In cultures where people don’t wear shoes these deformities are almost nonexistent.
Claw toes are flexion deformity of the PIP joints and hyperextension of the MTP joints. Hammertoes are flexion deformity of the PIP joints. Mallet toes are flexion deformity of DIP joints.
(Figure: picture of PIP and MTP joint in a claw toe)
These deformities are often due to the 2nd and sometimes the third toe being longer
which gets swished in the shoes.
Due to the shape of these toes and their constant rubbing in the shoes, secondary callosities develop on the PIP joint, at the ball of the toes and at the tip of the toes.
Sometimes clawing of the toes is secondary to peripheral neuropathy.
Conservative treatment involves proper footwear, and application of pads on pressure points. However these cannot correct the deformities and surgery is often needed.
Surgery involves fusion of the PIP joints and soft tissue releases and tendon lengthening. Weil’s osteotomy is used for long metatarsals and involves shortening of the metatarsal head and fixation with special twist-off screws. This reduces the pressure on the balls of the toes and also reduces the length of the toes and makes footwear comfortable. Often 2nd to 5th metatarsal Weil’s osteotomy is done to improve the cascade and prevent transfer metatarsalgia.