Atlantoaxial (C1-C2) facet joint osteoarthritis: a distinctive clinical syndrome.

Osteoarthritis of the atlantoaxial facet joints was identified radiologically in 27 patients, and these comprised 4% of all outpatients with osteoarthritis or degenerative disease of the spine seen during a 36-month period. These patients had a clinical syndrome which differed from those seen in patients who have subaxial degenerative disease of the spine or myofascial cervical pain. Occipital pain, occipital trigger points, crepitus in the occipital region, and a rotational head tilt deformity (in 13 patients, usually associated with collapse of 1 of the lateral masses [facets]), were the major features of this distinctive syndrome.