Hammer Toes
PIPJ Flexion Deformity
Lesser Toe Deformity Types
Critical Must-Knows
- Hammer Toe: PIPJ flexion with neutral DIPJ and MTPJ - most common lesser toe deformity.
- Claw Toe: MTPJ hyperextension with PIPJ AND DIPJ flexion - often neurological cause.
- Mallet Toe: Isolated DIPJ flexion only - least common, affects terminal tendon.
- Flexible vs Rigid: Correctable with ankle plantarflexed (FDL relaxed) = flexible.
- Flexibility Test: Critical - determines soft tissue vs bone surgery.
Examiner's Pearls
- "Plantarflex ankle to test flexibility (relaxes FDL)
- "Always assess MTPJ stability - Drawer test
- "Flexible = FDL tenotomy/transfer
- "Rigid = PIPJ arthroplasty or arthrodesis
- "Address MTPJ if subluxed (Weil osteotomy)
Flexibility is the Key Exam Finding
The flexibility test determines your entire surgical approach.
- Flexible: Correct PIPJ with ankle PLANTARFLEXED (this relaxes FDL).
- If it corrects = Flexible → Soft tissue surgery (FDL tenotomy or transfer).
- If fixed = Rigid → Bone surgery (PIPJ arthroplasty or arthrodesis).
- Always check MTPJ - subluxation needs Weil osteotomy.
- Drawer test - anterior draw of proximal phalanx indicates MTPJ instability.
Hammer vs Claw vs Mallet Deformity
| Feature | Hammer Toe | Claw Toe | Mallet Toe |
|---|---|---|---|
| Neutral/Extended | HYPEREXTENDED | Neutral | |
| FLEXED | FLEXED | Neutral | |
| Neutral | FLEXED | FLEXED | |
| 80% of lesser toe | 15% of lesser toe | 5% of lesser toe | |
| Shoe wear, hallux valgus | Neurological (CMT, DM) | Trauma, long 2nd toe | |
| FDL/FDB overpull | Intrinsic weakness | FDP/terminal tendon |
Flexible Hammer
Rigid Hammer
MTPJ Subluxation
Crossover Toe
At a Glance
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.
Deformity Types - HCM
Memory Hook:HCM - Hammer at PIP, Claw everywhere (neurological), Mallet at DIP (terminal)
Flexibility Test - PLANT
Memory Hook:PLANT the ankle down to test flexibility - if it corrects with FDL lax, it's flexible.
Surgical Options - FRA
Memory Hook:FRA - Flexible gets FDL surgery, Rigid needs Arthroplasty/Arthrodesis.
Complications - FIRS
Memory Hook:FIRS - Floating toe is the most common complaint post hammer toe surgery.
Overview and Epidemiology
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
Pathophysiology and Anatomy
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
Clinical Assessment
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
-
Standing Assessment
- Observe toe position weight-bearing
- Check for associated hallux valgus
- Assess arch, hindfoot alignment
-
Seated Examination
- Flexibility Test: Most critical exam finding
- Plantarflex ankle (relaxes FDL)
- Attempt to correct PIPJ deformity
- If corrects = Flexible
- If fixed = Rigid
- Flexibility Test: Most critical exam finding
-
MTPJ Assessment
- Drawer Test: Grasp toe, attempt to sublux proximally
- Positive = MTPJ instability (plantar plate injury)
- Assess MTPJ ROM
-
Callus/Skin
- Dorsal PIPJ: From shoe pressure
- Tip of toe: From ground contact
- Interdigital: From adjacent toe pressure
-
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
Investigations
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)
Exam Pearl
Weight-bearing X-rays are essential - non-weight-bearing images miss MTPJ subluxation and underestimate deformity severity.
Management Algorithm
Floating Toe - Most Common Complaint
Floating toe is the most common post-operative complaint. The toe has no ground purchase and feels floppy. Prevention: avoid over-resection, use arthrodesis for stability, address MTPJ subluxation. Salvage is difficult.
Complications and Outcomes
Surgical Complications
Hammer Toe Surgery Complications
| Complication | Incidence | Risk Factors | Prevention/Management |
|---|---|---|---|
| Floating toe | 5-10% | Over-resection, tendon imbalance, MTPJ instability | Limit resection, arthrodesis, address MTPJ |
| Recurrence | 5-15% | Inadequate correction, not addressing MTPJ | Complete correction, treat all pathology |
| K-wire infection | 3-8% | Pin track contamination, diabetes | Pin care, early removal if infected |
| Stiffness | 5-10% | Excessive scarring, prolonged immobilization | Early mobilization, physiotherapy |
| Malalignment | 2-5% | Technical error, inadequate fixation | Careful intraoperative assessment |
| Transfer metatarsalgia | 5-10% | Shortening adjacent ray, overcorrection | Address all metatarsals, balanced correction |
Floating Toe - Most Common Complication
The toe has no ground purchase and feels floppy. Causes include over-resection at PIPJ, tendon imbalance, and unaddressed MTPJ subluxation. Prevention through conservative bone resection, arthrodesis for stability, and addressing MTPJ pathology is key. Salvage is difficult.
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
Postoperative Care
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
Exam Pearl
Postoperative Swelling Timeline: Inform patients that toe swelling following hammer toe correction typically peaks at 2-3 weeks and may persist for 3-6 months. Prolonged swelling does not indicate failure if alignment is maintained.
Complications and Management
| Complication | Incidence | Prevention/Management |
|---|---|---|
| Recurrence | 5-15% | Proper patient selection; address MTPJ if subluxed |
| Floating toe | 2-5% | Avoid excessive plantar plate release |
| Mallet toe | 3-8% | Check DIPJ mobility preoperatively |
| Stiffness | 10-20% | Early ROM after fixation; consider arthroplasty in elderly |
| Infection | 1-3% | Standard wound care; K-wire pin site care |
| Transfer metatarsalgia | 5-10% | Address 1st ray pathology; consider Weil osteotomy |
Outcomes and Prognosis
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
Evidence Base
- Hammer toe surgery outcomes in 118 patients
- 89% patient satisfaction
- PIPJ arthrodesis more stable than arthroplasty
- Recurrence 5% with arthrodesis vs 15% with arthroplasty
- Weil osteotomy for MTPJ disorders
- 142 metatarsals in 89 patients
- 85% satisfaction
- Floating toe 5%, transfer metatarsalgia 8%
- Girdlestone-Taylor procedure outcomes
- 82% good/excellent results
- More effective when combined with MTPJ release
- 10% recurrence rate
- Comparison of K-wire vs intramedullary implant for PIPJ fusion
- Similar fusion rates (92% vs 94%)
- Less infection with buried implant
- No implant removal needed
- Insufficient evidence to recommend one procedure over another
- Need for randomized controlled trials
- Most evidence is Level IV case series
- Flexible vs rigid distinction is critical
Viva Scenarios
Practice these scenarios to excel in your viva examination
Flexible Hammer Toe
"A 55-year-old woman presents with a painful 2nd toe deformity. She has a callus over the dorsal aspect of the PIPJ. On examination, the deformity corrects manually when you plantarflex her ankle."
Diagnosis: This is a flexible hammer toe of the 2nd toe. The key finding is that the deformity corrects manually with the ankle plantarflexed, which relaxes the FDL and confirms flexibility.
Clinical Assessment:
- Confirm flexibility by plantarflexing ankle
- Assess MTPJ with Drawer test for instability
- Check for associated hallux valgus
- Examine other toes
- Weight-bearing X-rays
Management:
- Conservative first: Shoe modifications (wide toe box, soft upper), padding, toe sleeves
- If fails conservative: Surgical intervention
- Flexible deformity = soft tissue surgery:
- FDL tenotomy (percutaneous) - simple, effective for isolated PIPJ
- Girdlestone-Taylor transfer - better if MTPJ instability
Key Principle: Flexible deformity does NOT require bone resection. Soft tissue balancing is sufficient. Over-treatment with bone resection risks floating toe.
Rigid Hammer Toe with MTPJ Involvement
"A 62-year-old man has a painful, rigid 2nd toe deformity. The PIPJ does not correct even with the ankle plantarflexed. You also notice the toe is dorsally displaced at the MTPJ level with a positive Drawer test."
Diagnosis: This is a rigid hammer toe with MTPJ subluxation (Grade 3 or 4 by Dhukaram classification). The combination requires addressing both levels.
Clinical Assessment:
- Confirm rigidity - does not correct with ankle plantarflexed
- Positive Drawer test confirms MTPJ instability
- Assess degree of MTPJ subluxation/dislocation
- Check for associated hallux valgus
- Weight-bearing X-rays - assess joint destruction
Surgical Management:
- PIPJ level: PIPJ resection arthroplasty or arthrodesis
- Arthrodesis preferred for stability and lower recurrence
- MTPJ level: Weil osteotomy to shorten metatarsal
- Combined with plantar plate repair if torn
- May need extensor tenotomy and MTPJ capsulotomy
- Fixation: K-wire through toe or intramedullary device
Complications to Discuss:
- Floating toe (most common complaint)
- Recurrence if MTPJ not addressed
- Stiffness post-arthrodesis
- Transfer metatarsalgia
Floating Toe Post-Surgery
"A patient returns 3 months after hammer toe surgery complaining their 2nd toe feels floppy and doesn't touch the ground when standing. They are unhappy with the result."
Diagnosis: This is a floating toe - the most common complication and complaint after hammer toe surgery. The toe lacks ground purchase and feels unstable.
Causes of Floating Toe:
- Over-resection of proximal phalanx head
- Excessive soft tissue release
- Tendon imbalance (weak flexors)
- MTPJ instability not addressed
- Malunion/non-union of fusion
Assessment:
- Examine toe position and ground contact
- Check flexor strength (FDL intact?)
- Assess MTPJ stability
- X-ray to assess bone resection, alignment, fusion
Management Options:
- Conservative: Strapping, buddy taping, time
- Surgical salvage (difficult):
- Flexor tendon transfer if intact
- MTPJ stabilisation procedure
- Bone grafting if over-resected
- Syndactylization to adjacent toe (last resort)
- Prognosis: Salvage surgery unpredictable, manage expectations
Prevention:
- Avoid over-resection
- Use arthrodesis for stability
- Address MTPJ subluxation at index surgery
- Adequate K-wire duration
MCQ Practice Points
Classic MCQ: Lesser Toe Deformity Definitions
Q: What distinguishes a hammer toe from a claw toe?
A: Hammer toe = PIPJ flexion with neutral MTPJ and DIPJ Claw toe = MTPJ hyperextension + PIPJ/DIPJ flexion
Hammer toe is most commonly 2nd toe, associated with hallux valgus. Claw toe typically affects multiple toes and has neurological associations (Charcot-Marie-Tooth, diabetic neuropathy).
Key Surgical Decision: Flexibility Assessment
Q: A 55-year-old woman has a painful 2nd hammer toe. The PIPJ deformity corrects passively. What is the first-line surgical treatment?
A: Flexor-to-extensor transfer (Girdlestone-Taylor procedure) - indicated for flexible deformities. Preserves joint motion.
If the PIPJ is fixed/rigid → PIPJ arthrodesis is indicated.
Critical Anatomy: Push-up Test
Q: What does the push-up test assess in hammer toe evaluation?
A: Tests MTPJ stability. With examiner pressure under the metatarsal head, a positive test shows correction of PIPJ deformity → indicates the problem is plantar plate/MTPJ driven, not isolated PIPJ contracture. May need Weil osteotomy in addition to toe surgery.
Complication Recognition
Q: Following hammer toe correction, a patient develops progressive DIPJ hyperextension ("floppy toe"). What is the cause?
A: FDL transection or excessive release during surgery. The FDL is the only active DIPJ flexor. If cut or transferred, unopposed EDL causes DIPJ hyperextension. Prevention: careful identification of FDL vs FDB.
Australian Context
Australian Epidemiology and Practice
Hammer toe is common in Australia, particularly among women in the 40-60 age group. The condition is closely associated with footwear choices and frequently coexists with hallux valgus. Most surgical correction is performed as day surgery in both public and private hospital settings.
Australian Practice Patterns
- Most hammer toe surgery performed by orthopaedic foot/ankle surgeons or podiatric surgeons
- Day surgery model predominant
- Increasing use of intramedullary fixation devices
- Combined procedures common (bunion + hammer toe)
Indigenous Considerations
- Lower rates of hammer toe surgery in Indigenous populations
- Higher rates of diabetic foot complications
- Access to specialist care variable in rural/remote areas
Relevant Guidelines
- AOFAS: American Orthopaedic Foot and Ankle Society guidelines widely adopted
- No specific Australian guidelines for hammer toe
- Diabetic Foot Guidelines: NHMRC guidelines for diabetic foot assessment important in this population
HAMMER TOES
High-Yield Exam Summary
DEFINITION & TYPES
- •Hammer = PIPJ flexion, neutral MTPJ/DIPJ (80% of lesser toe)
- •Claw = MTPJ extension + PIPJ/DIPJ flexion (neurological)
- •Mallet = DIPJ flexion only (5%, terminal tendon)
- •2nd toe most common (80%) - length, hallux valgus
FLEXIBILITY TEST
- •Plantarflex ankle (relaxes FDL)
- •Attempt to correct PIPJ
- •Corrects = FLEXIBLE → soft tissue surgery
- •Fixed = RIGID → bone surgery
MTPJ ASSESSMENT
- •Drawer test - anterior subluxation
- •Positive = plantar plate rupture/MTPJ instability
- •Must address if subluxed (Weil osteotomy)
- •Missing MTPJ = recurrence
FLEXIBLE SURGERY
- •FDL tenotomy (percutaneous stab incision)
- •Girdlestone-Taylor (FDL split and transfer dorsally)
- •May need MTPJ capsulotomy
- •No bone resection needed
RIGID SURGERY
- •PIPJ resection arthroplasty (resect P1 head)
- •PIPJ arthrodesis (more stable, lower recurrence)
- •K-wire 3-4 weeks or intramedullary device
- •Weil osteotomy if MTPJ subluxed
COMPLICATIONS
- •Floating toe - MOST COMMON (floppy, no purchase)
- •Recurrence (5-10%)
- •K-wire infection (3-8%)
- •Stiffness, mallet toe, transfer lesions
OUTCOMES
- •80-90% satisfaction
- •Arthrodesis lower recurrence than arthroplasty
- •Conservative doesn't correct deformity
- •Full recovery 6-12 months