Introduction: Although more than 30 different surgical procedures to achieve solid ankle fusion were described, after septic joint destruction or ongoing infection external fixation is preferred. In 1999 the referring institution reported on 45 cases with internal (screw) fixation and additional external fixation [1]. Later on we used hybrid external fixation including transfixation of the midfoot [2]. Since range of motion of the middle and forefoot is of great importance for limb function we designed a prospective study to compare fusion rate and limb function after ankle fusion without foot or midfoot transfixation.

Patients and Methods: Between 9/2000 and 2/2002 18 patients with septic ankle destruction were admitted for ankle fusion. 10 patients were treated with a fine wire ring fixator using 2 full rings in the tibia and one 5/8 shaped ring in the calcaneus and talus. Compression was applicated only between the distal tibia and the talus. Every 14 days the wires were retensioned. 8 patients were treated with a titanium compression nail in an antegrad technique. All operations were done by one surgeon. 14 patients had a posttraumatic osteitis complicated in 6 cases by polyneurophathy and in two cases previous fusion failed. 4 patients suffered from diabetic polyneuropathy, 2 of them with ongoing infection. In both techniques weight bearing was allowed after 3 weeks.

Results: External fixator was removed 16 weeks after operation on average (14w–18w). Solid fusion was achieved in 16 cases (88%). In 3 patients the fistula persisted in one of them fusion failed. Dynamic pedobarography showed better results in patients without fixation of the subtalar joint. (Compression nail)

Conclusion: The study showed similar fusion rates compared with surgical procedures including transfixation of the whole foot. Range of motion of the not fused joints of the foot was better because early physioptherapy was performed. The fixation of the fore and mid foot is not necessary to achieve solid fusion by increased stability.