A Contact Pressure Analysis Comparing an All-Inside and Inside-Out Surgical Repair Technique for Bucket-Handle Medial Meniscus Tears

摘要

Purpose: To directly compare effectiveness of the inside-out and all-inside medial meniscal repair techniques in restoring native contact area and contact pressure across the medial tibial plateau at multiple knee flexion angles. Methods: Twelve male, nonpaired (n = 12), fresh-frozen human cadaveric knees underwent a series of 5 consecutive states: (1) intact medial meniscus, (2) MCLtear and repair, (3) simulated bucket-handle longitudinal tear of the medial meniscus, (4) inside-outmeniscal repair, and (5) all-inside meniscal repair. Knees were loaded with a 1,000-N axial compressive force at 5 knee flexion angles (0 degrees, 30 degrees, 45 degrees, 60 degrees, 90 degrees), and contact area, mean contact pressure, and peak contact pressure were calculated using thin film pressure sensors. Results: No significant differences were observed between the inside-out and all-inside repair techniques at any flexion angle for contact area, mean contact pressure, and peak contact pressure (all P >.791). Compared with the torn meniscus state, inside-out and all-inside repair techniques resulted in increased contact area at all flexion angles (all P <.005 and all P <.037, respectively), decreased mean contact pressure at all flexion angles (all P <.007 and all P <.001, respectively) except for 0 degrees(P =.097 and P =.39, respectively), and decreased peak contact pressure at all flexion angles (all P <.001, all P <.001, respectively) except for 0 degrees(P =.080 and P=.544, respectively). However, there were significant differences in contact area and peak contact pressure between the intact state and inside-out technique at angles >= 45 degrees (all P<. 014 and all P<. 032, respectively). Additionally, therewere significant differences between the intact state and all-inside technique in contact area at 60 degrees and 90 degrees and peak contact pressure at 90 degrees(both P<.005 and P =.004, respectively). Median values of intact contact area, mean contact pressure, and peak contact pressure over the tested flexion angles ranged from 498 to 561 mm(2), 786 to 997 N/mm(2), and 1,990 to 2,215 N/mm(2), respectively. Conclusions: Contact area, mean contact pressure, and peak contact pressure were not significantly different between the all-inside and inside-out repair techniques at any tested flexion angle. Both techniques adequately restored native meniscus biomechanics near an intact level. Clinical Relevance: An all-inside repair technique provided similar, native state-restoring contact mechanics compared with an inside-out repair technique for the treatment of displaced bucket handle tears of the medial meniscus. Thus, both techniques may adequately decrease the likelihood of cartilage degeneration.