Is there a weekend effect after hip fracture surgery? A study of 74,410 hip fractures reported to the Norwegian Hip Fracture Register

Figures & data

Figure 1. Patient selection.

Table 1. Baseline characteristics for all patients with separate numbers for day of fracture and day of surgery. Values are frequency (%)

	Day of fracture			Day of surgery
Characteristics	Weekday	Weekend	p-value ^a	Weekday	Weekend	p-value ^a
Total (76,410)	55,406	21,004		54,558	21,852
Age category			0.003			< 0.001
	60–74	9,603 (17)	3,873 (19)		9,464 (17)	4,012 (18)
	75–79	7,873 (14)	2,950 (14)		7,717 (14)	3,106 (14)
	80–84	12,536 (23)	4,569 (22)		12,247 (23)	4,858 (22)
	85–89	14,272 (26)	5,399 (26)		14,087 (26)	5,584 (26)
	≥ 90	11,122 (20)	4,213 (20)		11,043 (20)	5,584 (20)
Female sex	39,452 (71)	14,978 (71)	0.3	38,817 (71)	15,513 (71)	0.3
ASA classification			0.1			0.001
	1	2,300 (4.2)	941 (4.5)		2,251 (4.1)	990 (4.5)
	2	18,839 (34)	7,195 (34)		18,518 (34)	7,516 (34)
	3	30,367 (55)	11,472 (55)		29,901 (55)	11,938 (55)
	4	3,818 (6.9)	1,369 (6.5)		3,804 (7.0)	1,383 (6.3)
	5	82 (0.1)	27 (0.1)		84 (0.2)	25 (0.1)
Cognitive impairment			0.2			0.01
	No	35,472 (64)	13,398 (64)		34,698 (64)	14,172 (65)
	Yes	13,687 (25)	5,313 (25)		13,704 (25)	5,296 (24)
	Uncertain	5,252 (9.5)	1,938 (9.2)		5,189 (9.5)	2,001 (9.2)
	Missing	995 (1.8)	355 (1.7)		967 (1.8)	383 (1.8)
Type of fracture			0.7			0.6
	Undisplaced FNF	8,168 (15)	3,063 (15)		8,104 (15)	3,127 (14)
	Displaced FNF	22,679 (41)	8,752 (42)		22,396 (41)	9,035 (41)
	Basocervical FNF	2,004 (3.6)	718 (3.4)		1,952 (3.6)	770 (3.5)
	Trochanteric
	AO/OTA A1	9,414 (17)	3,552 (17)		9,250 (17)	3,716 (17)
	AO/OTA A2	8,829 (16)	3,309 (16)		8,651 (16)	3,487 (16)
	AO/OTA A3	940 (1.7)	349 (1.7)		923 (1.7)	366 (1.7)
	Subtrochanteric	2,906 (5.2)	1,079 (5.1)		2,833 (5.2)	1,152 (5.3)
	Other	466 (0.8)	182 (0.9)		449 (0.8)	199 (0.9)

a Pearson’s chi-square test.

FNF = femoral neck fracture.

Table 2. Operative data with separate numbers for day of fracture and day of surgery. Values are frequency (%)

	Day of fracture			Day of surgery
Characteristics	Weekday	Weekend	p ^a	Weekday	Weekend	p ^a
Total (76,410)	55,406	21,004		54,558	21,852
Surgeon’s experience level ^b			0.5			1.0
	< 3 years	4,680 (16)	1,789 (16)		4,612 (16)	1,857 (16)
	≥ 3 years	22,375 (79)	8,591 (79)		22,085 (79)	8,881 (79)
	Missing	1,450 (5.1)	522 (4.8)		1,407 (5.0)	565 (5.0)
Time from fracture to operation			< 0.001			< 0.001
	0–6 hours	2,579 (4.7)	1,197 (5.7)		2,614 (4.8)	1,162 (5.3)
	> 6–12 hours	9,266 (17)	3,441 (16)		9,200 (17)	3,507 (16)
	> 12–24 hours	20,190 (36)	7,807 (37)		19,414 (36)	8,583 (39)
	> 24–48 hours	15,970 (29)	5,675 (27)		15,628 (29)	6,017 (28)
	> 48 hours	7,401 (13)	2,884 (14)		7,702 (14)	2,583 (12)
Type of primary operation			0.7			0.2
	Screw osteosynthesis	10,968 (20)	4,246 (20)		10,862 (20)	4,352 (20)
	Hemiprosthesis	19,734 (36)	7,524 (36)		19,452 (36)	7,776 (36)
	Sliding hip screw	11,712 (21)	4,408 (21)		11,493 (21)	4,627 (21)
	Sliding hip screw + TSP	5,021 (9.1)	1,863 (8.9)		4,855 (8.9)	2,029 (9.3)
	Short IM nail	4,604 (8.3)	1,710 (8.1)		4,535 (8.3)	1,779 (8.1)
	Long IM nail	2,371 (4.3)	896 (4.3)		2,383 (4.4)	884 (4.0)
	Other	996( 1.8)	357 (1.7)		948 (1.7)	405 (1.9)

a Pearson’s chi-square test.

b Registered since 2011.

TSP = trochanteric support plate; IM = intramedullary.