[Fractures of the anterior rim of the distal part of the tibia. Apropos of a series of 38 cases].

PURPOSE OF THE STUDY: Fracture of the anterior rim of the distal tibia is a rare injury. This fracture seems less serious than other pilon fractures but its treatment is often difficult and didn't give better results. The aim of this study was to describe problem we dealed with and to suggest solutions in order to improve long term results.

MATERIAL: The study included 38 cases, treated in 5 Paris district trauma centers, with a minimal follow-up of 6 months. All patients were asked for clinical and radiological review between september 92 and march 93 ; otherwise, latest review datas were used.

METHODS: Authors suggest a radiological classification based upon type, width and talus anterior displacement. Different surgical procedures were performed for 33 cases (screw, plate, external fixation) ; conservative treatment was used 5 times (non weight bearing plaster cast). Anatomical reconstruction was analysed. Functional results scoring system included pain, global abilities and ankle range of motion. Ankle arthritis was rated according to 1992 SOFCOT scoring system at 1 and 3 year follow-up.

RESULTS: Follow-up ranges from 6 months to 11 years (average 28 months). 55 per cent of cases were lost for review with 1 year mean follow-up. 45 per cent of patients were recently tested with 4 year mean follow-up. Three ankles had joint fusion 6 to 18 months after trauma. Functional result was poor. For 35 ankles analysed 1 out of 4 remained totally painless (9 cases), 1 out of 2 had a good function (20 cases) and 1 out of 3 normal X-rays (12 cases). Arthritis was found for 2 ankles out of 3 after one year follow-up (16 cases out of 23). Loss of reduction or incomplete reconstruction seemed the most important point (13 cases out 38, 13 cases after 35 surgical procedures).

DISCUSSION: Many patients didn't get a long term evaluation, and this study has no statistical value. Anyway, function loss was always early on a weight bearing joint. A perfect and stable reconstruction gives a higher rate of good result (11 out of 14). Analysis of cases with anatomic imperfection leads to recommendations: fixation of separation fracture, even undisplaced, bone grafting to correct impaction, appropriate use of external fixation for neutralization.

CONCLUSION: Better results should come from a better analysis of the bone lesions : separation, impaction or mix fracture. This analysis leads to appropriate surgical procedure which give back a stable and anatomic distal tibia. External fixation can be usefull for immobilization ; this can't avoid open reduction and internal fixation of the fracture. Bone grafting can be useful for impaction fracture.