A patient is reported who developed a fistula between the hip and the caecum 39 years after arthrodesis of her hip. She presented with a painful right hip and radiographs showed that the Smith-Petersen nail used for arthrodesis had moved up through the acetabulum and into the pelvic cavity. The nail was removed but within a week a fistula which discharged alimentary contents had developed between the hip and the caecum. The patient was treated conservatively, and three weeks later the fistula had closed.

At the apex of an idiopathic scoliotic curve there is a greater proportion of "slow twitch" muscle fibres in multifidus on the convex as compared to the concave side. To determine whether this represents a primary muscular imbalance relevant to the aetiology of idiopathic scoliosis or merely a secondary change, the lengths of multifidus on opposite sides of the curve were measured. Multifidus is shorter on the convex side. This is consistent with the theory of primary muscular imbalance, in which the more tonically acting muscle with its higher proportion of "slow twitch" fibres contracts and shortens as the deformity is produced. The paradox of multifidus being shorter on the convex rather than on the concave side is explained by consideration of its action.