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Adult Reconstruction
intermediate
X-Type

Hip Instability After Arthroplasty

Hip Arthroplasty

A 72-year-old woman presents 3 weeks after primary total hip arthroplasty with acute hip pain after standing from a low chair. Radiographs confirm posterior hip dislocation. This is her first dislocation. CT scan shows the cup is in 55 degrees of inclination with 35 degrees of anteversion. She has been following posterior hip precautions. Regarding hip instability after total hip arthroplasty:

Mark each as TRUE or FALSE

A

Dislocation is a leading cause of revision after primary THA, occurring in 1-5% of primary cases; ri...

B

Component positioning is critical: the "safe zone" (Lewinnek) for acetabular cup is 40±10 degrees in...

C

Dislocation is rare after THA (less than 0.1%); component position does not affect stability; the di...

D

Management of first dislocation: closed reduction under sedation or anesthesia; assess for component...

E

Surgical options for recurrent instability: component revision if malpositioned; larger femoral head...

Answer the questions to see explanations

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