Mathematical modelling of bone adaptation of the metacarpal subchondral bone in racehorses.

This research study investigates the adaptation of subchondral bone in racehorses’ metacarpal regions to repetitive loading conditions, such as those experienced during training. By creating a mathematical model based on observed in vivo data, the researchers aim to better understand how changes in training strategy can potentially reduce the risk of injury in racehorses.

Understanding the Purpose of the Research and Methodology Used

• The main purpose of the study was to understand how subchondral bone – the layer of bone just under the cartilage in a joint, in the metacarpal region of racehorses adapts to repetitive loading and training. This understanding could help reduce the risk of injuries in racehorses during their training.
• To do this, the researchers developed a mathematical model using a square root function that represents the relationship between the bone volume fraction (BVF) and the specific surface (BS) of the subchondral bone.
• This relationship was determined from the lateral condyles of the third metacarpal bone (MCIII), a key area of the horse’s limb that often experiences a high degree of stress and is prone to injury.

The Mathematical Model and Its Variables

• The mathematical model they created is an ordinary differential equation that incorporates a formation rate dependent on strain energy density, an indication of the energy stored in the bone due to deformation caused by applied loads.
• When applied to a selected subchondral region (or volume of interest), the model estimates the strain the subchondral bone is under based on the joint contact forces imposed on the horse during training.
• For each of the initial conditions of BVF, the research indicates that the subsequent homoeostatic BVF at any given loading condition is similar, but the time to reach equilibrium varies depending on the initial BVF and loading condition.

Evaluation of the Model and Implications of Findings

• The developed mathematical model produced calculated BVF values that were a good approximation to existing data from racehorses, whether in training or at rest.
• This suggests that the model may be effective in predicting how the subchondral bone in the horse’s metacarpal regions adapts to varying loading conditions.
• Overall, the research provides a basis for better understanding how changes in training strategies may affect the health and endurance of racehorse bones, with the ultimate goal of reducing the potential for fractures and injuries.