Bunions
Exam Tips
- In OSCEs, diagnose bunion clinically first; do not state routine primary-care X-ray is mandatory.
- Always examine standing and seated, and inspect gait, shoe wear pattern, skin integrity, and neurovascular status.
- Quote key radiographic thresholds when asked about severity: hallux valgus angle >15 degrees, intermetatarsal angle >9 degrees on weight-bearing films.
- Mention red flags for urgent referral: non-healing ulcer, suspected ischaemia, or diabetic foot risk.
- For management stations, prioritise footwear modification and podiatry before surgery, and state surgery is not for cosmetic indication alone.
- Differentiate from hallux rigidus: valgus deformity with medial eminence vs painful stiff arthritic first MTP with reduced dorsiflexion.
Definition
A bunion (hallux valgus) is a progressive deformity of the first ray in which the great toe deviates laterally toward the lesser toes and the first metatarsal head becomes medially prominent. It is not only a cosmetic issue: the deformity alters forefoot biomechanics, can inflame overlying bursal soft tissue, and commonly causes pain with walking and shoe wear.
Pathophysiology
Hallux valgus develops through multifactorial biomechanical failure at the first metatarsophalangeal (MTP) joint. Progressive medial drift of the first metatarsal with lateral deviation and pronation of the hallux leads to capsuloligamentous imbalance (relative dominance of adductor hallucis over abductor hallucis), sesamoid maltracking, and joint incongruity. This redistributes plantar load to the lesser metatarsal heads, causing metatarsalgia/callus formation and, over time, may contribute to first MTP osteoarthritic change (hallux rigidus). See Figure: weight-bearing AP foot radiograph demonstrating hallux valgus angle >15 degrees and intermetatarsal angle >9 degrees.
Risk Factors
- Constricting footwear (tight toe box, high heels)
- Increasing age
- Female sex
- Family history/genetic predisposition
- Pes planus and excessive pronation
- Associated deformities (metatarsus adductus, hammer toe, equinus)
- Achilles tendon tightness/contracture
- Ligamentous laxity
- Long first metatarsal morphology
- Neuromuscular disease (for example cerebral palsy, post-stroke states)
Clinical Features
Symptoms
- Medial first MTP/forefoot pain, often progressive
- Pain worse with weight-bearing and narrow footwear
- Difficulty finding comfortable shoes
- Functional limitation in walking, standing, or activities
- Cosmetic concern may be present but does not alone justify specialist referral
Signs
- Lateral deviation of hallux at first MTP joint
- Medial prominence of first metatarsal head (bunion)
- Local tenderness over first MTP/medial eminence
- Bursal irritation, callus or corn at overload points (often under second MTP)
- Reduced first MTP range of motion or stiffness (suggesting coexistent OA)
- Associated deformities: pes planus, lesser toe deformity, second toe subluxation/hammer toe
- Abnormal gait or lower-limb alignment; inspect footwear wear pattern
- Neurovascular deficit or skin breakdown in high-risk patients (especially diabetes)
Investigations
Management
Lifestyle Modifications
- Use low-heeled, wide toe-box, soft-soled footwear; avoid tight or high-heeled shoes
- Consider toe spacers, bunion pads, and insoles/orthoses for pressure redistribution
- Ice packs for short-term pain/inflammation relief
- Podiatry referral for footwear optimisation and orthotic/night splint consideration
- MSK/physiotherapy input for balance, proprioception, calf stretching, and management of tibialis posterior dysfunction
- Urgent referral if non-healing/impending ulcer or suspected limb ischaemia; diabetic patients may need diabetic foot protection service referral
Pharmacological Treatment
Simple analgesic
- Paracetamol 1 g orally every 4-6 hours when required (maximum 4 g in 24 hours)
First-line for pain if no contraindication; reduce maximum dose in low body weight, frailty, or hepatic impairment/risk factors for hepatotoxicity.
NSAID (oral)
- Ibuprofen 200-400 mg orally three times daily with food (usual maximum 1.2 g/day OTC; up to 2.4 g/day in prescription settings)
- Naproxen 250-500 mg orally twice daily
Use lowest effective dose for shortest duration. Avoid/caution in chronic kidney disease, heart failure, peptic ulcer disease, anticoagulant use, uncontrolled hypertension, NSAID-exacerbated asthma, and pregnancy (especially third trimester). Consider gastroprotection (for example omeprazole 20 mg once daily) in higher GI-risk adults.
NSAID (topical)
- Topical diclofenac gel to painful area 3-4 times daily (follow product-specific maximum daily dose)
Lower systemic adverse-effect burden than oral NSAIDs; still caution with NSAID hypersensitivity and avoid on broken skin.
Injection therapy (specialist setting)
- Corticosteroid injection around symptomatic first MTP/bursal region (agent and dose per specialist protocol, e. g. methylprednisolone acetate with local anaesthetic)
Consider when surgery is unsuitable; avoid through infected skin and use caution in poorly controlled diabetes due to transient hyperglycaemia.
Surgical / Interventional
- Refer to foot and ankle orthopaedic or podiatric surgery if progressive deformity/symptoms, failure of >=3 months conservative treatment, second toe involvement, major functional impact, or inability to wear suitable footwear
- Distal/proximal first metatarsal osteotomy (for example chevron or scarf) often combined with soft-tissue balancing
- Akin proximal phalanx osteotomy as adjunct for residual hallux valgus
- First tarsometatarsal fusion (Lapidus procedure) in selected hypermobility/severe deformity patterns
- First MTP arthrodesis for severe deformity with arthritis or failed prior correction
- Do not refer for surgery solely for cosmetic reasons or prophylaxis without symptoms
Complications
- Chronic forefoot and great toe pain
- Footwear intolerance and reduced mobility
- Callus/corn formation due to transfer metatarsalgia
- First MTP osteoarthritis (hallux rigidus)
- Impaired balance and increased falls risk
- First MTP subluxation in severe deformity
- Second toe dorsal subluxation/dislocation or hammer toe
- Skin breakdown, ulceration, and potential osteomyelitis, especially with diabetes and neuropathy
Prognosis
Course is variable but often slowly progressive, particularly with larger baseline deformity angles. Some patients remain stable with conservative care, while others develop increasing deformity, pain, and functional limitation over years, prompting surgical consideration.
Sources & References
✅NICE Guidelines(1)
- Bunions[overview]