Table 2.

Grade of recommendation for each mode of electrical stimulation for each type of bone healing diagnosis based on Oxford Centre Level of Evidence Recommendation.

	Level of Recommendation
Direct current
Spinal fusion	B
Ankle/foot union	C
Osteonecrosis of the femoral head	B
Nonunion	C
Capacitive coupling
Spinal fusion	A
Nonunion	C
Pulsed electromagnetic field
Spinal fusion	A
Ankle/foot union	C
Osteonecrosis of the femoral head	C
Nonunion	C
Osteotomy	B
Fresh fracture	B
Congenital pseudoarthrosis	C

DC indicates direct current; CC, capacitive coupling; PEMF, pulsed electromagnetic field.