Intraoperative Conversion to Five-Strand Hamstring Autograft Configuration Significantly Increases Anterior Cruciate Ligament Graft Diameter Independent of Patient Characteristics

The effectiveness of quadrupled semitendinosus graft technique in anterior cruciate ligament reconstruction: A network meta-analysis assessing various graft preparation techniques

PURPOSE

This study aims to perform a network meta-analysis of hamstring graft preparation techniques to enhance anterior cruciate ligament (ACL) reconstruction guidelines and inform clinical decision-making in patients with primary ACL rupture.

METHODS

A review of the literature, from 1 January 1990, to 31 August 2023, was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, focusing on the clinical outcomes of various hamstring graft preparation techniques. Forty-six studies (over 4800 knees) were analysed. Eight graft compositions: doubled hamstring (ST/G)-1978 grafts, doubled hamstring with augmentation (ST/G+A)-586 grafts, tripled semitendinosus (3ST)-124 grafts, quadrupled semitendinosus (4ST)-1273 grafts, five-strand tripled semitendinosus + doubled gracilis (3ST/2GR-839 grafts, six-strand tripled semitendinosus + tripled gracilis (3ST/3GR)-335 grafts, seven-strand quadrupled semitendinosus + tripled gracilis (4ST/3GR)-11 grafts and ≥eight strands-24 grafts were compared, considering graft sizes, laxity, muscle strength, range-of-motion, patient-reported outcome measures (PROMs), return to sport (RTS) and adverse events.

RESULTS

The 4ST grafts fared better than the ST/G grafts in the International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Outcome Score (KOOS) Sport, KOOS Q and RTS (mean difference [MD], -1.69; p = 0.0159; MD, -1.55; p = 0.0325; MD, -1.93; p = 0.001; odds ratio: 3.13; p < 0.0001). The IKDC differed significantly between the 4ST and ST/G+A groups (MD, 1.88; p = 0.046). The ST/G+A resulted in the lowest knee laxity, surpassing the ST/G, 3ST and 4ST. The ST/G had the smallest diameter (ST/G vs. ST/G+A: MD, 1.26; 95% confidence interval [CI]: 0.67-1.86, p < 0.0001). Reduced failure rates were noted with the 3ST/2GR (3ST/2GR vs. ST/G: MD, 6.93; p = 0.009) and 3ST/3GR (3ST/3GR vs. ST/G: MD, 53.64; p = 0.006).

CONCLUSION

The ideal hamstring graft for ACLR should be individualized. A 4ST graft is likely to yield good PROMs. For high stability and rapid RTS, adding augmentation to the graft is advisable. The ST/G is the thinnest graft possible.

LEVEL OF EVIDENCE

Network meta-analysis of level I-III studies.

Hamstring autografts demonstrate either similar or inferior outcomes to quadriceps or bone-patellar tendon-bone autografts in revision anterior cruciate ligament reconstruction: A systematic review of comparative studies

PURPOSE

To evaluate the clinical outcomes in patients undergoing revision anterior cruciate ligament reconstruction (r-ACLR) using hamstring tendon (HT) autografts with those using either quadriceps tendon (QT) or bone-patellar tendon-bone (BPTB) autografts or allografts.

METHODS

Three databases were searched on 8 August 2023. The authors adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Revised Assessment of Multiple Systematic Reviews (R-AMSTAR) guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. Data on demographics, surgical details, patient-reported outcome measures (PROMs), rates of instability, failure and return to sport (RTS) were extracted.

RESULTS

Eleven studies comprising 859 patients were included in this review. Five studies compared HT and QT autografts. One study each reported greater IKDC scores (p = 0.04) and Tegner scores (p = 0.04) in the QT group, while one study each reported higher anterior translation (p = 0.04), rates of positive pivot shift (p = 0.03) and rates of failure (p = 0.03) in the HT group. Six studies compared HT and BPTB autografts with one study each reporting greater Lysholm scores (p = 0.02) and less side-to-side anterior laxity (p < 0.01) in the BPTB group. Two studies compared HT autografts with allografts with only one study reporting a faster time to RTS in the HT group than the allograft group (p < 0.001). All other comparisons were not significant.

CONCLUSIONS

HT autografts result in either similar or inferior outcomes in r-ACLR when compared to QT or BPTB autograft options. Allografts resulted in similar outcomes to HT autografts apart from greater time to RTS for r-ACLR.

LEVEL OF EVIDENCE

Level III.

Anterior cruciate ligament reconstruction with six and eight-strand hamstring tendon autografts produces adequate graft dimensions and functional outcomes: A systematic review

PURPOSE

This study aims to summarize the graft dimensions, failure rates, return-to-sport rates and patient-reported outcome measures (PROMs) following anterior cruciate ligament reconstruction (ACLR) with six or eight-strand hamstring tendon autografts (6SHG or 8SHG).

METHODS

Three databases were searched from inception to 12 February 2024. The authors adhered to PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. All clinical studies reporting patient demographics, objective clinical outcomes and PROMs following ACLR with 6SHG or 8SHG were included for data synthesis. PROMs included the International Knee Documentation Committee (IKDC), Lysholm and Tegner scores.

RESULTS

Thirteen studies comprising 1103 patients were included (mean age: 30.6 years). The transtibial technique was used in all studies, except one study using anatomic ACLR (n = 38), and one study using transtibial and all-inside ACLR (n = 41). Eight studies comprising 512 patients used 6SHG, four studies comprising 507 patients 8SHG and two studies comprising 97 patients used either. Mean graft diameters ranged from 8.0 to 9.2 mm (6SHG) and 9.1 to 9.9 mm (8SHG). Mean graft lengths for 49 6SHG patients ranged from 60.0 to 83.3 mm. The failure rate for 817 patients (6SHG or 8SHG) was 4.8% (0.0%-20.0%). The return-to-sport rate for 112 patients (6SHG or 8SHG) was 75.9% (69.7%-100.0%). Mean IKDC, Lysholm and Tegner scores for 6SHG or 8SHG were 88.4 (86.1-96.3), 91.7 (90.4-96.5) and 6.9 (6.5-7.3), respectively.

CONCLUSIONS

Both 6SHG and 8SHG produced graft diameters <8 mm. Data regarding PROMs suggested good patient satisfaction based on established criteria. Re-rupture and return-to-sport rates were 4.8% and 75.9%, respectively.

LEVEL OF EVIDENCE

Level IV.

Single bundle hamstrings autograft preparation techniques for anterior cruciate ligament reconstruction: current concepts

Anterior cruciate ligament reconstruction (ACLR) is one of the most common orthopedic procedures, and huge variation exists in the surgical technique. Single bundle hamstrings autograft reconstruction is a common method and has good clinical outcomes. A criticism of the hamstrings autograft is a small graft diameter, often less than 8-mm, which has been associated with increased re-rupture rates. Several graft preparation techniques for single bundle hamstrings autograft exist. Perioperative decisions include the number of tendons utilized, number of graft strands, graft configuration, and femoral and tibial fixation methods. Awareness of the minimum tendon and graft length required to produce each graft variation is necessary to avoid common pitfalls. However, intraoperative graft modification is possible to maximize graft diameter, and obtain proper fixation. The objective of this current concepts review is to describe the indications, surgical anatomy, technique, intraoperative tips, clinical outcomes, and complications for single bundle hamstrings autograft preparation techniques in ACLR.

Estimated diameter increase from a 4S to a 6S hamstring graft configuration - A cadaveric study

PURPOSE

Graft diameter in anterior cruciate ligament reconstructions has been shown to influence the risk of failure. It is therefore important to be able to adjust the graft configuration to modify the diameter. To measure the impact of a 6-strand (6S) hamstring autograft configuration on graft diameter compared to the standard 4-strand (4S) configuration.

METHODS

Cadaveric study on 33 knees, using the usual hamstring graft harvesting technique. Semitendinosus and gracilis tendons were harvested and their length, width, and diameter were measured in 4S and 6S configurations separately by three evaluators.

RESULTS

6S configuration leads to a median increase of 1.5 (range: 0.0-2.0) mm in diameter compared to 4S (p < 0.001). A graft diameter of more than 8 mm is attained in less than a third of 4S grafts within this population in comparison to 84% when the 6S configuration is used.

DISCUSSION

The 6S hamstring graft configuration increases the graft diameter by a median of 1.5 millimeters compared to the traditional 4S configuration. It can reliably be used to obtain an 8.5 mm graft diameter or more in cases where the semitendinosus measures at least 270.5 mm and the 4S configuration has a diameter of 7.5 mm or 8 mm. This information helps to better delineate the impact of a 6S configuration in a pre-operative or intra-operative setting to optimize the decisional process and surgical flow and to easily adapt the graft diameter.

LEVEL OF EVIDENCE

V (cadaveric study).

Effects of General Anesthesia Plus Multimodal Analgesia on Immediate Perioperative Outcomes of Hamstring Tendon Autograft ACL Reconstruction

Anterior cruciate ligament reconstruction with hamstring tendon autograft (H-ACLR) is a standard ambulatory procedure with the potential for considerable postoperative pain. We hypothesized that general anesthesia combined with a multimodal analgesia regimen would reduce postoperative opioid use associated with H-ACLR.

Methods

This study was a single-center, surgeon-stratified, double-blinded, placebo-controlled, randomized clinical trial. The primary end point was the total postoperative opioid use during the immediate postoperative period, and secondary outcomes included postoperative knee pain, adverse events, and ambulatory discharge efficiency.

Results

One hundred and twelve subjects, 18 to 52 years of age, were randomized to placebo (57 subjects) or combination multimodal analgesia (MA) (55 subjects). The MA group required fewer opioids postoperatively (mean ± standard deviation, 9.81 ± 7.58 versus 13.88 ± 8.49 morphine milligram equivalents; p = 0.010; effect size = -0.51). Similarly, the MA group required fewer opioids within the first 24 hours postoperatively (mean ± standard deviation, 16.56 ± 10.77 versus 22.13 ± 10.66 morphine milligram equivalents; p = 0.008; effect size = -0.52). The subjects in the MA group reported lower posteromedial knee pain (median [interquartile range, IQR]: 3.0 [0.0 to 5.0] versus 4.0 [2.0 to 5.0]; p = 0.027) at 1 hour postoperatively. Nausea medication was required for 10.5% of the subjects receiving the placebo versus 14.5% of the subjects receiving MA (p = 0.577). Pruritis was reported for 17.5% of subjects receiving the placebo versus 14.5% receiving MA (p = 0.798). The median time to discharge was 177 minutes (IQR, 150.5 to 201.0 minutes) for subjects receiving placebo versus 188 minutes (IQR, 160.0 to 222.0 minutes) for those receiving MA (p = 0.271).

Conclusions

A combination of general anesthesia and local, regional, oral, and intravenous multimodal analgesia appears to reduce postoperative opioid requirements after H-ACLR compared with placebo. Adding preoperative patient education and focusing on donor-site analgesia may maximize perioperative outcomes.

Level of Evidence

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Hamstring graft diameter above 7 mm has a lower risk of failure following anterior cruciate ligament reconstruction

PURPOSE

Multi-stranded hamstring-tendon autografts have been widely used for anterior cruciate ligament reconstruction (ACLR) surgeries. Recently, smaller diameter hamstring autografts have been linked with the risk of failure or graft rupture. However, there is limited evidence concerning the optimal diameter of the hamstring autografts for ACLR. The current systematic review and meta-analysis analysed the association of ACLR failure with the diameter of hamstring autografts.

METHODS

A systematic search of three major scientific databases (Pubmed, EMBASE, and Cochrane library) was conducted to identify studies that presented ACLR failure-related outcomes with different diameters of hamstring autografts. The pooled data from the included studies were analysed to investigate the association between ACLR failure and the cut-off diameters of 6, 7, 8, and 9 mm. Subgroup analyses based on the level of evidence and follow-up duration were also performed at each cut-off diameter.

RESULTS

Of the 2282 studies screened, 16 reported failure rates with hamstring autografts of different diameters, 15 of which were included in the meta-analysis. A graft diameter ≥ 7 mm was associated with significantly lower ACLR failure rates than a graft diameter < 7 mm (p = 0.005), based on pooled data of 19,799 cases. Age < 20 years and higher physical activity were associated with significantly higher ACLR failure rates.

CONCLUSION

The current systematic review suggests that the hamstring graft diameter for ACLR should be more than 7 mm considering the significantly higher failure rates with graft diameters less than 7 mm.

LEVEL OF EVIDENCE

Level IV.

Quadriceps Tendon Autograft in Pediatric ACL Reconstruction: Graft Dimensions and Prediction of Size on Preoperative MRI

Background

There is increased interest in quadriceps autograft anterior cruciate ligament (ACL) reconstruction in the pediatric population.

Purpose

To evaluate children and adolescents who underwent ACL reconstruction using a quadriceps autograft to determine the properties of the harvested graft and to assess the value of demographic, anthropometric, and magnetic resonance imaging (MRI) measurements in predicting the graft size preoperatively.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

A retrospective database search was performed from January 2018 through October 2020 for patients undergoing ACL reconstruction. Patients <18 years old at the time of surgery in whom a quadriceps tendon autograft was used were selected. Demographic data and anthropometric measurements were recorded, and graft measurements were abstracted from the operative notes. Knee MRI scans were reviewed to measure the quadriceps tendon thickness on sagittal cuts. Graft length and diameter were then correlated with anthropometric and radiographic data.

Results

A total of 169 patients (98 male) were included in the final analysis, with a median age of 15 years (range, 9-17 years). A tendon length ≥65 mm was harvested in 159 (94%) patients. The final graft diameter was 8.4 ± 0.7 mm (mean ± SD; range, 7-11 mm). All patients had a graft diameter ≥7 mm, and 139 (82%) had a diameter ≥8 mm. Preconditioning decreased the graft diameter by a mean 0.67 ± 0.23 mm. Age (P = .04) and quadriceps thickness on MRI (P = .003) were significant predictors of the final graft diameter. An MRI sagittal thickness >6.7 mm was 97.4% sensitive for obtaining a graft ≥8 mm in diameter.

Conclusion

Our findings suggest that tendon-only quadriceps autograft is a reliable graft source in pediatric ACL reconstruction, yielding a graft diameter ≥8 mm in 82% of pediatric patients. Furthermore, preoperative MRI measurements can be reliably used to predict a graft of adequate diameter in children and adolescents undergoing ACL reconstruction, with a sagittal thickness >6.7 mm being highly predictive of a final graft size ≥8 mm.

Five- and six-strand hamstring grafts consistently produce appropriate graft diameters for anterior cruciate ligament reconstruction

PURPOSE

Hamstring tendon graft diameter less than 8 mm has been correlated with an increased risk of anterior cruciate ligament reconstruction (ACLR) graft failure. The purpose of this study was to measure and compare the diameter of 3-, 4-, 5-, and 6-strand gracilis and semitendinosus (ST) hamstring tendon (HT) ACLR grafts, and to determine if there is a correlation between anthropometric data, HT length, and diameter of the HT ACLR graft.

METHODS

Male patients (n = 78) undergoing primary or revision ACLR with a HT autograft between July 2018 and March 2020 were recruited. Pre-operative anthropometric data was collected. Gracilis and ST tendons were harvested and the length and diameter measured. The following HT graft configurations were prepared in each patient: triple ST; double gracilis + double ST; double gracilis + triple ST; triple gracilis + triple ST. Paired t-tests and Pearson's correlation coefficients were used to assess demographics, anthropometrics, graft diameter, and tendon length. A non-parametric test was used to compare femoral and tibial ACL graft diameters of the 3-, 4-, 5-, and 6-strand HT graft configurations.

RESULTS

For the femoral end, 10%, 19%, 69% and 86% of the patients achieved graft diameters of equal to or greater than 8 mm in 3-, 4-, 5- and 6-strand HT graft configurations respectively. For the tibial end, 27%, 10%, 83%, and 92% of the patients achieved graft diameters of equal to or greater than 8 mm in 3-, 4-, 5-, and 6-strand HT graft configurations respectively. The largest increases in HT graft diameters were noted between the femoral end of 6- vs. 3-strand grafts (mean difference 1.7 ± 0.5 mm; p < 0.001) and between the tibial end of 6- vs. 4-strand grafts (mean difference 2.0 ± 0.5 mm; p < 0.001). Height and leg length were moderately positively correlated with ST tendon length (r = 0.54-0.51) and gracilis tendon length (r = 0.52-0.45), and thigh and shank lengths were moderately positively correlated with ST tendon length (r = 0.43 and 0.40, respectively).

CONCLUSION

Traditional 4-strand HT ACL autografts in male patients undergoing ACLR in the United Arab Emirates result in graft diameters less than 8 mm in the majority of patients.

LEVEL OF EVIDENCE

III.