Adherence to the Dutch recommendation for physical activity: prior to and after primary total hip and knee arthroplasty

Figures & data

Figure 1. Flowchart patient selection. Included patients with data at all assessments. THA: total hip arthroplasty; TKA: total knee arthroplasty; OA: osteoarthritis; PA level: physical activity level; FU: follow-up.

A flowchart to describe the inclusion of either total hip or knee arthroplasty patients in this study. Only patients with preoperative physical activity levels and follow up at 6 and 12 months postoperatively were included.

Table 1. Preoperative characteristics of patients based on preoperative adherence to the Dutch PA recommendation^a.

	THA		TKA
	Adherent (n = 497)	Non-adherent (n = 508)	Adherent (n = 465)	Non-adherent (n = 507)
Sex, female (%)	281 (56.5)	323 (63.6)	274 (58.9)	334 (65.9)
Age (years) (mean (SD))	68.0 (8.3)	68.2 (9.1)	67.0 (8.2)	67.4 (8.0)
BMI (mean (SD))	26.6 (3.8)	27.7 (4.4)	28.4 (4.3)	30.2 (5.1)
Smoking, yes (%)	18 (3.6)	21 (4.1)	22 (4.7)	25 (4.9)
Missing (%)	99 (19.9)	101 (19.9)	85 (18.3)	87 (17.2)
Comorbidities (%)
Non-musculoskeletal	145 (29.2)	162 (31.9)	161 (34.6)	166 (32.7)
Musculoskeletal	63 (12.7)	59 (11.6)	57 (12.3)	43 (8.5)
Both	163 (32.8)	196 (38.6)	128 (27.5)	180 (35.5)
None	67 (13.5)	45 (8.9)	67 (14.4)	59 (11.6)
Missing	59 (11.9)	46 (9.1)	52 (11.2)	59 (11.6)
HOOS/KOOS scores (mean (SD))
Symptoms	42.3 (18.9)	40.0 (17.7)	51.3 (17.7)	48.5 (17.8)
Pain	41.2 (18.3)	37.4 (17.9)	40.4 (17.5)	38.0 (16.6)
ADL	44.8 (19.2)	39.2 (18.2)	48.8 (18.0)	43.4 (17.7)
Sport and recreation	23.6 (21.0)	16.5 (17.0)	12.9 (15.8)	10.5 (14.6)
Quality of life	32.1 (15.7)	27.2 (16.2)	28.8 (15.0)	25.2 (14.6)
Living arrangement (%)
Alone	95 (19.1)	102 (20.1)	80 (17.2)	106 (20.9)
With others	365 (73.5)	375 (73.8)	347 (74.6)	356 (70.2)
Missing	37 (7.4)	31 (6.1)	38 (8.2)	45 (8.9)
SF-12 scores (mean (SD))
MCS	55.1 (9.6)	53.3 (10.3)	55.9 (9.0)	54.7 (9.8)
PCS	34.2 (9.2)	30.8 (9.1)	34.7 (9.5)	30.7 (8.8)
Work
Paid job, yes (%)	135 (27.2)	110 (21.7)	135 (29.0)	125 (24.7)
Missing	3 (0.6)	2 (0.4)	5 (1.1)	1 (0.2)
PA recommendation (days) (mean (SD))	6.2 (0.9)	1.8 (1.5)	6.3 (0.9)	2.0 (1.5)

THA: total hip arthroplasty; TKA: total knee arthroplasty; n: number of patients; SD: standard deviation; BMI: body mass index; HOOS: The Hip Disability and Osteoarthritis Outcome Score; KOOS: The Knee Injury and Osteoarthritis Outcome Score; MCS: mental component summary of the short-form-12; PCS: physical component summary of the short-form-12.

All continuous variables are depicted as mean (SD).

^a The Dutch recommendation for health enhancing physical activity.

Figure 2. Possible postoperative (at 6 and 12 months) physical activity trajectories of total hip arthroplasty patients that either adhered or not-adhered to the physical activity guideline prior to surgery, resulting in eight possible trajectories for adherence at 12 months. ^aa: All percentages are with respect to preoperatively meeting the PA recommendation. Complete cases: patients with data at both 6 and 12 months postoperative.

Figure 3. Possible postoperative (at 6 and 12 months) physical activity trajectories of total knee arthroplasty patients that either adhered or not-adhered to the physical activity guideline prior to surgery, resulting in eight possible trajectories for adherence at 12 months. ^aa: All percentages are with respect to preoperatively meeting the PA recommendation. Complete cases: patients with data at both 6 and 12 months postoperative.

Table 2. Associated predictors (preoperative and 6 months after surgery) for adherence 12 months after surgery.

	Total hip arthroplasty population		Total knee arthroplasty population
	Adherent (n = 497) ^a OR [95%CI]	Non-adherent (n = 508) ^a OR [95%CI]	Adherent (n = 465) ^a OR [95%CI]	Non-adherent (n = 507) ^a OR [95%CI]
6-month follow-up model
Age	–	–	1.03 [1.00–1.06]	1.03 [1.00–1.05]
BMI	1.07 [1.02–1.15]	–	1.06 [1.00–1.12]	1.08 [1.03–1.12]
Comorbidities	–		–	–
Musculoskeletal comorbidities (yes)		2.33 [0.96–5.68]
Non-musculoskeletal comorbidities (yes)		1.03 [0.50–2.14]
Both types of comorbidities (yes)		1.69 [0.80–3.57]
MCS	–	–	–	0.97 [0.95–0.99]
Preoperative work status	–	0.48 [0.29–0.80]	–	–
Preoperative HOOS/KOOS subscales	–
Pain		–	0.99 [0.96–1.02]	–
ADL		0.99 [0.98–1.01]	0.99 [0.96–1.02]	–
Symptoms		1.02 [1.00–1.03]	1.03 [1.01–1.05]	–
Quality of life		–	–	1.02 [1.00–1.03]
6-month FU HOOS/KOOS subscales
Pain	0.99 [0.97–1.00]	–	–	–
ADL	–	0.99 [0.97–1.00]	–	0.99 [0.98–1.00]
Quality of life			0.99 [0.98–1.00]	–
Meeting 6-month PA recommendation	0.16 [0.10–0.27]	0.23 [0.15–0.35]	0.22 [0.13–0.36]	0.29 [0.19–0.42]

OR: odds ratio; 95%CI: 95% confidence interval; BMI: body mass index; HOOS: The Hip Disability and Osteoarthritis Outcome Score; KOOS: The Knee Injury and Osteoarthritis Outcome Score; MCS-12: mental component summary of the short-form-12.

Multivariable logistic regression with imputed values and backward elimination; if a variable was identified as a predictor for that time point and population, an odds ratio and corresponding 95% confidence interval is included.

^a Stratification based on meeting the PA recommendation prior to total hip or knee arthroplasty surgery; this was coded as event.

Bold values indicating statistical significant OR.

Data availability statement

The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.