2003 - 16th Annual Bluegrass Laminitis Symposium Notes How To Treat Club Feet And Closely Related Deep Flexor Contraction
Written and presented January 2003 by R.F. (Ric) Redden, DVM
Products for Club Feet Before we begin discussing how to treat any foot problem, we must first take a closer at the details of the respective foot. Many years ago, I found a need to develop a very simple classification system that would allow horseman, veterinarians and farriers to better communicate. Using the graded scale of 1-4 allows everyone involved to be on the same page when discussing a particular case.
Club feet are the result of mechanical imbalances that are most likely attributed to malfunctions within the deep digital flexor muscle belly. The muscle fibers normally receive an electrical stimulus that tells them to contract. This causes the fibers to shorten and subsequently move load. Apparently the imbalance is a problem at the synopsis (nerves/muscle cell unit), which results in the muscle receiving a continuous command to contract. This spastic muscle transfers the constant shortening, or pulling, to the tendon that is firmly attached to the semi-lunar crest along the posterior palmar surface of the coffin bone. Shortening the distance from the origin to the insertion point pulls the coffin bone around its articular axis.
In very soft footing, the laminae and hoof capsules move simultaneously with the flexion of the joint. Anything that changes the free flow action creates a resistance that is directly proportional to the forces at play. Basic ways to increase the counter forces placed on the muscle, tendon, bone, laminae and hoof wall network are:
1. Lower the palmar angle without decreasing the digital breakover. Lowering the heel in an effort to treat the high-heel club significantly increases the tension within the network.
2. Increase the length of digital breakover. Extend the toe using a shoe or composite also increases the forces within the network.
3. Lowering the heel and extending the toe tremendously increase the tension on all structures.
Listed above are three basic treatment plans that are often used in an effort to minimize the high heel/no toe growth syndrome. The counter-pull mechanical plan can be effective on low grade clubs, however it can create a devastating sequence of events for the higher grades. This reinforces the reasons to have a meaningful scale. It allows us to customize each treatment plan to the specific demands of each case.
The grading system for a club foot horse is quite simple, it is broken down into four categories. For individuals who have used it for several years, it can be broken down into twelve categories, grades -1, 1, +1; -2, 2, +2; etc. Note the diagrams below and basic guidelines that will help you quickly develop an eye for all four grades.
The following text corresponds with the images above: Grade 1 -- The hoof angle is 3-5 degrees greater than the opposing foot and a characteristic fullness is present at the coronary band due to the partial luxation of P2 and P3.
Grade 2 -- The hoof angle is 5-8 degrees greater than the opposing foot with growth rings wider at the toe. The heel will not touch the ground when trimmed to normal length.
Grade 3 -- The anterior wall is dished and growth rings at the heel are twice as wide as the toe. Radiographically, P3 exhibits demineralization and lipping along the apex.
Grade 4 -- The anterior hoof wall is heavily dished with an angle of 80 degrees or more. The coronary band is as high at the heel as at the toe while the sole is below the ground surface of the wall. Radiographically, P3 is rounded due to extensive demineralization, and rotation may be present.
When discussing how and when to treat club feet in horses, we must also look at the age and intended use of the animal. Treatments tailored for the unique characteristics and demands of each foot often reap more successful outcomes.
The club foot syndrome can be found in foals one month of age. The lower grades, 1 and 2, are the most common. The majority of cases reach four to five months of age before noticeable differences are detected. Newborn foals that have significant deep flexor contraction are often up on their toes or even knuckled over with the more severe contraction.
Most cases respond in a favorable fashion using a variety of treatment methods; tetracycline, toe extensions (taped or glued on), splints, cast, snap on fiberglass splints, air splints and stall confinement can be used very successfully to treat the foal with a contracted tendon. Keep a record of foals with contracted tendons and you will find a large majority develop a club foot with a grade of 2 or higher by the time they are five months of age.
Treating early stage club syndrome increases the odds of preserving bone integrity and the health of the soft tissue growth centers. Therefore, it is very important that all responsible parties develop an eye for the early changes that clearly describe a grade 1 club. The first noticeable difference is the pastern alignment. It is pushed forward and will appear in the same linear plane as the face of the hoof capsule.
Stand back ten feet and look at the negative space that borders the face of the hoof and pastern. The normal foot will have a pastern that is set back slightly and still be parallel to the anterior face of the hoof. The toe angle will be 5 degrees steeper than the opposite. The angle depends on the breed, age and the unique characteristics of the individual.
I disagree with much of today's literature that describes feet on young horses as having 60 degree hoof angles. It is obvious to me that individuals who subscribe to that opinion have never actually measured the toe angle on many foals. It is rare to find a foal with a hoof angle less than 63-65 degrees, regardless of the breed. This angle doesn't start dropping for several months unless aggressive trimming techniques are used to remove the strong heel that is found on most foals.
Looking closely at the sole surface of a club foot, the bars are beginning to turn inward at the heel and many times touch the frog. Compared to the opposite heel, there are stark differences in angles of the quarters. The heel tubules are slightly tighter with as much as 5-10 degrees difference. Using close up photography, with the projection angle perpendicular to the surface of the foot, you can train your eye to notice the subtle details.
Treating the Club Foot, Grade 1 I like to push the heel back to solid, strong heel starting at the center of the frog area. I then rocker the toe forward from the same point leaving the center of the foot as a noticeable pivot point. Leave the frog and sole and put a smooth, but non-invasive, radius on the ground surface horn. This method promotes the flow of nutrients to the sole, which accelerates sole proliferation. This, in turn, protects the very soft and vulnerable palmar surface at the apex.
Enhancing sole growth also stimulates anterior horn growth. This effect is the direct result of significantly reducing the tension on the deep digital flexor tendon by pushing capsular breakover to the middle of the foot. The tendon is not opposed by forces at the toe, therefore a lifting effect occurs within the capsule. This phenomenon can be clearly demonstrated with venograms. Re-examine the foot in ten days, if the heel and toe growth rate appear to be equal stay with this very simple, but yet effective, method.
Trim the foot every two weeks to maintain the mechanical advantage necessary to offer equal toe and heel growth. Some grade 1 feet will remain as such for the duration of the horse's life without any treatment whatsoever. Others will proceed up the ladder to the higher grades; some very rapidly, others taking many months to reach the higher grades. At the onset, it is difficult to know which one will have a stronger tendency to continue contracting. Treating all of them very early certainly sorts this out very quickly.
For many years, traditional methods have been prescribed for club feet as a whole (no grades considered). These methods focus on making the f