Hammer Toe M20.40 735.4

synonyms:hammer toe

Hammer Toe ICD-10

• M20.40 - Other hammer toe(s) (acquired), unspecified foot
• M20.41 - Other hammer toe(s) (acquired), right foot
• M20.42 - Other hammer toe(s) (acquired), left foot

Hammer Toe ICD-9

•  735.4 Acquired deformity of toe; other acquired hammer toe

Hammer Toe Etiology / Epidemiology / Natural History

• PIP joint flexion deformity
• Most common lesser toe deformity
• Caused by overpull of the EDL and intrinsic imbalance
• Generally involves the 2nd toe

Hammer Toe Anatomy

Hammer Toe Clinical Evaluation

• Generally complain of painfull callus over the flexed PIP joint and difficulty with shoe wear
• Push-up Test: passive push-up of the metatarsal head corrects the deformity in flexible cases by removing the overactivve extrinsic muscles

Hammer Toe Xray / Diagnositc Tests

•  Consider AP, lateral and oblique foot films. 

Hammer Toe Classification / Treatment

• Flexible  deformity: accomidative footwear, protective padding.  Consider transfer of FDL dorsally over midshaft of prox phalanx.
• Fixed deformity: Resection arthroplasty of the head and neck of the proximal phalanx vs PIP arthrodesis.
• Fixed deformity with MTP joint dislocation:  PIP resection arthroplasty, extensor tendon lengthening, and Weil osteotomy.

Hammer Toe Associated Injuries / Differential Diagnosis

• Mallet-Toe Deformity
• Claw-Toe Deformity
• Crossover second Toe

Hammer Toe Complications

• Nonuion
• Infection
• Painful hardware

Hammer Toe Follow-up Care

Hammer Toe Review References

• Myerson MS, Fott and Ankle Disorders WB Saunders, 2000
• Coughlin MJ, Dorris J, Polk E. Operative repair of the fixed hammertoe deformity. Foot Ankle Int. 2000 Feb;21(2):94-104