Rotator
Cuff Tendinitis
(also
see 4 Exercises to Avoid
and What Goes
Wrong)
Definition & Background
The central role the rotator cuff has in shoulder function
almost precludes its involvement in most painful disorders of
this joint. Rotator
cuff tendinitis (RCT) refers to micro-tearing or inflammation
of one or more of the four rotator cuff tendons of the shoulder
(Supraspinatus, Infraspinatus, Teres minor,
and Subscapularis, or SITS). Commonly referred to as impingement syndrome,
RCT can be primary bursitis, impingement from mechanical abutment,
or secondary from glenohumeral instability.
RCT is common in those who are 25 to 40 years, when tendinitis
and fibrosis are found to be most frequent and chronic. After 40 years, there is full-thickness rotator cuff tearing, requiring
operative repair. This
age-related characterization of RCT is accelerated in athletes
involved in sports with repetitive overhead motions, who not
only increase the forces on the cuff tendons, but also the repetitions
of aggravating motions.
Signs
& Symptoms/Muscle Testing
Patients usually present with pain of insidious onset
exacerbated with overhead activities.
The pain is usually in the anterior deltoid, but it can
be referred anywhere on the deltoid and down the mid-arm.
The pain is often felt at night and can awaken patients
from sleep. Later, pain may occur when the arm is moved forward to shake hands.
Usually, pain will be elicited by pushing things away,
with little or no pain on pulling objects in.
On palpation, the patient will complain of tenderness
in relationship to the irritated structure.
Their will usually be tenderness at the superior aspect
of the greater tubercle and over associated tendons, especially
when the arm is raised above the shoulder, but less common when
the arm is held by the side.
Palpation anterior and inferior to the acromioclavicular
joint and coracoacromial ligament are usually tender.
Possible atrophy may also be evident in the supraspinatus
and infraspinatus fossae.
A painful arc may be evident between 50 and 120 degrees
of abduction Severe
pain is caused by adduction of the arm across the chest.
Shoulder abduction will be weak, usually due to underuse
atrophy of the deltoid. Three
specific muscle tests are performed to assess possible involvement
of individual muscles. To examine anterior, subscapularis involvement,
pain may be reproduced by having the patient resist internal
rotation, or by performing the “lift-off” test as described
by Gerber (1990) which may be more reliable.
Posterior involvement is tested by determining strength
with thumb-down abduction at 70 degrees in the scapular plane
and by testing external rotation strength at side.
Weakness with thumb-down elevation is more specific for
supraspinatus involvement, whereas loss of external rotation
strength at side is more indicative of infraspinatus and teres
minor.
Causes
& Involved Tissues
Many factors have been implicated in RCT, including extrinsic
and intrinsic factors.
Whether a primary factor or secondary effect, RCT is thought
to be an ongoing cause of tendon injury. The supraspinatus insertion on the greater
tuberosity must repeatedly pass under the coracoacromial arch
when the arm is used in overhead activity.
The rotator cuff (S.I.T.S muscles) passes between the
coracoacromial arch above and humeral head below.
Comprised of the anterior acromion and coracoacromial
ligament, any abnormality of the coracoacromial arch, such as
an acromial spur, or ligament thickening, can encroach on the
cuff below altering cuff function.
The clash of the humerus head against the coracoacromial
arch and the pressure on the surrounding soft tissues result
in damage to the rotator cuff tendons; this also leads to an
inflammatory reaction characteristic of RCT.
There is an area of relative avascularity on the supraspinatus
muscle tendon near its insertion (tenoperiosteal junction) on
the greater tubercle of the humerus.
This region is called the critical zone
of the rotator cuff. The anatomical position of the rotator cuff
tendons plays an important role in the development of the critical
zone because it exposes the tendons to constant pressure from
the humeral head, squeezing blood out of the surrounding blood
vessels even when the arm is stationary in a position of abduction
or neutral rotation.
RCT may also originate from the weak external rotators
of the shoulder, infraspinatus and teres minor muscles.
An existing weakness of the external rotators and adaptively
shortened internal rotators of the shoulder results in an inadequate
fixation of the humeral head in the glenoid fossa in the superior
direction. This significantly increases the pressure of
the humeral head on the tendon blood vessels of the shoulder
joint’s rotator cuff. This
leads to an increasingly greater degeneration of the critical
zone accompanied by the progressive development of RCT.
In summary, the two principal theories, one anatomic
(decreased vascularization), the other dynamic (muscle weakness),
may both play roles in the origin of RCT.
At the same time it is quite clear that some causative
factors can synergistically combine to produce RCT.
These include os acromiale, acute trauma to the shoulder,
calcific deposits and excessive strain placed on the upper extremity
during vigorous activity. The clash of the humeral head against the acromion
causes injury to the surrounding soft tissue, the tendon of
supraspinatus, the long head of biceps brachii, and the subacromial
bursa, which results in RCT and scarred healing.
Consequently, various functions of the rotator cuff are
affected. The humeral head is not firmly fixed in the
glenoid fossa during arm motions and has a tendency to translate
in the superior direction.
Such an unstable humeral head causes pain, decreases
the range of movement possible in the shoulder joint, causes
instability of the shoulder joint, and disrupts normal flow
of synovial liquid which nourishes the joint cartilage; all
this leads to further progression of RCT, impingement and eventual
rupture of the tendons involved.
Flexibility,
Strength & Aerobic Prescription
Dysfunctional shoulder biomechanics,
brought about by repeated activity includes:
* muscle imbalance
between internal and external rotators
* adaptively shortened internal rotators
* inflamed rotator cuff muscles
To be effective, a rotator cuff
program must address all the components that contribute to dysfunctional
shoulder biomechanics, It must...
* strengthen the external rotators/abductors
* stretch the internal rotators/adductors
* stabilize the glenohumeral joint directly through training
specific to the rotator cuff
* stabilize the glenohumeral joint indirectly through
stabilization and freedom of movement of the scapulothoracic
joint
* stretch the posterior capsule
* eliminate postural/causative factors or training errors
that promoted inflammation and initiated dysfunctional
shoulder biomechanics in the first place.
The following program sequence advocated
by Curwin (1984) was found to be extremely effective in rehabilitating
patients with RCT in the late sub-acute and chronic phases:
1. static stretching
for 15 to 30 seconds repeated
3-5 times (1
cycle)
2. concentric and eccentric exercise begun with
gravity or light weight progressing
from slow
speed to moderate to high speeds
3.
static stretching as in 1.
4.
5-10 minutes of icing
Stretches
It is necessary to stretch
the internal rotators of the shoulder so the external rotators
can be properly strengthened and normal internal/external rotator
strength ratio (3:2) may be obtained.
The following internal rotators are the most relevant
muscles to be stretched: Pectoralis major, Latissimus Dorsi,
Teres Major, Subscapularis and Anterior Deltoid. Secondarily, the Biceps, Supraspinatus, Levator
Scapulae, Trapezius, Rhomboids, Scaleni and Triceps should also
be stretched due to their relationship with the shoulder girdle. However, to maintain brevity, only the most
significant muscles (internal rotators, biceps and supraspinatus)
will be discussed below. As
mentioned above each stretch should be held statically for 15-30
seconds and repeated 3-5 times with 7-14 cycles per week.
The following are all passive stretches (performed statically). If any sharp pain is felt, the muscle may become
further traumatized. For
this reason, the patients reaction should be carefully monitored
throughout each stretch from start to finish.
Most of the stretches are shown
with the help of a therapist, however, for self-stretch (SS),
they are equally effective by either holding a light weight
(2-4lbs), pulling with the other arm, or holding onto another
object (i.e. chair, pole, doorframe).
Pectoralis
Major
The position of stretch for the clavicular division is with the
shoulder abducted 90 degrees with external rotation. For SS, the patient would hold onto a door
frame in the indicated position and move the thorax slightly
forward and away from the affected arm.
The position of stretch for the sternal division is with
the arm placed at about 90 degrees abduction, then externally
rotated and pressed backward into maximum tolerated extension. SS is similar to the clavicular division.
The position of stretch for the lowest costal division is with the
patient seated or supine, the arm flexed at the shoulder while
held in external rotation.
SS is supine in the position shown holding onto a fixed
object.
Latissimus
Dorsi
The position of stretch is with the patient supine or side-lying with examiner
assisted attempts at accessing full abduction.
Teres
Major
The position of stretch is with the patient supine with the arm placed
in full abduction at the shoulder with the elbow bent to permit
controlled internal and external rotation.
The scapula is stabilized best in the supine position. SS is similar to the passive stretch with the
exception of the patient using his free
hand to maintain abduction and external rotation of the
affected arm.
Subscapularis
The position of stretch is with the patient supine with the arm abducted
to 90 degrees and external rotation.
For SS, the patient may do the same as above but with
a light weight in the hand of the arm to be stretched.
This uses gravity as assistance in pushing the weight
down against the resistance of subscapularis and the external
rotators.
Anterior
Deltoid and Biceps
The anterior deltoid and biceps are most effectively stretched by the patient
himself. These two muscles
both act to flex the arm and are best stretched simultaneously. Instruct the patient to grasp onto a bar (or
rest the wrists on top of a kitchen counter or refrigerator). Keeping the back as upright as possible, the
patient is to sink down slowly feeling for the stretch in the
biceps and front shoulder.
Supraspinatus
The supraspinatus is stretched by placing the patient’s arm behind the
back (fully internally rotated and adducted) resting the hand
on the back of the chair. The
therapist may apply slight pressure at the elbow in a medial
direction. SS is similar except the patient will use their
free hand to pull the affected arm medially behind the back.
External
Rotators
The external rotators are usually flexible enough to not need stretching.
However, if an individual needs beyond-average external
rotator flexibility the following self-applied stretch may be
useful. Bend the right
elbow, place the back of the wrist against the ribs, and rotate
the elbow forward. Gently
pull across and down. Keep
shoulder down and torso facing forward throughout the stretch.
This is only recommended for healthy shoulders.
Strengthening
To achieve the proper strength
ratio (3:2) between the internal and external rotators, the
patient must be advised not only to stretch the internal rotators
but strengthen the external rotators which are relatively weak.
Since the majority of muscles at the shoulder are internal
rotators, the small teres minor and infraspinatus are often
neglected resulting in stronger internal rotators which adaptively
shorten over time. The progressive loss of external rotation-due to adaptive shortening
of the internal rotators (or both)-is a common factor in RCT
and many rotator cuff injuries.
It is thus imperative to stretch the internal rotators,
followed by extensive external rotator resistance exercise.
Keep in mind that it is necessary to strengthen all of
the muscles of the shoulder girdle and rotator cuff to maintain
a healthy shoulder joint. However, to maintain brevity, the focus will
be towards the deltoid and more importantly (and often overlooked)
external rotators. The
deltoids are not part of the rotator cuff, but they interact
with the cuff muscles to a great extent. Weakness of the delts, particularly the rear
delt, predisposes the cuff to injury.
In rehabilitation, the resistance
exercises below should be performed (max. 3 ex.) at 10-12 reps
per exercise for a maximum of 2 sets with light weight (2-4lbs)
and 7 cycles per week. As
a preventative measure, the following exercises (max. 4 ex.)
may be performed at
10-14 reps per exercise for 2-4 sets with moderate weight (5-15lbs)
and 3-5 cycles
per week. Rest periods
are no longer than 1 minute in between sets or until normal
breathing has returned.
Note: Both
shoulders are worked one at a time even if only one shoulder
is injured. This is best to reduce the risk of future injury
to the uninjured shoulder and balancing the strength of both.
Side
Delt Flyes (lateral delts)
Hold a dumbbell in each hand, arms at your sides, palms facing in. Lift the weights out to the sides to about
shoulder level. Lower
and repeat. At the peak of the movement, the palms
should be facing down, and hands holding the dumbbells, should
be at the same height as the elbows.
Front
Delt Flyes (anterior delts)
Hold a dumbbell in each hand, arms at your sides, palms facing back.
Keeping the arms parallel, lift the dumbbells forward
to about shoulder level while slightly bending the elbows.
Lower and repeat.
Rear
Delt Flyes (posterior delts)
Holding a dumbbell in each hand, bend forward at the waist until your body
is parallel with the floor.
Your arms should be hanging in front of you.
Raise the weights up to the side to body level. Lower and repeat For optimum performance, keep elbows slightly bent and lift so
the weights end up in line with your ears. The posterior delt acts to some extent with the external rotators.
Increase the effectiveness of this exercise by promoting
cuff stability. Do so
by bringing the weights up in a slight arc.
Lying
“L” Flyes (external rotators)
This exercise puts maximum stress on the external rotators at the end
of the movement. Lie
on your right side on a supine bench.
Your right (supporting) arm should be in one of two positions:
either doubled up under your head; or extended down toward the
ground. Begin with your left arm bent 90 degrees at
the elbow, upper arm along your side, forearm down across your
chest. Hold a very light dumbbell in your left
hand, left palm facing toward your abdomen. Maintaining the 90 degree bend in your elbow, slowly lift the weight.
Lower and repeat. Reverse the position and repeat with the weight
in your right hand.
Standing
“L” Flyes (external rotators)
This exercise puts maximum stress
on the external rotators at the beginning of the movement. The Standing “L” Flyes should not be used
at the beginning stages of rehabilitation since it requires
moderate strength.
Hold a light dumbbell
in your right hand, rest your triceps on a support. Your right elbow should be bent 90 degrees. Your body should be at a diagonal to the support
as shown in. The angle
at your shoulder should be slightly less than 90 degrees. Maintaining the right angle at your elbow,
lower the dumbbell until your forearm is just below parallel
with the floor. Still
maintaining the right angle bend at your elbow, slowly raise
the weight back to the starting position.
Repeat with other arm.
Lying
Flyes (posterior delt)
Starting position is similar as the Lying “L” flyes. Begin with your left arm down across your chest.
Hold a very light dumbbell in your left hand,
left palm facing toward the bench. Maintaining a slight but constant bend in your
left elbow, slowly lift the weight until your arm is almost
pointing straight up. Resist
the tendency to roll back as you do the exercise.
Lower and repeat then reverse position and hand.
Aerobic
Activities
Aerobic exercise or that to strengthen the cardiovascular system is not
essential in the rehabilitation or management of RCT. However, various studies have found that specific muscles (primarily
those composed of slow twitch-type I fibers) repond best to
endurance type training. Blackburn
et.al (1990) showed that the posterior delt and external rotators
are rapidly fatiguing muscles and that higher repetitions (15-40)
with lighter weights was more effective in increasing hypertrophy
and eventually strength levels than lower reps and higher weights.
Due to their relative size and fiber type, the
external rotators have lower endurance levels which cause
them to fatigue quickly, often before they reach peak levels
of contraction. Exercises with higher reps may increase local
muscular endurance while increasing human growth hormone concentration
levels which ultimately results in greater muscle
growth. In essence, traditional weight training methods
for the external rotators may produce better results (in terms
of strength and endurance) if combined with higher repetitions
of the same exercises with shorter rest periods in between each
set. This type of rep/set/rest combo may incorporate
oxidative phosphorylation with increased demands from the aerobic
energy system. For this
reason, the patient may choose to be active for longer (>15min)
exercise periods.
Walking or running within their target heart rate (70% of max
(220-age)) will facilitate the aerobic energy system,
increasing circulation to other muscles and enhancing the heart’s
efficiency in any given task, including anaerobic and resistance
training.
- Also see 4
Exercises to Avoid
and What
Goes Wrong with Your Rotator Cuff
References
Baechle, Thomas (1994). Essentials of Strength Training and Conditioning.
Human Kinetics, Nebraska.
Berkow, Robert (1992). The Merck Manual of Diagnosis and Therapy. Merck Research Laboratories, N.J.
Blackburn TA. (1990) “EMG analysis
of posterior rotator cuff exercises”. J.Sports Med. 10:336
Curwin S. (1984) Tendinitis:
Its Etiology and Treatment.
Collamore Press, Lexington, MA.
Gerber C. (1990) “Isolated
ruptures of the tendon of the subscapularis muscle” J.Sports Med. 14:261
Horrigan, J., Robinson,
J. (1991) The 7-Minute Rotator
Cuff Solution. Health
for Life, LA, CA.
Kisner, C., Colby,
LA. (1985) Therapeutic Exercise: Foundations and Techniques. 2nd Ed. F.A. Davis. PH.
Kendall, FP., Proverance,
P. (1993) Muscles: Testing and Function. 4th Ed. Williams & Wilkins.
PH.
Magee, D. (1992) Orthopedic
Physical Assessment. 2nd
Ed. W.B. Saunders Company.
PH
Souza, T. (1994) Sports
Injuries of the Shoulder: Conservative Management. Churchill Livingstone, London.
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D. (1983) Myofascial Pain and
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