Mechanical lateral distal femoral angle

Mechanical lateral distal femoral angle

  • Acronym: mLDFA

Definition

Stephan Mahler

The mechanical lateral distal femoral angle (mLDFA) is a measurement used to assess angular deformities of the femur and provide guidance for corrections. It is determined from a ventrodorsal radiograph of the hips and femurs or multiplanar reconstructed CT images of the femur. For radiographic acquisition, the dog is placed dorsal recumbency and the pelvic limbs are extended caudally, the femurs are parallel to each other. Positioning is considered satisfactory if :

The mechanical lateral distal femoral angle is measured as the intersecting angle of the mechanical femoral axis in the frontal plane and the proximal femoral joint orientation line.

The following results have been published for mechanical lateral distal femoral angle :

  • Small breeds: 103.1+/-3.4° (Radiography) Olimpo et al. 2016

  • Small breeds: 100° (84-116): (Radiograph) Garnoeva et al. 2018

  • Labrador retriever: 100 +/- 2.6° (radiograph) Tomlinson et al. 2007

  • Golden retriever: 100 +/- 2.3° (Radiography) Tomlinson et al. 2007

  • German shepherd: 97 +/- 3.1° (radiograph) Tomlinson et al. 2007

  • Rottweiler: 100 +/- 2.7° (radiograph) Tomlinson et al. 2007

  • Pomeranian: 99.46 +/- 4° (Radiograph) Soparat et al. 2012

  • Toy poodle: 99.1 +/- 3.1° (Radiograph) Yasukawa et al. 2016

  • Chihuahua: 102.6 +/- 3.1° (Radiography CrCd); 101.6 +/- 3.2 (Radiography CdCr) Phetkaew et al. 2018

  • Chihuahua: 99.9 +/- 3.6° (CT) Phetkaew et al. 2018

  • Poodle toy: 96.2 +/- 2.5° (CT) Yasukawa et al. 2016

  • English bulldog: 101.56 +/- 2.73° (CT) Lusetti et al. 2017

References

  • Garnoeva, R, Roydev, R, Paskalev, M et al. Radiographic measures of pelvic limb malalignment in small breed dogs with various grades of medial patellar luxation. Comp Clin Pathol 2018;27, 1551–1555. doi.org/10.1007/s00580-018-2772-8.

  • Lusetti F, Bonardi A, Eid C, Brandstetter de Belesini A, Martini FM. Pelvic limb alignment measured by computed tomography in purebred English Bulldogs with medial patellar luxation. Vet Comp Orthop Traumatol. 2017 May 10;30(3):200-208. doi: 10.3415/VCOT-16-07-0116. Epub 2017 May 5.

  • Olimpo M, Piras LA, Peirone B. Pelvic limb alignment in small breed dogs: a comparison between affected and free subjects from medial patellar luxation. Vet Ital. 2016 Jan-Mar;52(1):45-50. doi: 10.12834/VetIt.71.206.3.

  • Phetkaew T, Kalpravidh M, Penchome R, Wangdee C. A Comparison of Angular Values of the Pelvic Limb with Normal and Medial Patellar Luxation Stifles in Chihuahua Dogs Using Radiography and Computed Tomography. Vet Comp Orthop Traumatol. 2018 Feb;31(2):114-123. doi: 10.3415/VCOT-17-05-0067. Epub 2018 Mar 13. Erratum in: Vet Comp Orthop Traumatol. 2018 Feb;31(2):a1.

  • Soparat C, Wangdee C, Chuthatep S, Kalpravidh M. Radiographic measurement for femoral varus in Pomeranian dogs with and without medial patellar luxation. Vet Comp Orthop Traumatol. 2012;25(3):197-201. doi: 10.3415/VCOT-11-04-0057. Epub 2012 Jan 27.

  • Tomlinson J, Fox D, Cook JL, Keller GG. Measurement of femoral angles in four dog breeds. Vet Surg. 2007 Aug;36(6):593-8. doi: 10.1111/j.1532-950X.2007.00309.x.

  • Yasukawa S, Edamura K, Tanegashima K, Seki M, Teshima K, Asano K, Nakayama T, Hayashi K. Evaluation of bone deformities of the femur, tibia, and patella in Toy Poodles with medial patellar luxation using computed tomography. Vet Comp Orthop Traumatol. 2016;29(1):29-38. doi: 10.3415/VCOT-15-05-0089. Epub 2015 Dec 7.