Table 2.

Summary of electromagnetic Field (EMF) Application to In Vivo and In Vitro Cartilage Explants and Scaffolds.

Study Model	Chondrocytes Isolation Source	Frequency (Hz)	EMFs	Stimulation Time	Effect on Cell Proliferation	Effect on Matrix Synthesis	Reference
In vivo	Knee of Hartley guinea pigs	1.5	1.0 G	1 hour/day for 6 months	Articular cartilage morphology was preserved. The EMF retarded the development of osteoarthritic lesions		Ciombor et al.28
In vivo	Joint knee from Hartley guinea pigs	75	1.5 mT	6 hours a day for 3 months	The EMFs preserve the morphology of articular cartilage and the thickness of the medial tibia plateaus		Fini et al.61
In vitro	Femoral condyles of human knee	10, 100, 370, 500	0.74, 0.85, 1.69, 3.14, 5.42 (mT peak)	6 h	Magnetic field strengths of 1.7 and 3.1 mT peak with frequencies of 500 and 100 Hz maintained chondrocyte spherical morphology		Jahns et al.29
In vitro	Human articular cartilage chondrocytes	75	2.3 mT	1, 6, 9, and 18 hours	—	9- and 18-hour stimulation leads to increased DNA and PG synthesis	De Mattei et al.36
In vitro	Porcine articular cartilage	5 pulses of 100 ns	10 or 20 kV/cm	1, 3, and 7 days	Significantly increase in cell proliferation	A decrease in glycosaminoglycan, collagen II, Sox9, and aggrecan gene expression was observed	Zhang et al.30
In vitro (cartilage explant)	Metacarpophalangeal joints of bovine	75	1.5 mT	24 hours	—	20% increase in proteoglycan synthesis	De Mattei et al.42
In vitro (cartilage explant)	Metacarpophalangeal joints of bovine	75	2.3 mT	24 hours	—	EMFs are able to promote anabolic activities and proteoglycan synthesis	De Mattei et al.47
In vitro (osteoarthritic cartilage explants)	Human femoral condyles	75	1.6 mT	4 hours daily for 4 days	Increment in DNA content	No changes in glycosaminoglycans were evidenced	Sadoghi et al.40
In vitro (3-dmensional culture)	Human chondrocytes cultured in a type-I collagen gel	16.7	2 mT	1, 3, 7, and 14 days	—	Positive staining for collagen II and proteoglycan in the immediate pericellular region	Schmidt-Rohlfing et al.43
In vivo (growth plate)	Male albino Wistar rats	900 and 1800 MHz	—	12 weeks	Stimulated rats experienced a more rapid weight gain and increase in length. Rats showed a loss in in the reserve zone, with an increase in thickness in the proliferative zone		Nisbet et al.67
In vivo (growth plate)	Right hind limb of a rabbit	—	1.5 mT	10 minutes per day over 15 days	EMFs exert a suppressive influence on chondrocyte proliferation	—	Arsen’ev et al.68