Hammer Toes

Hammer toe is the most common lesser toe deformity, characterized by PIPJ flexion with neutral DIPJ and MTPJ, affecting the 2nd toe in 80% of cases due to hallux valgus pressure and intrinsic muscle imbalance. The flexibility test (plantarflex ankle to relax FDL) is the critical examination determining surgical approach: flexible deformities respond to soft tissue procedures (FDL tenotomy, Girdlestone-Taylor transfer), while rigid deformities require bone surgery (PIPJ arthroplasty or arthrodesis). Always assess MTPJ stability with drawer test, as subluxation requires concurrent Weil osteotomy. Surgical correction achieves 80-90% good outcomes with proper deformity classification and procedure selection.

Hammer Toe is the most common lesser toe deformity, accounting for approximately 80% of all lesser toe pathology. It predominantly affects the 2nd toe due to its length (often longest ray) and relationship with hallux valgus.

Epidemiology

• Prevalence: 2-20% of adult population
• Gender: Women affected 4-5x more than men (footwear)
• Age: Peak 40-60 years
• Location: 2nd toe in 80% of cases
• Bilateral: 40% have bilateral involvement

Anatomy

• PIPJ: Proximal interphalangeal joint - site of primary deformity
• Flexors: FDL (flexor digitorum longus), FDB (flexor digitorum brevis)
• Extensors: EDL (extensor digitorum longus), EDB (extensor digitorum brevis)
• Intrinsics: Interossei, lumbricals - flex MTPJ, extend IPJs

Pathophysiology

• Muscle Imbalance: FDL/FDB overpull relative to extensors
• Intrinsic Weakness: Loss of intrinsic function → PIPJ flexion
• Shoe Wear: Tight toe box → toe flexion adaptation
• Hallux Valgus: 2nd toe crowded, forced to flex
• Inflammatory Arthritis: Joint destruction, subluxation

Aetiology

• Footwear: High heels, narrow toe box - most common
• Hallux Valgus: Associated in 50-75% of cases
• Long 2nd Metatarsal: Increased pressure
• Inflammatory Arthritis: RA, psoriatic
• Neurological: Diabetic neuropathy, CMT, CVA (usually claw)
• Trauma: Compartment syndrome, crush injury

History

• Pain: Dorsal PIPJ (shoe rubbing), tip of toe, under metatarsal head
• Callus/Corn: Dorsal PIPJ, tip of toe, interdigital
• Cosmesis: Crooked toe appearance
• Shoe Wear: Difficulty finding comfortable shoes
• Progression: Initially flexible → becomes rigid over time
• Hallux: Associated bunion symptoms

Physical Examination

Examination Technique

1. Standing Assessment

   • Observe toe position weight-bearing
   • Check for associated hallux valgus
   • Assess arch, hindfoot alignment

2. Seated Examination

   • Flexibility Test: Most critical exam finding
     • Plantarflex ankle (relaxes FDL)
     • Attempt to correct PIPJ deformity
     • If corrects = Flexible
     • If fixed = Rigid

3. MTPJ Assessment

   • Drawer Test: Grasp toe, attempt to sublux proximally
   • Positive = MTPJ instability (plantar plate injury)
   • Assess MTPJ ROM

4. Callus/Skin

   • Dorsal PIPJ: From shoe pressure
   • Tip of toe: From ground contact
   • Interdigital: From adjacent toe pressure

5. Neurovascular

   • Capillary refill
   • Sensation (diabetic neuropathy common)

Classification Systems

Coughlin Classification - Lesser Toe Deformities:

• Type I: Flexible deformity, reducible
• Type II: Semi-rigid, partially reducible
• Type III: Rigid, fixed deformity
• Type IV: Rigid with MTPJ subluxation/dislocation

Dhukaram Classification:

• Grade 1: Flexible, correctable
• Grade 2: Rigid PIPJ, flexible MTPJ
• Grade 3: Rigid PIPJ and MTPJ
• Grade 4: With MTPJ dislocation

Differential Diagnosis

Imaging

Weight-Bearing Radiographs:

• AP View: MTPJ alignment, subluxation, joint space
• Oblique View: PIPJ deformity, osteophytes
• Lateral View: Degree of flexion, PIPJ arthritis

Radiographic Assessment

• MTPJ subluxation (proximal phalanx displaced dorsally)
• PIPJ joint destruction/arthritis
• Associated hallux valgus angle
• Metatarsal length assessment
• Bone quality (inflammatory arthritis)

Special Investigations

• HbA1c: If diabetic neuropathy suspected
• Inflammatory Markers: ESR, CRP if inflammatory arthritis
• Nerve Conduction Studies: If neurological cause suspected (CMT)

Surgical Complications

Prevention Strategies

• Conservative bone resection: Avoid over-resection at PIPJ
• Arthrodesis over arthroplasty: More stable correction for rigid deformities
• Address MTPJ: Weil osteotomy if subluxed
• K-wire care: Clean pin sites, adequate duration (3-4 weeks)
• Patient selection: Avoid surgery in poorly controlled diabetics

Immediate Postoperative Period (0-2 Weeks)

Day 0-1:

• Dressing: Bulky postoperative dressing maintaining toe alignment
• K-wire care: If used, wire exits dorsally - keep dry and protected
• Elevation: Essential - foot above heart level to minimize swelling
• Weight-bearing: Heel weight-bearing in stiff-soled postoperative shoe

Week 1-2:

• First follow-up: Wound check at 10-14 days
• Suture removal: Non-absorbable sutures at 2 weeks
• Swelling management: Expect significant toe swelling for 6-8 weeks
• Activity: Limited ambulation for essential activities only

Early Recovery Phase (2-6 Weeks)

Week 2-4:

• K-wire removal: If used, remove at 3-4 weeks in clinic
• Active ROM: Begin gentle active toe movements after wire removal
• Footwear: Continue stiff-soled shoe; transition to accommodative shoe with stiff sole
• Buddy taping: Tape corrected toe to adjacent toe for 4-6 weeks post-wire removal

Week 4-6:

• Progressive weight-bearing: Transition to supportive athletic shoe
• Physical therapy: If stiffness present - focus on PIPJ mobility
• Wound massage: Scar mobilization after complete healing

Late Recovery Phase (6-12 Weeks)

• Footwear transition: Gradual return to regular shoes (wide toe box initially)
• Swelling: Toe swelling may persist 3-6 months - normal finding
• Return to activities: Low-impact exercise at 6-8 weeks, sports at 10-12 weeks
• Final assessment: Evaluate alignment and ROM at 12 weeks

Complications and Management

Expected Outcomes

Conservative:

• Symptom relief in 50-70%
• Deformity NOT corrected
• Typically progress over time
• Average 2-3 years before surgery

Surgical:

• Overall Satisfaction: 80-90%
• Pain Relief: 85-95%
• Deformity Correction: 75-90%
• Recurrence: 5-10%
• Complications: 10-20%

Factors Affecting Outcome

• Positive: Flexible deformity, isolated PIPJ, no MTPJ involvement
• Negative: Rigid deformity, MTPJ subluxation, inflammatory arthritis, diabetic

Return to Activity

• Walking: 2-4 weeks post-op
• Driving: 4-6 weeks
• Dress Shoes: 6-8 weeks
• Sports: 8-12 weeks
• Final Result: 6-12 months

• Arthroplasty vs arthrodesis for rigid deformity — Arthrodesis offers a more stable, lower-recurrence construct but at the cost of a stiff toe and a non-union risk; resection arthroplasty preserves some motion but is more prone to recurrence and floating toe. No high-quality RCT directly settles the choice, so selection remains driven by patient age, activity and surgeon preference.
• Intramedullary implants vs K-wire — The single RCT favours implants for fusion rate and patient-reported scores, yet pooled reviews show higher hardware-failure rates and a 640-894x cost premium with no clear complication benefit. Whether the avoided pin-tract morbidity justifies the cost is unresolved.
• When to address the MTPJ / plantar plate — There is debate over whether all crossover and instability-driven deformities need formal plantar plate repair, or whether a Weil osteotomy with soft-tissue balancing alone suffices. The Coughlin-Nery staging is increasingly used to guide this, but thresholds vary.
• Floating toe is partly unavoidable — Even with meticulous technique, floating toe occurs in a meaningful proportion after Weil osteotomy and plantar plate work; its true preventability and the best salvage remain uncertain.
• Role of percutaneous (minimally invasive) techniques — Percutaneous flexor tenotomy and minimally invasive osteotomies are expanding, but long-term comparative data against open correction are still limited.

Global Epidemiology

Lesser-toe deformities are among the most common forefoot complaints worldwide. Population studies report hammer/claw/mallet toes in a substantial minority of adults, rising steeply with age and strongly female-predominant (footwear and a longer second ray are the dominant drivers). Prevalence is higher in older, shod populations and lower in habitually barefoot communities, supporting footwear as a key modifiable factor. Hallux valgus coexists in the majority of symptomatic second-toe deformities.

Side-by-Side Guidance

There is no single international registry for lesser-toe surgery; comparative evidence comes from case series, the Jay/Malay fixation RCT, and large pooled fixation reviews rather than from arthroplasty-style joint registries.

High- vs Limited-Resource Practice Variation

• High-resource settings: Day-case surgery; growing use of intramedullary fusion implants despite cost and hardware-failure data favouring K-wires; frequent combined bunion + lesser-toe correction.
• Limited-resource settings: Percutaneous K-wire fixation and FDL tenotomy/transfer predominate (low cost, reliable); emphasis on footwear modification and offloading where surgical access is limited.
• Diabetic / neuropathic populations: Worldwide, the threshold for elective bony surgery is raised because of impaired healing; offloading, accommodative footwear and ulcer prevention take priority.