Medium-term efficacy of arthroscopic debridement vs conservative treatment for knee osteoarthritis of Kellgren-Lawrence grades I-III

Table 1 Baseline data in the two groups

Variable	Group A	Group B	t-value	χ2 value	P value
Number of patients	98	80
Age (yr), mean ± SD	59.27 ± 14.48	58.75 ± 14.66	-0.235	-	0.815
Female/male	74/24	60/20	-	0.006	0.937
BMI, mean ± SD	24.60 ± 2.74	24.92 ± 2.68	0.776	-	0.439
Side of KOA (left/right)	44/54	36/44	-	0.000	0.989
Kellgren-Lawrence grade
1	26	23	-	0.109	0.742
2	22	19	-	0.042	0.838
3	50	38	-	0.218	0.640
HSS score before treatment, mean ± SD	78.65 ± 11.20	79.10 ± 11.41	0.263	-	0.793

Statistical difference between the two groups was tested by t test or χ² analysis. Statistical significance was set at P < 0.05. SD: Standard deviation; BMI: Body mass index; KOA: Knee osteoarthritis; HSS: American hospital for special surgery knee score; Group A: Arthroscopic debridement group; Group B: Conservative treatment group.