Hallux rigidus refers to the condition of degenerative arthritis of the first metatarsophalangeal joint (MTPJ) with proliferative osteophyte formation and joint space narrowing leading to decreased range of motion and pain. Capsular interpositional arthroplasty is one technique that may be used to treat end-stage arthritis of the first MTPJ. In the correctly selected patients, it may lead to preservation of first MTPJ motion while affording pain relief.
Special attention should be directed to:
Length of the second metatarsal
Possible transfer lesion
Presence of sesamoid arthritis
First tarsometatarsal instability
Gout and rheumatoid arthritis due to their soft tissue–destructive nature
Nearly Full Contraindications:
High-demand patients (e.g., athletes, dancers) are strongly discouraged from this procedure.
Poor vascular status
CLINICAL/SURGICAL PEARLS AND PITFALLS:
Inspect joint and if greater than 50% of joint cartilage remains, consider proceeding with cheilectomy with or without dorsal (Moberg) closing wedge osteotomy of the phalanx.
Resect 25% of the proximal phalanx with a sagittal saw protecting the extensor hallucis longus and flexor hallucis longus. Take care not to resect too much phalanx because this can lead to “floppy” toe and later deformity.
Transect extensor hallucis brevis tendon approximately 3 cm proximal to the joint. This prevents the capsular tissue from being retracted during gait.
Allograft (gracilus or hamstring) or autograft (plantaris or hamstring) may be used for insufficient capsule. These can be placed into a cavity prepared by use of metatarsophalangeal joint fusion reamers or a bur instead of proximal phalanx resection.
Lengthen extensor hallucis longus if toe sits in an extended position after reconstruction.
Consider second metatarsal shortening osteotomy for patients with long second metatarsal to prevent transfer lesion.
HISTORY/INTRODUCTION/SCOPE OF THE PROBLEM
The first metatarsophalangeal joint (MTPJ) is composed of the dorsal joint capsule, medial and lateral collateral ligaments, the plantar plate/sesamoid/flexor hallucis brevis tendon complex, the first metatarsal head, and the proximal articulating end of the proximal phalanx. First MTPJ arthrosis has been linked to trauma, inflammatory arthridities (rheumatoid arthritis, gout, etc.), and primary osteoarthritis (OA). Associated factors of a long first metatarsal, flat metatarsal head, metatarsus primus elevatus, pronated feet, and hallux valgus interphalangeus are often found in patients with arthritis of the first MTP joint. The condition is bilateral approximately 80% of the time (one side more symptomatic than the other) and affects women more than men. Osteophytes form to stabilize and increase the surface area of the arthritic joint. However, the progression of osteophytes and joint space narrowing on radiographs may or may not correlate with symptoms.
Patients report pain with dorsiflexion activities (high-heeled shoes, running, yoga, etc.) and pain with small toe-box shoes, while radiographs demonstrate progressive proliferation of osteophytes about the joint ( Figs. 36-1 and 36-2 ). If less than 50% of the joint space is remaining, then capsular interpositional arthroplasty is indicated. If greater than 50% of the joint space remains, then consideration should be given to a cheilectomy with or without Moberg osteotomy.
Special attention should be directed to the relative length of the second metatarsal (possible transfer lesion) (see Fig. 36-2 ), hallux valgus, the presence of sesamoid arthritis, and first tarsometatarsal instability as these can be considered relative contraindications. Fusion may be more strongly considered in these cases. High-demand patients (e.g., athletes, dancers) are strongly discouraged from this procedure. Inflammatory arthridities such as gout and rheumatory arthritis are relative contraindications due to their soft tissue destructive nature. Poor vascular status, neuropathy, and infection are absolute contraindications to this procedure.