Table 2.

Differences in VAS score and WOMAC index (mean ± SD) between patients treated with HA or controls at baseline before and after propensity score (PS) adjustment.

Comparison	Not adjusted difference	Difference after PS adjustment
Hyaluronic acid 1,500–3,200 kDa vs. controls
Pain VAS	−1.3 ± 4.8 (p = 0.783)	−6.4 ± 4.8 (p = 0.187)
WOMAC index
Total	8.2 ± 4.5 (p = 0.07)	2.7 ± 4.3 (p = 0.537)
Pain	2.0 ± 1.1 (p = 0.07)	0.9 ± 1.1 (p = 0.435)
Stiffness	1.4 ± 0.5 (p = 0.008)	0.7 ± 0.4 (p = 0.071)
Function	4.3 ± 3.5 (p = 0.216)	1.1 ± 3.4 (p = 0.746)
HYLAN G-F 20 vs. NSAIDs
Pain VAS	1.8 ± 3.7 (p = 0.638)	−5.1 ± 4.0 (p = 0.201)
WOMAC index
Total	10.3 ± 3.4 (p = 0.002)	2.6 ± 3.5 (p = 0.466)
Pain	2.5 ± 0.9 (p = 0.006)	0.9 + 1.0 (p = 0.376)
Stiffness	1.2 ± 0.5 (p = 0.009)	0.3 ± 0.3 (p = 0.320)
Function	6.6 ± 2.6 (p = 0.013)	1.3 ± 2.8 (p = 0.634)