Bunion – Causes, Symptoms, Diagnosis, Treatment and Ongoing care
- Commonly known as a bunion, a hallux valgus deformity consists of a lateral deviation of the great toe (hallux) with medial deviation of the first metatarsal. There is often lateral rotation of the toe such that the nail faces medially (eversion) (1).
- Pressure at the head of the first metatarsal forces it to move medially. The hallux is forced laterally and a misalignment between the first metatarsal and the hallux develops. This results in a medial prominence of the first metatarsophalangeal (MTP) joint and a potentially painful and/or debilitating deformity.
- Strain on the medial collateral ligament along the MTP joint leads to loss of tensile strength, and eventually rupture, which decreases the medial stabilization of the joint (2).
- Changes in muscle positioning and tightening of the lateral collateral ligament can allow for the adductor hallucis muscle to pull unopposed, which can lead to hallux rotation (1).
- System(s) affected: Musculoskeletal/Skin
- Predominant age: More common in adults
- Predominant sex: Female > Male
- Prevalence increases with age.
- Familial predisposition
- Abnormal anatomy/mechanics
- Joint hypermobility or laxity
- Pronation of hindfoot
- Achilles tendon contracture
- Pes planus (fallen arches)
- Metatarsus primus varus
- Amputation of 2nd toe
- Inflammatory joint disease
- Neuromuscular disorders
- Exacerbated by improper footwear, especially tight-fitting or pointed shoes (3)
No known effective prevention exists, given that the etiology is poorly understood.
The exact etiology of hallux valgus is unknown, but the disease is thought to be multifactorial. The risk factors listed above may all contribute to the development of the disease.
Commonly Associated Conditions
- Medial bursitis of the 1st MTP joint (most common)
- Hammertoe deformity of the second phalanx
- Plantar callus
- Central metatarsalgia
- Metatarsalgia of MTP joint
- Degeneration of 1st metatarsal head cartilage
- Pronated feet
- Ankle equinus
- Ingrown toenail
- Entrapment of the medial dorsal cutaneous nerve
- Synovitis of the MTP joint (1,3)
- Most often made on clinical exam
- Radiography for staging purposes
- Pain or deformity at the 1st digit (great toe)
- Increased valgus angle at the 1st MTP joint
- Medial eminence of 1st metatarsal
- Bursal inflammation/ulceration over medial surface
- Painful callus development on 2nd toe
- Displacement of the 1st digit above/below 2nd digit
- Lateral deviation of other digits
- Impaired gait
- To perform a complete exam, the physician should:
- Observe the patient in sitting and standing positions, as weight bearing often accentuates the deformity.
- Assess the magnitude of hallux valgus deformity, including any rotation of the 1st digit.
- Measure the active/passive range of motion of the 1st MTP joint.
- Assess the congruency of the 1st MTP joint by passive correction of the deformity.
- Assess for pain and/or crepitus with movement of 1st MTP joint (may indicate degenerative osteoarthritis and change management).
- Assess the neurovasculature of the foot.
- Assess the gait of the patient (3)[C].
Diagnostic Tests & Interpretation
Weight-bearing anteroposterior, lateral, and oblique radiographs may be obtained. The radiographs are used to make the following measurements:
- Hallux abductus (HA) angle: Created by the bisection of the longitudinal axis of the hallux and the longitudinal axis of the first metatarsal.
- A normal angle is <20° (1).
- Deformity is considered severe when HA angle is >40° (2).
- Intermetatarsal (IM) angle: Created by the bisection of the longitudinal axes of the first and second metatarsals.
- A normal angle is <9° (1).
- Deformity is considered severe when IM angle is >16° (2).
- Medial prominence of the 1st metatarsal head: Note erosions or squaring.
- MTP joint congruency: A congruent joint displays no lateral subluxation of the proximal phalanx on the metatarsal head.
- Turf toe
- Stress fracture
- Septic arthritis
- Joint disorder:
- Rheumatoid arthritis
- Tendon disorder:
- Tendon rupture
- Foreign-body granuloma
Hallux valgus deformity will not resolve without treatment. Surgical treatment is more effective in improving patient outcomes than conservative therapy, although evidence is limited (4)[A].
While no medication is available to treat the underlying cause of hallux valgus, nonsteroidal anti-inflammatory agents can be used for relief of pain and swelling (5)[C]. As with the use of any medication, patients should be evaluated for contraindications and monitored for adverse reactions.
Conservative treatments (e.g., orthoses and night splints) did not appear to be any more beneficial in improving outcomes and preventing progression than no treatment (4). Evidence suggests that custom-made orthoses are a safe intervention that may slightly decrease pain at 6 and 12 months (but no continued decrease in pain after 12 months) compared to no treatment; however, this improvement is less than that seen with surgical interventions (see below) (6).
Despite the lack of strong evidence supporting the clinical efficacy of conservative therapy, a number of nonoperative modalities have been recommended to attempt to alleviate symptoms and decrease the rates of progression of hallux valgus deformity before surgical referral (5)[C]:
- Shoe modification: Low-heeled, wide shoes to alleviate pressure on MTP joint
- Orthoses: Shoe inserts may alter abnormal foot rotation
- Night splinting: May help balance supporting ligaments
- Stretching to improve intrinsic foot muscle strength
- Bunion pads: To decrease friction on the MTP joint
- Ice: To reduce inflammation
Complementary and Alternative Medicine
Marigold ointment may reduce pain and soft tissue swelling over an 8-week period (7)[C].
Surgery is indicated if patient has severe pain, dysfunction, or symptoms that do not improve with conservative therapy. Surgery is shown to be more beneficial than conservative therapy, and patient should be referred to a podiatric foot and ankle surgeon (5)[A]. More than 150 different surgical techniques have been performed, but evidence is too limited to show which form of surgery is more effective (4)[A]. It is important that patients have realistic expectations about surgical outcomes. Patients may not be able to fit into smaller shoes after surgery, and the great toe may not appear straight. Choice of surgical technique will depend on severity of disease. Examples include:
- Arthrodesis: Fusion of the 1st MTP joint
- Arthroplasty: Removing the joint or replacing it with a prosthesis
- Exostectomy/bunionectomy: Removing the medial bony prominence of the MTP joint
- Lapidus procedure: Fusion at the 1st metatarsocuneiform joint
- Soft-tissue procedure: To alter the function of surrounding ligaments and tendons
- Osteotomy and realignment
- Keller’s arthroplasty: Removal of the medial eminence on the metatarsal head and removal of part of the proximal phalanx, leaving a flexible joint
Activity after surgery is indicated to decrease joint stiffness. Post-operative treatment may include physical therapy, physiotherapy, use of supportive shoe, continuous passive motion or manual manipulation. Although there is little evidence to support clinical efficacy, physical therapy and gait training after surgery may improve ability to weight bear and ambulate after surgery (8) and passive motion may improve time to recovery and range of motion of MTP (4). Early weight bearing has not been found to be detrimental to final outcome (4). Refer to specific recommendation made by patient’s surgeon.
Patient outcome varies depending on individual factors, severity, and treatment modality used. The radiological HA angle is a predictor of surgical correction; patients with a HA angle <37° have a higher chance of having the deformity corrected with surgery compared to patients with a HA angle >37° (9).
All surgery carries the risk of wound infection or poor wound healing. Additional complications may include:
- Early swelling
- Hallux varus
- Recurrence of bunion
- Decreased sensation over the 1st metatarsal or phalanx (5)
1. Ferrari J, et al. Hallux valgus deformity (bunion). Article from UpToDate. Lasted updated 2/22/2010.
2. Glasoe WM, Nuckley DJ, Ludewig PM et al. Hallux valgus and the first metatarsal arch segment: a theoretical biomechanical perspective. Phys Ther. 2010;90:110–20.
3. Coughlin MJ. Hallux valgus. J Bone Joint Surg Am. 1996;78:932–66.
4. Ferrari J, et al. Interventions for treating hallux valgus (abductovalgus) and bunions. Cochrane Database of Systematic Reviews. 1, 2009.
5. Vanore JV, Christensen JC, Kravitz SR et al. Diagnosis and treatment of first metatarsophalangeal joint disorders. Section 1: Hallux valgus. J Foot Ankle Surg. 2003;42:112–23.
6. Hawke F, et al. Custom-made foot orthoses for the treatment of foot pain. Cochrane Database of Systematic Reviews. 1, 2009.
7. Khan MT. The podiatric treatment of hallux abducto valgus and its associated condition, bunion, with Tagetes patula. J Pharm Pharmacol. 1996;48:768–70.
8. Schuh R, Hofstaetter SG, Adams SB et al. Rehabilitation after hallux valgus surgery: importance of physical therapy to restore weight bearing of the first ray during the stance phase. Phys Ther.2009;89:934–45.
9. Deenik AR, de Visser E, Louwerens JW et al. Hallux valgus angle as main predictor for correction of hallux valgus. BMC Musculoskelet Disord. 2008;9:70.
Ashman CJ, Klecker RJ, Yu JS. Forefoot pain involving the metatarsal region: differential diagnosis with MR imaging. Radiographics. 2001;21:1425–40.
11. Klosok JK, Pring DJ, Jessop JH, et al. Chevron or Wilson metatarsal osteotomy for hallux valgus. A prospective randomised trial. J Bone Joint Surg Br. 1993;75:825–9.
415692008 Swelling of first metatarsophalangeal joint of hallux (disorder)
- When bunions occur in children or adolescents, the condition may be termed juvenile or adolescent hallux valgus, respectively, and is thought to have an etiology different from that in the adult population.
- Also known as a bunionette, a tailor’s bunion is a lateral prominence of the 5th metatarsal head.
- Patients should avoid any footwear with high heels, pointed toe boxes, or inadequate space for the toes to reduce the risk of bunions. Women’s high-heeled shoes and cowboy boots often fall into this category.