Scapulohumeral osteochondrosis. A retrospective study of 32 horses.

The research article focuses on a retrospective study of 32 horses with a condition known as shoulder osteochondrosis (OC), exploring the outcomes after they received either surgical or conservative treatment. A critical finding from the study was that the general prognosis for shoulder osteochondrosis in young horses is poor and is influenced partly by the horse’s breed and intended use.

Background and Methodology

• The objective of the study was to retrospectively examine the outcome of horses suffering from shoulder osteochondrosis (OC), a joint condition that was treated either through surgery or non-invasive methods.
• The study involved 32 horses aged less than two years diagnosed with OC affecting the scapulohumeral joint (SHJ), one of the main shoulder joints in horses.
• Lesion severity was determined using measurements from lateromedial radiographs, producing images of the shoulder joint from different angles.
• Data for assessing the outcome was obtained from horse racing records or through telephone interviews with horse owners. A successful outcome was defined as the horse’s ability to perform its intended use.

Results

• The study found that out of the 32 horses, 16 were bilaterally affected (both shoulders were affected, meaning 48 joints in total).
• Of the horses with bilateral OC, 11 underwent arthroscopic surgery, a minimally invasive surgical procedure on a joint. Five of these underwent bilateral arthroscopy, and six underwent unilateral arthroscopy for the most severely affected joint.
• Eight horses with unilateral OC were treated with arthroscopy.
• The overall outcome was poor. Only 15.4% of racing horses (4 out of 26) were able to commence a race, and 67% (4 out of 6) of non-racing horses were deemed ‘sound’ for their intended use.
• The breed of the horse showed a statistically significant difference in treatment outcomes. However, there was no significant relationship between outcome and other variables such as gender, affected limb, whether one or both shoulders were affected, treatment type, or severity of the radiographic lesion.
• However, the study found a significant positive correlation between the severity of the radiographic lesion on the humerus (bone of the upper limb) and glenoid (part of the shoulder joint).

Conclusions

• The study concluded that the prognosis for shoulder OC in young horses is generally poor.
• The outcome appears to depend, to some extent, on the breed of the horse and its intended use.
• It was also concluded from the study that there was no difference in treatment outcomes between horses treated surgically and those treated conservatively.