Thirty-day mortality of patients with hip fracture during COVID-19 pandemic and pre-pandemic periods: A systematic review and meta-analysis

Table 1 Search strategy of Medline database

Keyword	Search strategy	No. of hits
COVID, COVID-19, Pandemic, Hip fracture, Trochanter fracture, Femur neck fracture	(("COVID"[All Fields] AND ("humans"[MeSH Terms] AND "medline"[Filter] AND "english"[Language]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language])) OR (("severe acute respiratory syndrome coronavirus 2"[Supplementary Concept] OR "severe acute respiratory syndrome coronavirus 2"[All Fields] OR "ncov"[All Fields] OR "2019 ncov"[All Fields] OR "covid 19"[All Fields] OR "sars cov 2"[All Fields] OR (("coronavirus"[All Fields] OR "cov"[All Fields]) AND 2019/11/01:3000/12/31[Date - Publication])) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND "english"[Language]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language])) OR (("pandemic s"[All Fields] OR "pandemically"[All Fields] OR "pandemicity"[All Fields] OR "pandemics"[MeSH Terms] OR "pandemics"[All Fields] OR "pandemic"[All Fields]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language]))) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language]) AND (((("hip fractures"[MeSH Terms] OR ("hip"[All Fields] AND "fractures"[All Fields]) OR "hip fractures"[All Fields] OR ("hip"[All Fields] AND "fracture"[All Fields]) OR "hip fracture"[All Fields]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language])) OR (("femur"[MeSH Terms] OR "femur"[All Fields] OR "trochanter"[All Fields] OR "trochanters"[All Fields]) AND ("fractur"[All Fields] OR "fractural"[All Fields] OR "fracture s"[All Fields] OR "fractures, bone"[MeSH Terms] OR ("fractures"[All Fields] AND "bone"[All Fields]) OR "bone fractures"[All Fields] OR "fracture"[All Fields] OR "fractured"[All Fields] OR "fractures"[All Fields] OR "fracturing"[All Fields]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND "english"[Language]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language])) OR (("femoral neck fractures"[MeSH Terms] OR ("femoral"[All Fields] AND "neck"[All Fields] AND "fractures"[All Fields]) OR "femoral neck fractures"[All Fields] OR ("femur"[All Fields] AND "neck"[All Fields] AND "fracture"[All Fields]) OR "femur neck fracture"[All Fields]) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language]))) AND ("humans"[MeSH Terms] AND "medline"[Filter] AND 1000/01/01:2020/08/01[Date - Publication] AND "english"[Language]))	24

COVID-19: Coronavirus disease 2019.

Table 2 Demographic properties, fracture type and surgical techniques in hip fractured patients treated during coronavirus disease 2019 and pre-coronavirus disease 2019 times (2020)

Study/country		Macey et al[9]/United Kingdom	Malik-Tabassum et al[38]/United Kingdom	Segarra et al[27]/Spain	Thakrar et al[19]/United Kingdom	Egol et al[20]/United States	Williams et al[28]/United Kingdom	Slullitel et al[39]/Argentina	Karayiannis et al[29]/United Kingdom
Study design		Retrospective study with prospective data collection	Retrospective observational studies	Longitudinal prospective cohort study	Prospective cohort study	Prospective cohort study	Retrospective observational study	Retrospective case-control study	Retrospective case-control study, multicentre
Sample size/ duration	Pre-COVID	76 (20th March 2019-24th April 2019)	174 [90 (23rd March 2018-11th May 2018); 84 (23rd March 2019-11th May 2019)]	70 (1st February 2019-15th April 2019)	99 [51 (15th March 2018-15th April 2018); 48 (15th March 2019-15th April 2019)]	115 (1st February 2019-15th April 2019)	15 (January 2020)	86 (1st December 2019-19th March 2020)	266 (18th March 2019-27th April 2019)
	COVID	76 (20th March 2020-24th April 2020)	68 (23rd March 2020-11th May 2020)	68 (1st February 2020-15th April 2020)	43 (15th March 2020-15th April 2020)	138 (1st February 2020-15th April 2020)	15 (March 2020)	74 (20th March 2020-31st May 2020)	203 (18th March 2020-27th April 2020)
	COVID +	10 (13.16%)	1 (1%)	2 (2.94%)	12 (27.9%)	31 (22.5%)	0	0	21 (10.35%)
	COVID −	66 (86.84%)	67 (99%)	66 (97%)	31 (72.1%)	107 (77.5%)	15 (100%)	74 (100%)	182 (89.65%)
NOS		8 (moderate risk)	8 (moderate risk)	7 (moderate risk)	8 (moderate risk)	9 (low risk)	7 (moderate risk)	8 (moderate risk)	7 (moderate risk)
Age (yr)	Pre-COVID	Median: 83 (IQR, 74-88)	2018: 82.9 ± 9.9; 2019: 83.8 ± 7.7	84 ± 7.8	2018: 81.6 ± 12.3; 2019: 84.0 ± 8.7	81.5 ± 10.7	86.6	Median: 86 (IQR, 78-90)	78.0 ± 12.8
	COVID	Median: 83 (73-87)	84.3 ± 8.9	82.4 ± 7.4	81.6 ± 11.3	83.0 ± 10.2	81.5	Median: 86 (IQR, 80–91)	81.3 ± 9.7
Sex, M:F	Pre-COVID	58:18	37:137	18:52	25:74	34:81	2:13	19:67	79:187
	COVID	58:18	25:43	21:47	23:20	50:88	3:12	9:65	65:138
BMI (kg/m2)	Pre-COVID	NM	NM	NM	NM	24.6 ± 5.2	NM	Median 24 (IQR, 21.7–26.6)	NM
	COVID	NM	NM	NM	NM	24.4 ± 5.1	NM	Median 24.5 (IQR, 22.3-27.3)	NM
Domicile status	Pre-COVID	Home: 58 (79.45%); residential care: 10 (13.69%); hospital: 5 (6.84%)	Nursing care: 14 (8.04%); own home/sheltered housing: 135 (77.58%); residential care: 25 (14.36%)	NM	NM	NM	NM	NM	NM
	COVID	Home: 61 (80.2%); residential care: 11 (14.47%); hospital: 4 (5.26%)	Nursing care: 8 (11.8%); own home/sheltered housing: 52 (76.5%); residential care: 8 (11.8%)	NM	NM	NM	NM	NM	NM
ASA grade	Pre-COVID	1:2 (2.6%); 2:18 (24%); 3:42 (56%); 4:13 (17.3%); 5:0 (0%)	1:4 (2.29%); 2:53 (30.4%); 3:98 (56.3%); 4:19 (10.9%)	1:0; 2:22 (31.4%); 3:48 (68.6%); 4:0	NM	NM	NM	1 and 2: 22 (25.6%); 3 and 4: 64 (74.4%)	1 and 2: 66 (25.3%); 3, 4 and 5: 195 (74.7%)
	COVID	1:2 (2.6%); 2:12 (15.7%); 3:51 (67%); 4:9 (11.8%); 5:2 (2.6%);	1:0 (0.0%); 2:17 (25.0%); 3:47 (69.1%); 4:4 (5.9%);	1:0; 2: 29 (42.7%); 3:37 (54.4%); 4:2 (2.9%)	NM	NM	NM	1 and 2: 12 (16.2%); 3 and 4: 62 (84%)	1 and 2: 35 (17.2%); 3, 4 and 5: 168 (82.8%)
Anesthesia	Pre-COVID	GA: 51 (69.8%); SA: 22 (30.1%)	NM	NM	NM	GA: 78 (70.3%); SA: 33 (29.7%)	NM	NM	GA: 76 (29.1%); SA/nerve block: 185 (70.9%)
	COVID	GA: 36 (50%); SA: 36 (50%)	NM	NM	NM	GA: 82 (61.2%); SA: 52 (38.8%)	NM	NM	GA: 37 (18.2%); SA/ nerve block: 166 (81.8%)
Time to surgery (h)	Pre-COVID	Median: 20 (IQR, 16-25); 1mean: 20.35 + 6.80	2018: 26.5 ± 18.7; 2019: 28.2 ± 51.7	36 ± 38.4	NM	33.6 ± 19.2	21.8 (range, 8-48)	Median: 16.5 (IQR, 9-30); 1mean 18.61 ± 15.83	< 24 h: 56 (21.4%); 24-48 h: 85 (32.6%); > 48 h: 120 (46.0%)
	COVID	Median: 23 (IQR, 18-30); 1mean: 23.7 ± 9.06	21.8 ± 12.1	43.2 ± 31.2	51.2	33.6 ± 36	35.8 (range, 8.5-79)	Median: 24 (IQR, 24-48); 1mean: 32.46 ± 18.14	< 24 h: 78 (38.4%); 24-48 h: 92 (45.3%); > 48 h: 33 (16.3%)
Fracture type	Pre-COVID	FN: 45 (59.2%); IT: 31 (40.7%)	FN: 101 (58.0%); IT: 66 (37.9%); ST: 7 (4.02%)	NM	NM	FN: 43 (37.4%); IT: 69 (60.0%); ST: 3 (2.6%)	NM	IT: 45 (52.33%); FN: 41 (47.67%)	FN: 266
	COVID	FN: 51 (67.1%); IT: 25 (32.8%)	FN: 44 (64.7%); IT: 21 (30.8%); ST: 3(4.41%)	NM	NM	FN: 71 (51.4%); IT: 60 (43.5%); ST: 7 (5.1%)	NM	FN: 33 (44.59%); IT: 41 (55.41%)	FN: 203
Surgical techniques	Pre-COVID	Nonoperative: 3 (3.9%); DHS: 26 (34.2%); IMN: 9 (11.8%); Hemi A: 31 (40.7%); THA: 7 (9.2%); CRPP: 0 (0%)	THA: 12 (6.8%); Hemi A: 77 (44.2%); CCS: 4 (2.29%); DHS: 48 (27.5%); IMN: 31 (17.8%); Nonoperative: 2 (1.14%)	Operative: 67 (95.7%); nonoperative: 3 (4.3%)	NM	IMN: 61 (54.9%); Hemi A: 22 (19.8%); THA: 10 (9.0%); DHS: 10 (9.0%); CRPP: 8 (7.2%); nonoperative: 4 (3.5%)	All operative (15)	CS: 11 (12.8%); Hemi A: 14 (16.3%); THA: 19 (22.1%); Girdlestone: 1 (1.1%); IMN: 41 (47.7%); nonoperative: 0	Hemi A: 115 (44.1%); DHS: 68 (26%); IMN: 43 (16.5%); THA: 35 (13.4%); conservative: 5 (1.9%)
	COVID	Nonoperative: 3 (3.9%); CRPP: 1 (1.31%); DHS: 14 (18.4%); IMN: 13 (17.1%); Hemi A: 42 (55.2%); THA: 3 (3.9%)	Nonoperative: 2 (2.94%); CCS: 3 (4.41%); DHS: 12 (17.64%); IMN: 11 (16.17%); Hemi A: 39 (57.35%); THA: 1 (1.47%)	Operative: 64 (94.1%); nonoperative: 4 (5.9%)	DHS: -7 (16.27%); CS: 3 (6.9%); Hemi A: 15 (34.8%); IMN: 13 (30.2%); THA: 1 (2.3%); Rev THA: 4 (9.3%)	IMN: 64 (46.3%); Hemi A: 42 (31.3%); THA: 6 (4.5%); DHS: 7 (5.2%); CRPP: 15 (11.2%); nonoperative: 4 (2.9%)	Operative:14; 1 patient expired before surgery	CS: 2 (2.75%); Hemi A: 20 (27%); THA: 10 (13.5%); Girdlestone: 0; IMN: 41 (55.4%); nonoperative: 1 (1.35%)	Hemi A:113 (55.7); DHS: 47 (23.1%); IMN: 36 (17.7%); THA: 7 (3.4%); conservative: 0

¹Indicates that the mean has been calculated from the median value and interquartile range/range. NOS: Newcastle-Ottawa scale; M: Male; F: Female; ASA: American Society of Anesthesiologists Classification; COVID: Coronavirus disease 2019; IQR: Interquartile range; NM: Not mentioned; GA: General anesthesia; SA: Spinal anesthesia; FN: Femoral neck fracture; IT: Intertrochanteric fracture; DHS: Dynamic hip screw; IMN: Intramedullary nail; Hemi A: Hemiarthroplasty; THA: Total hip arthroplasty; CRPP: Closed reduction percutaneous pinning; ST: Subtrochanteric fracture; CS: Cannulated screw; CCS: Cannulated compression screw; Rev THA: Revision total hip Arthroplasty.

Table 3 Mortality and complications in hip-fractured patients treated during coronavirus disease 2019 and pre-coronavirus disease 2019 times (2020)

Study/country		Macey et al[9]/United Kingdom	Malik-Tabassum et al[38]/United Kingdom	Segarra et al[27]/Spain	Thakrar et al[19]/United Kingdom	Egol et al[20]/United States	Williams et al[28]/United Kingdom	Slullitel et al[39]/Argentina	Karayiannis et al[29]/United Kingdom
30-d mortality	Pre-COVID	10 (13%)	12 (6.89%)	9 (12.9%)	6 (6.06%)	3 (2.7%)	1 (6.6%)	0	16 (6%)
	COVID	11 (14%)	6 (8.8%)	8 (11.8%)	7 (16.3%)	17 (12.3%)	2 (13.3%)	8 (10.8%)	7 (3.4%)
	COVID +	2 (20%)	1 (100%)	NM	4 (33%)	9 (52.9%) + 2 (14.3%); Total-11 (35.4%)	NM	NM	4 (57.14%)
	COVID −	9 (13.6%)	5 (7.4%)	NM	3 (9.6%)	6 (5.6%)	NM	NM	3 (42.86%)
In-patient mortality	Pre-COVID	NM	11 (6.32%)	NM	NM	1 (0.9%)	NM	NM	NM
	COVID	NM	4 (5.9%)	NM	NM	8 (5.8%)	NM	NM	NM
Length of hospital stay (d)	Pre-COVID	Median: 12 (range, 7-26); 1mean: 14.25 ± 3.17	2018: 15.8 ± 11.4; 2019: 16.3 ± 11.4	NM	NM	5.8 ± 3.7	11.7	Median: 5 (IQR, 4-7); 1mean: 5.35 ± 2.26	NM
	COVID	Median: 11.5 (range, 6-22); 1mean: 12.75 ± 2.67	8.6 ± 4.6	NM	NM	5.8 ± 3.8	6.2	Median: 6 (IQR, 5-8); 1mean: 6.35 ± 2.26	NM
Major complications	Pre-COVID	11 (14.5%)	17 (9.7%)	NM	NM	10 (8.7%)	NM	10 (11.6%)	NM
	COVID	17 (22.4%)	3 (4.5%)	NM	NM	28 (20.3%)	NM	16 (21.6%)	NM
Pulmonary complications/pneumonia/ respiratory infection	Pre-COVID	8 (10.95%)	NM	NM	NM	NM	2 (13.3%)	2 (2.32%)	NM
	COVID	15 (20.54%)	NM	NM	NM	NM	0	0	NM
Deep vein thrombus/pulmonary embolism	Pre-COVID	1 (1.36%)	2 (1.14%)	NM	NM	NM	NM	0	NM
	COVID	0	1 (1.47%)	NM	NM	NM	NM	5 (6.75%)	NM

¹Indicates that the mean has been calculated from the median value and interquartile range/range. COVID: Coronavirus disease 2019; COVID +: Coronavirus disease 2019 infected; COVID −: Coronavirus disease 2019 non-infected; NM: Not mentioned; IQR: Interquartile range.