Indoor Skydiving: An Emerging Cause of Anterior Shoulder Dislocations

Abstract

Background: The risks of indoor skydiving have not been extensively studied. Indoor skydiving facilities are often used for corporate events and parties and by relatively inexperienced participants who may not appreciate the risks involved. The abducted and externally rotated shoulder position, combined with nearby walls, tight spaces, and the strong airstream, has resulted in a pattern of shoulder dislocation injuries. Case Report: A 26-year-old male presented with recurrent left shoulder instability after developing an engaging Hill-Sachs lesion following traumatic anterior shoulder dislocation while indoor skydiving. He entered the wind tunnel with his arms abducted and externally rotated. The wind created an upward force that held his arms in this position. As he reached with his left arm for the side of the tunnel to exit, his arm was forced into further external rotation, dislocating the shoulder. The patient was treated arthroscopically with a remplissage procedure and repair of the glenoid labrum. Postoperatively, he resumed his active lifestyle and sports without further dislocations or instability. Conclusion: Indoor skydiving may pose a high risk of anterior dislocation because the shoulder is forced into abduction and external rotation in the free-fall position. We advise caution before participation in indoor skydiving by any individual, but especially those with a history of shoulder instability.

Keywords: Athletic injuries; Bankart lesions; labral injuries; shoulder dislocation.

Figure 1.

Illustration demonstrating the mechanism of shoulder dislocation. The patient is in the wind tunnel with his arms abducted and externally rotated, with the wind pushing his arms into further external rotation. When he reached for the side of the wind tunnel while attempting to exit, his left arm was forced into further external rotation, causing an anterior dislocation of the left shoulder. (Original art by Daniel M. Zumsteg, MD. Published with permission.)

Figure 2.

Computed tomography scan of the left shoulder, axial cross-sectional image, demonstrates mild compression, or Bankart lesion, of the anterior glenoid fossa over a 1.1-cm area (upper arrows, anterior) and a Hill-Sachs lesion measuring 1.4 cm × 0.3 cm on the humeral head (lower arrows, posterior).

Figure 3.

Computed tomography scan of the left shoulder, sagittal cross-sectional image, shows the Hill-Sachs lesion on the posterior humeral head (arrow).

Figure 4.

Three-dimensional reconstruction of the left shoulder shows the Hill-Sachs lesion on the posterior humeral head (arrow).

Figure 5.

Arthroscopic image within the shoulder joint shows the humeral head dislocating while in 30° of forward flexion and neutral rotation.

Figure 6.

Arthroscopic image within the shoulder joint shows the humeral head perched and a large Hill-Sachs lesion. A percutaneous suture passer is placing suture in the Hill-Sachs lesion.