Change of wrist motion before and after fixation of the distal radioulnar joint and resection of the distal ulna in a cadaveric model.

OBJECTIVE: Recent study suggests the distal radioulnar joint (DRUJ) plays a role in flexion and extension of the wrist. We examined the range of motion (ROM) of the wrist before and after DRUJ fixation and distal ulnar resection in a cadaveric model. METHODS: Twenty fresh cadaveric human wrists were transected and treated with two sequential interventions: (a) DRUJ fixation, and (b) distal ulnar resection. The angle of maximum flexion and extension of the wrist was measured before and after the procedures. Maximum force to the wrist was determined before the procedures using a digital pressure monitor. RESULTS: The mean maximum wrist flexion ROM was 84.2° before the procedures. The ROM decreased to 82.5° after DRUJ fixation, and significantly increased to 88.2° after subsequent resection of the distal ulna. The mean maximum wrist extension ROM before the procedures was 73.5°. The ROM decreased to 71.6° after DRUJ fixation, and significantly increased to 77.1° after subsequent resection of the distal ulna. CONCLUSIONS: Motion of the wrist is affected by DRUJ. This study suggests that the DRUJ might contribute to the ROM in flexion and extension of the wrist.

A Novel Alaska Pollock Gelatin Sealant Shows Higher Bonding Strength and Nerve Regeneration Comparable to That of Fibrin Sealant in a Cadaveric Model and a Rat Model.

BACKGROUND: A novel biocompatible sealant composed of Alaska pollock-derived gelatin (ApGltn) has recently shown good burst strength and biocompatibility in a porcine aorta. The purpose of this study was to investigate the bonding strength and biocompatibility of the ApGltn sealant in transected digital nerves of fresh frozen cadavers and in the sciatic nerves of a rat model. METHODS: Eighty human digital nerves of fresh frozen cadavers were transected for biomechanical traction testing. They were treated with four surgical interventions: (1) suture plus ApGltn sealant; (2) suture; (3) ApGltn sealant; and (4) fibrin sealant. Forty-three sciatic nerves of male Wistar rats were used for functional and histopathologic evaluation. They were treated with six surgical interventions: (1) suture plus ApGltn sealant; (2) suture; (3) ApGltn sealant; (4) fibrin sealant; (5) resection with a 5-mm gap (10 rats per group); and (6) sham operation (three rats). Macroscopic confirmation, muscle weight measurement, and histopathologic findings including G-ratio were examined 8 weeks after the procedure. RESULTS: The maximum failure load of the ApGltn sealant was significantly higher than that of a fibrin sealant (0.22 ± 0.05 N versus 0.06 ± 0.04 N). The maximum failure load of the ApGltn sealant was significantly lower that of suture plus ApGltn sealant (1.37 N) and suture (1.27 N). Functional evaluation and histologic examination showed that sciatic nerves repaired with ApGltn sealant showed similar nerve recovery compared to repair with the suture and fibrin sealant. CONCLUSION: The ApGltn sealant showed higher bonding strength and equal effect of nerve regeneration when compared with the fibrin sealant.