SLR - May 2013 - Ashley Mayer
Reference: Mendelsohn ES, Hoshino CM, Harris TG, Zinar DM. J Orthop Trauma. 2013 April; 27(4): 201-206.
Scientific Literature Review
Reviewed by: Ashley Mayer, DPM
Residency Program: Temple University Hospital, Philadelphia, PA
Podiatric Relevance: Ankle fractures are among the most common injuries seen by foot and ankle surgeons. Additionally, obesity has reached epidemic proportions in the United States with a prevalence of approximately 30 percent in most sex and age groups. Obesity has been linked to a higher incidence of complications in various orthopaedic procedures, but a correlation has not been readily studied for ankle fractures. The authors attempted to evaluate the influence of obesity on postoperative loss of syndesmotic reduction for rotational ankle injuries.
Methods: From September 2007 to December 2010, the authors retrospectively reviewed charts and x-rays of consecutive patients with operative management of syndesmotic injuries. Only injuries that were considered unstable were treated surgically. After stabilization of the malleoli, either the Cotton hook test or external rotation stress test under fluoroscopy was performed, and a positive test dictated syndesmotic fixation. A number of different constructs were used, including 3.5 or 4.5mm screws with either three or four cortices. Postoperatively, patients were casted for four to six weeks. At that point, they began physical therapy with range of motion but were maintained NWB for eight weeks total.
Results: Two hundred thirteen patients with operatively treated syndesmotic injuries were separated into obese and non-obese groups. The average BMI of the obese cohort was 37, while the average BMI of the non-obese group was 26. Rates of failure significantly differed between the two groups with the obese group failing 15 percent and the non-obese group failing 1.8 percent. The presence of diabetes, smoking status and type of construct used were not associated with loss of reduction.
Conclusions: In the current study, the authors found obesity to be the single strongest predictor of failure of syndesmotic fixation, and obese patients were 12 times as likely to suffer a postoperative loss of reduction compared to non-obese patients. In order to minimize complications in this “at risk” cohort, stronger mechanical constructs, such as addition of Ilizarov frame or simply use of 4.5mm screws, have been recommended. Additionally, prolonged immobilization and non-weight-bearing have also been recommended in obese patients. The authors have identified that obesity is linked to an increased rate of complications following surgical management of syndesmotic injuries, and this is especially important because surgical and postoperative management may need to be altered in this subgroup of patients in order to produce good outcomes.