The relation between regional and subchandral bone mineral density and femoral cartilage thickness on the patients the early and late stage knee osteoarthritis

The purpose of this study is to compare the medial and lateral subchondral bone mineral density of the femur measured by Dual Energy X- ray Absorptiometry (DEXA) and the femoral cartilage thickness measured by the ultrasonography of the patients with the early and late stage knee osteoarthritis and to examine the relations between them. 100 patients who consulted with knee pain and diagnosed osteoarthritis according to American College of Rheumatology criteria were included to the study. According to the Kellgren Lawrence classification, the stage 1 and the stage 2 patients were considered the early stage and the stage 3 and the stage 4 patients were considered the late stage knee osteoarthritis. 50 of the patients with knee osteoarthritis were at the early stage and 50 of them were at the late stage. The Body Mass Index (BMI) of all the patients were calculated by measuring their height and weight and their walking durations of 100 meter destination were measured. For the global evaluation of the pain on the patients for the patients and the doctors Visual Analog Scale (VAS), for the evaluation of function and disability Western Ontario and MCMaster Universities Osteoarthritis Index (WOMAC), Lequesne Algofunctional Knee Scale, for the evaluation of the life quality general health criteria Short Form-36 (SF-36) and Nottingham Health Profile (NSP), for evaluation of the anxiety and depression state The Hospital Anxiety and Depression Scale HAPS) were used. Kellgren-Lawrence (K-L) radiological staging scale was used to evaluate the both-side knee graphies of all patients. DEXA was used to measure the patients' lumbar region (L2-4), left femoral region(femur neck, trochanter, wards and total), both knees subchondral regions (medial and lateral subchondral bone mineral density of the femur (sBMD) was measured by using a subchondral surface having 10 mm height) bone mineral density(BMD), ultrasoundgraphy (USG) was used to measure femural cartilage thickness of both knees ( medial and lateral and intercondylar). 100 meter walking duration and all (VAS) scores of the patients with late stage knee osteoarthrisis were found significantly higher than those of the patients with early stage knee osteoarthrisis. The (WOMAC) index total scores and subscale ( pain, morning stiffness and physical activity)scores of patients with late stage knee osteoarthrisis were found significantly higher than those of the patients with early stage knee osteoarthrisis. The NSP scores, Lequesne Algofunctional Knee Index total scores of the late stage patients group were found significantly higher than the early stage patients group. Similarly, the SF-36 physical function, role limitations and general health perception scores of the late stage patients group were found statisticaly significant lower than the early stage patients group. There wasn't a significant difference between all femur, lumbar and BMD values of both knees and knee femur cartilage thicknesses measured by USG of the early stage and the late stage patients. The BMI values of the late stage patients were found significantly higher than the early stage patients. A positive relation was found between the BMI values and lumbar, femur and BMD of all patients. In the correlation analysis of all patients, a positive relation between the right knee, the left knee, total femoral cartilage thickness and femoral BMD values was found. As a result, in this study it is found that the BMI rise of the patients with osteoarthritis has a protective effect against the osteoporosis. But it should not be ignored that obesity is an important risk factor for the knee osteoarthritis. Moreover, it can be stated that increased femur BMD values may have a protective effect against cartilage loss on the knee joint. Finally, treatment of accompanying osteoporosis is beneficial to prevent cartilage loss. Key words: Osteoarthritis, osteoporosis, femoral cartilage thicknesses, ultrasound