Iliopsoas Tenotomy Does Not Negatively Affect Hip Flexion Strength in Crowe 3 and 4 Hips Undergoing Total Hip Arthroplasty.

Abstract

Background: In total hip arthroplasty (THA), even if there is a dislocated hip, restoring the anatomical center of rotation increases long-term survival and hip function. Even with a shortening osteotomy, the procedure is still challenging due to soft-tissue tension. Therefore, soft tissue releases such as iliopsoas tenotomy may be necessary. In our study, we aimed to examine the effects of iliopsoas tenotomy on hip flexion and abduction strength in patients who underwent THA with shortening osteotomy for Crowe 3 and 4 hip dysplasia by using a hand dynamometer for measurement.

Methods: The present study examined 27 patients who underwent THA with shortening osteotomy in unilateral Crowe 3 and 4 hips. The patients' hip flexion and abduction strengths were measured with a hand dynamometer preoperatively and in the first year postoperatively.

Results: The average flexion strength of the operated side was less than the nonoperated side before surgery. It also decreased further in the first six weeks. But the strength increased in the 12th week and reached the same level as the non-operated side in the sixth month. The average abduction strength was less than the nonoperated side before the surgery, and it decreased further in the 6th week after surgery. However, the strength increased during follow-ups and reached the non-operated side strengths in the twelfth week.

Conclusions: In conclusion, during THA procedures for highly dislocated hips, releasing the iliopsoas tendon at the level of the minor trochanter to facilitate distalization of the hip center of rotation does not adversely affect hip flexion and abduction strengths.

Level of evidence: Level II.