First Tarsometatarsal Alignment May Self-Correct After Triple Arthrodesis in Progressive Collapsing Foot Deformity

Area of Science:

• Orthopedic surgery
• Foot and ankle reconstruction
• Biomechanical analysis of foot deformities

Background:

• Progressive collapsing foot deformity (PCFD) often presents with concurrent first tarsometatarsal (TMT) joint instability.
• The necessity of adding first TMT arthrodesis to triple arthrodesis for PCFD correction remains debated.
• This study investigates the efficacy of isolated triple arthrodesis in managing PCFD with TMT instability.

Purpose of the Study:

• To evaluate the effectiveness of isolated triple arthrodesis in correcting first TMT instability in patients with PCFD.
• To determine if triple arthrodesis alone is sufficient for managing medial column instability associated with PCFD.
• To assess the long-term radiographic outcomes of triple arthrodesis for PCFD with TMT instability.

Main Methods:

• Retrospective review of 20 patients with PCFD and first TMT instability treated with triple arthrodesis alone between 2013 and 2021.
• Pre- and postoperative weightbearing radiographs were analyzed for first TMT joint instability.
• Measurements included the sagittal first metatarsal-medial cuneiform angle and first metatarsal subluxation.

Main Results:

• Fourteen of twenty patients (70%) showed correction of first TMT instability after isolated triple arthrodesis.
• Radiographic improvements were maintained at an average 5-year follow-up.
• The first metatarsal-medial cuneiform angle improved from 3.8 to 1.1 degrees (P < .05), and subluxation corrected from 4.1 to 1.5 mm (P < .05).

Conclusions:

• Isolated triple arthrodesis can effectively correct radiographic first TMT instability in a majority of PCFD patients.
• This technique provides durable correction, maintaining alignment at a mean 5-year follow-up.
• Triple arthrodesis alone may be sufficient for addressing medial column instability in PCFD.