Table 2.
Results from studies in total knee arthroplasty
| Study, country | Sample characteristics | Assessment timepoint | PA assessment method and outcome measures | Results | Other outcomes and results |
|---|---|---|---|---|---|
| Schotanus et al,27 the Netherlands | N=20; 35% female, 66 years old, BMI: 28.5 kg/m2 | 4 days preop and 6 weeks postop | Activity monitor: Triaxial accelerometer (GC Dataconcepts LLC, Waveland, MS, USA) - Daily time spent in PA (eg, walking, cycling, and standing) and number of steps - Weartime: 4 days PRO: none |
Time spent in PA decreased 25%: 43.5% of 24 h preop and 32.5% postop (p≥.05). Number of steps decreased 35%: 7,600 steps preop and 4,900 steps postop (p<0.05) | Physical function (OKS, WOMAC), general health (EQ-5D), and pain There were improvements in physical function (p<0.05), general health (p<0.05), and pain (p<0.05) |
| Walker et al,30 UK | N=19; 53% female, 69 years old, BMI: not reported | 4 weeks preop and 3 and 6 months postop | Activity monitor: Numact (Newcastle University, Newcastle upon Tyne, UK) - Daily ambulatory EE and number of steps - Weartime: 1 day PRO: NHP - Self-reported EE |
3 months: ambulatory EE increased 29% (p≥0.05) – raw data not provided. Number of steps increased 15% (p≥0.05) – raw data not provided 6 months: ambulatory EE increased 79% (p=0.01) – raw data not provided. Number of steps increased 46% (p=0.01) – raw data not provided 3 months: Self-reported EE improved 63%: 49.8 points preop and 18.7 points postop (p<0.05) 6 months: self-reported EE improved 61%: 49.8 points preop and 19.6 points postop (p<0.05) |
Pain, mobility, emotional reaction, social isolation, and sleep (NHP) Pain decreased (p<.05). Mobility improved only at 3 months (p<0.05). Emotional reaction and social isolation improved only at 6 months (p<0.05). Sleep did not change (p≥0.05) |
| Brandes et al,28 Germany | N=53; 64% female, 66 years old, BMI: 30.7 kg/m2 | 3 weeks preop and 2, 6, and 12 months postop | Activity monitors: ADL monitor (McRoberts) and the step activity monitor (OrthoCare Innovations) - Daily number of steps and time spent in locomotion - Weartime: 7 days PRO: none |
2 months: number of steps decreased 6%: 9,986 steps/day preop and 9,460 steps/day postop (p≥0.05). Time spent in locomotion increased 17%: 8.4 h preop and 9.8 h postop (p≥0.05) 6 months: number of steps increased 10%: 9,986 steps/day preop and 10,992 steps/day postop (p=0.03). Time spent in locomotion increased 43%: 8.4 h preop and 12 h postop (p<0.01) 12 months: number of steps increased 19%: 9,986 steps/day preop and 11,864 steps/day postop (p=0.003). Time spent in locomotion increased 43%: 8.4 h preop and 12 h postop (p<0.01) |
Physical function (KSS) and quality of life (SF-36) Physical function and quality of life improved at all follow-ups (p<0.001) |
| Lutzner et al,29 Germany | N=221; 57% female, 68 years old, BMI: 31.3 kg/m2 | Time preop not specified and 12 months postop | Activity monitor: ActivePAL (PAL Technologies) - Total daily number of steps, number of steps at moderate-intensity, and time being sedentary - Weartime: 4 days PRO: none |
Total daily number of steps increased 23%: 5,371 steps/day preop and 6,587 steps/day postop (p=0.001) Number of steps at moderate intensity increased 60%: 1,149 steps/day preop and 1,835 steps/day postop (p=0.001). Daily time in sedentary activities (ie, lying, sitting, and standing) decreased 2%: 106% of 24 h preop and 77% of 24 h postop (p≥0.203) | Knee and physical function (KSS) Knee and physical function improved (p<0.001) |
| Tsonga et al,31 Greece | N=52; 100% female, 73 years old, BMI: 29.8 kg/m2 | Time preop not specified and 3 and 6 months postop | Activity monitor: SW2000 Digiwalker Yamax (FIT Solutions Inc., San Diego, CA, USA) - Daily number of steps - Weartime: 7 days PRO: PASE - PA score |
Number of steps increased 31% from 3 to 6 months: 2,693 steps/day at 3 months postop and 3,518 steps/day at 6 months postop (p<0.001) 3 months: 33% increase in PA score: 43.3 points preop and 57.6 points postop (p≥0.05) 6 months: 57% increase in PA score: 43.3 points preop and 67.9 points postop (p<0.001) |
Quality of life (SF-36) Quality of life improved at both timepoints (p<0.001) |
| de Groot et al,17 the Netherlands | N=44; 55% female, 62 years old, BMI=32.1 kg/m2 | Average of 43 days preop and 3 and 6 months postop | Activity monitor: sensors on thighs and trunk (Temec Instruments) - Movement-related activities - Weartime: 2 days PRO: PASIPD - PA score |
3 months: 11% increase in movement-related activities: 8.1% of 24 h preop and 9% of 24 h postop (p=0.18) 6 months: 12% increase in movement-related activities: 8.1% of 24 h preop and 9.1% of 24 h postop (p=0.06) 3 months: 45% increase in PA score: 9.5 points preop and 13.8 points postop (p=0.13) 6 months: 88% increase in PA score: 9.5 points preop and 17.9 points postop (p<0.01) |
Chair rising test, 6-minute walk test; Pain (WOMAC) and physical function (WOMAC and SF-36) Chair rising test improved at 6 months (p=0.04) but not at 3 months (p=0.19) 6-minute walk test, pain, and physical function improved at all time points (p<0.01) |
| Harding et al,18 Australia | N=25; 64% female, 69 years old, BMI=32 kg/m2 | Time preop not specified and 6 months postop | Activity monitor: ActiGraph GT1M (ActiGraph LLC) - Counts per minute - Weartime: 7 days (minimum of 4 days of data) PRO: UCLA activity score - PA score |
Activity counts decreased 13%: 183 counts/min preop and 159 counts/min postop (p=0.06) PA score increased 67%: 3 points preop and 5 points postop (p<0.001) |
Pain (pain scale) and physical function (OHK score) and quality of life (SF-12) Pain, physical function, and quality of life improved (p≤0.001) |
| Smith et al,16 USA | N=116; 59% female, 67 years old, BMI=30.1 kg/m2 | Time preop not specified and 12 and 24 months postop | Activity monitor: none PRO: PASE - PA score |
12 months: PA score decreased 4%: 126 points preop and 121 points postop (p=0.93) 24 months: PA score increased 13%: 126 points preop and 142 points postop (p=0.04) |
None |
Notes: UCLA activity score: University of California, Los Angeles; a 10-point activity scale that evaluates activities based on 10 descriptive activity levels ranging from wholly inactive and dependent (level 1) to regular participation in impact sports such as jogging or tennis (level 10).20,21 PASIPD: Physical Activity Scale for Individuals with Physical Disabilities; a 13-item self-report questionnaire that captures PA in three areas: recreation, household, and occupational activities. Its score is the average hours per day for each item multiplied by a metabolic equivalent (MET) value associated with the intensity of each activity. Scores range from 0.0 MET-h/day (not performing any activities) to 199.5 MET-h/day (performing all of the listed activities for the maximum amount of days and hours).22,23 PASE: physical activity scale for the elderly; a 12-item scale that assesses PA level of the past 7 days in three domains: recreational, household, and work-related activities. For each activity, a score is obtained by multiplying activity frequency by a task-specific weight provided by the scoring manual. PASE total score is the sum of all activities together and ranges between 0 and 400 or more.24–26 NHP: Nottingham Health Profile; composed of 38 items divided into six domains (sleep, mobility, energy, pain, emotional reactions, and social isolation). Each item is weighted, and scores are calculated by averaging the domain scores. Total scores range from 0 (no perceived distress) to 100 (maximum perceived distress). The domain used to measure self-reported PA is “energy”.32
Abbreviations: PA, physical activity; BMI, body mass index; PRO, patient-reported outcome; EQ-5D, EuroQol-5-Dimension Health Questionnaire; OHK, Oxford Hip and Knee Score; EE, energy expenditure; OKS, Oxford Knee Score; KSS, Knee Society Score; ADL, activities of daily-living; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index; preop, preoperative; postop, postoperative.