[The mallet finger in children and adolescents].

The "mallet finger" in childhood and adolescence differs from the "mallet finger" in adults because of an open or gradually closing epiphysial plate. Thus, our results of conservative and operative treatment were evaluated particularly in consideration of an open growth plate. We analysed retrospectively the data of all patients who suffered a lesion at the extensor tendon insertion between 1996 and 2005 and were treated at our hospital. The coding was done according to age, sex, localisation, typing by Doyle, therapy and functional outcome. The typing by Doyle was extended through dividing type IV A into A1 (=Aitken I) and A2 (=Aitken II). Depending on extension deficits, the results were evaluated as very good (0 degrees ), medium (<15 degrees) and bad (>15 degrees). 76 patients, 45 boys and 31 girls aged 1 to 17 years (average age: 11.3) were studied. In consideration of the modified typing by Doyle, following distribution arose: type I (n=16), type II (n=14), type III (n=0), type IV A1 (n=17), type IV A2 (n=6), type IV B (n=21) and type IV C (n=2). A total of 50 patients was treated conservatively. Out of 26 operatively treated patients, 4 could be classified as type I, 12 as type II, 1 as type IV A1, 2 as type IV A2, 5 as type IV B, and 2 as type IV C. In 81.5 % of all patients no functional extension deficit was seen at the end of treatment; in patients treated conservatively, the percentage rate was 94 %. 6 patients, who were treated primarily operatively, showed poor functional outcome. 2 of these developed a suture track infection, in 2 cases chondral and osseous damage in the joint existed additionally, in one patient there was a comminuted fracture and in one patient a technical operative problem. Even in adolescence, conservative treatment of types I, IV A1 and A2, as well as IV B injuries is promising. A prerequisite is a consequent splint treatment and strict regular lateral X-ray control of the fracture fragment. At the beginning of treatment, we favour a plaster finger splint at an intrinsic plus position with hyperextension in the DIP joint.