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. 2016 Mar 6;2016:7627216. doi: 10.1155/2016/7627216

Table 2.

Outcomes compared between cemented versus AMA groups before and after PS matching.

Outcomes before and after PS matching
Before PS matching After PS matching Relative risk (95% CI) NNT (95% CI)
Cemented AMA p value Cemented AMA p value
146 cases 304 cases 128 cases 128 cases
Mean n or (range, SD) Mean n or (range, SD) Mean n or (range, SD) Mean n or (range, SD)
Duration of Surgery 69.1 mins (21–171, 23.6) 53.7 mins (20–135, 21.4) 0.000 67.7 mins (21–139, 22.5) 56.1 mins (21–135, 21.6) 0.000
General anaesthesia 26.7% 36 17.4% 53 0.022 25.8% 33 18.0% 23 0.131
Received blood transfusion 35.6% 52 38.2% 116 0.602 35.9% 46 32.0% 41 0.510
Died at 1 month 2.1% 3 3% 9 0.577 2.3% 3 0.0% 0 0.082
Died at 3 months 4.8% 7 7.9% 24 0.225 4.7% 6 3.1% 4 0.521
Died at 6 months 8.2% 12 11.8% 36 0.244 8.6% 11 8.6% 11 1.000
Died at 12 months 12.3% 18 19.1% 58 0.074 12.5% 16 15.6% 20 0.474
Total length of stay (mean, SD) 29.3 days (2–292, 26.9) 29.6 days (5–130, 16.8) 0.880 29.8 days (2–292, 28.4) 31.8 days (12–130, 18.0) 0.508

Fulfill clinical analysis criteria 88.4% 129 86.5% 263 0.585 88.3% 113 91.4% 117 0.410

post-op functional walker 83.7% 108 74.9% 197 0.053 81.4% 92 80.3% 94 0.868
post-op recreational walker 21.7% 28 5.3% 14 0.000 15.9% 18 9.4% 11 0.165
Unable to maintain walking function 42.6% 55 44.9% 118 0.746 45.1% 51 49.6% 58 0.512
post-op thigh pain 6.2% 8 22.4% 59 0.000 7.1% 8 24.8% 29 0.000 3.50 (1.67–7.33) 5.6 (3.7–11.8)

Fulfill complication analysis criteria 80.1 117 81.3 247 0.779 79.7% 102 82.0% 105 0.635

Cracks from attempted AMA 4.3% 5 4.9% 5
Complications 4.3% 5 21.9% 54 0.000 4.9% 5 21.9% 23 0.000 4.47 (1.77–11.30) 5.9 (3.8–12.5)
Loosening 2.6% 3 23.1% 57 0.000 2.9% 3 24.8% 26 0.000 8.42 (2.63–26.95) 4.6 (3.2–7.8)
Loosening before 1 year 2.6% 3 21.9% 54 0.000 2.9% 3 22.9% 24 0.000 7.77 (2.41–25.01) 5.0 (3.5–9.0)
Revision surgeries 3.4% 4 6.9% 17 0.233 3.9% 4 7.6% 8 0.374
Intraoperative crack 0.9% 1 5.3% 13 0.043 1.0% 1 6.7% 7 0.065
Dislocations 0.9% 1 3.2% 8 0.282 1.0% 1 3.8% 4 0.369
Infections 0.9% 1 2.8% 7 0.445 1.0% 1 2.9% 3 0.621
Traumatic periprosthetic fractures 0.9% 1 1.2% 3 1.000 1.0% 1 0.0% 0 0.493

NNT: number needed to treat.

Double sided Fisher's exact test for dichotomous variables.

Two-tailed Independent sampled t-test for continuous variables.