Background
Loss of initial reduction of the acromioclavicular (AC) joint following coracoclavicular (CC) ligament reconstruction remains a challenge for various repair techniques. Previous studies using polydioxanone suture cerclage augments for CC ligament reconstruction demonstrated poor clinical and biomechanical outcomes. Tape style sutures have recently gained popularity due to their added stiffness and strength relative to traditional sutures. These tape cerclage systems have yet to be biomechanically studied in CC ligament reconstruction.
Purpose
To determine the efficacy of a tape cerclage system as an augment to CC ligament reconstruction.
Study Design: Controlled laboratory study
Methods
Twenty-four human cadaveric shoulders were utilized. These were divided into four repair groups: anatomic coracoclavicular ligament reconstruction (ACCR), ACCR with a tape cerclage augment (ACCR + C), tendon graft sling with a cerclage augment (TGS + C), or tape cerclage alone (CS). The repairs underwent superior/inferior cyclic loading to evaluate for displacement. Specimens were visually inspected for cortical erosion by the tape cerclage following cyclic loading. Finally, the constructs underwent superior plane load to failure testing.
Results
Less displacement after cyclic loading was observed in the ACCR + C (.42mm ± .32), TGS + C (.92mm ± .42), and CS groups (.93mm ± .39) compared to the ACCR group (4.42mm ± 3.40; p=.002). ACCR + C (813.3N ± 257.5), TGS + C (558.0N ± 120.7), and CS (759.5N ± 173.7) demonstrated significantly greater load at failure relative to the ACCR group (329.2N ± 118.2; p<.001). The ACCR + C (60.88N/mm ± 17.3), TGS + C (44.97N/mm ± 9.15), and CS (54.52N/mm ± 14.24) conferred greater stiffness than the ACCR group (27.43N/mm ± 6.94; p = .001). No cortical erosion was demonstrated in any specimen after cyclic loading.
Conclusion
Repairs utilizing a tape cerclage system confer significantly greater load to failure and stiffness, as well as decreased displacement with cyclic loading, when compared to traditional ACCR repair.