Dorsal Cheilectomy for Hallux Rigidus

Hallux rigidus refers to limited dorsiflexion of the first metatarsophalangeal (MTP) joint as a result of dorsal osteophyte impingement.

Plantarflexion is typically not limited but may be restricted if a large dorsal osteophyte is present.

In advanced stages, global arthrosis of the first MTP joint is present.

ANATOMY

The first MTP joint is supported medially and laterally by collateral ligaments that provide medial–lateral stability (FIG 1A).

The plantar aspect of the joint consists of the following:

The sesamoid complex, including attachments of two slips of the flexor hallucis brevis, which invest the sesamoids (FIG 1B)

The plantar plate, a thick fibrous band of tissue that additionally invests and supports the sesamoids. The flexor hallucis longus runs between the sesamoids (FIG 1C).

The dorsal aspect of the joint includes the capsule, the attachment of the extensor hallucis brevis to the base of the proximal phalanx, and the extensor hallucis longus within the extensor hood.

PATHOGENESIS

Congenital hallux rigidus (tends to be bilateral)

Concomitant hallux interphalangus

A flat or chevron-shaped MTP joint. This tends to concentrate stresses more centrally.

Abnormal joint biomechanics

Trauma to the dorsal articular cartilage, either by a direct blow or repetitive microtrauma

Cartilage damage secondary to inflammatory reactions from gout or inflammatory arthritis

NATURAL HISTORY

Abnormal stresses across the MTP joint—through alterations of biomechanics, increased concentration of dorsal cartilage stresses and wear, inflammatory reaction, or direct cartilage injury—result in reactive dorsal osteophyte and marginal osteophytes. If those stresses are not alleviated or corrected, more global arthritic changes may evolve.

PATIENT HISTORY AND PHYSICAL FINDINGS

Sagittal range of motion is assessed (FIG 2). Pain is typically elicited with extremes of motion, secondary to dorsal impingement, and with plantar motion traction on the dorsal osteophyte.

A positive grind test indicates more global arthritis, a relative contraindication for cheilectomy.

Note presence or absence of tenderness with the sesamoid complex examination.

IMAGING AND OTHER DIAGNOSTIC STUDIES

Standing anteroposterior (AP), lateral, and oblique radiographs are required (FIG 3A,B).

The joint space may be obliterated by osteophytes on the AP radiograph, so the oblique radiograph may provide a better view of the retained joint surface.

The AP radiograph is useful to evaluate medial and lateral osteophytes, and the lateral radiograph will reveal the presence of metatarsus elevatus, and the extent of the dorsal osteophyte.

Axial sesamoid view will provide additional information about the sesamoid complex.

Magnetic resonance imaging is helpful if osteochondral defect of the metatarsal head is suspected (FIG 3C).

DIFFERENTIAL DIAGNOSIS

Arthrosis (advanced hallux rigidus)

Osteochondral defect

“Turf toe,” sesamoid complex injury

Gout

NONOPERATIVE MANAGEMENT

Nonoperative treatment consists of the institution of nonsteroidal anti-inflammatory drugs (NSAIDs), accommodative orthotics, and, rarely, physical therapy if gait abnormality is present.

Accommodative orthotics are designed to restrict sagittal range of motion of the hallux and to redistribute weight-bearing stresses across the first MTP joint with the use of a Morton extension.

If sesamoid inflammation is present, protective padding is added around the sesamoids and the orthotic is welled out under the sesamoids to provide stress relief.

SURGICAL MANAGEMENT

Preoperative Planning

Preoperatively, patients are assessed for whether they are appropriate candidates for cheilectomy or for fusion if there are symptoms of more global arthritis of the first MTP joint.

Cheilectomy is performed for predominantly dorsal arthritic symptoms and for failure to respond to nonoperative means of treatment, as outlined in the previous section.

Positioning

Preoperatively, patients receive a regional ankle block consisting of a 1:1 mixture of 0.5% bupivacaine and 1% lidocaine, without epinephrine.

Intravenous antibiotics are administered in the holding area, 30 to 45 minutes before the procedure.

The patient is placed supine on the operating room table, with the foot at the distal edge of the table to allow for easier fluoroscopic access.

The foot, ankle, and lower leg are prepped and draped to the lower calf with the use of a leg holder.

Approach

The first MTP joint is approached dorsally, starting distally from the midportion of the proximal phalanx, and extending proximally 3 cm proximal to the joint.