Background
Methods
Retrieval strategies
Inclusion criteria
Data extraction
Quality assessment
Statistical analysis
Results
Study selection
Study characteristics
Study
|
Publication year
|
Country
|
Study design
|
Group size (fractures)
|
Total patients (fractures)
|
Major complications (fractures)
|
Average age (years)
|
Operative approach
|
Closure method
|
Follow-up period (months)
| |
---|---|---|---|---|---|---|---|---|---|---|---|
Case
|
Control
| ||||||||||
Wu [14] | 2014 | China | Case–control study | 21 | 218 | 209 (239) | 0 | 37.6 | L-shaped lateral | 2 layer | NA |
Soni [15] | 2014 | UK | Retrospective cohort study | 10 | 59 | 69 (69) | 2 | 38.0 | L-shaped lateral | 2 layer | NA |
Backes [22] | 2014 | Netherlands | Case-control study | 57 | 134 | 191 (191) | 19 | NA | Extended lateral | 1 layer/2 layer | >12.0 |
Ding [16] | 2013 | China | Case-control study | 87 | 413 | 479 (490) | 59 | 45.0 | L-shaped lateral | 2 layer | 14.2 |
Hao [17] | 2013 | China | Case-control study | 17 | 46 | 58 (63) | 3 | 35.0 | L-shaped lateral | 2 layer | 12.0 |
Court-Brown [21] | 2009 | UK | Case-control study | 45 | 133 | 178 (178) | 10 | 41.0 | Extended lateral | NA | NA |
Koski [18] | 2005 | Finland | Case-control study | 35 | 113 | 126 (148) | 20 | 39.8 | L-shaped lateral | 2 layer | 10.7 |
Assous [23] | 2001 | UK | Retrospective cohort study | 13 | 27 | 40 (40) | 0 | 35.0 | NA | NA | 27.0 |
Al-Mudhaffar [19] | 2000 | UK | Case-control study | 6 | 27 | 30 (33) | 2 | 41.0 | NA | 2 layer | 48.0 |
Folk [20] | 1999 | USA | Case-control study | 58 | 132 | 179 (190) | 40 | 35.0 | L-shaped lateral | 2 layer | NA |
Total | -- | -- | -- | 349 | 1302 | 1559 (1651) | 155 | 40.4 | -- | -- | -- |
Study quality
Case–control study
|
Selection
|
Comparability
|
Exposure
|
Total quality score
| |||||
---|---|---|---|---|---|---|---|---|---|
Adequate definition of cases
|
Representativeness of cases
|
Selection of controls
|
Definition of controls
|
Control for important factors or additional factors
|
Ascertainment of exposure (blinding)
|
Same method of ascertainment for subjects
|
Non-response rate
| ||
Wu [14] | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 8 |
Backes [22] | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 7 |
Ding [16] | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 8 |
Hao [17] | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 6 |
Court-Brown [21] | 0 | 1 | 0 | 1 | 1 | 1 | 0 | 1 | 5 |
Koski [18] | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 7 |
Al-Mudhaffar [19] | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 8 |
Folk [20] | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 8 |
Cohort study
|
Selection
|
Comparability
|
Outcome
|
Total quality score
| |||||
Representativeness of the exposed cohort
|
Selection of the non-exposed cohort
|
Ascertainment of exposure
|
Demonstration that outcome of interest was not present at start of study
|
Control for important factors or additional factors
|
Assessment of outcome
|
Follow-up was long enough for outcomes to occur
|
Adequacy of follow up of cohorts
| ||
Soni [15] | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 7 |
Assous [23] | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 7 |
Meta-analysis results
Potential risk factors
|
No. of studies
|
Exposed group
|
Non-exposed group
|
Pooled OR
|
95% CI
|
P value
|
I
2
|
---|---|---|---|---|---|---|---|
Female | 4 | 66/299 | 142/618 | 0.83 | 0.42-1.87 | 0.59 | 65% |
Surgery timing (d) >14 (vs.≦14) | 3 | 32/135 | 48/188 | 0.86 | 0.51-1.46 | 0.58 | 0% |
Bone graft | 4 | 54/252 | 117/730 | 1.74 | 1.17-2.59 | 0.007 | 49% |
Smoking | 10 | 180/681 | 169/963 | 1.90 | 0.97-3.30 | 0.06 | 80% |
Hypertension | 2 | 22/114 | 82/384 | 0.92 | 0.54-1.56 | 0.75 | 0% |
Sanders classification (II.III/IV) | 4 | 37/98 | 134/707 | 3.31 | 2.02-5.44 | <0.00001 | 0% |
Diabetes | 4 | 20/33 | 94/367 | 9.97 | 4.43-23.50 | <0.00001 | 0% |
Drinking | 2 | 26/107 | 48/142 | 0.85 | 0.19-3.76 | 0.83 | 55% |
No drainage | 2 | 63/268 | 15/162 | 5.68 | 2.91-11.09 | <0.00001 | 0% |
Female | 4 | 66/299 | 142/618 | 0.83 | 0.42-1.87 | 0.59 | 65% |
Potential risk factors
|
No. of studies
|
Exposed group
|
Non-exposed group
|
Pooled OR
|
95% CI
|
P value
|
I
2
|
---|---|---|---|---|---|---|---|
Surgery timing (d) >14 (vs.≦14) | 2 | 15/125 | 13/135 | 1.26 | 0.58-2.74 | 0.57 | 15% |
Smoking | 2 | 12/117 | 15/134 | 0.99 | 0.46-2.17 | 0.99 | 36% |
Variables
|
Study variance (ţ
2
)
|
P value
|
Residual variation due to heterogeneity (I
2
)
|
---|---|---|---|
Publication year | 1.04 | 0.75 | 80.85% |
Study design | 0.86 | 0.26 | 79.73% |
Operative approach | 1.06 | 0.89 | 80.70% |
Type of closure | 0.94 | 0.35 | 78.99% |
Study quality | 0.78 | 0.18 | 74.83% |
Study region | 0.88 | 0.26 | 78.71% |