Intraoperative evaluation of medial intercuneiform instability after Lapidus arthrodesis: intercuneiform hook test

Area of Science:

• Orthopedic surgery
• Podiatric surgery
• Foot and ankle biomechanics

Background:

• Intercuneiform instability is often overlooked in hallux valgus surgical management.
• This oversight may lead to underreporting and recurrence of hallux valgus deformities.
• Proximal instability can significantly impact the success of hallux valgus correction.

Purpose of the Study:

• To determine the incidence of intercuneiform instability in hallux valgus patients.
• To emphasize the importance of addressing proximal instability in surgical correction.
• To present a technique for evaluating intercuneiform instability post-arthrodesis.

Main Methods:

• Retrospective review of 34 patients (38 procedures) undergoing tarsometatarsal arthrodesis for hallux valgus.
• Intraoperative "hook" test used to assess intercuneiform instability.
• Follow-up period of 36 months (May 2007 to May 2010).

Main Results:

• Intercuneiform instability was identified in 73.68% of the reviewed cases.
• A high incidence of proximal instability was observed in patients with moderate to severe intermetatarsal angles and hypermobility.
• The "hook" test proved effective in diagnosing this instability.

Conclusions:

• The high prevalence of intercuneiform instability suggests it is a critical factor in hallux valgus recurrence.
• Routine evaluation for proximal instability should be considered in surgical hallux valgus correction.
• Intermetatarsal arthrodesis may be a necessary component for definitive hallux valgus management.