The effect of 25-oh (HYDROXY) d vitamin levels and bone mineral density on femoral trochlear cartilage thickness in postmenopausal women with knee osteoarthritis

INTRODUCTION AND OBJECTIVES: We aimed to measure the femoral trochlear cartilage thickness of both knees using musculoskeletal ultrasound (US) and to investigate the predictive value of 25-OH (hydroxy) vitamin D and bone mineral density (BMD) on the cartilage thickness in postmenopausal women with knee osteoarthiritis (OA). MATERIALS AND METHODS: The study was included 42 female patients and 21 healthy female volunteers. Age, body mass index (BMI), exercise habits, smoking and laboratory parameters of individuals were recorded. Standing anteropostrieor and lateral knee radiographs of the patients were performed. Radiological grading of knee OA was done by using radiographic Kellgren-Lawrence scale. BMD measurements (gr/cm2) were done for lumbar vertebrae (L1-L4) and left hip using DEXA (Hologic explorer-S/N 90763) merthod. Cartilage thickness, osteophytes, calcification and subchondral bone irregulations were assessed using US equipment with 5-13 MHz linear transducer. We evaluated pain and functional status and quality of life of patients with WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) OA index and SF-36 (short form-36), respectively. RESULTS: There was a positive correlation between 25-OH D vitamin levels and measurements obtained from LIA (left intercondiler area), LLC (left lateral condil), RIA (right intercondiler area). A significant correlation was evident between BMD values of left femoral neck and LLC (left lateral condil), RLC (right lateral condil). The quality of cartilage clarity was better in the control group in both knees. Osteophytes was only found in the patient group, while calcification was not observed in both groups. A positive correlation between the total WOMAC scores and cartilage clarity scores was detected whereas negative correlation between total SF-36 scores and cartilage clarity scores was found. CONCLUSION: Low levels of 25-OH vitamin D adversely affect the femoral cartilage thickness. Results regarding BMD is controversial. Cartilage clarity seems to be very successful parameter to reflect functional status and the quality of life of patients compared to cartilage thickness. However, this result should be supported by further studies because it is the first study in this regard.