Prospective comparative evaluation of intraoperative joint stability and component placement between posterior approach to hip and its quadriceps coxae sparing modification for primary hip arthroplasty.

BACKGROUND

Efforts at minimizing the propensity of posterior approach of hip for post-operative dislocation after total hip arthroplasty have been a subject of continual research. We comparatively evaluated the posterior approach to hip and its quadriceps coxae sparing (QCS) modification with regard to joint stability and component placement.Questions/Purposes: (1) Does sparing of Quadriceps Coxae tendons vis a vis their sectioning in posterior approach help in achieving better intraoperative stability? (2) Does sparing of Quadriceps Coxae tendons come in the way of adequate surgical exposure sufficient to place hip components accurately? (3) Does sparing of Quadriceps Coxae tendons result in better early functional outcome?

METHODS

Seventy-two patients requiring THA were enrolled prospectively and randomized into two groups: group A (posterior approach) and group B quadriceps coxae sparing (QCS) approach. They were compared for intraoperative joint stability, accuracy of component placement, duration of surgery, blood loss, any event of hip dislocation, and functional outcome.

RESULTS

QCS approach resulted in better intraoperative hip stability as the hips tolerated a higher value of 43.5±3.5⁰ mean internal rotation (at 90⁰ of flexion and 20⁰ of adduction) in this group versus a mean value of 33.5±5.5⁰ in posterior approach group (p < 0.01). No significant difference was observed for femoral version, acetabular inclination, and acetabular version in the two groups (p > 0.05). There was no difference between the two groups in terms of duration of surgery, intraoperative blood loss, and functional outcome at one year (p > 0.05). No event of hip dislocation was observed in QCS approach, whereas, one such event happened in the posterior-approach group.

CONCLUSION

Preservation of the QC tendons improves the intraoperative stability of THA and they do not cause any hindrance in the exposure required for optimum component placement.