Review Question - QID 211506

The patient presents with a hallux varus deformity one year after undergoing correction of hallux valgus due to complete excision of the medial eminence.

There are several known complications following hallux valgus correction. Recurrence may occur due to patient noncompliance with post-operative weight-bearing restrictions, residual sesamoid displacement, increased post-operative IMA, and failure to follow indications (i.e., distal osteotomy when proximal is indicated based on preoperative imaging). Residual displacement of the sesamoids following surgery is a good radiographic indicator of impending hallux valgus recurrence. Other complications include avascular necrosis due to medial blood supply damage, cock-up toe deformity due to flexor hallucis longus injury, neuropraxia due to medial dorsal cutaneous nerve damage, and transfer metatarsalgia due to excessive first metatarsal shortening.

Perera et al. review the pathogenesis of hallux valgus. They report that essential early lesion causing hallux valgus is the failure of the medial sesamoid and medial collateral ligaments. They conclude that hallux valgus deformity is due to the parallel deformation of the soft tissue structures surrounding the first metatarsophalangeal joint complex and sesamoid displacement.

Bevernage et al. reviewed the classification and treatment of hallux varus. They report that hallux varus is most commonly seen as an iatrogenic complication of hallux valgus surgery either due to a loss of bony support or soft tissue imbalance. They conclude that early post-operative recognition of iatrogenic hallux varus is critical as nonoperative treatments such as taping may correct the deformity.

Figure A demonstrates a hallux valgus deformity with hallux valgus angle (HVA) of 45 degrees, and IMA of 16 degrees.

Incorrect Answers
Answer 1: Performance of a lateral sesamoidectomy, not medial, is a risk factor for the development of hallux varus deformity.
Answer 2: Complete release of the adductor hallucis (and lateral soft tissue structures) may result in hallux varus deformity.
Answer 3: Normal IMA is less than 9 degree and overcorrection of the IMA often results in hallux varus. An post-operative IMA of 15 degrees would risk hallux valgus recurrence.
Answer 5: Excessive medial capsulorrahaphy is associated with hallux varus deformity.