Editorial Commentary: Built to Last or Just a Trend? Hybrid Graft for Anterior Cruciate Ligament Reconstruction

Editorial Commentary: Anterior Cruciate Ligament Hamstring Autografts Should Be Avoided in Patients Younger Than 25 Years Old: Autograft-Allograft Hybrids Remain Controversial

Some studies have reported no difference between autograft and hybrid anterior cruciate ligament reconstructions. However, other studies have shown a significantly greater revision rate. Consequently, surgeons are reluctant to perform hybrid reconstructions in younger patients with diminutive hamstring autografts and have turned to other autograft graft sources (e.g., quadriceps tendon, patellar tendon). Until we can perform high-quality prospective studies that can definitively answer this question, we should consider avoiding autograft hamstring reconstructions in patients younger than 25 years old so that we are not faced with the dilemma of implanting an undersized autograft or a hybrid graft, as both may be at increased risk for failure.

Comparing Hamstring Autograft With Hybrid Graft for Anterior Cruciate Ligament Reconstruction: A Systematic Review

PURPOSE

To systematically review the literature in an effort to compare the demographics and clinical outcomes of patients undergoing anterior cruciate ligament reconstruction (ACLR) with a hamstring tendon autograft (HT) versus an irradiated or nonirradiated hybrid autograft-allograft.

METHODS

A systematic review of the PubMed, Cochrane Library, and Embase databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All English-language literature that reported general demographics and compared the clinical outcomes of patients undergoing primary ACLR with autograft versus hybrid graft (HG) with a minimum 2-year follow-up was reviewed by 2 independent reviewers. Search terms used were "anterior cruciate ligament" and "hybrid graft." Patients were assessed based on graft failure, anteroposterior laxity, and patient-reported outcomes (Knee Injury and Osteoarthritis Outcome Score, visual analog scale, Subjective International Knee Documentation Committee score, Lysholm, and Tegner scores). Study quality was evaluated with the Modified Coleman Methodology Score and ROBINS-I risk of bias tool.

RESULTS

Twelve studies (1 level II, 11 level III) met inclusion criteria (follow-up, 2.0-8.9 years), including 471 patients undergoing ACLR with an irradiated hybrid graft (IH), 89 patients with a nonirradiated hybrid graft, and 829 patients with HT. Graft diameter ranged from 7.5 to 10.0 mm and from 6.5 to 10.0 mm in HG and HT patients, respectively. Overall, graft failure ranged from 0% to 30.0% and from 0% to 28.3% in HG and HT patients, respectively (I² = 35.9%; 95% confidence interval 0%-74.8%). Among HG patients, graft failure ranged from 0%-30.0% and from 2.4%-4.2% in IH and nonirradiated hybrid graft groups, respectively (I² = 33.6%; 95% confidence interval, 0%-71.8%). Results for postoperative anteroposterior laxity and patient-reported outcomes were also inconsistent.

CONCLUSIONS

Patients undergoing ACLR with HT demonstrate inconsistent differences in clinical outcomes at midterm follow-up compared with IH patients.

LEVEL OF EVIDENCE

III, systematic review of level II and III studies.

Editorial Commentary: My Harvested Hamstring Autograft Is Too Small. Now What?

A harvested hamstring autograft that is too small is a technical challenge for an effective anterior cruciate ligament reconstruction. One potential solution is to assemble the graft differently to maximize the diameter and length of the graft. Compared with the traditional, all-inside, 4-strand graft preparation, alternative graft constructs could be further explored and evaluated.