Book contents
- Frontmatter
- Contents
- List of contributors
- Foreword
- Preface
- Section 1 Shoulder
- Case 1 Pseudocyst of the humeral head
- Case 2 SLAP tear versus sublabral foramen/recess
- Case 3 SLAP tear versus normal variant of biceps labral complex
- Case 4 Labral tear versus hyaline cartilage undercutting
- Case 5 Buford complex of the shoulder
- Case 6 Pseudosubluxation of the shoulder
- Case 7 Posterior dislocation of the shoulder
- Case 8 Avulsion fracture of the greater tuberosity
- Case 9 Parsonage–Turner versus quadrilateral space syndrome
- Case 10 ABER positioning during MR arthrogram: anterior labral tears
- Case 11 Os acromiale
- Case 12 Hill–Sachs injury versus normal flattening of posterolateral humeral head
- Case 13 Red marrow versus tumor in the proximal humeral shaft
- Case 14 Kim's lesion
- Case 15 Internal impingement of the shoulder
- Section 2 Arm
- Section 3 Elbow
- Section 4 Forearm
- Section 5 Wrist
- Section 6 Hand
- Section 7 Hip and Pelvis
- Section 8 Thigh
- Section 9 Leg
- Section 10 Ankle
- Section 11 Foot
- Section 12 Tumors/Miscellaneous
- Index
- References
Case 15 - Internal impingement of the shoulder
from Section 1 - Shoulder
Published online by Cambridge University Press: 05 July 2013
- Frontmatter
- Contents
- List of contributors
- Foreword
- Preface
- Section 1 Shoulder
- Case 1 Pseudocyst of the humeral head
- Case 2 SLAP tear versus sublabral foramen/recess
- Case 3 SLAP tear versus normal variant of biceps labral complex
- Case 4 Labral tear versus hyaline cartilage undercutting
- Case 5 Buford complex of the shoulder
- Case 6 Pseudosubluxation of the shoulder
- Case 7 Posterior dislocation of the shoulder
- Case 8 Avulsion fracture of the greater tuberosity
- Case 9 Parsonage–Turner versus quadrilateral space syndrome
- Case 10 ABER positioning during MR arthrogram: anterior labral tears
- Case 11 Os acromiale
- Case 12 Hill–Sachs injury versus normal flattening of posterolateral humeral head
- Case 13 Red marrow versus tumor in the proximal humeral shaft
- Case 14 Kim's lesion
- Case 15 Internal impingement of the shoulder
- Section 2 Arm
- Section 3 Elbow
- Section 4 Forearm
- Section 5 Wrist
- Section 6 Hand
- Section 7 Hip and Pelvis
- Section 8 Thigh
- Section 9 Leg
- Section 10 Ankle
- Section 11 Foot
- Section 12 Tumors/Miscellaneous
- Index
- References
Summary
Imaging description
The constellation of findings of undersurface tears of the supraspinatus or infraspinatus tendon and cystic changes in the posterior aspect of the humeral head associated with posterosuperior labral pathology is a consistent finding diagnostic of internal impingement (Figures 15.1 and 15.2).
Importance
Internal impingement, also known as posterosuperior impingement, is a condition that occurs in athletes in which the shoulder is put in extreme abduction and external rotation during overhead movements.
Typical clinical scenario
Impingement of the rotator cuff on the posterosuperior glenoid labrum is a cause of posterior shoulder pain in athletes who throw. Patients present with posterosuperior shoulder pain that is sometimes associated with anterior instability.
Differential diagnosis
Cystic lesions are commonly visible in the posterosuperior portions of the humeral heads, the bare areas, just posterior to the greater tuberosity on shoulder MR images. Posterior cyst-like changes along with the changes in the rotator cuff and posterosuperior labrum should suggest internal impingement. Intraosseous humeral cysts in the posterior aspect of the greater tuberosity that communicate with the joint would appear to be incidental findings.
Teaching point
MR arthrography may allow detection of abnormalities associated with internal impingement.
- Type
- Chapter
- Information
- Pearls and Pitfalls in Musculoskeletal ImagingVariants and Other Difficult Diagnoses, pp. 27 - 29Publisher: Cambridge University PressPrint publication year: 2013