Shoulder and Elbow cases multidirectional instability (MDI)

A 17-year-old gymnast presents to clinic with right shoulder pain. She denies any specific injury but reports increasing shoulder pain over the last 6 months. On examination, she has generalized hyperlaxity of her joints. Her bilateral shoulders demonstrate a positive sulcus sign, and her right shoulder is painful when placed in an internally rotated and flexed position as well as when placed in an abducted and externally rotated position.

What would be the most appropriate initial treatment?

1. Physical therapy

2. Cortisone injection

3. Cortisone injection + physical therapy

4. Shoulder immobilizer

5. Arthroscopic capsular shift

 

Discussion

The correct answer is (A). This patient’s presentation is consistent with generalized hyperlaxity and multidirectional shoulder instability (MDI) in the right shoulder. It is important to differentiate these terms, as hyperlaxity implies that the patient does not have symptoms of pain or instability and does not require any treatment. Patients with hyperlaxity, however, are predisposed to developing symptomatic shoulder instability, which does require treatment. The initial treatment is usually physical therapy. There is little role for a cortisone injection (Answers B, C) in a young patient with instability. Shoulder immobilization (Answer D) may be recommended by some providers although there is no evidence to support this. Surgical treatment (Answer E) is not the initial treatment.

MDI can be defined as symptomatic shoulder instability in 2 or more directions with or without associated hyperlaxity. It is most commonly seen in overhead athletes, specifically swimmers, throwers, volleyball players and gymnasts, and is usually diagnosed in the second or third decade. It is uncommon in older individuals. Both generalized hyperlaxity and cumulative microtrauma are thought to be contributing factors.

Patients usually present with insidious onset of pain and symptoms that are recreated in specific positions. It is important to elicit what positions or activities are most uncomfortable, as this will clue the provider into the direction of primary instability. Physical examination will demonstrate a positive sulcus sign, load and shift as well as apprehension and relocation tests. The most high yield imaging modality is an MRA which may demonstrate a large patulous capsule and may show associated injuries such as a labral tear.

Treatment is initially conservative in the form of physical therapy. The goal is to strengthen the dynamic stabilizers of the shoulder and periscapular muscles, which often exhibit dyskinesia in multidirectional instability (MDI). This is most successful in patients who do not have a history of a specific traumatic event. Surgical treatment most often involves arthroscopic labral repair and capsular plication. The plication is done starting from the direction of primary instability and working from inferior to superior; the magnitude of plication is subjectively

measured at the time of surgery.

Additional Questions

A 17-year-old, male, volleyball player presents to your office with shoulder pain and instability. He underwent a thermal plication at an outside hospital 2 months ago and reports that, in addition to continued instability, his shoulder feels weaker than it previously did.

What muscle and nerve is most likely affected?

1. Deltoid, axillary

2. Teres minor, axillary

3. Subscapular, nerve to subscapularis

4. Supraspinatus, nerve to supraspinatus

5. Teres major, axillary

 

Discussion

The correct answer is (B). Thermal plication was previously considered a viable treatment option for a patulous capsule, although more recent studies have demonstrated that it is no longer an acceptable option. One of the known complications of thermal plication is damage to the teres minor branch of the axial nerve. Cadaver studies have demonstrated that the nerve runs just 12.4 mm below the glenoid rim at the 6 o’clock position and runs 2.5 mm deep to capsule (see Fig. 2–41). Adduction and external rotation tends to move the nerve further away from the capsule into a less dangerous position. Denervation of the deltoid (Answer A) is also a possible complication, although it is less common than denervation of the teres minor. The subscapular nerve (Answer C) and supraspinatus nerve (Answer D) are generally not in the surgical field. The teres major (Answer E) is innervated by the subscapular nerve, not the axillary nerve.

 

 

Figure 2–41 Illustration of the axillary nerve course about the shoulder. (Reproduced with permission from Price MR, Tillett ED, Acland RD, et al. Determining the Relationship of the Axillary Nerve to the Shoulder Joint Capsule from an Arthroscopic Perspective. J Bone Joint Surg Am, 2004 Oct; 86 (10): 2135–2142.)

 

A competitive high school swimmer complains of increasing left shoulder pain during practice since the beginning of his senior season. Examination reveals a positive anterior and posterior load and shift test, apprehension test, and a 2 cm sulcus sign. He has been treated with a dynamic stabilizer-strengthening program and activity modification, but he continues to be symptomatic.

The next step in management should be?

1. Immobilization in a brace for 6 weeks

2. Arthroscopic anterior and posterior capsular plication and labral repair

3. Arthroscopic rotator interval closure

4. Arthroscopic thermal capsular plication and rotator interval closure

5. Cortisone injection and continued PT

 

Discussion

The correct answer is (B). In a young, symptomatic athlete, if conservative treatment fails, the next step involves anterior and posterior capsular plication and labral repair if required. Immobilization (Answer A) is commonly employed postoperatively but is not used as an independent treatment modality. The role of either medial to lateral or superior to inferior rotator interval closure (Answer C) has been debated. It is sometimes utilized as an additional procedure if a shoulder continues to demonstrate instability even after capsular plication. This is usually an intraoperative decision. One of the negatives of rotator interval closure is that it restricts external rotation with the arm by the side. Thermal plication (Answer D) is

no longer used and there is little role for a cortisone injection (Answer E) in a young athlete with MDI.

A 23-year-old female comes to your clinic with her mother. She recounts a history of seeing multiple orthopaedic providers with a variety of complaints and receiving little relief from their treatments. Today, her main complaint is a history of recurrent shoulder dislocations. She is voluntarily able to dislocate her shoulder anteriorly in clinic and demonstrates this several times. She reports that she has been able to do this for as long as she can remember. She has developed discomfort in this shoulder recently and is now seeking treatment options.

The next step should include?

1. Physical therapy

2. Psycological evaluation

3. Diagnostic arthroscopy

4. Cortisone injection

5. Temporary shoulder immobilization

 

Discussion

The correct answer is (B). When evaluating patients with instability, it is important to address the issue of voluntary control. There is a well-described subset of patients who use voluntary dislocation as a means of gaining attention. These patients are best managed with a psychological examination, as surgical treatment will quite likely fail. Two other types of nonpsychiatric voluntary dislocation have been described. The muscular type where selective activation of muscles results in a dislocation and the positional type where assuming a provocative position will result in a dislocation. The muscular type is best treated with biofeedback techniques whereas the positional type will do well with surgery.

Which of the following describes a patient with MDI who would most benefit from surgical stabilization?

1. A 17-year-old girl who is able to voluntarily dislocate her shoulder and readily demonstrated this in clinic

2. A 19-year-old swimmer who has had increasing shoulder pain over the last 6 months and examination consistent with MDI

3. A 22-year-old, professional football player with long standing complaints of shoulder instability seen in the preseason

4. An 18-year-old, late-season, collegiate football player with long standing complaints of shoulder subluxations and a recent frank dislocation

5. A 22-year-old male with a diagnosis of Marfan’s syndrome shoulder pain and instability

Discussion

The correct answer is (D). Answer A describes a patient who can voluntarily dislocate her shoulder and does so repeatedly in clinic. Voluntary dislocators must be thoroughly evaluated to ensure that there is no psychological component to their dislocations. A patient who is dislocating for secondary gain will do very poorly with surgery. Answer B describes a patient with MDI without any specific trauma. It would be most appropriate to start with physical therapy in this patient. Answer C represents a pre-season athlete with no specific trauma. Pre- and early season athletes with chronic complaints, without concerning radiographic abnormalities, may benefit from rehab and return to play as soon as possible in the same season. Should they continue to be symptomatic, surgery or further PT would be appropriate in the immediate postseason. Answer D is the most appropriate surgical candidate presented. This patient, at the end of his season, will not have enough rehab time to allow him to return to the field this season. Early surgery may be appropriate to allow the patient a maximum amount of rehab time prior to the next season. Patients with connective tissue disorders (Answer E) tend to have poorer outcomes with surgical intervention.

 

Objectives: Did you learn...?

 

 

To appreciate the difference between hyperlaxity and instability? The common presentation of MDI?

 

To appreciate the commonly used treatment options?