Efficacy of Multimodal Analgesic Injections in Operatively Treated Ankle Fractures: A Randomized Controlled Trial

SLR - February 2020 - James Willmore

Reference: Hancock KJ, Rice OM, Anthony CA, Glass N, Hogue M, Karam M, Marsh L, Willey MC. Efficacy of Multimodal Analgesic Injections in Operatively Treated Ankle Fractures: A Randomized Controlled Trial J Bone Joint Surg Am. 2019 Dec 18;101(24):2194-2202. doi: 10.2106/JBJS.19.00293.

Scientific Literature Review

Reviewed By: James Willmore, DPM
Residency Program: Scripps Mercy Kaiser Hospital – San Diego, CA

Podiatric Relevance: Pain after ankle fractures is common and prescribing opioids has been the de facto treatment option. With the current opioid crisis physicians are looking for alternative methods to achieve pain reduction after surgery and decrease the need for prescription opioids. Only one high level study has evaluated the use of anesthetic based injections in rotational ankle fractures to this point. Post-operative anesthetic injections have very little side effects compared to opioids. This study seeks to evaluate the effectiveness of a multimodal surgical site injection on post-operative pain control after surgically treated rotational ankle fractures.

Methods: One hundred patients were included in the study. The surgery was performed by one of four orthopedic trauma surgeons. Exclusion criteria were open fractures, patient incarceration, age of <18 years, lower extremity neuropathy, revision procedures, other concurrent injuries, study medication allergies, encephalopathy or inability to communicate pain level, necessity for regional anesthesia or refusal to participate. The study was a prospective, double blinded, randomized control trial with two parallel arms. The patients were randomized through a random number generation into a treatment and control group. After surgery the patient received a 25 mL multimodal injection consisting of 20 mL 1 percent ropivacaine, 0.6 mL of epinephrine, 1 mL of Morphine 5mg/mL solution, and 3.4 mL of 0.9 percent saline solution. Post-operative pain management consisted of oral hydromorphone, IV dilaudid and could be escalated if inadequate pain control was noted. The primary outcomes include: VAS pain score pre-operatively and immediate post-operative, then every four hours afterwards. Secondary measures included: opioids consumption, length of stay, discharge destination and adverse effects.

Results: There was a statistically significant decrease of pain at 24 hours (P=0.01) and 48 hours (P<0.01). When compared over time there was no statistical significance between pain in the treatment and control groups. There was no difference in the number of opioids used between the two groups. There was no difference in the length of stay between the two groups.  

Conclusions: This is the second study about local anesthetic based injections for rotational ankle fractures. The other study used liposomal Marcaine and showed reduction of pain up to three days in the intervention group. This study used ropivacaine primarily and showed only a small decrease in pain at 24 and 48 hours.  Neither study showed a decrease in opioid use. In conclusion, this study showed a very minimal decrease in pain within 48 hours of the surgery but no decrease in opioid use, or length of stay in the hospital.