BACKGROUND:
Reported early complication rates in reverse total shoulder arthroplasty have widely varied from 0% to 75% in part due to a lack of standard inclusion criteria. In addition, it is unclear whether revision arthroplasty is associated with a higher rate of complications than primary arthroplasty.

QUESTIONS/PURPOSE:
We therefore (1) determined the types and rates of early complications in reverse total shoulder arthroplasty using defined criteria, (2) characterized an early complication-based learning curve for reverse total shoulder arthroplasty, and (3) determined whether revision arthroplasties result in a higher incidence of complications.

PATIENTS AND METHODS:
From October 2004 to May 2008, an initial series of 200 reverse total shoulder arthroplasties was performed in 191 patients by a single surgeon. Forty of the 200 arthroplasties were revision arthroplasties. Of these, 192 shoulders were available for minimum 6-month followup (mean, 19.4 months; range, 6-49.2 months). We determined local and systemic complications and distinguished major from minor complications.

RESULTS:
Nineteen shoulders involved local complications (9.9%), including seven major and 12 minor complications. Nine involved perioperative systemic complications (4.7%), including eight major complications and one minor complication. The local complication rate was higher in the first 40 shoulders (23.1%) versus the last 160 shoulders (6.5%). Seven of 40 (17.5%) revision arthroplasties involved local complications, including two major and five minor complications compared to 12 of 152 (7.9%) primary arthroplasties, including five major and seven minor complications. Nerve palsies occurred less frequently in primary arthroplasties (0.6%) compared to revisions (9.8%).

CONCLUSIONS:
The early complication-based learning curve for reverse total shoulder arthroplasty is approximately 40 cases. There was a trend toward more complications in revision versus primary reverse total shoulder arthroplasty and more neuropathies in revisions.

LEVEL OF EVIDENCE:
Level IV, therapeutic study. See the guidelines online for a complete description of level of evidence.





Polls results
1

On a scale of 1 to 10, rate how much this article will change your clinical practice?

NO change
BIG change
100% Article relates to my practice (1/1)
0% Article does not relate to my practice (0/1)
0% Undecided (0/1)
2

Will this article lead to more cost-effective healthcare?

0% Yes (0/1)
100% No (1/1)
0% Undecided (0/1)
3

Was this article biased? (commercial or personal)

0% Yes (0/1)
100% No (1/1)
0% Undecided (0/1)
4

What level of evidence do you think this article is?

0% Level 1 (0/1)
0% Level 2 (0/1)
100% Level 3 (1/1)
0% Level 4 (0/1)
0% Level 5 (0/1)