MR imaging of patients with lateral epicondylitis of the elbow: is the common extensor tendon an isolated lesion?

Abstract

Objective: To investigate whether an injury of the common extensor tendon (CET) is associated with other abnormalities in the elbow joint and find the potential relationships between these imaging features by using a high-resolution magnetic resonance imaging (MRI).

Methods: Twenty-three patients were examined with 3.0 T MR. Two reviewers were recruited for MR images evaluation. Image features were recorded in terms of (1) the injury degree of CET; (2) associated injuries in the elbow joint. Spearman's rank correlation analysis was performed to analyze the relationships between the injury degree of CET and associated abnormalities of the elbow joint, correlations were considered significant at p<0.05.

Results: Total 24 elbows in 23 patients were included. Various degrees of injuries were found in total 24 CETs (10 mild, 7 moderate and 7 severe). Associated abnormalities were detected in accompaniments of the elbow joints including ligaments, tendons, saccussynovialis and muscles. A significantly positive correlation (r = 0.877,p<0.01) was found in injuries of CET and lateral ulnar collateral ligament (LUCL).

Conclusion: Injury of the CET is not an isolated lesion for lateral picondylitis, which is mostly accompanied with other abnormalities, of which the LUCL injury is the most commonly seen in lateral epicondylitis, and there is a positive correlation between the injury degree in CET and LUCL.

Figure 1. A 36-year-old female with left elbow pain about 1 month.

(A,B) Coronal fat-suppressed FSE T2-weighted image shows abnormal fluid signal intensity affecting about 50% of the CET thickness (white arrow), demonstrating moderate injury. (C) Coronal fat-suppressed FSE T2-weighted image shows thickening and abnormal mildly increased signal intensity within the LUCL origin (white arrow), which suggests mild injury. (D) Coronal fat-suppressed FSE T2WI shows thickening and mildly increase signal intensity within the RCL (white arrow), demonstrating mild injury. Intramuscular edema shows as high-signal-intensity focus is seen within the extensor carpi muscle (white curve arrow ). (E) Coronal fat-suppressed FSE T2-weithted image shows mildly increased signal intensity within the proximal MCL (white arrow), a finding suggestive of mild injury.

Figure 2. A 40-year-old female with right elbow pain about 3 months.

(A,B) Coronal and Saggital fat–suppressed FSE T2-weighted image shows abnormal fluid signal intensity affecting more than 80% of the CET thickness, which suggests severe injury (white arrow). (C) Coronal fat-suppressed FSE T2-weighted image shows thinning and line-like high signal intensity across the LCUL origin, a finding suggestive of severe injury (white arrow). (D) Coronal fat-suppressed FSE T2-weithted image shows complete absence of the proximal fibers of the RCL (black arrow). demonstrating full-thickness tear of the RCL (white arrow). (E) Axial fat-suppressed FSE T2-weighted image shows joint effusion (white arrow).