2024 FSA Podium and Poster Abstracts

S006: THE DEVIL IS IN THE DETAILS: DO PERIPHERAL NERVE BLOCKS MASK OR DELAY THE DIAGNOSIS OF ACUTE COMPARTMENT SYNDROME IN TIBIAL PLATEAU FRACTURES? A RETROSPECTIVE REVIEW
Meena Kanhai, MD; Dimitrios Kampouris, MD; Nathaniel Smith; Meera Sundar, BS; Richa Wardhan, MD, FASA; University of Florida

The tibial plateau is a major weight bearing surface within the most kinematically complex joint in the human body. Fracture of the plateau is associated with other complications including ligamentous injuries, neurovascular injuries, and compartment syndrome. Incidence of acute compartment syndrome (ACS) varies from 7-20% and depends on risk factors (Schatzker type IV, high energy mechanism, associated fibula fracture, fracture length, associated plateau-shaft injury). It is a common practice in many institutions to avoid nerve blocks in these patients to avoid masking symptoms of ACS which then could delay diagnosis and treatment. The purpose of this preliminary retrospective review is to determine if peripheral nerve blocks delay the diagnosis of ACS in patients with tibial plateau fractures.  

After obtaining approval from the University of Florida Institutional Review Board (IRB # 202102875), which waived the requirement for written informed consent, we obtained records of patients that presented from January 2015 to December 2019 with tibial plateau fractures using the Integrated Data Repository (IDR). This generated a list of 1267 patients, with 721 charts reviewed to date. We reviewed patient information including age, sex, Schatzker type of plateau fracture, mechanism of injury, type of surgery, and nerve block received. 

We found 252 tibial fractures (proximal or diaphyseal), comprising individuals with an average age of 49.1 years (18 to 80 years). There were 32 patients in high risk Schatzker type IV, V, and VI category. All reviewed patients received continuous femoral and sciatic catheters. We used lower concentration of local anesthetic ropivacaine 0.2% both for bolus and continuous infusion. So far in our preliminary review, we did notencounter any patients who developed ACS within all categories of tibial plateau fracture subtypes including high risk. 

At University of Florida, we place perineural catheters (femoral and gluteal sciatic catheters) or single injection nerve blocks (femoral and popliteal/sciatic) routinely for a majority of tibial fractures, both external and internal fixations, per discretion of the trauma orthopedic surgeons. As suggested by literature, clinical evaluation or symptoms alone are not reliable or safe to accurately assess ACS, “Only pain out of proportion to the injury and pain on passive stretch are helpful in the diagnosis.”  Therefore, we beg the question do peripheral nerve blocks inhibit the pain out of proportion associated with the diagnosis of ACS? Dwyer et al suggests that peripheral nerve blocks should be avoided for all tibial diaphyseal and all high-risk plateau fractures. However, we speculate that nerve blocks may not increase or mask symptoms of compartment syndrome in a patient group that experiences excruciating pain, post trauma. Stratifying fractures into risk categories may be the key to advocate for or against nerve blocks. 

To our knowledge, this study is the only retrospective study that attempts to stratify tibial fractures and judge incidence of compartment syndrome in patients who received peripheral nerve blocks. Our current literature and patient review has not proven evidence of such to support that placing peripheral nerve blocks is contraindicated due to the possibility of delaying the diagnosis of ACS.