Eighty-five patients with grade 2 or grade 3 sprains of the acromioclavicular (AC) joint were evaluated clinically and radiographically 32 months after injury. Group I included 34 patients with grade 2 sprains (Tossy II) and group II included 51 patients with grade 3 injuries (Tossy III). In group I, 15 patients were treated surgically (group Ia) and 19 patients were treated conservatively (group Ib), while in group II, 41 patients were treated surgically (group IIa) and 10 patients were treated conservatively (group IIb). At surgery open reduction and transarticular fixation of the AC joint with Kirschner wires was performed. Conservative treatment included the initial use of a sling or a knapsack bandage and early performance of range-of-motion exercises. Shoulder function was assessed according to the score devised by Constant and Murley. In both groups, 97 of 100 possible points (minimum 72, maximum 100) were obtained after conservative and after surgical treatment. Nine of 10 patients (90%) with grade 3 sprains (group IIb) had more pronounced displacement and increased mobility of the lateral end of the clavicle after conservative treatment. After surgery, dislocation and increased horizontal, mobility of the lateral end of the clavicle occurred in 18 (44%) of 41 patients with grade 3 sprains (group IIa P < 0.0001). However, these findings did not correlate with the functional outcome. At follow-up there was a significant increase in degenerative changes seen on radiographs (P < 0.035) in all patients. Again these findings did not correlate with the functional outcome. More degenerative radiological changes were observed in patients who had undergone surgery (P < 0.003). Patients with grade 2 sprains were more frequently restricted in sporting activity after surgery (P < 0.05). Patients with grade 3 sprains who were treated surgically complained of pain more frequently (P < 0.01), and they returned to work later than patients who were treated conservatively after grade 3 sprains. An additional rehabilitation program guided by a physiotherapist seemed to have no impact on the functional outcome. A total of 56 patients were treated by surgery. Among these patients 11 complications occurred, requiring five additional surgical procedures. Among 29 conservatively treated patients, only in 1 patient did subacromially located arthritic changes of the AC joint have to be removed.
