Hypermobility of the first ray: a critical review of the literature.

The authors provide a detailed review of the available literature regarding first ray sagittal plane direction and range of motion with special emphasis on whether or not hypermobility of the first ray can truly be supported as a definable clinical entity. They also describe a novel clinical test for assessing sagittal plane instability of the first ray. The authors believe that this test, when combined with previously defined clinical tests, helps to identify those few patients that would benefit from an arthrodesis procedure of the medial pillar of the foot for the treatment of the hallux valgus deformity.