RECURRENT POST-TRAUMATIC DISLOCATION OF THE HIP 632 TIlE JOURNAL OF BONE AND JOINT SURGERY

Recurrent dislocation of the hip joint in the absence of a predisposing acetabular defect is rare: so far as we have been able to determine, it has been reported in only eleven adults and eleven children. Sullivan, Bickel and Lipscomb (1955) listed the predisposing causes as acetabular fracture, congenital dysplasia of the hip, sepsis and paralysis, and described an additional case in which the phenomenon was noted after an apparently spontaneous dislocation due to “a simple fall”. To the list of contributory causes, it appears that an additional factor may now be added, namely inadequate immobilisation of the hip after reduction, with consequent incomplete healing of the posterior capsular structures. In support of this assumption, we report two hitherto unpublished cases. CASE REPORTS Case 1-A man aged twenty-one years sustained posterior dislocation of the right hip when he fell while walking on wet grass in November 1967. He was admitted under our care on the day of the injury. He expressed surprise at the ease with which the joint had slipped out, FIG. 1 FIG. 2 Case 1. Figure 1-Radiograph showing second posterior dislocation of the right hip joint. Figure 2