Defining and Evaluating Claw Toe and Hammertoe Deformity: A Scoping Review and Questionnaire Study

BACKGROUND: This study aimed to provide an overview of the definitions of claw toe and hammertoe deformities as well as the assessment methods used by various specialties to evaluate their presence and severity in both literature and clinical practice. METHODS: A scoping review was conducted using multiple electronic databases to search for articles that contained a definition or assessment method for claw toe or hammertoe deformity. Additionally, orthopedic surgeons, rehabilitation physicians, and podiatrists completed a questionnaire on the definitions and assessment methods they use in clinical practice. RESULTS: Most reported definitions of hammertoe deformity in the literature involved hyperflexion of the proximal interphalangeal joint (PIPJ). Sixteen different definitions were reported. Clinicians varied in their responses: most definitions comprised hyperextension of the metatarsophalangeal joint and hyperflexion of the PIPJ with a varying position of the distal interphalangeal joint. For claw toe deformity, 11 different definitions were found in the literature, and the most common involved hyperextension of the metatarsophalangeal joint with hyperflexion of the PIPJ and distal interphalangeal joint. This was also the most commonly reported definition among clinicians. Quantitative methods for assessing toe deformity were limited, with evaluation relying primarily on visual assessment. CONCLUSIONS: There are a wide variety of definitions and a lack of consensus regarding claw toe and hammertoe deformity in the literature and among various specialty disciplines. Additionally, there are no standardized, validated methods for evaluating the presence and severity of these deformities; observation is primarily used. This hampers effective communication and analysis of toe deformity in clinical practice.