Table 3.

Three stages of classification.^a

	Stage I	Stage II	Stage III
ADLs	Unable to stand ≥ 15 minutes Unable to sit ≥ 30 minutes Unable to walk ≥ 1/4 mile	Exceeds all ADL criteria of stage I Difficulty with basic functional ADLs (ie, vacuuming, lifting)	Able to perform basic functional ADLs Cannot participate fully in sport
Typical modified ODI scores	≥ 20%	≤ 20%	≤ 20%

^aAdapted from Delitto et al²¹ and Brennan et al.¹¹ ADL, activity of daily living; ODI, Oswestry Disability Index.