[Clinical study on reduction of posterior malleolar fractures via modified Rammelt transfibular approach]

To evaluate the safety and effectiveness of reducing posterior malleolar fractures via the modified Rammelt transfibular approach.

A retrospective analysis was conducted on 26 patients with ankle fractures who met the selection criteria and were admitted between September 2023 and May 2024. There were 13 males and 13 females, aged from 14 to 59 years (median, 43.5 years). Causes of injury included traffic accident (1 case), falls (7 cases), and sprains (18 cases). Time from injury to operation ranged from 1 to 13 days (mean, 3.9 days). According to the Lauge-Hansen classification, there were 5 supination-external rotation type Ⅲ fractures and 21 supination-external rotation type Ⅳ fractures. According to the Bartoníček classification for posterior malleolar fractures, there were 12 type Ⅱ fractures, 10 type Ⅲ fractures, and 4 type Ⅳ fractures. During operation, the fracture was exposed via the modified Rammelt transfibular approach; then, the fracture reduction was achieved under direct vision using techniques such as towel clip traction, posterolateral compression, and lifting with a posterior transverse periosteal elevator; finally, the fracture was fixed using anteroposterior cannulated screws or Kirschner wires. The incision healing was observed after operation. At 4 months after operation, X-ray film and CT were reviewed to evaluate the quality of fracture reduction. The medial clear space, tibiofibular clear space, and the anterior/posterior tibiofibular syndesmotic distances were measured. At last follow-up, the ankle function was assessed using the American Orthopaedic Foot & Ankle Society (AOFAS) score and the range of motion.

The marginal necrosis occurred in 2 lateral malleolar incisions, and superficial infection occurred in 1 lateral malleolar incision; the remaining incisions healed by first intention. All 26 patients were followed up 13-21 months (mean, 15.6 months). X-ray films showed that fractures in 25 patients achieved clinical union within 3-8 months (mean, 5.4 months); 1 case had delayed union of the lateral malleolus. At 4 months after operation, no significant difference was found between the injured and healthy sides in the medial clear space, tibiofibular clear space, or the anterior/posterior tibiofibular syndesmotic distances ( P>0.05). No malreduction of the posterior malleolus or the tibiofibular syndesmosis occurred. At last follow-up, the AOFAS score ranged from 80 to 100 (mean, 91.9). The range of motion ranged from 17° to 22° (mean, 21.0°) in active ankle dorsiflexion and from 40° to 49° (mean, 44.6°) in plantar flexion. Internal fixator was removed in 12 patients at 1 year after operation, with no ankle instability occurring. Ankle joint degeneration was observed in 1 patient at last follow-up.

The modified Rammelt transfibular approach is a safe and reliable technique. It enables precise reduction under direct vision, improves the quality of reduction for the distal tibial articular surface and the tibiofibular syndesmosis, and provides satisfactory ankle functional recovery in short-term follow-up.