Skeletal Radiology

, Volume 23, Issue 8, pp 641–645

The coracoacromial arch: MR evaluation and correlation with rotator cuff pathology

  • Timothy E. Farley
  • Christian H. Neumann
  • Lynne S. Steinbach
  • Steve A. Petersen
Articles

DOI: 10.1007/BF02580386

Cite this article as:
Farley, T.E., Neumann, C.H., Steinbach, L.S. et al. Skeletal Radiol. (1994) 23: 641. doi:10.1007/BF02580386

Abstract

The relative prevalence of various acromial shapes, appearance of the coracoacromial ligament and enthesophytes along the inferior aspect of the acromioclavicular joint in patients with and without rotator cuff tears were evaluated. Of 76 patients with clinical instability and impingement, 31 had a normal rotator cuff and 45 demonstrated a partial or full tear of the supraspinatus tendon at surgery. Results were compared with those from magnetic resonance (MR) scans of 57 asymptomatic volunteers. Of the 45 patients with a supraspinatus tear, 38% (17) had a flat acromial undersurface (type I), 40% (18) had a concave acromial undersurface (type II), 18% (8) had an anteriorly hooked acromion (type III), and 4% (2) had an inferiorly convex acromion (type IV). Among the 31 patients with a normal rotator cuff at surgery and the 57 asymptomatic volunteers, the respective prevalences of the type I acromion were 39% (12) and 44% (25), of type II 48% (15) and 35% (20), type III 3% (1) and 12% (7), and type IV 10% (3) and 9% (5). Shoulders with surgically proven rotator cuff tears showed a tendential association with a type III acromion (8/45) and statistically significant associations with a thickened coracoacromial ligament (17/45) and acromioclavicular enthesophytes (18/45). For the association between inferiorly directed acromioclavicular joint enthesophytes and rotator cuff tears, age appears to be a confounding factor. The type IV acromion, newly classified by this study, does not have a recognizable association with rotator cuff tears. Assessment of the osseous-ligamentous coracoacromial outlet by may prove helpful to the orthopedic surgeon in patients for whom surgical decompression is contemplated.

Key words

Shoulder MR Rotator cuff tear Acromion Subacromial outlet 

Copyright information

© International Skeletal Society 1994

Authors and Affiliations

  • Timothy E. Farley
    • 1
    • 2
  • Christian H. Neumann
    • 1
    • 3
    • 4
  • Lynne S. Steinbach
    • 4
  • Steve A. Petersen
    • 5
  1. 1.Department of RadiologyDesert HospitalPalm SpringsUSA
  2. 2.Department of Diagnostic RadiologyFlorida HospitalOrlandoUSA
  3. 3.Desert HospitalDepartment of RadiologyPalm SpringsUSA
  4. 4.Department of RadiologyUniversity of California San FranciscoSan FranciscoUSA
  5. 5.Department of Orthopedic SurgeryWayne State University School of MedicineDetroitUSA