Iliac crest pain syndrome in low back pain: frequency and features.

A specific regional pain syndrome, the iliac crest pain syndrome (ICPS), defined by typical local tenderness over the medial part of the iliac crest, was recently found in hospital referred patients with chronic low back pain (LBP). To validate the prevalence of ICPS in different patient settings and to present quantitative data about associated clinical features, we prospectively studied 204 consecutive patients with LBP from a general practice (n = 40), an occupational health service (n = 124) and a rheumatology clinic (n = 40). ICPS was found in 53, 33 and 58%, respectively (41% of the total group). Associated clinical features were localized pain (in 73% of patients with ICPS) and typical pain reproduction by movements of the lumbar spine (64%) or hips (53%), leg raising (37%) and the heel-fall test (24%), in contrast to 2-12%/sign in patients with LBP without ICPS. These observations demonstrate that ICPS is present in a considerable percentage of all patients with LBP and is easy to differentiate clinically from patients with other forms of LBP.