Regeneration game
Your Horse 13 Aug-9 Sept 2009
Stem cell therapy is offering new hope to owners of all types of horses with damaged tendons, offering a better quality of repair to injuries
Words: Andrea Oakes
Healthy tendons give your horse the bounce he needs for equine work and play. These tough, fibrous bands act like a set of well-oiled springs, storing an enormous amount of ‘elastic energy’ as the horse moves before releasing it to power him forwards into another stride.
It’s no wonder that damage to these vital structures is such a big deal. A slow healing process, lengthy rehabilitation and – most worryingly – a high risk of recurrence, have traditionally spelled doom and gloom to owners of horses with tendon problems.
But an innovative treatment for certain tendon injuries is offering new hope for sports and leisure horses alike. It’s the prospect of a better-quality (rather than quicker) repair that’s persuading many owners to opt for equine stem cell therapy, a hi-tech but surprisingly straightforward procedure.
Far from being a futuristic fantasy, stem cell therapy is proving an effective reality in the successful treatment of such conditions. And it’s not just our horses’ tendons that stand to benefit from this exciting technology. Current research could soon lead to a host of new horse health solutions coming to a veterinary practice near you.
The trouble with tendons
To understand why stem cell therapy is considered a breakthrough in the treatment of tendon problems, it’s worth looking at why the repair of these structures can be so problematic.
A horse’s tendons consist of many elastic fibres, made primarily of collagen, which run in parallel. These fibres have some degree of stretch, but excess pressure – for example if the horse works hard over rough ground, lands awkwardly over a fence or is trained excessively when out of condition – can cause them to overstretch and tear. When fibres tear, the horse is said to have sprained a tendon.
There are many treatment options, typically involving reduction of the resulting inflammation followed by lengthy rest and rehabilitation. The injured tendons can heal, slowly, but do so by producing ‘scar tissue’, which is less flexible than normal tendon material. The horse may not be as athletic as he was and is at greater risk of re-injuring the tendon in the future.
So what’s different about stem cell therapy?
Veterinary surgeon David Mountford, chief operating officer at VetCell, the UK-based company that pioneered equine stem cell therapy in conjunction with the Royal Veterinary College, claims that it works on the basis of regeneration rather than repair.
“Stem cell treatment aims to promote regeneration of flexible tendon tissue rather than allowing less pliable and more injury-prone scar tissue to form,” he says. “Stem cells, for the first time, offer the prospect of a return to a fully functional tendon.”
Simple science
The basics of equine stem cell therapy can be grasped without too much scientific know-how. Most of the millions of cells that make up the equine body have a specialised job to do, and they’re unable to change their function or repair themselves – which is fine until injury or illness strikes.
According to vet David Mountford, what makes a stem cell unique is its ability to renew itself and give rise to different cell types. “Stem cells are the body’s own repair kit, allowing the regeneration of tissue that has been damaged,” he says. “One particular type of stem cell, the adult mesenchymal stem cell, has the potential to develop into a range of tissue types including tendon, ligament, bone and cartilage.”
When these mesenchymal stem cells are implanted directly into the injury site, explains David, they have the ability to recreate healthy tendon tissue, providing an aid to the body’s natural healing process. What’s more, the source of this ingenious repair mechanism can be harvested from the injured horse itself.
“Bone marrow is a rich source of mesenchymal stem cells,” says David. “This is easily extracted from the breastbone (sternum) or hip while the horse is under sedation.”
However, before the extracted cells can do their work, they must first be processed at the VetCell laboratory.
“The stem cells are isolated and multiplied to in excess of 10 million cells before being suspended in bone marrow serum,” says David. “The cell suspension is then returned to the vet and, with the horse sedated and nerve blocked, the stem cells are injected, using ultrasound guidance, into the damaged area of the tendon.”
Back to work
While the horse rests in his stable for a week, the stem cells can adapt to their new environment. Daily walking exercise then stimulates their activity, encouraging them to change into tendon cells and start forming strong tendon fibres.
David stresses that there are no short-cuts on the road to rehabilitation. The healing process and gradual strengthening is likely to take months, even when stem cell therapy is used.
“It’s important to remember that stem cell therapy is designed to provide a better-quality repair, rather than a quicker repair,” he explains. “The controlled rehabilitation programme we recommend is fairly conventional, although it can be varied according to the severity of the injury and the horse’s future use. As with all rehabilitation, a vet should always be involved – especially at the point at which the pace is stepped up into trot and again into canter.”
This unique process of recreating healthy tendon tissue greatly enhances the horse’s chances of returning to athletic work – and staying sound. David highlights a recent study in which 168 horses from the gruelling sport of National Hunt racing were analysed following stem cell therapy for tendon injury.
“The data has identified that the re-injury rate after return to full work, in the three years following treatment, is 24% – compared to the 56% reported for horses that have undergone more traditional tendon treatment,” he says.
Counting the cost
VetCell claims that stem cell therapy has helped riding club horses and children’s ponies as well as racehorses and Olympic competitors. But is the treatment a viable option for every horse owner?
Chris Lehrbach, an equine surgeon at Chapelfield Veterinary Partnership in Norfolk – and one of the 300 or so vets trained by VetCell to carry out the procedure – believes it can be.
“I would recommend stem cell therapy as a first line of treatment, but the downside is the cost,” he says. “The treatment involves a scan, the collection of the bone marrow at our clinic and the culturing of it at the laboratory, followed by the implantation of the cells back at the clinic and possibly one or two follow-up scans. You’re looking at around £2,000, at least.”
The good news is that the treatment is covered under many insurance policies, and Chris reports no problems so far with insurance companies paying up.
“It’s not just a treatment for the high-level competition horse,” he explains. “If an owner wants the best long-term outcome – and their horse is insured or they can afford to pay otherwise – stem cell therapy seems to be, scientifically speaking, the best option.”
While the therapy is most often used to treat injuries of the superficial digital flexor tendons (the thick, flexible tendon that lies behind the cannon bone and can be felt from the back of the knee to the fetlock), Chris says it can also be used for a range of different tendon and ligament problems. Despite the encouraging success rates so far, however, he warns that it should not be considered a panacea.
“The treatment is most effective in the case of an acute, traumatic tendon tear – a one-off injury,” he says. “But, if the tendons are degenerating and are not up to the job anyway, stem cell therapy will not stop problems recurring.”
Increased understanding
Remarkably, the use of stem cell therapy to treat equine tendon problems has preceded that of similar injuries in humans. So it’s perhaps not surprising that few of us understand what it’s all about.
“We’ve all heard of stem cells, but many people don’t know what they are, or realise that the treatment is an option for their horse,” says Chris.
David agrees. “Some owners may be initially put off because they think that the treatment is highly complex and invasive, but it’s usually very straightforward and can be carried as a routine veterinary procedure,” he says.
Media scare stories haven’t helped.
“Stem cell therapy is sometimes mistakenly confused with cloning and the use of embryos, but the stem cell therapy used in horses has no connection with either,” adds David. “There are no embryos involved.”
According to David, the development of stem cell therapy for equine tendon problems was partly driven by need. “Tendon injuries in horses can be career-ending, so there’s always been a demand for an effective treatment,” he explains.
However, it’s the physical characteristics of an equine tendon injury, he says, that provide the ideal environment in which new tissue can generate. Therefore, in this case, the development of clinical veterinary medicine is way ahead of its human counterpart.
Future developments
Key areas of current development in equine stem cell therapy include enhanced fracture repair and the treatment of some specific joint injuries, offering hope for horses of all ages, abilities and breeds.
“There’s much exciting research, worldwide, looking at possible new stem cell therapies for horses,” explains David. “There are still some gaps in our knowledge regarding exactly how the stem cells work and how the treatments might be optimised, but these gaps are steadily being filled.
“Over the next few years, as more therapies are tested and become available to both human and veterinary patients, the technology will become mainstream and will be better understood by the general public,” he adds. The science may be new to many of us at the moment but, in the future, we’re likely to hear a lot more about the ability of stem cell therapy to help our horses recover from injury or disease.
Following the successes seen in equine stem cell therapy, trials in the repair of human tendon injuries are planned for early 2010. These will be conducted by VetCell’s parent company MedCell Bioscience and will focus on the Achilles tendon.
Professor Nicola Maffulli, a sports medicine and orthopaedic consultant said: “The move from clinical veterinary to human medicine is inspiring and unusual. We normally see the translation happening the other way around.”
READERS LIKE YOU:
Marsh Mayfly bounces back
Stem cell therapy has given international event horse Marsh Mayfly a second chance to shine.
The 12-year-old mare, known as Flower, had just secured fourth place at the 2007 Chatsworth International when she pulled up lame after finishing the final show jumping phase.
“We were devasted,” admits her owner, Ann Lawson, explaining that scans taken of Flower’s hot and swollen foreleg revealed fibre damage in the superficial digital flexor tendon. “However, our vet remained optimistic and recommended stem cell therapy. I’d heard about the treatment and it seemed to be successful, so we went ahead – and we also decided to put Flower in foal.”
Andrew Miller of the Ark Veterinary Centre in Lockerbie carried out the stem cell therapy, after which Flower was placed on a strict regime of controlled exercise.
“We adhered to the rehabilitation programme religiously until it came to the cantering,” says Ann. “Flower was too large by then for any faster work!”
Last summer Flower gave birth to a colt foal and was later able to resume exercise. In April she was fit enough to start competing again with Ruth Edge, her rider of seven years.
“She felt fit, keen and full of power,” says Ruth, referring to the mare’s three-star win at Burnham Market. “Flower is such a generous horse and it’s great to be back on board.”
Ann agrees, adding: “Flower’s leg seems fine after the treatment. I’d just like to see how it stands up to a four-star event.”
First published in Your Horse. To subscribe, visit www.yourhorse.co.uk
ends
Words: Andrea Oakes
Healthy tendons give your horse the bounce he needs for equine work and play. These tough, fibrous bands act like a set of well-oiled springs, storing an enormous amount of ‘elastic energy’ as the horse moves before releasing it to power him forwards into another stride.
It’s no wonder that damage to these vital structures is such a big deal. A slow healing process, lengthy rehabilitation and – most worryingly – a high risk of recurrence, have traditionally spelled doom and gloom to owners of horses with tendon problems.
But an innovative treatment for certain tendon injuries is offering new hope for sports and leisure horses alike. It’s the prospect of a better-quality (rather than quicker) repair that’s persuading many owners to opt for equine stem cell therapy, a hi-tech but surprisingly straightforward procedure.
Far from being a futuristic fantasy, stem cell therapy is proving an effective reality in the successful treatment of such conditions. And it’s not just our horses’ tendons that stand to benefit from this exciting technology. Current research could soon lead to a host of new horse health solutions coming to a veterinary practice near you.
The trouble with tendons
To understand why stem cell therapy is considered a breakthrough in the treatment of tendon problems, it’s worth looking at why the repair of these structures can be so problematic.
A horse’s tendons consist of many elastic fibres, made primarily of collagen, which run in parallel. These fibres have some degree of stretch, but excess pressure – for example if the horse works hard over rough ground, lands awkwardly over a fence or is trained excessively when out of condition – can cause them to overstretch and tear. When fibres tear, the horse is said to have sprained a tendon.
There are many treatment options, typically involving reduction of the resulting inflammation followed by lengthy rest and rehabilitation. The injured tendons can heal, slowly, but do so by producing ‘scar tissue’, which is less flexible than normal tendon material. The horse may not be as athletic as he was and is at greater risk of re-injuring the tendon in the future.
So what’s different about stem cell therapy?
Veterinary surgeon David Mountford, chief operating officer at VetCell, the UK-based company that pioneered equine stem cell therapy in conjunction with the Royal Veterinary College, claims that it works on the basis of regeneration rather than repair.
“Stem cell treatment aims to promote regeneration of flexible tendon tissue rather than allowing less pliable and more injury-prone scar tissue to form,” he says. “Stem cells, for the first time, offer the prospect of a return to a fully functional tendon.”
Simple science
The basics of equine stem cell therapy can be grasped without too much scientific know-how. Most of the millions of cells that make up the equine body have a specialised job to do, and they’re unable to change their function or repair themselves – which is fine until injury or illness strikes.
According to vet David Mountford, what makes a stem cell unique is its ability to renew itself and give rise to different cell types. “Stem cells are the body’s own repair kit, allowing the regeneration of tissue that has been damaged,” he says. “One particular type of stem cell, the adult mesenchymal stem cell, has the potential to develop into a range of tissue types including tendon, ligament, bone and cartilage.”
When these mesenchymal stem cells are implanted directly into the injury site, explains David, they have the ability to recreate healthy tendon tissue, providing an aid to the body’s natural healing process. What’s more, the source of this ingenious repair mechanism can be harvested from the injured horse itself.
“Bone marrow is a rich source of mesenchymal stem cells,” says David. “This is easily extracted from the breastbone (sternum) or hip while the horse is under sedation.”
However, before the extracted cells can do their work, they must first be processed at the VetCell laboratory.
“The stem cells are isolated and multiplied to in excess of 10 million cells before being suspended in bone marrow serum,” says David. “The cell suspension is then returned to the vet and, with the horse sedated and nerve blocked, the stem cells are injected, using ultrasound guidance, into the damaged area of the tendon.”
Back to work
While the horse rests in his stable for a week, the stem cells can adapt to their new environment. Daily walking exercise then stimulates their activity, encouraging them to change into tendon cells and start forming strong tendon fibres.
David stresses that there are no short-cuts on the road to rehabilitation. The healing process and gradual strengthening is likely to take months, even when stem cell therapy is used.
“It’s important to remember that stem cell therapy is designed to provide a better-quality repair, rather than a quicker repair,” he explains. “The controlled rehabilitation programme we recommend is fairly conventional, although it can be varied according to the severity of the injury and the horse’s future use. As with all rehabilitation, a vet should always be involved – especially at the point at which the pace is stepped up into trot and again into canter.”
This unique process of recreating healthy tendon tissue greatly enhances the horse’s chances of returning to athletic work – and staying sound. David highlights a recent study in which 168 horses from the gruelling sport of National Hunt racing were analysed following stem cell therapy for tendon injury.
“The data has identified that the re-injury rate after return to full work, in the three years following treatment, is 24% – compared to the 56% reported for horses that have undergone more traditional tendon treatment,” he says.
Counting the cost
VetCell claims that stem cell therapy has helped riding club horses and children’s ponies as well as racehorses and Olympic competitors. But is the treatment a viable option for every horse owner?
Chris Lehrbach, an equine surgeon at Chapelfield Veterinary Partnership in Norfolk – and one of the 300 or so vets trained by VetCell to carry out the procedure – believes it can be.
“I would recommend stem cell therapy as a first line of treatment, but the downside is the cost,” he says. “The treatment involves a scan, the collection of the bone marrow at our clinic and the culturing of it at the laboratory, followed by the implantation of the cells back at the clinic and possibly one or two follow-up scans. You’re looking at around £2,000, at least.”
The good news is that the treatment is covered under many insurance policies, and Chris reports no problems so far with insurance companies paying up.
“It’s not just a treatment for the high-level competition horse,” he explains. “If an owner wants the best long-term outcome – and their horse is insured or they can afford to pay otherwise – stem cell therapy seems to be, scientifically speaking, the best option.”
While the therapy is most often used to treat injuries of the superficial digital flexor tendons (the thick, flexible tendon that lies behind the cannon bone and can be felt from the back of the knee to the fetlock), Chris says it can also be used for a range of different tendon and ligament problems. Despite the encouraging success rates so far, however, he warns that it should not be considered a panacea.
“The treatment is most effective in the case of an acute, traumatic tendon tear – a one-off injury,” he says. “But, if the tendons are degenerating and are not up to the job anyway, stem cell therapy will not stop problems recurring.”
Increased understanding
Remarkably, the use of stem cell therapy to treat equine tendon problems has preceded that of similar injuries in humans. So it’s perhaps not surprising that few of us understand what it’s all about.
“We’ve all heard of stem cells, but many people don’t know what they are, or realise that the treatment is an option for their horse,” says Chris.
David agrees. “Some owners may be initially put off because they think that the treatment is highly complex and invasive, but it’s usually very straightforward and can be carried as a routine veterinary procedure,” he says.
Media scare stories haven’t helped.
“Stem cell therapy is sometimes mistakenly confused with cloning and the use of embryos, but the stem cell therapy used in horses has no connection with either,” adds David. “There are no embryos involved.”
According to David, the development of stem cell therapy for equine tendon problems was partly driven by need. “Tendon injuries in horses can be career-ending, so there’s always been a demand for an effective treatment,” he explains.
However, it’s the physical characteristics of an equine tendon injury, he says, that provide the ideal environment in which new tissue can generate. Therefore, in this case, the development of clinical veterinary medicine is way ahead of its human counterpart.
Future developments
Key areas of current development in equine stem cell therapy include enhanced fracture repair and the treatment of some specific joint injuries, offering hope for horses of all ages, abilities and breeds.
“There’s much exciting research, worldwide, looking at possible new stem cell therapies for horses,” explains David. “There are still some gaps in our knowledge regarding exactly how the stem cells work and how the treatments might be optimised, but these gaps are steadily being filled.
“Over the next few years, as more therapies are tested and become available to both human and veterinary patients, the technology will become mainstream and will be better understood by the general public,” he adds. The science may be new to many of us at the moment but, in the future, we’re likely to hear a lot more about the ability of stem cell therapy to help our horses recover from injury or disease.
Following the successes seen in equine stem cell therapy, trials in the repair of human tendon injuries are planned for early 2010. These will be conducted by VetCell’s parent company MedCell Bioscience and will focus on the Achilles tendon.
Professor Nicola Maffulli, a sports medicine and orthopaedic consultant said: “The move from clinical veterinary to human medicine is inspiring and unusual. We normally see the translation happening the other way around.”
READERS LIKE YOU:
Marsh Mayfly bounces back
Stem cell therapy has given international event horse Marsh Mayfly a second chance to shine.
The 12-year-old mare, known as Flower, had just secured fourth place at the 2007 Chatsworth International when she pulled up lame after finishing the final show jumping phase.
“We were devasted,” admits her owner, Ann Lawson, explaining that scans taken of Flower’s hot and swollen foreleg revealed fibre damage in the superficial digital flexor tendon. “However, our vet remained optimistic and recommended stem cell therapy. I’d heard about the treatment and it seemed to be successful, so we went ahead – and we also decided to put Flower in foal.”
Andrew Miller of the Ark Veterinary Centre in Lockerbie carried out the stem cell therapy, after which Flower was placed on a strict regime of controlled exercise.
“We adhered to the rehabilitation programme religiously until it came to the cantering,” says Ann. “Flower was too large by then for any faster work!”
Last summer Flower gave birth to a colt foal and was later able to resume exercise. In April she was fit enough to start competing again with Ruth Edge, her rider of seven years.
“She felt fit, keen and full of power,” says Ruth, referring to the mare’s three-star win at Burnham Market. “Flower is such a generous horse and it’s great to be back on board.”
Ann agrees, adding: “Flower’s leg seems fine after the treatment. I’d just like to see how it stands up to a four-star event.”
First published in Your Horse. To subscribe, visit www.yourhorse.co.uk
ends