Orthopedic Teaching Cases 2023, Jan, 18 | 12:00 am

Shoulder and Elbow cases Hill–Sachs lesion

A 17-year-old, football player with a history of multiple, left shoulder dislocations and an attempted arthroscopic repair presents to your clinic with continued right shoulder pain and instability. He has been unable to return to competition and comes to see you for a second opinion. A CT image is shown below (Fig. 2–42).

 

 

 

Figure 2–42

 

What injury should have been addressed during his index procedure?

  1. Hill–Sachs lesion

  2. PASTA lesion

  3. ALPSA lesion

  4. Bursal-sided rotator cuff tear

  5. Articular-sided rotator cuff tear

 

Discussion

The correct answer is (A). The imaging demonstrates an axial CT scan with a large Hill–Sachs lesion. The lesion involves a large component of the humeral head (>40%) and as such is likely clinically significant. As the humerus is rotated externally the Hill–Sachs lesion is brought closer to the anterior rim of the glenoid and eventually engages the glenoid. Patients may perceive this as a painful click or locking episode. Lesions that involve 40% of the humeral head should be repaired to adequately address instability. The other answer choices all represent injuries that may be associated with a shoulder dislocation, although the large Hill–Sachs lesion is most responsible for his ongoing instability.

Hill–Sachs lesions are compression fractures of the posterosuperolateral

humeral head that occur when the head comes in contact with the glenoid during an acute anterior dislocation or after recurrent instability events. The relative incidence of these lesions is high, and it approaches 100% in patients with recurrent instability. It is important to understand that these lesions are bipolar—there is anterior glenoid damage in addition to the Hill–Sachs lesion; both of these must be addressed to optimize outcome. Lesions can be classified as engaging or nonengaging. Engaging lesions are oriented such that the long axis of the lesion is parallel to the anterior glenoid rim in the position of athletic function, i.e., abduction and external rotation. Engaging lesions tend to be more symptomatic, and instability may be associated with a sensation of catching or locking.

Physicians should obtain a complete set of x-rays. Special views include the modified Westpoint axillary (Fig. 2–43B) to evaluate for glenoid loss and the stryker notch view (Fig. 2–43A) to evaluate the Hill–Sachs lesion. This view brings the posterolateral defect into direct visualization. 3D CT imaging is also very useful for evaluating glenoid bone loss and estimating the size of the Hill–Sachs lesion.

 

 

 

Figure 2–43 A: Stryker notch view. B: West point axillary view. (From Bucholz RW and Heckman JD.

Rockwood and Green’s Fractures in Adults 7e. Philadelphia: Wolters Kluwer, 2009.)

 

As with most instability situations, treatment begins with conservative treatment in the form of PT, focusing on dynamic stabilizer strengthening. Should patients fail a course of PT, surgery is the next step. This will involve a labral repair, possible glenoid bony augmentation, and capsular shift (as is typical for most instability cases). The provider must also decide whether or not the Hill–Sachs lesion is clinically significant and whether it needs to be addressed surgically. Lesions that

involve:

 

 

<20% of the humeral head are considered to be clinically insignificant. 20% to 40% may be significant.

 

>40% are significant and contribute to recurrent instability.

In addition, “engaging lesions” are considered to be clinically significant and warrant treatment. Surgical options include: humeral head bone augmentation with disimpaction and bone grafting or allograft, Remplissage procedure, or humeral head resurfacing. The most commonly used procedure is the Remplissage procedure, which involves filling in the humeral defect with a portion of the infraspinatus tendon. This is often done using an arthroscopic technique with suture through the infraspinatus tendon and a bone anchor placed directly in the defect.

Additional Questions

A 34-year-old female with recurrent anterior dislocations and a prior anterior arthroscopic capsulolabral repair presents to your clinic with continued instability episodes and pain. Her imaging demonstrates about 10% of bone loss on the anterior glenoid and a Hill–Sachs lesion that measures 40% of her humeral head.

Treatment options could include all of the following except

  1. Humeral head resurfacing

  2. Disimpaction and bone grafting of the humeral head defect

  3. Remplissage

  4. Filling in the bony defect with rotator cuff tendon

  5. Latarjet procedure

 

Discussion

The correct answer is (E). A Hill–Sachs lesion (Fig. 2–44) that involves 40% of the humeral head is likely to be symptomatic. In addition to a labral repair and capsular shift, the patient will require: a humeral head resurfacing (Answer A), disimpaction and bone grafting (Answer B), or Remplissage to address the Hill–Sachs. Answer D merely describes a Remplissage procedure. Which procedure is chosen depends on the extent of the lesion. Greater damage to the humeral head, for example, will make resurfacing a more attractive option. A Latarjet procedure (Answer E) is indicated for glenoid bone loss >20% and is probably unnecessary here.

 

 

Figure 2–44 CT scan demonstrating a Hill–Sachs lesion.

 

The best view to visualize a Hill–Sachs lesion on radiographs is?

  1. With the patients hand above his head and the x-ray beam directed 10 degrees cephalad

  2. With the patients hand by their side and the x-ray beam directed 10 degrees cephalad

  3. An AP view with the arm in 40 degrees of external rotation

  4. An axillary view

  5. A serendipity view

 

Discussion

The correct answer is (A). This describes the stryker notch view, which is the best way to visualize the posterolateral humeral head where a Hill–Sachs lesion is most commonly located. Answer B describes a Zanca view, which is used to visualize the AC joint. Answer C does not have a common eponym, although this view can be helpful when evaluating proximal humerus fractures, glenohumeral arthritis, or glenoid fractures. An axillary view (Answer D) is useful when evaluating anterior or posterior dislocation. A serendipity view (Answer E) is taken with the beam directed 40 degrees cephalad aiming at the clavicle; it is used to visualize the SC joint and the clavicle.