MUSCLE DAMAGE
By Queensland breeders, Owners and Trainers Association
A greyhound in full flight has only one of its feet on the ground at any one time.
This places considerable pressure on each leg, particularly when driving around a turn. It comes at no surprise therefore, that differently shaped racetracks may cause specific injuries to occur.
Muscle injuries, including ligament and tendon damage, are usually classified as stage 1-2 or 3 injuries, starting with severe strains as stage 1 through to torn or ruptured muscles at stage 3.
Many good books have been written about the injuries sustained by the racing greyhound and their treatments, in particular one written by Dr. James R. Gannon, Dr Linda L. Blythe and Dr. A. Morrie Craig called "Care of the Racing Greyhound"
Anyone wishing to learn more about this subject, or indeed Greyhounds, would do well to purchase the same.
However, I would like to take a step back and look at the reasons for muscle injuries occurring, other than those sustained during specific racetrack accidents.
You can run most greyhound's solo on a safe track, on a safe surface, and after 4 or 5 runs these greyhounds will have sustained some damage to specific muscles.
Quite often there are also, what I can only describe as undesirable changes in the muscle structure.
These changes consist of the top edge of the muscle sheaths separating between various muscles or muscle groups that are normally joined together.
Such as the separation that often occurs between the bottom edge of the GLUTEAL and the top edge of the TENSOR FACIA LATA. This separation if left untreated, will eventually result in a torn groin that splits at the top edge of the PECTINEUS.
The only reason that these changes occur is due to the repetitive strain causing some muscles to tighten into excessive muscle tone.
The muscle still functions and contracts as normal, but is no longer capable of extending to its former length. Creating extra strain to the adjacent muscles or the attachment point of the muscle in question.
As mentioned earlier, muscles don't only contract; they must also be capable of allowing the limb to extend fully. In fact the distance a greyhound is capable of stretching, has a direct bearing on how fast it runs.
And believe you me, the fact that you can stretch the greyhound's legs out for him, has little relationship to the true picture that occurs when he has run for 200 meters or more and some of the muscles have tightened due to the strain.
In golf, the varying distances the ball will travel, depending on how well you follow through with the club is enormous, and yet the ball has already left the club surface.
To a certain extend, the same is true for a greyhound's stride.
The foot has left the ground, but it is the follow through that dictate how far the Greyhounds body travels before the next foot touches the ground.
Treating excessive muscle tone after each and every run will minimize all of the muscle injuries, and maximize the greyhound's speed.
EXCESSIVE MUSCLE TONE
The muscles that are most vulnerable are those muscles that take most of the pressure as the greyhound drives around the turn or accelerates from the boxes.
Left Front Limb
The centre section of the LONG TRICEPS tightens, and when the leg is fully extended this may cause strain and muscle sheath damage to the top attachment, and or the junction between the top and centre sections (egg or pin muscle).
On the forearm the PERFORATUS tightens and this reduction in flexion may cause damage to the tendons that flex the foot and toes.
Right Front Limb
Again the centre section of the LONG TRICEPS becomes too tight.
However, any muscle sheath damage on this leg tends to be more severe due to the fact that on the turn the leg may slide slightly further forward, aggravating the strain.
This tightness in the shoulder will also cause the dog to place the leg in a slightly awkward position on the track, particularly on the turn, causing excessive pressure on the wrist joint.
And if severe enough, this may damage the ACCESSORY CARPAL LIGAMENT, the ANNULAR LIGAMENT, and or the PERFORATUS TENDON.
Left Hind Limb
Because of the galloping style of the modern racing greyhound, this leg is the main driving leg when the dog runs on the straight sections of the track.
The main muscle of concern is the TENSOR FACIA LATA (triangle) this tightens and tends to split away from the GLUTEUS MEDIUS (hip support).
Also of concern is the rear edge of the BICEPS FEMORIS causing damage at its insertion.
However, the muscle that tightens and damages probably the most is the GRACILIS. Excessive muscle tone causes it to pull away from the SEMITENDINOSUS (hamstring) at the lower edge.
Right Hind Limb
This leg takes most of the pressure when driving around the turns, and again the TENSOR FACIA LATA tends to tighten, pulling away from the GLUTEUS MEDIUS.
While the top edge of the GLUTEUS MEDIUS often tightens enough to cause the muscle to almost split in the middle.
Also on this leg the LATERAL VASTUS, which extends the stifle, will tighten sufficiently to cause damage at its uppermost attachment (origin).
As on the left hind leg, the rear edge of the BICEPS FEMORIS also tightens, damaging the lower attachment (insertion)
However, it is the GRACILIS on the right hind leg that generally sustains the most damage, more often than not, damaging the muscle sheath of the SEMITENDINOSUS in the process.
Also on the right hind leg, because of the pressure it takes on the turn, excessive muscle tone may reduce the function of the GASTROCNEMIUS and the PERFORATUS. This lack of elasticity may damage the tendon section of one or both, severely limiting the greyhounds racing career.
The other area of concern is the UPPER TRAPEZIUS (saddle muscle), excessive tension in this muscle will not only result in the front tip damaging, but may also cause the THORACIC section of the spine to lock up, often interfering with the function of the RADIAL NERVE.
All of these injuries reduce the speed and racing life of the greyhound, and all of them originally start with a muscle or section of muscle that tightens too much, can't stretch fully and extend the limb comfortably.
The pressure of acceleration and driving around the turn does the rest.
There is no doubt in my mind that most of the muscle injuries sustained by the racing greyhound would be minimized if the greyhound received regular and thorough massage and physiotherapy, in particularly to those muscles most at risk.
It is a real pity that massage seems to have gone out of vogue, to be replaced by ultrasound and/or laser therapy only when the muscle finally breaks down.
LOCATING EXCESSIVE MUSCLE TONE and INJURY PROBLEMS
Most people when they check a greyhound for injuries simply squeeze the muscle and wait for some type of pain response.
However, this is certainly not the best way to check for injuries, as a severe pain response is often caused by transfer pain from a spinal muscle spasm, or occasionally by the fact that the greyhound is severely stressed and has an excessive build up of toxins in it's system.
There again, if your sense of touch tells you there is a problem with the muscle you are checking, slightly firmer pressure and a pain response will help to differentiate between a past problem or a current injury.
Because much of the muscle damage that occurs to the racing greyhound occurs in the surface of the muscle or muscle sheath, it takes very little pressure to detect.
Everyone can tell the difference between varying surfaces by lightly touching those surfaces, such as the difference between touching a bench top or a sponge, between a rough piece of cloth or a piece of silk.
In fact the harder you press, the less you are likely to feel.
Checking muscle tissue is much like that, with a little practice it is not difficult to feel whether or not a particular area of muscle is harder than the surrounding tissue, or the exact same muscle on the other side if the dog.
Excessive muscle tone does not normally, even with firm pressure, give you a pain response, and yet it is the start of most muscle damage.
When checking each leg for changes in muscle tissue it is important that the leg is supported lightly off the ground and that all of the muscles in the area to be checked are relaxed.
MUSCLE TEXTURE AND LIKELY SIGNIFICANCE
Sound healthy muscle tissue should feel firm, resilient, springy, and with a smooth even texture in the belly of the muscle, firming slightly near attachment points.
The Muscle Feels Ok
Except it is a little harder on one edge. This is the start of a muscle developing excessive muscle tone.
TREATMENT: Massage daily until the hard area softens 50 firm strokes by hand or 20 with a mechanical massager. Apply heat-producing liniment after completion of massage.
The Muscle Feels A Little Harder All Over
This is likely excessive muscle tone, unless of course it feels stringy and rough, in which case the problem is older and there is some scarring. However, the same treatment will benefit both problems.
TREATMENT: Ultrasound twice daily for 2 days, then treat as above, except for the heat producing liniment if the problem is scar tissue.
In that case a product such as LASONIL made by BAYER best replaces the liniment.
The Muscle Feels Hard All Over
With some heat and pain response, but no fluid or swelling. In this situation the problem has gone a little further, and there is likely some strain to the muscle fibres.
TREATMENT: Ultrasound twice daily for 3 days, rest 24 hours, then contract for 1 minute daily for 3 days using a Faradic Current stimulator or the BURST setting on a tens unit.
Apply heat-producing liniment after each contracting session.
The Muscle Feels Hard All Over
Except for a distinctly softer or hollow section at one end or in the belly of the muscle.
In this case there is some muscle fibre disruption and damage within the muscle structure.
If there is fluid or swelling, ice or cold pack twice daily until the swelling is relieved before any other treatment is undertaken.
In a situation such as this a decision needs to be made whether or not the damage is severe enough to require strengthening by injecting a sclerosing agent such as MUSCLE REPAIR or PROMOTE.
Keeping in mind that the resulting scar tissue may reduce muscle flexibility.
TREATMENT: If the damaged area is to be injected this should be done first.
Using a 1 ml syringe with a 29-gauge needle, inject 1/10th of 1 ml at 10 mm centres into the central area of the damage to approximately 10 mm below the skin.
Then inject 1/10th of 1 ml at 10 mm centres keeping approximately 5 mm inside the damaged area, angling the needle to place the injection 5 mm below the skin.
Do NOT inject into the harder area of surrounding muscle tissue.
Rest for 48 hours then use ultrasound treatment, first daily for 2 days, then twice daily for 3 days and again daily for a further 3 days, the first 2 treatments at a maximum setting of 0.8 watts.
After the completion of ultrasound treatments rest a further 48 hours before starting TENS or Faradic Current contracting treatments. After each contracter treatment the area should be massaged and stretched by the appropriate limb movement.
Excessive Separation To Muscle Sheaths
When excessive separation occurs between muscle sheaths, again the decision will need to be made whether or not to strengthen the attachments between the muscles in question.
The problem in this case consists of the fact that this separation would probably not have occurred, if the muscles involved were capable of stretching properly in the first place.
Under these circumstances the treatment would be better limited to ultrasound treatment, massage and physiotherapy only. Simply because the creation of scar tissue may result in one of the muscles tearing eventually.
However, there is sometimes a case for increasing the strength of the muscle sheaths on both sides and at each end of the separation, if it threatens to keep splitting deeper and further.
In this situation inject 2/10th of 1 ml at each end of the split and continue injecting both sides at 10 mm intervals with 1/10th of 1 ml approximately 2 mm inside the muscle sheath, using the appropriate sclerosing agent.
Effectively buttonholing around the area leaving the centre capable of stretching if required.
Following up with ultrasound and physiotherapy is essential.