Quantitative Bone Scintigraphic Follow-Up After a 2-Month Cross-Training Program Including Swimming in Showjumping Horses with Back and Neck Pain.

Overview

• This study assessed changes in bone activity using scintigraphy in showjumping horses with back and neck pain during a two-month training program that combined swimming and ridden exercise.
• The goal was to understand how this cross-training affected skeletal lesions as measured by radiopharmaceutical uptake in different regions of the skeleton.

Background and Purpose

• Showjumping horses often suffer from neck and back pain related to vertebral lesions, which can affect their performance and wellbeing.
• Bone scintigraphy (a nuclear imaging technique) can highlight areas of increased bone metabolism or inflammation by measuring radiopharmaceutical uptake, helping to identify skeletal lesions.
• Swimming has been proposed as a low-impact exercise that might reduce axial (spine-related) musculoskeletal issues by allowing exercise without loading the spine.
• The study aimed to quantitatively evaluate changes in bone activity in horses undergoing a training program that included swimming, to see if this might influence bone metabolism in affected areas.

Study Design and Methods

• Participants: 18 showjumping horses with documented vertebral lesions causing neck and back pain were included prospectively.
• Training Program:
  • First 4 weeks: Conventional ridden work.
  • Next 8 weeks: Combination of swimming sessions and ridden exercise (cross-training).
• Imaging and Data Collection:
  • Bone scintigraphy was performed twice: at week 4 (after ridden work) and week 12 (after swimming plus ridden work).
  • Radiopharmaceutical uptake was measured in 205 predefined regions of interest (ROIs) across the skeleton.
  • Uptake values were normalized using a Z-score approach for standardization across horses and time points.
• Statistical Analysis:
  • A linear mixed-effects model was used for each ROI to assess the effect of time (week 4 vs. week 12) on normalized uptake, accounting for individual horse variability as a random effect.

Key Findings

• Overall changes in radiopharmaceutical uptake between week 4 and week 12 were minimal across all ROIs (average change near zero, ranging between -0.28 to 0.24 in Z-score units).
• Significant changes were detected in 21 ROIs:
  • 13 ROIs in the axial skeleton showed decreased uptake, suggesting reduced bone metabolic activity or inflammation in spinal regions.
  • 8 ROIs in the limbs, especially the humeral tubercles (shoulder area), showed increased uptake, indicating increased bone activity possibly linked to altered loading or exercise adaptation in these areas.
• There was notable variability between individual horses in scintigraphic changes, indicating different responses to the training program.

Interpretation and Implications

• The lack of increased radiopharmaceutical uptake in axial skeleton suggests that the training program including swimming did not exacerbate spinal bone lesions over two months.
• The decreased axial uptake might reflect some improvement or stabilization in vertebral bone metabolism, although this was modest and variable among horses.
• Increased uptake in limb regions could indicate compensatory adaptations or increased loading related to swimming and ridden work.
• Previous studies in this cohort had not shown clear changes in thoracolumbar mobility, so imaging changes might be more sensitive indicators of skeletal response than clinical mobility assessment alone.
• Results are preliminary and require controlled studies to:
  • Confirm the observed scintigraphic patterns.
  • Better elucidate how swimming and cross-training influence axial musculoskeletal health.
  • Guide optimal rehabilitation protocols for horses with back and neck pain.

Conclusion

• This study provides initial quantitative scintigraphic evidence that a cross-training program including swimming does not worsen and may modestly reduce bone metabolic activity in the axial skeleton of showjumping horses with back and neck pain.
• Simultaneously, it highlights increased bone activity in certain limb areas likely related to altered exercise mechanics.
• The findings emphasize the potential benefits and complexities of incorporating swimming into rehabilitation, but also the need for further research to optimize protocols and outcomes.