Evaluating midcalcaneal length after Evans calcaneal osteotomy: a comparison of the locking plate and tricortical allograft wedge

Transcription

1 IFFAS AOFAS Chicago, 2014 Evaluating midcalcaneal length after Evans calcaneal osteotomy: a comparison of the locking plate and tricortical allograft wedge Garrett M. Wobst, DPM, AACFAS, Nicole M. Protzman, BS, MS, Raymond E. McCarroll, DPM, FACFAS, Stephen A. Brigido, DPM, FACFAS

2 IFFAS AOFAS Chicago, 2014 Evaluating midcalcaneal length after Evans calcaneal osteotomy: a comparison of the locking plate and tricortical allograft wedge Garrett M. Wobst My disclosure is in the final AOFAS mobile app. I have no potential conflicts with this presentation.

3 INTRODUCTION Evans calcaneal osteotomy remains a cornerstone in the correction of the flexible flatfoot (1-5) Through lengthening of the lateral column, tri-planar correction is consistently achieved (6,7) Image source:

4 INTRODUCTION Many methods have been employed to maintain the length of the lateral column (8) Tricortical autograft and allograft wedges Trabecular metal wedges Locking and non-locking plates Simple screw fixation Figure from Butterworth, 2013 (9)

5 INTRODUCTION Compared with a tricortical graft, the locking plate has been shown to better preserve lateral column length (10) Recently, a procedure-specific wedge locking plate was designed to maintain the mid-calcaneal length following Evans osteotomy Image source:

6 PURPOSE To compare the maintenance of mid-calcaneal length after Evans calcaneal osteotomy when either a low profile wedge locking plate or a tricortical allograft wedge was employed HYPOTHESIS The wedge locking plate would better maintain mid-calcaneal length compared with the tricortical allograft wedge

7 Materials & Methods Retrospective chart review (September 2009 June 2013) Inclusion Criteria Presented with a reducible, flexible, symptomatic flatfoot Exhausted conservative treatment Elected to undergo surgical correction of the deformity Evans calcaneal osteotomy was performed Either a wedge locking plate or a tricortical allograft wedge was employed to maintain postoperative mid-calcaneal length Minimum radiographic follow-up of 6 months Exclusion Criteria Underwent an adjunctive hindfoot, bony procedure at the time of osteotomy

8 Materials & Methods Mid-calcaneal Length Measurements Immediate postoperative period, and again at 3 months and 6 months Distance measured from the most superior aspect of the convex arc on the posterior subtalar facet and the most inferior aspect of the concave arc on the calcaneus at the calcaneocuboid joint (10) Change in mid-calcaneal length o Immediate postoperative measurements as baseline Figure from Dayton et al (11)

9 Results Patient Demographics Demographic All Patients Tricortical Allograft Wedge Locking N = 24 Wedge Plate n = 9 n = 15 Age (yr) 48.1 ± ± ± 15.8 Body Mass Index (kg/m 2 ) 31.8 ± ± ± 5.8 Gender Female 18 (75.0) 8 (88.9) 10 (66.7) Male 6 (25.0) 1 (11.1) 5 (33.3) Data presented as mean ± standard error or count (%).

10 Results Change in Mid-calcaneal Length Data presented as mean ± standard error Δ Mid-calcaneal Length (mm) Tricortical Allograft Wedge Wedge Locking Plate Months 6 Months Time *

11 Discussion Our data indicate that the wedge locking plate better maintains midcalcaneal length compared with the tricortical allograft wedge 6 months following surgical correction Resorption of the allograft wedge at the bone graft interface may cause a decrease in mid-calcaneal length

12 REFERENCES 1. Sangeorzan BJ, Mosca V, Hansen ST Jr. Effect of calcaneal lengthening on relationships among the hindfoot, midfoot, and forefoot. Foot Ankle 14: , Guha AR, Perera AM. Calcaneal osteotomy in the treatment of adult acquired flatfoot deformity. Foot Ankle Clin 17: , Butterworth M. Maximizing the effectiveness of the Evans calcaneal osteotomy. Podiatry Today 26:20-26, DeYoe BE, Wood J. The Evans calcaneal osteotomy. Clin Podiatr Med Surg 22: , vi, Roye DP Jr, Raimondo RA. Surgical treatment of the child s and adolescent s flexible flatfoot. Clin Podiatr Med Surg 17: , vii-viii, Evans D. Calcaneo-valgus deformity. J Bone Joint Surg Br 57: , Arangio GA, Chopra V, Voloshin A, Salathe EP. A biomechanical analysis of the effect of lateral column lengthening calcaneal osteotomy on the flat foot. Clin Biomech (Bristol, Avon) 22: , Abbasian A, Zaidi R, Guha A, Goldberg A, Cullen N, Singh D. Comparison of three different fixation methods of calcaneal osteotomies. Foot Ankle Int 34: , Butterworth M. Maximizing the effectiveness of the Evans calcaneal osteotomy. Podiatry Today 26:20-26, Dayton P, Prins DB, Smith DE, Feilmeier MJ. Effectiveness of a locking plate in preserving midcalcaneal length and positional outcome after Evans calcaneal osteotomy: a retrospective pilot study. J Foot Ankle Surg 52: , Dayton P, Wienke JC Jr, Prins DB, Haulard JP, Feilmeier MJ, Wiarda C. Measurement of mid-calcaneal length on plain radiographs: reliability of a new method. Foot Ankle Spec 4: , 2011.