Table 2.
Patellar Height Indices of the Skeletally Mature and Immature Groups
| Patellar Height Index | Mean | Standard Deviation | Minimum | Maximum | Range | 95.0% Lower CL for Mean | 95.0% Upper CL for Mean | Standard Error of Mean | Median |
|---|---|---|---|---|---|---|---|---|---|
| Skeletally mature group | |||||||||
| ISI | 1.14 | .17 | .79 | 1.47 | .68 | 1.09 | 1.19 | .02 | 1.15 |
| CDI | 1.02 | .14 | .75 | 1.39 | .63 | .98 | 1.06 | .02 | .99 |
| BPI - 0° | .94 | .14 | .66 | 1.35 | .69 | .91 | .98 | .02 | .92 |
| BPI - 5° | .91 | .13 | .62 | 1.32 | .70 | .87 | .94 | .02 | .89 |
| BPI - 10° | .86 | .13 | .58 | 1.28 | .70 | .82 | .90 | .02 | .86 |
| BPI - 15° | .81 | .13 | .53 | 1.22 | .69 | .78 | .85 | .02 | .82 |
| Skeletally immature group | |||||||||
| ISI | 1.28 | .29 | .76 | 2.30 | 1.54 | 1.19 | 1.36 | .04 | 1.25 |
| CDI | 1.14 | .24 | .62 | 1.85 | 1.23 | 1.07 | 1.20 | .03 | 1.15 |
| BPI - 0° | 1.04 | .24 | .57 | 1.86 | 1.29 | .97 | 1.11 | .03 | 1.03 |
| BPI - 5° | 1.00 | .24 | .54 | 1.72 | 1.18 | .93 | 1.06 | .03 | .98 |
| BPI - 10° | .94 | .22 | .51 | 1.56 | 1.05 | .88 | 1.01 | .03 | .91 |
| BPI - 15° | .88 | .21 | .48 | 1.38 | .90 | .82 | .95 | .03 | .85 |
NOTE. Shown are ISI, CDI, and BPI at 0°, 5°, 10°, and 15°. Normal ranges for each patellar height index: BPI: patella alta >1.06, patella infera <0.54; ISI: patella alta >1.2, patella infera <0.8; CDI: patella alta >1.3, patella infera <0.6.
BPI, Blackburne–Peel index; CDI, Caton–Deschamps index; CL, confidence Limit; ISI, Insall–Salvati index.