Dose-Related Effects of Steroid on the Experimental Arthritis in Rabbits

OBJECTIVE: To investigate dose-related effects of repeated intraarticular steroid injection on the experimental arthritis. METHOD: Twenty-four adult male rabbits received Zymosan A into their right knee joint for experimental arthritis. After a week, they were injected with 2 mg (group I; n=9), 10 mg (group II; n=7) or 20 mg (group III; n=8) triamcinolone acetonide into their right knee weekly interval for 4 weeks. We measured weekly changes of the weight and the mediolateral diameter of both knees for the calculation of edema index. 99mTechnetium pertechnate (99mTc) uptake measurement were performed before the first steroid injection and a week after the final steroid injection. All rabbits were sacrificed and histologic examinations of their proximal tibia were performed. RESULTS: A progressive weight loss and changes of edema index were evident for all rabbits (p0.05). In the histological findings, fibrillation-frayings and fissures of the surface were similar in all rabbits, but loss of nuclear stains and cyst formations were increased prominently in group III than group I (p<0.05). CONCLUSION: Low-dose repeated steroid intraarticular injections are safe and effective treatment in arthritis though no definite evidence of chondroprotection, and high-dose steroid injections accelerate degeneration of the arthritic cartilage.

The Effect of Chronic Low Back Pain on Bone Mineral Density and Trunk Muscle Strength in Women

OBJECTIVE: To evaluate (1) the effect of chronic low back pain on bone mineral density, and (2) the effect of chronic low back pain on trunk muscle strength in women. METHOD: Subjects were 118 women patients (ages of 28~65 years) suffering from chronic low back pain more than three months and control groups were 218 healthy women (age of 26~72 years). We measured bone mineral density (BMD) at the lumbar spine and proximal femur using Dual X-ray absorptiometry and trunk muscle strength using Cybex 660 dynamometer. RESULTS: There was no significant difference between groups in lumbar spine BMD, in proximal femur BMD, or in trunk flexor muscle strength. However, trunk extensor muscle strength was reduced significantly in patient group. Trunk extensor muscle peak torque was 64.69+/-18.48 Nm in the patient group and 73.84+/-22.50 Nm in the control group in 30 degrees/sec, and 58.65+/-18.59 Nm in the patient group and 65.68+/-20.28 Nm in the control group in 60 degrees/sec. CONCLUSION: The results suggest that chronic low back pain does not affect the BMD. However, it causes trunk extensor muscle weakness; therefore, trunk extension exercise will be help to the patients with chronic low back pain.

Parkinson's Disease and Osteoporosis

Parkinson's disease(PD) is characterized clinically by bradykinesia, rigidity, tremor, and disturbance of posture and equilibrium. A higher incidence of fractures in PD patient has been reported, however the studies of musculoskeletal complications in PD have been negligible. The purposes of this study were to investigate the incidence of osteoporosis and spinal compression fracture in PD patients and to evaluate whether the incidence were affected by the severity of PD. Bone mineral density(BMD) in 21 patients(5 males and 16 females) with idiopathic PD was measured by dual energy X-ray absorptiometry(DXA) and compared with an age adjusted control group(32 females). The patients were divided into two groups according to the Hoehn and Yahr(H-Y) stage as mild or severe and the BMD was compared. Simple x-ray studies of thoracolumbar spine were performed to find out the presence of spinal compression fractures. The results showed that the BMD of PD patients was significantly lower than control subjects. The PD patients with high H-Y stage(severe group) had lower BMD scores with no statistical significance. The spinal compression fractures were noted mainly at mid-thoracic area and thoraco-lumbar junction. Spinal t-score in patients with a compression fracture was significantly reduced. No significant correlation exists between back pain and a compression fracture.

Trunk Muscle Strength and Bone Mineral Density in Women

OBJECTIVE: The purpose of this study was to investigate a correlation between the muscle strength of trunk and bone mineral density (BMD) in women. METHOD: A total of 218 healthy women participated in the study. Their age ranged from 26 to 72 years. Dual X-ray absorptiometry was used to measure the BMD of lumbar spine and the trunk muscle strength was assessed by a Cybex NORMTM system. Under the standard criteria of World Health Organization for the dual X-ray absorptiometry analysis, we divided spine T-score into three groups(group 1: osteoporosis, group 2: osteopenia, and group 3: normal). RESULTS: The data revealed a siginificant correlation (r= 0.455, p=0.0001) between the age and BMD of lumbar spine. Trunk extensor muscle strength revealed 56.27+/-18.08 Nm (mean+/-SD) in osteoporosis group, 72.84+/-21.69 Nm in osteopenic group, and 77.90+/-22.28 Nm in normal group. Trunk flexor muscle strength was 82.73+/-23.30 Nm in osteoporosis group, 86.00+/-19.77 Nm in osteopenic group, and 98.91+/-18.29 Nm in normal group. CONCLUSION: These results indicated that the trunk extensor muscle was weaker than the flexor muscle in osteoporotic group. As the bone mineral density reduced, the strength of both trunk extensor and flexor decreased. However the weakness of trunk flexor occurred at the earlier stage of osteoporosis than the weakness of trunk extensor.