Page 182 - Adams and Stashak's Lameness in Horses, 7th Edition
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148 Chapter 2
Quantification of Asymmetry Quantification of Asymmetry
Stride Rate: 1.6 Strides Assessed (fore/hind): 32/32 Stride Rate: 1.6 Strides Assessed (fore/hind): 16/16
Forelimb Strides
Hindlimb Strides
Hindlimb Strides
Forelimb Strides
VetBooks.ir 60 40 Right Fore Lameness –30 Left Hind Lameness Right Hind Lameness 30 20 60 40 Right Fore Lameness –30 Left Hind Lameness Right Hind Lameness 30 20
Pushoff
Pushoff
Pushoff
Pushoff
Midstance
Midstance
–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 10 20 30 0 10 20 30 –60 –40 –20 0 20 40 60 0 5 10 15 0 5 10 15
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: 2.1 mm SD: 6.9 mm Diff Max Pelvis: Mean: 3.3 mm SD: 2.8 mm Diff Max Head: Mean: 5.2 mm SD: 4.1 mm Diff Max Pelvis: Mean: –3.5 mm SD: 3.4 mm
Diff Min Head: Mean: 14.1 mm SD: 7.6 mm Diff Min Pelvis: Mean: –4.6 mm SD: 4.2 mm Diff Min Head: Mean: –8.6 mm SD: 7.3 mm Diff Min Pelvis: Mean: 7.7 mm SD: 4.6 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): 10.0 mm
Q Score (fore): R 14.3 Mid Q Score (hind): R 3.3 Push / L 4.6 Imp Q Score (fore): L 10.0 Push Q Score (hind): L 3.5 Push / R 7.7 Imp
Figure 2.138. Lameness Locator® reports of multiple limb compensatory or secondary multiple limb lameness pattern
lameness. Left report: Right hindlimb pushoff, left hindlimb impact, completely explains this pattern. The best explanation is primary
and right forelimb lameness. Right report: Left hindlimb pushoff, hindlimb lameness, with compensatory ipsilateral forelimb, and
right hindlimb impact, and left forelimb lameness. No simple single secondary contralateral hindlimb lameness exists.
Quantification of Asymmetry Quantification of Asymmetry
Stride Rate: 1.5 Strides Assessed (fore/hind): 28/25 Stride Rate: 1.6 Strides Assessed (fore/hind): 22/22
Forelimb Strides Hindlimb Strides Forelimb Strides Hindlimb Strides
60 Left Hind Lameness Right Hind Lameness 60 Left Hind Lameness Right Hind Lameness
–30 30 –30 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 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 Impact Impact –60 Impact Impact
–60 –40 –20 0 20 40 60 –30 0 10 20 0 10 20 30 –60 –40 –20 0 20 40 60 –30 0 5 10 15 20 0 5 10 15 20 30
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: 6.4 mm SD: 5.2 mm Diff Max Pelvis: Mean: –5.7 mm SD: 3.1 mm Diff Max Head: Mean: –6.4 mm SD: 16.2 mm Diff Max Pelvis: Mean: 10.4 mm SD: 3.7 mm
Diff Min Head: Mean: 7.8 mm SD: 9.5 mm Diff Min Pelvis: Mean: –4.7 mm SD: 3.3 mm Diff Min Head: Mean: –39.2 mm SD: 22.2 mm Diff Min Pelvis: Mean: 6.4 mm SD: 7.5 mm
Threshold for Total Diff Head: 8.5 mm Threshold for Total Diff Head: 8.5 mm
Total Diff Head (Vector Sum): 10.1 mm Total Diff Head (Vector Sum): 39.7 mm
Q Score (fore): R 10.1 Imp Q Score (hind): L 5.7 Push / L 4.7 Imp Q Score (fore): L 39.7 Mid Q Score (hind): R 10.4 Push / R 6.4 Imp
Figure 2.139. Lameness Locator® reports of multiple limb lameness. The best explanation for this type is primary forelimb with
lameness. Left report: Left hindlimb pushoff and impact lameness compensatory contralateral hindlimb pushoff lameness and
and contralateral right forelimb lameness. Right report: Right secondary contralateral hindlimb impact lameness.
hindlimb pushoff and impact lameness and contralateral left forelimb
This type occurred in 17% of multiple limb cases. ness type. The simplest explanation for this type of
A possible explanation of this type of multiple limb multiple limb lameness is primary forelimb with
lameness is primary forelimb lameness with compen compensatory contralateral lack of hindlimb push
satory (or secondary) contralateral hindlimb lack of off. This type of multiple limb lameness had a 70%
pushoff and secondary (to the contralateral lack of definitive diagnosis rate, with 78% ultimately having
hindlimb pushoff) ipsilateral hindlimb impact lame only a forelimb lameness, with about 1 in 5 (22%)
ness. This type of multiple limb lameness had a high being bilateral, 13% having an ultimate diagnosis in
(71%) definitive diagnostic rate, with 66% having a both a forelimb and a hindlimb, and only 4% having
diagnosis only in the forelimbs, with about ¼ (27%) a diagnosis only in the hindlimb. A diagnosis of
being bilateral, 19% having a diagnosis only in the “other,” or an abnormality localized but not in the
hindlimbs, and 13% having a diagnosis in both a limbs, was present in only 4% of cases.
hindlimb and a forelimb. Only about 2% had diag 7. Forelimb lameness with contralateral hindlimb lame
nosis in an area of the body other than in the limbs. ness that is only decreased impact (Figure 2.141).
6. Forelimb lameness with contralateral hindlimb lame This type occurred in less than 10% of cases. No
ness that is only decreased pushoff (Figure 2.140). compensatory‐only pattern can explain this type of
This type occurred in 23% of all multiple limb multiple limb lameness. Equally legitimate explana
cases, which is the most common multiple limb lame tions are primary forelimb lameness and secondary
