The Upper Trapezius muscle (UT) is a muscle that is frequently accused of being responsible for dysfunction related to neck or shoulder impairments for being "too active" or "tight." We have even heard physical therapists exclaim how they hate seeing people try to strengthen their UT, because they feel people are overusing the muscle, and it is already too strong compared to the other muscles. While this is certainly possible, how frequently does this actually occur? Let's review the anatomy first (Kendall, 2005):
With the common perception that the UT is often short (especially with patient reports of the muscle feeling "tight" when put on stretch - of course), it is not surprising that stretching is frequently prescribed for the muscle in patients with neck and/or shoulder pain. That's not to say it is never warranted. If the muscle length is truly assessed and found to be adaptively shortened (and non-painful), of course we want to stretch the muscle. However, we must be certain that the muscle is indeed shortened first.
If the UT is truly shortened, you will find the entire shoulder heightened compared to normal, meaning both the superior angle and acromion of the scapula. Often patients are seen with an elevated superior angle but depressed acromion, suggesting a downwardly rotated scapula - components of an overactive/shortened levator scapula. An exercise commonly performed at the gym involved shoulder shrugs holding weights with the idea that the individual is strengthening the UT. However, in this position, the scapula is rotated downward and results in strengthening/reinforcing the levator scapula muscle (Sahrmann, 2002). An overactive UT is also frequently accused as the culprit in shoulder impingement. However, remember that about 1/3 of shoulder elevation is due to upward rotation of the scapula, an action of the UT. Frequently, the patient will display elevation of the scapula when trying to flex or abduct the humerus. Attention should be paid to whether or not the scapula is in upward or downward rotation with that elevation. If it appears to be downward rotation, it is essential that the UT undergoes retraining. In order to focus on the UT, the shoulders should be placed in at least 90 degrees of elevation in order to place the scapula in upward rotation and allow the shrugging aspect of the motion to come from the UT, not just the levator scapula.
An additional point that should be considered is the impact on the cervical spine. Sahrmann places a strong emphasis on relative stiffness and hypermobility vs. hypomobility in her teachings. As previously discussed, the UT attaches to the cervical spine and, in doing so, can be responsible for pain at the attachment site. There are at least two possible reasons for cervical pain resulting from UT impairment. One, the UT is overactive and stronger compared to the cervical intrinsic muscles. When the muscle contracts such as during upper extremity elevation, cervical extension or rotation is frequently seen (Sahrmann, 2002). You can even feel the individual cervical vertebrae rotating during shoulder flexion/abduction. This hypermobility (a precursor to hypomobility) provides the excess stress that can lead to degeneration and, in the long run, hypomobility. In this case, the UT needs to be retrained with an emphasis placed on maintaining cervical stability and neutral cervical positioning. Two, the UT is insufficient and lengthened, resulting in a pull on the proximal attachment (cervical vertebrae) due to the weight of the scapula and upper extremity, especially during movements. These patients, too, will report that "stretching feels good." Just as the previous example, however, we must strengthen the UT in these patients, with proper positioning as explained earlier.
The purpose of this post was to make us all more aware and pay specific attention to the scapulohumeral positioning both statically and dynamically in order to determine the true impairment that lies with the UT, or if there even is one at all. A starting point we like to use is assessing the medial side of the scapula at rest to determine if the resting position is upward or downward rotation. That should be followed up with a comparison of the superior angle of the scapula to the acromion as well to aid in confirmation. This positioning should then be tracked during flexion/abduction of the humerus. This is just one muscle's impact on the upper quarter, but as you can tell, it is a significant one. For more information on the topic, it is recommended you review the references listed below.
Kendall FP, McCreary EK, Provance PG, Rodgers MM, & Romani WA. Muscles Testing and Function with Posture and Pain. 5th edition. Baltimore, MD: Lippincott Williams & Wilkins, 2005. 326. Print.
Sahrmann, SA. Diagnosis and Treatment of Movement Impairment Syndromes. St. Louis, MO: Mosby, 2002. 206-208. Print.