A hammertoe deformity involves a contracture of buckling of one or more of the lesser toes not involving the big toe. Each toe is connected to the foot at the joint by and ligaments and a joint capsule. The toe itself has 3 bones and 2 joints. The deformity is located at the joint where the toe connect to the rest of the foot at its corresponding metatarsal. The first bone of the toe called the proximal phalanx will be contracted upwards (dorsal) while the rest of the toe at the next joint will point downward (plantar). This is then seen as a deformity.
Lesser toe deformities largely can be hereditary. There are also several outside factors than can contribute to the contractures. The major culprit is an imbalance of the muscles and tendons that control the motion of the toe. When the tendon that pulls the toe upward is not as strong as the one that pulls it downward against the ground there is an imbalance of power against the toe. This will make the toe buckle over time leading to the deformity. If the deformity persists it can become rigid and harder to correct. Patients that have a high arched (pes cavus) foot type can have an increased chance of hammertoes occurring. Those patients with bunion deformities will find the 2nd toe elevating and becoming hammered in order to make room for the big toe that is moving towards it. Some patients will damage the ligament that holds the toe in place at the bottom of the joint connecting the toe and the foot. When this ligament (plantar plate) is disrupted or torn, the toe will float upward at this joint.
|Picture showing patient with hammertoe of the second digit.|
|X-ray showing hammertoe of the second digit.|
Pain is caused by the toe constant friction over the top of the main joint of the toe. This is the apex of the deformity. The skin in this area will become irritated and inflamed and painful over time. Callus formation can ensue causing even more pain over time. It may also be difficult to fit into some shoe gear due to the extra space the toes require when deformed. In many cases there will be pain on the ball of the foot over the metatarsals along with callus formation. This is due to the fact that the toes are not functioning properly and not touching the ground as they should during the gait cycle. This then leaves the ball of the foot to take on the brunt of the ground forces, as they were not built to do so this causes chronic pain to the ball of the foot.
Clinical observation of the toe is made to assess which part of the toe is involved in the deformity. It will also need to be determined if the hammertoe is flexible (able to be reduced) or rigid. Plain x-rays will also be needed to determine the extent of the contracture. An examination of the entire foot will be needed to find the root cause of the deformity.
Conservative treatment is limited to accommodation of the deformity. Shoe gear with a wider toe box and higher volume will cause less friction to the toes. There are some toe braces and strapping techniques that can take some of the pressure off the toes during gait. Custom molded orthotics can redistribute the forces through the tendons that control the toe, lessening the pain and the extent of the deformity in some cases. The calluses on the toe and the ball of the foot can be shaven every so often to reduce some pain and pressure, although they will return due to the constant deformity. These measures will not correct the deformity.
Surgical correction of the deformity is needed to bring the toe into a corrected position and to increase its function. Correction of the hammertoes is a simple outpatient surgery with limited downtime. The best option is to fuse the deformed and contracted digit in a straight position. This limits the need for future surgery and deformity return.
In certain cases, a removal of a small area of bone in the deformity area will decrease pain and limit the need for a surgical waiting period that is found with fusions. Although the toe is not as stable as with a fusion, in certain cases, an arthroplasty is the best option for some patients.
|X-ray after correction of hammertoe.|
There is often no need for a pin to stick out the tip of the toe which may be a source for infection and rigid fixation with a screw or absorbable pin allows for rapid healing and early weight on the foot and nothing sticking out of the skin.