Newsletter

June 2017

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"The greatness of a nation and its moral progress can be judged by the way its animals are treated." ― Mahatma Gandhi

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NEWSFLASH: Unfortunately the CSW 2 that was supposed to be held in Cape Town in June had to be cancelled due to lack of interest.                   

 We had to reschedule another CSW 2 in Johannesburg  from 17 to 20 August 2017 

 So, an exciting course with very interesting lectures awaits us at Grey Hare Farm. Don't miss out!

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Rehabilitation for Stifle Dysfunction

                                                                                            By Amie Stewart

Several of our equine patients may suffer from stifle dysfunction, in which, “Upward Fixation of the Patella” is one of the main causes. It may also be referred to as “Delayed Patella Release” or a “Locking Stifle.”A locked stifle usually occurs due to extended periods of immobility, disease, surgery, or traumatic injury.

In order to stand for extended  periods while sleeping or to rest the opposite hind leg,without expending excessive energy, horses must naturally be able to lock their stifles and engage their reciprocal apparatus when their leg is in extension. The medial patellar ligament hooks over the medial trochlear ridge of the femur in order to achieve this “lock”, which stabilizes the extended leg. When the horse wants to flex the hind leg, the medial patella ligament unlocks and the patella is free to move up and down within the trochlea grove.

Intermittent upward fixation of the patella,occurs when the horse tries to flex the hind-limb, but the medial patellar ligament remains hooked over the medial trochlear ridge of the femurand locks the reciprocal apparatus with the limb in extension. The horse will present with the affected hind-limb fixed in extension as well as with a flexed fetlock. They will be unable to flex the hock and will drag or swing the leg, hop or kick out until they are able to release the fixation with a sudden or jerky movement. 

Milder versions involve a “stickiness” of the stifle as the horse moves between upward and downward transitions. This is seen as jerky movement around the stifle area and the horse’s leg may often collapse, stumble or “trip” underneath the rider or appear to be circumducting instead of flexing during hind-limb protraction. Owners may report clumsiness as well as audible clicking and popping noises during work. The horse may develop a chronic irritation of this joint and become reluctant to walk up or down hills, to work in circles, on thick surfaces or move between transitions smoothly.

 

In an acute setting where a horse’s stifle locks and doesn’t spontaneously release, it is advised to rein the horse back while pushing the patella medially and distally in order to unlock it. If this fails, one can also try to flex the leg forward.

 

Specific causes include poor muscle condition, muscleasymmetry, inactivity, very upright hind-limb conformation as well as direct trauma to the stifle.

 

Treatment of “upward fixation of the patella” should be compared to treatment given to a human patient with anterior patella-femoral knee pain. The program is time intensive for both the owner and the patient and requires maintenance in order to prevent re-occurrence, once symptom free.

 

Assess:

• Determine if the problem is A. acute or chronic and B. mild, moderate or severe in nature. This will guide your progression of exercises and healing time frame 

• Determine which specific muscles are atrophied and need strengthening. The muscles that are normally affected include the core,quadriceps, gluteal and hamstring muscle groups

• Determine if the horse has a related proprioception deficit

• Assess trot up, rein back, walking up and down a hill, turning on hind quarters as well as walking/trotting in a circle

 

Educate:

• Educate the rider and owner on the importance of regular, consistent work. For affected horses, a minimum of 6-7 days of varied work per week, is recommended

• Stress the importance of giving the horse ample paddock time and being in a paddock where they are encouraged to walk and play with other horses. 24-hour paddock turn out is ideal

• Have grass placed in piles at different corners of the paddock to encourage movement

• The horse will naturally opt to rest the painful leg and this should be discouraged as it can fuel the non-use cycle and lead to further weakness and pain

• If the horse is in considerable pain, contact the owner’s vet for adjunctive pain medication

 

Treatment:

• Soft tissue treatment: gluts, hamstrings, quads and medial patella femoral ligament

• Joint mobilization: repeated end of range hip, hock and stifle flexion

• Muscle stimulation eg. Faradic

• TENS for pain modulation

• Stretching: hind-limb protraction, adduction, retraction

 

Progressive Strengthening Program:

Adjust according toyour assessment of the stifle dysfunction severity

 

Week1:

• Isometricseg. hind quarter weight shift exercises

• Balance exerciseseg. standing on 1 hind leg (progress from 5-30seconds).Anterior to posterior or lateral weight shift can be added to advance this exercise

• In-hand walking program: start on flat, hard surfaces and encourage an active walk where the horse tracks up correctly. Progress the walking time from 10-30min

 

Week 2:

• Hill work: start with small gentle hill work. Increase hill size, duration and repetition slowly over 3 weeks.

• Progress the walking surface from flat to uneven

• Start walking over evenly spaced, flat ground poles. 

 

Week 3:

• Start ridden walking (must be forward and active) and progress through the exercises in week 2 while ridding.

• Start in hand rein back work (progress from 3 to 8 steps slowly)

• Progress to thicker walking surfaces

Week 4:

• Start walk to trot and trot to walk transitions and encourage a forward active trot in-between transitions

• Start 10min of theraband work per day to activate and engage the affected hind quarter muscles

• Advance pole work: lengthen and shorten the distance between poles

 

Week 5 onwards:

• Advance pole work: start walking over raisedalternating poles and poles on a circle

• Progress theraband work by 2min every 3rd day

• Advance hill work: increase reps, steepness and duration

• Start big circle work

 

Week 6 -8

• Start canter work and canter transitions (light seat if need be) and remember to encourage forwardness

• Advance pole work: start basic trotting pole and canter pole exercises. Only start raised alternating trotting poles after 8 weeks.

• Start turn on the hind quarter and turn on the forehand exercises

• Begin ridden rein-back work (progress from 3-6 steps)

• Progress theraband work toa total of 30min (only flatwork)

• Progress hill work: start basic pole work on hills

• Circle work: make progressively smaller

• Start long line work

• Swimming if and where possible

 

If the patient is sound and pain free after week 8, return to a normal, but progressive trainingprogram, introducing elements of the patient’s specific “return to sport” requirements gradually.

It is imperative to remind owners that the hill, theraband, pole and specific flat work exercises mentioned above must be performed at least 2x week to maintain the strength gained and to prevent re-occurrence. 

Examples of Pole Exercises

References:

• Boswell, J. Intermittent Upward Fixation of the Patella and Delayed Patella Release in Horses. Merck VeterinaryManual. Available at: http://www.merckvetmanual.com/musculoskeletal-system/lameness-in-horses/intermittent-upward-fixation-of-the-patella-and-delayed-patella-release-in-horses[19 June 2017]

• Dyson, K. (2013) Dealing with Locked Stifles. Farmer’s Weekly Available at: http://www.farmersweekly.co.za/animals/horses/dealing-with-locked-stifles/[19 June 2017]

• Gronberg, P. (2002)ABC of the Horse Anatomy Biomechanics and Conditioning. Finland: Otava Book Printing Ltd, 52,54,167.

• Reinhold, S. (2016) Locking Stifles in Horses. Natural Animal Health Support.Available at:http://naturalanimalhealthsupport.co.nz/locking-stifles-in-horses/[19 June 2017]

• Reinhold, S. Understanding Locking Stifles. Holistic Horse. Available at: http://holistichorse.com/health-care/understanding-locking-stifles-3/[19 June 2017]

• Stashak, T. (2006)Practical Guide to Lameness in Horses. Iowa: Blackwell Publishing Professional, 341-343.

• West, C. (2012) Physical Therapy for Stifle Problems in Horses (AAEP 2011). The Horse. Available at: http://www.thehorse.com/articles/28662/physical-therapy-for-stifle-problems-in-horses-aaep-2011[19 June 2017]

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Laugh A Little!

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Hope to see you all at the CSW 2 at Grey Hare Farm Jhb

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