summary Hallux Varus is a condition characterized by the medial deviation of the hallux relative to the 1st metatarsal bone, most often the result of overcorrection from prior bunion surgery. Diagnosis is made clinically with varus angulation of the great toe. Treatment may be observation or operative depending on severity of varus, prior surgeries to the hallux, and patient symptoms. Epidemiology Incidence varies between 2-14% after corrective surgery for hallux valgus deformities Demographics more commonly seen in women Etiology Pathophysiology causes congenital metatarsal physeal bracket acquired iatogenic (overcorrection from surgery) trauma inflammatory (e.g. rheumatoid arthritis, ankylosis spondylitis) neurological (e.g. Charcot-Marie-Tooth, post-polio) pathoanatomy loss of osseous support excessive resection of the medial eminence excision of fibular (lateral) sesamoid overrelease of lateral capsular structures overplication of medial capsule overtranslation of intermetatarsal angle or hallux valgus interphalangeus Orthopaedic manifestations hallux varus usually presents with three possible components medial deviation of the hallux relative to first MTP joint supination of the phalanx claw toe deformity Presentation History main complaint appearance of the great toe as being "too straight" to excessive medial deviation difficulty wearing shoes Symptoms often asymptomatic pain indicates underlying joint arthritis or trauma may also complain of decreased ROM, instability, weakness with push-off Physical exam inspection varus anglulation of great toe dorsal contracture of the MTP joint with or without IP joint contracture EHL may be medially displaced, creating a "bowstring" deformity tibial (medial) sesamoid may be medially displaced motion determine if fixed or flexible deformity Imaging Radiographs recommended views weight-bearing AP & lateral views of the foot, additional views non-weightbearing oblique views, and sesamoid axial views findings hallux valgus angle < 0 degrees (normal 5-15 degrees) excessive medial eminence resection overcorrection osteotomies reduced IMA between first and second metatarsals medial subluxation of tibial seasmoid absent lateral seasmoid degenerative changes at MTP or IP joint CT scan or MRI indications not usually required may be considered if underlying osteonecrosis of first metatarsal Treatment Nonoperative shoe modifications to accommodate the deformity indications flexible, longstanding and asymptomatic deformities patient preference modalities wider and more flexible toe box shoes padding boney prominences outcomes mild flexible and stable deformities are usually well tolerated taping or splinting the deformity indications early post-operative varus deformities after hallux correction surgery modalities frequent taping and follow-up duration should be maintained for up to 3 months or until soft-tissues have healed outcomes may correct deformity if initiated within the first few weeks from surgery Operative lateral closing wedge osteotomy indications overcorrection of proximal/distal metatarsal osteotomy, or proximal phalangeal osteotomy techniques revision osteotomy to re-establish alignment consider release of scar tissue and repair of the lateral ligaments tendon transfer with medial release indications flexible first MTP joint deformities techniques aDDuctor hallucis tendon re-attachment with medial release may be difficult in cases of previous McBride-type surgery aBDuctor hallucis tendon transfer on the base of the lateral base of proximal phalanx combined with the reattachment or reefing of the conjoined tendon in the web space transfer or EHL or EHB, medial release, with or without IP joint arthrodesis transfer portion of EHL or EHB under the transverse intermetatarsal ligament to the distal metatarsal neck (from lateral to medial) first MTP arthrodesis indications absolute fixed (not passively correctable) first MTP joint with significant deformity and non-functioning hallux painful joint arthritis relative excessive medial eminence resection beyond tibial seasmoid sulcus Prognosis Natural history of disease in established hallux varus, the role of nonoperative management is limited