Relative Ratio of Coracohumeral Distance is Greater in Patients with Subcoracoid Impingement (SCI)

Jae-Chan Shim and Suk-Hwan Jang*

Relative Ratio of Coracohumeral Distance is Greater in Patients with Subcoracoid Impingement (SCI).

Subcoracoid impingement is known to be caused by the narrow space between the coracoid and the lesser
tuberosity which in turn causes impingement of the subscapularis and the biceps tendon with movements
requiring forward flexion, internal rotation, and horizontal adduction. It has been
recognized as an etiology of anterior shoulder pain for over a century.

Many studies addressed the topic and have emphasized SCI to be relatively common, yet often
unrecognized and underreported. An accurate diagnosis is critical for selecting an effective
treatment among a wide range of options starting from conservative management to open and
arthroscopic coracoplasty.

Plain radiography, computed tomography, and magnetic resonance imaging have been
used to evaluate coracohumeral distance. However, standard CT and MRI allow only static evaluation of the
subcoracoid space and are not practical for bilateral evaluation.

Diagnostic ultrasound is a well-established tool for the evaluation of rotator cuff condition and
guiding therapeutic injections. We report the use of ultrasound and MRI to measure CHD in patients with SCI
with the hypothesis that patients with SCI will have narrower CHD.

A total of 373 patients who were diagnosed with impingement syndrome clinically and radiographically at an outpatient clinic at a single institute between May 2014 and Feburary 2015 were identified.

The inclusion criteria were the symptom duration of more than 3 months, no
abnormalities on plain radiography, no rotator cuff tear on MRI, normal
contralateral shoulder, and compliance and willingness to undergo all required sonography and tests.

The exclusion criteria were stiffness or instability of the shoulder, previous surgery, and
inflammatory condition of shoulder including infection or
calcific tendinitis.

Radiol Open J. 2017; 2(2): 26-31. doi: 10.17140/ROJ-2-115