To establish the incidence of early dislocation following primary total hip arthroplasty performed through a direct lateral approach when no post-operative restrictions on patient positioning or mobilization were imposed.

499 primary total hip arthroplasties performed in 483 patients between October 1997 and July 2000 were studied prospectively. Surgery was performed through a direct lateral (Hardinge) approach with the patient in a supine or lateral position according to surgeon preference. An Exeter femoral stem with a 26mm head (Howmedica) and an Ogee socket (Depuy) were both cemented. Post-operatively abduction pillows were not used. Patients were specifically advised both pre- and post-operatively by their surgeon, nurses and physiotherapist that no restrictions were placed on their mobilization. They were encouraged to move in any way that they found comfortable and adopt any position they chose. They were allowed to sleep in their usual position and bathe or shower normally.

Mean patient age was 72 (range 35–95). 304 patients (61%) were female. The grade of operating surgeon was consultant in 326 (65%) cases, staff grade in 122 (25%) and specialist registrar in 51 (10%). 284 (57%) operations were performed with the patient placed in the lateral position.

No patients were lost to follow-up. There were three dislocations within six weeks of surgery (defined as ‘early’), a rate of 0. 6%. All were reduced closed and managed conservatively. One hip dislocated for a second time eleven days later but every patient subsequently achieved stability without further intervention. There were no late dislocations.

Our results suggest that a very low early dislocation rate can be achieved when performing primary hip arthroplasty through a direct lateral approach without the need to impose restrictions on post-operative mobilization which patients often find intrusive.