Rotator Cuff Tendinopathy

Reasons muscles are weak: Disuse, tensile overload, suprascapular nerve impingement

Suprascapular nerve C5-6: runs underneath the suprascapular ligament (the bridge) in the suprascapular notch. Innervates supraspinatus and infraspinatus (weakness if injured).

Reasons for RCT:

Motor control issues causing overuse - Scapular dyskinesia and RC Tendinopathy

Hypermobility- Multi-Directional (AMBRI), Uni-Directional (TUBS), AC sprain, Fractures, Slap tears

Hypomobility- Adhesive Capsulitis, Osteoarthritis, Joint Arthroplasty

Causes of impingement: Muscle weakness, tightness, motor control, anatomy of RC, shape of acromion, capsular stiffness, postural.

Summary of Phadke article:

Scapula: decrease in upward rotation, decrease in posterior tilting, increase in internal rotation.

Clavicle: increase in elevation, increase in retraction.

Humerus: increase in anterior and superior humeral head translation in the fossa.

Subacromial space sparing movement: shoulder elevation (compensatory movement)

Force couples:

supraspinatus and deltoid for superior roll and inferior glide.

upper/lower trap and serratus anterior

Scapular Force Couples:

Lower Trap: causes more retraction in shoulder abduction than flexion (assists with upward rotation)

Upper Trap: Clavicular Elevation

Serratus Anterior: can create posterior tilt and upward rotation especially when scapula is beginning to upwardly rotate. (weakness causes inferior angle to move medially)

Trapezius weakness causes inferior angle to move laterally

If patient has shoulder pain, DO NOT TRAIN THE UPPER TRAP IN ISOLATION

Changes from the normal pattern of muscle activity with shoulder impingement:

Upper Trap: increase in activity (40-100*)

Serratus Anterior: decrease in activity (30-120*)

Lower Trapezius: increase activity (60-120*)

Why might patients have pain during early shoulder elevation?

Supraspinatus, infraspinatus, and subscapularis all have decrease in activation; decrease in rolling and inferior glide.

Increase in mid deltoid activity from 0-60*

Between 90-120* there is more normal co-activation of the RC and deltoid (less superior force of the deltoid).

Scapular Dyskinesis (timing):

Refer to scapulohumeral rhythm, ratio should be 2:1, capsular tightness= increase resistance causes scapula to move quicker in the ROM

Primary Impingement Vs. Secondary Impingement:

Primary: structural problems

Secondary: Due to instability of the GH joint, problems with timing of muscle activation, impingement of subacromial space.

Subacromial, external, anterior impingement all mean the same thing

60% of partial thickness tears occur at the articular surface, only 7/62 had any pathology to the bursa.

Posterior Impingement: test includes pushing scapula into full ER and is positive if pain decreases (lay them down and push on the coracoid and then do ER, pain should decrease)

Occurs with supra/infra being impinged between glenoid/greater tubercle (this position is VERY different than the anterior impingement position). Impingement with 90* abduction and full ER.

Painful Arc Test: Lift arms above head, pain at mid range then pain goes away=positive. (pain can be anywhere for it to be positive. Pain needs to happen then go away for it to be positive).

Neers Test: Passive test, therapist is doing the work. Positioning the arm in a way to try and cause mechanical pain. Can do test standing or seated. Start with good posture, hand should be externally rotated with other hand on scapula, lift them up into full flexion “does that hurt yes or no”, next internally rotate the arm and lift the arm up “does it hurt” → is that your pain, where is it. Pain should happen with internal rotation and elevation because there is impingement.

Hawkins Kennedy Test: Assessing for subacromial impingement. Bring arm up to 90*, internally rotate, horizontally adduct to 90*, depress the scapula, if no pain bring them into more horizontal adduction. Positive test is when pain occurs.

Typical Posture of patient with impingement: forward shoulders, muscle imbalances, these are referred to as upper cross syndrome

Structures causing anterior impingement “critical zone”: roof is acromion and coracoacromial ligament, the floor is the humeral head. Contents include coracohumeral lig, superior glenohumeral lig, bicep tendon long head, supraspinatus, subscapularis superior portion.

Type 1 acromion: flat

Type 2 acromion: smooth/curved

Type 3: anterior hook

Rotator Interval: The space between the subscapularis tendon and the infraspinatus tendon. Suprispinatus, biceps tendon, coracohumeral lig, superior glenohumeral lig, subscap.

Rotator Cable: CHL connects infraspinatus and Subscapularis

Acute tear: Surgery is a good outcome for those who are older, as long as the tendon is in good health otherwise. AGE IS MAIN FACTOR FOR SURGICAL CANDIDATION

Anatomical relationship between CHL and supraspinatus: Helps create a sling/cable with infraspinatus and subscapularis.

Goal of acromial decompression (osteotomy): conserve Coracoacromial lig but remove underneath of the acromion to increase space for the critical zone contents.

Obligatory translation: if the humeral head cant glide inferiorly and posteriorly, it will slide out.

Central Sensitization: neuroplasticity within the CNS

External Rotation Lag Sign: Pull into ER, if there is rebound it is positive. From this test go right into MMT of infraspinatus. The lag might mean a progression of the tendinopathy.

Reverse Impingement: provide inferior glide (in supine or seated depending on how early they are getting symptoms, 100* or less do it in seated, if symptoms are closer to 180* do it in supine to facilitate proper movement mechanics and alleviate symptoms. This technique aims to enhance the subacromial space and reduce friction during shoulder elevation.

Roos Test: Hands up to side and clench fists over and over, reproduction of symptoms

Lift off sign: subscap

Belly Test: subscap, watch the elbow going in

Drop Arm:

Empty/full can:

Hornblowers: arms up above the head, push elbows into internal rotation and have them push into external, this is indicative of teres minor and some infraspinatus

Shoulder Symptom Modification Procedure:

Identify aggravating symptoms, alter posture, reposition scapula starting position, apply inferior glide to humerus, look for a reduction in symptoms of at least 30%.

Bicipital Tendinitis: secondary to impingement, occurs directly during overhead movement with laxity of the transverse ligament.

Speeds Test:

Yergasons Test:

Bursitis: looks like tendinitis, decrease in ROM with anterior and lateral shoulder, decrease A and PROM noncapsular pattern with pain. Painful arc, pain with mmt, pain with palpation, +impingement and empty can test, the biggest indicator here is inflammation.