Horse Stifle Injuries: Prevention, Causes, Symptoms, and Treatment

Table of Contents

Horse Stifle Injuries: Prevention, Causes, Symptoms, and Treatment

Table of Contents

The horse’s stifle joint, often compared to the human knee, is one of the most complex joints in the equine body. Unfortunately, its intricate structure and role in supporting a horse’s weight make it vulnerable to a variety of injuries. 

FEI Dressage European Championship Riesenbeck 2023. Copyright ©FEI/Leanjo de Koster

A stifle injury can range from soft tissue injuries involving the medial patellar ligament and posterior cruciate ligaments to more severe cases like meniscal tears and subchondral bone cysts. 

For horse enthusiasts, especially those involved in barrel racing or caring for younger horses, stifle lameness (a typical sign of stifle injuries) is a cause for concern.

While advancements in diagnostic methods, from flexion tests to arthroscopic techniques for both diagnostic and therapeutic purposes, have allowed for more accurate pinpointing of stifle disorders, the sheer variety of issues makes diagnosis and treatment a multifaceted process. 

Treating stifle injuries often means exploring various options, from injections to stem cell therapy. But with the right knowledge and understanding of the stifle in horses, one can navigate these challenges effectively.

In this article, we’ll look more closely at horse stifle injuries, discussing causes, symptoms, and how they can be prevented. We’ll also shed some light on a natural remedy that’s garnering attention in the equestrian community. Let’s get started! 

What is a Horse Stifle Injury?

The stifle joint is the largest joint in a horse’s body and is quite often compared to the human knee. Situated at the upper hind leg, it connects the femur (thigh bone) to the tibia bones. Its complex structure includes three patellar ligaments, collateral ligaments, and the crucial menisci, which cushion the joint. 

Courtesy of Wikipedia

This joint is supported by the surrounding quadriceps muscles, which play a significant role in the movement of the horse’s hind end. The stifle joint facilitates bending and straightening movements, ensuring that a horse can run, jump, and perform other athletic activities normally. 

Defining Stifle Injury

Stifle injury in horses refers to any damage or disorder that affects the stifle joint and its components. This could range from soft tissue injuries involving the medial patellar ligament or cruciate ligaments to more severe conditions like meniscal injuries or bone cysts (swelling-like structures that develop below the articular cartilage surface of joints).

Symptoms like stifle lameness arise when these injuries or disorders impede the joint’s function. It’s important to recognize that not all stifle issues result from traumatic injury; some could be due to repetitive stress or even developmental anomalies.

Symptoms of a Stifle Injury

Recognizing the symptoms of a stifle injury promptly can make a significant difference in the prognosis for recovery. Here are the primary signs to watch out for:

  • Lameness: This is the most evident sign. Depending on the severity of the injury, stifle lameness can range from intermittent to consistent and from mild to severe.
  • Swelling and Heat: The stifle joint and surrounding area may become swollen and feel warm to the touch, indicating inflammation.
  • Stiffness: The horse may exhibit stiffness when moving, particularly after resting for an extended period.
  • Altered Gait: A horse with a stifle injury might adopt an unusual gait pattern to compensate for discomfort. This could involve shorter strides or an unwillingness to flex the stifle fully.
  • Audible Clicking: In some cases, an audible click can be heard when the horse moves, especially if the injury involves the patellar ligaments.
  • Difficulty Standing or Rising: Especially in cases of upward fixation of the patella, a horse might struggle to stand up or move suddenly after resting.
  • Reactive Behavior: The horse might become reactive when the stifle area is touched, indicating pain or discomfort.

Causes of Horse Stifle Injuries

One of the most common causes of stifle injuries in horses is repetitive stress. This is particularly prevalent in sports horses or those participating in disciplines. For example barrel racing, which demand sharp turns and high-speed sprints. Over time, the continuous impact on the stifle joint can lead to soft tissue strains or even the development of subchondral bone cysts.

Traumatic injury, such as a severe blow to the hind end or an awkward landing after a jump. That can instantly damage the stifle joint’s components. Such injuries might result in tears to the collateral ligament or even fractures in extreme cases. Accidents in slippery conditions or when a horse’s foot gets trapped can lead to severe lameness and cause an immediate stifle injury.

Developmental Issues in Young Horses

Young horses, especially those undergoing rapid growth or with genetic predispositions, can experience stifle disorders. Conditions like upward fixation of the patella or locking stifle are not uncommon in foals and younger horses. Developmental issues might also arise from nutritional imbalances in a horse’s diet, causing irregularities in the joint’s development.

How Common Are Horse Stifle Injuries?

Stifle injuries are some of the most frequently diagnosed lameness issues in horses, especially those that take part in rigorous sporting activities. While exact statistics might vary based on the specific discipline or breed, equine veterinarians often encounter cases related to the stifle joint. 

For instance, in disciplines like show jumping, the rapid turns, jumps, and bursts of speed exert immense pressure on the stifle, making injuries more prevalent. Further research, such as  “Carnosine concentration in the muscle of thoroughbred horses,” (1) suggests that issues related to muscle performance can have direct implications on joint health, including the stifle. This further underscores the stifle joint’s vulnerability, even in well-conditioned equine athletes.

Is an Equine Stifle Injury Serious?

The seriousness of a stifle injury in horses can vary widely based on the nature and extent of the damage. Some only cause mild discomfort and require minimal intervention, while others can be debilitating.

Soft tissue injuries, for instance, might present as mild lameness, which could resolve with proper rest and targeted treatment. However, more severe cases like meniscal tears or significant damage to the patellar ligaments can result in pronounced stifle lameness, making it challenging for the horse to bear weight on the affected leg.

Potential Complications and Stifle Lameness

Untreated or improperly managed stifle injuries can lead to chronic arthritis or persistent lameness. Over time, the joint might suffer degenerative changes, making the issue worse. 

In some instances, the initial injury might trigger a cascade of problems in the body, affecting other joints due to altered gait patterns or compensatory mechanisms. This is why it’s always better to have a lame horse seen by a qualified vet as soon as possible, especially if you aren’t sure what the underlying cause might be. 

Another critical aspect to consider is the potential for recurrent injuries. Once a horse has sustained a stifle injury, it might be predisposed to future injuries. To help prevent this,  supporting joint health with products that contain carnosine can be beneficial. More on that coming up later! 

Preventing and Treating Horse Stifle Injuries

Prevention, of course, is always preferable to treatment. While it’s impossible to eliminate all risk factors, there are strategies horse owners can adopt:

Regular Exercise

Maintaining a consistent and controlled exercise program helps in keeping the horse’s muscles toned and joints lubricated. Just as important is making sure not to over-exercise and reintorducing exercise slowly if the horse has been recovering from any other injuries. Physical therapy is also a good idea in severe cases.  

Proper Training

Ensuring that the horse is trained with the correct techniques and not pushed beyond its limits is vital.

Treating stifle injuries can be intricate due to the complexity of the joint. It’s not just about addressing the immediate injury but also ensuring that secondary problems don’t arise from compensatory behaviors. For instance, a horse might start favoring one leg over another, leading to additional strain on other joints.

Enter Carnosine

Carnosine (a natural compound found in skeletal muscle) is gaining recognition for its potential benefits in supporting equine health. Its ability to act as an intracellular buffer, preventing rapid pH decline in muscles, makes it pivotal for equine athletes.

In fact, carnosine’s benefits extend far beyond muscle stability, as it plays a role in several physiological functions. These range from anti-oxidative and anti-inflammatory processes, to neurological, muscular, retinal, immunological, and cardiovascular functions. (2

Anti-inflammatory medication containing carnosine has also been shown to improve glucose metabolism and reduce cardiovascular risk factors, thanks to its anti-inflammatory, antioxidative, antiglycating, and chelating properties. (3)

Given carnosine’s key role in muscle function, it follows that it would also have potential advantages for horses, especially in the context of stifle joint injuries. Stifle injuries, often accompanied by inflammation, oxidative stress, and potential tissue degeneration, might benefit from carnosine’s anti-inflammatory and antioxidative properties. 

Its ability to stabilize muscle pH could potentially also help in reducing muscle spasms and discomfort that can accompany stifle injuries.

While direct research on carnosine’s benefits specifically in relation to stifle joint injuries in horses remains in its infancy, it shows extremely promising outcomes. It’s plausible that with adequate supplementation, horses could experience accelerated recovery, reduced inflammation, and improved muscle function post-injury.

The Power of CarnoGel®

Developed in collaboration with renowned institutions and equestrian athletes, CarnoGel® is a specialized sports gel that harnesses the power of carnosine. It accelerates muscle recovery and improves the health of tendons, ligaments, and joints without side effects. 

By applying CarnoGel® around 60 minutes before and after workouts, horse owners can provide their equine companions with the support they need to recover from stifle injuries and improve their overall performance.


Stifle injuries in horses are not only painful for the animal but also a source of concern for horse owners and trainers. The complex nature of the stifle joint and its critical role in supporting the horse’s body weight and facilitating movement makes injuries to this area particularly challenging.

However, with an understanding of the symptoms, horse owners can detect issues early on and seek appropriate interventions and treatment options. While traditional treatments and rest play a pivotal role, it’s promising to see a joint supplement like CarnoGel® entering the market. 

Natural ingredients like carnosine offer a complementary approach to supporting the health and recovery of our beloved equine companions.

For those involved in the equestrian world, it’s reassuring to know that advancements in equine care continue to evolve. Products like CarnoGel® represent a blend of tradition and innovation, bringing together the best of both worlds to ensure our horses receive the best care possible.


(1) Carnosine metabolism and function in the thoroughbred horse. 

(2) Important roles of dietary taurine, creatine, carnosine, anserine and 4-hydroxyproline in human nutrition and health. 

(3) Use of carnosine in the prevention of cardiometabolic risk factors in overweight and obese individuals: study protocol for a randomised, double-blind placebo-controlled trial.