EFFECTS OF CHRONIC INJURY II
Muscle and limb injuries in greyhounds are the most common cause for downtime from training or lost racing days, accounting for up to 85% of all conditions requiring a rest or lay off from racing.
Injuries to the hip support muscles on the upper right hind leg are a common cause of low grade pain state because of the high loading imposed on these upper right hind limb muscle group when cornering to the left at speed.
This type of muscle sprain and low grade soreness is aggravated each time the greyhound is raced on the particular track, especially a track with a shifting surface on the corners and poor banking.
The greyhound loses form and has a succession of less than optimum performances, dropping back in the field if raced regularly when carrying this type of chronic injury.
Chronic Pain State
Many authorities believe that a sore greyhound develops a chronic pain state which affects it physiologically as well as mentally. The animal becomes stressed by the continuous low grade discomfort of the injury, which is often aggravated by repeated racing at 7-10 day intervals.
Some believe that the affected greyhound anticipates the pain resulting from galloping hard around a corner and is likely to ease off in speed to slow up on the corner when the pain is aggravated by the high speed centrifugal forces when cornering.
Many affected greyhounds lose form and drop down in grading without any outward signs of chronic pain except when checked thoroughly within 6-8 hours after a race.
Walking during recovery after a race does not aggravate the pain from the chronic injury. Some greyhounds are unable to cope with training and develop a ‘trained off, ‘sour ‘ attitude, with a dull coat and lack of vitality for a few days after each race.
It can take up to 7 days for the greyhound to regain its vigour, which is short lived once it faces the cycle of pain during and following the next race.
Trainers become unhappy with the greyhound’s form and loss of chasing keenness, which leads to repeated poor performance by the greyhound and frustration in the trainer if the greyhound’s previous good form is not regained despite rest and routine short term physiotherapy and massage.
Physiological changes
There is evidence that the chronic pain state leads to a number of physiological changes. Blood tests may reveal an increase in circulating adrenal gland corticoid compounds, which are the natural inflammatory reactive hormones which is some cases, leads to an adrenal exhaustion-like syndrome.
This is associated with an increased risk of electrolyte imbalances, associated dehydration, lack of appetite and interest in food, reluctance to exercise and a gradual decline in form.
Greyhounds carrying a chronic injury to muscles, joints or bones, will often develop a dried-out dull coat, lack keenness to race or race inconsistently, putting in one good performance occasionally after being rested for 3-4 weeks between races.
They often suffer chronic dehydration, with symptoms of being ‘tucked up in the belly’, dry coat and mouth membranes, reduced desire to drink because of the loss of fluids and electrolytes.
A repeated blood test to monitor these changes often indicates a chronic depletion of blood potassium levels over a period of time and other associated electrolyte imbalances.
It is important to recognise the early warning signs of a chronic muscle injury. Ideally, a greyhound should race as often as possible when “fit” and “in form” and not be in any discomfort so that it has every chance to win.
Careful Observation when Racing
Many experienced trainers are able to recognise possible muscle injuries by a slight reduction in performance, the way the greyhound jumps from the start, corners, gallops up the home straight, or pulls up.
Even an injured greyhound is often able to gallop so fast that it is hard to see minor changes in direction or “drift out” on corners.
However, a couple of replays of the race video will often help provide vital information on the general area of injury and in a slow replay, it is even easier.
Often, low grade soreness is overlooked, or not given sufficient time to heal before the greyhound is galloped in a hand-slip, trial or race.
Greyhounds with poor conformation also tend to suffer more muscle injuries. Some may “throw” the right hind leg when galloping, making it almost impossible to power themselves cleanly out of the bend.
I had an opportunity to help in the kennels of a friend in Boston USA a few years ago. The kennels housed 270 racers split up between 3 kennel rooms. The kennel contracted to provide 30 racers per day to the local track.
This resulted in many of the greyhounds being raced suffering low grade injuries because of the contract to supply greyhounds regardless of their pain state.
I recollect that there were many greyhounds which had symptoms of a chronic pain state, with dehydration and loss of appetite and electrolyte abnormalities. The reduction in prize money was a problem for the trainer because many greyhounds were running poorly and dropping down in grade based on performance.
The gradual loss of greyhounds which were unable to win or to be placed, resulted in the kennels being closed and the greyhounds reallocated to other race tracks.
Other Factors Influencing Performance
Other factors, such as too much bodyweight, particularly in larger greyhounds, and inadequate fitness also make a greyhound more susceptible to injury. Generally, greyhounds above 33 kg have a higher risk of breakdown when racing.
Stress Pathways
The “stress pathways” of the front and back limbs on each side will need a thorough check.
The deltoid and triceps group of the front leg and the whip and vastus area of the left hind are the major sore spots in straight line deviations. The stress pathways of the right side shoulder and upper hind leg should be checked in a greyhound which runs wide on the bends.
After a week or so of reduced training and occasional lead exercise which helps maintain muscle strength, most minor injuries will be hard to detect, and therefore the best advice may not be able to be given regarding treatment.
Rehabilitation
There are 3 main steps in rehabilitation from a chronic pain state with dehydration and gradual loss of form.
Firstly, identify the location of the injury with a thorough muscle and limb examination by your vet. I normally prefer to check a greyhound out within 12 hours of a race as many greyhounds will still exhibit discomfort in the key muscle stress pathways of the front and hind limbs.
It is important to fully assess the greyhound’s physical state and if possible collect blood for a potassium and electrolyte profile as an indication of a chronic low grade depletion of potassium associated with pain.
Obviously, if the greyhound has had a previous injury, then this should be brought to the attention of your vet.
Secondly, decide on the appropriate physiotherapy and rest period.
Rest is an important part of the rehab program as it should be long enough for the greyhound to forget about the injury, as well as help reduce the effects of high cortisone hormone levels of the typical chronic pain state.
I often recommend at least 3-4 weeks off with changing daily routines of walking area and strictly no track galloping.
Physiotherapy can include swimming, liniment massage, laser therapy in the case of ligament strain and muscle sheath damage, as well as ultrasound therapy for deep muscle injuries and magnetic field therapy for associated bone and tendon rehab.
It is a good idea to supplement with a 600mg slow release potassium supplement daily for 2-3 weeks.
Thirdly, re-introduce the greyhound to straight line hand slips over 150-200 metres twice a week for 2- 3 weeks before a trial on a circle track, especially if the chronic pain state is centred on the right hind upper hip support driving muscles.
If possible, travel to a track with good banking and a well maintained surface for a trial run to help the greyhound regain confidence when raced in pain free state.
