Page 181 - Adams and Stashak's Lameness in Horses, 7th Edition

Examination for Lameness 147

Quantification of Asymmetry Quantification of Asymmetry
Stride Rate: 1.6 Strides Assessed (fore/hind): 22/21 Stride Rate: 1.6 Strides Assessed (fore/hind): 19/19
Forelimb Strides
Forelimb Strides
Hindlimb Strides
Hindlimb Strides
VetBooks.ir 60 40 Right Fore Lameness –30 Left Hind Lameness Right Hind Lameness 30 20 60 Right Fore Lameness –30 Left Hind Lameness Right Hind Lameness 30 20
Pushoff
Pushoff
Pushoff
Pushoff
Midstance
Midstance
40
–20
–20
20 Pushoff Impact – Diff Max (mm) –10 10 + Diff Max (mm) 20 Pushoff Impact – Diff Max (mm) –10 10 + Diff Max (mm)
Diff Min (mm) 0 0 0 Diff Min (mm) 0 0 0
–20 –10 10 –20 –10 10
Pushoff Impact Pushoff
Impact
–40 Midstance – Diff Min (mm) –20 20 + Diff Min (mm) –40 Midstance – Diff Min (mm) –20 20 + Diff Min (mm)
Left Fore Lameness Left Fore Lameness
–60 –30 Impact Impact 30 –60 –30 Impact Impact 30
–60 –40 –20 0 20 40 60 0 5 10 15 20 0 5 10 15 20 –60 –40 –20 0 20 40 60 0 5 10 15 20 0 5 10 15 20
Diff Max (mm) Stride Stride Diff Max (mm) Stride Stride
Lameness Metrics Lameness Metrics
Thresholds for Max/Min Head: ±6 mm Thresholds for Max/Min Pelvis: ±3 mm Thresholds for Max/Min Head: ±6 mm Thresholds for Max/Min Pelvis: ±3 mm
Diff Max Head: Mean: 10.2 mm SD: 5.8 mm Diff Max Pelvis: Mean: 11.7 mm SD: 3.3 mm Diff Max Head: Mean: –12.8 mm SD: 12.4 mm Diff Max Pelvis: Mean: –11.6 mm SD: 5.2 mm
Diff Min Head: Mean: 10.0 mm SD: 7.2 mm Diff Min Pelvis: Mean: 3.2 mm SD: 4.5 mm Diff Min Head: Mean: –13.3 mm SD: 6.1 mm Diff Min Pelvis: Mean: –0.8 mm SD: 5.8 mm
Threshold for Total Diff Head: 8.5 mm Threshold for Total Diff Head: 8.5 mm
Total Diff Head (Vector Sum): 14.3 mm Total Diff Head (Vector Sum): 18.4 mm
Q Score (fore): R 14.3 Imp Q Score (hind): R 11.7 Push / R 3.2 Imp Q Score (fore): L 18.4 Imp Q Score (hind): L 11.6 Push / L 0.8 Imp
Figure 2.136. Lameness Locator® reports of multiple limb forelimb lameness. These are examples of the first part of the law
lameness. Left report: Right hindlimb pushoff only, no impact of sides: primary hindlimb lameness with compensatory (false)
lameness, and ipsilateral (right) forelimb lameness. Right report: ipsilateral forelimb lameness.
Left hindlimb pushoff only, no impact lameness, and ipsilateral (left)
Quantification of Asymmetry Quantification of Asymmetry
Stride Rate: 1.4 Strides Assessed (fore/hind): 39/39 Stride Rate: 1.5 Strides Assessed (fore/hind): 27/27
Forelimb Strides Hindlimb Strides Forelimb Strides Hindlimb Strides
60 –30 Left Hind Lameness Right Hind Lameness 30 60 –30 Left Hind Lameness Right Hind Lameness 30
Pushoff Pushoff Pushoff Pushoff
Right Fore Lameness Right Fore Lameness
40 Midstance –20 20 40 Midstance –20 20
Pushoff Impact – Diff Max (mm) + Diff Max (mm) Pushoff Impact – Diff Max (mm) + Diff Max (mm)
20 –10 10 20 –10 10
Diff Min (mm) 0 0 0 Diff Min (mm) 0 0 0
–20 –10 10 –20 –10 10
Pushoff Impact Pushoff
Impact
–40 – Diff Min (mm) + Diff Min (mm) –40 – Diff Min (mm) + Diff Min (mm)
Midstance –20 20 Midstance –20 20
Left Fore Lameness Left Fore Lameness
–60 –30 Impact Impact 30 –60 –30 Impact Impact 30
–60 –40 –20 0 20 40 60 0 10 20 30 40 0 10 20 30 40 –60 –40 –20 0 20 40 60 0 10 20 0 10 20
Diff Max (mm) Stride Stride Diff Max (mm) Stride Stride
Lameness Metrics Lameness Metrics
Thresholds for Max/Min Head: ±6 mm Thresholds for Max/Min Pelvis: ±3 mm Thresholds for Max/Min Head: ±6 mm Thresholds for Max/Min Pelvis: ±3 mm
Diff Max Head: Mean: 3.0 mm SD: 7.5 mm Diff Max Pelvis: Mean: 0.0 mm SD: 4.5 mm Diff Max Head: Mean: –8.0 mm SD: 6.4 mm Diff Max Pelvis: Mean: 0.4 mm SD: 2.6 mm
Diff Min Head: Mean: 12.5 mm SD: 8.3 mm Diff Min Pelvis: Mean: 5.2 mm SD: 2.6 mm Diff Min Head: Mean: –21.6 mm SD: 7.7 mm Diff Min Pelvis: Mean: –12.1 mm SD: 4.4 mm
Threshold for Total Diff Head: 8.5 mm Threshold for Total Diff Head: 8.5 mm
Total Diff Head (Vector Sum): 12.8 mm Total Diff Head (Vector Sum): 23.0 mm
Q Score (fore): R 12.8 Mid Q Score (hind): R 0.0 Push / R 5.2 Imp Q Score (fore): L 23.0 Imp Q Score (hind): R 0.4 Push / L 12.1 lmp
Figure 2.137. Lameness Locator® reports of multiple limb explained by either the first or second part of the law of sides, either
lameness. Left report: Right hindlimb impact only, no pushoff a primary hindlimb lameness with compensatory ipsilateral forelimb
lameness, and ipsilateral (right) forelimb lameness. Right report: lameness or primary forelimb lameness with compensatory
Left hindlimb impact only, no pushoff lameness, and ipsilateral (left) ipsilateral hindlimb impact lameness.
forelimb lameness. This multiple limb pattern can be equally
hindlimb diagnosis, 11% had both a forelimb and a A complicated explanation of primary hindlimb
hindlimb diagnosis, and 45% had only a forelimb lameness, with compensatory ipsilateral forelimb
diagnosis, about 1/3 being a bilateral forelimb lame­ lameness, and secondary contralateral hindlimb lack
ness condition. Also, a relatively high percentage of impact lameness is required to fully explain this
(9%) of these cases had diagnosis of abnormality not pattern. However, this type of multiple limb lameness
located within the limbs. When seeing this type of had a relatively high rate (71%) of definitive diagno­
multiple limb lameness, it was equally likely for the sis, with 35% ultimately diagnosed with only a
primarily lameness to be in the forelimb or in the hindlimb problem, 25% with both a hindlimb and
hindlimb. forelimb problem, 20% with only a forelimb problem
4. Forelimb lameness with ipsilateral hindlimb lame­ (but bilateral in 100%), and 20% with a non‐limb
ness that is decreased pushoff and contralateral diagnosis. This type of multiple limb lameness pattern
hindlimb lameness that is decreased impact had the highest percentage of “other” diagnosis
(Figure 2.138). (problem found but not in the limbs).
This type occurred rarely. It was seen in only 4% 5. Forelimb lameness with contralateral hindlimb lame­
of all multiple limb cases. There is no easy, compensa­ ness that is decreased pushoff and decreased impact
tory‐ or secondary‐only explanation of this pattern. (Figure 2.139).