Association of hemoglobin levels, acute hemoglobin decrease, age, and co-morbidities with rehabilitation outcomes after total knee replacement

Objective: A study was undertaken to assess the association of preoperative and postoperative hemoglobin levels with rehabilitation outcomes, age, and selected co-morbidities Design: Charts of 49 patients admitted to rehabilitation after total knee arthroplasty due to degenerative joint disease were reviewed. Outcome measures included rehabilitation admission and discharge motor FIM (TM) scores, motor FIM gain, and rehabilitation length of stay. Results: Patients with higher preoperative hemoglobin levels had higher rehabilitation admission motor FIM scores (r = 0.38, P < 0.01) and lower motor FIM gains (r = -0.45, P < 0.001). Patients who had higher hemoglobin levels at rehabilitation admission had higher admission motor FIM scores and shorter length of stay. Patients with diabetes had lower preoperative hemoglobin levels. Patients with hypertension had longer length of stay. Older patients had lower admission and discharge motor FIM scores and longer length of stay. Conclusions: Patients admitted to rehabilitation after total knee replacement have the potential to improve motor function, regardless of their preoperative and rehabilitation admission hemoglobin levels and the decrease in hemoglobin levels. However, those admitted to rehabilitation with lower hemoglobin levels, those with lower admission motor FIM scores, those who are older, and those who have hypertension may expect longer hospital stays to reach their functional goals.