Orthopedics - Oleksa A.P. 2006

Congenital and Acquired Deformities of the Lower Extremity
Orthopedic Foot Deformities
Hammer Toes

Hammertoe deformities occur As a result of a contracted long extensor and short flexor of the toes due to wearing tight shoes, neuromuscular FOOT imbalance, Connective Tissue weakness, and congenital defects.

There are Three types of hammertoes classified by the number of affected joints.

The first type is a true hammertoe, characterized by extension deformity of the metatarsophalangeal joint and flexion deformity of the proximal interphalangeal joint. The second type is a claw toe, featuring extension deformity of the metatarsophalangeal joint along with flexion deformities of both the proximal and middle interphalangeal joints. The third type, the mallet toe, also involves flexion deformity of the distal interphalangeal joint. The second hammertoe may overlap the first, valgus-deviated toe.

In all three types, the toe is dorsally flexed, forming prominences—especially in the presence of Hallux Valgus—that are subjected to pressure from footwear. Over time, friction leads to painful callosities over the dorsally protruding interphalangeal joint and on the toe pad.

It should be noted that these deformities progress with age and frequently occur alongside valgus deviation of the great toe in patients with Rheumatoid Polyarthritis, myelodysplasia, muscular dystrophy, and hereditary neural amyotrophy (Charcot-Marie-Tooth disease).

Hammertoes can be flexible—which is typically observed in younger individuals—or rigid. Patients complain of calluses and pain in the dorsally prominent interphalangeal joints while walking in shoes.

Physical examination reveals hyperextended proximal Phalanges at the metatarsophalangeal joints and flexed middle phalanges. Calluses are typically present in the area of the dorsally protruding interphalangeal joints. The patient is unable to actively straighten the toes, while passive examination shows an increased range of motion during extension at the metatarsophalangeal joints and restricted mobility at the interphalangeal joints. In cases of osteoarthritis, toe movements are restricted and painful.

Following patient evaluation, standard foot X-rays in two projections and plantograms are performed. The physician must inspect the footwear worn by the patient to assess its wear patterns.

Treatment. Depending on the duration and severity of the toe deformity, conservative or Surgical treatment is applied.

Conservative treatment is used for mild deformities or when patients decline surgery. It includes: 1) eliminating the ROOT cause of the deformity, if possible; 2) applying thermal Procedures and foot baths; 3) trimming hyperkeratotic tissue on corns and managing callosities; 4) passive correction of the deformity; and 5) wearing loose-fitting shoes with soft insoles.

Conservative treatment provides temporary relief, so it must be repeated periodically. For mild deformities, treatment slows down progression, but patients must continuously wear comfortable shoes with soft insoles.

Surgical treatment is indicated for patients with pronounced hammertoes that impair normal daily activities when conservative measures fail. In cases of hallux valgus, hammertoes are corrected simultaneously.

Surgery for hammertoes is performed under anesthesia. An incision is made along the dorsal aspect of the protruding interphalangeal joint, adjacent to the extensor tendon. It is essential to avoid damaging the Blood Vessels located on both sides of the toe. The extensor tendon is isolated, transected in a Z-shape, and retracted, although tendon transection is not strictly mandatory as simple dislocation may suffice.

Next, the collateral ligaments of the joint are isolated and the Joint Capsule is incised, providing access to the articular ends of the phalanges. If the proximal phalanx flexes freely at the metatarsophalangeal joint, resection of the Base of the middle phalanx may be sufficient. The toe is straightened and fixed in a normal position using a Kirschner wire driven transarticular into the metatarsal bone. If the proximal phalanx is markedly hyperextended and rigid, the incision is extended, a dorsal capsulotomy is performed at the metatarsophalangeal joint, and the HEAD is excised. The phalanx is flexed into a normal position, the toe is straightened, and fixation is achieved with a Kirschner wire extending into the metatarsal bone. The end of the wire protruding above the Skin is bent to prevent migration.

If arthrodesis of the proximal interphalangeal joint is chosen, the head of the proximal phalanx is resected, its contact surface is adapted to the resected middle phalanx, and the toe is fixed with a Kirschner wire as described above. We reiterate Structure/19.html">The Importance of avoiding damage to the digital vessels.

The extensor tendon is repositioned to its original site or its ends are sutured, and the wound is closed in layers. A plaster splint is applied.

If interphalangeal joint arthrodesis was performed, the Kirschner wire is removed 4–5 weeks postoperatively; otherwise, it is removed after three weeks, along with the plaster splint. The patient must continue wearing loose closed-toe shoes or sandals for another 2–3 weeks.

Postoperative complications include prolonged toe Swelling, which resolves within one to two months. In such cases, compresses with a 0,25 % dimexide solution and overnight paraffin Applications are used. If infection occurs at the pin insertion site, the wire must be removed prematurely. Any migrating wire must also be removed. Regarding the corn on the toe, it typically gradually diminishes and disappears following surgery.

However, a very painful callosity of the fifth toe, caused by shoe compression, is frequently encountered. Hyperkeratosis most commonly develops on the dorsolateral surface of the proximal interphalangeal joint at the site of the protruding margin of the middle phalanx, especially in the presence of an adducted fifth toe.

In such cases, patients often attempt self-treatment: trimming the calluses, taking warm foot baths, and trying to wear comfortable low-heeled shoes. These measures provide temporary relief, but once the pain becomes unbearable, patients seek medical help.

Surgical treatment is performed under general or regional anesthesia. A dorsal incision is made over the PROJECTION OF THE proximal interphalangeal joint, sparing the corn. The joint is exposed by elevating and retracting the soft-tissue flap, and the lateral prominence along with the exostosis at the base of the middle phalanx is excised. If necessary, the toe is abducted and fixed with a Kirschner wire or an interdigital spacer. The wound is closed in layers.

After suture removal and pin extraction, the patient is prescribed warm foot baths and paraffin applications, and should wear loose shoes until the callus completely disappears.

Hammertoes are frequently associated with flexion contracture of the distal phalanx (mallet toe), accompanied by painful callosities on its plantar surface.

Since conservative treatment for this deformity is ineffective, surgery is recommended. Under anesthesia, the hammertoe deformity is first corrected, followed by a plantar capsulotomy of the distal interphalangeal joint combined with tenotomy of the short flexor of the distal phalanx. The phalanx is extended into a normal position, and the toe is fixed with a Kirschner wire passing through all three phalanges into the metatarsal head. Occasionally, arthrodesis of the distal interphalangeal joint is performed in a functionally advantageous position of the distal phalanx.

During surgery, it is crucial to avoid damaging the digital vessels and the nail matrix. The Procedure is concluded by wound closure and the application of a plaster splint. Postoperative care does not differ from the protocol described above.

In recent years, arthroplasty of the metatarsophalangeal joints (Fig. 222) has become widely used, particularly for hammer toes in patients with rheumatoid Arthritis. These surgical procedures should be considered advantageous and promising.