In this article, we will discuss rehabilitation principles for common muscle problems, which generally involve 80% of the common race day injuries sustained by racing greyhounds.
Muscle Injuries
Muscles can become damaged as a result of raceday falls, over-exertion or strain due to sudden overload.  The build up of acid metabolites during galloping which results in ‘acidosis’ in an unfit greyhound can also cause pain and damage to muscle cells.  Muscles are very vascular structures and the number of blood vessels feeding a muscle increases in response to exercise.
This helps transport more oxygen into the muscle to improve aerobic fitness and oxygen uptake.
Therefore, any fall or traumatic injury directly to a muscle can result in bruising and bleeding under the skin, or more deeply within the muscle itself.
The high blood pressure generated during a race can rupture more vessels.
Often a pocket of blood or a ‘haemotoma’ forms within the bruised area, or where the muscle fibres themselves pull apart due to overload strain.
Certain muscles, such as the long head of the triceps (or ‘egg, pin or monkey’) muscle behind the shoulder blade, and the gracilis muscle in the groin, pull away or become ‘dropped’ from their attachments to bone, with bleeding, collection of blood and swelling.
In fact, the gracilis muscle, often referred to as the ‘back or groin’ muscle, appears to have a ‘use by’ date at 3-3 _ years of age, and the incidence of ‘dropped’ gracilis muscles increases dramatically in greyhounds still racing after this age.

First Aid
If you suspect muscle bruising as a result of a fall or collision, or a tear because of a sudden loss of speed not related to interference or cramping, then applying an ice pack as soon as possible to the skin over the area will limit bleeding and formation of a haematoma.
A ice pack can be improvised by the use of a packet of frozen peas or corn, a handful of ice chips in a plastic bag from the track canteen, an ice-cold can of drink, or a specially designed gel cold pack can be used.
The ice pack should be held in place with firm pressure for 2-3 minutes at a time to ensure the cold constricts the bleeding vessels, controls pain and swelling and confines the injury.  If a greyhound is hot after a run, the ice pack may be left in place for 4-5 minutes on the site of a muscle injury without risk of cold ‘burns’ to the skin.
A pressure bandage, made of elastic tape, is useful to hold the pack in place and exert continuous pressure to reduce bleeding.
Pulsed Magnetic field therapy set on a low frequency is often used to constrict the bleeding vessels within muscles, and a similar frequency of application for 15-20 minutes at a time may be of benefit.
Cold Therapy first 24-36 Hours
For most muscle injuries that include swelling and a ‘squelchy’ soft consistency due to bleeding, repeat applications 3-4 times a day for the first 24-36 hours, combined with rest will help to control the swelling and confine the bleeding.
In more serious injuries, application of an ice pack 2-3 times daily until 48 hours after injury is recommended before applying any form of massage, heat therapy or ultrasonic therapy that could interrupt and traumatise the damaged vessels, so that they start to seep blood again.
Your vet will give you specific advice on each type of muscle injury relative to the muscle and its location.
Even if you do not notice the swelling and pain associated with a mild muscle injury until the morning after a trial or race, apply an ice pack as soon as possible to reduce swelling, fluid build-up and discomfort.
Obviously with this type of injury, the greyhound has to be confined to a kennel, and only waked out on the lead to empty out 3-4 times a day, usually just before applying the ice therapy.

Heat Therapy After 48 Hours
Healing is promoted by an increase in the blood supply to deliver more nutrients to the tissue.  This encourages an optimum rate of cell division to repair the damaged tissue.  Once the damaged blood vessels have healed over, often the removal of the bruising or haematoma residue can be assisted by gentle massage to disperse the fluid (serum).
Other forms of physiotherapy, such as ultrasonic therapy should be withheld until he 4-5 days of a severe bruising or haematoma, as the heating and vibration type effect may damage healing blood vessels and cause renewed bleeding and seeping of blood into the area.

Massage
Gentle rolling massage with the fingers applied over an injury site is a simple and effective initial form of therapy.
To be effective, massage does not have to exert excess pressure – a gentle ‘soft’ massage is all that is required, although deeper injuries may benefit from a “kneading” type of massage technique.
Massage provides a “feel” for the injury, but it is time consuming.  A warming oil-based liniment, such as 10mL (1-tablespoon) Iodised Oil helps lubricate the skin during massage and retains warmth as the blood flow increases and brings core body heat into the injury site.
A liniment such as Iodised Oil, for instance, contains a small amount of iodine, which controls any skin infection and creates a counter irritant warming effect on the skin.
It also contains “Oil of Wintergreen” (methyl salicylate) to soothe discomfort and reduce swelling.
However, applying more than one tablespoon per day leading up to a race may allow enough salicylate to be absorbed to pass out in a detectable amount.
Obviously, for massage to an injury, swabbing is not a problem.
It is best to gently massage for a 2-3 minutes at a time, depending on the type, site and extent of the injury and repeat 3 or more times daily, rather than massage for extended periods.
It is also not recommended to massage over a site of possible infection within an injury, as it can dispense the infection into the surrounding tissue.
It is also important to cease massage if irritation develops on the skin or the greyhound resents the procedure.

Magnetic Field Therapy (MFT)
Many trainers have a MFT unit, such as a Portamag, and use it as part of their muscle toning and pre race warming-up program, for after race cooling down as well as to reduce stiffness and soreness after training and trialling.
Although direct scientific evidence has not been able to confirm that MFT increases blood flow in tissues as a basis for the response obtained, there is evidence that MFT can hasten healing of bone fractures.
Most MFT advocates recommend pulsed electromagnet MFT therapy rather than static magnetic fields in a bandage or blanket type application.
Normally, 15-20 minutes twice daily is recommended for most forms of muscle injury, although deeper injuries may be given therapy at a higher frequency and for a longer duration.  In most cases, minor injuries are given 3-5 days therapy, with more severe or chronic injuries being given therapy over a 10-14 day period.

Laser
In many cases, lasers are not well suited to muscle injuries and laser therapy is probably limited to tears at the ligamentous insertions rather than muscle body injuries.  Again various frequencies can be used for specific applications.

Ultrasound
In the view of many trainers and veterinarians, ultrasound still remains the best overall form of physiotherapy for a range of muscle injuries, although severe injuries cannot be safely treated within the first 4-5 days as further tissue damage may occur.
In most cases, it is best to allow your veterinary surgeon, or an experienced greyhound physiotherapist to apply and manage the use of ultrasound therapy for muscle injuries.
Usually a power setting of 0.5-1.00 watts per square centimetre applied by moving the ultrasound head over the injury for 3-4 minutes twice daily is a starting point for most injuries.
Applying Iodised Oil as a coupling medium can reduce therapy time to half, but this must only be used by a qualified physiotherapist.
Muscle Contractors
A Faradic unit, or a muscle stimulator or contractor that uses a small electric current to stimulate a controlled muscle contraction, can be a useful adjunct to other therapies.
The muscle contractor is used to strengthen muscles that have lost tone following a rest up and therapy session lasting more than 7-10 days.
Again, the muscle contractor is best used by a qualified and experienced person, as the degree of response has to be carefully monitored to avoid excessive contraction and further muscle damage.