Background: There has been limited acceptance
of shoulder ultrasonography by orthopaedic surgeons in the United
States. The purpose of this retrospective study was to determine
the diagnostic performance of high-resolution ultrasonography compared
with arthroscopic examination for the detection and characterization
of rotator cuff tears.
Methods: One hundred consecutive shoulders in
ninety-eight patients with shoulder pain who had undergone preoperative
ultrasonography and subsequent arthroscopy were identified. The arthroscopic
diagnosis was a full-thickness rotator cuff tear in sixty-five shoulders,
a partial-thickness tear in fifteen, rotator cuff tendinitis in
twelve, frozen shoulder in four, arthrosis of the acromioclavicular
joint in two, and a superior labral tear and calcific bursitis in
one shoulder each. All ultrasonographic reports were reviewed for
the presence or absence of a rotator cuff tear and a biceps tendon
rupture or dislocation. All arthroscopic examinations were performed
according to a standardized operative procedure. The size and extent of
the tear and the status of the biceps tendon were recorded for all
shoulders. The findings on ultrasonography and arthroscopy then
were compared for each parameter.
Results: Ultrasonography correctly identified
all sixty-five full-thickness rotator cuff tears (a sensitivity
of 100 percent). There were seventeen true-negative and three false-positive
ultrasonograms (a specificity of 85 percent). The overall accuracy
was 96 percent. The size of the tear on transverse measurement was
correctly predicted in 86 percent of the shoulders with a full-thickness
tear. Ultrasonography detected a tear in ten of fifteen shoulders
with a partial-thickness tear that was diagnosed on arthroscopy.
Five of six dislocations and seven of eleven ruptures of the biceps
tendon were identified correctly.
Conclusions: Ultrasonography was highly accurate
for detecting full-thickness rotator cuff tears, characterizing their
extent, and visualizing dislocations of the biceps tendon. It was
less sensitive for detecting partial-thickness rotator cuff tears
and ruptures of the biceps tendon.