The COBRA Technique: Treatment of Advanced Hallux Rigidus and Hallux Valgus

The treatment of advanced hallux rigidus or hallux valgus, particularly in a lower-demand population, has traditionally relied on either fusion of the first metatarsophalangeal joint, or resection arthroplasty. A subset of patients may be deemed poor candidates for fusion, either because of poor healing parameters, or the desire to avoid loss of motion of the joint. Traditional resection arthroplasty, with the Keller technique, carries a high complication rate and poor functional results. The Crescentic Oblique Basilar Resection Arthroplasty has been developed to allow residual motion of the metatarsophalangeal joint, while avoiding residual shortening, drift, and transfer metatarsalgia that is associated with the Keller technique. This is achieved with the use of a crescentic saw blade oriented from a dorsal-distal to plantar-proximal direction, which maintains the plantar plate, maintains length, and creates a concentric joint surface.