A patient develops acute severe pain and inability to weight-bear 3 weeks after uncomplicated total hip replacement. Examination reveals the limb in flexion, adduction and internal rotation. What is the most likely diagnosis?

• A Anterior dislocation of total hip replacement
• B Periprosthetic joint infection with septic arthritis
• C Greater trochanter avulsion fracture
• D Posterior dislocation of total hip replacement ✓

Explanation

The classic position for posterior dislocation of THR is flexion, adduction and internal rotation — identical to the position of native hip posterior dislocation — because the posterior capsule and short external rotators are violated during a posterior approach. Anterior dislocation produces extension, abduction and external rotation. Infection would show systemic signs. Trochanter avulsion presents with a Trendelenburg gait but without acute limb malposition.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.