Wheeless' Textbook of Orthopaedics
this procedure allows long toe flexors to behave like intrinsic muscles producing active plantar flexion at MP joints & extension at IP joint; - indicated for flexible hammer toes and claw toes;

East Lancashire Foot and Ankle Hyperbook

A deformity with hyperextension of the MTP joint and flexion of the IP joints is usually referred to as a claw toe.
When the DIP joint is straight or extended the deformity is usually referred to as a hammer toe.
However, some papers use the terms hammer and claw toe in confusing, ill-defined and contradictory ways. Always check what a paper means by these terms (they often don't tell you!).

Definition Hammer, claw, and mallet toe surgery refers to a series of surgical procedures performed to correct deformed toes. Purpose There are three main forms of toe abnormalities in the human foot: hammer toes, claw toes, and mallet toes. A hammer toe, also called contracted toe, bone spur, rotated toe, or deformed toe, is a toe curled as the result of a bend in the middle joint. It may be either flexible or rigid, and may affect any of the four smaller toes. The joints in the toe buckle due to tightening of the ligaments and tendons, which points the toe upward at an angle. The patient's shoes then put pressure on the prominent portion of the toe, leading to inflammation, bursitis, corns, and calluses. Mallet toes and claw toes are similar to hammer toes, except that different joints on the toe are affected. The joint at the end of the toe buckles in a mallet toe, while a claw toe involves abnormal positions of all three joints in the toe. Encyclopedia of Surgery: A Guide for Patients and Caregivers Expert

Although this condition can be conservatively accommodated, in certain instances surgical procedures are a favourable option. The objective of this paper is to discuss the current surgical approaches used to correct a hammer toe deformity. The author will also discuss the aetiology and pathomechanics of a hammer toe with a brief overview of conservative therapy.

Wheeless' Textbook of Orthopaedics
term describes abnormal flexion posture of PIP joint of one of lesser 4 toes;
- the hammer toe deformity is similar to the curly toe deformity but is not malrotated;
- flexion deformity of PIP may be fixed or supple;
- w/ severe hammer toe deformity, MP joint may go into hyperextension (distal joint usually stays supple);

AAOS Online Service Fact SheetHammer toe Highly Reputable

Author: Anthony Watson, MD, Assistant Professor of Orthopaedic Surgery, Department of Orthopedic Surgery, Foot and Ankle Program, Allegheny General Hospital
Hammertoe deformity is the most common deformity of the lesser toes. It primarily comprises flexion deformity of the proximal interphalangeal (PIP) joint of the toe, with hyperextension of the metatarsophalangeal (MTP) and distal interphalangeal (DIP) joints
Synonyms and related keywords: claw toe, toe deformity, foot deformity, deformed toe, deformed foot lesser-toe deformity, deformity of the lesser toes, Morton foot, Morton's foot

The big toe, called the Hallux, is made up of two small bones called phalanges. This condition presents as a cocking up of the big toe at the joint between these two small bones. Expert

Hammertoes are a contracture of the toes as a result of a muscle imbalance between the tendons on the top and the tendons on the bottom of the toe.

A mallet toe is a fixed or flexible deformity of the distal interphalangeal (DIP) joint of the toe. Pain or callosity may be the presenting complaints when the DIP joint of the toe has abnormal flexion, either fixed or flexible.

Wheeless' Textbook of Orthopaedics
refers to flexion posture of DIP;
- may occur as isolated disorder or along w/ hammer toe deformity;
- this deformity occurs most often in 2nd toe, which is frequently the longest & which is impinged in a tight fitting shoe, causing DIP flexion;
- mallet toe is common in diabetics with peripheral neuropathy, and end corns in this population may become infected