Also found in: Dictionary, Encyclopedia.
hallux abductovalgus; HAV biplanar first-ray deformity, where the tip of the hallux is deviated on the transverse plane (away from body midline) in conjunction with frontal-plane axial rotation of the hallux about its longitudinal axis (i.e. the medial nail sulcus approaches the support surface) and transverse-plane deviation of the first metatarsal head towards the midline of the body (i.e. secondary to metatarsus primus varus); HAV is associated with a range of forefoot pathologies (Table 1 and Box 1; Figure 1) and may require surgical correction Table 2
|Intrinsic to the foot and lower limb||Excess STJ and MTJ pronation||Ankle equinus|
Metatarsus primus elevatus
Metatarsus primus varus
Long second metatarsal/short first metatarsal
Functional hallux limitus
|Structural anomalies within the lower limb that predispose to compensatory foot pronation||External tibial torsion|
Genu varum/valgum, recurvatum
|Trauma||First MTPJ intra-articular damage|
First MTPJ sprain (turf toe)
Subluxed second toe
|Extrinsic to the foot and lower limb||Inflammatory joint disease||Rheumatoid disease|
|Connective tissue disorders characterized by joint hypermobility||Generalized hypermobility syndrome|
|Neuromuscular disease characterized by the development of pes cavus or pes planovalgus||Multiple sclerosis|
Hereditary sensorimotor neuropathy (Charcot-Marie-Tooth disease)
STJ, subtalar joint; MTJ, metatarsal joint; MTPJ, metatarsophalangeal joint.
|Good||The sheet of paper remains static and in situ when pulled|
|Fair||The sheet of paper moves slightly when pulled, but tends to tear when greater traction is applied|
|Poor||The sheet of paper can be pulled out with minimum effort|
|Absent||The paper slips out easily; it is not retained by the hallux as the pulp of the toe does not make ground contact|
Hallux purchase is inferred by the ease with which a sheet of paper can be pulled out from beneath the pulp of the weight-bearing hallux.
|Surgical approach||Intervention||Example procedure|
|Joint-destructive procedures||Excision of base of hallux proximal phalanx|
|Joint-preserving procedures||Closing basal wedge osteotomy, first metatarsal|
Distal metatarsal osteotomy
|Basal wedge osteotomy|
|Ray alignment procedures||Z osteotomy|
Medial closing-wedge osteotomy, hallux
|Ray stabilization procedures||Arthrodesis of first metatarsal/medial cuneiform joint||Lapidus|
|Cosmesis||Excision of medial eminence at head of first metatarsal (cheilectomy)||Silver|
There are over 100 named surgical techniques for the correction of hallux abductovalgus, most of which are modifications of a number of principles of approach.