Reverse Total Shoulder Arthroplasty

Question 1

What change to the COR occurs in a reverse TSA?

Answer 1

Moved medially and inferiorly

Question 2

What are indications for reverse TSA?

Answer 2

1) Pseudoparalysis secondary to rotator cuff arthropathy
2) Non-union or malunion of greater tuberosity
3) Rheumatoid
4) Failed arthroplasty

Ideal patient:
low functional demand
physiological age >70
sufficient glenoid bone stock
working deltoid muscle
intact axillary nerve

Question 3

What are contraindications to reverse TSA?

Answer 3

1) deltoid deficiency (axillary nerve palsy)
2) bony acromion deficiency
3) glenoid osteoporosis
4) active infection

Question 4

What increases the risk of scapular notching in reverse TSA?

Answer 4

Superiorly placed glenoid component, or insufficient inferior tilt of glenoid component on the native glenoid

Question 5

How is glenoid loosening treated in a reverse TSA?

Answer 5

Treat using staged procedure to fill glenoid cavity with autogenous bone and await incorporation with a hemiarthroplasty prior to reimplantation of a new glenosphere

Question 6

What is the strongest risk factor for dislocation in reverse TSA?

Answer 6

Irreparable subscapularis tear;

Also:
proximal humeral bone loss
failed prior arthroplasty
proximal humeral nonunion
fixed glenohumeral dislocation preop
NOT related to condition of rotator cuff

Question 7

What are the 2 major innovations of the Grammont reverse TSA?

Answer 7

1) a large glenoid hemisphere with no neck
2) a small humeral cup almost horizontally oriented with a nonanatomic inclination of 155 degrees, covering less than half of the glenosphere