"I have seen much luck with it," he states. "Right now I use it more for bucked shin and shin fractures," he says. "I have
used it on shins because I rather do that than pin fire these horses. I'm a big skeptic. As far as success, I think we are
too early to determine how successful we'll be as far as stimulating the healing. We are blocking some pain, but are we actually
getting some benefits from it I'm not sure. Following with some radiographs we have seen some evidence of healing, but these
horses are also getting quite a bit of time away from training. For me, the jury is still out as to whether I am getting any
benefit from it or not."
Doug Herthel, DVM, Alamo Pintado Equine Clinic in Los Olivos, Calif., says shock wave therapy seems to be efficient in improving
suspensory ligament damage, specific sesamoid lesions and bone spurs located between the sesamoid bones.
"We use it for a multitude of problems," says Keith Merritt, DVM, Wauconda, Ill. "We use it for tendonitis, whether its superficial
flexor tendon or deep digital flexor tendon (DDFT), for suspensory desmitis (front or hind leg), for collateral ligament problems,
distal sesamoid ligaments, cortical bone fracture (cracks), DJD of the fetlock, knee, and hock, for the cranial horn meniscus
problems in the stifle, chronic sore backs and sacroiliac problems and DJD of the cervical spine."
But despite the success of therapy, it has its pitfalls, too. Merritt has considered the failures as well as the successes.
Most of the failures he has experienced with tendons occurred with at least a six-week-old tear within the tendon before he
initiated treatment. The best tendon responses were the ones he treated immediately after the injury, and he did not begin
ESWT until 10 days to two weeks after the incident. At that time, after the tendon had been torn and after he got some sort
of medication to it, started shock wave therapy yielded a very high percentage of improvement.
"On front-leg suspensory desmitis, it's phenomenal, the best thing since sliced bread," Merritt says. "For hind-leg suspensory
desmitis, I don't think there is any great treatment for that because it works on some, and some it does not. For navicular
disease, 50 percent of the horses will respond. For DDFT at the insertion to P3, 100 percent of those cases we've got are
sound, and they've stayed sound for at least a year and half."
The youngest case that McCarroll treated was a 4-year-old Quarter Horse that was used for reining. He came up lame a month
before a reining futurity. He attempted a treatment on him, but it did not work. However, within three months he was at another
futurity. He showed successfully and was sound. He had radiographic evidence of the dissolution, improvement of cyst of the
"In navicular disease, I really think a lot of caudal heal pain is associated with the ligamentous attachment to the navicular,
the coffin bone, and 2nd phalanx, McCarroll says. "A lot of the tearing occurs, which leads to pain. The attachment of the entire ligament along the
polar plantar border is apparently compromised. If we can improve the strength of the attachment at that area, I think we
can get the horse feeling a lot more comfortable. On the wings of the navicular bone, medially and laterally where you see
spur formation, a lot of times that means there is damage to the navicular collateral ligament or suspensory ligament up the
leg. If you treat those areas, they seem to improve."
Snow says in the navicular cases, horses that seem to respond well had moderate changes, without any gross flexor cortex abnormalities
or osteophytes in the navicular ligament, any spurs on the wings. Horses with an increased number and size of vascular channels
— but did not have palmar cortex or spurs — seemed to respond well. About 79 percent (of 110 head) returned to full range
of previous use, he says.
Snow used shock wave therapy on horses with insertional desmopathies at the proximal suspensory ligament with good results,
too. But animals with tarso-metarsal and distal inter-tarsal osteoarthritic problems showed poor results.