Contribution of First-Tarsometatarsal Joint Fusion to Deformity Correction in the Treatment of Adult-Acquired Flatfoot Deformity

Abstract

Background: Severe adult-acquired flatfoot deformity (AAFD) is often associated with painful medial column collapse at the naviculocuneiform (NC) joint. However, many surgeons surgically correct the deformity without directly addressing this joint. The purpose of this study was to examine the role of first-tarsometatarsal (TMT) fusion combined with subtalar fusion in correcting deformity at the NC joint. Methods: We retrospectively analyzed 40 patients (41 feet) who underwent first-TMT and subtalar (ST) fusion as part of a flatfoot reconstructive procedure. We assessed 6 radiographic parameters both preoperatively and at a minimum of 6 months postoperatively, including talonavicular (TN) coverage angle, lateral talo–first metatarsal angle, lateral talocalcaneal angle, calcaneal pitch, hindfoot moment arm, and a newly defined navicular-cuneiform incongruency angle (NCIA). Patient-Reported Outcomes Measurement Information System (PROMIS) clinical outcomes were assessed preoperatively and at a minimum 1-year follow-up. Results: The NCIA demonstrated excellent interobserver reliability, with no significant change between pre- and postoperative measurements. All other radiographic parameters, except calcaneal pitch, demonstrated statistically significant improvement postoperatively ( P < .01). Overall, patients had statistically significant improvement in all PROMIS domains ( P < .01), except for depression. Worsening NC deformity was not associated with worse patient-reported outcomes. Conclusions: Our data suggest that when addressing painful collapse of the medial arch in patients with AAFD, fusion of the first-TMT joint in combination with other procedures leads to acceptable radiographic and clinical outcomes. There was no change in deformity at the NC joint in our patient cohort at short-term follow-up, and patients achieved significant improvement in multiple PROMIS domains. Although TMT fusion had no effect on NC deformity, residual or worsening NC deformity did not significantly affect clinical outcomes. In addition, the NCIA was found to be a reliable radiographic parameter to assess NC deformity in the presence of talonavicular and/or first-TMT fusion. Level of Evidence: Level III, retrospective comparative study.

Does the Presence of Asymptomatic Flatfoot Deformity Impact the Clinical and Radiographic Outcomes of the Minimally Invasive Chevron and Akin Bunionectomy?

“…Although the MIS bunionectomy appears to correct hallux valgus in the presence of asymptomatic flatfoot, proximal procedures such as the Lapidus still have a role for more severe hallux deformities and as part of a flatfoot reconstruction. 15,20,43 Since the Lapidus provides a reliable medial support at the first TMT joint, it could be preferred when the flatfoot is more apparent or when there is obvious clinical first ray hypermobility. 3,18,37 When the hallux valgus deformity is so large or the TMT motion so great that even with 100% shift of the metatarsal head the TMT joint is still mobile, the risk of recurrence with a metatarsal osteotomy is great.…”

Peroneus Brevis to Longus Tendon Transfer in the Treatment of Flexible Progressive Collapsing Foot Deformity: A Cadaveric Study

“…11 An opening wedge medial cuneiform osteotomy, a first tarsometatarsal fusion, or a naviculocuneiform fusion have all been used to plantarflex the first ray and provide stability to the medial column. 4,6,7,16 Tendon transfers have recently been proposed to support the medial column in flexible PCFD dynamically. 17,28 A transfer of the peroneus brevis (PB) tendon to the peroneus longus (PL) tendon is one such transfer that has been suggested to correct the flexible forefoot varus deformity in PCFD.…”