Table 2.

Quantitative characteristics of PEEK-based particles produced using clinically relevant joint replacement simulators

Study	Joint	Bearing couples	Feret’s diameter (µm)	ECD (µm)	Range (µm)	AR	E	R	FF
Brown et al. [5]	L.Disc	PEEK/PEEK (UD) PEEK/PEEK (MD)	0.87 2.00	0.69 1.09	–	1.36 1.42	–	0.79 0.75	0.89 0.88
Grupp et al. [12]	C.Disc	UHMWPE/CoCr PEEK/PEEK CRF-PEEK (Pan)/CRF-PEEK (Pan) PEK/PEK	0.13–0.24 0.23–0.51 0.27–0.35 1.0–1.5	–	0.01 to 1-15 0.01 to 1-15 0.01 to 1-15 0.2–50	–	–	–	–
Grupp et al. [15]	UKR	UHMWPE/CoCr CRF-PEEK (Pitch)/CoCr CRF-PEEK (Pan)/CoCr	0.72 ± 0.99 1.27 ± 5.18 0.98 ± 1.75	–	–	1.77 ± 0.94 1.69 ± 0.81 1.65 ± 0.65	3.89 ± 2.88 3.46 ± 2.21 3.12 ± 1.61	0.54 ± 0.21 0.58 ± 0.22 0.61 ± 0.24	0.55 ± 0.14 0.57 ± 0.12 0.59 ± 0.11
Grupp et al. [13]	TKA*	CFR-PEEK (Pan)/ZrN CFR-PEEK (Pan)/CoCr	1.89 ± 2.54 0.82 ± 1.80	–	0.05 to 3-20 0.05 to 3–20	1.47 ± 0.48 1.70 ± 0.72	2.23 ± 1.60 3.29 ± 2.52	0.64 ± 0.17 0.58 ± 0.22	–

^*Only the bushings and flanges within this device were manufactured out of CFR-PEEK; each column represents a mean value; PEEK = polyetheretherketone; L.Disc = lumbar disc; C = disc, cervical disc; UKA = unicompartmental knee arthroplasty; UD = unidirectional motion; MD = multidirectional motion; CoCr = cobalt chromium alloy; ZrN = zirconium nitride; ECD = equivalent circle diameter; AR = aspect ratio; E = elongation ratio; R = roundness; FF = form factor.