Complications following internal fixation of unstable distal radius fracture with a palmar locking-plate

Objectives: The increasing number of fixed-angle plate systems used to treat distal radius fractures carries with it the problem of determining the optimal fixation for unstable fractures. Our goal was to analyze the clinical and radiological outcomes of patients with displaced, unstable distal radius fractures treated with a palmar fixed-angle plate. Design: Prospective protocol; multicenter clinical study; retrospective analysis. Setting: Level I university trauma centers. Patients: Over a mean 15-month period (range, 12 to 27 months), 141 consecutive patients were treated for an unstable dorsally displaced distal radius fracture of which 114 or 81% were followed for 1 year or longer. Intervention: Open reduction and palmar internal fixation with a fixed-angle plate (2.4 mm LCP Distal Radius Plates; Synthes, Salzburg, Austria). Indication for surgical treatment was the inability to obtain or maintain fracture or articular alignment after initial closed reduction. Main Outcome Measures: In a follow-up period, which had to be longer than 12 months, objective and subjective functional results (active range of motion; strength; Disabilities of the Ann, Shoulder, and Hand (DASH) score; visual analog scale (VAS); Green and O'Brien Score) and radiographic assessment (palmar tilt, radial inclination, ulnar variance, fracture union) were assessed. Potentials for complications were given special attention. Results: In the 114 patients followed for a minimum of 12 months, there were 21 men and 93 women with a mean age of 5 7 years (17 to 79 years). Fractures were classified according to the AO/ASIF classification system as type A2 (n = 39), A3 (n = 16), C1 (n = 24), C2 (n = 30), or C3 (n = 5). The modified Green and O'Brien Score revealed 31 excellent, 54 good, 23 fair, and 6 poor results. Active wrist motion averaged 54 degrees extension (82% as compared with the uninjured side) and 46 degrees flexion (72% as compared with the uninjured side). The average pronation was 81 degrees (95% as compared with the uninjured side), and the average supination was 82 degrees (95% as compared with the uninjured side). Mean grip strength at final follow-up was 70% of the uninjured side. Low residual pain values in the wrist were demonstrated: 81 patients (71%) were pain free, 17 patients (15%) had mild pain, 10 patients (9%) had moderate pain, and 6 patients (5%) had severe pain. The DASH score averaged 13 points (range, 0 to 39 points). Fracture union was achieved in all patients. A mean loss of palmar tilt of 3.4 degrees (range, 0 to 8 degrees), radial inclination of 0.4 degrees (range 0 to 2 degrees), and of the ulnar variance of 1.2 nim (range, 0 to 6 mm) was measured. The overall complication rate was 27% (31/114). The most frequent problems were flexor and extensor tendon irritation (57% of the total number of complications), including 2 ruptures of the flexor pollicis longus tendon, 2 ruptures of the extensor pollicis longus tendon, 4 cases of extensor tendon tenosynovitis, and 9 cases of flexor tendon tenosynovitis. Carpal tunnel syndrome was observed in 3 patients, and complex regional pain syndrome occurred in 5 patients. In 2 cases, loosening of a single screw was seen. Delayed fracture union occurred in 3 patients, and intraoperative intraarticular screw displacement was recognized in I patient. Neither clinical outcome nor complication rate were dependent on fracture type (intraarticular versus extraarticular). Conclusion: Fixation of unstable dorsally displaced distal radius fractures with a fixed angle plate provides sufficient stability with minimal loss of reduction. Nevertheless, very distal palmar plate position can interfere with the flexor tendon system, too long screws can penetrate the extensor compartments, and distal screws in comminuted fracture patterns can cut through the subchondral bone and penetrate into the radiocarpal joint. Mindful of these problems, we consider that the complex fracture pattern of an unstable distal radius fracture cannot be treated by a single plate system and approach.