ORLANDO, Fla. — Research presented here highlighted patient and surgeon factors associated with the development of motor nerve palsy after primary total hip arthroplasty.
“We did find characteristics that are significantly associated with developing motor nerve palsies. It was a younger age than 50 [years], a start time of later than 4 pm, a history of lumbar disease — and that lends to the theory there may be a double crush on the nerve, one compression at the lumbar spine and one at the hip — a smoking history, and there was a definite association with the surgeon,” Edwin P. Su, MD, said during his presentation at the Current Concepts in Joint Replacement Winter Meeting. “These factors can help you consul your patients, perhaps stratify your patients, maybe change things and do patients who are higher risk earlier [in the day].”
To understand the risk factors of motor nerve palsy, Su and his colleagues at Hospital for Special Surgery studied 39,056 primary total hip arthroplasties (THAs) performed at the hospital during a 15-year period.
“We identified 93 motor nerve palsies for overall incidence of 0.24%,” Su said.
Edwin P. Su
The investigators matched each case with two control patients who underwent THA during the same week, but did not develop the condition. In addition to examining patient characteristics that could be linked with the risk of nerve palsy, researchers studied surgeon factors, such as fellowship training, years in practice and volume. They also studied radiographic findings, such as the grade of arthritis, center of rotation and off-set.
A multivariate analysis revealed patient age younger than 50 years and a history of smoking were among the factors significantly associated with an increased risk for nerve palsy.
“Interestingly, the day of the procedure — later in the week — was associated with a higher odds ratio,” Su said. “In terms of the timing of the day, 4 pm or later had a significantly higher odds ratio 4.7-times higher, and a history of spinal stenosis and lumbar spine disease were the strongest associated factors with an odds ratio of almost eight-times greater risk of nerve palsy. We also found an effect of the surgeon.” – by Gina Brockenbrough, MA
Su EP. Paper #38. Presented at: the Current Concepts in Joint Replacement Winter Meeting; Dec. 9-12, 2015; Orlando, Fla.
Disclosure: Su reports he has stock options for OrthAlign Inc. and receives consulting fees for the hip advisory board of Smith & Nephew Inc.