PT  - JOURNAL ARTICLE
AU  - Kunihiko Okano
AU  - Kiyoshi Aoyagi
AU  - Ko Chiba
AU  - Satoru Motokawa
AU  - Tomoko Matsumoto
TI  - Bone Mineral Density Is Not Related to Osteophyte Formation in Osteoarthritis of the Hip
AID  - 10.3899/jrheum.100533
DP  - 2010 Dec 15
TA  - The Journal of Rheumatology
PG  - jrheum.100533
4099  - http://www.jrheum.org/content/early/2010/12/12/jrheum.100533.short
4100  - http://www.jrheum.org/content/early/2010/12/12/jrheum.100533.full
AB  - Objective Reports have suggested that bone mineral density (BMD) is higher in patients with osteoarthritis (OA) of the hip than in healthy controls. Various types of OA of the hip caused by osteophyte formation were observed on radiographs during progression to the advanced degenerative stage, and the preoperative type of OA was reported to influence the results of surgical treatment. However, the mechanism underlying the development of different types of OA is still unknown. We measured BMD of patients with hip OA and determined whether higher BMD was observed in patients with osteophyte formation than in those without osteophytes. Methods We measured BMD of the lumbar spine, radius, and calcaneus using dual-energy x-ray absorptiometry in 88 women who were scheduled to undergo total hip arthroplasty for endstage OA. Hips were evaluated for osteophyte formation using Bombelli’s classification; 31 were graded as atrophic type, 30 as normotrophic, and 27 as hypertrophic. BMD at different skeletal sites were compared among the 3 types of OA. Results No significant difference in BMD of the lumbar spine, ultradistal radius, mid-radius, or calcaneus was observed among the atrophic, normotrophic, and hypertrophic types of OA. Conclusion Our data suggest that osteophyte formation is not related to general BMD. Factors other than general bone status, for example the morphology of the hip joint, need to be analyzed to determine the pathomechanism of osteophyte formation in the osteoarthritic hip.