Initial Assessment: 2) Dynamic
Carrying on from last week's post, after static assessment, I like to watch the animal move,
we call this dynamic assessment. This blog should hopefully give you an idea of what I am looking for as I ask you to trot up and down with your animal!
Dynamic assessment is about observing how the animal moves and deciphering how this may be linked to their case history, static and palpation assessment.
I like to watch the horse or dog in a straight line, on a hard surface, in walk and trot. Lunging may be included if more subtle lamenesses and movements need to be picked up, as demonstrated by the love Winnie below.
When watching the horse walk or trot towards me, I am looking out for certain gait characteristics such as how they hold their head- which may indicate lameness; limb movement characteristics such as whether the horse swings the leg outwards or inwards when stepping forward, how well the joints flex, where the animal places their hoof/paw and rotation of the hoof/paw when it is in contact with the ground. See if you can spot any of this in the video of Molly below!
From behind I will look at similar characteristics in the hindlimbs, as well as watching for hindlimb lameness and tail movement. Finally, when watching from the side, I will often look at features such as whether they brace their back or neck when moving, indicating uncomfortableness; stride length and flight arc (how they carry their limb through a step). For example, a short and choppy stride can be an indicator of many musculoskeletal pathologies such as tightness in the Trapezius, Superficial Pectoral or Deltiodeous muscle, as well as others. Little Molly in the video below is getting old and suffers from many of the problems above, can you see how choppy her stride looks?
Whereas Caper in the video below is a young, relatively healthy dog. He shows such ease in his trot and stride:
Moreover, differences in stride lengths and times of one limb compared to the opposite limb can be an indicator of lameness, as the animal spends longer walking on the sound limb compared to the lame limb. Furthermore, the animal may be observed to land heavier on the sound limb compared to the lame one, which can even be audibly heard in horses.
As touched on above, certain movements can also indicate problems or tightness in specific muscles. For example a tilting of the head and poor contact in one rein in a horse may be due to issues in an important muscle in the back called the Longissimus Dorsi. Or a shortened stride in the hindlimb may be due to issues with the Biceps Femoris (hamstring) or Gastrocnemius (calf) muscle.
Dynamic assessments may also be moved to different surfaces as they aggravate different issues. For example, a hard surface, such as concrete has high impact and will exacerbate ‘bony’ pathologies such as osteoarthritis (like Molly in the video above). Whereas a soft surface, such as sand in a school, has more give- thus testing soft tissue injuries such as tendon and ligaments. Different movements such as lunging, circles, rein back, walking and trotting also cause varying forces on specific tissues and structures. Therefore, these other disciplines will also be assessed.
This is not an exhaustive list, but just a number of features I look for when dynamically assessing your horse or dog. This brings me onto the third step in the initial assessment: palpation- which I will be explaining in my next post!