatomic ACL reconstruction with double-bundle hamstring tendon (DBHT) and bone-quadriceps tendon (BQT) autografts.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Ninety-six patients underwent ACL reconstruction with either DBHT (hamstring group) or BQT autograft (quadriceps group). Each group included 48 patients who were retrospectively matched on the basis of age, sex, and body mass index; there were no statistically significant differences between the 2 groups (all P > .05). All patients had a minimum follow-up of 2 years. Outcome evaluations included the manual laxity test, International Knee Documentation Committee subjective evaluation, Tegner activity score, modified Lysholm score, anterior knee pain questionnaire, KT-2000 arthrometer side-to-side difference, Cybex II isokinetic testing, and tunnel position evaluation by quadrant method.

RESULTS

Manual laxity test results were significantly improved in both groups after surgery (all P < .05). The maximum KT-2000 arthrometer side-to-side difference improved from 4.0 to 1.9 mm in the hamstring group and 3.9 to 2.1 mm in the quadriceps group (P = .65). Modified Lysholm scores in the hamstring and quadriceps groups improved from 69.4 and 70.2 to 88.4 and 92.1 (P = .30), and International Knee Documentation Committee subjective evaluation scores improved from 56.0 and 60.3 to 77.9 and 80.2 (P = .37), respectively. Tegner activity scores for the hamstring and quadriceps groups were 4.7 and 4.6 preoperatively and 4.6 and 4.7 (P = .80) at final follow-up, respectively. There were no between-group differences on postoperative anterior knee pain (P > .05 for all questionnaire categories), nor were there differences in recovered extensor muscle strength during isokinetic testing (82.9% vs 81.0% at 60 deg/s, P = .71; 85.1% vs 83.8% at 180 deg/s, P = .81). However, flexor muscle strength recovery was better in the quadriceps group (86.6% vs 92.2% at 60 deg/s, P = .22; 87.1% vs 99.6% at 180 deg/s, P = .01). There were no significant differences in tunnel positioning between the 2 groups (all P > .05).

CONCLUSION

Anatomic ACL reconstruction with the BQT autograft showed similar knee stability and functional outcome scores when compared with the DBHT autograft. Additionally, better flexor muscle strength recovery was found in the quadriceps group, indicating a potential advantage of the BQT autograft in ACL reconstruction.

Height, weight, and age predict quadriceps tendon length and thickness in skeletally immature patients

BACKGROUND

Quadriceps tendon autografts have been used with success in adults and are becoming a popular graft option in pediatric patients because of size, decreased donor site morbidity, ease of harvest, and favorable biomechanical characteristics. However, little is known about the length and thickness of the quadriceps tendon in pediatric patients.

PURPOSE

This study aimed to determine whether quadriceps tendon length and thickness follow a predictable pattern of development based on height, weight, age, and body mass index in skeletally immature patients.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

The height, weight, age, and sex of 151 children between 4 and 16 years old were recorded. Ultrasound measurements of the length and thickness of bilateral quadriceps tendons were performed by a single technician and recorded for statistical analysis.

RESULTS

The average quadriceps tendon length and thickness were 6.87 ± 1.49 cm and 0.37 ± 0.12 cm, respectively. Tendon length averaged 3.89 cm at age 4 years and 7.98 cm at 16 years, whereas thickness averaged 0.24 cm at 4 years and 0.40 cm at 16 years of age. There was no significant difference in tendon length or thickness between males and females (P = .97). Tendon length and thickness increased significantly with age, weight, and height (P < .01 for all).

CONCLUSION

The quadriceps tendon is of sufficient length and thickness to be used as an autograft for pediatric patients. The size of the graft is predictable using the age, height, and weight of the patient. Graft length and thickness can be easily confirmed using ultrasound.

Biomechanical evaluation of anatomic single- and double-bundle anterior cruciate ligament reconstruction techniques using the quadriceps tendon

PURPOSE

Quadriceps tendon grafts have renewed interest for ACL reconstruction; however, biomechanical studies comparing anatomic single-bundle (SB) and double-bundle (DB) reconstruction techniques are rare. The purpose of this study was to compare the knee biomechanics in four different types of anatomic ACL reconstruction techniques, using the quadriceps tendon in a human cadaver.

METHODS

Four different tibial (T) and femoral (F) tunnel configurations, (a) DB-2F-2T, (b) DB-2F-1T, (c) SB-1F-1T and (d) DB-1F-2T, were used for ACL reconstruction using the split quadriceps tendon with patella bone. Ten cadaver knees were subjected to an 89 N anterior tibial load and combined 7 N m valgus and 5 N m internal torques. The anterior tibial translation (ATT) and in situ force were measured using a robotic system for the ACL-intact, ACL-deficient and ACL-reconstructed knees.

RESULTS

DB reconstructions mostly restored ATT to the intact ACL. The in situ forces under the anterior load in the DB reconstructions were similar to the intact ACL, but that of the SB reconstruction was different at 30°, 60° and 90° of flexion (P < 0.05). Under combined torques, the in situ force of the SB graft was less than that of intact ACL at 0°, 15° and 30° of knee flexion (P < 0.05), while that of the ACL DB reconstruction was similar to the intact ACL.

CONCLUSION

DB ACL reconstruction using quadriceps tendon can restore biomechanics of the knee to that of the intact ACL regardless of whether three or four tunnels are used, but SB reconstruction does not.

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.

Multirater agreement of the causes of anterior cruciate ligament reconstruction failure: a radiographic and video analysis of the MARS cohort

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction failure occurs in up to 10% of cases. Technical errors are considered the most common cause of graft failure despite the absence of validated studies. Limited data are available regarding the agreement among orthopaedic surgeons regarding the causes of primary ACL reconstruction failure and accuracy of graft tunnel placement.

HYPOTHESIS

Experienced knee surgeons have a high level of interobserver reliability in the agreement about the causes of primary ACL reconstruction failure, anatomic graft characteristics, and tunnel placement.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

Twenty cases of revision ACL reconstruction were randomly selected from the Multicenter ACL Revision Study (MARS) database. Each case included the patient's history, standardized radiographs, and a concise 30-second arthroscopic video taken at the time of revision demonstrating the graft remnant and location of the tunnel apertures. All 20 cases were reviewed by 10 MARS surgeons not involved with the primary surgery. Each surgeon completed a 2-part questionnaire dealing with each surgeon's training and practice, as well as the placement of the femoral and tibial tunnels, condition of the primary graft, and the surgeon's opinion as to the causes of graft failure. Interrater agreement was determined for each question with the kappa coefficient and the prevalence-adjusted, bias-adjusted kappa (PABAK).

RESULTS

The 10 reviewers have been in practice an average of 14 years and have performed at least 25 ACL reconstructions per year, and 9 were fellowship trained in sports medicine. There was wide variability in agreement among knee experts as to the specific causes of ACL graft failure. When participants were specifically asked about technical error as the cause for failure, interobserver agreement was only slight (PABAK = 0.26). There was fair overall agreement on ideal femoral tunnel placement (PABAK = 0.55) but only slight agreement on whether a femoral tunnel was too anterior (PABAK = 0.24) and fair agreement on whether it was too vertical (PABAK = 0.46). There was poor overall agreement for ideal tibial tunnel placement (PABAK = 0.17).

CONCLUSION

This study suggests that more objective criteria are needed to accurately determine the causes of primary ACL graft failure as well as the ideal femoral and tibial tunnel placement in patients undergoing revision ACL reconstruction.

Primary ankle ligament augmentation versus modified Brostrom-Gould procedure: a 2-year randomized controlled trial

BACKGROUND

More than 20% of patients develop chronic instability following appropriate management of an 'ankle sprain'. There is little research comparing surgical techniques. 'Anatomical' procedures, such as the modified Brostrom-Gould (MBG), are generally preferred. However, not all patients are suitable for this procedure. Augmentation of a primary repair using a synthetic ligament, such as the ligament augmentation reconstruction system (LARS), is another 'anatomic' option. Our objective was to compare the clinical outcome following the MBG with that following the LARS technique using a prospective randomized clinical trial.

METHODS

Patients who satisfied the study criteria were randomly allocated to undergo the LARS procedure or the MBG procedure. All patients followed a similar rehabilitation programme. Patients completed the foot and ankle outcome score (FAOS) before surgery, and then at 1 year and 2 years following surgery. Statistical analysis was used to compare the groups (P < 0.05).

RESULTS

Forty-one patients took part in the study, 21 were randomized to the LARS group and 20 to the MBG group. The LARS group had a significantly better improvement in the total FAOS at both 1 year (25.5 standard error (SE) 3.8 versus 16.0 SE 3.3) and 2 years (27.1 SE 4.5 versus 15.8 SE 4.9) post-surgery.

CONCLUSION

Primary repair combined with LARS results in better patient-scored clinical outcome, at 2 years post-surgery, than the MBG procedure. Although longer follow-up is required, the LARS procedure may be considered as an alternative, especially in those patients for whom the MBG is relatively contra-indicated.

Anterior Cruciate Ligament Reconstruction with Quadriceps Tendon Autograft: A Minimally Invasive Harvest Technique

Introduction

We describe a minimally invasive surgical technique for harvest of a quadriceps tendon autograft that reliably produces a graft suitable for anterior cruciate ligament (ACL) reconstruction while minimizing morbidity and complications classically associated with alternative autograft choices.

Step 1 Positioning

Position the patient supine on the operating room table.

Step 2 Marking of Landmarks

Palpate and mark soft-tissue and osseous landmarks on the involved extremity.

Step 3 Subcutaneous Dissection

Perform the incision and subcutaneous dissection.

Step 4 Graft Harvest

Harvest the graft.

Step 5 Graft Preparation

Prepare the graft.

Step 6 Closure

If a partial-thickness graft is harvested, no deep closure is needed.

Results

Since September of 2011, the quadriceps tendon has been our autograft of choice for ACL reconstruction.IndicationsContraindicationsPitfalls & Challenges.

Modified Transtibial Technique for Anterior Cruciate Ligament Reconstruction with Quadriceps Tendon Autograft

Introduction

The modified transtibial technique with quadriceps tendon autograft allows anatomic anterior cruciate ligament (ACL) reconstruction without tunnel widening and results in a stable and functional knee with a satisfactory clinical outcome.

Step 1 Prepare the Patient

Prepare the patient under spinal anesthesia with the usual arthroscopic setting.

Step 2 Arthroscopic Examination

Perform arthroscopic examination to confirm the ACL rupture and other intra-articular lesions.

Step 3 Harvest the Quadriceps Tendon

Harvest the central one-third of the quadriceps tendon strip with a proximal patellar bone block.

Step 4 Prepare the Quadriceps Tendon Graft

Prepare the quadriceps tendon graft to pass smoothly through the tunnels.

Step 5 Set the Tibial Tunnel Entry Point

Make a 3-cm longitudinal skin incision at the anteromedial aspect of the proximal part of the tibia.

Step 6 Create the Tibial Tunnel

Drill a 10-mm tibial tunnel.

Step 7 Target the Femoral Tunnel Starting Point

Aim the guide at the lateral bifurcate ridge on the medial wall of the lateral femoral condyle with the modified transtibial technique.

Step 8 Create the Femoral Tunnel

Drill a 10-mm femoral tunnel.

Step 9 Fix the Graft

Fix the graft with adequate tension.

Step 10 Postoperative Rehabilitation

Rehabilitate the patient step by step.

Results

In a study that compared fifty-two patients managed with a modified transtibial technique and another fifty-two patients managed with an anteromedial transportal technique, there were no significant differences in the clinical results in terms of manual laxity, arthrometric analysis, and subjective outcome.IndicationsContraindicationsPitfalls & Challenges.

Is quadriceps tendon a better graft choice than patellar tendon? a prospective randomized study

PURPOSE

The purpose of this randomized controlled study was to compare knee stability, kneeling pain, harvest site pain, sensitivity loss, and subjective clinical outcome after primary anterior cruciate ligament (ACL) reconstruction with either bone-patellar tendon-bone (BPTB) or quadriceps tendon-bone (QTB) autografts in a noninferiority study design.

METHODS

From 2005 to 2009, a total of 51 patients were included in the present study. Inclusion criteria were isolated ACL injuries in adults. Twenty-five patients were randomized to BPTB grafts and 26 to QTB grafts. An independent examiner performed follow-up evaluations 1 and 2 years postoperatively. Anteroposterior knee laxity was measured with a KT-1000 arthrometer (MEDmetric, San Diego, CA). Anterior knee pain was assessed clinically and by knee-walking ability. Knee Injury and Osteoarthritis Outcome Score (KOOS) and subjective International Knee Documentation Committee (IKDC) score were used for patient-evaluated outcome.

RESULTS

Anterior knee laxity was equal between the 2 groups with KT-1000 values of 1.1 ± 1.4 mm and 0.8 ± 1.7 mm standard deviation (SD) at follow-up in QTB and BPTB groups, respectively (P = .65), whereas positive pivot shift test results were seen less frequently (14% compared with 38%, respectively; P = .03). Anterior kneeling pain, evaluated by the knee walking ability test, was significantly less in the QTB group, with only 7% of patients grading knee walking as difficult or impossible compared with 34% in the BPTB group. At 1 and 2 years' follow-up, there was no difference between the 2 groups in subjective patient-evaluated outcome. The IKDC score was 75 ± 13 patients and 76 ± 16 SD at 1-year follow-up in QTB and BPTB groups, respectively (P = .78). At 2 years, 12 patients were lost to follow-up, resulting in 18 in the BPTB group and 21 in the QTB group.

CONCLUSIONS

The use of the QTB graft results in less kneeling pain, graft site pain, and sensitivity loss than seen with BPTB grafts; however, similar anterior knee stability and subjective outcomes are seen. The results of this study show that QTB is a viable option for ACL reconstruction.

LEVEL OF EVIDENCE

Level II, randomized controlled clinical trial.

"Central" quadriceps tendon harvest with patellar bone plug: surgical technique revisited

The objective of this article is to review the surgical technique for quadriceps tendon graft harvest while highlighting an additional technical note that has not been previously emphasized. The quadriceps tendon typically inserts eccentrically on the superior pole of the patella. By shifting the soft-tissue harvest to a location just off the medial edge of the tendon, the adjoining patellar bone plug will be centered on the superior pole of the patella, reducing the risk of an iatrogenic patellar fracture.

Outcomes for primary anterior cruciate reconstruction with the quadriceps autograft: a systematic review

PURPOSE

To determine the suitability of the quadriceps autograft in primary anterior cruciate ligament (ACL) reconstruction.

METHODS

A systematic review was undertaken to identify all clinical studies reporting on the use of the quadriceps tendon autograft in ACL reconstructions. Studies that reported on clinical and functional outcomes, morbidity and complications were selected.

RESULTS

Seventeen articles met our inclusion criteria with a total of 1,580 reconstructions studied. This included four comparative studies which compared the quadriceps tendon to either hamstring or patella tendon autografts. The quadriceps tendon autograft had clinical (Lachman, Pivot-shift testing) and functional outcomes (Lysholm and IKDC scores) similar to those reported for the patella tendon and hamstring grafts in the literature. Comparative studies also reported no significant difference between the grafts for any outcome measure.

CONCLUSIONS

The quadriceps tendon autograft is a promising alternative for primary ACL reconstructions with good outcomes and minimal donor site morbidity. Further studies are required, however, to determine whether the quadriceps graft is as good as or better than other autografts.

LEVEL OF EVIDENCE

IV.

Femoral tunnel malposition in ACL revision reconstruction

The Multicenter Anterior Cruciate Ligament (ACL) Revision Study (MARS) group was formed to study a large cohort of revision ACL reconstruction patients. The purpose of this subset analysis study of the MARS database is to describe specific details of femoral tunnel malposition and subsequent management strategies that surgeons chose in the revision setting. The design of this study is a case series. The multicenter MARS database is compiled from a questionnaire regarding 460 ACL reconstruction revision cases returned by 87 surgeons. This subset analysis described technical aspects and operative findings in specifically those cases in which femoral tunnel malposition was cited as the cause of primary ACL reconstruction failure. Of the 460 revisions included for study, 276 (60%) cases cited a specific "technical cause of failure." Femoral tunnel malposition was cited in 219 (47.6%) of 460 cases. Femoral tunnel malposition was cited as the only cause of failure in 117 cases (25.4%). Surgeons judged the femoral tunnel too vertical in 42 cases (35.9%), too anterior in 35 cases (29.9%), and too vertical and anterior in 31 cases (26.5%). Revision reconstruction involved the drilling of an entirely new femoral tunnel in 91 cases (82.1%). For primary reconstruction, autograft tissue was used in 82 cases (70.1%). For revision reconstruction, autograft tissue was used in 61 cases (52.1%) and allograft tissue in 56 cases (47.9%). Femoral tunnel malposition in primary ACL reconstruction was the most commonly cited reason for graft failure in this cohort. Graft selection is widely variable among surgeons.

Prospective analysis of failure rate and predictors of failure after anatomic anterior cruciate ligament reconstruction with allograft

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction is one of the most frequently performed orthopaedic procedures. Failures are a reality of surgery; to limit failures, we must first understand and quantify them.

PURPOSE

The purposes of this study were to determine the rate and factors associated with graft failure after anatomic ACL reconstruction performed with allograft.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

All consecutive subjects who underwent anatomic single- or double-bundle ACL reconstruction with allograft between January 2007 and December 2009 were included and followed clinically. Graft failure was defined as patient-reported instability, pathological laxity during the physical examination, or evidence of a failed graft on magnetic resonance imaging or during arthroscopy. Potential predictors of graft failure that were explored included subject age, sex, height, weight, body mass index, meniscus injury, and time of return to preinjury sports.

RESULTS

There were 206 subjects included in this study: 168 double-bundle and 38 single-bundle reconstructions. Overall, 27 (13%) subjects experienced graft failure. Twenty-three (13%) double-bundle subjects failed. The characteristics associated with double-bundle graft failure were younger age (19 vs 25 years, P < .001) and earlier return to sports (at 222 vs 267 days, P = .007). Four (11%) of the single-bundle subjects failed. The characteristics associated with single-bundle graft failure were younger age (19 vs 24 years, P = .049) and increased body mass (83 vs 65 kg, P = .031).

CONCLUSION

The overall graft failure rate after anatomic ACL reconstruction with allograft was 13%. Younger age, earlier return to sports, and a higher body weight were associated with graft failure.

Autografts commonly used in anterior cruciate ligament reconstruction

Anterior cruciate ligament reconstruction is among the most common orthopaedic procedures in the United States, with >200,000 performed annually. Much has been published regarding the use of autograft versus allograft. Bone-patellar tendon-bone is the most frequently used autograft, but hamstring and quadriceps tendon grafts are common alternatives. Each graft has distinct advantages and disadvantages, and selection is individualized. Fixation methods vary by graft type. Fixation resulting in a construct that is too rigid may restrict knee range of motion. Donor site morbidity must be considered, as well. Autograft harvest may result in anterior knee pain, kneeling pain, anterior knee numbness, muscle weakness, and patellar fracture. Appropriate graft selection is essential to optimize outcomes.

Anterior cruciate ligament reconstruction using quadriceps tendon autograft: intermediate-term outcome

PURPOSE

The purpose of this study was to compare the intermediate-term outcomes of anterior cruciate ligament (ACL) reconstruction by use of bone-patellar tendon-bone (BPTB), quadriceps tendon with a bone plug (BQT), and quadriceps tendon without a bone plug (QT).

METHODS

We evaluated 198 primary ACL reconstructions in 191 patients at a mean of 55.6 months postoperatively. Assessment included side-to-side comparison of range of motion, arthrometer values, presence of effusion, anterior knee pain, and numbness. Comparisons were made between QT and BQT patients and between men and women. The results were compared with data from 30 patients in a previous study who had undergone ACL reconstruction by the same surgeon (W.R.S.) with BPTB.

RESULTS

Range of motion averaged -3.2 degrees +/- 2.2 degrees of extension to 134.3 degrees +/- 10.2 degrees of flexion for the operative extremity compared with -3.6 degrees +/- 2.07 degrees to 134.2 degrees +/- 10.6 degrees for the contralateral extremity at final follow-up. KT-1000 manual maximum measurements (MEDmetric, San Diego, CA) of the operative extremity averaged 0.94 mm more than those of the normal contralateral knee. When compared with BPTB autograft, the quadriceps tendon autograft showed significantly better results, with less anterior knee pain (4.56% v 26.7%), less anterior numbness (1.5% v 53.3%), a higher percentage of arthrometer measurements showing a side-to-side difference of 0 to 3 mm (88% v 68%), and better extension (mean loss, 0.55 degrees v 2.77 degrees ). There was no significant difference between the 2 groups with regard to loss of flexion, Lachman test, pivot-shift test, presence of effusion, or number of failures.

CONCLUSIONS

Central quadriceps tendon autograft, QT or BQT, produces equivalent results when compared directly with BPTB autograft in arthroscopically assisted ACL reconstruction. There was no difference in results between men and women with a quadriceps tendon autograft, either with or without the use of a bone plug. ACL reconstruction using quadriceps tendon autograft is an effective surgical option that reduces donor-site morbidity.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Anterior cruciate ligament reconstruction: autogenous quadriceps tendon-bone compared with bone-patellar tendon-bone grafts at 2-year follow-up

PURPOSE

The purpose of this study was to evaluate and compare postoperative anterior knee pain, knee stability, and functional scores of an autogenous bone-patellar tendon-bone (BPTB) graft and a quadriceps tendon-bone (QTB) graft.

METHODS

A total of 48 patients--27 who had anterior cruciate ligament (ACL) reconstruction by use of an autogenous BPTB graft and 21 who had ACL reconstruction by use of a QTB graft--were assessed at a minimum follow-up of 24 months after surgery. An accelerated rehabilitation program was adapted, and the rehabilitation protocol was identical for both groups.

RESULTS

The mean side-to-side difference as measured with a KT-2000 arthrometer (MEDmetric, San Diego, CA) was 2.73 mm (SD, 1.45 mm) in the BPTB group and 2.79 mm (SD, 1.32 mm) in the QTB group (P = .880). Postoperatively, the International Knee Documentation Committee score was grade A or B in 23 patients (85.2%) in the BPTB group and 18 (85.7%) in the QTB group (P = .997). The mean anterior knee pain score was 86.9 in the BPTB group as compared with 90.2 in the QTB group (P = .107). In a kneeling posture, 13 BPTB patients reported discomfort (moderate in 10 and severe in 3) whereas only 4 QTB patients had moderate discomfort (P = .029). No significant differences were found with regard to other activities surveyed.

CONCLUSIONS

A QTB graft attached with the EndoPearl device (Linvatec, Largo, FL) appears to be an effective alternative for single-bundle ACL reconstruction. When followed with an accelerated rehabilitation program, reconstruction with a QTB graft provided knee stability comparable to a BPTB graft but with less kneeling pain than a BPTB graft.

Reconstruction of the anterior cruciate ligament in patients over 50 years

The records of patients aged 50 years or over who underwent primary reconstruction of the anterior cruciate ligament between 1990 and 2002 were reviewed. There were 35 knees in 34 patients that met the inclusion criteria. The mean age of the patients was 57 years (50 to 66) and the mean clinical follow-up was for 72 months (25 to 173). A total of 23 knees were reconstructed with patellar tendon allograft, and 12 with patellar tendon autograft. The mean pre-operative knee extension was 1 degrees (-5 degrees to 10 degrees) and flexion was 129 degrees (125 degrees to 150 degrees) and at follow-up these values were 0 degrees (-5 degrees to 5 degrees) and 135 degrees (120 degrees to 150 degrees), respectively. Pre-operatively there were 31 knees (89%) with a Lachman grade 2+ or 3+. Post-operatively, 33 knees (94%) were Lachman grade 0 or 1+. The mean pre- and post-operative International Knee Documentation Committee scores were 39 (23 to 72) and 90 (33 to 100) respectively. The mean pre- and post-operative Lysholm scores were 50 (18 to 68) and 92 (28 to 100) respectively and the mean University of California Los Angeles activity scores were 8.5 before injury (4 to 10), 4.3 (3 to 6) after injury and 8.3 (4 to 10) post-operatively. There were three graft failures (8.6%) requiring revision. We conclude that reconstruction of the anterior cruciate ligament in carefully-selected patients aged 50 years or over can achieve similar results to those in younger patients, with no increased risk of complications.