Outcome of non-operative treatment of patients with primary osteoarthritis of the knee at Moi Teaching and Referral Hospital, Eldoret, Kenya

Abstract

Background: Primary osteoarthritis (OA) is a chronic disorder of synovial joints in which there is progressive softening and damage of articular cartilage and ultimately joint destruction. In Kenya,70% of OA cases are due to knee OA. Treatment is nonoperative for mild to moderate cases and surgical for severe cases. Few studies have been done locally to determine non-operative treatment methods and their outcome. The study aims to address this gap. Objectives: To determine outcome of non-operative treatment of primary OA of the knee at Moi Teaching and Referral Hospital (MTRH). Methods: A hospital based descriptive prospective study was carried out at MTRH orthopaedic clinic involving patients managed for primary OA of the knee between 1st January 2017 to 30th June 2018. Those included were all new adult patients with primary OA of the knee. Patients with secondary OA of the knee and rheumatoid arthritis were excluded. Study participants enrolled were 72 but 4 were lost to subsequent follow up. Information on osteoarthritic indicators of pain, stiffness and limitation in function was collected using radiographs, questionnaires and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) at 0, 3 and 6 months. Non-operative treatment types and changes in symptomatology with different prescribed treatment methods in the clinic was then followed. Collected data was analysed and presented in form of figures, tables and graphs. Results: Median age of the respondents was 64 years (IQR 56,69years). Majority were female (80.6%). Most respondents were employed in the informal sector (68. 1%).Most respondents were of normal body mass index (41.7%). Hypertension was the most common co-morbidity seen in 12.5% of all patients. Obesity was present in 23.7% of cases. The most affected knee was right in 45.8% of the respondents, followed by left (33.4%) then bilateral (20.8%). Most respondents had duration of symptoms of less than 5 years (82.0%). A total of 69 patients had abnormal x-ray findings. Treatment administered consisted of lifestyle modification in all patients, non-steroidal antiinflammatory drugs (NSAIDS) in 94.1% of respondents, opioids (2.9%) and steroids (2.9%). Glucosamine/chondroitin sulphate was given as an adjunct treatment in 49.9% of respondents. Other adjunct treatments given were knee bracing and physiotherapy. Most patients improved over the 6 months of the study. Only 19.4% of patients had mild symptoms (WOMAC score 0-32 points) at the beginning of the study which increased to 85.3% at 3 months, then dropped to 67.6% at 6 months. Moderate symptoms (WOMAC score 33-65 points) were observed in 75.0% of respondents at the beginning of the study, which dropped to 13.1% at 3 months and 30.1% of respondents at the end of the study. Severe symptoms (WOMAC score greater than 65 points) were observed in 5.6% of respondents at the beginning of the study and 1.5% of respondents at 3 and 6 months. There was no significant association between OA of the knee with BMI and hypertension (p-value 0.881 and 0.335 respectively) Conclusion: Primary OA of the knee had high occurrence in elderly female patients at MTRH, with good treatment outcome after 6 months of combined non-operative treatment methods, with NSAIDS and glucosamine/chondroitin sulphate being the main drugs used. Recommendation: Standard protocols for non-operative treatment of primary knee OA should include NSAIDS. Control and preventive measures against the modifiable risk factors for primary OA of the knee should be encouraged. Further research on long term outcome of primary OA of the knee.