A Plantar Closing Wedge Osteotomy of The Medial Cuneiform for Residual Forefoot Supination in Flatfoot Reconstruction

SLR- January 2014- David Gelbmann

Reference: Ling J, Ross K, Hannon C, Egan C, Smyth N, Hogan M, Kennedy J. A Plantar Closing Wedge Osteotomy of the Medial Cuneiform for Residual Forefoot Supination in Flatfoot Reconstruction. Foot and Ankle International. 34(9);2013: 1221-1226.

Scientific Literature Review

Reviewed By: David Gelbmann, DPM
Residency Program: St. John Hospital and Medical Center

Podiatric Relevance: Stage II posterior tibialtendon dysfunction (PTTD) is a common podiatric pathology characterized by aflexible planovalgus deformity often including varus or instability of the medial column where by the medial arch sags, leading to progressive rearfoot valgus and ultimately forefoot supinatus. Stage II PTTD is commonly treated with joint sparing procedures such as medializing calcaneal osteotomy, flexordigitorum longus (FDL) tendon transfer, and lateral column lengthening. These interventions, however, often do not adequately address the forefoot supinatus component of the pes planovalgus. This study aims to describe and evaluate analternative surgical approach to correct varus or instability of the medialcolumn: a “reverse Cotton osteotomy” of the medial cuneiform, or plantarclosing wedge osteotomy of the medial cuneiform (PCWOMC). The authors believe that this procedure offers several advantages over the traditional Cottonosteotomy, and effectively addresses stage II PTTD when combined with medializing calcaneal osteotomy and FDL tendon transfer.

Methods: This was a level IV retrospective study of ten feet in nine patients who underwent a flatfoot reconstruction that included a plantar closing wedge osteotomy of the medial cuneiform (PCWOMC) as the last step of the reconstruction, that including FDL tendon transfer and medializing calcaneal osteotomy. All patients had forefoot supination both preoperative and intraoperatively as assessed with the hind foot in neutral and the talar head positioned to cover the navicular medially. Patients were excluded in the presence of medial column arthritis, or severe instability (dorsal-plantar movement of more than 10 degrees) of the medial column. All PCWOMC procedures were performed using the same medial incision as was used for the FDL tendon transfer. All involved resecting a 2 mm planarly based wedge of cuneiform bone, leaving the dorsal cortex intact. Correction was achieved when under intraoperative fluoroscopy the first and fifth metatarsal heads were level in the coronal plane. All osteotomies were fixated using two compression staples (Speed Staples, Biomedical Enterprises, Inc, San Antonio,TX). Each patient was assessed pre- and post operatively using the Foot and Ankle Outcome Score (FAOS) and Short Form-12 (SF-12) score. Standardized, validated radiographic parameters on pre- and postoperative weight-bearing radiographs were also measured, with final radiographs taken a minimum of six months following surgery.

Results: Patients were followed foran average of 25.8 months, with follow-up FAOS and SF-12 scores obtained at aminimum of 12 months post-operatively. There was one internal fixationcomplication presenting as pain localized to the medial cuneiform with a prominent plantar-medial staple, which was subsequently removed. There were no reported delayed or non-unions, and no evidence of tarsometatarsal or naviculocuneiform arthritis. Four subscales of the FAOS score showed statistically significant improvement, including: Pain, Sports and Recreation, and Quality of Life. The SF-12 score improved from an average pre-operative score of 48 to an average postoperative score of 68, which was statistically significant. A statistically significant difference between pre- and postoperative radiographic parameters was demonstrated for the mean lateraltalus-first metatarsal angle, which increased from -14.1 degrees preoperatively to -4.1 degrees postoperatively, and the mean medial-cuneiform-to-ground distance, which increased from 22.9 mm preoperatively to 27.3 mm postoperatively.

Conclusions: Stage II PTTD is a common pediatric pathology that often involves a component of forefoot supinatus, orvarus. Based on the above methods of evaluation, a plantar closing wedge osteotomy of the medial cuneiform is a strong alternative to the traditional Cotton osteotomy for the treatment of the forefoot supinatus component of flexible pes planovalgus. The main advantage of this technique is its simplicity, as an additional dorsal incision and use of a bone graft are obviated by this technique. However, when medial column arthritis or severe instability are present, arthrodesis is still recommended. Larger studies with longer follow-up and a stronger level of evidence would be warranted.