Short-Term Outcomes of the Lapicotton Technique in the Treatment of Progressive Collapsing Foot Deformity
Authors: Lalevée Matthieu , Mansur Nacime S. , Shamrock Alan G. , Lee Hee Young , Schmidt Eli , Vivtcharenko Victoria , Lintz Francois , Dibbern Kevin N. , Netto Cesar de Cesar 
Published: January 2022

Category: Midfoot/Forefoot Introduction/Purpose: Medial column instability (MCI) in Progressive Collapsing Foot Deformity (PCFD) is not solely determined by forefoot varus (FV). First ray hypermobility, hallux valgus, midfoot arthritis, gapping at the tarsometatarsal joint and dorsal metatarsal migration are findings associated with MCI. Acknowledgement of this instability requires inclusion of a procedure to the medial column in order to correct the forefoot varus, stabilize the ray and bring the foot to a plantigrade tripod position. Cotton opening wedge medial cuneiform osteotomy and Lapidus tarsometatarsal arthrodesis are procedures of choice in these scenarios. We have combined these 2 procedures into one called Lapicotton. The purpose of this study was to present the short-term outcomes of this technique.We hypothesized that Lapicotton will improve both clinical and radiological outcomes. Methods: We performed an IRB-approved retrospective study comprising 3 PCFDs having benefited from a Lapicotton procedure. Clinical outcomes were assessed with the European Foot and Ankle Society Score (EFAS), the Foot Function Index Score (FFI) and the Pain Catastrophizing Scale (PCS). Radiographic outcomes were assessed using weight-bearing computed tomography (WBCT) assessments. Middle Cuneiform Floor distance, Forefoot Arch Angle, Middle Facet uncoverage percentage, Talonavicular Coverage angle and the Foot and Ankle Offset (FAO) were measured. All these data were both preoperatively and postoperatively collected. Comparison between preoperative and postoperative results were done as described below. The Kruskal-Wallis H-test for independent groups was used to compare median values of the EFAS. The Wilcoxon signed-rank test for paired samples was used to compare preoperative and postoperative variables of FFI and PCS. For the radiographic measurements, normality was assessed using Shapiro-Wilk test. Comparisons were made using Student tests for normal variables and Mann-Whitney for non-normals. Results: This small series included 2 female and 1 male, with a mean age of 56 and a mean BMI of 31.8 kg/m2. Mean follow up was 2.9+/-0.2 (range from 2.7 to 3.1) months. 2 out of 3 patients simultaneously benefited of a Medial Calcaneal Displacement Osteotomy (MDCO 10mm) and a Lateral Column Lengthening (LCL 8mm). The wedge sizes used for the Lapicotton were 8 mm in all cases. Regarding clinical outcomes, EFAS (p=0.79) and FFI (p=0.99) did not showed any significant improvement whereas PCS were significantly improved (Δ=-5.67[-9.2–2.2];p=0.03). Regarding radiological outcomes, fusion was present in all the cases at the maximal follow-up. Middle cuneiform floor distance and Forefoot Arch Angle were significantly increase (respectively Δ=6.9;CI95%=[6.4;7.4];p< 0.01 and Δ=7.5;CI95%=[4.3;10.8]p<0.05). Middle Facet uncoverage was significantly improved (Δ=- 28.8;CI95%=[-33.1;-24.5]p< 0.01). Statistical power of the serie did not allowed comparison regarding the Talonavicular Coverage Angle (Δ=-14;CI95%=[-24;-3.9]) and the FAO (Δ=-3.9;CI95%=[-10.7;2.9]). Conclusion: The Lapicotton procedure showed encouraging outcomes with fusion in all cases at 3 months postoperatively, improvement in pain, correction of forefoot varus and of the of the Peritalar subluxation represented by the Middle Facet Uncoverage. These results should be moderate because other procedures (MDCO and LCL) were performed in 2/3 of the patients, and the outcomes were issued from a small cohort with short-term follow-up. Longer follow-up and a larger cohort are needed to confirm these results.