Critical Review of the Evidence Supporting Physiotherapeutic Management of Equine Sacroiliac Regional Pain Wareham, N., Hutson, P. and Tabor, G. (Hartpury University, Gloucester, GL19 3BE) Introduction
Background
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ERSP is associated with causing poor performance, most commonly presenting with reduced hindlimb engagement, reduced willingness to move forwards into a contact and a poor quality canter (Dyson and Murray, 2003). ERSP can also be a result of referred pain from pathology affecting the thoracolumbar spine and hindlimb, which share complex neurophysiological pathways with the sacroiliac joint (SIJ) region (Van de Wurff et al., 2006) further supporting collaboration with the veterinarian to establish correct diagnosis.
quine regional sacroiliac pain (ERSP) encompasses a wide variety of symptoms and is a recognised cause of hindlimb lameness and poor performance (Dyson and Murray, 2003). ERSP is more commonly recognised in performance horses; in particular those competing in dressage and show jumping sports (Dyson and Murray, 2003). The veterinary approach to managing ERSP aims to identify the underlying pathological process, followed typically by medical intervention; an imperative step in the veterinary physiotherapist referral pathway (Goff et al., 2008). Physiotherapy intervention utilises a range of assessment and treatment techniques, which act to identify and treat sensory and motor disturbances; restoring function, relieving pain and thus improving performance and quality of life (McGowen et al,. 2007). Current literature supports therapeutic exercise as an effective means of treating and managing ERSP (Clayton, 2012; Denoix and Jacquet, 2008; Goff et al., 2008; HeuftDorenbosch et al., 2006; McGowen et al., 2007; Stubbs et al,. 2011).
The kinematic importance of the SIJ is to provide a stable means of transferring force from the hindlimb to the thoracolumbar spine via the surrounding musculoligamentous system (Bronlinson et al., 2003). Notably, Degruence et al., (2004) assessed equine SIJ movement in vitro reporting less than 1 degree of translation. Goff et al., (2008) use the term ‘functional instability’ to describe reduced postural control around the SIJ rather than a true joint instability; reported in human literature as subluxation often secondary to catastrophic trauma or pathology (Bronlinson et al., 2003). Functional
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instability has been noted to cause a mild increase in articular translation which may result in SIJ remodelling and ERSP if not addressed (Bronlinson, 2003; Goff et al., 2008). Such functional instability affords the potential for physiotherapy intervention to assess and treat muscular imbalance and postural disturbances (McGowen et al., 2007) therefore supporting long term reduction in ERSP and promoting improved performance. ERSP secondary to SIJ dysfunction has been classified into two groups (Dyson and Murray, 2003; Goff et al., 2008); the first presenting with insidious onset of poor performance, responsive to local analgesia and the second, a more chronic picture encompassing poor performance and osseous, pathological SIJ change. Goff’s concept of functional instability is further supported by human research that suggests that it is the shearing and abnormal force closure of the joint that causes pain secondary to reduced postural control by the surrounding muscles (Hossain and Nokes, 2005; Snijders et al., 1998). It is proposed by Snijders et al., (1998) that the shearing forces are caused by the longitudinal muscles and that protection from this is sought from transversely aligned musculature such
