Welcome to the November e-newsletter. Before jumping headfirst into the therapeutic section, I would first like to thank all the wonderful people who stopped at our AMTA National Convention booth. The convention exhibit hall was open for 13 hours over three days, and my teaching assistants and lovely wife worked very hard keeping up with all the visitors. Meantime, they had me working non-stop on the 52 attendees who signed up for 15-minute mini-sessions….Quite a challenging task but well worth it!

In this issue, we continue the mobilization tour through upper extremity structures. Assessing and correcting range of motion (ROM) issues at each joint prior to treating specific soft-tissue conditions has proven to be a very effective strategy for structurally-integrated, pain-management therapists. Since joints and associated soft tissues must work together harmoniously, restoring ROM to one always benefits the whole. 

Recall in the September newsletter we discussed assessment and treatment corrections for two common restrictions at the sternoclavicular joint. The October newsletter focused on restoring joint-play to three dysfunctional motions at the acromioclavicular joint…AND NOW…we tackle a very complex bony articulation that can be restricted in at least ten different anatomical positions. 

The Glenohumeral Joint

Figure 1. Pear-shaped glenoid fossa and associated glenohumeral structures. Adapted from Scott Bodell with permission

When people refer to the shoulder joint they're usually talking about the glenohumeral joint; the ball-and-socket which links the upper arm to the body through the clavicle. This joint has been compared to a golf ball sitting on a tee. The large rounded end of the humerus moves within the shallow, scooped-out glenoid next to the end of the clavicle (see Figure 1). Because the arm moves through an extremely wide ROM (often under very heavy mechanical loads), the glenohumeral faces unique challenges in comparison to other joints when it comes to stability and restrictions of motion.

To understand the mechanisms of glenohumeral stability, it is helpful to compare this joint with the hip and knee. The hip, with its ball and socket configuration, has intrinsic mechanical stability and a truncated spherical ROM. In contrast, the knee has minimal intrinsic bony stability and must rely on a complex array of ligaments for its stability. The shoulder borrows from both of these mechanisms with modifications that provide less stability and greater ROM.

The glenoid itself offers minimal intrinsic stability on the basis of its bony anatomy. Even with the addition of cartilage and a labrum, the enclosed glenoid surface area is 1/3 that of the humeral head, so it cannot capture the humeral head as occurs in the hip. Therefore, stability of the glenohumeral joint depends on soft tissue integrity, including the rotator cuff muscles, the cartilaginous glenoid labrum, and the joint capsule working synchronistically with the glenohumeral ligaments.

Figure 2. Upper Crossed Syndrome: This posture develops as tight pecs and levator scapulae elevate and protract the shoulder girdle causing reciprocal weakness in the deep neck flexors and lower shoulder stabilizers. In a clinical situation, the aberrant upper crossed pattern must first be corrected before assessing and treating motion-restrictions at the sternoclavicular, acromioclavicular and internally rotated glenohumeral joints.

In extreme positions at the end range of shoulder motion, the ligaments crossing the glenohumeral joint are under increased tension. Flexion (moving the arm upward to the front) tightens the posterior capsule pushing the humeral head anteriorly. Extension (moving the upper arm down to the rear) tightens the anterior capsule pushing the humeral head posteriorly. Prolonged sitting or standing with arms working in front of the body often results in a slumped shouldered, forward head posture as seen in Vladimir Janda’s upper crossed syndrome (see Figure 2).  This commonly seen pattern causes the humeral head to internally rotate resulting in fascial adhesions, excessive mechanoreceptive stimulation and, in time, protective muscle guarding.

Of the ten or so ways the humerus can become restricted in the glenoid fossa, external rotation, internal rotation and abduction are the most problematic. Frozen shoulders typically begin with internal rotation restrictions followed by loss of external rotation and arm abduction. Assessments and corrections for painful soft tissue shoulder conditions such as rotator cuff tendinosis, bicipital tendinitis, frozen shoulder capsulitis, etc. will be addressed in future e-newsletters but for now, let’s look at muscle-energy mobilization techniques for restoring pain-free range of motion to articular capsular adhesions.

FIGURE 3. Internal, External and Abduction Restrictions (below)

	Treating Internal Rotation Restrictions With client’s right arm braced behind her back, therapist’s right hand stabilizes the acromion while his right hand grasps client’s elbow. Therapist’s right hand gently brings client’s arm to the first internal rotational barrier by pushing her elbow and resisting with the left hand. The client attempts external rotation (pushes posteriorly) with a 20% effort to a count of six and relaxes. The therapist then brings the elbow forward into more internal rotation to the next restrictive barrier and repeats the same procedure until arm is parallel to client’s body. Note: An alternative internal rotation technique was presented in last month’s acromioclavicular issue @ http://erikdalton.com/NewslettersOnline/Newsletters.htm   When using this particular glenohumeral technique, the arm must stay horizontally abducted at 90 degrees which close-packs the acromioclavicular joint.
	Treating External Rotation Restrictions With client’s arm horizontally abducted at 90 degrees, therapist’s right hand braces the acromion, arm braces the elbow, and his left hand brings client’s arm to the first external rotational barrier. Therapist resists clients attempt to internally rotate (pushing arm down) to a count of six and relaxes. Client’s forearm is then brought up to meet the new external rotation barrier and procedure is repeated until 90 degrees of pain-free external rotation is achieved.
	Treating Arm Abduction Restriction Client’s right arm rests on therapist’s left shoulder. Therapist bends knees and hands grasp the acromion. As the therapist slowly straightens his legs and braces with his hands, a counter-force is created that brings the client’s arm to the first abduction restrictive barrier. Client is asked to press down on therapist’s shoulder to a count of six and relax. Therapist again straightens legs bringing client’s arm up to the new restrictive barrier. This continues until 180 degrees of smooth, pain-free abduction is attained.