Unipolar, Bipolar, or THA — Need to Read Past the Surface

Twists and turns on the way to a good, practical message about a big topic

What’s the Claim?

After controlling for numerous patient-level (but no surgeon-related) covariates, a comparative study from the large, well-maintained Kaiser hip fracture registry found:

  • Patients with hip fractures who had a unipolar or bipolar hemiarthroplasty had higher rates of subsequent revision than did patients who received a THA (hazard ratio 2.2 [95% CI 1.5 to 3.1] and 1.9 [95% CI 1.3 to 2.8]), but
  • If they were over the age of 80 or had an ASA score higher than III (reflecting more-severe comorbid conditions), they had no differences in revision risk based on whether a unipolar, bipolar, or THA was used.

We think this can be interpreted a few different ways, all of them interesting and practical.

How’s It Stack Up?