Is your horse showing signs of girthiness? Also known as girth aversion or cinch sensitivity, horses that are girthy express signs of discomfort when they are being saddled.
A girthy horse may respond to having a girth tightened by expressing various behaviors ranging from tossing their head, biting, swishing the tail, stomping their hooves, and moving away from their handler. 
Such behaviours can be problematic for horse owners, handlers, and grooms to manage. These behaviors could also be a sign of an underlying health problem, such as gastric ulcers.
Girthiness may also be caused by active pain, improperly fitting tack, other health conditions, or the anticipation of physical pain based on past experience. 
If your horse shows signs of girth aversion, have them assessed by a veterinarian to determine if a health problem is causing the issue. It is also important to have their saddle fit evaluated to rule out any pain that might be caused by a poorly fitted saddle.
Girthiness in Horses
Girth aversion (or cinch aversion) refers to a horse’s adverse behavior to having a saddle girth or other training equipment tightened around the belly.
Although behaviors associated with girthiness can occur in different circumstances, some horses are particularly prone to reacting when being tacked up or when their abdomen is touched. Your horse may even become girthy upon seeing a saddle.
Girthy behaviour is a response to discomfort.  If these behaviors continue, they can be unsettling and potentially dangerous. Without intervention, the aversive behaviors may worsen over time.
Identifying specific causes of girth aversion can be challenging for horse owners and researchers. However, various contributing physical and behavioral issues have been identified in horses. 
According to a 2019 research study that examined the problem in 37 male and female horses of various breeds and ages:
- 12 horses had stomach ulcers
- 10 presented with had spinal osteoarthritis or osteoarthritis-related problems
- 11 had other physical issues such as tumors or urinary tract infections
- 3 displayed behavioral resistance during girthing 
How you address girth aversion will depend on the cause of the condition and may involve rest, medications, therapies, dietary and management changes, changes to the tack utilized, and behavioral interventions.
The exact number of horses that display an aversion to having the girth tightened is unknown. However, in a survey of horse owners, 34.2 percent reported abnormal behavior in their horses during tacking-up and mounting. 
Google reports that there are over 8,100 searches for girthiness in the US every month.
Anecdotally, girthy behaviour is a common clinical observation although it is rarely the reason owners present their horses for veterinary assessment. 
Over a 12-year period, 0.09% of the total number of horses presenting to UC Davis were noted to show signs of girth aversion. 
Common signs of girth aversion include: 
- Turning and looking at the area on the belly where the girth is positioned
- Biting the person who is tacking the horse up
- Biting at objects such as the stall door
- Nodding the head
- Swishing the tail
- Pinning the ears backward
- Sucking in air
- Kicking out
- Moving away
- Humping up of the back
Note: Signs of pain can be nonspecific as some horses show general behavioral changes, regardless of the cause/type of pain. 
Accurately diagnosing the cause of girthiness often requires a systematic approach to rule out potential health problems. 
Diagnosing girth aversion in your horse may require veterinary tests and a saddle fitting evaluation. 
This test is used to check for ulcers in the stomach and involves placing a three-meter-long scope down the esophagus and into the stomach to visualize both the squamous and glandular mucosal surfaces.
A lameness exam is conducted to determine if your horse is experiencing pain in the soft tissues or joints.
This exam typically involves evaluating the horse while standing and during movement, completing hoof and flexion tests, and in some cases using diagnostic anesthesia (nerve and joint blocks) and or imaging (radiographs, ultrasound, MRI, and other tests).
Saddle Fitting Evaluation
Consult with a saddle fitting specialist to evaluate equipment issues that could be causing pain and aversion to the girth.
Pain caused by saddle-related issues may be due to any of the following:
- An incorrectly positioned saddle (ie. saddle sits too forward)
- Poor saddle fit (ie. saddle is too narrow or too wide)
- A damaged saddle (ie. saddle has a broken or twisted tree or is has uneven flocking in it) 
The exact causes of girthiness is often difficult to identify. However, behaviors associated with girth aversion may be related to the following: 
Gastric or Colonic Ulcers
Anecdotally, horse owners often report that girthiness is associated with gastric ulceration, which can cause stomach discomfort.  Hindgut issues or colonic ulcers may also cause pain that makes girthing uncomfortable.
As previously mentioned, a 2019 study found that 32% of horses presenting for girthiness were diagnosed with gastric ulcers. 
It’s important to note that not all horses with gastric ulcers show signs of girth aversion. 
Some horses may experience discomfort when the girth is on/tightened due to pressure exerted on anatomical structures located beneath the saddle and girth.
Girth aversion may be due to discomfort in the areas where myofascial trigger points are located and in the cutaneous muscle.
Myofascial Trigger Points (MTrPs)
Myofascial trigger points are known as hyperirritable spots in the skeletal muscle that contain palpable nodules in tight bands of muscle fibers. In a study of 38 horses, myofascial trigger points were assessed in the pectoral region. 
Researchers palpated the MTrPs on the horses to assess their behavioral reactions and assigned a severity score for their reaction (mild, moderate, or severe).
Horses with an owner-reported history of girth-aversion behavior demonstrated increased reactivity to palpation (had a higher severity score) compared to horses without a history of girthiness. 
A study of 12 horse cadavers determined that tactile stimulation of the skin overlying the cutaneous muscle is associated with a reflex muscular contraction that causes twitching in this area of skin (panniculus reflex).
Continuous stimulation of the panniculus reflex may occur due to the pressure exerted by tack and could play a role in consistent sensitivity to the girth in some horses. 
Anticipation of Pain During Ridden Exercise
A study that collected information from 66 horse owners found that 34.2% of repondants indicated that their horses displayed abnormal behavior during tacking-up and mounting.
Recognition of such behaviors is important, because it may reflect anticipation of pain under saddle and during ridden exercise.
Potential causes of pain during exercise may be due to: 
- Physical Issues: Includes a wide range of health problems such as gastric ulcers, musculoskeletal issues, and others.
- Improper Saddle Fit: Poor fitting saddles are a known cause of poor performance, contributing to tension and improper alignment in the back muscles.
- Girth Materials/Tension: Materials with less elasticity, higher tension, and narrow contours may be less comfortable for horses to wear than materials with increased elasticity, lower tension, and wider contours. 
Horses with issues or injuries related to their musculoskeletal system (bones, muscles, joints, ligaments, and tendons) may exhibit girthy behavior. 
In a 2019 study of 37 horses that demonstrated girth aversion, some had musculoskeletal problems including: 
- Thoracic and lumbar vertebral osteoarthritis
- Cervical vertebral osteoarthritis
- Bone spavin
- Front limb lameness
A study of 77 horses with pain originating from their vertebral column found they were prone to reacting when the girth was tightened or had decreased