Changes

July to August 2021 — reviewed. A literature search was conducted in July 2021 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials published since the last revision of the topic. The section on Assessment has been moved to the Diagnosis section to improve clarity and navigation. An additional section on Surgical management has been added to the Management section. The basis for recommendation sections have been updated with current evidence in the literature. No major changes to clinical recommendations have been made.

Update

Goals

To support primary healthcare professionals to:

• Accurately diagnose and assess bunions.
• Provide appropriate information and advice on self-management.
• Offer appropriate treatment options in primary care.
• Arrange specialist referral to podiatry and/or orthopaedic surgery if clinically indicated.

Outcome measures

No outcome measures were found during the review of this topic.

Audit criteria

No audit criteria were found during the review of this topic.

QOF indicators

No QOF indicators were found during the review of this topic.

QIPP - options for local implementation

No QIPP indicators were found during the review of this topic.

NICE quality standards

No NICE quality standards were found during the review of this topic.

What is it?

• A bunion (hallux valgus) describes a toe deformity when the great toe (hallux) laterally deviates away from the midline towards the lesser toes. This causes medial prominence of the first metatarsal head, and the overlying bursa and soft tissues may also become inflamed [Choa, 2010; Hecht, 2014; RCS, 2017; Ray, 2019; Andrews, 2021].
  • A bunion can cause altered joint mechanics, and pain when walking or wearing shoes [RCS, 2017; Ray, 2019].
  • Lateral deviation of the proximal phalanx from the first metatarsal (hallux valgus angle) greater than 15 degrees and an intermetatarsal angle greater than 9 degrees on weight-bearing X-rays are considered abnormal [Choa, 2010; Hecht, 2014; Ray, 2019].

What causes it?

The exact cause of bunion development is not well understood. Predisposing factors may include:

• Poorly-fitting and constricting footwear — high heels or shoes with tight-fitting toe boxes may cause increased first metatarsal loading and valgus stress at the first metatarsophalangeal (MTP) joint as the foot slides forwards into the narrow toe-box during walking [Choa, 2010; Nix, 2012; Hecht, 2014; Fraissler, 2016; Ray, 2019; Andrews, 2021].
• Increasing age — due to altered joint mechanics and plantar loading patterns [Ray, 2019].
• Female gender — may be related to differences in footwear, bony anatomy, and ligamentous laxity [Hecht, 2014; Fraissler, 2016; Park, 2019; Ray, 2019].
• Family history — the exact inheritance pattern is unclear [Choa, 2010; Hecht, 2014; Fraissler, 2016; Ray, 2019]. An autosomal dominant with incomplete penetrance mechanism has been implicated in some studies [Andrews, 2021].
• Pes planus (loss of the medial longitudinal arch or 'flat foot') — this may co-exist due to increased pronation of the great toe [Choa, 2010]  [Hecht, 2014; Fraissler, 2016; Ray, 2019]. Other foot deformities such as metatarsus adductus, equinus contracture, and hammer toe deformity may also co-exist [Ray, 2019].
• Achilles tendon contracture — this causes increased forefoot pronation and increased valgus forces on the foot [Choa, 2010; Hecht, 2014; Ray, 2019].
• The length of the first metatarsal [Ray, 2019].
• Ligamentous laxity [Ray, 2019].
• Neuromuscular disorders — such as cerebral palsy and stroke [Hecht, 2014].

How common is it?

Bunions are the most common forefoot problem presenting in adults [Hecht, 2014].

• The exact prevalence of bunions is unknown, but it increases with age. A systematic review and meta-analysis of 76 international prevalence surveys (n = 496,957) found [Nix, 2010]:
  • A pooled prevalence estimate of 23% in adults aged 18–65 years, and 35.7% in people aged 65 years and older.
  • A higher prevalence of bunions in women (30%) compared with men (13%).

What are the complications?

Possible complications of untreated bunions include:

• Forefoot and/or great toe pain [RCS, 2017; Andrews, 2021].
• Difficulty finding comfortable footwear [Hecht, 2014; Andrews, 2021].
• Callus or corn formation (at points of overload) such as under the second metatarsophalangeal (MTP) joint [Choa, 2010; RCS, 2017].
• Osteoarthritis of the first MTP joint (hallux rigidus) [Andrews, 2021]. See the CKS topic on Osteoarthritis for more information.
• Impaired balance and increased risk of falls [RCS, 2017; Andrews, 2021]. See the CKS topic on Falls - risk assessment for more information.
• Subluxation of the first MTP joint if hallux valgus is severe [Hecht, 2014; Park, 2019].
• Dislocation or dorsal subluxation at the second MTP joint ('hammer toe') [Choa, 2010; RCS, 2017; Ray, 2019; Andrews, 2021].
• Skin breakdown and foot ulceration (at points of overload) and risk of osteomyelitis, particularly in people with diabetes mellitus and associated peripheral neuropathy [Choa, 2010; RCS, 2017]. See the CKS topics on Diabetes - type 1 and Diabetes - type 2 for more information.

What is the prognosis?

The prognosis of bunions is uncertain, but toe deformity is often progressive [Hecht, 2014]:

• There may be a slow rate of progression of deformity [Choa, 2010].
• A retrospective longitudinal analysis of 268 adults with hallux valgus found that 17% of participants had a progressive deformity with an increase in the hallux valgus angle of 5 degrees or more after a median follow-up period of 49 months [Shinohara, 2021].
  • A large hallux valgus angle on X-ray at baseline was an independent risk factor for progression of the deformity.

When should I suspect a bunion deformity?

Suspect a bunion deformity if a person presents with:

• Progressive pain at the medial aspect of the first metatarsophalangeal (MTP) joint and/or medial aspect of the forefoot.
• Difficulty wearing shoes.
• Lateral deviation of the hallux at the first MTP joint. 
• Medial prominence of the first metatarsal head.

How should I assess a person with a bunion?

If a person has a bunion based on initial clinical features:

• Ask about:
  
  • The presence and duration of symptoms such as forefoot and/or first metatarsophalangeal (MTP) medial joint pain, which may be worse when wearing shoes and weight-bearing.
  • The impact on walking and the person's lifestyle and activities.
  • Any difficulty fitting into footwear; footwear normally worn; any recent changes in footwear.
  • Any family history.
  • Comorbid vascular disease or neuropathy.
  • Any previous treatments.
• Observe the person's gait and lower leg alignment.
• Examine the person's foot/feet in a standing and seated position.
  • Assess the degree of hallux deformity and presence of pes planus while the person is standing.
  • Assess skin quality and examine for associated complications such as calluses, corns, bursitis, skin breakdown, and lesser toe deformities.
  • Palpate the first MTP joint, lesser toes, and forefoot for areas of pain and tenderness.
  • Assess for neurovascular insufficiency.
  • Assess the range of movement of the first MTP joint, other foot joints, and ankle — stiffness and rigidity of the first MTP joint may indicate associated osteoarthritis.
  • Examine for ligamentous laxity or contractures.
• Examine the type and wear patterns of footwear and assess shoe fit.
• Do not routinely arrange foot X-ray in primary care.

What else might it be?

Alternative conditions which may present similarly to a bunion deformity include:

• Hallux rigidus — osteoarthritis of the metatarsophalangeal (MTP) joint typically causes joint pain, swelling, stiffness, and rigidity. See the CKS topic on Osteoarthritis for more information.
• Hallux interphalangeus — the tip of the great toe is deviated laterally.
• Gout. See the CKS topic on Gout for more information.
• Chronic sesamoiditis — this may affect people who undergo repetitive jumping or running; there is typically gradual onset toe pain below the first MTP joint that is worse on weight-bearing; there may be pronounced wear on the forefoot of the shoe.
• Fracture — may present with joint deformity and point tenderness.
• Inflammatory joint disease, such as rheumatoid arthritis. See the CKS topic on Rheumatoid arthritis for more information.
• Peripheral neuropathy — there may be a high-stepping gait with reduced lower extremity reflexes and sensation. See the CKS topics on Diabetes - type 1 and Diabetes - type 2 for more information.
• Osteomyelitis — there may be joint redness, swelling, severe pain and tenderness, and the person may be systemically unwell.

Scenario: Bunions

From age 18 years onwards.

Search strategy

Scope of search

A literature search was conducted for guidelines, systematic reviews and randomized controlled trials on primary care management of bunions.

Search dates

July 2016 – June 2021

Key search terms

Various combinations of searches were carried out. The terms listed below are the core search terms that were used for Medline.

• exp Hallux Valgus/, (hallux ADJ valgus).tw., (hallux ADJ abductovalgus).tw., bunion$.tw.
• exp metatarsophalangeal joint/
• orthotic devices/
• splints/
• (bunion$ or hallux valgus).ti,ab.

Sources of guidelines

• National Institute for Health and Care Excellence (NICE)
• Scottish Intercollegiate Guidelines Network (SIGN)
• Royal College of Physicians
• Royal College of General Practitioners
• Royal College of Nursing
• NICE Evidence
• World Health Organization
• Guidelines International Network
• TRIP database
• Agency for Healthcare Research and Quality
• Institute for Clinical Systems Improvement
• National Health and Medical Research Council (Australia)
• Royal Australian College of General Practitioners
• British Columbia Medical Association
• Canadian Medical Association
• Alberta Medical Association
• Michigan Quality Improvement Consortium
• Singapore Ministry of Health
• National Resource for Infection Control
• RefHELP NHS Lothian Referral Guidelines
• Medline (with guideline filter)
• Driver and Vehicle Licensing Agency
• NHS Health at Work (occupational health practice)

Sources of systematic reviews and meta-analyses

• The Cochrane Library:
  • Systematic reviews
  • Protocols
  • Database of Abstracts of Reviews of Effects
• Medline (with systematic review filter)
• EMBASE (with systematic review filter)

Sources of health technology assessments and economic appraisals

• NIHR Health Technology Assessment programme
• The Cochrane Library:
  • NHS Economic Evaluations
  • Health Technology Assessments
• Canadian Agency for Drugs and Technologies in Health
• International Network of Agencies for Health Technology Assessment

Sources of randomized controlled trials

• The Cochrane Library:
  • Central Register of Controlled Trials
• Medline (with randomized controlled trial filter)
• EMBASE (with randomized controlled trial filter)

Sources of evidence based reviews and evidence summaries

• Bandolier
• Drug and Therapeutics Bulletin
• TRIP database
• Central Services Agency COMPASS Therapeutic Notes

Sources of national policy

• Department of Health
• Health Management Information Consortium (HMIC)

Patient experiences

• Healthtalk
• BMJ - Patient Journeys

Sources of medicines information

The following sources are used by CKS pharmacists and are not necessarily searched by CKS information specialists for all topics. Some of these resources are not freely available and require subscriptions to access content.

• British National Formulary (BNF)
• electronic Medicines Compendium (eMC)
• European Medicines Agency (EMEA)
• LactMed
• Medicines and Healthcare products Regulatory Agency (MHRA)
• REPROTOX
• Scottish Medicines Consortium
• Stockley's Drug Interactions
• TERIS
• TOXBASE
• Micromedex
• UK Medicines Information

Stakeholder engagement

Our policy

The external review process is an essential part of CKS topic development. Consultation with a wide range of stakeholders provides quality assurance of the topic in terms of:

• Clinical accuracy.
• Consistency with other providers of clinical knowledge for primary care.
• Accuracy of implementation of national guidance (in particular NICE guidelines).
• Usability.

Principles of the consultation process

• The process is inclusive and any individual may participate.
• To participate, an individual must declare whether they have any competing interests or not. If they do not declare whether or not they have competing interests, their comments will not be considered.
• Comments received after the deadline will be considered, but they may not be acted upon before the clinical topic is issued onto the website.
• Comments are accepted in any format that is convenient to the reviewer, although an electronic format is encouraged.
• External reviewers are not paid for commenting on the draft topics.
• Discussion with an individual or an organization about the CKS response to their comments is only undertaken in exceptional circumstances (at the discretion of the Clinical Editor or Editorial Steering Group).
• All reviewers are thanked and offered a letter acknowledging their contribution for the purposes of appraisal/revalidation.
• All reviewers are invited to be acknowledged on the website. All reviewers are given the opportunity to feedback about the external review process, enabling improvements to be made where appropriate.

Stakeholders

• Key stakeholders identified by the CKS team are invited to comment on draft CKS topics. Individuals and organizations can also register an interest to feedback on a specific topic, or topics in a particular clinical area, through the Getting involved section of the Clarity Informatics website.
• Stakeholders identified from the following groups are invited to review draft topics:
  • Experts in the topic area.
  • Professional organizations and societies (for example, Royal Colleges).
  • Patient organizations, Clarity has established close links with groups such as Age UK and the Alzheimer’s Society specifically for their input into new topic development, review of current topic content and advice on relevant areas of expert knowledge.
  • Guideline development groups where the topic is an implementation of a guideline.
  • The British National Formulary team.
  • The editorial team that develop MeReC Publications.
• Reviewers are provided with clear instructions about what to review, what comments are particularly helpful, how to submit comments, and declaring interests.

Patient engagement

Clarity Informatics has enlisted the support and involvement of patients and lay persons at all stages in the process of creating the content which include:

• Topic selection
• Scoping of topic
• Selection of clinical scenarios
• First draft internal review
• Second draft internal review
• External review
• Final draft and pre-publication

Our lay and patient involvement includes membership on the editorial steering group, contacting expert patient groups, organizations and individuals.

Evidence exclusion criteria

Our policy

Scoping a literature search, and reviewing the evidence for CKS is a methodical and systematic process that is carried out by the lead clinical author for each topic. Relevant evidence is gathered in order that the clinical author can make fully informed decisions and recommendations. It is important to note that some evidence may be excluded for a variety of reasons. These reasons may be applied across all CKS topics or may be specific to a given topic.

Studies identified during literature searches are reviewed to identify the most appropriate information to author a CKS topic, ensuring any recommendations are based on the best evidence. We use the principles of the GRADE and PICOT approaches to assess the quality of published research. We use the principles of AGREE II to assess the quality of published guidelines.

Standard exclusions for scoping literature:

• Animal studies
• Original research is not written in English

Possible exclusions for reviewed literature:

• Sample size too small or study underpowered
• Bias evident or promotional literature
• Population not relevant
• Intervention/treatment not relevant
• Outcomes not relevant
• Outcomes have no clear evidence of clinical effectiveness
• Setting not relevant
• Not relevant to UK
• Incorrect study type
• Review article
• Duplicate reference

Organizational, behavioural and financial barriers

Our policy

The CKS literature searches take into consideration the following concepts, which are discussed at the initial scoping of the topic.

• Feasibility
  • Studies are selected depending on whether the intervention under investigation is available in the NHS and can be practically and safely undertaken in primary care.
• Organizational and Financial Impact Analysis
• Studies are selected and evaluated on whether the intervention under investigations may have an impact on local clinical service provision or national impact on cost for the NHS. The principles of clinical budget impact analysis are adhered to, evaluated and recorded by the author. The following factors are considered when making this assessment and analysis.
  • Eligible population
  • Current interventions
  • Likely uptake of new intervention or recommendation
  • Cost of the current or new intervention mix
  • Impact on other costs
  • Condition-related costs
  • In-direct costs and service impacts
  • Time dependencies
• Cost-effectiveness or cost-benefit analysis studies are identified where available. 

We also evaluate and include evidence from NICE accredited sources which provide economic evaluations of recommendations, such as NICE guidelines. When a recommended action may not be possible because of resource constraints, this is explicitly indicated to healthcare professionals by the wording of the CKS recommendation.

Declarations of interest

Our policy

Clarity Informatics requests that all those involved in the writing and reviewing of topics, and those involved in the external review process to declare any competing interests. Signed copies are securely held by Clarity Informatics and are available on request with the permission of the individual. A copy of the declaration of interest form which participants are asked to complete annually is also available on request. A brief outline of the declarations of interest policy is described here and full details of the policy is available on the Clarity Informatics website. Declarations of interests of the authors are not routinely published, however competing interests of all those involved in the topic update or development are listed below. Competing interests include:

• Personal financial interests
• Personal family interest
• Personal non-financial interest
• Non-personal financial gain or benefit

Although particular attention is given to interests that could result in financial gains or losses for the individual, competing interests may also arise from academic competition or for political, personal, religious, and reputational reasons. An individual is not obliged to seek out knowledge of work done for, or on behalf of, the healthcare industry within the departments for which they are responsible if they would not normally expect to be informed.

Who should declare competing interests?

Any individual (or organization) involved in developing, reviewing, or commenting on clinical content, particularly the recommendations should declare competing interests. This includes the authoring team members, expert advisers, external reviewers of draft topics, individuals providing feedback on published topics, and Editorial Steering Group members. Declarations of interest are completed annually for authoring team and editorial steering group members, and are completed at the start of the topic update and development process for external stakeholders.

Competing interests declared for this topic:

None.