Comorbidities Determine TKA Pain Years Later

Research into a patient’s comorbidities when they undergo a total knee arthroplasty may explain pain that occurs two to five years later, according to research reported by Lynda Williams, senior MedwireNews reporter. Researchers Jasvinder Singh, M.D. of the University of Alabama, Birmingham, and David Lewallen, M.D., Mayo Clinic College of Medicine, Rochester, Minnesota, found patients who reported pain years after their surgery were also reporting a wide range of comorbidities including heart disease and depression.

In their article in Rheumatology, the researchers wrote, “Research studies should examine whether preoperative and possibly postoperative optimization of management of these comorbidities can potentially reduce the risk of poor pain outcomes after TKA [total knee arthroplasty]. With an increasing volume of TKA in the United States, a better understanding of risk factors for poor outcomes is critical to allow patients and surgeons to have realistic and appropriate expectations of TKA.”

To reach their conclusions, the two reviewed data from the Mayo Clinic Total Joint Registry for knee pain as well as function assessments of primary TKA patients two and five years after their surgery. They also examined the revision records for patients at the same two- and five-year intervals.

Singh and Lewallen found that 94% of patients underwent a TKA because they had knee osteoarthritis, 4% had rheumatoid arthritis, and 2% had other indications. The researchers examined patient records for diagnoses of heart disease, peripheral vascular disease, renal disease, chronic obstructive pulmonary disease, diabetes, connective tissue disease, anxiety, and depression.

Analysis showed that the likelihood of moderate to severe knee pain in primary TKA patients at the two-year check-up was significantly predicted by anxiety, implant fixation, and the patient’s distance from the medical center. At five years, pain in primary TKA patients was significantly predicted by heart disease, depression and anxiety.

For the revision TKA patients, connective tissue disease and depression were significant predictors of moderate-to-severe pain at 2 years, but no comorbidity predicted the outcome at five years, Williams reported.