link
Bookmarks
Microinstability, Shoulder
Michael J. Tuite, MD
To access 4,300 diagnoses written by the world's leading experts in radiology, please log in or subscribe.Log inSubscribe
0
5
3
0

KEY FACTS

  • Terminology

    • Imaging

      • Top Differential Diagnoses

        • Pathology

          • Clinical Issues

            • Diagnostic Checklist

              TERMINOLOGY

              • Abbreviations

                • AIOS
                  • Acquired, often in overhead athletes
                  • Instability (micro) on examination
                  • Overstress etiology
                  • Surgery is treatment of choice
              • Synonyms

                • Microtraumatic instability
                • Sometimes used interchangeably: Superior labrum anterior cuff (SLAC) lesion, superior glenohumeral ligament (SGHL)/middle glenohumeral ligament (MGHL) tear
              • Definitions

                • Rotational or directional pathologic laxity without dislocation
                  • Tear in superior half of glenohumeral joint: Labrum, rotator interval, or MGHL
                  • Overhead throwers: Chronic stretching of anterior ligaments
                    • May occur prior to internal impingement
                • Confusing term in the literature
                  • Some include all superior labral anterior and posterior (SLAP) tears, biceps anchor tears
                • Original definition: Tear of anterosuperior labrum, SGHL, or MGHL
                  • e.g., SLAC lesion
                • Clinical diagnosis based on shoulder pain and sensation of slippage
                  • No true instability on examination

              IMAGING

              • General Features

                • MR Findings

                  • Imaging Recommendations

                    DIFFERENTIAL DIAGNOSIS

                      PATHOLOGY

                      • General Features

                        • Gross Pathologic & Surgical Features

                          CLINICAL ISSUES

                          • Presentation

                            • Demographics

                              • Natural History & Prognosis

                                • Treatment

                                  DIAGNOSTIC CHECKLIST

                                  • Consider

                                    Selected References

                                    1. Mistry A et al: Microinstability and internal impingement of the shoulder. Semin Musculoskelet Radiol. 19(3):277-83, 2015
                                    2. Chambers L et al: Microinstability and internal impingement in overhead athletes. Clin Sports Med. 32(4):697-707, 2013
                                    3. Reinold MM et al: Microinstability of the shoulder in the overhead athlete. Int J Sports Phys Ther. 8(5):601-16, 2013
                                    4. Chang EY et al: Superior labrum anterior and posterior lesions and microinstability. Magn Reson Imaging Clin N Am. 20(2):277-94, x-xi, 2012
                                    5. Drakos MC et al: Internal impingement of the shoulder in the overhead athlete. J Bone Joint Surg Am. 91(11):2719-28, 2009
                                    6. Steinbach LS: MRI of shoulder instability. Eur J Radiol. 68(1):57-71, 2008
                                    7. Woertler K et al: MR imaging in sports-related glenohumeral instability. Eur Radiol. 16(12):2622-36, 2006
                                    8. Tirman PF et al: Shoulder imaging in athletes. Semin Musculoskelet Radiol. 8(1):29-40, 2004
                                    9. Burkhart SS et al: The disabled throwing shoulder: spectrum of pathology Part I: pathoanatomy and biomechanics. Arthroscopy. 19(4):404-20, 2003
                                    10. Ruotolo C et al: Controversial topics in shoulder arthroscopy. Arthroscopy. 18(2 Suppl 1):65-75, 2002
                                    11. Savoie FH 3rd et al: Anterior superior instability with rotator cuff tearing: SLAC lesion. Orthop Clin North Am. 32(3):457-61, ix, 2001
                                    12. Pagnani MJ et al: Effect of lesions of the superior portion of the glenoid labrum on glenohumeral translation. J Bone Joint Surg Am. 77(7):1003-10, 1995
                                    Related Anatomy
                                    Loading...
                                    Related Differential Diagnoses
                                    Loading...
                                    References
                                    Tables

                                    Tables

                                    KEY FACTS

                                    • Terminology

                                      • Imaging

                                        • Top Differential Diagnoses

                                          • Pathology

                                            • Clinical Issues

                                              • Diagnostic Checklist

                                                TERMINOLOGY

                                                • Abbreviations

                                                  • AIOS
                                                    • Acquired, often in overhead athletes
                                                    • Instability (micro) on examination
                                                    • Overstress etiology
                                                    • Surgery is treatment of choice
                                                • Synonyms

                                                  • Microtraumatic instability
                                                  • Sometimes used interchangeably: Superior labrum anterior cuff (SLAC) lesion, superior glenohumeral ligament (SGHL)/middle glenohumeral ligament (MGHL) tear
                                                • Definitions

                                                  • Rotational or directional pathologic laxity without dislocation
                                                    • Tear in superior half of glenohumeral joint: Labrum, rotator interval, or MGHL
                                                    • Overhead throwers: Chronic stretching of anterior ligaments
                                                      • May occur prior to internal impingement
                                                  • Confusing term in the literature
                                                    • Some include all superior labral anterior and posterior (SLAP) tears, biceps anchor tears
                                                  • Original definition: Tear of anterosuperior labrum, SGHL, or MGHL
                                                    • e.g., SLAC lesion
                                                  • Clinical diagnosis based on shoulder pain and sensation of slippage
                                                    • No true instability on examination

                                                IMAGING

                                                • General Features

                                                  • MR Findings

                                                    • Imaging Recommendations

                                                      DIFFERENTIAL DIAGNOSIS

                                                        PATHOLOGY

                                                        • General Features

                                                          • Gross Pathologic & Surgical Features

                                                            CLINICAL ISSUES

                                                            • Presentation

                                                              • Demographics

                                                                • Natural History & Prognosis

                                                                  • Treatment

                                                                    DIAGNOSTIC CHECKLIST

                                                                    • Consider

                                                                      Selected References

                                                                      1. Mistry A et al: Microinstability and internal impingement of the shoulder. Semin Musculoskelet Radiol. 19(3):277-83, 2015
                                                                      2. Chambers L et al: Microinstability and internal impingement in overhead athletes. Clin Sports Med. 32(4):697-707, 2013
                                                                      3. Reinold MM et al: Microinstability of the shoulder in the overhead athlete. Int J Sports Phys Ther. 8(5):601-16, 2013
                                                                      4. Chang EY et al: Superior labrum anterior and posterior lesions and microinstability. Magn Reson Imaging Clin N Am. 20(2):277-94, x-xi, 2012
                                                                      5. Drakos MC et al: Internal impingement of the shoulder in the overhead athlete. J Bone Joint Surg Am. 91(11):2719-28, 2009
                                                                      6. Steinbach LS: MRI of shoulder instability. Eur J Radiol. 68(1):57-71, 2008
                                                                      7. Woertler K et al: MR imaging in sports-related glenohumeral instability. Eur Radiol. 16(12):2622-36, 2006
                                                                      8. Tirman PF et al: Shoulder imaging in athletes. Semin Musculoskelet Radiol. 8(1):29-40, 2004
                                                                      9. Burkhart SS et al: The disabled throwing shoulder: spectrum of pathology Part I: pathoanatomy and biomechanics. Arthroscopy. 19(4):404-20, 2003
                                                                      10. Ruotolo C et al: Controversial topics in shoulder arthroscopy. Arthroscopy. 18(2 Suppl 1):65-75, 2002
                                                                      11. Savoie FH 3rd et al: Anterior superior instability with rotator cuff tearing: SLAC lesion. Orthop Clin North Am. 32(3):457-61, ix, 2001
                                                                      12. Pagnani MJ et al: Effect of lesions of the superior portion of the glenoid labrum on glenohumeral translation. J Bone Joint Surg Am. 77(7):1003-10, 1995