Table 3.

Self-directed or asynchronous digital exercise interventions.

Study	Population	Design	Intervention		Comparator or comparators			Primary outcome findings
			Description	Sample size	Description	Sample size
Dahlberg et al [44]	Knee or hip osteoarthritis	Pre or post	Joint Academy (website with videos on education and exercise and asynchronous chat support from PTa)	53	N/Ab	N/A	68% (16/53) of responders defined by individual improvement of >1.5 on the NRSc pain score
Nero et al [45]	Knee or hip osteoarthritis	Observational and quasi-experimental	Joint Academy (website with videos on education and exercise and asynchronous chat support from PT)	350	Published data from in-person PT	—d	Significant improvements in NRS pain score or function on 30-second chair stand test
Allen et al [52]	Knee osteoarthritis	RCTe	IBETf (website with tailored exercise, exercise videos, automated reminders, and progress tracking)	140	In-person PT and waitlist control	140 (in-person) and 70 (waitlist)	No difference between groups for improvements in WOMACg score
Pignato et al [43]	Knee osteoarthritis	Secondary analysis from an RCT [52]	Website	124	In-person PT	135	More PT visits resulted in greater improvement in WOMAC scores
Nelligan et al [42]	Knee osteoarthritis	Participants and assessors blinded RCT	My Knee Exercise website with education+prescription for a 24-week knee strengthening regimen+ automated personalized SMS text messages	103	Access to My Knee Exercise website with education+automated SMS text messages without specific information on exercises	103	Greater improvements in overall knee pain and WOMAC function in the intervention vs comparator
Dahlberg et al [6]	Knee or hip osteoarthritis	Longitudinal cohort study	Joint Academy website with videos on education and exercise and asynchronous chat support from PT	499	N/A	N/A	Improvement in monthly NRS pain score and physical function on 30-second chair stand test at week 12
Gohir et al [53]	Knee osteoarthritis	RCT	Joint Academy website	48	Usual care delivered by a general practitioner or physical therapist	57	Greater improvements in NRS pain score in the intervention vs comparator at 6 weeks
Piqueras et al [51]	Post-KRh	RCT	Asynchronous platform with inertial sensors to measure movement, avatar-based exercise, and web portal for PT	90	In-person PT	91	No difference in knee flexion and extension after the intervention between groups
Bini et al [50]	Post-KR	RCT	Phone app with videos prescribed by PT	14	In-person outpatient PT	15	No difference between groups for VASi, Veterans RAND 12-item health survey mental component and physical component scores, and KOOSj
Chughtai et al [46]	Pre-KR	Pre or post study	Mobile app “PreHab” with prehabilitation program before TKAk	114	Nonusers	362	Shorter length of stay in the hospital and more favorable discharge disposition status in those who used the app
Fleischman et al [49]	Post-KR	Randomized noninferiority trial	Inpatient PT until hospital discharge+web-based unsupervised PT with patient monitoring and communication portal	96	Inpatient PT until hospital discharge+printed PT manual and in-person PT	96 (inpatient) and 97 (in-person)	No difference in change in knee flexion in intervention and comparator at 4-6 weeks or 6-months postop
Klement et al [48]	Post-KR	Retrospective intervention	Web-based self-directed PT—automated emails with exercises	296	In-Person PT+web-based self-directed PT	101	Greater difference in knee flexion, SF-12l physical scores, and KOOS pain but not knee extension or SF-12 mental scores in the intervention vs comparator
Ramkumar et al [47]	Pre-KR	Pre or post	Knee sleeve with inertial sensors+phone app	25	N/A	N/A	Improvements in mobility but not knee flexion or KOOS scores at 3 months after operation

^aPT: physical therapy.

^bN/A: not applicable.

^cNRS: Numeric Pain Rating Scale.

^dNot available.

^eRCT: randomized controlled trial.

^fIBET: Internet-Based Exercise Therapy.

^gWOMAC: Western Ontario and McMaster Universities Osteoarthritis Index.

^hKR: knee replacement.

ⁱVAS: Visual Analog Scale.

^jKOOS: Knee Osteoarthritis Outcome Score.

^kTKA: total knee arthroplasty.

^lSF-12: Short Form-12.