Hallux Varus 735.1

synonyms:

Hallux Varus ICD-9

•  735.1 Hallux varus (acquired)

Hallux Varus Etiology / Epidemiology / Natural History 

• Usually iatrogenic hallux varus, often associated with a bunionectomy that included a fibular sesamoidectomy.
• Asociated with a bunionectomy that included a fibular sesamoidectomy.   

Hallux Varus Anatomy

Hallux Varus Clinical Evaluation

Hallux Varus Xray / Diagnositc Tests

• Weightbearing AP view, lateral view, standing axial xrays.
• Evaluate MTP joint congruity and degree of arthritis.
• HV angle = angle between the long axes of the first metatarsal and proximal phalanx; normal<15 degrees. 
• intermetatarsal (IM) angle=angle between the first and second metatarsals; normal< 9 degrees  

Hallux Varus Classification / Treatment

• Hallux varus with painfree joint: Rx=dynamic correction using EHL or EHB. 
• Tenodesis-type transfer of the extensor hallucis brevis.  The tendon is cut at its musculotendinous junction and transferred beneath the transverse metatarsal ligament proximally into the lateral aspect of the first metatarsal.  Medial release of the abductor hallucis and medial capsule may also be necessary.  The transfer is a static tenodesis and does not function dynamically.  Myerson MS, Komenda GA: Results of hallux varus correction using an extensor hallucis brevis tenodesis.  Foot Ankle Int 1996;17:21-27.
• If IP joint does not have fixed deformity a split EHL transfer with medial capsulotomy can be used. (Johnson KA, Spiegl PV: Extensor hallucis longus transfer for hallux varus deformity.  J Bone Joint Surg 1984;66A:681-686)
• Hallux varus with arthritic joint: Rx= arthrodesis(Ouzounian Foot Ankle Clin 2:741;1997).  
• Hallux Varus with translation of the metatarsal head:  if prior bunion correction caused excessive translation of the metatarsal head, osteotomy is required to place proximal phalanx in a congruent position.  Medial capsule release and splint extensor hallucis longus transfer into the proximal phalanx, under the intermetatarsal ligament laterally. 

Hallux Varus Associated Injuries / Differential Diagnosis

• Hallux Valgus Interphalangeus
• Hallux Valgus

Hallux Varus Complications

• Nonuion
• Infection
• Painful hardware
• Compartment Syndrome
• CRPS
• DVT / PE

Hallux Varus Follow-up Care

Hallux Varus Review References

• Johnson KA, Spiegl PV. Extensor hallucis longus transfer for hallux varus deformity. J Bone Joint Surg Am. 1984 Jun;66(5):681-6
• Ouzounian Foot Ankle Clin 2:741;1997
• Myerson MS, Komenda GA: Results of hallux varus correction using an extensor hallucis brevis tenodesis.  Foot Ankle Int 1996;17:21-27
• Johnson KA, Spiegl PV: Extensor hallucis longus transfer for hallux varus deformity.  J Bone Joint Surg 1984;66A:681-686