Sunday, April 1, 2012

Rotator Cuff Tears
By Ryan Smart, MD
Syracuse Orthopedic Specialists

Rotator cuff tears are among the most commonly encountered disorders of the shoulder.  They can be debilitating and difficult to treat.  Chronic rotator cuff tears are common and with the aging population the incidence of new tears continues to rise.  More than 50% of individuals older than 60 years have at least a partial rotator cuff tear and full thickness tears are found in almost half of individuals older than 80 years. (1)  Approximately two-thirds of all rotator cuff tears in the general population are asymptomatic and factors found to be associated with symptoms when one has a rotator cuff tear are a positive impingement sign, weakness in external rotation, and presence of a tear in the dominant arm. (2)  Procedures done to treat rotator cuff disease are among the most common of all orthopaedic surgeries.

The glenohumeral joint has very little bony support.  The rotator cuff, which is made up of four muscles (subscapularis, supraspinatus, infraspinatus, and teres minor), plays a major role in both the mobility and stability of the shoulder.  Of these two roles, stability appears to be the larger function.  To maintain a ball-and-socket articulation during motion, the humeral head is compressed into the glenoid socket by the rotator cuff.  Without such compression, the humeral head can undergo excessive translation within the socket which disrupts shoulder kinematics.  EMG studies have shown that the rotator cuff muscles fire prior to and then concurrently with the deltoid and pectoralis major muscles.(3)  This preceding and concurrent activation of the rotator cuff muscles maintains the shoulder joint for dynamic stability during larger muscle contractions.
Pain is the most frequent complaint.  It can at times radiate down the arm to the level of the elbow.  Many patients will complain of nighttime pain.  Typically, the pain will be worse with certain motions such a forward elevation or abduction.  As the tear progresses, weakness will become a more prevalent symptom.  Rotator cuff pain does not typically radiate down the arm to the level of the wrist or hand.  If such symptoms are present one should suspect the cervical spine as the pain generator.  A history of a trauma or fall will sometimes be present but many times patients cannot recall a specific inciting event.
Physical Exam
A thorough physical exam significantly aids in the diagnosis and management of rotator cuff tears.  A complete shoulder exam should be performed starting with inspection and palpation.  Range of motion is then assessed both passively and actively.  If both passive and active motion is limited one should consider an alternative diagnosis such as adhesive capsulitis (ie frozen shoulder).  Patients with rotator cuff pathology will typically have mid-arc pain.  A positive Neer and Hawkins maneuver is common.  Strength testing is performed for each rotator cuff muscle.  The empty can and drop arm maneuvers test the supraspinatus.  The lift-off, belly press and bear hug all test the subscapularis and external rotation strength tests the infraspinatus and teres minor.  The combination of a positive drop-arm sign, painful arc sign, and infraspinatus muscle strength test was most predictive for full thickness rotator cuff tears.(4)
Nonsurgical management is typically the first line of treatment for most rotator cuff pathology.  The natural history of rotator cuff tears is thought to be that of tear progression. (5)  It is believed that tear size progression is a factor in the development of symptoms.  Physical therapy and shoulder rehabilitation should focus on restoration of motion, flexibility and strength. (6)  Nonsurgical management may also include pain medication and anti-inflammatory drugs and subacromial cortisone injections.  Although injections are common a recent systematic review suggests that long-term benefits are limited. (7)  Multiple cortisone injection should be avoided in patients who may be best served with surgical intervention.  Successful non-operative management has been correlated with symptom duration of less than 3 months.  Factors that have been found to predict failure of conservative treatment are: 1) full-thickness tear greater than 1cm x 1cm, symptoms present for more than 1 year, and functional impairment and weakness. (8)  Nonsurgical treatment is often attempted for a minimum of 6 to 12 weeks before surgery is considered.
When patients fail conservative treatment surgery is usually indicated.  Tears can be repaired either arthroscopically or by open means.  The clinical results reported with arthroscopic repairs are equivalent to those reported for both open and mini-open. (9,10)  However, the deltoid muscle is undisturbed with arthroscopic repairs thus making it the favored approach by many.  The goal of surgery is to anatomically repair the rotator cuff securely to bone with as little tension as possible.   Reported healing rates, based on ultrasound and MRI, range from 91% in small tears to 10% in massive tears. (11)  With larger tears, the best clinical results are achieved in patients who experience tendon healing postoperatively. (12)

The ideal rehabilitation program allows for tendon to bone healing and prevents stiffness.  Most agree the best clinical results occur when the rotator cuff heals to bone in its entirety.  Since the rotator cuff heals very slowly (~5% per week) most have adopted fairly conservative rehab protocols limiting motion the first 6 weeks.

Dr. L. Ryan Smart specializes in sports medicine, arthroscopic surgery, and shoulder surgery.  He completed his fellowship in sports medicine at the New England Baptist Hospital in Boston, MA and completed his orthopaedic surgery residency at Yale in New Haven, CT.   After completing his undergraduate studies at Cornell University, he went on to the University of Michigan for medical school.  He is the team physician for the Christian Brothers Academy football team, Cornell Men’s Ice Hockey, Syracuse Silver Nights soccer club and Fayetteville-Manlius High School. He played 4 years of varsity ice hockey at Cornell and was drafted by the New Jersey Devils in the 1994 NHL entry draft.  His professional memberships include Arthroscopy Association of North America and the American Orthopaedic Society for Sports Medicine.

1 comment:

  1. This is such a full of information. To have this kind of condition is not that easy to handle, it can produce so much pain. Thank you for sharing.