Question

A patient fell down from bicycle and started having pain around hip, shortening of limb and attitude was flexion, adduction, internal rotation (IR) of hip

• A. Anterior dislocation
• B. Transcervical fracture
• C. Posterior dislocation
• D. IT Fracture

Hint:

Remember the classic limb position: flexion, adduction, and internal rotation points to posterior displacement of the femoral head.

Answer 1

The Correct Option is C

Step 1: Identify the clinical findings. The patient has:
- Trauma (fell from bicycle)
- Pain around the hip
- Shortening of the limb
- Attitude of the limb: Flexion + Adduction + Internal Rotation of the hip

Step 2: Apply the mnemonic for hip dislocation attitudes.
- Posterior dislocation: Flexion + Adduction + Internal Rotation (FAIR) -- the head dislocates posterior to the acetabulum; the iliopsoas, gluteus medius, and short external rotators pull the limb into this position.
- Anterior dislocation: Extension + Abduction + External Rotation -- the femoral head dislocates anteriorly toward the obturator foramen or iliac area.

Step 3: Understand the mechanism. Posterior dislocation of the hip typically occurs with dashboard injury (knee hitting dashboard in a head-on collision) or falls with the hip flexed and adducted. Forceful internal rotation, adduction, and flexion (or axial loading in this position) drive the femoral head posteriorly through the weakest part of the posterior capsule.

Step 4: Eliminate other options. Transcervical fracture (intracapsular neck of femur fracture) presents with shortening and external rotation, not internal rotation. Intertrochanteric (IT) fracture also causes shortening with external rotation. Anterior dislocation presents with abduction and external rotation.

Conclusion: Flexion + Adduction + Internal Rotation = Posterior dislocation of the hip.