Background: Despite the increasing use of biceps tenodesis, there is a lack of consensus regarding optimal implant choice (suture anchor vs interference screw) and implant placement (suprapectoral vs subpectoral).
Purpose/hypothesis: The purpose was to determine the associations of procedural parameters with the biomechanical performance of biceps tenodesis constructs. The authors hypothesized that ultimate failure load (UFL) would not differ between sub- and suprapectoral repairs or between interference screw and suture anchor constructs and that the number of implants and number of sutures would be positively associated with construct strength.
Study design: Meta-analysis.
Methods: The authors conducted a systematic literature search for studies that measured the biomechanical performance of biceps tenodesis repairs in human cadaveric specimens. Two independent reviewers extracted data from studies that met the inclusion criteria. Meta-regression was then performed on the pooled data set. Outcome variables were UFL and mode of failure. Procedural parameters (fixation type, fixation site, implant diameter, and numbers of implants and sutures used) were included as covariates. Twenty-five biomechanical studies, representing 494 cadaveric specimens, met the inclusion criteria.
Results: The use of interference screws (vs suture anchors) was associated with a mean 86 N-greater UFL (95% CI, 34-138 N; P = .002). Each additional suture used to attach the tendon to the implant was associated with a mean 53 N-greater UFL (95% CI, 24-81 N; P = .001). Multivariate analysis found no significant association between fixation site and UFL. Finally, the use of suture anchors and fewer number of sutures were both independently associated with lower odds of native tissue failure as opposed to implant pullout.
Conclusion: These findings suggest that fixation with interference screws, rather than suture anchors, and the use of more sutures are associated with greater biceps tenodesis strength, as well as higher odds of native tissue failure versus implant pullout. Although constructs with suture anchors show inferior UFL compared with those with interference screws, incorporation of additional sutures may increase the strength of suture anchor constructs. Supra- and subpectoral repairs provide equivalent biomechanical strength when controlling for potential confounders.
Keywords: biceps tenodesis; biomechanical strength; interference screw; mode of failure; subpectoral repair; suprapectoral repair; suture anchor; ultimate failure load.