First tarsometatarsal fusion using saw preparation vs. standard preparation of the joint: A cadaver study

Nicholas Dahlgren; John L Johnson; Samuel Huntley; Haley McKissack; Karthikeyan Chinnakkannu; Sameer Naranje; Ashish Shah

doi:10.1016/j.fas.2019.08.016

First tarsometatarsal fusion using saw preparation vs. standard preparation of the joint: A cadaver study

Foot Ankle Surg. 2020 Aug;26(6):703-707. doi: 10.1016/j.fas.2019.08.016. Epub 2019 Sep 13.

Authors

Nicholas Dahlgren¹, John L Johnson¹, Samuel Huntley¹, Haley McKissack¹, Karthikeyan Chinnakkannu¹, Sameer Naranje¹, Ashish Shah²

Affiliations

¹ Department of Orthopaedic Surgery, University of Alabama, 1313 13th Street South, Birmingham, AL 35205, USA.
² Department of Orthopaedic Surgery, University of Alabama, 1313 13th Street South, Birmingham, AL 35205, USA. Electronic address: ashishshah@uabmc.edu.

PMID: 31548149
DOI: 10.1016/j.fas.2019.08.016

Abstract

Background: First tarsometatarsal (TMT) joint fusion is effective for treatment of arthritis and some first ray deformities. To prepare the articular surfaces, cartilage should be carefully but completely denuded. Inadequate preparation may result in non-union, while excessive preparation may cause ray shortening and consequential transfer metatarsalgia. Preparation can be performed with an osteotome or a saw. The purpose of this study was to investigate whether utilization of an osteotome or saw would minimize shortening of the first ray in TMT arthrodesis.

Methods: Ten fresh-frozen cadaver specimens were randomly assigned to undergo joint preparation using either an osteotome (n=5) or saw (n=5). Sample size was determined by cadaver availability. Fusion was performed using a cross-screw construct through the dorsal aspect of the proximal phalanx and the medial cuneiform. Pre- and post-operative X-rays were taken with a radiopaque ruler in the field, and changes in length in the first metatarsal and first cuneiform were compared between osteotome and sawblade groups.

Results: The average change in metatarsal length was significantly smaller in the osteotome group (1.6mm) as compared to the saw group (4.4mm) (p=0.031). The average percent change in metatarsal length was also significantly smaller in the osteotome group (3.0%) compared to the saw group (8.4%) (p=0.025). There was no significant difference between the two groups with respect to change in cuneiform length. The osteotome group demonstrated a significantly smaller average measured change (3.0mm vs. 6.9mm, p=0.001) and percent change (4.1% vs. 9.3%, p<0.001) in total length (cuneiform plus metatarsal) in comparison to the saw group.

Conclusions: In first TMT fusion, joint preparation with an osteotome may prevent over-shortening of the first ray in comparison to preparation with a saw.

Keywords: Arthrodesis; Joint preparation; Lapidus; Orthopedics; Osteotome; Tarsometatarsal fusion; Tarsometatarsal joint.

MeSH terms

Aged
Arthrodesis / instrumentation*
Cadaver
Female
Foot Joints / surgery*
Humans
Male
Metatarsal Bones / surgery*
Random Allocation
Tarsal Bones / surgery*