Posterior and anterior tilt increases the risk of failure after internal fixation of Garden I and II femoral neck fracture

Figures & data

Figure 1. Flowchart of patient selection.

Table 1. Characteristics of patients (n = 417)

Age^a	78 (10)
Women^b	285 (68)
Cognitive impairment^b	165 (40)
Sheltered housing^b	153 (37)
Preoperative tilt^a	10° (10)
Missing^b	0
Postoperative tilt^a	5° (8)
Missing^b	5 (4)
Implant angulation^a	141° (7)
≤ 125°^b	7 (2)
> 125°^b	399 (96)
Missing^b	11 (3)

a Mean (SD).

b n (%).

Figure 2. Diagram displaying the distribution of patients and treatment failure (n = 417).

Table 2. Treatment failures and reoperations

	< –10°(n = 9)	–10° to 20°(n = 348)	> 20° (n = 60)
Age^a	80 (4)	78 (10)	78 (10)
Women^b	8 (89)	242 (70)	35 (58)
Failure^b	5 (56)	35 (10)	13 (22)
Type of failure, n
Fixation failure	2	8	6
Nonunion	1	7	2
Avascular necrosis (AVN)	2	18	5
Posttraumatic osteoarthritis	0	2	0
Reoperation^b	5 (56)	49 (14)	15 (25)
Type of reoperation, n
Removal of osteosynthesis	0	16	3
Hemiarthroplasty	3	6	4
Total hip arthroplasty	2	17	7
Revision osteosynthesis	0	2	0
Peri-implant fracture	0	6	1
Girdlestone	0	2	0

a Mean (SD).

b n (%).

Figure 3. Plot of the risk of treatment failure. Anterior tilt corresponds to negative values on the X-axis. Adjusted for sex, sheltered housing, cognitive impairment, implant angulation, and postoperative tilt. Light blue area corresponds to 95% CI.

Table 3. Cox proportional hazard model for covariates associated with treatment failure adjusted for sex, sheltered housing, cognitive impairment, implant angulation, and postoperative tilt

Variable	Crude	Adjusted
	HR (2.5%–97.5%)	HR (2.5%–97.5%)
Age	1.0 (1.0–1.0)	1.0 (1.0–1.1)
Sex
Female	1.0 Ref.	1.0 Ref.
Male	0.7 (0.3–1.3)	0.6 (0.3–1.3)
Sheltered housing:
No	1.0 Ref.	1.0 Ref.
Yes	0.5 (0.2–1.0)	0.4 (0.2–1.1)
Cognitive impairment:
No	1.0 Ref.	1.0 Ref.
Yes	0.7 (0.4–1.4)	0.9 (0.4–2.0)
Implant angulation	1.0 (1.0–1.0	1.0 (1.0–1.0)
Preoperative tilt:
–20°	5.8 (1.7–19)	7.9 (1.8–35)
–10°	2.9 (1.4–6.3)	3.6 (1.4–9.3)
0°	1.5 (1.1–2.1)	1.6 (1.1–2.5)
10°	1.0 Ref.	1.0 Ref.
20°	1.5 (1.2–2.0)	1.5 (1.1–2.1)
30°	3.3 (1.7–6.4)	3.4 (1.6–7.3)
40°	7.0 (2.4–21)	7.5 (2.2–25)
Postoperative tilt	1.0 (1.0–1.0)	1.0 (1.0–1.1)

HR = hazard ratio; n = 417.