3 months

Surgery

51.3

Injection

77.1

RR (95% CI)

0.665 (0.521 - 0.848)

P

0.001

6 months

Surgery

70.0

Injection

71.1

RR (95% CI)

0.985 (0.807 - 1.201)

P

1

12 months

Surgery

67.5

Injection

61.4

RR (95% CI)

1.009 (0.874 - 1.380)

P

0.513