Review of injection techniques targeting the sacroiliac region in horses

Abstract

Summary Local anaesthetic techniques and diagnostic imaging tools are currently used in conjunction with thorough physical and lameness examinations to diagnose sacroiliac disease (SID) in the horse. The deep and inaccessible location of the sacroiliac joint (SIJ), however, often renders diagnostic imaging modalities, such as radiography, nuclear scintigraphy and ultrasonography, unreliable in identifying sacroiliac problems. The equine clinician therefore often has to rely on positive results of local anaesthetic techniques to confirm a diagnosis of SID. Regional infiltration techniques have been described but result in a diffuse distribution of large volumes of local anaesthetic solution throughout the entire lumbosacroiliac region, which is nonspecific to the SIJ and has the potential to produce false positive results. Several periarticular injection approaches to the SIJ have recently been described. A combination of periarticular SIJ injections with the use of modest amounts of local anaesthetic solution provides increased SIJ specificity, but may lead to false negative results in cases where the pain originates from surrounding soft tissues. This article clarifies terminology related to sacroiliac injections, reviews current injection techniques, highlights the advantages and disadvantages of each approach, and investigates injectate volume considerations.

Evaluation of the diagnostic accuracy of skeletal scintigraphy in lame and poorly performing sports horses

“…Diagnostic analgesia can confirm the presence of pain in the sacroiliac joint region . However, this is a nonspecific block and there is potential for local anesthetic solution to diffuse around the dorsal sacroiliac ligaments and the lumbosacral joints . There are likely to be several different pathological processes that can cause pain in the sacroiliac joint region, which may explain the observation of moderate sensitivity and specificity of increased radiopharmaceutical uptake for final diagnosis.…”

“…33 However, this is a nonspecific block and there is potential for local anesthetic solution to diffuse around the dorsal sacroiliac ligaments and the lumbosacral joints. 47,[56][57][58] There are likely to be several different pathological processes that can cause pain in the sacroiliac joint region, which may explain the observation of moderate sensitivity and specificity of increased radiopharmaceuti-cal uptake for final diagnosis. In a recent study of horses with sacroiliac joint region pain (as confirmed by a positive response to infiltration of local anesthetic solution around the sacroiliac joint regions), only 72/167 (43%) had increased radiopharmaceutical uptake.…”

Clinical features and diagnosis of sacroiliac joint region pain in 296 horses: 2004–2014

“…). Ultrasound‐guided injection of the SI joint region has been described (Denoix and Jacquet ); however, the cranial approach is effectively blind once the needle has passed under the ilial wing and the caudal approach risks damage to neurovascular structures (Engeli and Haussler , ) and sciatic nerve paralysis. The dramatic clinical improvements following SI block demonstrate the high level of discomfort experienced by many horses with SI joint region pain.…”

“…However, it is recognised that this analgesic technique is not specific for the SI joints, and can influence closely related anatomical structures (Dyson and Murray ; Engeli et al . ; Engeli and Haussler ).…”

“…Seventythree (99%) horses had abnormal radiopharmaceutical uptake (RU) in the SI joint region and 34/34 (100%) horses had a positive response to infiltration of local anaesthetic solution around the SI joint regions. However, it is recognised that this analgesic technique is not specific for the SI joints, and can influence closely related anatomical structures Engeli and Haussler 2012).…”