Reverse Shoulder

• about
• education
• f.a.q.
• find a surgeon
• precautions

Reverse Shoulder Prosthesis

CAUTION: Federal Law (USA) restricts this device to sale by or on the order of a physician.

Indications

The Reverse Shoulder Prosthesis is indicated for use in patients with:
- Grossly rotator cuff deficient shoulder joint with severe arthropathy;
- Failed joint replacement with a grossly rotator cuff deficient shoulder joint;
- Evidence of upward displacement of the humeral head with respect to the glenoid;
- Loss of glenohumeral joint space;
- Patients must have a functional deltoid muscle.

Contraindications

Total joint replacement is contraindicated where there is:
- Non-functional deltoid muscle;
- Active sepsis;
- Excessive glenoid bone loss;
- Pregnancy;
- Muscular, neurological or vascular deficiencies, which compromise the affected extremity;
- Conditions that place excessive demand on the implant (i.e., Charcot’s joints, muscle deficiencies, refusal to modify postoperative physical activities, skeletal immaturity);
- Known metal allergy (I.e., jewelry).

Precautions and Warnings

This shoulder is a semi-constrained device designed to address irreparable soft tissue, irreparable rotator cuffs, musculature and bony deficiencies. Due to the constraints built into the design, there may be limits to the patient’s achievable range of motion. In addition, because of the limit to the range of motion, there may be the possibility of impingement and/ or additional wear.

The ranges of motion below are based on invitro testing. Clinical results may vary based on an individual patient’s skeletal and soft tissue makeup. Total arcs of motion achieved may be greater or less than the degrees measured invitro since these motions are influenced by other body kinematics.

Range of Motion

Adverse Effects

1. Accelerated wear of the polyethylene articulating surfaces have been reported following total shoulder replacement. Such wear may be initiated by particles of cement, metal, or other debris which can cause abrasion of the articulating surfaces. Accelerated wear shortens the useful life of the prosthesis, and leads to early revision surgery to replace the worn prosthetic components.
2. Metallosis and osteolysis may be implicated from wear debris associated with the use of orthopedic implants.
3. Peripheral neuropathies have been reported following total joint surgery. Subclinical nerve damage occurs more frequently, possibly the result of surgical trauma.
4. Metal sensitivity reactions in patients following joint replacement have been rarely reported. Implantation of foreign material in tissues can result in histological reactions involving macrophages and fibroblasts. The clinical significance of this effect is uncertain, as similar changes may occur as a precursor to, or during the healing process. In some cases, wear debris can initiate the process of histiocytic granuloma formation and consequent osteolysis and loosening of the implant.
5. Dislocation and subluxation of implant components can result from improper positioning of the components. Muscle and fibrous tissue laxity can also contribute to these conditions.
6. Implants can loosen or migrate due to trauma or loss of fixation.
7. Infection can lead to failure of the joint replacement.
8. While rare, fatigue fracture of the implant can occur as a result of strenuous activity, improper alignment, or duration of service.
9. Fracture of the humerus can occur while press-fitting (seating) the humeral stem into the prepared humeral canal.
10. Allergic reactions.

Intraoperative and early postoperative complications can include:

1) humeral perforation, or fracture;
2) humeral fracture can occur while seating the device;
3) damage to blood vessels;
4) temporary or permanent nerve damage resulting in pain or numbness of the affected limb;
5) undesirable shortening or lengthening of the limb;
6) traumatic arthrosis of the shoulder from intraoperative positioning of the extremity;
7) cardiovascular disorders including venous thrombosis, pulmonary embolism, or myocardial infarction; 8) hematoma;
9) delayed wound healing; and
10) infection.

Late postoperative complications can include:

1) avulsion as a result of excess muscular weakening;
2) non-union due to inadequate reattachment and/or early weight bearing;
3) aggravated problems of other joints of the affected limb or muscle deficiencies;
4) humeral fracture by trauma or excessive loading, particularly in the presence of poor bone stock;
5) periarticular calcification or ossification, with or without impediment to joint mobility;
6) inadequate range of motion due to improper selection or positioning of components, by impingement, and calcification.