[Limits of palmar locking-plate osteosynthesis of unstable distal radius fractures]

The use of locking plate systems in the treatment of distal radius fractures has increased during the last years. In the presented study our experience and results after palmar plating of dorsal dislocated distal radius fractures are analysed and presented. Besides the functional and radiological results, the potential surgical risks and the observed complications are discussed.

Over a mean 15-month period, 112 consecutive patients (24 men, 88 women) with an average age of 57 years who were treated for an unstable dorsal dislocated distal radius fracture using the palmar locking-plate system could be assessed. The functional results were compared with the uninjured contralateral side. The subjective pain level was assessed using the visual analogue scale (VAS) and the subjective results were assessed using the Disabilities of the Arm, Shoulder, and Hand (DASH) Score. Radiographic assessment included palmar tilt, radial inclination, and ulnar variance. The objective and subjective functional results were evaluated using the modified Mayo-Wrist Score.

Functional results: extension slashed circle 53.1 degrees (84 % as compared with the uninjured side); flexion slashed circle 45.8 degrees (81 % as compared with the uninjured side); pronation slashed circle 78.7 degrees (95 % as compared with the uninjured side); supination 81.9 degrees (95 % as compared with the uninjured side); grip strength slashed circle 56 Kp (73 % as compared with the uninjured side). Radiological results: postoperative reduction/mean postoperative loss of reduction: radial inclination: slashed circle 20.4 degrees /slashed circle 0.2 degrees ; palmar tilt: slashed circle 0.2 degrees /slashed circle 3.1 degrees ; ulnar variance: 0.08 mm/slashed circle 0.42 mm. Pain values: slashed circle 2.7 points; DASH score: slashed circle 14.8 points; complications: breakage of plates 1 %, screw loosening 3 %, intraarticular screw position 2 %, delayed bone union 4 %, rupture M. extensor pollicis longus 2 %/M. flexor pollicis longus 3 %, peritendinitis extensor tendons 5 %, synovialitis flexor tendons 8 %, CTS 3 %, complex regional pain syndrome 6 %.

Favourable indications for palmar locking plate osteosynthesis are A2, A3, C1 and C2 fractures with big distal fracture fragments. In these cases, additional bone grafting is not needed. In very distal fractures, multidirectional plate-systems are advantageous. Multifragmental C3 fractures show a high complication rate. Additional bone grafting for the metaphyseal defect should be considered.