The effect of manually facilitated flexion of the thoracic spine on the interspinous space among horses with impinging dorsal spinous processes of the thoracic vertebrae.
Authors: O'Sullivan S, McGowan C M, Junnila J, Hyytiäinen H K
Journal: Veterinary journal (London, England : 1997)
Summary
# Editorial Summary Impinging dorsal spinous processes (IDSP) represent a common diagnosis in ridden horses, yet standard radiographic assessment may not account for how posture influences the spacing between affected vertebrae—a potential limitation when determining treatment necessity. O'Sullivan and colleagues investigated whether a manual facilitation technique ('thoracic lift') to encourage thoracic flexion could alter interspinous space distances in seven horses with confirmed thoracic IDSP, comparing radiographs taken in the horses' spontaneous posture against those obtained during facilitated flexion, with blinded measurements analysed using Hodges-Lehmann median differences. Remarkably, interspinous spacing increased at every measured thoracic level (T5–T18), with the most substantial gains of 3.1 mm and 3.0 mm respectively at the T7–T8 and T12–T13 spaces, whilst the caudal thoracic region showed more modest improvements of 0.7 mm at T17–T18. These findings carry significant implications for clinical practice: posture-dependent changes of this magnitude could meaningfully alter radiographic IDSP grading and potentially influence decisions about farriery modifications, exercise restriction, or therapeutic intervention—suggesting that dynamic assessment and postural correction strategies warrant consideration alongside static imaging in horses presenting with dorsal spinous process pathology.
Read the full abstract on PubMed
Practical Takeaways
- •Radiographic diagnosis and grading of IDSP should account for thoracic posture, as facilitated flexion can increase interspinous spaces by up to 3.1 mm and may affect severity assessment
- •Manual thoracic lift techniques can temporarily increase interspinous spacing in horses with IDSP, which may have therapeutic or diagnostic implications for clinical management
- •Single radiographs in spontaneous posture may overestimate the severity of IDSP; consider repeat imaging in flexed postures for more complete clinical assessment
Key Findings
- •Manual facilitation of thoracic flexion increased interspinous space distances at all thoracic intervertebral spaces (T5-T18) in horses with IDSP
- •Greatest median increases in interspinous space were 3.1 mm at T7-T8 and 3.0 mm at T12-T13
- •Smallest median increase was 0.7 mm at T17-T18
- •Posture significantly affects interspinous space measurements and could influence IDSP grading and clinical decision-making