Is postoperative function after hip or knee arthroplasty influenced by preoperative functional levels?

Area of Science:

• Orthopedic Surgery
• Rehabilitation Medicine
• Health Outcomes Research

Background:

• Preoperative functional status significantly impacts patient outcomes following total hip and knee arthroplasty.
• Identifying patient subgroups with low preoperative function is crucial for managing expectations and optimizing surgical planning.

Purpose of the Study:

• To evaluate functional outcomes in hip and knee arthroplasty patients with low preoperative functional scores.
• To compare outcomes between patients with worse versus higher preoperative functional levels.

Main Methods:

• Prospective cohort study of 127 unilateral total hip and knee arthroplasty patients.
• Assessment using Western Ontario and McMaster University Osteoarthritis Index (WOMAC), Short Form 36 (SF-36), and Quality of Well-Being index.
• Patients stratified into 'worse functioning' (WOMAC >= 51) and 'higher functioning' (WOMAC < 51) groups preoperatively.

Main Results:

• The worse functioning group consistently reported poorer outcomes on the Quality of Well-Being index, SF-36 (function and social scores), and WOMAC (total and pain scores) across all time points (P < .0001).
• The most substantial improvements for all variables in both groups occurred within the first year after surgery.
• Patients with severe/extreme preoperative functional impairment showed worse 3-year outcomes compared to those with better preoperative function.

Conclusions:

• Preoperative functional impairment is a significant predictor of poorer long-term outcomes after hip and knee arthroplasty.
• While arthroplasty improves function, patients with severe preoperative limitations experience less benefit and sustained poorer outcomes.
• Targeted interventions and realistic expectation setting are vital for patients undergoing arthroplasty with low preoperative functional levels.