Rotator Cuff Arthropathy
Motion thru the glenohumeral joint (ball and socket) is accomplished by a fine equilibrium created by the muscles that surround the shoulder. This equilibrium is largely created by the deltoid and rotator cuff. The deltoid is the large triangular muscle that is palpable on the side of one’s arm. It provides an upward directed force on the shoulder and assists with elevation, extension and lateral movement of the arm. The rotator cuff, in comparison, is made up of four muscles (subscapularis, supraspinatus, infraspinatus, and teres minor) and they provide a downward and medially directed force which helps rotate and stabilize the shoulder. In a normal shoulder, therefore, the upward pull by the deltoid is balanced and countered by the downward force of the rotator cuff keeping the ball centered in the socket and thereby creating a smooth range of motion.
Unfortunately, in the setting of a large rotator cuff tear, the stability and resting balance of the shoulder is disrupted. This creates a situation where the upward pull by the deltoid is now unopposed allowing the ball to drift upwards and essentially “escape” from the socket. Normal motion becomes disrupted and patients may experience sensations of grinding and rubbing as the ball now articulates with the roof (acromion) of the shoulder socket. Over a period of time, a subset of people may also develop arthritis of the ball and socket (20-30%) and the combination of a large rotator cuff tear with arthritis is termed rotator cuff arthropathy.
Patients with rotator cuff arthropathy will typically complain of progressive pain, loss of motion, swelling, and mechanical symptoms such as catching or grinding with motion. Night pain is a frequent occurrence and range of motion is often progressively hindered. Feelings of weakness with overhead activities and gradual atrophy of the musculature around the shoulder is also routinely demonstrated. The shoulder may even dislocate (anterosuperior escape) with attempts at lifting the arm forward. Over time, activities of daily living become greatly impaired with inability to bathe, dress, groom or eat.
Non-operative treatment is usually the first line of management for patients diagnosed with this problem. This includes activity modification, anti-inflammatories, intermittent steroid injections, and physical therapy. The goal of physical therapy is to preserve range of motion. Strengthening exercises are generally avoided as this can create unnecessary pain. Patients with low demands typically respond favorably with nonsurgical modalities.
Patients with rotator cuff arthropathy typically have two surgical options: arthroscopic debridement versus arthroplasty. Arthroscopic surgery will not reverse the arthritis and is intended to be a palliative treatment. It may provide some improvement of pain but it is not predictable and can be short lived. Usually at the time of this surgery an attempt can be made to perform at least a partial repair of the rotator cuff depending on the extent of the arthritis with the intent of providing a little more strength and stability.
Reverse shoulder replacement surgery is the most predictable way to restore function and alleviate pain caused by rotator cuff arthropathy. While partial replacements (hemiarthroplasty) have and can be attempted, outcomes have been less than desirable with patients often reporting progressive pain and poor function following such intervention. The RSP (Reverse Shoulder Prosthesis–DJO Orthopedics) has revolutionized the treatment of this condition and has demonstrated a lower incidence of notching (major complication) as compared to the Grammont style implants. As part of his fellowship, Dr. Badman trained under the designer of this implant and completed training in one of the busiest reconstructive shoulder programs in the United States. Since completion of his training, Dr. Badman has consistently been one of the higher volume surgeons in the Midwest utilizing the RSP implant. He continues to remain extremely active in research of the device and routinely participates in lectures and teaching labs educating other surgeons throughout the United States on the technique of the surgical procedure.