Definition of Metrics to Evaluate Cochlear Array Insertion Forces Performed with Forceps, Insertion Tool, or Motorized Tool in Temporal Bone Specimens

Table 1

Metric values recorded during of the cochlear implantation with three different insertion techniques.

Metric	Insertion technique	Mean ± SD	𝑛	𝑃
Peak; (N)	Forceps	0.256 ± 0.061	10	NA
	Hifocus tool	0.327 ± 0.055	8	0.028
	Motorized	0.255 ± 0.075	8	NS
Momentum; (Ns)	Forceps	1.16 ± 0.505	10	NA
	Hifocus tool	1.337 ± 0.408	8	NS
	Motorized	1.573 ± 0.764	8	NS
Over threshold; >0.1 N	Forceps	21.00 ± 12.552	10	NA
	Hifocus tool	7.00 ± 4.036	8	0.002
	Motorized	3.38 ± 3.113	8	0.0002
Sudden rise	Forceps	90.60 ± 46.569	10	NA
	Hifocus tool	28.25 ± 15.872	8	0.0003
	Motorized	14.00 ± 6.949	8	0.00003
Jerk; (N·s^−1)	Forceps	0.467 ± 0.116	10	NA
	Hifocus tool	0.515 ± 0.206	8	NS
	Motorized	0.1553 ± 0.05	8	0.00008

Values are expressed as mean ± SD of 𝑛 insertion. NA: not applicable; NS: not significant. “Forceps” stands for manual insertion with forceps technique, “Hifocus tool” stands for Hifocus 1J electrode insertion tool technique, and “motorized” stands for our in-house motorized insertion tool technique. Statistical analysis was performed by analysis of variance. Each technique was compared against the manual insertion with forceps technique.