Abstract
Category:
Ankle; Trauma
Introduction/Purpose:
Flexible syndesmotic devices have been associated with a reduction in hardware complications, syndesmotic diastasis, and rehabilitation time. Current guidelines suggest syndesmotic devices should be placed specifically 1.5-3.0 cm above the tibiotalar joint, however some may argue that this precise guideline is not necessary. In many syndesmotic injuries, a fibula fracture can occur at this landmark, which may increase the risk of fracture displacement and entrapment of the non-absorbable suture within the fracture itself. The goal of placing a flexible syndesmotic device is to help the fibula “find its home” in the incisura. Therefore, specific proximity to the tibial plafond may be negligible. The current study compared outcomes, union rate, and complications associated with flexible syndesmotic device placement at varied distances from the tibial plafond.
Methods:
Flexible syndesmotic devices, were placed in patients with a confirmed fracture-associated syndesmotic injury on CT scan. Cases were retrospectively analyzed at a minimum one-year follow-up. 24 patients met our inclusion criteria for this study. 14/24 devices were placed between 1.5-3.0 cm from the tibial plafond (mean 2.26±0.35cm), while the other 10/24 were placed outside of this guideline (mean 4.30±0.64cm). On postoperative radiographs, the placement of each syndesmotic device was measured as a proximal distance from the tibial plafond. Cases were placed into cohorts, defined by device placement within or outside of the 1.5-3.0 cm guideline. Incidences of postoperative complication, revision surgery, radiographic nonunion, and hardware failure were recorded. Patient Reported Outcome Measurement System (PROMIS) pain, function, and mobility scores were recorded. Outcome measures of each study cohort were compared by t-test. Categorical data was compared by Chi-squared analysis.
Results:
Flexible syndesmotic device placement within current guidelines demonstrated improvement in PROMIS function (p=0.044), pain (p=0.032), and mobility (p=0.035) scores at postoperative follow-up. Similarly, device placement outside of the 1.5-3.0 cm guidelines demonstrated improvement in PROMIS function (p=0.010), pain (p=0.026), and mobility (p< 0.001) scores. There was one patient with a flexible syndesmotic device placed at 1.5-3.0 cm who experienced a traumatic break and wound infection secondary to noncompliance with non-weightbearing status. This patient required debridement, hardware removal, and eventually a below knee amputation. Amongst cases with devices placed outside current guidelines, there was one case of painful hardware, requiring removal (10.00%). There was no statistical difference noted in PROMIS pain scores or complications between the two cohorts.
Conclusion:
Current guidelines suggest the placement of flexible syndesmotic devices should be limited to 1.5-3.0 cm proximal to the tibiotalar joint. However, these guidelines may be outdated. The current study presents novel evidence that alternative placement of syndesmotic devices may lead to improvement in patient reported function, pain, and mobility, with a low complication rate. There was no evidence of nonunion in any patient in the current study; all cases maintained their syndesmotic reduction. This study may serve to better inform the scope of flexible syndesmotic device application in cases of ankle fractures requiring fixation of the syndesmosis.
