Hallux Rigidus

Hallux rigidus is degenerative arthritis of the first metatarsophalangeal joint (MTPJ), characterised by progressive loss of dorsiflexion, dorsal osteophyte formation, and pain. It is the most common arthritic condition of the foot and the second most common disorder of the hallux after hallux valgus. Understanding the grading systems, non-operative management hierarchy, and surgical options — particularly the decision between cheilectomy and arthrodesis — is central to the orthopaedic curriculum.

• Incidence: affects approximately 2.5% of adults over 50 years; bilateral in approximately 30%; slight female predominance in some series; prevalence increases significantly with age
• Pathophysiology: primary OA of the first MTPJ; articular cartilage loss → subchondral sclerosis → osteophyte formation → dorsal impingement → progressive loss of dorsiflexion; the dorsal osteophyte impinges during push-off, which requires approximately 65° of MTPJ dorsiflexion for normal gait
• The hallux requires 65° of dorsiflexion for normal walking and 90° for running — when this is lost, patients compensate by supinating the foot, rolling off the lateral forefoot, avoiding push-off, or flexing the knee early; these compensatory gait changes produce secondary problems including metatarsalgia, lateral column overload, and knee/hip pain
• Aetiology: primary (idiopathic) most common; secondary causes include previous trauma (turf toe, first MTPJ fracture), osteochondral defect, hallux valgus surgery, gout, rheumatoid arthritis, and osteonecrosis
• Risk factors: long first metatarsal (Morton foot), pes planus, hallux valgus, and prior injury to the first MTPJ

Multiple grading systems exist for hallux rigidus. The Coughlin and Shurnas classification is the most widely used and validated, integrating clinical and radiological features.

• Symptoms: dorsal first MTPJ pain; stiffness; swelling; shoe-fitting difficulty (toe box friction against dorsal osteophyte); altered gait — lateral foot supination during push-off
• Physical examination: palpable dorsal osteophyte; restricted passive and active dorsiflexion; grind test — axial compression plus rotation of the proximal phalanx on the metatarsal head; positive if pain throughout arc of motion = Grade 3–4 with mid-ROM cartilage loss; if pain only at extremes = Grade 1–2, suitable for cheilectomy
• Assess: dorsiflexion in degrees (neutral and weightbearing), crepitus, dorsal osteophyte size, sesamoid tenderness, hallux interphalangeal joint (IPJ) hyperextension compensating for MTPJ stiffness
• Footwear: shoe toe box height and width; patient often wears open-toed shoes or rocker-bottom shoes to offload the joint

• Weight-bearing AP, lateral, and oblique foot radiographs: essential for grading; assess joint space, osteophyte burden, sesamoid position and involvement, and Meary line
• MRI: for soft tissue assessment, osteochondral lesions, sesamoid abnormality, and pre-operative planning when diagnosis is uncertain
• CT: pre-operative planning for complex cases; assesses sesamoid position and size of osteophytes more precisely than plain film
• Blood tests: ESR, CRP, uric acid — if inflammatory arthritis or gout suspected as secondary cause; HLA-B27 and RF if seronegative/seropositive arthropathy suspected

• Footwear modification: wide toe box, stiff-soled shoe, rocker-bottom sole — reduces MTPJ motion during gait; the most effective non-operative intervention
• Morton extension insole: rigid carbon fibre or polypropylene extension under the first ray to the tip of the hallux — prevents MTPJ dorsiflexion; loads the IPJ instead; effective for mild-moderate hallux rigidus
• NSAIDs: short-term pain relief; not disease-modifying
• Intra-articular corticosteroid injection: USS-guided; short-term benefit for acute inflammatory flares; not repeated more than 2–3 times; may temporarily allow continued activity while awaiting surgery
• Physiotherapy: manual mobilisation of the first MTPJ; sesamoid mobilisation; strength training of flexors; some evidence for benefit in early disease

The fundamental surgical choice is between cheilectomy (joint-preserving) and arthrodesis (joint-sacrificing). This decision is primarily determined by the grade of disease and the presence or absence of mid-ROM pain (grind test).

• Cheilectomy: excision of dorsal osteophytes and up to 30% of the dorsal metatarsal head articular surface; increases MTPJ dorsiflexion; preserves the joint; indication — Grade 1–2 hallux rigidus; pain only at the extremes of motion; negative or equivocal grind test; good results in approximately 80–90% at 5–10 years for Grade 1–2; progression to arthrodesis required in approximately 15–20% at 10 years
• Arthroscopic cheilectomy: minimally invasive alternative; equivalent results to open; faster recovery; increasingly performed
• Moberg osteotomy: proximal phalangeal closing wedge dorsal osteotomy; plantarflexes the proximal phalanx, converting plantar flexion to effective dorsiflexion of the hallux; extends the functional range achievable at push-off; often combined with cheilectomy in Grade 2 disease where cheilectomy alone provides insufficient gain in functional dorsiflexion
• First MTPJ arthrodesis: gold standard for Grade 3–4 hallux rigidus — reliably eliminates pain; provides durable and predictable long-term outcome; fusion position critical: 10–15° of dorsiflexion relative to the floor in the sagittal plane (not relative to the first metatarsal), 15–20° of valgus, neutral rotation; union rate approximately 90–95%; excellent patient satisfaction; allows return to most activities
• Fusion position assessment intraoperatively: stand the patient`s foot on a flat board — the hallux nail should be just off the ground (0.5–1 cm) to confirm correct dorsiflexion; excessive plantar flexion causes interphalangeal joint hyperextension and callosity; excessive dorsiflexion causes hallux tip and IPJ pain
• Implant arthroplasty (Cartiva SCI, hemi-arthroplasty): interpositional or resurfacing implants for Grade 2–3 disease in patients who refuse fusion or have specific activity demands (high heels); evidence weaker than for arthrodesis; Cartiva SCI (synthetic cartilage implant) — FDA approved, 5-year data shows non-inferiority to arthrodesis in selected patients; revision to arthrodesis if implant fails

• Cheilectomy in Grade 3 disease: opinions divided — some surgeons advocate cheilectomy even in Grade 3 as a staging procedure before arthrodesis; advocates argue it provides meaningful symptom relief and delays fusion; others argue it is inappropriate in Grade 3 due to mid-ROM cartilage loss; the grind test is the key determinant — positive grind (pain throughout ROM) = proceed to arthrodesis rather than cheilectomy, even in younger patients
• Failed cheilectomy: conversion to arthrodesis is the standard salvage — technically straightforward if adequate bone stock preserved; avoid excessive metatarsal head resection during cheilectomy (no more than 30% of articular surface) to preserve bone for potential future arthrodesis
• Hallux rigidus arthrodesis position and activities: patients frequently ask about activities after arthrodesis; gardening, walking, cycling, swimming, and low-impact sport are all compatible; high heels are usually not possible; some patients manage running; heavy sport is limited; counsel patients pre-operatively about realistic expectations; IPJ may develop arthritic change over time from increased demand
• First MTPJ arthrodesis and IPJ: long-term follow-up shows progressive IPJ arthritis in approximately 20–30% at 10 years — direct result of compensatory IPJ motion; assess IPJ pre-operatively; severe pre-existing IPJ disease may influence the decision toward implant arthroplasty over arthrodesis

• Hallux requires 65° dorsiflexion for walking, 90° for running — loss drives compensatory supination and lateral column overload
• Coughlin-Shurnas Grade 3–4: <10° dorsiflexion; significant joint space loss; constant pain; Grade 4 = pain in mid-ROM
• Grind test positive (pain throughout arc of motion) = Grade 3–4 = arthrodesis; grind test negative (pain only at extremes) = Grade 1–2 = cheilectomy
• Cheilectomy: remove dorsal osteophytes + up to 30% dorsal metatarsal head; Grade 1–2; 80–90% good results; 15–20% progress to arthrodesis at 10 years
• Arthrodesis position: 10–15° dorsiflexion relative to floor, 15–20° valgus, neutral rotation; hallux nail just off the ground intraoperatively
• Moberg osteotomy: proximal phalangeal dorsal closing wedge; converts plantar flexion ROM to functional push-off; used with cheilectomy in Grade 2
• Morton extension insole: rigid extension under first ray; prevents MTPJ dorsiflexion; effective conservative measure for mid-grade disease
• Failed cheilectomy: convert to arthrodesis; do not resect >30% metatarsal head at index procedure — preserve bone stock for revision
• Cartiva SCI: synthetic cartilage implant; non-inferior to arthrodesis in 5-year data; for Grade 2–3 patients refusing fusion; revision to arthrodesis if fails
• Post-arthrodesis IPJ arthritis: 20–30% at 10 years; from compensatory IPJ loading; counsel patients pre-operatively