Shoulder pain is the most commonly presented shoulder complaint. Causes of Shoulder Pain
- Intrinsic – Caused by the structures in the shoulder
- Extrinsic – Caused by pathology outside the shoulder with the pain referred to the shoulder from another epicenter
Intrinsic Causes include Mechanical pain which occur with active motion. Most common cases of shoulder pain includes:
- Tendon disorders which bring on limited motion due to pain and viable amounts of muscle weakness caused by Bursitis, Tendonitis and Rotator cuff tears
Non-mechanical pain occurs at rest without use of the shoulder caused by:
- Nerve compressions syndromes
- Inflammatory conditions
- Tumors about the shoulder
All of these conditions present with a physical finding called impingement. Impingement Syndrome is pain elicited in the shoulder when the shoulder is elevated between 90Â°-120Â° overhead. It is not a diagnosis but simply a physical finding that has many causes.
Bursitis is the inflammation of the bursa (tendon lining) in the shoulder. The shoulder bursa is a cellular layer forming a sac lying under the shoulder blade roof. It produces a limited amount of synovial fluid. The synovial fluid acts to reduce friction during joint motion allowing for smooth tendon gliding.
When the bursa is inflamed due to injury or repetitive overhead activities, the bursa over secretes the synovial fluid. The fluid thickens and results in shoulder impingement pain. Shoulder tendonitis is when the tendon proper of the rotator cuff is inflamed.
Rotator Cuff Tear Causes
Intrinsic – The rotator cuff tendon bends at a sharp angle prior to inserting (attaching) onto the humeral tuberosity footprint, thus creating a differential pressure on the various tendon layers of the shoulder. A decreased blood supply to the tendon as we age is another cause.
Extrinsic – Acromial bone spurs form in the anterior and inferior part of the acromial undersurface with aging. This consequently scrapes away the tendon as we perform overhead activities until a rotator cuff tear develops.
Classifying Bone Spurs
- Type I- flat
- Type II- curved
- Type III- hooked
Types II and III are larger spurs and are believed to be the ones to cause the abrasion on the rotator cuff tendon resulting in a rotator cuff tear. With rotator cuff tears, impingement pain is usually accompanied by variable amounts of rotator cuff weakness on a physical exam.
Type I Type II Type III
Classification of Rotator Cuff Tears depends on whether the five layers making up the tendon thickness are partially torn, or completely torn.
Partial can be further classified by location of tear:
- Bursal sided tear: on the top of tendon
- PASTA lesion (Partial Articular Supraspinatus Tendon Avulsion): tear on the joint of the tendon
Complete tear are when the tendon fibers are torn from bursal subacromial side and communicates with the joint side, allowing joint fluid to escape.Further classified by size of tear:
- Small (<1cm)
- Medium (1.1-3.0 cm)
- Large (3.1-5.0 cm)
- Massive (>5.0cms)
The larger the tear, the more associated weakness is found on a physical exam and the higher the probability of recurrence after a repair. This is why it’s recommended to repair a complete tear before it gets larger.
10 Things to Know About Rotator Cuff Tears (RCT)
1. RCT do not heal on their own. Surgery is required for healing.
2. RCT will increase in size over time. The rate of progression is unknown.
3. It is rare for a person less than 40 years old to incur an RCT without a prior significant injury.
4. The incidence of RCT increase with age, starting at 40 years of age and are present in about 50% of people after the age of 60 years.
5. The presence of an RCT does not necessarily mean symptoms will also be present.
6. The larger the RCT, the more likely a tear will recur over time after a repair. Lifting discretions are permanently advised after repairing a large or massive tear.
7. If a massive RCT separates from its attachment site and retracts, the muscle will begin to atrophy. If left unrepaired for six months, a successful repair is less likely.
8. RCT repairs can be performed with open or arthroscopic techniques depending on the training and experience of the surgeon.
9. After a RCT is repaired, the healing time and the return of good functionality depends on:
- Size of the tear
- Quality of the tendon
- Bone density where the suture anchors are placed (greater tuberosity footprint)
- Age of the patient – The repaired tendon has to take root on the repair site. This takes an average of 4 months.
10. The assigned level of therapy after surgery depends on:
- Size of the tear
- Quality of the tendon
- Quality of the bone
- Amount of tension on the repair. Tension depends on how long a cuff tear was retracted prior to being repaired
If pain is felt during exercises after a rotator cuff repair, it is an indication the therapy is too aggressive and the exercises should be curtailed.
The biceps muscle has two tendons of origin. One begins on the very top of the glenoid and the other originates on the coracoid bone of the shoulder blade (shown above). The biceps muscle serves to bend the elbow and rotate the forearm in a palm up position.
Long Head of the Biceps Tendon
- Comes off the glenoid bone/labral junction
- Common site of a biceps tendon rupture
- Occurs with increasing age/activity and Minor exertion
The long head tendon travels through the humeral groove, and is constantly having the humeral bone slide past it back and forth with arm motion. In time, depending on the shape of the groove, the tendon wears away and partially tears until a complete rupture is experienced.
Symptoms of a Torn Long Head Bicep Tendon Tear consist of first a sudden pop in the shoulder is felt, followed by:
- Discoloration of the upper arm
- Muscle spasms of the upper arm
- Appearance of a bulge in the mid arm called a œpopeye muscle
Because there are two tendon origins of the biceps muscle, the lack of the long head of the biceps rarely causes a functional deficit and repair is not normally recommended.