We have compared the results at a mean follow-up of 13 years (11 to 14) of two groups of supination-external rotation type-4 fractures of the ankle, in one of which there was a fracture of the medial malleolus and in the other the medial deltoid ligament had been partially or completely ruptured.

Of 66 patients treated operatively between 1993 and 1997, 36 were available for follow-up. Arthroscopy had been performed in all patients pre-operatively to assess the extent of the intra-articular lesions. The American Orthopaedic Foot and Ankle Society hind-foot score was used for clinical evaluation and showed a significant difference in both the total and the functional scores (p < 0.05), but not in those for pain or alignment, in favour of the group with a damaged deltoid ligament (p < 0.05). The only significant difference between the groups on the short-form 36 quality-of-life score was for bodily pain, again in favour of the group with a damaged deltoid ligament. There was no significant difference between the groups in the subjective visual analogue scores or in the modified Kannus radiological score.

Arthroscopically, there was a significant difference with an increased risk of loose bodies in the group with an intact deltoid ligament (p < 0.005), although there was no significant increased risk of deep cartilage lesions in the two groups.

At a mean follow-up of 13 years after operative treatment of a supination-external rotation type-4 ankle fracture patients with partial or complete rupture of the medial deltoid ligament tended to have a better result than those with a medial malleolar fracture.

We have evaluated prospectively the arthroscopic findings in acute fractures of the ankle in 288 consecutive patients (148 men and 140 women) with a mean age of 45.6 years. According to the AO-Danis-Weber classification there were 14 type-A fractures, 198 type B and 76 type C.

Lesions of the cartilage were found in 228 ankles (79.2%), more often on the talus (69.4%) than on the distal tibia (45.8%), the fibula (45.1%), or the medial malleolus (41.3%). There were more lesions in men than in women and in general they were more severe in men (p < 0.05). They also tended to be worse in patients under 30 years and in those over 60 years of age. The frequency and severity of the lesions increased from type-B to type-C fractures (p < 0.05). Within each type of fracture the lesions increased from subgroups 1 to 3 (p < 0.05). The anterior tibiofibular ligament was injured with increased frequency from type-B.1 to type-C.3 fractures (p < 0.05), but it was not torn in all cases. While lateral ligamentous injuries were seen more often in type-B than in type-C fractures (p < 0.05), no difference was noted in the frequency of deltoid ligamentous lesions.

Our findings show that arthroscopy is useful in identifying associated intra-articular lesions in acute fractures of the ankle.