Bunions 
​Overview
A bunion, or hallux valgus, is a common forefoot deformity in which the first metatarsophalangeal (MTP) joint deviates laterally, creating a prominent bump on the inner side of the big toe.
This condition can cause pain, redness, swelling, shoe irritation, and difficulty with footwear or activity.
Bunions are progressive: untreated, the deformity and symptoms often worsen over time.


Etiology (Causes and Risk Factors)
Bunion formation is multifactorial, arising from a combination of genetic, structural, and environmental influences.
Intrinsic/Structural Factors
  • Genetic predisposition: Family history is strongly associated with hallux valgus development.
  • Foot type: Pes planus (flatfoot), ligamentous laxity, and metatarsus primus varus (increased first–second metatarsal angle) increase risk.
  • Abnormal first ray mechanics: Hypermobility of the first tarsometatarsal joint can contribute.
Extrinsic/Environmental Factors
  • Footwear: Chronic use of narrow, pointed, or high-heeled shoes that crowd the toes is a recognized aggravating factor.
  • Occupation/activities: Professions or sports requiring prolonged standing or narrow footwear can increase stress.
Associated Conditions
  • Inflammatory arthritis (e.g., rheumatoid arthritis)
  • Neuromuscular disorders
  • Previous trauma to the first MTP joint
Progressive lateral deviation of the hallux and medial deviation of the first metatarsal lead to joint subluxation, sesamoid malalignment, and eventual pain and degenerative changes.


Clinical Presentation and Diagnosis
Symptoms
  • Medial eminence pain and swelling over the first MTP joint.
  • Difficulty wearing shoes; discomfort with prolonged walking or standing.
  • Cosmetic concerns due to toe deviation.
Physical Exam
  • Inspection reveals lateral hallux deviation and medial eminence prominence.
  • Assess range of motion, first ray mobility, and presence of calluses or transfer lesions.
Imaging
  • Weight-bearing radiographs (AP, lateral, oblique) measure:
    • Hallux valgus angle (HVA)
    • Intermetatarsal angle (IMA)
    • Sesamoid position
  • Radiographs guide classification and surgical planning.


Treatment
Management depends on symptom severity, patient goals, and degree of deformity.
Nonoperative (Conservative)
  • Footwear modification: Wide toe-box shoes, low heels, soft uppers to reduce pressure.
  • Orthoses / pads / spacers: May alleviate discomfort and improve pressure distribution.
  • Anti-inflammatory medications or topical agents for pain control.
  • Activity modification to reduce painful weight-bearing.
Conservative measures can relieve symptoms but do not correct the deformity or prevent progression.
Operative
Surgery is indicated when pain and functional limitation persist despite appropriate nonoperative care.
Procedures are selected based on severity, joint congruity, and presence of arthritis:
  • Distal osteotomies (e.g., chevron, scarf) for mild to moderate deformities.
  • Proximal osteotomies or Lapidus procedure (first tarsometatarsal fusion) for moderate to severe deformities or first-ray hypermobility.
  • MTP arthrodesis for severe deformity or arthritic joints.
  • Minimally invasive bunion surgery (MIBS) has emerged as a contemporary option with reported benefits of less soft tissue disruption, smaller scars, and quicker early recovery in select patients.
All procedures aim to realign the first metatarsal, correct sesamoid position, and relieve pain.


Expectations and Prognosis
  • Nonoperative care: Can significantly reduce pain but does not reverse the deformity.
  • Postoperative course:
    • Protected weight-bearing or postoperative shoe for 4–8 weeks depending on procedure.
    • Gradual transition to regular footwear and full activity over 8–12 weeks for most osteotomies; fusion procedures may require longer.
  • Outcome: Modern surgical techniques achieve pain relief and deformity correction in the majority of patients, with long-term satisfaction rates often above 80–90%.
  • Risks: Recurrence of deformity, stiffness, hardware irritation, infection, transfer metatarsalgia, and nerve symptoms are recognized complications.
  • Prognostic factors: Better outcomes are associated with adequate correction of intermetatarsal angle, stable fixation, and adherence to postoperative protocols.


Key References (Peer-Reviewed)
  1. Coughlin MJ, Jones CP. Hallux valgus: demographics, etiology, and radiographic assessment. Foot Ankle Int. 2007;28(7):759–777.
  2. Nix S, Smith M, Vicenzino B. Prevalence of hallux valgus in the general population: a systematic review and meta-analysis. J Foot Ankle Res. 2010;3:21.
  3. Easley ME, Trnka HJ. Current concepts review: hallux valgus part II: operative treatment. Foot Ankle Int. 2007;28(6):748–758.
  4. Schneider W, Csepan R, Knahr K. Recurrent hallux valgus: causes and long-term results after operative correction. Foot Ankle Int. 2002;23(5):448–453.
  5. Brogan K, Lindisfarne E, Akehurst H, Farook U, Shrier W, Palmer S. Minimally invasive and open distal chevron osteotomy for mild to moderate hallux valgus: a randomized controlled trial. Bone Joint J. 2016;98-B(10):1376–1382.
  6. Dayton P, Feilmeier M, Kauwe M, McArdle A. Comparison of radiographic outcomes between minimally invasive and open modified Lapidus bunionectomy. J Foot Ankle Surg. 2019;58(3):427–431.


Summary
Bunions (hallux valgus) are progressive deformities caused by a combination of hereditary and mechanical factors. While well-fitted footwear and orthotics can reduce pain, only surgery corrects the underlying deformity. Modern procedures—including minimally invasive techniques—offer high rates of pain relief and functional improvement when tailored to deformity severity and patient needs.