Comparison of Interface Pressure, Contact Surface Area, and Percent Area of Coverage Between Two Suture Configurations for Hill-Sachs Remplissage

Purpose: To compare maximum contact pressure, contact surface area, and the percent area of coverage of the bone-tendon interface in the remplissage procedure between two different suture configurations (independent mattress versus double-pulley). Methods: A sample size of seven specimens per group was defined by a 96% power analysis. Hill-Sachs lesions were created in all fourteen ex vivo ovine shoulders, corresponding to a 30% defect of the axial diameter of the humeral head (significant lesion according to literature). The defects were repaired using the remplissage technique applying one of the two randomly chosen suture configurations: two independent mattress sutures or a double-pulley. The contact pressure and contact surface area, as well as percent defect coverage, were recorded using a film sensitive to these parameters. Independent nonparametric tests (Mann-Whitney) were used for the statistical analysis. Results: The double-pulley group exhibited an average pressure of 0.128 ± 0.018 mPa, the contact surface of 0.199 ± 0.044 cm2, and 41.97 ± 9.8% defect coverage. The independent mattress group showed an average pressure of 0.102 ± 0.01 mPa, the contact surface of 0.081 ± 0.041 cm2, and defect coverage of 15.6 ± 8.1%. All three parameters were statistically superior in the double-pulley group (p=0.038, p=0.008, and p=0.008, respectively) Conclusion: The remplissage technique using the double-pulley configuration, presented superior biomechanical characteristics, in terms of contact pressure, contact area, and percent coverage of the defect, compared to the simple independent mattress configuration.