Quantitative MRI characterization of arthroscopically verified supraspinatus pathology: comparison of tendon tears, tendinosis and asymptomatic supraspinatus tendons with T2 mapping.
OBJECTIVE
Quantitative MRI T2 mapping is a non-invasive imaging technique sensitive to biochemical changes, but no studies have evaluated T2 mapping in pathologic rotator cuff tendons. It was sought to evaluate the efficacy of T2 mapping in detecting differences in the supraspinatus tendon (SST) among patients with tendinosis, partial tears and minimally retracted full-thickness tears, relative to asymptomatic volunteers.


METHODS
The pathologic cohort consisted of two arthroscopically verified groups: tendinosis and a tear group of partial tears or minimally retracted full-thickness tears, and was compared to an asymptomatic cohort with no prior history of shoulder pathology. The SST was manually segmented from the footprint to the medial humeral head in the coronal and sagittal planes and divided into six clinically relevant subregions. Mean T2 values and inter- and intra-rater reliability were assessed.


RESULTS
In the anterolateral subregion, the tear group exhibited significantly higher mean T2 values (43.9 ± 12.7 ms) than the tendinosis (34.9 ± 3.9 ms; p = 0.006) and asymptomatic (33.6 ± 5.3 ms; p = 0.015) groups. In the posterolateral subregion, the tear group had higher mean T2 values (45.2 ± 13.7) than the asymptomatic group (34.7 ± 6.7; p = 0.012). Inter- and intra-rater reliability was mostly excellent (ICC > 0.75).


CONCLUSIONS
T2 mapping is an accurate non-invasive method to identify quantitatively early rotator cuff pathology. The lateral region in the coronal plane in particular may differentiate partial and small minimally retracted full-thickness tears from tendinosis and asymptomatic tendons. Understanding and being able to measure quantitatively the process of tendon degeneration and subsequent tearing may help clinicians to better predict at-risk groups and to stratify treatment options.


METHODS
III.
The Steadman Clinic, 181 W Meadow Dr, Suite 400, Vail, CO, 81657, USA.
Edmund
E
Ganal
Steadman Philippon Research Institute, 181 W Meadow Dr, Vail, CO, 81657, USA.
Charles P
CP
Ho
Steadman Philippon Research Institute, 181 W Meadow Dr, Vail, CO, 81657, USA.
Katharine J
KJ
Wilson
Steadman Philippon Research Institute, 181 W Meadow Dr, Vail, CO, 81657, USA.
Rachel K
RK
Surowiec
Steadman Philippon Research Institute, 181 W Meadow Dr, Vail, CO, 81657, USA.
W Sean
WS
Smith
Steadman Philippon Research Institute, 181 W Meadow Dr, Vail, CO, 81657, USA.
Grant J
GJ
Dornan
The Steadman Clinic, 181 W Meadow Dr, Suite 400, Vail, CO, 81657, USA. drmillett@thesteadmanclinic.com.
Peter J
PJ
Millett
D000328:Adult; D000368:Aged; D001182:Arthroscopy; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D017006:Rotator Cuff / Q000000981:diagnostic imaging* / Q000473:pathology; D000070636:Rotator Cuff Injuries / Q000000981:diagnostic imaging* / Q000473:pathology; D052256:Tendinopathy / Q000000981:diagnostic imaging* / Q000473:pathology
MRI; Partial and full tear; Rotator cuff; Supraspinatus; T2 mapping; Tendinosis