Acromioclavicular (AC) joint injuries are one of the more common injuries of the shoulder. A recent study by Nordin et al. found that AC Joint injuries have an incidence of 2 in every 10,000 people ages 18 to 75. Most of these injuries are in young men, with more severe AC joint injuries occurring in the elderly population. AC joint injury severity is assessed radiographically. Images and patient characteristics provide indications for surgery. Damage to surrounding structures such as the AC ligament, coracoclavicular ligament, and muscle stabilizers of the shoulder are indicators of more severe damage to the AC Joint.

The Tossy and Rockwood classifications are two of the most commonly used radiographic systems in the evaluation of AC joint injury severity. Tossy has three categories: AC sprain, AC subluxation, and AC dislocation. Rockwood has six more specific categories: Damage to AC ligament (I), rupture of AC ligament and damage to coracoclavicular ligament (II), rupture of both AC and Coracoclavicular ligament (III), posterior dislocation of AC joint (IV), high-grade superior dislocation with rupture of dynamic stabilization mechanism (V), and inferior dislocations of AC joint (VI). Non-surgical treatments are recommended for types I and II, and surgery is indicated for types IV and VI. There is controversy surrounding the surgical vs. non-surgical approach in types III and V.

The sternoclavicular (SC) joint has its own variety of ligamentous injuries, similar to that of the AC joint. However, its anatomical position of dislocations is either anterior or posterior. Anterior dislocation can often be resolved with closed reduction versus posterior dislocation, which may need open reduction and is more severe due to the critical anatomy residing posterior to the clavicle. Injury to the SC joint is much less common. One retrospective study found an incidence of just 0.9% of all shoulder girdle injuries seen at a level 1 trauma center over 19 years.

This review aims to look at the non-surgical treatment of AC and SC joint injuries. Specifically, muscle energy techniques that are utilized in osteopathic manipulative treatment. Muscle energy is a technique typically used to treat hypertonic muscles and restricted joints. It applies to structures throughout the body, especially the AC and SC joints. The isometric variation of the muscle energy technique is most commonly used, and includes the following steps :

Localization of the restrictive barrier of the muscle/joint under evaluation

The patient actively contracts muscle/joint in a specific direction for a specific amount of time (usually 3 to 5 seconds)

Counterforce is being applied by the provider during this 3 to 5-second interval.

The patient relaxes after this 3 to 5-second interval.

The provider takes the muscle/joint being treated further into the restrictive barrier.

Steps #2 through 5 are repeated (typically done 3 to 5 times total)