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The aim of the present cadaveric study was to assess resistance to first metacarpal subsidence of three techniques of suspensionplasty after trapeziectomy. In total, 18 forearms (mean age 60 years [range 20-89]) were used with six specimens per surgical technique: palmar oblique ligament reconstruction with tendon interposition (LRTI), abductor pollicis longus (APL) suspensionplasty, or suture suspensionplasty. There was no significant difference in mean trapezial space height after trapeziectomy and suspensionplasty compared to the preoperative trapezial height. However, after simulation of physiological lateral pinch, there was a significant ( p <  0.05) difference in mean trapezial space height between the APL suspensionplasty and the suture suspensionplasty compared to the LRTI group. After axial loading, there was significantly greater metacarpal subsidence in the LRTI group compared to the APL and suture suspensionplasty groups but no statistically significant difference between the suture suspensionplasty and the APL suspensionplasty groups. Level of evidence: V., Competing Interests: Declaration of conflicting interestsThe authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

We compared four methods of metacarpal shaft fixation: 2.2 mm intramedullary headless compression screw; 3.0 mm intramedullary headless compression screw; intramedullary K-wire fixation; and dorsal plate fixation. Transverse mid-diaphyseal fractures were created in 64 metacarpal sawbones and were assigned into four groups. Peak load to failure and stiffness were measured in cantilever bending and torsion. We found that dorsal plating had the highest peak load to failure. However, initial bending stiffness of the 3.0 mm intramedullary headless compression screw was higher than that of the dorsal plates. In torsion testing, dorsal plating had the highest peak torque, but there was no significant difference in torsional stiffness between the plate and intramedullary headless compression screw constructs. We concluded that intramedullary headless compression screw fixation is biomechanically superior to K-wires in cantilever bending and torsion; however, it is less stable than dorsal plating. In our study, the initial stability provided by K-wire fixation was sufficient to cope with expected loads in the early rehabilitation period, whereas dorsal plates and IHCS constructs provided stability far in excess of what is required.