Abunion,also known ashallux valgus,is a deformity of theMTP jointconnecting thebig toeto thefoot.[2]The big toe often bends towards the other toes and the joint becomes red and painful.[2]The onset of bunions is typically gradual.[2]Complications may includebursitisorarthritis.[2]
| Bunion | |
|---|---|
| Other names | Hallux abducto valgus, hallux valgus[1] |
 | |
| Specialty | Orthopedics,podiatry |
| Symptoms | Prominent, red, and painful joint at the base of the big toe[2] |
| Complications | Bursitis,arthritis[2] |
| Usual onset | Gradual[2] |
| Causes | Unclear[1] |
| Risk factors | Wearing overly tight shoes,high-heeled shoes,family history,rheumatoid arthritis[2][3] |
| Diagnostic method | Based on symptoms,X-rays[2] |
| Differential diagnosis | Osteoarthritis,Freiberg's disease,hallux rigidus,Morton's neuroma[4] |
| Treatment | Propershoes,orthotics,NSAIDs,surgery[2] |
| Frequency | ~23% of adults[1] |
The exact cause is unclear.[1]Proposed factors include wearing overly tightshoes,high-heeled shoes,family history, andrheumatoid arthritis.[2][3]Diagnosis is generally based on symptoms and supported byX-rays.[2]A similar condition of the little toe is referred to as abunionette.[2]
Treatment may include proper shoes,orthotics,orNSAIDs.[2]If this is not effective for improving symptoms, surgery may be performed.[2]It affects about 23% of adults.[1]Females are affected more often than males.[2]Usual age of onset is between 20 and 50 years old.[1]The condition also becomes more common with age.[1]It was first clearly described in 1870.[1]Archaeologistshave identified a high incidence of bunions in skeletons from14th- and 15th-century England,coinciding with a fashion for pointy shoes.[5][6]
Signs and symptoms
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Symptoms may include irritation of the skin around the bunion, and blisters may form more easily at the site. Pain may be worse when walking.
Bunions can lead to difficulties finding properly fitting footwear and may force a person to buy a larger size shoe to accommodate the width of the bunion. If the bunion deformity becomes severe enough, the foot can hurt in different places even without the constriction of shoes. It is then considered as being a mechanical function problem of the forefoot.
Cause
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The exact cause is unclear.[1]It may be due to a combination of internal and external causes.[7]Proposed factors include wearing overly tightshoes,high-heeled shoes,family history[2][3]andrheumatoid arthritis.The American College of Foot and Ankle Surgeons states that footwear only worsens a problem caused bygenetics.[8]
Excessivepronation of the footcauses increased pressure on the inside of the big toe that can result in adeformationof the medial capsular structures of the joint, subsequently increasing the risk of developing bunions.[7][9]
Pathophysiology
editThe bump itself is partly due to the swollenbursal sacor an osseous (bony) anomaly on the metatarsophalangeal joint. The larger part of the bump is a normal part of the head of the first metatarsal bone that has tilted sideways to stick out at its distal (far) end (metatarsus primus varus).
Bunions are commonly associated with a deviated position of the big toe toward the second toe, and the deviation in the angle between the first and second metatarsal bones of the foot. The smallsesamoidbones found beneath the first metatarsal (which help the flexor tendon bend the big toe downwards) may also become deviated over time as the first metatarsal bone drifts away from its normal position.Osteoarthritisof the first metatarsophalangeal joint, diminished or altered range of motion, and discomfort with pressure applied to the bump or with motion of the joint, may all accompany bunion development. Atop of the first metatarsal head either medially or dorso-medially, there can also arise a bursa that when inflamed (bursitis), can be the most painful aspect of the process.
Diagnosis
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Bunions can be diagnosed and analyzed with asimple x-ray,which should be taken with the weight on the foot.[10]Thehallux valgus angle(HVA) is the angle between the long axes of theproximal phalanxand the firstmetatarsal boneof the big toe. It is considered abnormal if greater than 15–18°.[11]The following HV angles can also be used to grade the severity of hallux valgus:[12][unreliable medical source?]
- Mild: 15–20°
- Moderate: 21–39°
- Severe: ≥ 40°
Theintermetatarsal angle(IMA) is the angle between the longitudinal axes of the first and second metatarsal bones, and is normally less than 9°.[11]The IM angle can also grade the severity of hallux valgus as:[12]
- Mild: 9–11°
- Moderate: 12–17°
- Severe: ≥ 18°
Treatment
editConservative treatment for bunions include changes in footwear, the use oforthotics(accommodative padding and shielding), rest, ice, andpain medicationssuch asacetaminophenornonsteroidal anti-inflammatory drugs.These treatments address symptoms but do not correct the actual deformity.[13]If the discomfort persists and is severe or when aesthetic correction of the deformity is desired, surgical correction by anorthopedic surgeonor apodiatricsurgeonmay be necessary.
Orthotics
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Orthotics aresplintsor regulators while conservative measures include various footwear like toe spacers,valgussplints, and bunion shields. Toe spacers seem to be effective in reducing pain, but there is no evidence that any of these techniques reduces the physical deformity. There are a variety of available orthotics including off-the-shelf commercial products and custom-molded orthotics, which may be prescribed medical devices.[14]
Surgery
editProcedures are designed and chosen to correct a variety of pathologies that may be associated with the bunion. For instance, procedures may address some combination of:
- removing the abnormal bony enlargement of the firstmetatarsal,
- realigning the first metatarsal bone relative to the adjacent metatarsal bone,
- straightening the great toe relative to the first metatarsal and adjacent toes,
- realigning the cartilaginous surfaces of the great toe joint,
- addressingarthriticchanges associated with the great toe joint,
- repositioning thesesamoid bonesbeneath the first metatarsal bone,
- shortening, lengthening, raising, or lowering the first metatarsal bone,
- correcting any abnormal bowing or misalignment within the great toe,
- connecting two parallel long bones side by side bysyndesmosis procedure
At present there are many different bunion surgeries for different effects. The age, health, lifestyle and activity level of the patient may also play a role in the choice of procedure.
Traditional bunion surgery can be performed under local, spinal or generalanesthetic.A person who has undergone bunion surgery can expect a 6- to 8-week recovery period during whichcrutchesare usually required to aid mobility. Anorthopedic castis much less common today as newer, more stable procedures and better forms of fixation (stabilizing the bone with screws and other hardware) are used. Hardware may even include absorbable pins that perform their function and are then broken down by the body over the course of months. After recovery long term stiffness or limited range of motion may occur in some patients. Visible or limited scarring may also occur for patients.
References
edit- ^abcdefghiDayton, Paul D. (2017).Evidence-Based Bunion Surgery: A Critical Examination of Current and Emerging Concepts and Techniques.Springer. pp.1–2.ISBN9783319603155.
- ^abcdefghijklmnopq"Bunions".OrthoInfo - AAOS.February 2016.Retrieved8 November2017.
- ^abcdBarnish, MS; Barnish, J (13 January 2016)."High-heeled shoes and musculoskeletal injuries: a narrative systematic review".BMJ Open.6(1): e010053.doi:10.1136/bmjopen-2015-010053.PMC4735171.PMID26769789.
- ^Ferri, Fred F. (2010).Ferri's Differential Diagnosis E-Book: A Practical Guide to the Differential Diagnosis of Symptoms, Signs, and Clinical Disorders.Elsevier Health Sciences. p. 323.ISBN978-0323081634.
- ^Dittmar, Jenna; Mitchell, Piers (11 June 2021)."Fashion for pointy shoes unleashed a wave of bunions in medieval England".The Conversation.Retrieved2021-06-28.
- ^Dittmar, Jenna M.; Mitchell, Piers D.; Cessford, Craig; Inskip, Sarah A.; Robb, John E. (2021-06-11)."Fancy shoes and painful feet: Hallux valgus and fracture risk in medieval Cambridge, England".International Journal of Paleopathology.35:90–100.doi:10.1016/j.ijpp.2021.04.012.ISSN1879-9817.PMC8631459.PMID34120868.
- ^abBrukner, Peter (2010).Clinical sports medicine(3 ed.). McGraw-Hill. p. 667.ISBN9780070278998.
- ^"Bunions (Hallux Abducto Valgus)".Footphysicians.com. 2009-12-18. Archived fromthe originalon 2011-12-08.Retrieved2011-03-20.
- ^Chou, Loretta B. (19 June 2015). "Disorders of the First Metatarsophalangeal Joint".The Physician and Sportsmedicine.28(7):32–45.doi:10.3810/psm.2000.07.1075.PMID20086649.S2CID21529142.
- ^Page 533in:Sam W. Wiesel, John N. Delahay (2007).Essentials of Orthopedic Surgery(3 ed.). Springer Science & Business Media.ISBN9780387383286.
- ^abRebecca Cerrato, Nicholas Cheney."Hallux Valgus".American Orthopaedic Foot & Ankle Society.Archived fromthe originalon 2016-12-30.Retrieved2016-12-30.Last reviewed June 2015
- ^abPiqué-Vidal, Carlos; Vila, Joan (2009)."A geometric analysis of hallux valgus: correlation with clinical assessment of severity".Journal of Foot and Ankle Research.2(1): 15.doi:10.1186/1757-1146-2-15.ISSN1757-1146.PMC2694774.PMID19442286.
- ^Hecht, PJ; Lin, TJ (March 2014). "Hallux valgus".Medical Clinics of North America(Review).98(2):227–32.doi:10.1016/j.mcna.2013.10.007.PMID24559871.
- ^Park, CH; Chang, MC (May 2019)."Forefoot disorders and conservative treatment".Yeungnam University Journal of Medicine.36(2):92–98.doi:10.12701/yujm.2019.00185.PMC6784640.PMID31620619.(see Figure Two for images of orthotics)
External links
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- Textbook of Hallux Valgus and Forefoot Surgery,links to complete text in PDF files