# Tendoscopy-Assisted Flexor Digitorum Longus Transfer and Spring Ligament Synthetic Suture Tape Reconstruction for Flexible Progressing Collapsing Foot Deformity

## TL;DR

A new minimally invasive surgical technique is proposed for treating flexible progressive collapsing foot deformity by combining tendon transfer and spring ligament reconstruction.

## Contribution

A novel tendoscopic-assisted technique with spring ligament synthetic suture tape reconstruction is introduced for minimally invasive foot deformity correction.

## Key findings

- The technique allows fully minimally invasive reconstruction of flexible progressive collapsing foot deformity.
- Spring ligament augmentation improves resistance to forefoot lateralization and radiographic outcomes.
- Combining tendon transfer with ligament reconstruction may enhance correction potential.

## Abstract

Progressive collapsing foot deformity is a complex deformity that is predisposed to by weakening and elongation of the spring ligament, resulting in peritalar subluxation. A medializing calcaneal osteotomy and flexor digitorum longus tendon transfer are standard surgical procedures for a symptomatic flexible deformity that is recalcitrant to nonoperative treatment. Endoscopic-assisted flexor digitorum longus transfer and a minimally invasive medializing calcaneal osteotomy, allow a fully minimally invasive approach to address flat foot reconstruction. Concerns remain regarding low correction potential, lack of medial longitudinal arch reconstitution, and a lack of improvement of forefoot abduction without surgically addressing the attenuated spring ligament. Spring ligament augmentation with an internal brace provides benefits of high resistance to forefoot lateralization, reliably improved radiographic parameters, and patient-reported outcomes. We describe a tendoscopic-assisted flexor digitorum longus tendon transfer and a spring ligament synthetic suture tape reconstruction technique, used in conjunction with a medializing calcaneal osteotomy. This technique allows a completely minimally invasive approach to flexible progressive collapsing foot deformity reconstruction, with increased resistance to forefoot lateralization and the potential to more reliably improve and preserve radiographic parameters.