[Treatment of syndesmosis diastasis with screw fixation in ankle fractures].

OBJECTIVE

To explore the operative method for the treatment of syndesmosis injury in ankle fractures.

METHODS

A retrospective study was done on 21 ankles of 20 patients included male 11 and female 9;the range of age were from 27 to 52 years with an average of 36 years) with syndesmosis injury in closed ankle fractures from September 2005 to December 2007. All patients with ankle fractures and syndesmosis injury were diagnosed by the history, physical examination and radiology, then treated with open reduction, internal fixation, and syndesmotic stabilization with a three-cortices syndesmotic screw according to the Lauge-Hansen classification system. Radiological evaluation comprised tibiofibular overlap, total clear space and medial clear space. The clinical effects were evaluated according to modified Baird-Jackson standard.

RESULTS

All patients were followed up from 1.0 to 2.2 years with an average of 1.3 years. Radiographic measurements were detailed as follows: tibiofibular overlap averaged (0.46 +/- 3.56) mm in preoperative and (7.14 +/- 0.62) mm in postoperative; mean total clear space (5.69 +/-0.88) mm in preoperative and (3.28 +/- 0.39) mm in postoperative; medial clear space averaged (5.67 +/- 1.23) mm in preoperative and (3.12 +/- 0.33) mm in postoperative; tibiofibular overlap in mortise view averaged (-0.87 +/- 0.96) mm in preoperative and (2.91 +/- 0.30) mm in postoperative. There was significant difference above data between preoperative and postoperative (P < 0.01). Four cases were confirmed minor tibiofibular diastasis through CT scans during postoperative. The modified Baird-Jackson scoring was from 62 to 98 scores with an average of (86.24 +/- 13.26) score at the final review. Of them, 13 ankles had not pain; 16 ankles reported no instability complaints; 11 ankles gained normal walking ability; 8 ankles could run normally; 11 ankles could return work without any restrictions. Activity of ankle in dorsiflexion, plantar flexion, inversion and eversion were respectively (21.05 +/- 5.00) degrees, (33.57 +/- 5.76) degrees, (19.48 +/- 4.57) degrees and (24.05 +/- 4.86) degrees. Three cases had radiological and clinical manifestations of osteoarthritis, but no breakage of syndesmotic screw in all cases. There were excellent results in 12 cases, good in 2, fair in 4, poor in 3.

CONCLUSION

The treatment for the syndesmosis diastasis with a three-cortices screw fixation in ankle fractures is effective. Good functional outcome can be obtained with anatomical restoration of the tibiofibular syndesmosis. The repair of deltoid ligament is important for stability of the lower tibiofibular syndesmosis. Removal of the screw before weight loading should be performed to avoid possible screw breakage.