The Effectiveness of Saline Load Test in Detecting Simulated Traumatic Elbow Arthrotomies: A Cadaveric Investigation

Background The saline load test has not been well explored in the elbow. We aimed to determine 1) the saline infusion volume needed for 90%, 95%, and 99% sensitivity in detecting elbow arthrotomy; and 2) factors associated with higher volume at detection using sixteen forequarter upper extremity amputation cadavers. Methods Sixteen fresh-frozen forequarter upper extremity amputations were procured, and demographic data, including age, body mass index (BMI), and laterality, were recorded. The olecranon process, radial head, and the lateral epicondyle were palpated, and elbow arthrotomy was consistently performed at the direct lateral arthroscopic portal site. The elbow joint was loaded with saline mixed with methylene blue (concentration: 2 mg/300 mL) using an 18-gauge needle inserted just medial to the triceps tendon 2 cm superior to the olecranon. Results Mean volume for extravasation was 12.2 mL ±6.26. Volume needed for 90%, 95%, and 99% sensitivities were 21 mL, 23 mL, and 25.4 mL. Linear regression demonstrated that increasing age was associated with lower volume to extravasation (OR: 0.67; 95% CI: 0.48-0.932; p=0.037), while BMI (p=0.571) and extremity laterality (p=0.747) did not affect the volume. Conclusions The saline load test can be effective in diagnosing the violation of the elbow joint in traumatic injuries. This test should be used in conjunction with the clinical examination and radiographs before operative decisions are made. We recommend using ≥26 mL to rule out traumatic elbow arthrotomy.