According to a pilot study published in ARRS ‘ American Journal of Roentgenology (AJR), the external rotational view of the flexed elbow valgus (FEVER) may improve MRI assessment of the ulnar collateral ligament (UCL) in Major League Baseball (MLB) pitchers.
“The increased joint space width confirms elbow valgus stress with FEVER view,” wrote correspondent author Thomas Knoblauch of the University of Nevada in Las Vegas. “Confidence in the diagnosis increased and additional UCLs were identified as abnormal. “
Due to the extreme repetitive valgus stress during overhead throwing maneuvers, UCL injuries remain common in throwing athletes. Since the standard positioning for MRI of the elbow is often suboptimal for rendering UCL, Knoblauch, Arizona Diamondbacks chief medical officer Gary Waslewski, and his colleagues piloted their study to assess the impact of FEVER sight on measurement of ulnotrochlear (UT) joint space and evaluation of the UCL reader, as incorporated with MRI of the elbow.
A total of 44 MLB launchers underwent MRI of the elbow, comprising both standard sequences and a density-weighted coronal sequence of fat-saturated protons in the FEVER view using specific positioning maneuvers and sandbags to immobilize the body. elbow in valgus, while visualizing the UCL parallel to its long axis. To measure UT joint space and assess confidence in UCL-related results with overall UCL normality, two radiologists independently assessed the standard and FEVER views.
“Among 44 MLB pitchers undergoing an MRI of the elbow”, Knoblauch et al. continued, “The FEVER view, compared to the standard view, gave an increase in the width of the UT joint space (mean increase, 1.80 mm) and increased confidence for three of the five results related to the UCL (mean increase, -0.14 to 0.98). ” Readers 1 and 2 rated 3 and 2 additional UCLs as abnormal on FEVER compared to the standard view; no reader classified a UCL as abnormal in standard view but normal in FEVER view.
“The results support FEVER’s view as a practical addition to standard elbow MRI protocols for achieving elbow valgus stress in throwing athletes,” concluded the authors of this AJR article, “thus providing insight functional to complement the high resolution anatomical assessment provided by MRI. “