Do We Really Need to Worry About Calcaneocuboid Subluxation During Lateral Column Lengthening for Planovalgus Foot Deformity?

SLR - July 2021 - Chandler J. Ligas

Reference: Siebert M, Hedrick BN, Zide JR, Thomas DM, Shivers C, Pierce WA, Kanaan Y, Harris MC, Riccio AI. Do We Really Need to Worry About Calcaneocuboid Subluxation During Lateral Column Lengthening for Planovalgus Foot Deformity? J Pediatr Orthop. 2021 Mar 1

Level of Evidence: Level V – Cadaver Study

Scientific Literature Review

Reviewed By: Chandler J. Ligas, DPM
Residency Program: Emory University School of Medicine – Decatur GA

Podiatric Relevance: The use of the Evan’s Calcaneal Osteotomy (Lateral Column Lengthening) is performed frequently by the Podiatric Surgeon for Pediatric Pes Planovalgus deformity. This article is relevant because it attempts to characterize alterations at the CC joint after lateral column lengthening (LCL) and determine if Steinmann pin stabilization of the CC joint before distraction maintains a normal relationship.

Methods: Seven matched pairs of fresh-frozen cadaveric feet had plain radiography and CT imaging performed. LCL by osteotomy through the anterior calcaneus was then performed. One Cadaver foot of each pair had a Steinmann Pin placed across the CC joint prior to LCL. The osteotomy was then performed and maintained with a 12-millimeters porous titanium wedge. Repeat imaging was obtained and compared with pre-procedure studies to quantify sagittal and rotational differences at the CC articulation. 

Results: The plain film evaluation of the Lateral Column Lengthening shows significantly significant increases in the percentage of the articular surface dorsal to the cuboid when comparing the unpinned CC joints to the pinned CC joint group. There were no such instances of complete subluxation of either group. The CT evaluation of the two groups showed statistically significant increases in the internal and external rotation of the calcaneus in relation to the cuboid. 

Conclusions: LCL through a calcaneal distraction osteotomy results in significant increases in apparent dorsal subluxation of the calcaneus seen on plain radiography and rotational subluxation of the CC joint in unpinned compared to pinned specimens. The present findings suggest that the rotational changes identified on three-dimensional imaging are interpreted as dorsal translation when viewed two dimensionally using plain lateral radiography. I believe that these conclusions are a topic of discussion however, this article had major limitations. One of those was the fact that they used adult aged cadaveric specimens that when one lengthens the lateral column will have multiple soft tissue and adult osseous structures in place which would result in subluxation/rotation of the calcaneus. A LCL when done in the flexible pes planovalgus pediatric patient would not have these soft tissue/osseous structures resulting in these rotation/subluxations. Further research on either live subjects or cadavers with pes planovalgus  deformity would help support or refute the findings of this study.