Knee arthroplasty patients do not lose weight
MedWire News: Total knee arthroplasty (TKA) does not aid weight loss in obese patients with osteoarthritis, study findings suggest.
"Osteoarthritic patients, who need a TKA, usually complain of knee pain as the major reason to forbid them from exercising to lose weight," explain Raheel Shariff and co-workers, from Warrington General Hospital NHS Trust in the UK.
"Weight gain, in turn, worsens the process of osteoarthritis as a vicious cycle."
Obese patients are usually recommended to attempt a trial of weight loss to reduce knee osteoarthritis symptoms before referral for TKA due to the increased risk for surgical complications, and prosthesis loosening and implant failure in obese individuals compared with healthy-weight patients.
However, research has not examined the impact of TKA on body mass index (BMI).
To investigate, the team compared BMI before and 1 year after surgery in 91 patients, aged an average of 67 years, who underwent unilateral TKA with the same prosthesis. The patients were able to walk unaided before their procedure and had not previously undergone TKA.
As reported in the Journal of Orthopaedic Trauma and Rehabilitation, mean BMI did not significantly differ before and after surgery, at 31.08 and 30.11 kg/m2, respectively. Shariff et al note that earlier research showed prosthesis insertion does not significantly alter weight, and that TKA is not associated with an increase in physical activity. "It seems that TKA alone will not help the patients with osteoarthritis of knee to lose weight by improving mobility but just to minimize the symptoms of knee pain," they write.
The team therefore concludes that TKA patients will need additional help to lose weight and improve their cardiovascular and general health.
By Lynda Williams