Distance between the supraspinatus and long head of the biceps tendon on sagittal MRI: a new tool to identify anterior supraspinatus insertion injury

Abstract

Purpose Anterior insertion of the supraspinatus muscle plays an essential role in rotator cuff tissue. We aimed to determine whether the distance between the midpoints of the supraspinatus central tendon and long head of the biceps tendon on a sagittal shoulder magnetic resonance imaging scan can help to preoperatively diagnose an injury of the anterior insertion of the supraspinatus. Method This retrospective study reviewed 103 patients with a full-thickness supraspinatus tendon tear: 50 patients with (injured group) and 53 patients without (intact group) anterior supraspinatus insertion tear. The inter-tendon distance was measured based on an oblique sagittal magnetic resonance imaging scan. SPSS was used for statistical analyses. Two independent samples t-test and receiver operating curve analysis were also performed. Results The measurements of inter-tendon distance revealed good intra- and inter-observer reliabilities with intra-class correlation coefficients of 0.92 and 0.97, respectively. The inter-tendon distance of the injured group was significantly greater than that of the intact group (10.1 ± 2.7 vs 8.0 ± 2.3 mm, P < 0.001). The diagnostic ability of the inter-tendon distance was fair (area under the curve = 0.745), and a threshold of 9 mm had a specificity of 73% and sensitivity of 74%. Conclusion The distance between the supraspinatus central tendon and long head of the biceps tendon on magnetic resonance imaging was greater in patients with anterior supraspinatus insertion injury than those without the injury. A distance of 9 mm may be the cut-off value and a good diagnosis marker for anterior supraspinatus insertion injury. Level of evidence Level III, diagnostic case–control study.

The Correlation between Variation of Labral Attachment and Lesions of the Long Head of the Biceps Tendon in Patients with Rotator Cuff Tears

“…Subgroup analysis showed the percentages of healthy LHBT in these three RCT groups were 65.4%, 43.2% and 21.2% respectively. It is obvious that the incidence of LHBT pathology is directly proportional to the extent of RCT, which consistent with previous literatures 12,29–31 …”

“…It is obvious that the incidence of LHBT pathology is directly proportional to the extent of RCT, which consistent with previous literatures. 12,[29][30][31] Limitations Several limitations of this study influenced the findings and statistical associations. First, the classification of the LHBT labrum distribution and LHBT lesion is totally subjective, a discrepancy that may exist from different studies.…”

“…But the exact mechanism of variant LHBT lesions in RCT patients yet to be determined and need further investigation. According to above mentioned studies, the anatomic variation of LHBT, especially its' labral attachment, may play an important role on LHBT lesions in RCT patients 11–13 …”

“…According to above mentioned studies, the anatomic variation of LHBT, especially its' labral attachment, may play an important role on LHBT lesions in RCT patients. [11][12][13] Traditionally, the LHBT is described as arising from the supraglenoid tubercle and the glenoid labrum. Vangsness et al 14 first described the variability of the labral attachment of the LHBT based on studying 100 fresh frozen shoulders from cadavers of both genders, which aged from the third to the ninth decade.…”

“…According to above mentioned studies, the anatomic variation of LHBT, especially its' labral attachment, may play an important role on LHBT lesions in RCT patients. 11 , 12 , 13 …”