Comparison of Standard Screw Fixation Versus Suture Button Fixation in Lisfranc Ligament Injuries

SLR - January 2011 - Sophia Barnett

Reference:  Ahmed, S., Bolt, B., McBryde, A. (2010). Comparison of standard screw fixation versus suture button fixation in lisfranc ligament injuries. Foot and Ankle International, 31,892-896.

Scientific Literature Reviews

Reviewed by: Sophia Barnett, DPM
Residency Program: Botsford Hospital Podiatric Medicine and Surgical Residency

Podiatric Relevance:
This article provides valuable information for the treatment of Lisfranc ligament injuries by comparing two common fixation techniques.

Methods:
Eight fresh-frozen, matched paired cadavers with an average age of 50 years of age were tested. Load to failure was performed upon the entire foot and ankle complex which was mounted in a plantigrade position on an 858 MTS Bionix material testing machine.  A compressive load of 600 N was applied to the tibia/fibula complex over a period of 10 seconds. A baseline distance between the base of the first metatarsal at the metaphyseal flare and the corresponding perpendicular point on the base of the second metatarsal was measured. Measurement was made (1) prior to loading, (2) after loading a 600-N load to the intact specimen, and then (3) after surgical division of the dorsal and plantar Lisfranc ligament was performed. Diastasis was then measured. Each specimen underwent randomized fixation with either interfragmentary screw fixation from the medial cuneiform to the base of the second metatarsal with a 4.0 cannulated, partially threaded screw without washer (Depuy, Warsaw, IN) or with a mini tight rope (Arthrex, Naples, FL) in the same fashion. In the suture button group, the suture button was tied with four knots. Diastasis measurement was again taken at the previously marked points. Each specimen underwent a load to failure test at a rate of 50 mm per minute.

Results: 
When comparing the fixed and intact loaded measurements for each device, results showed that the screw had an average diastasis of -0.1 mm (±0.5 mm), and the suture button had an average diastasis of 1.1 mm (±0.4 mm), which was statistically significantly different (p < 0.00). Results for the fixed loaded and the fixed unloaded measurements showed the screw (-0.2 ± 0.1 mm) had a significantly (p = 0.001) lower amount of diastasis than the suture button (-1.2 ± 0.5 mm). There was no statistically significant difference (p = 0.21) between the screw and the suture button when the specimens were loaded to failure secondary to slippage, and other structures in the foot and ankle complex .

Conclusions:
Standard interfragmentary screw fixation with a 4.0 cannulated screw had less displacement than the Arthrex Mini Tightrope in isolated Lisfranc ligament injuries. As such, open reduction and screw fixation of these injuries should continue to be the accepted treatment.