Print this page

Supraspinatus Impingement Syndrome/ RCS (Rotator Cuff syndrome)

arm therapy2

RCS is a disorder which is not exclusive to athletes who engage in overhead throwing activities, even though it is quite common among swimmers and
throwing athletes just as much as weight lifters and body builders. The common symptoms are pain in the anterior (front part) of the shoulder, usually during abduction movement (elevating the arm to the side) between 60-120 degrees and during forward flexion. None the less, pain can be aggravated also beyond these angles. pain can be felt while sleeping on the affected arm, lifting heavy objects, placing the hand behind the back (as closing a bra). The diagnosis requires a thorough understanding of the shoulder anatomical structures and kinetics.

Anatomy:

Joints: the shoulder girdle is comprised of 3 main articulating joints:

  1. the gleno-humeral joint: the joint between the humerus (the arm) and the glenoid ( the lateral part of the scapula- or shoulder blade). A ball and socket shaped joint. Enables multi directional movement of the arm.
  2. The ACJ- acromio-clavicular joint. Situated above the gleno-humeral joint and articulates the clavicle and the acromion which is a part of the scapula. Allows for a rotation movement of the clavicle.
  3. The SCJ- Sterno-clavicular joint- situated at the front of the chest and articulates the clavicle and the sternum (chest bone). The clavicle thus rotates between the ACJ and the SCJ.
  4. Not quite an articulating joint but the gliding motions of the scapula above the rib cage is sometimes referred to as a “fake” or demi joint.

Muscles: many muscles are involved in the movement of the shoulder girdle, only
the key muscles will be entailed here:

  1. The rotator cuff muscles. provide Rotational movements of the humerus within the gleno-humeral joint. Originate from the scapula and insert into the humerus. 4 in number. The suprspinatus, infraspinatus, subscapularis and teres minor. The main purpose of these muscles is to stabilize the gleno-humral joint actively and provide movement with stability so that the more powerful and superficial muscles (as will be entailed later) that provide most of the gross force, will not dislocate the shoulder or cause excessive and unchecked movements within the GHJ. As if to keep a hinged door in place.
  2. The Deltoid: a delta shaped, large external and suerpficial muscle that originate from the scapula and inserts into the humerus. Its function has more of a gross movement and power and less of a stabilizing nature. The rotator cuff muscles pass underneath it. If a hinged door example was given earlier where the rotator cuff's function is to stabilize the hinge, the purpose of the deltoid is to provide the strength to move the door.
  3. scapular muscles: this group of muscles include the lower and middle trapezius muscles/ the originate from the spine and insert into the scapula. In addition to those, important muscle as the serratus anterior should be mentioned as well. Originate from the rib cage and inserts into the scapula. The rhomoboids muscles that attach the spine to the scapula. This group of muscles' main function is to stabilize the scapula with regards to the spine and rib cage (while the rotator cuff muscles for example stabilize the humerus with regards to the scapula).
  4. The back extensors: a group of muscles passing along the spine. They originate from the pelvis and from the spine itself and insert to the upper part of the spine and to the ribs. Their main function is to extend the back while the shoulder is moving, thus allowing it to reach the end rang of motion. Without proper back extension provided by these muscles, the forward flexion of the arm will be limited only to 135 degrees.
  5. The biceps brachilais: originate at the scapula and inserts into the radius in the forearm Its main function is flexion of the arm and elbow. Its long tendon passes inside the shoulder joint and irritation of its tendon might show signs, similar to a rotator cuff tear disorder.

Nerves:

The peripheral nervous system originates at the nerve roots at the spinal cord. From there it passes through the intervertebral foramina (between the vertebras), through the scaleni muscle at the front of the neck, underneath the clavicle and through the pectoralis minor muscle in the chest. From there is descends down to the upper limb, innervating motor and sensory functions. It is important to mention this system because disturbances to it might result in symptoms around the shoulder itself, just as much as hinder functional movement of the shoulder due to lack of sensory or motor control.

Shoulder movement:

In order to execute a well balanced movement in the shoulder the upper back has to be mobile and all other muscles should contract at the right timing.

  1. Deep muscles like the rotator cuff muscles start the movement in the gleno-humeral joint and balance the head of the humerus inside the Glenoid cavity throughout the movement.
  2. Strong external muscles like the deltoid, the pectoral muscles and the latissimus dorsi provide the strength to the movement.
  3. Scapular muscles that attach the scapula to the rib cage (serratus anterior) and to the spine (the trapezius muscles and rhomboids), balance and control the movement of the scapula throughout the movement.
  4. The back extensor muscles provide for spinal extension that is required in over head movements above 135 degrees.
  5. Even the abdominal oblique muscles stabilize the rib cage throughout the movement.

All of these muscles should contract at the right timing while being innervated by the peripheral nervous system. Failing to do so will result in an unbalanced movement where some muscles work harder that they should and fulfill more than their purpose. e.g muscles with more of a Stabilizing function will act as both stabilizers and prime movers and vice versa. This can be caused due to weakness, faulty movement patterns caused by past traumas, pain avoidance behavior, poor innervation by the nervous system, lack of articular range of motion etc.

influencing factors:

  1. muscle weakness: a lack of ability by the rotator cuff muscles to balance the head of the humerus will result in migrations and translations inside the gleno-humeral joint that might end up in tendon impingements and strain on capsular ligaments. Weakness in scapular muscles will result in unbalanced scapular movement which means that the “socket” in the “ball and ” GHJ joint will be positioned poorly and endanger the structures situated within it . Also, the rotator cuff muscles that originate from the scapula will contract from a faulty position, thus working in overload or a non functional way.
  2. Articular range of motion limitation in the gleno-humeral joint, spinal joints, Shortening of muscles that may result in a decreased range of motion. The decreased ROM will force the muscles to contract harder beyond their ability. Not to mention the the decreased ROM already limit the ability
    of these muscles to contract. The decreased ROM will also decrease the space requires for tissues to move, which again might end up in impingements, friction syndromes etc.
  3. Past trauma:. People that suffered a shoulder dislocation or subluxation in the past may suffer consequently from an Instability or lack of control in the rest of the upper limb muscles. strength in these muscles is not enough. The ability of the nervous system to control the activity and timing of contraction of these muscles is just as important. There’s a vast system of sensors situated in muscles, tendons, joint capsules and even the skin that send signals associated with stretch, tension, muscle contraction respectively to the brain. The brain processes all of these sensory signals and develops an image of how the movement is carried out. If this system of sensors is damaged by a trauma such as a dislocation, fracture, lack of training or just negligence, consequently the movement image in the brain wouldn't be presented properly. Therefore, over use of muscles, unbalanced contractions can occur and lead to an overload on more distal structures in theshoulder, elbow and wrist. This system is also known as the proprioceptive system and its sensors- the propriosensors.
  4. Poor nerve innervation: the nervous system can be disturbed by an external factor such as a prolapsed disc at the spinal level, a tight Scaleni or Pectoralis minor muscles or be compressed by the clavicle against the 1st rib. These disturbances can cause a direct referred pain down the upper
    limb, manifested as shoulder pain or pain in the rest of the upper limb, elbow pain, sensations resembling as electric current passing down the arm, pins and needles sensations, lack of sensation or hyper sensitization etc. Or on the other hand these disturbances can interrupt the motor and sensory input and output and lead to uncontrolled movement patterns. As if an optic fibre is being pressed by an external force and cause disturbances in the transmission
  5. skeletal deformities: there are researches that link the shape of the Acromion to the impingement of the rotator cuff tendons. A hooked shaped acromion will decrease the sub-acromial space where the supraspinatus tendon passes and might cause an erosion, friction, impingement and eventually to an inflammation and tears in the tendon. Scoliosis deformities at the spine might also place the scapula in a non optimal position.

Treatment:

  1. Stop strained physical activity, especially one which is associated with overhead activities as lifting and throwing, swimming.
  2. Pain control technics as massage, ice, electrotherapy, ultrasound
  3. mobilization of joints in the shoulder and upper back.
    shoulder treatment
  4. Strengthening the weak components in the kinetic chain according to the outcome of the evaluation (rotator cuff muscles, scapular muscles etc.)
  5. taping: kinesio and athletic taping technics help to decrease pain, increase proprioception, inhibit overloaded muscles or on the other hand facilitate functional movements.
    shoulder kinesiotaping
  6. Dry needling: overloaded muscles might cause trigger points which are inner contraction points or nodules within the muscle fibers. These nodules stay contracted passively and limit the ability of the muscle to either generate a functional contraction or stretch (thus even limiting the range of motion). These trigger points might refer pain themselves to other areas that might present symptoms. The dry needling technique (that can be read in “types of treatment” page) release those trigger points instantly, thus restoring functional contraction, muscle length and ROM.
    dry needling shoulder
  7. Nerve dynamics: if the peripheral nervous system is affected, stretching and mobilizing the nerve after releasing the compression by the external factor, will help nerve innervation, nerve vascularization (blood supply) and motor and sensory input and output to the central nervous system.
    nerve dynamics shoulder
  8. Improve proprioception: if propriosensors are damaged after a trauma or due to inactivity, they can be trained in a variety of exercises.
    Researches have shown that 50% of the population around the age of 50 and 70% of the population around the ages of 70-80, clinically present a tear in the rotator cuff tendon. The interesting thing is that there is no correlation between the existence of a tear to the existence of symptoms. Some people walk around with a rotator cuff tear without their knowledge. This means that MRI, CT, ultrasound results do not necessarily determine the cause of the problem. These research results determine to a great deal the necessity of a thorough clinical evaluation that checks all of the above mentioned elements in order to get down to the bottom of the cause of the faulty movement pattern and the symptoms themselves. In short- find out the “why” and “how” and not just the “what”. This article hopefully will emphasize the necessity of a supporting training regime in addition to the actual sport one may be practicing.

***This article mentions several methods of evaluation and treatment. These are merely guidelines. They are not an independent treatment program nor intended to replace a thorough evaluation and treatment program executed by a certified physiotherapist. Its advised to undergo such evaluation and treatment by a certified physiotherapist if such injury occurs and act upon their professional judgement call***