Efficacy of Intramuscular Injection of Calcitonin on Pain Functional Status of Patients with Knee Osteoarthritis

BACKGROUND: Recently, increased attention has been paid to calcitonin for the management of osteoarthritis (OA) regarding its metabolic properties for bone turnover and cartilage. OBJECTIVES: This study was designed to assess the efficacy of intramuscular calcitonin injection in the functional status of individuals suffering from knee OA. METHODS: A total of 40 eligible cases with OA were randomly assigned into intervention and control groups. At baseline, pain intensity and functional ability were evaluated based on the Numeric Rating scale (NRS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaires. Both groups were prescribed with AcetaGel (500 mg) and piroxicam (0.5% topical gel) every 8 hours as needed, and the patients were instructed about conservative treatments and lifestyle modifications. In the case group, the patients received calcitonin (50 IU/mL solution for injection; Aburaihan Pharmaceutical Co., Iran) intramuscularly (gluteal muscle) once a week for 4 consecutive weeks. One month after the last dose, the patients were evaluated based on NRS and WOMAC questionnaires. RESULTS: Demographic data did not show any statistically significant difference. A total of 40 cases (male and female) with mean age values of 53.10 ± 5.28 and 54.55 ± 5.26 years were included in the case and control groups, respectively. The mean body mass index values of the case and control groups were 27.45 ± 1.57 and 27.15 ± 1.53 kg/m(2), respectively. After 1 month of treatment with calcitonin, significant improvements were observed in NRS outcomes (P < 0.001). The total WOMAC score was also statistically improved (P < 0.001). CONCLUSIONS: The findings of the present study revealed that the weekly administration of 50 IU calcitonin for 28 days could significantly improve physical ability and pain intensity in OA patients.