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Adult Reconstruction
intermediate
X-Type

THA Dislocation - Instability and Risk Factors

THA Complications

A 78-year-old woman presents to the emergency department with left hip pain following a mechanical fall. She underwent primary THA via a posterior approach 3 months ago for a displaced femoral neck fracture. She has a history of dementia and Parkinson's disease. X-rays confirm posterior dislocation. This is her first dislocation episode. Regarding THA instability and dislocation:

Mark each as TRUE or FALSE

A

Dislocation is the most common early complication after THA and the most common cause of revision wi...

B

The posterior approach has historically higher dislocation rates (2-4%) compared to the direct anter...

C

Component malposition is the cause in fewer than 10% of THA dislocations; a cup abduction angle of 6...

D

The Lewinnek safe zone for acetabular component position is 40 degrees plus or minus 10 degrees incl...

E

Management of first-time dislocation typically involves closed reduction under sedation followed by ...

Answer the questions to see explanations

Click T (True) or F (False) for each option