gms | German Medical Science

Objectives/Interrogation: Distal radius fractures are now commonly treated with a volar locking plate. However, flexor tendon problems such as tendon irritation and rupture caused by prominence of the implant have been reported. Intramedullary implants can stabilize distal radius fracture and minimally affect flexor tendons and muscles around the site, but the literatures about radiographic and functional results of placing such implants are limited.

Object of this study was to investigate the radiographic and functional results and complications of distal radius fracture treated with intramedullary implants in patients older than 50 years old.

Methods: From among the patients with extra-articular or simple intra-articular fractures with a sagittal fracture line who we treated, we retrospectively evaluated those over 50 years old treated by intramedullary implant (Micronail, Wright Medical Technology) who had at least 6 months follow up. We investigated fracture type using the AO classification, radiographic parameters, range of motion, grip strength, complications, and the Mayo modified wrist score.

Results and Conclusions: We evaluated 90 patients (11 men, 79 women; mean age 69.5 years,50-88 years). According to the AO classification, there were 54 type A patients, 36 type C patients. Preoperative mean radial inclination was 18 degrees, volar tilt was -17.5 degrees, and ulnar variance was 2.0 mm. Immediate postoperative average radial inclination was 25.8 degrees, volar tilt 9.3 degrees, and ulnar variance -0.2 mm. At final follow up, all fractures had bony union, and the average radial inclination was 25.1 degrees, volar tilt 11.7 degrees, and ulnar variance 0.2 mm. Average range of motion was 70.6 degrees of dorsal wrist flexion, 61 degrees of palmar wrist flexion, 79.1 degrees of forearm pronation, and 89.6 degrees of forearm supination. Average percentile grip strength of the uninjured side was 95.8%. No patients had flexor tendon irritation or rupture. Two patient had neuritis of a superficial branch of the radial nerve, which resolved within 3 months. The average Mayo modified wrist score at final follow up was 93.4 points, with 56 patients graded as excellent, 29 good, 5 fair.

Intramedullary implants to treat dorsally displaced extra-articular or simple intra-articular distal radius fracture afforded good radiological and functional outcomes. This procedure was free from flexor tendon problems, and specific complications about radial nerve sensory branch were temporary.