SLR - December 2015 - Yitzchak Cohen

Title: Does Ankle Aspiration for Acute Ankle Fractures Result in Pain Relief? A Prospective Randomized Double-Blinded Placebo Controlled Trial

Reference: Ewald TJ, Holte P, Cass JR, Cross WW 3rd, Sems SA. Does Ankle Aspiration for Acute Ankle Fractures Result in Pain Relief? A Prospective Randomized Double-Blinded Placebo Controlled Trial. J Orthop Trauma. 2015 Sep; 29 (9):399–403.

Scientific Literature Review

Reviewed By: Yitzchak Cohen, DPM
Residency Program: New York Presbyterian Queens, Queens NY

Podiatric Relevance: Ankle fractures are common across varying age groups and account for as much as 9 percent of all fractures according to some studies. The relationship between fracture hematoma, hemarthrosis, soft tissue swelling and pain is not completely understood in ankle fractures. Theoretically aspiration of hematoma in acute fractures should reduce soft tissue distention, pressure, and pain. This has been shown to be effective in acute fractures elsewhere in the body most notably of the femoral neck and radial head.  Reduction in pain and swelling has been shown to reduce healing time, increase patient compliance, and improve overall outcomes. The authors of this paper hypothesized that aspiration after acute ankle fracture would decrease pain and the need for opioid pain medications.

Methods: Study design consisted of a prospective randomized, controlled, double blinded study of 124 skeletally mature patients with acute ankle fractures who met inclusion criteria (isolated, closed, OTS classification 44 injury who presented to ED within 24 hours). These patients were seen in the emergency department between October 2011 and January 2014. Patients were divided in two groups randomly using a computer program from the Mayo clinic department of Biostatistics, one group received aspiration, and the other a sham procedure. The aspiration was performed by inserting a .22 gauge needle into the ankle joint and evacuating whatever hemarthrosis was present. The sham procedure was performed by inserting the needle into the fascia but not into the ankle joint with no aspiration actually performed. All procedures were performed by an orthopedic surgery resident. The patient was blinded by using a towel or screen to obscure the patient’s view. The attending physician responsible for developing a treatment plan was also blinded to the randomization result. Primary outcomes were pain, which was measured on a numeric rating scale (NRS) from 0-10, and opioid pain medicine use in Oral Morphine Equivalents (OME’s). The pain measurements were recorded on presentation, before discharge from the ED, and every eight hours for the first three days or until surgery. Secondary outcomes were also measured.

Results: There was no statistically significant difference between the two groups in pain score at any point in time for the first 72 hours after presentation to the ED. The pain score upon arrival in the ED was 6.5 in the aspiration group and 5.9 in the control group (P =0.28). The pain score upon dismissal was 3.7 in the aspiration group and 3.4 in the control group (P=0.40). The mean reduction in pain between arrival and dismissal was 2.8 and 2.5 for the aspiration and control groups respectively (0.56). There continued to be no significant difference in pain score for the remainder of the first 72 hours or until surgery. The difference in opioid requirement was likewise not statistically significant between the two groups on the first three days post injury. On day one, the aspiration group’s mean daily OME in milligrams was 31.8 vs. 30.3 for the sham group. Day two results were 25.2 OME’s for aspiration vs. 31.4 for Sham procedure. Day three results were 20.1 OME’s for aspiration vs. 30.8 for the sham group. The secondary outcomes which included six month functional outcome scores and limb volume were also not found to be statistically significant.

Conclusion: Although aspiration has been shown to decrease pain and improve function in femoral neck and radial head fractures, it does not provide pain relief or short term functional improvement when used to treat acute ankle fractures. Femoral neck and radial head fractures where the desired outcome was achieved are both completely intracapsular which differs from ankle fractures in which the capsule is functionally disrupted as part of the injury. This allows some extravasation of the hematoma which would reduce the ability to completely aspirate the entire hematoma. Additionally the study design did not include any injection of local anesthesia which was a part of previous related studies, and therefore by not including it this helped to isolate hematoma evacuation as the lone variable being studied. In conclusion, even though this was not a very large study the authors believe that due to the strong study design, the study question was answered and therefore aspiration without local anesthetic injection for acute ankle fractures provides no clinical benefit. 

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