Objective: To evaluate the inflammatory involvement of cervical interspinous bursae in patients with polymyalgia rheumatica (PMR) using magnetic resonance imaging (MRI).
Methods: Twelve consecutive, untreated new patients with PMR were investigated. Five patients with fibromyalgia, 2 patients with cervical osteoarthritis and 6 patients with spondyloarthritis with neck pain served as controls. MRI of the cervical spine was performed in all 12 PMR case-patients and in 13 control-patients. Two of the 4 PMR patients with pelvic girdle pain also had MRI of the lumbar spine.
Results: MRI evidence of interspinous cervical bursitis was found in all patients with PMR, and in 3 patients with fibromyalgia, in 2 with psoriatic spondylitis and 1 with cervical osteoarthritis. A moderate to marked (grade >2 on a semiquantitative 0-3 scale) cervical bursitis occurred significantly more frequently in patients with PMR than in control-patients (83.3% compared with 30.7%, p=0.015). In all patients and controls with cervical bursitis the involvement was found at the C5-C7 cervical interspaces. MRI of the lumbar spine showed lumbar interspinous bursitis at the L3-L5 lumbar interspaces in the 2 patients with PMR and pelvic girdle pain examined.
Conclusions: Cervical interspinous bursitis is a likely basis for discomfort in the neck of patients with PMR. The prominent inflammatory involvement of cervical bursae supports the hypothesis that PMR is a disorder of prominent involvement of extra-articular synovial structures.