Hallux Varus


Hallux varus is an uncommon condition, characterised by medial deviation of the hallux at the metatarsophalangeal (MTP) joint. Mild cases are often well tolerated but more severe deformity can lead to difficulties walking due to a loss of propulsion. There can also be difficulties finding shoes that fit.



Hallux varus can be congenital or acquired. The commonest cause is iatrogenic, as a complication of hallux valgus correction, which occurs in 2-14% of cases.


  • Newborn flexible hallux varus
    • due to intrauterine position
    • resolves without treatment
  • Primary hallux varus
    • increased abductor hallucis activity
  • Secondary hallux varus
    • big toe polydactyly
    • delta phalanx
    • metatarsus adductus


  • Iatrogenic
    • hallux valgus overcorrection
  • Systemic disease
    • inflammatory arthropathy
    • connective tissue disorder
  • Neuromuscular
    • e.g. cerebral palsy

Factors contributing to hallux varus after bunion surgery include:

      • Excessive lateral release
      • Over-resection of medial eminence
      • Over plication of medial capsule
      • Zero or negative inter-metatarsal angle
      • Immobilisation of the toe in excessive varus post-operatively



The deformity is often associated with imbalance between the abductor and adductor hallucis muscles. This can cause the deformity to progress over time. The MTP joint may become stiff and arthritic. With severe, long-standing deformity, imbalance between flexor hallucis brevis (FHB) and extensor hallucis brevis (EHB) muscles can cause interphalangeal (IP) joint contracture. If there is a moderate or severe varus deformity, eventually the lesser toes can also become deformed.


Non-operative management

  • Patient education: explanation and advice on appropriate footwear
  • Shoe stretching and padding of bony prominences

For early post-operative varus due to over-plication of the medial capsule or excessive lateral release, initial treatment should consist of splinting or taping. This is continued for 12 weeks to stretch and support the soft tissues as they heal.


Operative management

Multiple procedures have been described to correct hallux varus. Consideration of the following factors can help choose the most appropriate option.

  • Is the deformity fixed or correctable?
    • Assess this both seated and when weight bearing
  • How severe is the deformity?
  • Is the first MTP joint or IP joint arthritic?
  • Are the lesser toes involved

Flexible deformity can usually be addressed with a soft tissue procedure:

  • medial capsule release; in mild cases this may be adequate
  • abductor tendon release or…
  • abductor tendon transfer under MT head into base of the proximal phalanx laterally
  • reattachment of the adductor hallucis tendon has been described, if the deformity was caused by over-zealous lateral release
  • EHB or the lateral portion of EHL transfer:
    • divide proximally
    • pass free end around the inter-metatarsal ligament in the first webspace
    • suture back on itself to provide a ‘check rein’ or
    • tenodese into a tunnel in the metatarsal
  • interphalangeal joint arthrodesis, with EHL then transferred to the PP base
  • suture button or tightrope implant can be used to augment the repair

Fixed or bony deformity of the first metatarsal (including over-correction of the inter-metatarsal angle) will require bony correction:

  • revision osteotomy
  • first TMT joint corrective arthrodesis
  • MTP joint arthrodesis
  • interposition arthroplasty of the MTP joint; may be combined with IP joint fusion if there is fixed deformity or arthritis affecting both MTP and interphalangeal joints
  • reverse Akin (or opening wedge osteotomy at PP base)

Lesser toe deformities which have developed secondary to the hallux varus may require metatarsal shortening osteotomies to de-tension the intrinsic muscles.



  • Myerson MS, Kadakia AR. Reconstructive Foot and Ankle Surgery: Management of Complications. Third Edition, Elsevier 2019
  • Trnka HJ, Zettl R, Hungerford M, Mühlbauer M, Ritschl P. Acquired hallux varus and clinical tolerability. Foot Ankle Int. 1997 Sep;18(9):593-7. doi: 10.1177/107110079701800913
  • Leemrijse T, Devos Bevernage B. Surgical treatment of iatrogenic hallux varus. Orthop Traumatol Surg Res. 2020 Feb;106(1S):S159-S170. doi: 10.1016/j.otsr.2019.05.018. Epub 2019 Sep 11
  • Lau JT, Myerson MS. Modified split extensor hallucis longus tendon transfer for correction of hallux varus. Foot Ankle Int. 2002 Dec;23(12):1138-40. doi: 10.1177/107110070202301212