Total Shoulder Replacement
In a total shoulder, the ball's arthritic surface is replaced with a metal ball with a stem that is press-fit in the inside of the arm bone (humerus) and the socket is resurfaced with a high-density polyethene component.
After a general or regional anaesthetic, this procedure is performed through an incision between the deltoid and the pectoralis major muscles on the front of the shoulder. It includes the release of adhesions and contractures and removing bone spurs that may block a range of motion.
How Is The Humeral Component Fixed In The Humerus?
While some surgeons cement the humeral component and others use implants that foster bone ingrowth, we find that these approaches stiffen the bone making it more likely to fracture in a fall on the one hand and greatly complicating any revision surgery that may become necessary in the future on the other. We prefer to fix the component by impaction grafting the inside of the humerus (using bone harvested from the humeral head that has been removed) until a tight press fit of the implant is achieved.
How Is The Glenoid Component Fixed To The Glenoid Bone?
The bone of the glenoid is precisely shaped with a glenoid reamer and then the glenoid component is secured with a combination of press-fitting and cementing.
In order for proper healing to occur, the patient must maintain the range of motion achieved at the surgery with simple, frequent stretching exercises.
Rehabilitative exercises are started immediately after surgery using continuous passive motion and stretching by the patient.
Attaining and maintaining at least 150 degrees of forwarding elevation is critical to the success of this procedure. The forward lean and the supine stretch can be helpful in getting there and maintaining this range of motion.
Who Should Consider A Total Shoulder?
Surgery for shoulder arthritis should only be considered when arthritis limits the patient’s life quality and after a trial of physical therapy and mild analgesics. Severe arthritis is usually best managed by either a partial or a complete joint replacement. Total shoulder arthroplasty (replacing the surfaces of both the ball and the socket) is usually considered by individuals who want the best chance of a rapid recovery of shoulder comfort and performing activities of daily living.
Who Should Probably Not Consider A Total Shoulder Replacement?
This procedure is less likely to be successful in individuals with depression, obesity, diabetes, Parkinson’s disease, multiple previous shoulder surgeries, shoulder joint infections, rotator cuff deficiency and severely altered shoulder anatomy.
What Happens After Surgery?
Total shoulder arthroplasty is a major surgical procedure that involves cutting of skin, tendons and bone. The pain from this surgery is managed by the anaesthetic and by pain medications. Immediately after surgery, strong medications (such as morphine or Demerol) are often given by injection. Within a day or so, oral pain medications are usually sufficient. The shoulder rehabilitation program is started on the day of surgery. The patient is encouraged to be up and out of bed soon after surgery and progressively reduce their use of pain medications. Hospital discharge usually takes place on the second or third day after surgery. Patients are to avoid lifting more than one pound, pushing and pulling for six weeks after surgery. Driving is recommended only after the shoulder has regained comfort and the necessary motion and strength. This may take several weeks after surgery. Thus the patient needs to be prepared to have less arm function for the first month or so after surgery than immediately before surgery. For this reason, patients usually require some assistance with self-care, activities of daily living, shopping and driving for approximately six weeks after surgery. Management of these limitations requires planning to accomplish daily living activities during the recovery period.
What About Rehabilitation?
Early motion after a total shoulder replacement is critical for achieving optimal shoulder function.
Arthritic shoulders are stiff. Although a major goal of the surgery is to relieve this stiffness by releasing scar tissue, it may recur during the recovery process if the range of motion exercises are not accomplished immediately. For the first 6 weeks of the recovery phase, the focus of rehabilitation is on maintaining the motion recovered at the surgery. Strengthening exercises are avoided during the first 6 weeks to stress the tendon repair before it heals back to the bone. Later on, once the shoulder is comfortable and flexible, strengthening exercises and additional activities are started. Some patients prefer to carry out the rehabilitation program themselves. Others prefer to work with a physical therapist who understands the total shoulder program.
When Can Ordinary Daily Activities Be Resumed?
In general, patients can perform gentle daily living activities using the operated arm from two to six weeks after surgery. Walking is strongly encouraged. Driving should wait until the patient can perform the necessary functions comfortably and confidently. Recovery of driving ability may take six weeks if the surgery has been performed, because of the increased demands on the left shoulder for shifting gears. With their surgeon's consent, patients can often return to activities such as swimming and golf at six months after their surgery.
Once A Shoulder With A Total Shoulder Procedure Has Successfully Completed The Rehabilitation Program, What Activities Are Permissible?
Once the shoulder has a nearly full range of motion, strength and comfort, we recommend that the shoulder be protected from heavy lifting loads and impact. Thus we discourage chopping wood, training with heavy weights, vigorous hammering, and recreational activities that subject the shoulder to impact loading.
What Problems Can Complicate A Total Shoulder And How Can They Be Avoided?
Like all surgeries, the total shoulder operation can be complicated by infection, nerve or blood vessel injury, fracture, instability, component loosening, and anaesthetic complications. Furthermore, this is a technically exacting procedure and requires an experienced surgeon to optimize the bony, prosthetic and soft tissue anatomy after the procedure. The procedure can fail if the reconstruction is too tight, too loose, improperly aligned, insecurely fixed, or unwanted bone-to-bone contact occurs. The most common cause of failure in the short term is a patient’s inability to maintain the range of motion achieved at the surgery during the healing period, which can last up to six months after surgery. The most common long-term problem is wearing or loosening of the glenoid component.
Reverse shoulder arthroplasty
A conventional shoulder replacement device mimics the normal anatomy of the shoulder: a plastic "cup" is fitted into the shoulder socket (glenoid), and a metal "ball" is attached to the top of the upper arm bone (humerus). In a reverse total shoulder replacement, the socket and metal ball are switched. The metal ball is fixed to the socket, and the plastic cup is fixed to the upper end of the humerus.
A reverse total shoulder replacement works better for people with cuff tear arthropathy because it relies on different muscles to move the arm. In a healthy shoulder, the rotator cuff muscles help position and power the arm during the motion range. A conventional replacement device also uses the rotator cuff muscles to function properly. These muscles no longer function in a patient with a large rotator cuff tear and cuff tear arthropathy. The reverse total shoulder replacement relies on the deltoid muscle, instead of the rotator cuff, to power and position the arm.
Reverse total shoulder replacement may be recommended if you have
A completely torn rotator cuff that cannot be repaired
Cuff tear arthropathy
A previous shoulder replacement that was unsuccessful
A complex fracture of the shoulder joint
A chronic shoulder dislocation
A tumour of the shoulder joint