Predicting Outcome of Total Knee Replacement Surgery in Patients With Knee Osteoarthritis

Predicting Outcome of Total Knee Replacement Surgery in Patients With Knee Osteoarthritis: a Prospective Study on the Role of Altered Central Pain Processing and Structural, Functional, Metabolic, Inflammatory and Psychological Factors

Osteoarthritis (OA) is the main cause of pain and disability in elderly. For knee OA, a total knee replacement (TKR) is an effective surgical treatment, and the majority of patients report substantial pain relief and functional improvement following surgery. However, 20-40% of patients undergoing TKR are dissatisfied with postsurgical outcome. Even after revision, some patients keep complaining of persisting pain.

In this study, the investigators will examine putative prognostic factors on the basis of the biopsychosocial model. Besides several psychological factors (measured with questionnaires), the investigators will assess structural impairments (such as radiographic severity of OA), functional impairments (muscle weakness and proprioceptive deficits), anesthetic procedures, immediate postoperative pain management, metabolic factors (body composition and hemoglobin A1c), inflammatory factors (C-Reactive Protein) and the investigators also will examine the role of altered central pain processing (CPP) (primary and secondary mechanical hyperalgesia, mechanical temporal summation, thermal primary and secondary hyperalgesia, endogenous pain modulation).

With a longitudinal study design, this study will explore which factors are predictive of poor outcome in knee OA patients after TKR. Moreover, the interrelationship between CPP, structural, functional, metabolic, inflammatory and psychological factors, and the clinical expression of knee OA (pain, symptoms, physical performance and quality of life) will be investigated.

Further research on the role of the aforementioned putative prognostic factors on postsurgical outcome could contribute to better management of these patients, since these factors may be particularly important for patient-tailored treatment.

Inclusion Criteria:

• Knee OA patients >40 years awaiting TKR surgery. Both men and women of all ethnical backgrounds are included.

Exclusion Criteria:

• Patients with diagnosis of neurological/ systemic diseases, possibly impacting pain
• Patients who are not capable of understanding and speaking Dutch
• Revision surgery