II. Epidemiology
- Most common in women (26% of women ages 18 to 65 years, 36% over age 65 years)
III. Definition
- Lateral Deviation of the Great Toe (first ray)
- Deviates at first Metatarsal-phalangeal joint (MTP)
IV. Risk Factors
- Strong familial predisposition
- Hypermobility of first Metatarsal
- Predisposing rheumatic conditions
- Environmental risks
- Wearing pointed, restrictive shoes (narrow toe box)
- Friction over medial first Metatarsal head
- Predisposing functional disorders
- Metatarsal primus varus
- Foot pronation
- Tight heel cord
- External Tibial Torsion
V. Associated Conditions
- Hammer toe deformity of second toe
- Osteoarthritis of the great toe MTP joint
VI. Symptoms
- Pain or deformity at great toe
VII. Signs
- Increased valgus angle at first MTP joint
- Valgus angle at first MTP joint usually <15 degrees
- Valgus angle in severe cases >30 degrees
- Bunion and inflamed overlying bursa
- Bony and soft tissue enlargement
- Occurs over medial Metatarsal head of great toe
- Soft tissue over Bunion may be inflamed and tender
- Painful callus development on 2nd toe
- Forced into hyperextension by deviated great toe
VIII. Radiology: Foot XRay
- Medial exostosis (Bunion)
- Hallux Valgus
- Lateral displacement proximal phalanx
- Degenerative changes
- First Metatarsal-phalangeal joint (great toe MTP)
IX. Management: Conservative Management
- Relieve pressure over painful Bunion prominence
- Correct functional factors
- Correct excessive pronation
- Correct Achilles tendon tightness
- Properly fitted, low heeled stiff-soled shoes
- Wide, square shaped toe box
- Toe portion stretched to accommodate Bunion (from custom shoemakers who stretch the material)
- Extra-depth shoe accommodates dorsiflexed second toe
- No inseam where shoe contacts medial Metatarsal head
- Functional foot Orthosis worn 5-6 hours on most days
- Splint separates first and second toe (may be effective, but no evidence to support)
- Avoid tight hose
-
Acute Pain Management
- Rest
- Apply moist heat
X. Management: Surgery
- Numerous surgical approaches are described elsewhere
- See resources below
- Surgery should correct biomechanical factors
- Simple Bunionectomy alone may not be effective
- Indications
- Severe deformity or Bunion pain
- Refractory to conservative management above
- Efficacy
- Reduced pain and improved function at 12 months, but no benefit at 2 years
- Torkki (2003) Acta Orthop Scand 74(2): 209-15 [PubMed]
XI. Complications
- Bunion ulceration and drainage
- Significant pain limiting activity
- Osteoarthritis of the first MTP joint
XII. Resources
- Textbook of Hallux Valgus and Forefoot Surgery
XIII. References
- Richardson in Canale (1998) Campbell's Ortho, p. 1621-4
- Martin in Ruddy (2001) Kelley's Rheumatology, p. 551
- Frykberg in Noble (2001) Primary Care Medicine, p. 1211
- Becker (2018) Am Fam Physician 98(5): 298-303 [PubMed]
- Torkki (2001) JAMA 285:2474-80 [PubMed]