Shai Halimaar

Case #156122

Shai Halimaar• 7 year old Arabian gelding

– Historically (06/09), Diagnosed and treated for EPM– First presented on 6/2/10

• Owner complaint: Right forelimb lameness– March 9th, 2010: first noticed – March 10th: Examined and referred to Dr. Meyer– March 16th: Diagnosed with a suspensory injury

• Stall rest and Phenylbutazone until 3/22• Acupuncture and Chiropractic work

– March 23rd: After having been placed out on pasture, again lame RF• Rest, ride (4/11, 4/30, 5/4), lame… then repeat, until…

Presentation at NCSU-VTH

• Physical exam within normal limits• Lameness exam– Mild 3/5 RF in a straight line on a hard surface, worse under

saddle• Flexion tests were negative, both front limbs

– Circling on the left rein on a soft surface• Produced a left front lameness

– Circling on the right rein on a soft surface• Accentuated a right front lameness

– PD of RF = LF lameness– Subsequent PD of LF = resolved all lameness

Further Workup

• Ultrasound of RF suspensory– No abnormalities

• Radiographs of left and right front feet:– Breakover point is long, mildly contracted hoof

capsules bilaterally• FINAL DIAGNOSIS:– Bilateral forelimb lameness, blocks to a PD

• First, corrective farriery; Second, coffin/navicular bursa injections; Third, MRI

Front Foot Rads

5 months later (08/04/11)…

• Corrective shoeing had failed to produce improvement– PE wnl

• Lameness exam- no change EXCEPT…– Failed to improve to PD, Basisesamoid, Low-

4point, or high suspensory• Nuclear Scintigraphy was recommended

Bone Scan – Soft tissue phase

Bone Phase

Right Carpus Radiographs

Left Carpus Radiographs

R DMPLO L DMPLO

Further Examination• RF middle carpal block

– Minor improvement• LF middle carpal block

– Marked improvement in LF lameness– Exacerbated the RF lameness – No improvement with RF suspensory or Median/Ulnar block

• FINAL DIAGNOSIS: Bilateral Front limb lameness, Carpal Osteoarthritis of the LF Carpometacarpal and middle carpal joints– Bute and handwalking for a week– Intra-articular steroid and hyaluronic acid injections, carpi

• 08/16/2010, Recheck – 10 mg of hyaluronic acid and 20mg of triamcinolone into the

intercarpal joint, bilaterally• 09/07/2010, Recheck– Had been sound at the walk– At the trot, short steps RH and LF– PE: mild abrasion over the LF carpus, all else wnl

• Mild bilateral forelimb lameness, 2/5• Mild RH lameness, 2/5

– Intra-articular injections of triamcinolone bilaterally in the TMT and DIT joints

The Rest of the Story (10/06/10, Recheck)

• Owner notes that Hal is comfortable, until under saddle, at which time he is mild RF lame

• Bilateral front limb, Distal Flexion: ++• Lunging

– Tracking right: 3/3 RF lameness– Tracking left: 2/5 RF Lameness

• R Shoulder block = no improvement• RF basisesamoid block

– 80% improvement on hard surface, 100% on soft– With rider, 50% improvement on straight line, little improvement when tracking right

• Thoracic spine rads: wnl• Right Fetlock rads: large osteophyte, DM aspect of P1

– RF coffin/fetlock joint treated with triamcinolone/HA

Right Fetlock Radiographs

DMPLO

DLPMO

• Arabian horses were found to be over-represented for severe DJD of the carpometacarpal joint– 74% Arabs vs. 12% non-Arab horses

• Mean age of diagnosis in Arab horses was 14.4 years

• Trauma was known in 34% of the Arabs• Conformational defects not noted in all but one

horse

• Absence of a palmar articulation between MC3 and MC2 was observed in 48% of Arabian horses vs. 12% in non-Arabs

• Ultrasonographically, the interosseus ligament was visible in the horses without the palmar articulation

• Breed differences in carpometacarpal joint articulation may be responsible for the increased frequency of this condition in Arabs

• Ultrasound may be a valuable screening tool for predisposed animals

• Found Quarter Horses to be significantly over-represented for CMC DJD in their population

• Consistent clinical findings

• Radiographic findings– Proliferative new bone growth on MC2 extending to MC3, C2, and

C3– Narrowing of the CMC joint space– Subchondral bone lysis of MC2 and/or C2

• Outcomes– Left untreated, none of the horses returned to

work and 4/5 were euthanized for lameness within 3 years

– 9/12 treated horses saw improvement, but only for a mean of 4.6 months

– 6/14 of the treated horses were euthanized for lameness within 4 years