Appendix 3. Summary of findings from 45 studies describing postoperative complications by sex
Study
Intervention
Complication
Total
number
Males,
number (%)
Bazaz et al.
(2002) [2]
Anterior
cervical spine
surgery
Dysphagia
221
115 (52.0*)
Cahill et al.
(2009) [3]
Anterior
All
cervical spinal complications
fusion
27,067
Cahill et al.
(2009) [3]
Posterior
All
cervical spinal complications
fusion
Cahill et al.
(2009) [3]
Thoracic
spinal fusion
Cahill et al.
(2009) [3]
Lumbar spinal All
fusion
complications
All
complications
T1
Females,
number
(%)
106
(48.0*)
Total
Males–
complications complications,
number (%)
*
37
13 (35.1*)
13,022*
(48.1*)
14,055*
(51.9*)
1321*
711 (54.0)
2869
1619*
(56.4*)
1249*
(43.5*)
286*
165 (58.0)
3257
1600*
(49.1*)
1657*
(50.9*)
561*
315 (56.0)
36,807
15,931*
(43.3*)
20,888*
(56.8*)
2613*
1155 (44.0)
Females–
Findings
complications,
number (%)
24 (64.9*)
Males at
decreased risk
for incidence of
dysphagia at 6
months
postoperatively
(p = 0.023)
610 (46.0)
Females at
decreased odds
for all
complications;
OR, 0.78 (95%
CI, 0.7–0.87)
121 (42.0)
No significant
difference in
overall
complication rate
between sexes;
OR, 0.94 (95%
CI, 0.73–1.2)
246 (44.0)
Females at
decreased odds
for all
complications;
OR, 0.71 (95%
CI, 0.59–0.85)
1458 (56.0)
No significant
difference in
overall
complication rate
T2
Chen et al.
(2009) [4]
Spine surgery
Surgical site
infection
195*
NR
NR
27*
NR
NR
Cloyd et al.
(2010) [5]
Multilevel
spinal fusion
surgery
Major
complications
124
56 (45.2)
68*(54.8*)
25
NR
NR
Cloyd et al.
(2010) [5]
Multilevel
spinal fusion
surgery
Reoperation
124
56 (45.2)
68*(54.8*)
26*
NR
NR
Cloyd et al.
(2010) [5]
Multilevel
spinal fusion
surgery
All
complications
124
56 (45.2)
68*(54.8*)
NR
NR
NR
Danto et al.
(2012) [6]
Cervical
discectomy
Dysphagia
149
80 (53.0)
69 (46.0)
18
NR
NR
between sexes;
OR, 0.96 (95%
CI, 0.87–1.04)
No significant
difference in
surgical site
infection rate
between sexes;
OR, 1.305 (95%
CI, 0.605–2.816)
Males at
increased odds
of major
complications in
multivariate
analysis; OR,
4.56 (95% CI,
1.28–16.24)
No significant
difference in
reoperation rate
between sexes;
OR, 0.94 (95%
CI, 0.41–2.17)
No significant
difference in
overall
complication rate
between sexes;
OR, 1.44 (95%
CI, 0.71–2.94)
No significant
difference in rate
T3
Danto et al.
(2012) [6]
Cervical
discectomy
Dysphonia
149
80 (53.0)
69 (46.0)
8
NR
NR
Deyo et al.
(1992) [7]
Lumbar spine
surgery
All
complications
18,122
10610
(59.0)
7512
(41.0)
1649*
934*(56.6*)
721*(43.7*)
Deyo et al.
(2010) [8]
Lumbar spinal Cardiostenosis
pulmonary
surgery
complications
or stroke
32,152
14,909
(46.0*)
17,243
(54.0)
984
472 (48.0*)
512 (52.0*)
of dysphagia and
dysphonia
combined
between sexes;
OR, 1.3 (95%
CI, 0.5–3.2)
No significant
difference in rate
of dysphagia and
dysphonia
combined
between sexes;
OR, 1.3 (95%
CI, 0.5–3.2)
No significant
difference in
total
complication rate
between sexes,
but females at
decreased risk of
combined
complications
and prolonged
hospitalization;
RR, 0.87 (95%
CI, 0.77–0.97)
No significant
difference in
cardiopulmonary
complication or
stroke rate
between sexes (p
T4
*
*
Deyo et al.
(2010) [8]
Lumbar spinal Wound
stenosis
complications
surgery
32,152
14,909
(46.0*)
17243
(54.0)
398
179 (45.0 )
219 (55.0 )
Fang et al.
(2005) [9]
Spinal surgery Infection
120
50 (42.0*)
70 (58.0*)
43
21 (48.8*)
22 (51.2*)
Fineberg et al.
(2013) [16]
Cervical spine
surgery
20,2694
99,320*
(49.0*)
103,374*
(51.0)
1080
598*(55.4)
482*(44.6)
Fineberg et al.
(2013) [11]
Lumbar spinal Gastrointestina 220,522
fusion
l hemorrhage
NR
NR
310
NR
NR
Fineberg et al.
(2013) [14]
Lumbar spine
surgery
NR
NR
1042
NR
NR
Aspiration
Pulmonary
embolism
577415
> 0.05)
No significant
difference in
wound
complication rate
between sexes
(p > 0.05)
No significant
difference in
infection rate
between sexes (p
= 0.25); OR,
1.58 (95% CI,
0.73–3.4)
Males at
increased odds
of aspiration (p <
0.001); OR, 1.4
(95% CI, 1.2–
1.6)
Males at
increased odds
of GI
hemorrhage (p <
0.001); OR, 2.3
(95% CI, 1.7–
3.0)
Males at
increased odds
of pulmonary
embolism (p =
0.006); OR, 1.3
(95% CI, 1.1–
T5
Fineberg et al.
(2013) [15]
Cervical spine
surgery
Perioperative
cardiac
complication
214,900
105,360*
(49.0*)
109,540*
(51.0*)
857
479*(55.9*)
378*(44.1)
Fineberg et al.
(2013) [10]
Lumbar spine
surgery
Perioperative
cardiac
complication
578,457
285,156*
(49.0*)
293,301*
(51.0*)
3848
1874*(48.7*)
1974*(51.3)
Fineberg et al.
(2014) [12]
Anterior
lumbar fusion
Postoperative
ileus
19,762
8930*
(45.0*)
10,832*
(55.0*)
1481
813*(54.9*)
668*(45.1)
Fineberg et al.
Posterior
Postoperative
18,2801
79,687*
103,114*
4749
2769*(58.3*)
1980*(41.7)
1.5); study DVT
data did not meet
our inclusion
criteria
Females at
decreased risk
for perioperative
cardiac
complications (p
< 0.0005) in
univariate
analysis
Males at
increased odds
of perioperative
cardiac
complications (p
< 0.0005); OR,
1.2 (95% CI,
1.1–1.3)
Males at
increased odds
of postoperative
ileus with this
surgery (p <
0.001) and for all
lumbar fusion
surgeries
combined (p <
0.001); OR, 1.9
(95% CI, 1.8–
2.0)
Males at
T6
(44.0*)
(56.0*)
(2014) [12]
lumbar fusion
ileus
Fineberg et al.
(2014) [12]
Anterior/
posterior
lumbar fusion
Postoperative
ileus
17,959
8251* (46.0*) 9708*
(
54.0*)
1511
817*(54.1*)
694*(45.9)
Fineberg et al.
(2013) [13]
Lumbar spine
surgery
Delirium
57,8457
285,758*
(49.4*)
292,699*
(50.6)
4857
2161*(44.5*)
2696*(55.5)
Friedman et al.
(2007) [17]
Laminectomy
Surgical site
infection
123*
80*(65.0*)
43*(35.0*)
41
24 (59.0)
17*(41.0*)
increased odds
of postoperative
ileus with this
surgery (p <
0.001) and for all
lumbar fusion
surgeries
combined (p <
0.001); OR, 1.9
(95% CI, 1.8–
2.0)
Males at
increased odds
of postoperative
ileus with this
surgery (p <
0.001) and for all
lumbar fusion
surgeries
combined (p <
0.001); OR, 1.9
(95% CI, 1.8–
2.0)
No significant
difference
between sexes in
postoperative
delirium rate in
multivariate
analysis
No significant
difference in
surgical site
T7
Garg et al.
(2010) [18]
Anterior
lumbar fusion
Vascular
injury
212
92*(43.4*)
120 (56.6)
13
10 (76.9*)
3 (23.1*)
Goz et al.
(2014) [19]
Spinal fusion
Venous
thromboembo
lic events
710,154
331,926
(46.7*)
378,228
(53.3*)
3514*
1925*(54.8*)
1589*(45.2*)
Gruskay et al.
(2014) [21]
ACDF
Major
complications
2164
1057 (49.1)
1107 (50.9) 71
46*(64.8*)
25*(35.2*)
Hoffmann et al. Posterolateral
(2013) [22]
fusion with
rhBMP-2
implant
Nonunion
requiring
reoperation
1158
468 (40.4)
690 (59.6)
41
24 (58.5)
17 (41.5)
Hoffmann et al. Posterolateral
(2013) [22]
fusion with
rhBMP-2
Seroma
requiring
reoperation
1158
468 (40.4)
690 (59.6)
32
12 (37.5)
20 (62.5)
infection rate
between sexes (p
= 0.29);
OR, 0.66 (95%
CI, 0.30–1.43)
Females at
decreased risk
for vascular
injury (p =
0.013)
Females at
decreased odds
of VTE (p =
0.0465); OR,
0.78 (95% CI,
0.62–1)
Males at
increased odds
of major
complications in
multivariate
analysis (p =
0.040); OR,
1.756 (95% CI,
1.027–3.003)
Males at
increased odds
for nonunion;
OR, 2.08 (95%
CI, 1.13–3.83)
Statistical
difference in
seroma rate
T8
implant
Hoffmann et al. Posterolateral
(2013) [22]
fusion with
rhBMP-2
implant
Infection
requiring
reoperation
1158
468 (40.4)
690 (59.6)
26
6 (23.1)
20 (76.9)
Horwitz and
Curtin (1975)
[23]
Laminectomy
Wound
infections
(sepsis)
496
333*(67.0*)
163 (33.0)
16
15 (93.8*)
1 (6.3*)
Javalkar et al.
(2011) [24]
Lumbar spinal Reoperation
stenosis
surgery
335
167 (49.9)
168 (50.1)
44
27 (61.4)
17 (38.6)
King et al.
(2009) [26]
Degenerative
cervical spine
disease
surgery
Reoperation
12,338
6693 (54.0)
5645
(46.0)
688
405 (59)
283 (41)
Koutsoumbelis
et al. (2011)
[27]
Spine surgery
Surgical site
infection
252
109 (43.3*)
143 (56.7*) 84
29 (34.4)
55 (65.6)
between sexes
NR
No significant
difference in
infection rate
between sexes (p
= 0.2198).
Females at
decreased risk
for wound
infection
(significance
level not
reported)
No significant
difference in
reoperation rate
between sexes;
OR, 1.2 (95%
CI, 0.586–2.635)
Males at
increased odds
of reoperation (p
= 0.038); OR,
1.17
No significant
difference in
surgical site
infection rate
between sexes in
multivariate
analysis (p =
0.07); OR, 1.95
T9
Kurtz et al.
(2012) [28]
Lumbar
fusion
Infection
15,674
5524 (35.2)
10,150
(64.8)
1355*
NR
NR
Lee et al.
(2007) [29]
Anterior
cervical spine
surgery
Dysphagia
310
158 (51.0*)
152
(49.0*)
48*
17* (35.0*)
31* (65.0*)
Lee et al.
(2012) [30]
Spine surgery
Medical
complications
1591
914 (57.0)
677 (43.0)
676
NR
NR
Lykissas et al.
(2014) [31]
Lateral
lumbar
interbody
fusion
Postoperative
anterior
thigh/groin
pain
451
179 (40.0*)
272
(60.0*)
241*
45* (19.0*)
196* (81.0*)
(95% CI, 0.95–
4.01)
No significant
difference in
infection rate
between sexes (p
= 0.2198)
Females at
increased risk for
dysphagia 12
months
postoperatively
(p < 0.02);
prevalence ratio
= 1.91 (95% CI,
1.1–3.33)
Females at
decreased risk of
pulmonary
complications
only in
multivariate
analysis (p =
0.024); RR, 0.65
(95% CI, 0.43–
0.94)
Males at
decreased odds
of anterior
thigh/groin pain
immediately
postoperatively
(p = 0.007); OR,
T10
Lykissas et al.
(2014) [31]
Lateral
lumbar
interbody
fusion
Motor deficit
451
179 (40.0*)
272
(60.0*)
139*
38* (27.0*)
101* (73.0*)
Lykissas et al.
(2014) [31]
Lateral
lumbar
interbody
fusion
Sensory
deficit
451
179 (40.0*)
272
(60.0*)
200*
59* (30.0*)
141* (70.0*)
Marquez-Lara
et al. (2014)
[33]
Lumbar
fusion
Cerebral
vascular
accidents
264,891
115,487*
(43.6*)
149,404*
(56.4*)
340
143* (42.1*)
197* (57.9)
Nandyala et al.
(2014) [35]
Spinal fusion
Visual loss
541,485
252,339*
(46.6*)
289,146*
(53.4*)
105
56* (53.3*)
49* (46.7)
Nassr et al.
(2012) [36]
Multilevel
cervical
C5 palsy
630
338 (53.7*)
292
(46.3*)
42
29 (69.0*)
13 (31.0*)
0.525 (95% CI,
0.329–0.838)
No significant
difference in
motor deficit rate
between sexes
immediately
postoperatively
(p = 0.913); OR,
0.974 (95% CI,
0.604–1.569)
No significant
difference in
sensory deficit
rate between
sexes
immediately
postoperatively
(p = 0.854); OR,
1.043 (95% CI,
0.665–1.635)
No significant
difference in
CVA rate
between sexes (p
= 0.569)
No significant
difference in
visual loss rate
between sexes (p
= 0.23)
Females at
decreased risk of
T11
decompression
Ogelsby et al.
(2013) [37]
Cervical spine
surgery
Deep vein
thrombosis
273,396
NR
NR
NR
NR
NR
Ogelsby et al.
(2013) [37]
Cervical spine
surgery
Pulmonary
embolism
273,396
NR
NR
NR
NR
NR
Pugely et al.
(2014) [39]
Lumbar spine
surgery
30-day
readmission
15,668
7964*(50.8*) 7704*(49.2*) 695
323*(46.5*)
372*(53.5)
Pull ter Gunne
et al. (2009)
[40]
Spinal surgery Clinical
infection
3174
1273 (40.1)
1901
(59.9)
132
58 (43.9*)
74 (56.1*)
Riley et al.
(2005) [42]
ACDF
454
237* (52.2)
217*(47.8)
128
NR
NR
Dysphagia
C5 palsy (p =
0.05)
Males at
increased odds
of DVT (p <
0.0005); OR, 1.5
(95% CI, 1.3–
1.8)
Males at
increased odds
of PE (p <
0.0005); OR, 1.8
(95% CI, 1.4–
2.4)
Statistical
difference in 30day readmission
rate between
sexes in
multivariate
analysis NR
No significant
difference in
clinical infection
rate between
sexes (p = 0.359)
No significant
difference in
dysphagia rate
between sexes (p
= 0.915); OR,
1.02 (95% CI,
0.68–1.55)
T12
268†
38 (14.2*)
231
(86.2*)
46
8 (17.4*)
38 (82.6*)
144
73 (50.7*)
71 (49.3*)
9*
1 (11.1*)
8 (88.9*)
Schoenfeld et
al. (2011) [50]
Iliac crest
Infection/
harvest for
dehiscence
anterior
cervical
fusion
Spinal surgery Major
complications
3475
1871 (54.0)
1604
(46.0)
179
NR
NR
Schoenfeld et
al. (2011) [50]
Spinal surgery Minor
complications
3475
1871 (54.0)
1604
(46.0)
128
NR
NR
Schoenfeld et
al. (2011) [50]
Spinal surgery All
complications
3475
1871 (54.0)
1604
(46.0)
263
NR
NR
Scheer et al.
(2013) [43]
Adult spinal
deformity
surgery
Schnee et al.
(1997) [44]
Reoperation
Statistical
difference in
reoperation rate
between sexes
NR
Males at
decreased risk of
infection/dehisce
nce (p <
0.00001)
No significant
difference in
major
complication rate
between sexes (p
= 0.5); OR, 1.11
(95% CI, 0.82–
1.5)
Females at
increased odds
of minor
complications (p
= 0.025); OR,
1.54 (95% CI,
1.06–2.25)
No significant
difference in
total
complication rate
between sexes in
multivariate
analysis; in
univariate
T13
Schoenfeld et
al. (2013) [47]
Spinal surgery DVT/PE
27,684
14,221
(51.4)
13,463
(48.6)
283
NR
NR
Schoenfeld et
al. (2013) [46]
Spinal fusion
Major
complications
5887
2782 (47.0)
3092
(53.0)
457
NR
NR
Schoenfeld et
al. (2013) [46]
Spinal fusion
Minor
complications
5887
2782 (47.0)
3092
(53.0)
270
NR
NR
Schoenfeld et
al. (2013) [46]
Spinal fusion
All
complications
5887
2782 (47.0)
3092
(53.0)
608
NR
NR
Schwab et al.
(2012) [51]
Spinal
deformity
surgery
Major
perioperative
complications
953
NR
NR
80
18 (32.5*)
54 (67.5*)
analysis, OR,
1.32 (95% CI,
1.02–1.69)
Males at
increased odds
of PE only (p =
0.0119); OR,
1.65 (95% CI,
1.12–2.44)
Statistical
difference in
major
complication rate
between sexes
NR
Males at
decreased odds
of minor
complications (p
= 0.004); OR,
0.7 (95% CI,
0.5–0.9)
Statistical
difference in
total
complication rate
between sexes
NR
Statistical
difference in
major
perioperative
complication rate
T14
NR
177,392*
NR
NR
76,349*
(47.8*)
83,241*
(52.2*)
4027*
2069* (51.4*)
1958* (48.6*)
58,428
29,438*
(50.4*)
28,990
(49.6)
4595
NR
NR
284,640
123,276*
(43.3*)
161,364
(56.7)
20,786
NR
NR
112
53 (47.3)
59 (52.7)
70
26 (37.1)
44 (62.9)
Shen et al.
(2009) [52]
Elective
spinal fusion
surgery
All
complications
122,8475 NR
Singh et al.
(2013) [53]
Anterior
cervical
fusion
Dysphagia
159,590
Wang et al.
(2012) [57]
Elective
30-day
cervical spinal readmission
surgery
Wang et al.
(2012) [57]
Lumbar spine
surgery
Zheng et al.
(2002) [59]
Posterior
Blood
lumbar spine
transfusion
decompression,
30-day
readmission
between sexes
NR
Males at
decreased odds
of all
complications (p
< 0.001); OR,
0.76 (95% CI,
0.75–0.78)
Males at
increased odds
of dysphagia (p
< 0.001); OR,
1.16 (95% CI,
1.07–1.25)
Males at
increased odds
of 30-day
readmission (p <
0.001); OR,
1.30; (95% CI,
1.22–1.39)
No significant
difference in 30day readmission
rate between
sexes (p =
0.514); OR, 1.01
(95% CI, 0.98–
1.04)
No significant
difference in
blood transfusion
T15
fusion, and
segmental
instrumentation
required between
sexes (p = 0.48);
OR, 1.57 (95%
CI, 0.44–5.59)
from information provided in the article; †as reported in the article; ACDF = anterior cervical decompression and fusion; rhBMP-2 = recombinant human bone morphogenetic protein2; OR = odds ratio; CI = confidence interval; RR = risk ratio; NR = not reported; GI = gastrointestinal; DVT = deep vein thrombosis; VTE = venous thromboembolism; CVA = cerebrovascular
accident; PE = pulmonary embolism.
*Calculated