SLR - November 2015 - Alissa Kuizinas

In Vivo Syndesmotic Overcompression After Fixation of Ankle Fractures With a Syndesmotic Injury

Reference: Cherney SM, Haynes JA, Spraggs-Hughes AG, McAndrew CM, Ricci WM, Gardner MJ. In Vivo Syndesmotic Overcompression After Fixation of Ankle Fractures With a Syndesmotic Injury. J Orthop Trauma. 2015 Sept; 29(9):414-419.

Scientific Literature Review

Reviewed By:
Alissa Kuizinas, DPM
Residency Program: Hoboken University Medical Center

Podiatric Relevance: Ankle fractures are a common traumatic injury of the lower extremity, many of which involve concomitant tibiofibular syndesmotic injuries. Proper fixation of these syndesmotic injuries is crucial to prevent early arthrosis and functional limitations for the patient. While it is important for the surgeon to achieve sufficient fixation of the syndesmosis, there is little research exploring the frequency or consequences of overcorrection of the syndesmosis. Evaluation of the syndesmosis using standard imaging techniques has proven to be difficult and imprecise. The authors of this study utilize postoperative computed tomography of bilateral extremities to compare the affected to unaffected limb for measurement of the reduction and rotation of the tibiofibular syndesmosis following fixation. The aim of the study was to evaluate whether overcorrection or malreduction of syndesmotic injuries were more prevalent with certain injury types or if they could be a result of the type of reduction forceps used.

Methods: This study was a prospective cohort consisting of 27 patients with operative treatment of syndesmotic injuries. The ankle fractures were classified as either Weber B injuries or ‘suprasyndesmotic lesions.’ Fourteen of the patients had injury to the posterior malleolus. Each syndesmosis had been reduced intraoperatively using either a pointed reduction clamp or a ball point pelvic reduction forceps, and syndesmotic fixation was achieved with either one or two 3.5 mm transsyndesmotic quadri-cortical positional screws. The ankles of the selected patients were measured postoperatively using bilateral computed tomography, comparing the reduction of the treated ankle to the uninjured side. The primary outcome measure was differences in fibular position within the tibial incisura in relation to the type of injury, type of reduction forceps used, and presence of posterior malleolar injury. The measurements obtained were medializaton of the fibula and external rotation of the fibula.

Results: On average, the cohort was found to have significant overcompression of the syndesmosis of 1 mm, defined as fibular medialization compared to the unaffected side. A substantial number also showed an increase in external rotation of the fibula of 5 degrees. The ankles with posterior malleolar injury and suprasyndesmotic injuries had an increase in malrotation but equivalent overcompression to those without posterior malleolar injury and Weber B injuries respectively. There was no significant difference in external rotation of the fibula between the types of reduction forceps, however there was an increase in overcompression with the pelvic ball spike reduction clamp.

Conclusions: The present study demonstrates that overcorrection of ankle syndesmotic injuries are in fact a common outcome regardless of injury pattern. The results show that ankles with posterior malleolar involvement are even more likely to be overcorrected. Based on this data it is important to use caution when reducing ankle syndesmotic injuries to avoid excessive tightening and rotation of the syndesmosis. The article evokes further questions regarding the consequences of overcorrection. More research is needed to determine whether the average amount of overcorrection leads to functional consequences.  Nevertheless, the article discusses an important topic that should lead to increased mindfulness by the surgeon when correcting syndesmotic injuries. The method and type of instrumentation used for reduction may be significant, and the surgeon should be aware that overcorrection is indeed possible. The cohort included in this study was fairly small and does not include enough patients in the pointed reduction forceps group to truly compare the results of forceps used, but it is useful to consider that certain instruments may be more aggressive than others. Another consideration is the type of syndesmotic fixation used; this study included only syndesmotic screw fixation. It would be interesting to determine if other types of fixation lead to similar rates of overcorrection. 

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