Table 3.

The ability of acoustic emissions and kinematic instability (AUC > 0.600) to detect specific osteoarthritic changes in females.

Signal	Medial joint space narrowing (no = 34/yes = 32)	Lateral joint space narrowing (no = 59/yes = 7)	Medial femoral osteophytes (no = 51/yes = 15)	Medial tibial osteophytes (no = 30/yes = 36)	Lateral femoral osteophytes (no = 57/yes = 9)	Lateral tibial osteophytes (no = 40/yes = 26)
Age						p = 0.004
BMI	p = 0.009		p = 0.003	p < 0.001	p < 0.001	p = 0.001
AE medial extension ratio (hf and lf)
AE medial extension ratio (hf and cl)	p = 0.032		p = 0.040	p = 0.001	p = 0.043	p = 0.001
AE lateral extension ratio (hf and lf)	p = 0.032					p = 0.015
AE lateral extension ratio (hf and cl)						p = 0.039
AE lateral flexion kurtosis (hf)
AE lateral flexion skewness (lf)
AE medial sit-to-stand ratio (hf and lf)
AE medial sit-to-stand ratio (hf and cl)	p = 0.006			p = 0.007
AE medial sit-to-stand kurtosis (lf)
AE medial sit-to-stand skewness (lf)
AE lateral sit-to-stand skewness (hf)		p = 0.039				p = 0.013
AE lateral sit-to-stand kurtosis (all)		p = 0.007				p = 0.018
AE lateral sit-to-stand kurtosis (lf)
AE lateral sit-to-stand skewness (all)		p = 0.003				p = 0.022
AE lateral sit-to-stand skewness (lf)
Kinematic instability			p = 0.002	p < 0.001	p = 0.018	p = 0.001

The absence or presence of osteoarthritic changes on conventional radiography are given in parentheses (no/yes), and corresponding statistically significant p-values for each biomarker.

AE acoustic emission, BMI body mass index, hf high frequency, lf low frequency, cl clicks, all high and low frequency.