Radiographic measurement for femoral varus in Pomeranian dogs with and without medial patellar luxation

Summary

Objectives: To measure radiographically the inclination angle (ICA), femoral varus angle (FVA), anatomical lateral distal femoral angle (aLDFA), and mechanical lateral distal femoral angle (mLDFA) in Pomeranian dogs with and without medial patellar luxation (MPL).

Materials and methods: Stifles of 34 Pomeranian dogs were graded and allocated into three groups: normal, grades I-II MPL, and grade III MPL. Angle values were measured from craniocaudal radiographs of the hindlimbs by each of the three examiners on three separate occasions.

Results: Each of the three groups consisted of 15 stifles. Means ± SD for the ICA, FVA, aLDFA and mLDFA in the normal stifles were 136.46 ± 7.12°, 5.85 ± 3.18°, 95.21 ± 3.48° and 99.46 ± 4°, respectively. No significant differences (p >0.05) in the measured values for the ICA between groups were observed. The FVA, aLDFA and mLDFA values in grade III MPL group were significantly (p <0.05) greater than those in the other two groups. Significant differences in the three angles between the normal and grades I-II MPL groups were not observed.

Clinical significance: Significant change of distal femoral varus exists in Pomeranian dogs with grade III MPL.

Keywords

Femoral varus - Pomeranian dog - patellar luxation - dog

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