Researchers from the Hospital for Special Surgery (HSS) have indicated that while patients selected for bilateral total knee replacement are younger and healthier than those undergoing one-sided surgery, they are becoming sicker and have exhibited an increase in complication rates. Starvros Memtsoudis, MD, PhD, (pictured right) director of critical care services at HSS, New York City, NY, reportedly led the study.

Memstoudis explains that, “Many of the complications that we studied didn’t decrease over time as you would expect with younger patients and better health care, and some of the complications even increased.” Researchers note that elevated levels of obesity may play a role in the complication rates and the increase in total knee replacements.

A recent HSS news release reports that during the study to better explore trends in bilateral total knee replacements, HSS researchers assessed the Nationwide Inpatient Survey, sponsored by the Agency for Healthcare Research and Quality (AHRQ). According to the release, using the AHRQ, which collects data from about 20% of all hospitalizations in the US, researchers spotlighted 258,524 bilateral total knee replacements performed between 1999 and 2008. The data suggests that the number of annual bilateral procedures rose by 75%. In 1999, bilateral procedures accounted for 3.7% of all knee replacement operations and in 2008 they accounted for 6% of the operations. 

The results also suggest that the average age of patients undergoing bilateral knee replacement decreased by 2.5 years from 1999 to 2008. Researchers add that during these years, patients exhibited higher rates of comorbidities, such as neurologic disease, renal failure, liver disease, diabetes, and chronic obstructive pulmonary disease. Memstoudis emphasizes that the study highlights an uphill battle, “because people are getting sicker, despite us attempting to limit the risk by choosing younger people to do these procedures in.”

Researchers add patients stayed in the hospital an average of 5 days after their procedure in 1999 and an average of 4 days in 2008, yet the proportion of discharges to a home or customary residence without home health care decreased at an average rate of 5.5% per year. 

“Patients being selected for the procedure may be getting younger, but they are not getting healthier and maybe that is why we don’t see a drastic drop in complications,” Memstoudis says.

The study appears online in the journal Clinical Orthopaedics and Related Research.

Source: HSS