Weeks 10-12 at Stevens Equine

There have certainly been some interesting cases in my last few weeks at Stevens Equine.  Most of the cases have been the usual lameness exams but there has also been some dental work, colics, and a choke.  The choke resolved well after the horse was sedated and a nasogastric tube was passed.  The obstruction was disintegrated by repeatedly lavaging it with water.  I could see why aspiration pneumonia is a common secondary problem with it, but the horse recovered well and without complications.  We also saw another horse at the show prior to the choke that likely had an esophageal stricture because while it ate, its neck would become ventrally distended just cranial to where it joined its chest.  It had not been a problem for the horse, but Dr. Stevens recommended feeding it many small meals throughout the day and keeping an eye on it.

Another interesting case that we have been treating is a retired show horse that had a bout of laminitis earlier in the summer.  She has been treated with supportive care and kept on stall rest, and has been shod therapeutically with the addition of equi-pak and a pad.  Oddly, she foundered more severely in her hind feet.  We re-checked her again last week and found that she had developed an abscess in her right hind hoof just under the pedal bone.  Furthermore, radiographs revealed that she had some osteomyelitis of her distal P3.

Rather than euthanizing her, the owners elected to have the affected area opened and debrided through a heavily sedated standing procedure.  So, after performing a high four point nerve block and an intravenous regional perfusion with amikacin, the sole was opened and the nonviable tissues were debrided.  The site was lavaged thoroughly then packed with pivodone-soaked gauze and the distal limb was wrapped with a pressure wrap.  As of when I left on Saturday, she was receiving daily regional perfusions with amikacin with bandage changes and was going to have a hospital plate placed on the hoof that day.

Jamshidi needle, 20 cc syringe pre-loaded with sodium

heparin, and scalpel blade for stab incision

One other very interesting case was one that I have written about earlier.  That horse presented for lameness and after a thorough lameness exam, ultrasound revealed that his pain likely stemmed from an old injury of the DDFT that had mineralization within the lesion.  The injury was treated with shockwave therapy then stem cells were harvested from the horse to place in the affected region.  I have never seen stem cell collection prior to that, so it was very interesting to watch.

Common places to harvest stem cells from include from adipose tissue deposits around the tail head as well as marrow from the ilium or sternum.  Dr. Stevens usually collects them from the sternum, as slight scarring is possible.  First, the sternum was viewed via ultrasound to gain visualization of the individual sternebrae.  The horse was then sedated and the area was clipped and scrubbed.  The area between the point of the elbows to approximately 4 cm caudally was blocked with carbocaine.

Placement of local anesthetic (Carbocaine)

Stab incision made over sternebrae

After the region was anesthetized, a stab incision was made through the skin and underlying tissues and a Jamshidi needle was placed into the sternum.  A Jamshidi needle is basically a bore, and is an 11 gauge 4” needle that penetrates the sternebrae when it is rotated.  A syringe that is pre-loaded with heparin is then attached to the Jamshidi needle and 8-10 ml of marrow is aspirated.  The needle was then removed and the incision was closed with skin staples.  A blood sample was also collected for the cryopreservation of stem cells.  The procedure went very smoothly, then we packed the collection with ice and shipped it overnight to Advanced Regenerative Therapies.  There, the cells are processed and expanded, then the expanded stem cells are returned to be injected in the site of injury.

About 10 days later, the stem cells were returned and were placed via ultrasound-guided injection into the tendon.  It is a very precise procedure, and we had difficulty because this horse tends to sway when he is sedated.  Ultimately, the placement was successful and hopefully the horse recovers well and returns to competition.

Jamshidi needle placed for marrow collection

Syringe attached to Jamshidi needle and aspirated

Ultimately, I cannot believe that this summer is almost over already!  I have learned a tremendous amount through this experience and would like to thank Dr. Stevens and Christy for everything that they have done as well as Dr. Schott for giving us all the opportunity to expand our learning through this program.