Saturday, November 16, 2013

Total shoulder arthroplasty

Total shoulder arthroplasty
A general description can be seen here.
A video including the surgical technique and patient interview can be found here.

1. Description - a glenohumeral joint replacement for shoulder arthritis in which the arthritic humeral head is replaced with an metal ball fixed to a stem inserted in the humeral shaft

and the glenoid of the scapula (shoulder blade)  is resurfaced with a high density polyethylene component. 

2. Indications - A total shoulder arthroplasty is offered to individuals with arthritis of the shoulder, a functioning rotator cuff and good bone stock. This procedure is used for primary and secondary osteoarthritis, posttraumatic arthritis, capsulorrhaphy arthropathy, and inflammatory arthritis.

3. Technique -

Information about the use of eccentric humeral head components to optimize glenohumeral stability can be found here.

A discussion of factors informing the selection of the humeral component is included in this link and in this link

Here is our method for the initial preparation of the humerus - see this link.

Here is our method for inserting the humeral component - see this link.

Here is our method for inserting the glenoid component - see this link.

4. Rehabilitation - The most important aspect of the post operative rehab program is preventing stiffness - using the exercises shown here. For this reason we usually use continuous passive motion immediately after surgery.  Here is some information on activities recommended after surgeryMaintaining range of motionRange of motion videosMore rehabilitation.

Once the range of motion is well established and after 6 weeks, we usually start early strengthening and

5. Results - The results of total shoulder arthroplasty depend on the diagnosis for which the procedure is performed: best results are obtained for primary osteoarthritis, while less optimal results may be see with post traumatic arthritis or chondrolysis. The results also depend on the physical and mental health of the patient: active patients without major medical or emotional issues fare better. The results also depend on the type of procedure: the best reported results have been obtained with all-polyethlene components, for example. Finally, the results depend on the experience of the surgeon: surgeons performing many of these procedures each year have better results and fewer than those who perform them rarely. Overall, the results of total shoulder arthroplasty can be summarized as posted here. Additional posts are listed below.

6. Complications - the possible risks of the total shoulder procedure include stiffness, pain, infection, fracture and glenoid component failure. If stiffness and pain are persistent at six weeks after surgery, a gentle manipulation under anesthesia with complete muscle relaxation is often helpful. If stiffness is present months after the procedure, a surgical soft tissue releaseis an option. Infection is uncommon after this procedure, especially if advanced prophylactic antibiotics (Ceftriaxone and Vancomycin) are used before and for a day after surgery. Fractures are extremely rare with the impaction bone grafting technique. Glenoid component failure is a concern and make take the form of either wear or loosening. The glenoid component is at risk because, in contrast to the situation in hip arthroplasty, the glenoid component is often loaded away from its center = eccentric loading. This eccentric loading can cause local wear and cold flow of the polyethylene. It can also give risk to rocking horse loosening of the glenoid component. This complication can be minimized by careful attention to surgical technique, including the use of a pegged all-polyethlene glenoid component, careful reaming of the glenoid bone so that a close fit is obtained with the back of the component, minimizing the use of cement, assurance that the humeral component is centered in the glenoid, accurate soft tissue balancing, and careful rehabilitation that protects the subscapularis and the rotator cuff.

More information on the total shoulder can be found here
Check out the new Shoulder Arthritis Book - click here.