Bankart lesion

Bankart lesion

• refers to an injury of the labrum and associated glenohumeral capsule/ligaments
• injury to these reinforcing soft tissue structures is thought to predispose to recurrent dislocation (1)
• occur as a direct result of anterior dislocation of the humeral head, whereby the humerus is compressed against the labrum
  • s detachment of the anteroinferior labrum from the underlying glenoid, and the labral tear may further extend further superiorly or posteriorly. Impaction fracture of the anteroinferior glenoid margin commonly co-occurs

"bony Bankart" (contrasted with a "soft Bankart" or "fibrous Bankart")

• often used to refer to fracture of the adjacent anteroinferior glenoid, an injury which also commonly occurs in the setting of anterior glenohumeral dislocation. Structurally, this fracture is thought to be less contributory to anterior instability

"Soft" Bankart lesions are more common than "bony" Bankart lesions (2)

The same mechanism of compression can result in a Hill-Sachs lesion

• Bankart and Hill-Sachs lesions are 11x more likely to occur together than isolated injuries (2)

HSL is often linked with recurrent anterior shoulder instability

• a compression fracture of the posterolateral humeral head due to its compression against the anteroinferior part of the glenoid when the humerus is anteriorly dislocated
• the anatomical apposition gives a characteristic position of the lesion; the comparable injury caused by posterior dislocation is a reverse Hill-Sachs lesion
• demonstrated in 67–93% of anterior dislocations and can reach an incidence rate of 100% in patients with recurrent anterior shoulder instability (3)
• typically occurs with an anteroinferior glenohumeral dislocation event
• young age and hyperlaxity of the ligaments surrounding the glenohumeral joint lead to a predisposition for recurrence of dislocation

Reference:

• (1) Bankart ASB. Recurrent or Habitual Dislocation of the Shoulder-Joint. (1923) Br Med J;2:1132
• (2) Horst K, Von Harten R, Weber C et-al. Assessment of coincidence and defect sizes in Bankart and Hill-Sachs lesions after anterior shoulder dislocation: a radiological study. Br J Radiol. 2004;87 (915): 20130673.
• (3) Maio M et al. How to measure a Hill–Sachs lesion: a systematic review. EFORT Open Rev 2019;4:151-157.