Patella Alta
(Redirected from Patella alta)
Other Names
- Patella Alta
- High Riding Patella
Introduction
- Characterized by an abnormally high patella in relation to the femur
- Best seen and measured on Lateral knee radiograph
- It may be idiopathic or pathologic, most classically associated with patellar tendon rupture
Measurement
- Caton-Deschamps index (CDI): > 1.2 to > 1.3
- Insall Salvati Index (ISI): > 1.2
- Blackburne-Peel index (PBI): > 1.0
- Patellotrochlear index (PTI): < 0.125 to 0.28.6,26
Pathology
- Patellar Tendon Rupture
- Patellofemoral Pain Syndrome
- Idiopathic Retropatellar Pain[3]
- Patellar Dislocation[4]
- Chondromalacia Patellae
- Knee Joint Effusion
- Spastic Cerebral Palsy[5]
- Patellar Instability
Evidence
- Ng et al using the insall-salvati ratio[6]
- Sensitivity: 84%
- Specificity: 79%
See Also
References
- ↑ Ishiguro, Yoshitaka, and Akira Kuriyama. "Patella Alta." New England Journal of Medicine 388.24 (2023): e77.
- ↑ Case courtesy of M Mourits, Radiopaedia.org, rID: 14476
- ↑ Kannus, P. A. "Long patellar tendon: radiographic sign of patellofemoral pain syndrome--a prospective study." Radiology 185.3 (1992): 859-863.
- ↑ Ali, Syed A., Robert Helmer, and Michael R. Terk. "Patella alta: lack of correlation between patellotrochlear cartilage congruence and commonly used patellar height ratios." American Journal of Roentgenology 193.5 (2009): 1361-1366.
- ↑ Lotman, D. Barry. "Knee flexion deformity and patella alta in spastic cerebral palsy." Developmental Medicine & Child Neurology 18.3 (1976): 315-319.
- ↑ Ng, Jonathan P., et al. "Focal intratendinous radiolucency: A new radiographic method for diagnosing patellar tendon ruptures." The Knee 23.3 (2016): 482-486.