A hammer toe is a common foot deformity where one of the smaller toes develops an unnatural shape, causing it to curl instead of lying flat. This condition often affects the second, third, or fourth toe. Understanding the specific visual markers of this contracture is the first step in identifying the condition and distinguishing it from other similar foot conditions.
The Characteristic Bend
The defining visual feature of a hammer toe is the pronounced contracture, or buckling, at the proximal interphalangeal (PIP) joint, which is the middle joint of the toe. This bending causes the toe to rise up at the knuckle, creating an inverted “V” shape when viewed from the side. The overall appearance resembles the head of a hammer, with the toe’s tip pointing downward toward the ground.
This abnormal position forces the middle segment of the toe to visibly protrude upward, often termed the “raised knuckle.” Below this prominent bend, the distal segment of the toe is angled downward, making the toe’s tip appear compressed against the surface it rests upon. The joint space at the PIP joint may look visibly narrowed due to the sustained flexed position.
Hammer toes are classified by their mobility, which indicates the stage of the condition. A flexible hammer toe can still be manually straightened by applying gentle pressure. In contrast, a rigid hammer toe is fixed, meaning the joint cannot be passively moved back into a straight position. The rigid form appears more severely deformed and cemented in its buckled state.
Associated Visual Changes
The primary bend frequently leads to secondary changes on the skin, typically caused by friction against footwear or the ground. The raised knuckle, which is the most prominent point of the deformity, is a common site for the development of corns. These corns appear as small, dense, circular areas of hardened skin that form a cone shape directly over the apex of the bent joint.
Calluses, which are broader and flatter areas of thickened skin, may also be visible on the top of the bent joint or on the very tip of the toe where it presses into the shoe or floor. The body creates this thickened tissue as a protective response to constant rubbing and pressure. The skin surrounding the buckled joint may also show signs of irritation, appearing slightly red or inflamed due to repetitive friction.
Hammer Toe Versus Similar Deformities
Distinguishing a hammer toe from other common toe deformities depends on identifying the location of the bend. A hammer toe is defined by the contracture occurring specifically at the middle joint (PIP joint). The toe’s joint closest to the foot (metatarsophalangeal or MTP joint) and the joint nearest the nail (distal interphalangeal or DIP joint) are typically straight or only slightly affected.
A mallet toe, by comparison, involves a bend only at the DIP joint (the joint nearest the toenail). This gives the tip of the toe a compressed appearance while the rest of the toe remains straight. A claw toe involves a more complex visual presentation, featuring a bend at both the middle (PIP) and end (DIP) joints. Additionally, the MTP joint at the base of the toe often appears hyperextended, causing the entire toe to curl downward into a claw-like shape.