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The
first and most important reason to provide for a safe running surface is
to protect the Greyhound from race related injuries, but the surface also
influences many other aspects of the racing industry. Greyhound racing
injuries are a primary concern to the Greyhound industry for both humane
reasons and economic reasons. With today's general concern for the
humane treatment of animals, it is important that the public be assured
that everything possible is being done to minimize the incidence of injury.
Also, with the investment that is involved in preparing a Greyhound for
a racing career there is a definite economic loss when a racing injury
occurs. When a greyhound is injured there is an initial cost of treatment
and rehabilitation, which is on top of the fact that when a Greyhound is
injured, he or she can not produce an income due to the rehabilitation
time.
A proper racing surface also
provides an even competitive field and a consistent racing environment.
This assures the betting public that the race outcomes are based upon the
running skills of the Greyhound. A consistent track maintenance
program provides for healthy handicapping. The end result is a satisfied
betting public. The racetrack benefits from the profit derived from
the positive public experience. Therefore, prevention of racing injuries
is beneficial not only to the greyhound itself, but also to the owners,
trainers, track regulators, and racetrack owners.
It is the role of the Sports
Medicine Veterinarian to find ways to minimize potential injuries of their
patients. There are two major influences upon injuries of the racing
greyhound, the trainer and the racetrack. The trainer maintains and
monitors the health of the greyhound. The racetrack is where the
Greyhounds perform their activity. A safe racing environment is created
through proper track design, correct surface content ratio, and proper
track maintenance.
Factors that Influence Greyhound Performance
& Injury
One way to help prevent
racing injuries is to provide a safe and consistent racing surface.
A knowledge of injury mechanisms, or factors, that relate to running, aids
in the prevention of injuries. The factors that affect performance,
and subsequently the risk of injury of the Greyhound, can be divided into
internal and external factors (Table 1). The internal factors that
affect the Greyhound are their anatomy, physiology, and psychology.
These factors are influenced by genetics, the breeder, and the trainer.
The genetic factors predetermine a Greyhounds performance potential and
potential to injury. The breeder influences the maturation of the
Greyhound. The trainer manages the racing career.
The external factors that
affect the Greyhound are the environment, dog interaction, the lure, track
design, and the racing surface. Environmental factors can include
rain, humidity, altitude, and others. Dog interaction can come in
the first turn, Ginny Pit, or the kennel. The lure type and distance
from the dog can affect how the Greyhound runs. Track design issues
include the length of the straightaway, and the radius and bank of the
turn. The racing surface is influenced by the contents that compose
its makeup and its depth. The key influence on racing surface is
track maintenance.
Table 1. Factors related
to the injury and performance of the racing Greyhound
| Internal Factors |
External Factors |
-
Anatomical
-
Physiological
-
Psychological
|
-
Environment
-
Dog interaction
-
Lure
-
Track Design
-
Racing Surface
|
Some factors we can control
and others we cannot. Weather is a major factor and one that we cannot
control. The racetrack design and surface content should be determined
by the local weather conditions, i.e. humidity, precipitation, temperature,
and the other climatic factors. The weather will also be an important
factor in creating the maintenance program.
There is minimal control
over dog interaction. During the race the Greyhounds can come into
contact with each other. It is important that they are able to navigate
themselves around the track so that they are less likely to bump into each
other or get out of balance. Out of balance or out of control running
places abnormal forces upon the musculoskeletal structure. The forces
will predispose the Greyhound to injury. A loose track does not provide
traction, which lessons the Greyhound's ability to control itself.
The problems related to dog interaction are reduced when the Greyhound
is able to steer itself while running.
The racetrack operator has
control over the other external factors. They are responsible for
designing the track and selecting the surface content. The lure operator
controls how the lure is run and management is in charge of track maintenance.
Racetrack Analysis
Two ways to assess the racing
surface are by using injury reports or by analyzing the surface.
Injury reports can be used to determine the status of the racing surface.
If there is a rise in injuries the racing surface should be considered
as a possible cause. Certain injuries are related to various surface
problems. This is a controversial way to assess the racing surface
because changes to the track occur after the injuries have occurred.
The surface itself can be analyzed for changes or problems. The content
can be analyzed or base measurements can be determined. This method
is better in preventing injuries.
Racetrack Analysis by
Injury Reports
No racing related injuries
should be the goal of any racing facility. The track management
program should be designed to meet this goal. Once this goal is accepted,
it should be recognized that injuries can occur in any sporting or working
environment. In a survey reported by Bloomberg and Dugger, there
were 761 injuries reported for a total of 47,323 races ran at sixteen racetracks
between the years of 1984-1990. Eight Greyhounds run in a race, so
the total number of greyhounds competing one time or more included in this
survey were 378,584. This means that the injury ratio is 0.2%.
This number of injuries is
miniscule, when compared to figures from the field of human sports medicine.
Sports Injuries Online, a website developed to provide sports medicine
information, reports that sports injuries are the leading cause of unintentional
injury in children and youth and peak at 42% annually for people aged 15
to 24. They also report that sport Injuries represent a significant
public health concern accounting for 23% of all traumas. When a comparison
is made between human athletes and canine athletes, it shows that Greyhound
racing is a very safe sport. This should not change the goals of
management, they should still strive for zero racing-related injuries.
Each racing facility regulatory
veterinarian should keep a record of racing injuries. If a sudden
increase in numbers occur, the racing surface should be evaluated for surface
alterations. There can be seasonal variation in injury numbers, but
these will be documented by the injury records. Certain track conditions
will produce injuries related to that condition. Table 2 describes
the types of injuries related to certain track conditions.
Table 2. Injury types
seen with certain track conditions
| Track Condition |
Hard Track |
Soft Track |
Inconsistent Track |
| Related Injuries |
|
-
Shoulder
-
Muscle
-
Traumatic Injuries
|
-
Toe, M/C, Carpal
-
Shoulder, Muscle
-
Balance Related injuries
-
More Severe Traumatic injuries
|
Assessing the racing surface
using injury reports is one way to assess racetrack status. It requires
little effort by the individuals involved and requires minimal knowledge
of the racetrack mechanics. Its drawback is that the injuries have
occurred before any evaluation is possible.
Racetrack Analysis by Surface
Evaluation
Once the basic information is
accumulated to understand the normal paw-to-surface interaction the racing
surface can be analyzed periodically for detrimental surface changes.
That way surface problems can be detected before the injuries occur.
The information required to have a basic knowledge of the foot-surface
relationship includes content materials and ratios, base depths, force
absorption, and surface traction.
Impact Information
The Greyhound racing gait
is a double-suspension rotary gallop. In this gait the lead front
led contacts the surface where it supports the weight of the body and the
forces related to their racing propulsion. The lead leg receives
2.26 time’s the body weight of the Greyhound. For example a 70 pound
Greyhound will impact the surface with 158 pounds of force. Once
the paw touches the track the racing surface must allow for the paw to
grip the track. The proper coefficient of friction needed for a racing
surface to provide grip is 4.047.
This coefficient value can
be used to determine if the track is hard or soft. Anything less
than 4.047 will create a slippery interaction. Anything greater than
4.047 creates a hard track. These values have been determined by
using the Greyhound racing kinematic information. More information
needs to be accumulated before these values can be applied to track evaluation.
There could be an acceptable range for the coefficient once further research
is performed.
Surface Content
The components of the racing
surface in the United States are sand, silt, clay & water (Figure 1).
The particles are defined by size: Clay (< 0.002 mm); Silt (0.002 -
0.05 mm); and Sand (0.05 - 2.0 mm). The ratio of these components
will determine how that track absorbs the paw. The proper ratio will provide
a safe racing surface (a). A wet track or one with too much water
(b) will not provide proper traction and impact absorption. A dry
track that is composed of too much sand will produce a loose track (c).
A dry track that is low on sand content will produce a hard track.
Samples are taken from the track to assess the content ratio. These
samples can be usually sent to any local academic institution that can
run a soil analysis. The analysis will provide a content ratio of
the surface components.
Figure 1. An example of
the various content issues affecting the racing surface. (a) a normal ratio,
(b) a watery track, (c) a dry high sand track, (d) a dry low sand track
Surface Content Analysis
Samples are taken from the
track to assess the content ratio. These samples can be usually sent
to any local academic institution that can run a soil analysis. The
analysis will provide a breakdown of the component percentages as seen
in Figure 2. It will also provide a water percentage. The samples
should be taken from at least 8 places around the track. They should
be taken from the in front of the starting box, from the mid-track of the
front stretch, from the rail entering the first turn, from the mid-track
entering the first turn, from the rail at the middle of the first turn,
from the mid-track of the middle of the first turn, from the back stretch,
from the rail of the second turn just below the 3/8's box, and from the
middle of the second turn. In the front stretch, in the rail of the
middle of the first turn, in the mid-track of the first turn, in the back
stretch and in the second turn the samples should be taken from two depths.
One sample should be taken of the top 3 inches and another one of the lower
3 inches. Over time the surface components will shift as a result
of weather conditions. The smaller particles will gravitate to the lower
part of the base. In the turns the larger particles will slide down
the bank towards the rail. Getting samples from two depths determines
composition ratio for the depth of the surface. A "Sandy Loam" or
"Loamy Sand" type of make up is the optimum content make up for the Greyhound
racing surface.
Figure 2. A particle triangle.
In the USA the Greyhound racing surfaces are made up of a mixture of sand,
silt and clay. The ratio of these particles defines the nature of
the surface.
Track Layers
The racing surface is divided
into two theoretical layers (Figure 3). The absorptive layer is the
surface depth that the paw goes through until it grips the track.
The traction layer is the level where the paw grasps the track. These
layers are controlled by the content make-up and track maintenance.
Figure 3. The racing surface
is composed of two layers. The absorptive layer is the part of the
surface where the paw enters. The absorptive layer is the depth where
the paw stops and grips the track.
The layers of absorption
and traction should be even for the length and width of the track
(Figure 4). The depth of the absorptive is called the base depth.
This depth should be the same in the straightaways and the turns.
An even depth is important for safe controlled running. It gives
the Greyhound good footing and provides for safe and consistent racing.
Figure 4. The base
depth should be even for the length of the straightaways and turns.
It should also be even for the width of the track. This provides
for equal footing for all of the Greyhounds in a race.
Track Layer Analysis
A base map can be used to
evaluate the layers of the surface. The base can be measured by inserting
a ruler into the surface (Figure 5). It is important to insert it
with the same amount of force for each measurement or you can get an incorrect
reading. It is also a good idea to do this after the track has been
packed down. A good time is after the last race of the card.
A base map is created by taking base measurements at important locations
around the track. Measurements are taken at three sites for the width
of the track. This is because Greyhounds run in basically three paths
around the track. There are rail runners, mid-track runners and wide
runners. Measuring the depth of these racing paths determines if
there is any variation in the base of the three paths. Therefore there
are three measurements for each track location.
Figure 5. A ruler is inserted
into the track to determine the base depth. It is important to use
the same force for every measurement taken for proper analysis.
There are nineteen locations
around the track that should be measured (Figure 6). One location
is at the starting box, three locations along the front stretch (FS2 -
FS4), seven locations around the first turn (FT6 - FT12), three locations
on the back stretch (BS13 - BS15), and four locations around the last turn
(LT16 - LT19). The reason for so many locations around the first
turn is that many different forces occur at this location. At the
beginning of the race the Greyhounds enter the first turn at the greatest
speed during their race. This creates a lot of outward push on the
racing surface. Later at the end of the race this is where the Greyhounds
slow up to stop at the end of the race. They dig in and push the
surface forward. Another reason is that usually the first turn is
banked. Over a period of time the surface content will be altered
because of weather and track maintenance. The measurements should
be consistent for the length and width of the track (Figure 7).
Figure 6. The base depth
should be measured at nineteen locations around the track. Three
measurements are taken at each location to assess the three running paths
of the Greyhounds.
Figure 7. The measurements
should be consistent for the length and width of the track. The paths
are indicated as S1- rail; S2 - midtrack; S3 - wide. The values are
listed in inches.
Banking of the First Turn
The banking should be evaluated
at the first turn. The bank should be measured at the mid-turn location.
It should be evaluated using the base measurements not the surface top.
Insert a ruler into the surface at the rail path. Insert a second
ruler in the midtrack path. Measure the deepest of the two measurements.
Run a string from that measurement to that same measurment on the other
ruler. Use a level to determine the horizontal line. The degree
of banking is measured between the horizontal line and the line of the
string. This is repeated by measuring the bank from the midtrack
path to the wide path. The bank of the turn should measured in two
parts because it is common for a crown to occur in the middle of the track
at the first turn. Measuring the base depth instead of the surface
will expose this problem.
Altered Track Conditions
Weather and track design
can cause changes in the racing surface content ratios over time (Figure
8). The particles will shift because of gravity or they are redistributed
because of paw-surface interaction. They can also be altered because
of raking or track work-up. Weather, track maintenance, and normal
wear & tear will also affect the base depths. These changes create
an uneven racing surface.
Figure 8. A surface that
has variable content materials. (a) watery loose track (b) proper
content ratio (c) dry low-sand track (d) dry high-sand track
Figure 9. A surface that has
an uneven base. The base can be uneven through the length of the
track or it can be uneven across its width. Both can be a cause
of racing injuries.
A base depth map will show
the track's discrepancies. The example shown in figure 10 shows base
depths that very from 0.2 inches to 1.4 inches around the track.
The track is especially deep at the first turn 1.4 inches at the rail locations
of FT8, FT 11 and FT12. FT8 is at a location where the Greyhounds
are acting upon the surface to make their turn. FT11 and FT12 are
just after the brake area. The racing surface in these areas are
deep or soft and provide less traction than the harder areas. This
would predispose the Greyhounds to uncontrolled running which is one of
the causes of racing injuries. This example also demonstrates that
there is a difference in the running paths. Coming out of the first
turn, the greyhounds running on the midtrack or wide path will have a much
harder surface than the greyhounds running on the rail path.
Figure 10. An example
of an inconsistent racing surface. The paths are indicated as S1-
rail; S2 - midtrack; S3 - wide. The values are listed in inches.
Surface Analysis and Maintenance
It is important to know the
base depth of the track because it affects how the track will be managed.
If the track has an uneven base the normal maintenance will be inappropriate
(Figure 11). If the normal maintenance is performed without the base
information the problems are not repaired. The cut may not be deep
enough to level the base of the track.
A. |
B. |
Figure 11. (A) The normal
maintenance procedure involves packing the track and then cutting it before
the next race card. (B) If the base is not known, the normal maintenance
protocol will not address the surface problems.
Correcting the Problem
The track surface evaluation
will determine how to manage the racing surface. If the surface material
content has changed this can be determined by a surface content analysis.
It is possible that the track can be rototilled to remix the surface content
or mix in needed material. A base map will determine if the base
of the track is uneven. If the base is uneven the track should be
cut according to the depth determined by the base map and then repacked
and cut as seen in Figure 12.
Figure 12. The cutting
blade is set at a depth that levels the track base. The track is
then packed evenly and then cut in preparation for racing.
Summary
It should be our goal to provide
a safe running surface for the Greyhounds. An even and consistent
racing surface will minimize racing-related injuries and optimize the ability
of these athletes. Racetrack maintenance is the most important factor
in maintaining the proper surface. The proper management program
requires a procedure to determine the track status. Once the track
status is defined, the proper corrections can be made. Research is
currently being performed to define an impact model for the racing Greyhound.
Once this model is finished it can be used to monitor the racing surface.
It can be set upon the surface to measure how the surface receives the
impact forces. If the surface is too soft or too hard the instrument
will indicate those locations to the track manager. This information
can then be used to develp the proper track mangement program. It
will also allow test to be perfromed in the laboratory to determine which
surface materials should be used to produce the optimal racing surface.
Until this model is available, the evaluation procedures outlined in this
article should provide a viable way the racetrack managers and the regulatory
personnel to assess the racing surface.
References
-
Bloomberg, M. S. and W. W. Dugger,
Greyhound Racing Injuries: Racetrack Injury Survey. Canine Sports Medicine
and Surgery, pp 412-415, Philadelphia WB Saunders Company, 1998
-
Gillette, R. L. Track Surface
Influences on the Racing Greyhound. Greyhound Review, April, 1992.
-
Gillette, R. L. and C. J. Zebas.
A Kinematic and Kinetic Analysis of the Greyhound Racing Pattern. Technical
report presented to the Kansas Racing Commission August 8, 1991.
-
Sports Injuries Online, www.sports-injuries.com
Dr. Willem Meeuwisse and Terry Kane, 2001
-
Zebas, C. J., Gillette, R. L.,
Hailey, R. L., Schoeberl, T., Kratzer, G., & Joseph, Y (1991). Kinematic
descriptors of the running gait in the greyhound athlete. In R. N. Marshall,
G. A. Wood, B. C. Elliott, T. R. Ackland, & P. J. McNair (Eds.), XIIIth
International Conference on Biomechanics (pp 469-470). Perth, Australia:
University of Western Australia.
-
Zebas, C. J., R. L. Gillette,
R. L. Hailey, Y. Joseph, & T. Schoeberl (1991). Selected kinematic
differences in the running gait of the greyhound athlete during the beginning
and end of the race. In C. L. Tant, P. E. Patterson, & S. L. York (Eds.),
Biomechanics in Sport IX (pp 81-84). Ames, IA: Iowa State University.
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