Joint Resurfacing: The Global® C.A.P.® Resurfacing Humeral Head Implant
Joint resurfacing is an alternative to total joint replacement surgery. It is a surgical procedure that allows patients to retain much of their natural tissue by replacing only the diseased part of the joint instead of the entire joint. This gradual approach to surgery means the patient may still be able to have a total joint replacement later if necessary.
The Global® C.A.P.® Resurfacing Humeral Head Implant is for patients with arthritis, rheumatoid arthritis or humeral head fractures. It is an option for younger, more active patients who might otherwise postpone surgery.
About Global C.A.P. resurfacing
The shoulder is a ball-and-socket joint (see diagram below).
- The bone that connects the elbow and the shoulder is the humerus.
- The shoulder blade, or scapula, is the socket.
Arthritis and other problems can render the shoulder unusable. The Global C.A.P. resurfacing procedure treats patients with mild to moderate head wear, loss of cartilage, stiffness, loss of function and pain that does not respond to other treatments.
An alternative to total joint replacement
Joint resurfacing allows surgeons to recondition, or “resurface,” the humeral head without replacing the entire shoulder.
- In total shoulder replacement surgery, the ball of the humerus and the socket of the scapula are replaced with three separate components.
- In joint resurfacing, the single Global C.A.P. implant is fitted onto the top of the humeral bone, preserving more of the patient’s tissue.
Resurfacing provides pain relief at an earlier stage of joint disease, while still making it possible to have a full shoulder replacement later if one becomes necessary. The Global C.A.P. implant is a more conservative option for younger patients because it spares the patient's healthy tissue, replacing only the diseased tissue.
What are the Global C.A.P. components?
The Global C.A.P. implant is a single component made of cobalt chrome. The implant is specially designed to allow surgeons to retain as much of the patient’s healthy tissue and bone as possible. It attaches to the humeral head (the top of humerus or the “ball” of the ball-and-socket joint). The implant is secured by a short, metal stem that has an undersurface of porous coating. Orthopaedic implants are secured one of two ways, either with bone cement or by natural tissue growth. The Global C.A.P. implant is cementless and uses the patient’s natural tissue growth for fixation. The sandpaper-like porous coating allows the patient’s tissue to naturally grow onto the implant. Doctors call this biological tissue in-growth, or biological fixation.
The Global C.A.P. has a specialized dome shape designed for optimum implant fixation and stability as well as comfort. The Global C.A.P. implant comes in an array of sizes so surgeons can choose the best fit for each patient.
Who is a candidate for surgery with Global C.A.P. resurfacing?
The Global C.A.P. is intended to repair arthritic damage and humeral head fractures, but not rotator cuff tears. The Global C.A.P. implant is not intended to be used in patients with local infections or poor bone quality. The Global C.A.P. can be used for younger patients or patients who are at an early stage in their joint disease. Only an orthopaedic surgeon trained in shoulder injuries and shoulder joint replacement can determine whether the Global C.A.P. is right for you.
Warnings and precautions
The use of a glenoid prothesis in patients with cuff tear arthropathy could increase the risk of glenoid component loosening due to non-anatomic loading conditions. The following conditions tend to adversely affect shoulder replacement implants: excessive patient weight, high levels of patient activity, likelihood of falls, poor bone stock, metabolic disorders, and disabilities of other joints.
Adverse events
The following are the most frequent adverse events after shoulder arthroplasty: change in position of the components, loosening of components, dislocation, infection, hematoma, pneumonia, and cardiovascular disorders.
Last Updated: 09/26/2008
