What is a hammertoe?
Hammertoe is a bending of one or both joints of the lesser digits (digits 2-5). The digits contract as a result of a muscle imbalance between the tendons on the top and the tendons on the bottom of the toe. Hammertoes can be flexible or rigid in nature. When they are rigid, it is not possible to straighten out the toe by manipulation. Once the deformity becomes rigid surgery may be the only option as far as treatment. Hammertoes become a problem when wearing shoes because the abnormal bending can put pressure on top of the toe developing a corn as a result of rubbing on the shoe. They may also cause a painful callus on the ball of the foot, which occurs as a result of the toe pressing downward on the bone behind the toe. This area then becomes prominent and the pressure of the bone against the ground causes a callus to form. Hammertoes should be addressed early as they tend to slowly get worse with time and frequently flexible deformities become rigid. Hammertoes never get better without intervention.
What causes hammertoes?
Although neuromuscular and congenital pathologies may contribute to lesser toe deformities, ill-fitting shoes along with the aging process are the leading cause. Most people that have a hammer toe may have inherited if from someone in their family before them. The lesser toes contribute to balance and pressure distribution on the foot and when this delicate imbalance between muscles and tendons occurs, deformities such as hammertoes or claw toes can result. There are factors that can increase the speed and severity in which the deformity will develop. For example, a high arched foot causes an uneven pull of the tendons to the toe allowing for buckling of the toes. A hammertoe may result if a toe is too long and becomes cramped when a tight shoe is worn. With a severe bunion deformity the big toe shifts toward the 2nd digit causing the ligament on the bottom of the joint (plantar plate) to stretch out and exacerbate the hammertoe deformity.
Symptoms of hammertoes
Hammertoes are not always painful. In some cases, patients with a very severe hammertoe can have no pain, while someone with a mild hammertoe can have significant pain. These deformities are typically painful when the patient is wearing shoes because there is rubbing and pressure pain over the knuckle. The flexed tips of the toes can develop corns as well as on the top of the toe caused by constant friction against the shoe. A painful callus can form at the ball of the foot as well. Inflammation and redness can also occur. In patients with neuropathy like a lot of our diabetic patients, this can result in infection of soft tissues and bone. If the ligament at the metatarsal begins to tear, patients will note pain in the ball of the foot just behind the toe.
Diagnosis of hammertoes
During physical examination, the physician evaluates the flexibility of the deformity to determine a treatment plan because the surgical options vary based on whether the deformity is rigid or flexible (able to be reduced). Digital x-rays will be obtained in the office and will show the extent of the contracture and will help determine the severity of the deformity.
Roomy, well fitted shoes with a high and wide toe box and a soft sole are the primary treatment. Shoes with high heels or pointed toes should be avoided. If the shoe has room for the prominent bone, there will be less pain and discomfort. Protective pads or sleeves over the dorsal aspect of the toe can be applied to diminish pressure from the toe box of the shoe. Over-the- counter medicated pads are not recommended because they may contain a small amount of acid that can be harmful. Patients with diabetes or bad circulation should never use these products. Hammertoe slings attached to a metatarsal pad and taping of the MTP joint toward a neutral position also can be beneficial, by keeping the toe straight while in shoes taking the pressure off the toe. These kind of braces or straps cannot reverse the deformed joints and bones, they can only help relieve pain while they are used. Corticosteroid injections as well as oral non-steroidal anti-inflammatory medication are sometimes used to help with pain and inflammation. Custom orthotics can also be made to help control the muscle/tendon imbalance; however there is no way to reverse the deformity or to stop a hammertoe from forming or progressing. This is a progressive deformity that will only become worse with time. Calf stretching exercises are also helpful because they can help to overcome part of the muscle imbalance that causes the hammertoe.
Surgery is typically needed when the hammertoe has become more rigid and painful. The goal of surgery is to bring the toe into a corrected position, increase its function, create a pain-free aesthetic result, allow a return to normal shoes and a return to all activities. When a flexible deformity becomes painful and assessed early enough, early correction can be as simple as a simple tendon release in the toe. The recovery is rapid often requiring nothing more than a single stitch. For mild hammertoes a simple removal of half the joint (arthroplasty) is sufficient. There is a fast recovery with this procedure, however there is an increased chance of a recurrence and an unstable "floppy" toe after surgery. This procedure is commonly performed on the 4th or 5th digits. For mild to moderate hammertoes a fusion is commonly performed in digits 2,3, and 4. Any extra skin or callus is removed from the top of the toe and the joint is removed at the level of the knuckle allowing the toe to straighten. The 2 bones (middle and proximal phalanx) are joined together with either a pin or an internal screw, allowing the bones to fuse into one. The screw does not have to be removed, but a pin will need to be removed after 6 weeks or when fusion has taken place. If the toe continues to be elevated, medially or laterally deviated, the tight ligaments at the level of the joint will be released bringing the digit in a straight position. For moderate to severe hammertoes that have a more rigid deformity more procedures may be required in addition to fusion and ligament release in order to keep the digit straight. In addition, a tendon transfer may be needed, which involves one of the tendons that brings the toe downward to be rerouted to the top of the toe. The purpose of this is that it acts as an internal strap in order to keep the toe straight. The post-operative course includes partial weightbearing in a cam walker boot for a minimum of 6 weeks, until fusion occurs. In some severe instances, when the toe is still not fully corrected because the pressure at the level of the toe and the long bone is too great, the long bone may need to be shortened to decompress the joint and allow the toe to move down into the joint. A cut is made at the head of the long bone allowing the bone to slide back and be shortened. The bone is stabilized with a screw in its new position. The recovery is longer with this procedure and the patient needs to be in a non-weightbearing cast for 4-6 weeks.
Complications with this surgery are infection, excessive swelling leading to delays in healing and potential deviation of the toe. If too much bone is removed during surgery, the toe may be a bit floppy.