Objective
To investigate the prevalence and clinical features of diffuse idiopathic skeletal hyperostosis (DISH) in patients with dorsal back pain. Method: A total of 229 patients (119 men and 110 women) with dorsal back pain were included. Medical records including age, sex, chief complaints, medical history, physical findings, laboratory data, and musculoskeletal radiographs were reviewed retrospectively. Results: Twenty-seven (11.8%, by Resnick's criteria) and thirty-eight (16.6%, by Julkunen's criteria) of the 229 patients were diagnosed with DISH by thoracic spine radiographs. A significant increase of risk with age was observed (Resnick's criteria: odds ratio 1.10, 95% CI 1.05∼1.16, p＜ 0.001, Julkunen's criteria: odds ratio 1.08, 95% CI 1.04∼1.12, p＜0.001). Male sex (Resnick's criteria: odds ratio 2.65, 95% CI 1.01∼6.95, p=0.048, Julkunen's criteria: odds ratio 2.87, 95% CI 1.27∼6.59, p=0.011) and inflammatory pain (Resnick's criteria: odds ratio 7.76, 95% CI 2.69∼22.33, p＜0.001, Julkunen's criteria: odds ratio 3.84, 95% CI 1.55∼9.47, p=0.004) showed higher risk for development of DISH. Mean body mass index of patients with DISH were higher in all age groups, and they showed higher prevalence of DM and hyperlipidemia than general population. Conclusion: Patients with dorsal back pain showed higher prevalence of DISH than previous results with random samples. Aging, male sex and inflammatory pain might be a risk factor for development of DISH. Also, obesity, DM and hyperlipidemia might be strongly related with DISH. (J Korean Acad Rehab Med 2009; 33: 564-571)

Objective
To investigate the differences in clinical and radiologic features between HLA-B27 positive ankylosing spondylitis (AS) and HLA B27 negative AS. Method: Ninety-nine consecutive patients who were suspected as AS in initial diagnostic process were studied. HLA-B27 was examined with microlymphocytotoxicity method in all patients. A radiologist and a physiatrist re- read plain pelvis radiographies of all patients. Difference in onset age and C-reactive protein (CRP) depending on HLA B27 status and an association between HLA B27 status and clinical and radiologic features were tested. Results: Sacroiliitis (≥bilateral grade 2) was identified in 63 of 77 patients with HLA B27 and 7 of 22 patients without HLA B27 through the re-reading process. Ten percent of definite AS was HLA B27 negative AS. Five of 22 patients without HLA B27 were diagnosed as diffuse idiopathic skeletal hyperostosis. There was a significant association between sacroiliitis (≥bilateral grade 2) and HLA B27 (p＜0.05) in re-reading process. No significant difference was found in onset age, and CRP depending on HLA B27 status. No significant association was noted between HLA B27 and gender, clinical and radiologic features. Conclusion: HLA B27 is useful in diagnosing AS in patients with clinical features of AS and sacroiliitis (≥unilateral grade 1). None of clinical and radiologic parameters are associated with HLA B27 status. It does not make difference in onset age of AS. To make a more concrete conclusion, a study of a much larger number of HLA B27 negative AS patients will be necessary. (J Korean Acad Rehab Med 2007; 31: 220-227)