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Throwers Exostosis

Bennetts View xray

synonyms: Bennett's lesion

Throwers Exostosis ICD-9

Throwers Exostosis Etiology / Epidemiology / Natural History

  • Throwers exostosis = bony posterioinferior prominencde at the posterior insertion of the inferior glenohumeral ligament.
  • Felt to be related to repetitive throwing leading to traction osteophyte formation.
  • Occurs in 20% of major league pitchers (Wright RW, AJSM 2004;32:121). Generally asymptomatic

Throwers Exostosis Anatomy

Throwers Exostosis Clinical Evaluation

  • Posterior shoulder pain during ball release
  • LocaI discomfort and tenderness in the posterior shoulder with referred pain to the deItoid region.
  • May be unable to continued throwing due to posterior shoulder, and referred deltoid pain.

Throwers Exostosis Xray / Diagnositc Tests

  • Bennett's or modified Bennett's view of the shoulder demonstrates exostosis on inferior aspect of glenoid.

Throwers Exostosis Classification / Treatment

  • Shoulder arthroscopy, joint capsule incised on the posterior side of the labrum directly over the exostosis. Exostosis then resected with shaver or bur.

Throwers Exostosis Associated Injuries / Differential Diagnosis

Throwers Exostosis Complications

  • Inabilitly to return to pre-op level

Throwers Exostosis Follow-up Care

  • 55% return to preinjury level of competition after arthroscopic excision (Meister K, AJSM 1999;27:133)

Throwers Exostosis Review References

  • Wright RW, AJSM 2004;32:121
  • Meister K, AJSM 1999;27:133
  • Bennett GE: Elbow and shoulder lesions of baseball players. Am J Surg 98: 484–492, 1959
  • Bennett GE: Shoulder and elbow lesions distinctive of baseball players. Ann Surg 126: 107–110, 1947
  • Bennett GE: Shoulder and elbow lesions of the professional baseball pitcher. J Am Med Assoc 117: 510–514, 1941




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