Table V.

Reoperation-free survival by intraarticular intervention and Tönnis Grade

Tönnis Grade 0
Reoperation-free survival (cumulative incidence)
Time (years)	Major (95% CI)	Minor (95% CI)	No intervention (95% CI)	Overall (95% CI)
1	100% (100–100)	95.5% (87.1–100)	96.2% (91.1–100)	96.6% (93.6–100)
2	95% (85.9–100)	95.5% (87.1–100)	93.8% (87.2–100)	94.5% (89.9–99.3)
Cox proportional hazards ratio
Major (95% CI)	Major P-value	Minor (95% CI)	Minor P-value	No intervention
0.45 (0.05–4.02)	0.47	1.97 (0.44–8.86)	0.38	Reference
Tönnis Grade 1
Reoperation-free survival (cumulative incidence)
Time (years)	Major (95% CI)	Minor (95% CI)	No intervention (95% CI)	Overall (95% CI)
1	100% (100–100)	87.5% (67.3–100)	93.3% (81.5–100)	95.7% (89.9–100)
2	92.9% (80.3–100)	87.5% (67.3–100)	76.4% (56–100)	86.1% (75.3–98.5)
Cox proportional hazards ratio
Major (95% CI)	Major P-value	Minor (95% CI)	Minor P-value	No intervention
0.47 (0.08–2.63)	0.39	1.25 (0.22–7.06)	0.80	Reference