Trochanteric Bursitis (Whorlbone Lameness) - Equine Veterinary ...

TROCHANTERIC BURSITIS<br />

(WHORLBONE LAMENESS) IN HORSES<br />

James M. Casey, D.V.M, M.S.<br />

<strong>Equine</strong> Sports Medicine, Dentistry, & Surgery<br />

What is <strong>Trochanteric</strong> <strong>Bursitis</strong>?<br />

Office: (301) 725­4371 Cell: (301) 785­5167<br />

Website: www.equinehorsevet.com<br />

TROCHANTERIC BURSITIS<br />

(WHORLBONE LAMENESS)<br />

<strong>Trochanteric</strong> <strong>Bursitis</strong> (whorlbone<br />

lameness) is soreness and lameness<br />

found in the hind end (back legs) of<br />

horses involving a bursa. A bursa is a<br />

saclike cavity filled with a viscous fluid<br />

and situated at places in the tissues at<br />

which friction would otherwise develop.<br />

Inflammation of a bursa is referred to as<br />

<strong>Bursitis</strong>. Thoroughbred race horses,<br />

standardbred race horses, steeplechase<br />

horses, and other sport horses often<br />

exhibit lameness that is localized to<br />

inflammation of the <strong>Trochanteric</strong> Bursa.<br />

This bursa is found in both hind legs, it is<br />

beneath the tendon of the middle gluteal<br />

muscle as it passes over the greater<br />

trochanter of the femur. This area is often<br />

referred to as the whorlbone. There is no whorlbone in horses. This area is<br />

actually the trochanteric bursa.<br />

Why does <strong>Trochanteric</strong> <strong>Bursitis</strong> (<strong>Whorlbone</strong> <strong>Lameness</strong>) Occur?<br />

The inflammation of the bursa is caused by trauma or by a strain on the gluteal<br />

tendon due to a compensating motion of the limb(s) related to both hock and<br />

stifle lameness. Often horses have lameness in either the hock or stifle, at times<br />

both. <strong>Lameness</strong> in the hock and/or stifle alters the normal way a horse moves,<br />

which strains the area of the gluteal tendon and the trochanteric bursa<br />

(whorlbone).<br />

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What are the signs?<br />

Pain may be seen when pressure is applied over the greater trochanter. Also,<br />

when observing how the horse places its hind foot on the ground when jogging.<br />

The inside or medial wall of the hoof comes in contact with the ground before the<br />

outside or lateral wall of the hoof touches the ground. In some cases an<br />

examination of the shoes will note the inside of the hind shoe is worn more than<br />

on the outside of the hind shoe.<br />

Diagnosing?<br />

Treatment of <strong>Trochanteric</strong> <strong>Bursitis</strong> (<strong>Whorlbone</strong> <strong>Lameness</strong>)<br />

The old time remedy was to inject counter irritants<br />

such as iodine into and around the trochanter<br />

bursa. Now, there are more effective treatments<br />

available to replace this procedure. Injection of the<br />

trochanteric bursa with low dose cortical steroids<br />

and hyaluronic acid is a very effective treatment.<br />

This practitioner prefers to use Betamethasone as<br />

the steroid of choice along with a high<br />

molecular weight hyaluronic acid when<br />

injecting the trochanteric bursa. Platelet<br />

Rich Plasma and Stem Cells are also<br />

useful and indicated as an injection<br />

Diagnosis of trochanteric bursitis<br />

(whorlbone lameness) is done by<br />

physical examination and<br />

observation. Diagnostic aids<br />

include Infrared thermography,<br />

which will reveal an increased<br />

thermal gradient (temperature)<br />

directly over the greater trochanter<br />

of the femur. Also, a diagnostic<br />

nerve block using local anesthetic<br />

directly over the bursa will<br />

differentiate this bursitis from other<br />

conditions.<br />

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treatment for trochanteric bursitis (whorlbone lameness). Strict aseptic technique<br />

should always be used when injecting the trochanteric bursa.<br />

Topical application of medical grade DMSO and cortisone (a capsaicin based<br />

product preferred) massaged around the area of the trochanteric bursa will aid in<br />

the reduction of inflammation and pain.<br />

Remember, soreness in the trochanteric bursa (whorlbone) is usually secondary<br />

to lameness in the hocks and stifles. When treating trochanteric bursitis<br />

(whorlbone lameness) the contributing factors, including soreness in the hocks<br />

and/or stifles, need to be addressed.<br />

Managing <strong>Trochanteric</strong> <strong>Bursitis</strong> (<strong>Whorlbone</strong> <strong>Lameness</strong>)<br />

In most cases of trochanteric bursitis, the horse will respond to therapy within a<br />

few weeks. However, when training is resumed, constant physical therapy and<br />

maintenance injections of cortical steroids and hyaluronic acid may be needed.<br />

<strong>Equine</strong> Sports Medicine, Dentistry, & Surgery<br />

James M. Casey, D.V.M, M.S.<br />

<strong>Veterinary</strong> Practitioner and Surgeon<br />

Practicing in the Mid­Atlantic States & Florida<br />

(MD, VA, DE, PA, NJ, GA, KY, FL)<br />

Consults Nationally and Worldwide<br />

Office: 301­725­4371 Cell: 301­785­5167<br />

Email: casey@us.net Website: www.equinehorsevet.com<br />

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