Many of you will have wondered if your horse is sore in the sacroiliac region (SI). How can you tell? In this study, the researchers looked at the symptoms seen in 296 horses which responded to nerve blocking the sacroiliac region, and therefore presumably had pain in that region, as well as horses whose SI region was flagged up on a bone scan. 43 of the horses had pain only in the SI region, the rest (253) had pain in the SI region and elsewhere as well. The horses with just SI pain had sore back muscles, reduced movement through the back, poor hindlimb impulsion, and were stiff in their ridden work. In their ridden work, over half struggled with the contact, over 80% had a worse canter than trot, and a third bucked or kicked out in canter. The symptoms were worse for both groups when the horse was ridden, compared to on the lunge.
Of the horses that responded to nerve block and also had a bone scan, the SI region showed up as a concern on the bone scan in only 43%. Ultrasound examination of the SI region showed abnormalities in just 32%. This shows that whilst ultrasound and bone scan can help to diagnose SI joint region pain, a lack of findings on bone scan or ultrasound does not necessarily mean that there is not pain in that region.
Barstow, Amy & Dyson, Sue. (2015). Clinical features and diagnosis of sacroiliac joint region pain in 296 horses: 2004–2014. Equine Veterinary Education. 27. 10.1111/eve.12377.
You can access the full article here.
There has been no large-scale study of the clinical signs of sacroiliac (SI) joint region pain and its association with lameness and/or thoracolumbar pain. Horses with a positive response to infiltration of local anaesthetic solution around the SI joint regions (SI block) and/or abnormal radiopharmaceutical uptake (RU) in the region of the SI joints were included. History, clinical signs, diagnostic imaging findings, response to SI block, and concurrent lameness and/or thoracolumbar pain were recorded. Horses (n = 296) were divided into 2 groups: SI joint region pain only (Group 1, n = 43) and SI joint region pain and concurrent source(s) of pain (Group 2, n = 253). Clinical signs in Group 1 included increased tension in the longissimus dorsi muscles (40%), restricted flexibility of the thoracolumbar region (44%), trunk stiffness during exercise (61%) and poor hindlimb impulsion (56%). When ridden 65% had a poor contact with the bit, in 81% canter quality was worse than trot, and 35% bucked or kicked out with a hindlimb during canter. In both Groups 1 and 2 clinical signs were seen in a significantly greater proportion of horses during ridden work than lungeing (P<0.0001). Following SI block, 98% of horses showed dramatic improvement in clinical signs, including greater overall movement through the trunk, increased hindlimb impulsion and better quality canter. Abnormal RU in the SI joint regions was seen in 85/180 (47%) horses. Of horses with a positive response to SI block that underwent scintigraphy, only 43% had abnormal RU. Per rectum ultrasonographic examination of the SI joint region revealed abnormalities in 41/129 (32%) horses. Clinical signs of SI joint region pain are worse when horses are ridden. Sacroiliac joint region diagnostic analgesia is a useful, safe but nonspecific block. Ultrasonography and scintigraphy can provide additional information in some horses, but negative results do not preclude SI joint region pain.
Dr Sue Dyson and I are in the process of writing a book for horse owners and riders on how to understand and use the Ridden Horse Pain Ethogram with your own horse. The book will be published by J A Allen, and available sometime In 2023. Sign up to my newsletter at www.thehorsephysio.co.uk for updates.
In the meantime, you can learn more about the Ridden Horse Pain Ethogram through listening to Dr Sue Dyson explaining here it on the Equine Veterinary Education, where you can also listen to her discussing many of the other studies that she has been involved in. You can also take an online course with Equitopia.
© Sue Palmer, The Horse Physio 2021
Treating your horse with care, connection, curiosity and compassion
