THE EFFECT OF ORIENTATION OF THE ACETABULAR COMPONENT USING TRANSVERSE ACETABULAR LIGAMENT AS GUIDE ON FUNCTIONAL OUTCOMES FOLLOWING PRIMARY TOTAL HIP ARTHROPLASTY.

Background: Our aim is to investigate the acetabular component positioning using TAL & its functional outcomes in primary THA as assessed by modified Harris Hip Score (mHHS). Materials and Methods: 30 patients were selected randomly in this prospective study after getting clearance from the research and ethical committee in a Tertiary care centre in North India. All Total Hip Arthroplasty surgeries were performed using direct lateral Hardinge's approach & used TAL was used as the guide for positioning the acetabular cup. Acetabular version and inclination were assessed using a CT scan and functional outcome was evaluated using mHHS. Results: The mean absolute position of the acetabular cup in our study population included 15.3±5.85 degrees of anteversion and 42.7±5.31 degrees of inclination angle. 86.67% of patients had both acetabular version and inclination within Lewinnek's "safe zone" with only a single case of postoperative dislocation. The correlation between the cup version and mHHS was significant (p-value=0.028) whereas the correlation between acetabular inclination and mHHS was insignificant (p-value=0.29. Conclusion: TAL is a reliable, inexpensive and patient-specific intra-operative anatomical landmark for the placement of acetabular components with efficacy comparable to that of a mechanical alignment guide (MAG). [ABSTRACT FROM AUTHOR]