Table 1.
Results of taking radiographic images at 70° to 20° by changing the knee flexion angle at 10° intervals using Development of patellofemoral joint radiography auxiliary device (PJR).
| PJR used | Measures | ||||||
|---|---|---|---|---|---|---|---|
| Parameters | 70° | 60° | 50° | 40° | 30° | 20° | p-Value |
| Degree of flexion | |||||||
| Patellar angle | 18° | 15° | 12° | 9° | 6° | 4° | — |
| X-ray tube angle | 108° | 105° | 102° | 99° | 96° | 94° | — |
| Detector angle | 72° | 75° | 78° | 81° | 84° | 86° | — |
| (a) DMLP | 11.27 ± 0.16 | 10.69 ± 0.23 | 10.24 ± 0.23 | 9.97 ± 0.15 | 9.95 ± 0.1 | 9.95 ± 0.1 | 0.001 |
| (b) DPFG | 11.16 ± 0.71 | 11.59 ± 0.68 | 9.41 ± 0.36 | 12.35 ± 0.67 | 10.1 ± 0.53 | 8.28 ± 0.65 | 0.001 |
| (c) DFGT | −4.14 ± 0.16 | −5.47 ± 0.2 | −5.75 ± 0.17 | −0.37 ± 0.36 | 2.5 ± 0.32 | 4.87 ± 0.26 | 0.001 |
DMLP = the distance between the line connecting the medial and lateral sides of the patella and the lowest point of the median ridge of the patellar, which was measured to evaluate patellar inclination. DPFG = the patellofemoral joint space distance. DFGT = the distance between the femoral trochlear groove and the tibial tuberosity, which was measured to evaluate the degree of overlap between the two bones.