Background and Etiology
The rotator cuff complex includes the tendons of four muscles at the shoulder: supraspinatous, infraspinatous, teres minor and subscapularis. All four of these muscles originate at the scapula (shoulder blade) with their tendons passing through the subacromial space to insert on the greater tuberosity of the humerus.
The subacromial space is comprised of the acromio-clavicular joint, coraco-acromial ligament and acromion (outer edge of the scapula). This is called the coracoacromial arch. Narrowing of this space can set up an environment where the rotator cuff muscles are compromised, resulting in an impingement (pinching), fraying and eventual tearing of one of the tendons.
The functions of the rotator cuff include
- Rotation of the humeral head and shoulder
- Stabilization of the humeral head in the glenoid socket by compressing the round head of the of the humerus into the shallow socket (referred to as a cup or an even flatter saucer) of the glenoid fossa of the scapula
- Providing “muscular balance” by stabilizing the gleno-humeral (shoulder) joint when other large muscles, including the deltoid, contract.
- Assist in the elevation or raising of the arm
One cause of a rotator cuff tear is trauma or a fall onto the shoulder or outstretched arm. This is more common in the older population where the circulation of the tendons is reduced and the tendons are more susceptible to injury. Repeated overuse, especially with activities that require over the head motions, like throwing, can also cause a rotator cuff tear. Bony Spurs, advanced impingement or degeneration resulting in fraying of the tendon may also progress to a tear.
- Depending on the severity of the tear, the pain associated with a rotator cuff injury may be mild, moderate, significant or nonexistent. Many times complete tears of the rotator cuff muscles may be pain free because the tendon (the origin of the pain) is completely torn and thus not being irritated in the subacromial space. Otherwise, pain may be manifested as achiness at the tip and front of the shoulder that can radiate down the lateral arm. This may include a painful arc of motion between 60-120 degrees of motion when performing overhead activities. Pain may also be present with overhead activities, lifting, throwing motions and reaching across the body.
- Difficulty sleeping on the effected side and performing daily activities such as dressing, putting on a coat, fastening a bra or combing your hair.
- Restricted range of motion of the shoulder that makes reaching for items, overhead activities or reaching behind the back more difficult.
- Weakness or decreased ability to initiate movement or raise the arm over the head (flexion) or away from body (abduction). It can become difficult to raise the arm overhead independently or even with assistance.
- Atrophy or wasting of the infraspinatous or supraspinatous muscle bellies located below and above the spine of the scapula (shoulder blade) may be present.
- When actively raising the effected arm, the patient may substitute by hiking or shrugging their shoulder to get the arm up.
Stages of Rotator Cuff Tears
Stage 1: Edema and Inflammation, or early stage impingement characterized by pain with certain positions and motions. Overhead motion restrictions and performing over the head activities may be difficult.
Stage 2: Fibrosis and tendonitis characterized by marked loss of motion, pain, weakness, inflammation and tendon involvement. Actively lifting the arm overhead independently and sometimes with assistance may become difficult. Joint noise, grinding “crepitus” and a feeling of catching when raising the arm over head may be present.
Stage 3: Bony Spurs and tendon ruptures with significant weakness, degenerative changes, decrease or absence of active motion, significant or absence of pain depending on the severity of the damage may occur.
Classification of Rotator Cuff Tears
- Acute versus chronic based on time since injury
- Partial versus complete
- Partial are on the articular (joint) or bursal side of the tendon
- Complete based on the depth of the tear
Size of tears
- Small (0-1 cm²)
- Medium (1-3 cm²)
- Large (3-5 cm²)
- Massive (> 5 cm²)
The stage and classification of a person’s injury, along with the person’s values and their health care professional’s experience all play a role in determining a course of treatment for a rotator cuff tear.
For less severe injuries a conservative approach that includes physical therapy may be attempted. However, significant or complete rotator cuff tears will require surgical intervention to decrease pain, improve range of motion and improve function. Small, incomplete tears may respond to conservative physical therapy depending on the patient’s age, level of expected activity and functional level. Small tears requiring surgery may only require arthroscopic decompression and therapy. Medium to massive tears will more likely need open repairs, longer healing times, and extensive physical therapy.
Physical therapists are professionals, educated and trained in administering interventions. As stated in The Guide to Physical Therapist Practice, interventions are the skilled and purposeful use of physical therapy methods and techniques to produce changes consistent with the diagnosis, prognosis and the goals of the patient or client.
Interventions for the rotator cuff need to be progressed according to the healing and physician surgical protocol in the case of postoperative repairs. Common interventions in the treatment of a Rotator Cuff tear include:
- Manual Therapeutic Technique (MTT): hands on care by a physical therapist to regain mobility and range of motion in the shoulder and surrounding joints.
- Therapeutic Exercises (TE) to gain range of motion and strengthen the shoulder and surrounding joints. Rotator cuff strengthening exercises to dynamically depress and stabilize the humeral head result in improved biomechanics that can restore muscle function and eliminate substitution for shoulder elevation and over head activities
- Neuromuscular Reeducation (NMR) to begin retraining the upper extremity and the person overall to use the involved upper extremity in daily activities. Scapula stabilizing exercises may be used because the scapula is the base of support for the rotator cuff muscles.
- Modalities including the use of ultrasound, electrical stimulation, ice, cold laser and others to decrease pain at the shoulder.
- Home program including strengthening and stretching exercises and instructions to help the person with the rotator cuff injury perform daily tasks and advance to the next functional level.
Several factors affect the rehabilitation after rotator cuff repair.
Type of repair
- Open: this may involve the detachment of the deltoid. This requires no active deltoid contraction for 6-8 weeks to prevent deltoid avulsion (pulling from the bone).
- Mini-open: may involve a vertical split along the deltoid fibers. This allows for early, but low intensity deltoid contractions.
- Arthroscopic: a “scope” is used to perform this procedure. Fixation may not be as secure as the first two options, thus leading to a slower rate of rehabilitation.
Size of tear
- Larger tears require longer time to allow for healing of the tissue, thus delaying the introduction of strengthening exercises and limiting range of motion for specific periods of time based upon the directives of the orthopedic surgeon who performed the surgery.
Quality of the tissue
- Quality of the tendon, muscle, and bone will determine the rate of progression within rehabilitation. The orthopedic surgeon will take note if the qualities of the tissue include thinner, fatty or weak tissue that will need to be progressed slowly. Tissue may be graded as being good, fair or poor quality.
Location of the tear
- Slower progression in external rotation will be required when posterior cuff structures are involved in the repair. Surgical repair of the subscapularis along the anterior shoulder will require restrictions with internal rotation during the early stages of rehabilitation. Most rotator cuff tears will occur at the supraspinatous tendon that corresponds to a subacromial impingement.
Onset of the tear and timing of the repair
- Acute tears with early repair may become stiffer than when the surgery is delayed. This will require a very consistent approach to gain range of motion in the shoulder. However, early repair generally leads to rapid progress through rehabilitation.
Depend on several patient variables:
- Outcomes are better for the younger patients rather than older patients
- Dominant versus non-dominant upper extremity has been reported not to have a significant effect on outcome from rotator cuff repair
- Pre-injury level of function with a positive correlation between pre-surgery shoulder function and post-surgical outcomes (the better you are before you sustain an injury, the better the chance for a good outcome post-surgery)
- Motivation of the patient to return to activities like work or sports
- Patient compliance with physical therapy program is critical to a good outcome from rotator cuff repair.
- Evidence based practice (EBP) approach to rehabilitation
- EBP involves having the post rotator cuff repair rehabilitation plan of care developed and implemented by a physical therapist informed on the most current scientific and medical evidence regarding rotator cuff repair rehabilitation. The therapist must incorporate this information, with the particular patient’s desires and the physical therapists experience, to guide the patient to positive outcomes as quickly as possible.
Reference: Brotzman SB, Wilk KE. Clinical Orthopaedic Rehabilitation. 2003, Mosby, Philadelphia, PA.