Table 2.

Summary of the recent studies on the effects of mechanical loading on hMSCs in a 3D scaffold.

Bioreactor	Loading Regime	Scaffold	Pore Size	Medium Supplementation	Osteogenesis	Cell Source/Differentiation Status before Mechanical Loading	Ref.
Compression	0.22–1.1%, 1 Hz, 4 h/ day for 4 weeks	Polycaprolactone-β tricalcium phosphate (β-TCP)	-	Dexamethasone + β-glycerophosphate	↑ ALP	Bone marrow/undifferentiated	Ravichandran et al. 2017 [26]
					↑ ON
					↑ OCN
					↑ Mineral deposit
Compression	0.4%, 0.1 Hz, 2 h/day for 1 day	Monetite calcium phosphate	200–650 μm	None	↑RUNX2	Bone marrow/undifferentiated	Gharibi et al. 2013 [60]
Compression	5–20%, 1 Hz, 2 h/day for 4 weeks	Polycaprolactone	-	Dexamethasone + β-glycerophosphate	↓ ON	Bone marrow/undifferentiated	Horner et al. 2018 [71]
					↓ Calcium deposit
Compression	5–10%, 1 Hz, 9 h/day for 6 days	Collagen	64–93 μm	None	↓RUNX2	Bone marrow/undifferentiated	Schreivogel et al. 2019 [72]
					↓ OCN
Perfusion	3 mL/min (0.2 dyn/cm2) for 2 weeks; oscillatory flow	Hyaluronic acid–poly(lactide-co-glycolide) (PLGA)	300 μm	Dexamethasone + β-glycerophosphate	↑ OCN	Bone marrow/undifferentiated	Mitra et al. 2017 [8]
					↑ Calcium deposit
					↑ BSP (in vivo)
					↑ Bone volume fraction (ratio of bone volume to total tissue volume)
					Host tissues were integrated into both the cell-laden and cell-free scaffolds
Perfusion	1 mL/min (0.161 dyn/cm2) for 3 weeks; unidirectional flow	Decellularized porcine bone construct	250–400 μm	Dexamethasone + β-glycerophosphate	↑RUNX2	Bone marrow and fat/undifferentiated	Wu et al. 2015 [44]
					↑ OPN
					↑ OCN
					↑ Calcium deposit
					Bone marrow MSCs > adipose MSCs (↑ RUNX2, ↑ OPN, ↑ ALP and ↑ Calcium deposit)
Perfusion	Steady flow (0.045 dyn/cm2, 2 weeks) + pulsatile flow (0.045–0.134 dyn/cm2, 0.5 Hz, 4 h/day for 3 weeks)	Silk fibroin	400–600 μm	Dexamethasone + β-glycerophosphate	↑ OPN	Fat/osteogenic differentiated (precultured in osteogenic induction medium for 3 days)	Correia et al. 2013 [45]
					↑ BSP
					↑ Young’s modulus of the bone grafts from 150 kPa to 270 kPa
					↑ Bone volume fraction
Perfusion	4.2 dyn/cm2, 2 h/day for 2 weeks; intermittent unidirectional flow	PLGA	280–450 μm	None	↑RUNX2	Bone marrow/undifferentiated	Liu et al. 2014 [61]
					↑ ALP
					↑ OCN
Perfusion	2.5 mL/min (0.0679 dyn/cm2) for 2 h; unidirectional flow	Gelatine-coated polyurethane	334 μm	Dexamethasone + β-glycerophosphate	↑RUNX2	Bone marrow/early and late osteogenic differentiated (precultured in osteogenic induction medium for 7 and 15 days, respectively)	Filipowska et al. 2016 [73]
					↑ OPN
					↑ OCN
Perfusion	0.3 mL/min (0.0123 dyn/cm2) for 3 weeks; oscillatory flow	Cancellous bone powder	200–800 μm	Dexamethasone + β-glycerophosphate	↑RUNX2	Bone marrow/undifferentiated	Le Pape et al. 2018 [74]
					↑ ALP
Perfusion	100 μm/s (0.493 dyn/cm2) for 3 weeks; oscillatory flow	PLGA	100–150 μm	Dexamethasone + β-glycerophosphate	↑ ALP	Bone marrow/undifferentiated	Moser et al. 2018 [75]
					↑ OPN
					↑ OCN
Perfusion	1.5 mL/min (0.0182 or 0.0097 dyn/cm2) for 3 weeks; unidirectional flow	β-TCP	750 and 1400 μm	Dexamethasone + β-glycerophosphate	750 μm > 1400 μm (↑ ALP and ↑ OPN)	Bone marrow/undifferentiated	Bernhardt et al. 2011 [76]
Perfusion	4.2 dyn/cm2 (2 h/day) + 0.34 dyn/cm2 (22 h/day) for 2 weeks; intermittent rapid unidirectional flow	PLGA	280–450 μm	Dexamethasone + β-glycerophosphate	↑RUNX2	Bone marrow/undifferentiated	Liu et al. 2011 [77]
					↑ ALP
					↑ OCN
Vibration	30 nm amplitude, 1000 Hz for 7 days	Collagen gel	-	None	↑ OSX	Bone marrow/undifferentiated	Tsimbouri et al. 2017 [28]
					↑ ALP
					↑ OPN
					↑ OCN