Girth pain, a common cause of suffering, poor behaviour and occasional reduced performance in saddle- and harness- horses

Ian S.Bidstrup
BVSc(Hons) MACVSc(Equine Medicine) CertVetChiro (AVCA) CertVetAcup (IVAS)
Student – Master of Chiropractic (Animal Chiropractic) RMIT University, Melbourne, Vic. Australia
e-mail: IBIDSTR@w140.aone.net.au

"Girthy" is a common term used by Australian horse owners (equates to "girthy" or "cinchy" in the USA) "Girthiness" is a syndrome where there is pain and objection when being saddled or girthed up.

"Girthiness" can be caused by painful withers, which commonly result from ill fitting saddles, from girth galls (sores) and from abnormal sensitivity of the chest behind the elbow. The latter group of girthy horses are by far the most common (>50% of the saddle horse population). The problem appears to originate from dysfunction of the costovertebral joints with referred pain that follows the path of the intercostal nerves. The aim of this paper is to discuss the importance of this problem and its treatment.

The history commonly includes symptoms associated with tightening of the girth. These range a very slight change in facial expression (a partial closing or tightening of the eyes or frown), to frantic, uncontrollable bucking and pigrooting and/or lying down. The most common symptom is attempting to bite the handler when the girth is being done up. There are often repeated attempts to bite at each progressive tightening of the girth. Horses sometimes inflate their chest to fix or splint and protect their ribs and do not relax until girthing has halted. They may grunt when being girthed or being ridden. In more extreme cases the horse throws itself on the ground or bucks violently once girthed. Most horses that are more than mildly affected have a shortened foreleg stride until warmed up and during this warm-up period may swish their tail and lay their ears back flat. Some refuse to move forward after girthing until the pain becomes duller. Often they resist leg aids, splinting their chest rather than responding properly to the aid. Some affected horses are obviously lame with generalised tightening of the shoulders and restricted scapular motion, resulting in a reduction of fore quarter power and coordination. Also, it is to be expected that race horses have their performance compromised by reduced oxygen uptake, as a result of restricted rib cage expansion.

Clinical examination: It is normal for horses to be ticklish behind the elbow but gentle stroking should remove any reaction to touch unless there is abnormal sensitivity. The skin sensitivity of girthy horses is coupled with overly reactive muscles in the region behind and above the elbow. Tapping the skin in this area on a girthy horse will usually provoke a local muscle twitch and sometimes the whole area will contract and the horse will drop its shoulder as it does so. In some cases the sensitivity may extend from the pectoral muscles in front of the shoulder right back to the mid-chest. However, usually it is centred around and behind one rib, most often the fourth or fifth. When present, the sensitivity extends down into the pectoral muscles, causing tightness and tenderness of the pectoral muscles, and up the intercostal space, extending under the shoulder blade. The sensitivity may be acute and easily elicited (such as is often seen with sensitive chestnut thoroughbreds), right down to being revealed only by deep palpation of the rib in low sensitivity horses, such as the very complacent warmblood.

Tapping of the local musculature usually produces a twitch response or local muscle contraction similar to that seen with trigger points, though on a much larger scale. The extent varies but can involve the serratus ventralis thoracis, the ascending pectoral and the whole triceps muscle group. In cases where the 1st through to the 5th ribs are involved the descending pectorals may also be affected. Trigger points are normally palpable in the trapezius muscles adjacent to the dorsal spinous processes’ of the vertebrae associated with the affected ribs.

Clinical examples

CASE 1, "PHOENIX" 15 year old, very placid, slow moving, thoroughbred gelding.

Presenting problem – Phoenix reacted badly to being girthed up each time that he was saddled up. Once the girth was fastened he would buck and move around in a very agitated manner, followed by lying down as if dead. He was very touchy around the area behind the elbow and disliked being brushed there, even with a soft brush. Once mounted Phoenix behaved like any normal horse other than that he would always hurry once turned for home.

History: Until 3 years ago no particular girthing problems were noted. Then Phoenix started looking around at the owner and backing up a little when being girthed. 18 months ago he began his current behaviour after being floated 1200km. Despite very gentle girthing his sensitivity to being girthed remained.

Two weeks before his first treatment I was treating another horse at the same property and noticed Phoenix in a yard nearby. What was notable about Phoenix was that his only piece of tack was a black surcingle around his girth. Questioning of the owner revealed the history and led to the current outcome. (The girth was being used to try to help Phoenix to get used to being saddled)

VISIT 1.22/7/99

Examination –Phoenix was reasonably relaxed and had a placid disposition. Palpation of the skin and muscles behind each elbow caused him to become agitated and produced a tremor in the associated skin and muscles. Each time the area was lightly tapped the local musculature went into spasm as if stimulated by an electric current. A section of the ascending pectoral muscle 15 cm behind the elbow was tender to touch and the muscle fibres were tight. The trapezius muscle above each shoulder blade was also tight and tender and had palpable knots or trigger points evident opposite the dorsal thoracic spinous processes of the 4th and 5th thoracic vertebrae. Pressure on these trigger points produced spasm of the girth area behind the elbow and through the trapezius muscle into the lower part if the wither. The tenderness was localised to the 4th and 5th intercostal spaces on the left and the 4th on the right.

Treatment Chiropractic adjustment of the costovertebral joints and vertebral motor units were performed using the dorsal spinous process of the 4th thoracic vertebra from the left and right and also the 5th on the left, as described under method. The pelvis and 2 lumbar, 5 cervical and 1 thoracic vertebra were also adjusted.

VISIT 2. 8/3/99

History Phoenix had been much less tender over the girth area and had laid down once when saddled but otherwise was much more comfortable about being saddled.

Examination Palpation and tapping of the area behind the elbow produced only a mild reaction. There was no detectable pectoral spasm and the trapezius muscle above the shoulder blade was only a little tight. Palpating the trapezius muscle did not produce spasm down into the lower wither (unlike the previous exam).

Treatment Chiropractic adjustment, of the costo-vertebral joints and vertebral motor units were repeated using the dorsal spinous process of the 4th thoracic vertebra from the left and right, as described under method. The pelvis and 2 lumbar ad 2 cervical vertebrae were also adjusted.

Clinical outcome (as reported by phone 16/7/99): Phoenix no longer reacts to girthing. Even a hard brush can now be used on the girth area behind his elbow. During rides he is more relaxed and, notably does not rush once turned for home.

CASE 2. "BEAUTY" 16 year old pony mare used by the Riding for the Disabled Association.

Presenting problem. Beauty was becoming increasingly dangerous when being saddled up. She viciously attempted to bite when being girthed, even in the gentlest manner. This made Beauty unsuitable to use, which was unfortunate as she had been a "wonderful pony for the disabled riders to use" in the past.

History. Beauty had been owned by the RDA for some 10 years and had always been moderately sensitive about being girthed up. Three years ago she was very forcefully girthed up by one of the helpers. Thereafter, she was very difficult about having her girth fastened. She used to lay her ears back and attempt to bite when being girthed. 15 months ago this problem came to a head when she savagely bit a helper, despite the helper being very gentle when fastening the girth. This savageness continued and has remained a problem up to the time of presentation. Treatment with long acting progesterone dulled this behaviour but did not change it in the long term. Seven treatments by a laser therapist did not change the problem. As a result Beauty was left unused until April 1999.

VISIT 1. 23/4/99

Examination Beauty was difficult to handle and had a "bad attitude". She was very tender on palpation over the dorsal edge of the scapula and around the girth area behind the elbow. She would react to palpation by trying to turn and bite. The tenderness extended into the pectoral muscles in the region of the girth. This muscle, like that over the scapula, was tense. The sensitivity of the girth area was localised to the 4th intercostal space. There was minor tenderness over the saddle seat area and sacral apex.

Treatment Chiropractic adjustment of the costo-vertebral joints and vertebral motor units were performed using the dorsal spinous process of the 4th thoracic vertebra. It was adjusted from both the left and the right sides.

VISIT 2. 7/5/99

History Beauty had been much better but was still reacting to being girthed up. She was much less aggressive but still turned her head and went to bite, though was not very serious about her intent.

Examination Beauty’s attitude was much more compliant and much less protective of her girth area. Palpation and testing of the area behind the elbow revealed an 80% improvement in comfort. There was some tenderness again at the sacral apex.

Treatment The adjustment was performed as on the first visit. Beauty was then saddled. No resistance or reaction to saddling was noted.

VISIT 3. 16/7/99

History Beauty had been very good. She now only lifted her head slightly when being girthed up.

Examination Beauty was not at all tender over the left lower girth area and was only mild to moderately tender over the right lower girth area. Deep palpation of the 4th intercostal from the sternum up to the border of the scapula provoked a mild reaction.

Treatment Adjustment of the 4th thoracic vertebra as above.

Clinical outcome. Adjustment as above removed the residual sensitivity.

TREATMENT DETAIL.

The abnormal sensitivity if the girth area was removed or diminished by chiropractic adjustment of the costovertebral joints and secondary relaxation of knots or trigger points in the trapezius muscles.

Method;

PATIENT POSITION: Standing square. Assistant may stabilise patient by bracing on opposite side (face across, fencer stance, one hand on each of adjacent spinous processes).

DOCTOR POSITION: Partially elevated, on ipsilateral side of horse, face across. Fencer stance.

CONTACT POINT: Chiropractic "T-Bar or pisiform.

SEGMENTAL CONTACT POINT: Doral spinous process immediately under the tip.

LINE OF CORRECTION: Lateral to medial, slight dorsal to ventral (20 degrees above horizontal).

THRUST: Toggle recoil, fast and forceful. (Though this is a long lever move, the spinous process is very well stabilised by muscle and the scapulae. In my hands low force often does not clear the dysfunction completely, even with high speed).

Rationale behind approach: "Girthy" horses usually show tenderness which tracks along the back of the ribs involved. This location is consistent with the path of the intercostal nerves1. These nerves exit the spinal canal through the intervertebral foramen and course around the costovertebral joint during their passage down the rib1. The hypothesis behind the adjustment is that the associated vertebral motor unit and costovertebral joint are dysfunctional and that adjusting them resumes normal function of these joints, thus removing the disturbance of the nerve root and nerve as it courses from the spinal cord to the intercostal space. Supporting this hypothesis is that the focus of readily apparent abnormal sensitivity (in the region above and behind the elbow) can be traced back up one or more intercostal spaces. In addition to this the affected intercostal space is always associated with a vertebral motor unit that shows reduced rotation on motion palpation. Correcting the motion restriction of the vertebral motor units decreases the "girthy" symptoms by 30-50%. If the adjustment is taken further and deeper, to a point where we would expect to significantly affect the motion of the costo-vertebral joints, then we usually see a 50 to 95% decrease in the "girthy " symptoms from one chiropractic adjustment.

The resetting of the muscles, or relaxation of trigger points, in the region of the dorsal spinous process, and in particular the trapezius muscles, also appears to play a part in the reduction of the "girth" pain. It appears that these trigger points refer down into the girth region. This effect is supported by the fact that use of an "activator" on the trigger points in this muscle above the scapula usually eases the "girthiness" significantly2 (40-50% in most cases, in my experience). However, adjustment as above seems to give a consistently better and longer lasting result.

Acupuncture treatment, of Spleen 21a3 a point associated with the lateral thoracic nerve plexus, which in turn has communication the with the first few intercostal nerves, Small intestine 12 and 14 and trapezius trigger points, is also useful in reducing sensitivity and may help in reducing the chance of recurrence.

Discussion: "Girthiness" is a more commonly found in saddle horses but is also present in foals, harness and unbroken horses. Its aetiology is unclear. Tripping or falling with a saddle on has previously been mooted as a possible cause (via the resultant force of a fall, transmitted to the ribcage by the leg, against the non flexible band created by the saddle girth 4). Though such falls may exacerbate an underlying condition, having unbroken horses with this condition demands that we must look further for an aetiology. Recent research by Jean et al5 on thoracic trauma of foals may have pinpointed the inciting cause. In their paper is described the findings of the examination of 236 foals for thoracic rib cage trauma shortly after birth. Over 20% had rib cage asymmetry and 5% had rib fractures. This trauma was not apparent unless specifically looked for. Similarly Mee6 has reported a high incidence of rib fractures in neonatal and stillborn calves. The fractures usually occurred at the costochondral junctions of the cranial ribs. Most significantly the findings of both of these studies raise many questions as to the disruption to the cranial ribs, costovertebral, costochondral junctions and vertebral zygapophyseal joints at birth. Like the findings with intercostal nerve pain, the thoracic trauma in these studies was centred specifically around the cranial ribs. Could birth trauma be the source of girth pain that plagues a high proportion of horses through their lives?

Conclusion: Chiropractic adjustment, acupuncture and trigger point therapy can successfully treat a poorly recognised and poorly understood cause of pain, reduced performance and secondary behavioural problems associated with girth discomfort in horses.

Acknowledgments. The basis of this paper originates with the work of Dr Sharon Willoughby DVM DC and the American Veterinary Chiropractic Association. Based on the work of Dr Willoughby, the ACVA continually runs intensive and detailed chiropractic courses on animal chiropractic and spinal dysfunction management for veterinarians and chiropractors in the USA. The majority of this paper, however, is the result of clinical experience and personal research by the author. I thank Phil Rogers, Dublin, for help in editing this draft for the Web Journal of Acupuncture.

General References:

 

Specific References:

  1. Sisson and Grossman’s The Anatomy of the Domestic Animals 1975 Vol 1 Pages 266-270,401-405, 667-678.
  2. Dr Desmond Greaves D.C, Tutor, Royal Melbourne Institute of Technology University’s Master of Chiropractic (Animal Chiropractic) Course. Personal communication March 1999.
  3. Dr Marvin Cain. DVM Cert Vet Acupuncture(IVAS) Acupuncture in Animals, Post Graduate Committee in Veterinary Science Proceedings 167, 1991. Page 472.
  4. Dr Sue-Ann Lesser DVM Dip Vet Chiro. Past Lecturer AVCA. Personal communication June 1993.
  5. D.Jean, S.Laverty, J. Halley, d.Hannigan and R.Leveille. Thoracic trauma in newborn foals EVJ 1999 31 (2)149-152
  6. J.F.Mee(1993) Bovine Perinatal Trauma. Vet. Rec. 133,page 555

Copyright © Ian Bidstrup July 1999.