Boone Needs New Bolton Center's Care: August 23 - September 4
New Bolton Center veterinarians treating Boone have diagnosed a bone infection in the fetlock joint of his right hind leg, which caused him to be lame.
Our Foal Cam colt was at New Bolton Center for more than a week undergoing tests and treatment, including surgery and aggressive antibiotics.
“Boone is doing well,” said Dr. Corinne Sweeney, Associate Dean of New Bolton Center. “He is stable, and responding to treatment.”
Diagnostic tests – including a series of radiographs and ultrasounds, as well as blood and fluid analysis – confirmed an infection in the lateral sesamoid bone, a small but vital structure in the fetlock joint. Boone underwent arthroscopic surgery to flush and examine the joint, and he received daily injections of antibiotics concentrated in the affected area for 10 days.
“The lab tests confirm that we are winning against the infection,” said Dr. Megan Burke, a surgery resident and Boone’s primary care veterinarian. “Boone is completely sound on the leg. He is feeling much better and is comfortable.”
A Saturday Night Emergency
Boone has been living with his mother My Special Girl at Dr. Rose Nolen-Walston’s farm since July 24. Nolen-Walston, an Assistant Professor of Internal Medicine, adopted him in partnership with longtime trainer Lisa Fergusson.
Dr. Nolen-Walston and her family noticed that Boone was lame and his leg swollen on the night of Saturday, August 23. She brought him with his mother to New Bolton Center’s renowned Emergency and Critical Care team.
The clinicians on duty that night – including Dr. Burke and Dr. Michelle Abraham, a Resident in Emergency and Critical Care Fellow – took radiographs and performed ultrasounds, as well as blood and fluid tests. The bone was not fractured, the ultrasound did not show any soft-tissue injury, and there were no wounds or lacerations. However, blood and fluid tests indicated an infection, although at that time it was unclear exactly where.
Boone was given antibiotics and anti-inflammatory medication, and he and My Special Girl went back to Dr. Nolen-Walston’s farm for evaluation over the weekend.
Back to New Bolton Center
“He was no worse, but he was no better,” Dr. Nolen-Walston said a few days later. “We needed to go through more testing to pinpoint the problem and decide on a course of treatment.”
Boone and My Special Girl returned to New Bolton Center on Tuesday, August 26. Dr. Virginia Reef, Chief of New Bolton Center’s Section of Sports Medicine and Imaging, performed an ultrasound examination of his fetlock, but did not see a problem with his tendons or ligaments.
The next morning, Dr. David Levine, Staff Surgeon, assisted by Dr. Burke, performed minimally invasive arthroscopic surgery, using a video camera inserted into the joint to examine the cartilage and surrounding structures and to flush out the infected fluid.
After surgery, Boone received the first of 10 daily regional limb perfusions, in which high levels of antibiotics were delivered directly to the blood supply of the affected leg.
On Thursday, August 28, Boone was visibly improved, walking much more comfortably. But that afternoon he had an additional full series of radiographs. As the clinicians looked at the films, they clearly were very concerned.
“This is serious,” said Dr. Levine, examining the images of Boone’s complex fetlock joint. Visible was a dark grey circular area in the white image, indicating an infected abscess inside the bone.
The team decided to continue the aggressive regional antibiotic treatment throughout the Labor Day holiday weekend, and run more tests on Tuesday, September 2.
The blood tests confirmed that the infection was subsiding, and Boone was obviously feeling better, walking more easily without pain medications. He even bucked a bit on his way to radiology, and kicked the radiographic plate square in the middle, sending it flying.
“Well, he’s feeling a lot better,” said Dr. Burke, who was holding the plate.
The veterinarians decided to continue the course of regional antibiotics. “The plan now is for long-term antibiotics and continued reassessment,” Dr. Sweeney said.
The clinical team believes bacteria originally entered Boone’s body through his bloodstream and settled in the fetlock joint. Although New Bolton Center sees many patients with this type of infection, it is considered unusual.
Boone, along with My Special Girl, were discharged on Wednesday, September 3, and transported to trainer Lisa Fergusson’s barn in Cochranville, where he will have a month of stall rest and continued treatment. Boone will be on oral antibiotics for at least a month.
“Boone has settled in,” said Dr. Nolen-Walston. “He is doing great so far. He’s got one of the best temperaments I’ve ever seen in a foal his age.”
Throughout the days of tests and treatment, the New Bolton Center team continually remarked on Boone’s great personality, noting his tolerance and calm temperament. They also commented on how much he had grown.
On his five-month birthday, August 29, Boone stood 14.1 hands (57 inches) and weighed just over 400 pounds. He already is halter-trained, walking along easily when led.
While Boone was receiving state-of-the-art medical and surgical care at New Bolton Center, residents and interns participated in his treatment all along the way, from emergency to internal medicine to ultrasound and radiography to surgery.
“For me, it was interesting to see how well he responded to medical treatment,” Dr. Burke said.
“We will have to see how he does,” Dr. Burke said. “He will come back in a month and we will take another set of radiographs and run blood tests. If everything looks good, we can stop the oral antibiotics.”
Bone infections are serious and can take a long time to heal. Bone does regenerate, so the abscess created by the infection may fill in over time, Dr. Burke said.
“We don’t really know what is going to happen with the bone. We are pleased the infection is responding to the antibiotics," she said. “He is still growing, and so he has more regenerative capacity than an adult.”
We won’t know for years whether this infection will impact Boone’s performance, she said. “If he stays comfortable and sound,” Dr. Burke said, “we will be happy.”
To view more photos, please go to Penn Vet's Flickr page.
Gelding and Vaccinations: July 16
New Bolton Center veterinarians gelded Boone, our Foal Cam colt, on July 16.
The 20-minute procedure to remove the colt’s testicles was performed outside in Boone’s paddock at 3 p.m. on a cool, sunny afternoon. Boone’s mother, My Special Girl, was close at hand. Boone also received his first round of vaccinations against West Nile virus, tetanus, rabies and equine encephalitis as well as a routine de-worming medication to kill any potential internal parasites.
“The procedure went very well, and Boone is doing just fine,” said Dr. Regina Turner, Associate Professor of Reproduction and Behavior at Penn Vet's New Bolton Center. Dr. Turner performed the procedure with Dr. James Myers and Dr. Jenn Linton, both residents in reproduction at New Bolton Center.
Boone was gelded when he was just shy of four months old. Although it is traditional to geld horses when they are around 8 to 12 months old, there is no evidence that waiting until colts are a year old offers any benefit. Dr. Turner indicated that more owners and veterinarians have been opting to geld horses at a younger age as the procedure is simpler when the animal is younger.
“There are fewer complications, less bleeding, and less swelling, because the testicles are so small. They recover from it very quickly,” Dr. Turner said. “The whole process often seems to be easier on the foal when the procedure is done at a younger age.”
Since Boone will be moving to a new home at Dr. Rose Nolen-Walston’s farm, our veterinarians also thought that it would be in Boone’s best interest to geld the colt before leaving New Bolton Center. That way, Boone would have the full attention of New Bolton’s veterinarians and staff while he recovered.
The day after the procedure, our colt had some mild swelling that was treated with anti-inflammatory medication. Two days after the procedure, the swelling had gone down but Boone had a low-grade fever. Since the surgery site looked so good, it was thought that the fever might be a response to the vaccinations that the colt had received. But just to be safe, Boone was placed on a few days of antibiotics and the anti-inflammatory medications were continued. By the next day the colt was fully recovered.
Horse owners routinely geld colts if they do not intend to have them reproduce, Dr. Turner said. Once colts go through puberty they can exhibit strong, stallion-like behavior, especially when near mares. This can make the stallion more difficult to handle and to ride. Some intact stallions require more experienced handling, and even reinforced fencing – things that may not be convenient or possible for some horse owners.
“The stallion behavior can be difficult to deal with for many horse owners,” Dr. Turner said. “Particularly if there are other horses around or if the stallion travels to large horse shows where there is a lot of exposure to other horses, especially mares.”
Height Check: Monday, June 30
measured 49.5 inches, or just over 12 hands, at three months old. Handler Ben Gessford did the measuring, while handler Rick Ladow kept our scamp Boone
in line, all at Penn Vet's Hoffman Center for Reproduction. Ben says he's had to let out the halter a couple of notches. Also, Boone's
bay little-foal coat is almost gone, with his grown-up dark grey shining through.
Physical Exam: Thursday, May 8
Dr. Michelle Abraham, a resident in internal medicine and neonatology, and Dr. Fe Ter Woort, a resident in ultrasound and cardiology, and Dr. Jamie Kopper, a hospital intern, all came to the Hofmann Center to examine Boone to check his heart murmur.
They said he seems just fine, healthy, and progressing normally.
"The murmur sounds like a normal, physiologic murmur, of the blood flow leaving the heart," Dr. Ter Woort said. "He's fine, totally fine. We are not concerned."
Penn Vet New Bolton Center veterinarians will continue to monitor his progress with regular examinations.
Health Update: Thursday, April 10
My Special Girl and Boone are progressing well. However, each of them has conditions that their veterinarians are monitoring.
Boone is thriving, weighing in at 137 pounds on April 10, up 33 pounds from his birth weight of 104. He is eating well, is very playful and has lots of energy. His front teeth, or incisors, are just coming in. “This is the expected growth rate for a normal, vigorous foal,” said Dr. Jonathan Palmer, Chief of New Bolton Center’s Neonatal Intensive Care Unit.
However, as described last week, Boone has four fractured ribs. Dr. Palmer also has detected a heart murmur.
Boone’s fractured ribs are healing well and as expected, Dr. Palmer said. The colt’s body has formed a protective cushion over each sharp end, called a seroma, which helps prevent the sharp ends from cutting other tissue. The seroma is formed by a thick, tough outer layer of fibrous tissue surrounding an inner pocket of fluid around the sharp ends. The bone also has begun to “remodel,” or re-form, so that the ends aren’t as sharp.
“As both processes proceed the fractured ribs become less and less a threat of causing further problems,” Dr. Palmer said.
Boone also has a heart murmur. Heard through a stethoscope, heart murmurs and are caused when the flow of blood through the heart becomes turbulent, Dr. Palmer said. This disrupted flow may occur as blood flows normally through the heart in young foals, referred to as a “flow murmur.” Flow murmurs, which are completely harmless, are very common, seen in 80 percent of foals during their first month of life, Dr. Palmer said. Murmurs also can be caused when connections in the heart are not completed, or when there is a heart defect.
“We will be following Boone’s heart murmur carefully during his first month to be sure it is harmless,” Dr. Palmer said. “But if it doesn’t fade and disappear we will do a complete heart examination including ultrasound imaging of his heart.”
My Special Girl is doing very well post-foaling, said Dr. Regina Turner, New Bolton Center Associate Professor of Reproduction. At her last examination, she was pooling urine in her vagina, which is common in mares after foaling, Dr. Turner said, and occurs because the birth canal is stretched during delivery of the foal. Last week Dr. Turner supervised as students performed a lavage to flush out the pooling urine in her uterus.
“The vast majority of mares self- correct this problem after they have their first postpartum ovulation,” Dr. Turner said. “We and our students will monitor her after she ovulates to be sure that this is the case for MSG. We have every expectation that it will be.”
Physical Exam: Tuesday, April 1
My Special Girl’s colt is thriving with normal vital signs and his prognosis is good. However, he has four fractured ribs, as confirmed today in an exam by Dr. Jonathan Palmer, Chief of Penn Vet New Bolton Center’s Neonatal Intensive Care Unit.
“It is not unusual for foals to fracture ribs when they are born, even when it's not such a tight squeeze,” said Dr. Palmer after the Tuesday morning examination. “The birth canal was tight, so we had been looking to see if he fractured any ribs.”
"The four fractured ribs are on the colt’s right side, which is better because they are farther from his heart," Dr. Palmer said. The ribs do not require repair, as they should heal on their own.
“It shouldn’t cause any long-term problems,” Dr. Palmer said. He checked the ribs on Sunday and Monday, but today some swelling appeared on the right side and he checked again.
He does not appear to be in too much pain, and was lying on his right side, sleeping this afternoon. “I’m sure it tingles and it bothers him a bit,” Dr. Palmer said."We don't want to give him any painkillers unless it's absolutely necessary. If he feels too comfortable, he might get overly rambunctious and fall on the fractured ribs, harming himself further."
The colt and My Special Girl will stay in the NICU at least until Monday, instead of leaving today as planned. Dr. Palmer said it takes about 10 days for the ribs to heal to the point that it will be safe to transport him to his new home.
“The bone will remodel and the edges will become less sharp so they are less likely to cut,” Dr. Palmer said. “During that time, the body will also form a protective barrier of fibrous tissue around the sharp ends. The ribs are not displaced. They just need time to heal.”
The danger is that a hard fall could fracture the ribs further. “Fractured ribs have sharp edges. Right now they are fairly aligned, but if he did something to misalign them a rib could puncture his heart or his lungs,” Dr. Palmer said.
The colt was born on Saturday, March 29, at 9:22, after a 22-minute labor. Dr. Palmer and his team had to assist in the birth, by lubricating the birth canal and pulling the foal through. The pulling by the clinicians did not cause the fractures. In fact their assistance probably prevented more from being affected.
Once it is safe for them to leave the NICU, My Special Girl and her foal will go to live at the Hofmann Center for Reproduction on the New Bolton Center campus. They will be confined to a stall there for at least a month, until the colt’s ribs fully heal. Then they will spend much of their time outside.
On April 1, My Special Girl also had her examination, and she is doing very well.