Does the lumbar spine need to be supported to stabilize the pelvis during total hip arthroplasty in the lateral position?

Correcting pelvic obliquity in the lateral position to improve acetabular component orientation during total hip arthroplasty

BACKGROUND

The acetabular component orientation during total hip arthroplasty (THA) impacts future hip function and early revision. Correcting pelvic obliquity may improve outcomes.

OBJECTIVE

To correct pelvic obliquity in the lateral position by applying a gradienter and plumb during THA using fluoroscopy.

METHODS

Fifty patients undergoing THA were randomized and divided into 2 groups. In controls, acetabular components were placed using traditional methods. In experimental patients, acetabular components were placed after correcting pelvic obliquity. We measured pelvic obliquity and recorded intra-operative and post-operative abduction angles, comparing abduction angle bias between post-operative measurements and intra-operation estimations.

RESULTS

Before correction, the average pelvic obliquity was -1.647∘± 4.512∘ in experimental patients. The average abduction angle in experimental patients was 42.685∘± 3.355∘ postoperatively, differing by 1.962∘± 1.515∘ from intra-operative estimates, while in control patients, it was 44.534∘± 4.844∘ postoperatively, differing by 4.244∘± 3.042∘ from intra-operative estimates. The bias of the abduction angle was much greater in control than in experimental patients (P< 0.05).

CONCLUSION

The pelvic obliquity in the lateral position affects surgeon judgment during THA. By correcting pelvic obliquity with a gradienter and plumb, the abduction angle bias can be reduced.