Title: Syndesmotic Instability in Weber B Ankle Fractures: A Clinical Evaluation
Authors: Stark, Erik; Tornetta III, Paul; Creevy, William R.
Source: The Journal of Orthopedic Trauma. 2007; 21:124-128
PODIATRIC RELEVANCE:
Supination-external rotation (SER) type injuries are amongst the most common ankle injuries. The purpose of this study was to evaluate syndesmotic stability in SER stage 4-Weber B fractures with respect to the current recommendations for syndesmotic fixation in unstable Weber B, SER pattern lateral malleolar fractures.
METHODS:
In a seven-year period, 238 skeletally mature patients were surgically treated for unstable SER stage 4, Weber B lateral malleolar fractures with radiographically demonstrated deltoid ligament incompetence. After ORIF of the fibular fracture, syndesmotic stability was determined by stabilizing the foot/leg and applying an external rotation force to the ankle. Syndesmotic instability was defined as any lateral talar subluxation (the relationship of the lateral edge of the talar dome to the lateral edge of the plafond) with medial joint space widening. Medial clear space was considered widened if greater than the superior clear space. If the syndesmosis was found to be unstable, a trans-syndesmotic screw was placed.
RESULTS:
Intraoperatively, 93 of 238 patients (39%) had syndesmotic instability. There was no significant difference in age and sex of Pts with/without syndesmotic injury (P < 0.05, t test). All but five patients (who were lost to follow-up) went on to a complete union of the fracture without syndesmotic instability.
COMMENTS:
Previous recommendations for syndesmotic fixation have been based largely on a single cadaveric study and a small clinical study. It was assumed that the interosseous membrane, interosseous ligament and capsular structures do not stretch prior to fracture and that the interosseous membrane is not disrupted above the level of the fracture. Based on these findings, recommendations are made to abandon general criteria for syndesmotic fixation, in favor of individual examination of the syndesmosis after ORIF of the fibula in unstable SE pattern Weber B fibular fractures. Syndesmotic instability is common after boney fixation in unstable Weber B SE pattern lateral malleolar fractures.
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Disclaimer:
Scientific Abstract Monthly postings are submitted by podiatric surgical residents. The ideas presented are not the opinions of the American College of Foot and Ankle Surgeons (ACFAS), nor are they presented as facts. ACFAS presents this information without any warranty of any kind, expressed or implied, and is not liable for its accuracy nor for any loss or damage caused by the user's reliance on information obtained in these areas.