Plate Alone Versus Plate and Lag Screw for Lapidus Arthrodesis: A Biomechanical Comparison of Compression
Department of Orthopedics and Physical Rehabilitation
BACKGROUND: Arthrodesis of the first tarsal metatarsal joint can be accomplished in many ways. The compressive force attained between various constructs remains unclear. This study compares compression achieved through a locking/compression Lapidus plate both with and without the addition of a lag screw.
METHODS: A dorsal medial Lapidus/locking compression plate (Total Compression Plate System, OrthoPro, Salt Lake City, UT, now Wright Medical) was applied to one cadaveric limb, while the same plate with the addition of a 4.0-mm cannulated lag screw was applied to the contralateral limb for a total of 5 matched pairs of cadaveric specimens. Compressive force was recorded over time and compared between the constructs using a compression sensor (8" FlexiForce Resistive Force Sensor, Phidgets Inc, Calgary, Alberta, Canada).
RESULTS: Compression was maintained for 45.4 minutes in the plate only construct, and 317 minutes with the addition of the lag screw ( P = .010). The mean time to 50% peak compression for the plate only construct was 4.90 minutes compared with 15.11 minutes for plate with lag screw construct (P = .012).
CONCLUSION: The addition of a lag screw is recommended for extending the length of compression and possibly reducing nonweightbearing time and the risk of nonunion.
LEVELS OF EVIDENCE: Level V.
compression plate, tarsometatarsal joint, Lapidus arthrodesis, midfoot fusion
DOI of Published Version
Foot Ankle Spec. 2018 Feb 1:1938640018758374. doi: 10.1177/1938640018758374. Link to article on publisher's site
Foot and ankle specialist
Garas PK, DiSegna S, Patel AR. (2018). Plate Alone Versus Plate and Lag Screw for Lapidus Arthrodesis: A Biomechanical Comparison of Compression. Orthopedics and Physical Rehabilitation Publications and Presentations. https://doi.org/10.1177/1938640018758374. Retrieved from https://escholarship.umassmed.edu/ortho_pp/198