Table 1.

Patellar-height indices.

Index	Patella infera	Patella norma	Patella alta
Insall-Salvati	<0.8	0.8–1.2	>1.2
Modified Insall-Salvati	<1.2	1.2–2.0	>2.0
Caton-Deschamps	<0.6	0.6–1.2	>1.2
Blackburne-Peel	<0.6	0-6 – 1.0	>1.0