Well with less than 6 weeks until Christmas, I have finally found some time in the diary to write another website blog! Once again, it has been a busy few months for the whole Waterside Chiropractic crew. As I sit writing this the weather outside is again wet…like it has been for most of the last two weeks, but then I suppose it is November! The ground is covered in leaves from the last few days of strong winds. Just walking Merlot and Sol up at Eartham Woods yesterday made me think more about the surfaces that we exercise our beloved equine and canine partners on. Obviously with dogs, they are not carrying a rider so there are less forces involved in the foot-surface interaction. Nonetheless, changes to the interaction of the foot and surface can have significant effects on performance, the conditioning of the musculoskeletal tissues and the risk of injury.
Soundness and performance are the main focus in most discussions of riding surfaces. Lameness and back pain are the most common problems requiring veterinary care and leading to loss of use in equestrian sport. Whether a horse is sound of course depends on an intricate combination of internal (often innate) factors such as breeding, conformation, age, training history and previous injury plus external factors such as training and surface use. When it comes to soundness external risk factors are much easier to influence than internal risk factors.
The mechanical interaction of the equine limb and the ground is influenced by various factors; fore-hind mass distribution, lead limb, moving on a curve, shoeing and surface properties (Parkes & Witte, 2015). As the trainers of our horses, we need to expose them to a variation of surfaces; grass, concrete, tarmac, hillside tracks and various manege surfaces such as sand, rubber, fibre, etc., in order to strengthen the bone, tendons and musculature of the whole body, not just the limbs. Horses worked on only one type of surface are more likely to experience injury when exposed to a different type of surface and injury is fundamentally linked to the interaction of the horse with the ground and surface. Early studies of racehorses (Thoroughbreds and Standardbreds) implicate harder ground or going with an increased risk of injury compared with softer ground (Cheney et al, 1973; Parkin, 2008); however we now know that the picture is affected by the type of injury more likely to be sustained. The risk of distal limb fracture and tendon injuries may increase on firmer ground but softer ground is associated with a greater risk of falling, which may be linked to the deeper ground increasing muscular fatigue (Butcher et al, 2007).
Parkes & Witte (2015) reviewed surface-related factors and injury, taking into account over 100 previous studies. It should not be forgotten that in addition, the horse’s conformation, the shape of the hoof, barefoot or shod, all influence the hoof-ground interaction and the forces acting on the limb. However, in this blog we are only going to give consideration to surfaces.
When discussing surfaces in relation to performance and reducing injury risk it is important to remember that the way a surface is used is as important as to which surface is used. Scientific research on race and sport horse orthopaedic injuries has found that the risk of injury differs between yards/riders/trainers (Hernlund, 2014). Studies have also shown that training and surface use interact to influence injury risk. Dressage horses that regularly train on a surface that becomes deep in wet weather are more likely to sustain injuries than horses training on a firmer surface (Murray et al, 2010).
Training variation means riding on a variety of surfaces! This includes using more than one type of arena, but especially riding on varied natural terrain, (quiet) roads and other types of bridleway or paths. The body of the horse adapts to the surface used. If the horse is constantly ridden on the same surface the musculoskeletal system is not prepared for any variations, thereby increasing the risk of injury. Surfaces can also be used as a part of a training regimen aimed at promoting soundness. British riders have a tradition of roadwork, with gradually increased distances of walk and trot on roads/tarmac. There is one school of thought that road work strengthens the musculoskeletal system; there is another that too much road work causes concussive injuries such as splints and windgalls. As with everything, as part of a gradual, balanced and varied conditioning programme on a variety of surfaces it will develop a better conditioned horse that will have less risk of fatigue and thus less risk of injury.
The main points in relation to different types of surfaces are as follows:
1) Hard ground (concrete/tarmac/sun-baked ground) – magnifies the concussive forces as it absorbs very little of the energy. There is normally a reduction in stride length, the swing and stance phase of the stride, foot flight arc and moment of suspension. There is an increased risk of injury to bones, joints and cartilage; however, walking and short bursts of trot can improve bone density.
2) Soft ground (some arenas or maneges, clay soils, beach) – there is a significant reduction in the concussive forces but conversely, the muscles need to work harder to enable recoil of the limb and takes more energy. There can be a risk of increased soreness, injury and tendon/ligament strain.
3) Hillwork – improves cardiovascular fitness, endurance and general strength. Strengthens your horse’s topline, builds gluteal and hindlimb musculature, improves balance, co-ordination and proprioception. A good all rounder for your horse, both uphill and downhill!
4) Water – moving through water not only strengthens the muscles during the swing phase of the stride, it encourages the horse to lift his feet and strengthens the abdominal and core musculature, improving posture and performance. It also provides therapeutic cooling of the legs (depending on how deep the water is!) Obviously, it also depends on what the surface is under the water (beach, XC course, flooded roads, etc.)
Last but by no means least, as a chiropractor I also think that it is also important to consider the symmetry and musculoskeletal alignment of your horse. No skeleton or musculoskeletal framework is completely symmetrical but if you or your horse are significantly asymmetric, this can also affect performance and increase the risk of injury. Not only does an asymmetric rider affect the horse and vice versa, both will need to compensate for the other’s asymmetry causing additional forces to affect the body, resulting in imbalance and uneven wear and tear throughout the limbs and body and development of the musculoskeletal system. Horses will always move in the way that is most comfortable and easiest for them, unintentionally but repeatedly strengthening already strong muscles and further weakening the weaker ones. Get yourself and your horse checked out regularly by an experienced chiropractor to make sure that you are both as straight and as symmetric as possible, so that you both can achieve optimum movement, posture and performance, whilst reducing your risk of pain and injury. Contact Waterside Chiropractic for further information and an informal discussion on 07738 110570.
Sources
Butcher MT, Hermanson JW, Ducharme NG, Mitchell LM, Soderholm LV, Bertram JEA (2007) Superficial digital flexor tendon lesions in racehorses as a sequela to muscle fatigue: a preliminary study – Equine Vet J; 39, 540-545
Cheney JA, Shen CK & Wheat JD (1973) Relationship of racetrack surface to lameness in the Thoroughbred racehorse – Am J Vet Res; 34, 1285-1289
Hernlund E (2014) Equestrian Surfaces – A Guide – FEI, Swedish Equestrian Federation & the Swedish University of Agricultural Sciences
Murray RC, Walters JM, Snart H, Dyson SJ, Parkin TD (2010) Identification of risk factors for lameness in dressage horses – Vet J; 184, 27-36
Parkes RSV & Witte TH (2015) The foot-surface interaction and its impact on musculoskeletal adaptation and injury risk in the horse – Equine Vet Journal; 47 (5), 519-525
Parkin TD (2008) Epidemiology of racetrack injuries in racehorses – Vet Clinic N Am: Equine Pract; 24, 1-19