ALP	alkaline phosphatase
BMD	bone mineral density
BMP	bone morphogenetic protein
COL	collagen
ECM	extracellular matrix
ELF	extremely low frequency
ELF-PEMF	extremely low frequency pulsed electromagnetic field
ELF-REMF	extremely low frequency rectangular electromagnetic field
ELF-SEMF	extremely low frequency sinusoidal electromagnetic field
ELF-TEMF	extremely low frequency triangular electromagnetic field
FN	fibronectin
KOOS	knee injury and osteoarthritis outcome score
MMP	matrix metalloproteinase
NPDS	Northwick Park dependency score
OP	surgery
OR	Odds Ratio
OSW	Oswestry disability index
ROM	range of motion
ROS	reactive oxygen species
TGF-β	transforming growth factor beta
UV	ultraviolet
VAS	visual analogue scale
VLF	very low frequency
WOMAC	Western Ontario and McMaster Universities osteoarthritis index