Fractures of the third trochanter in horses: 8 cases (2000-2012).

This study investigates the features, management, and outcomes of third trochanter fractures in horses, using data from eight cases between 2000 to 2012. It found that these fractures are associated with severe lameness but can be successfully managed non-surgically, and horses can return to sporting activities after a period of rest.

Study Objectives and Methods

• The aim of this retrospective case series study was to identify the characteristics, management practices, and outcomes of third trochanter fractures in horses.
• The study analysed data of eight horses from records between 2000 to 2012.
• Data included signalment, case history, severity and duration of lameness, physical and lameness examinations, imaging findings, management, and outcome.

Key Findings

• Every horse in the study had experienced an acute onset of severe lameness.
• Physical signs of fracture were present in half of the horses.
• Ultrasonography identified single displaced bony fragments in seven out of eight horses, and multiple bony fragments in one horse.
• Concurrent enthesopathy in the gluteus superficialis muscle was found in seven horses.
• A specific radiographic view obtained in three horses revealed a simple complete longitudinal fracture between the mid-level and the base of the third trochanter.
• Nuclear scintigraphy was used in two horses to locate the affected limb area for further examination.
• Follow-ups showed that fractures had healed with a fibrous union, though cranial displacement of the fragment persisted.
• All horses’ lameness was resolved after non-surgical management.

Conclusions

• The results suggest that a third trochanter fracture should be considered a possible cause of hind limb lameness in horses, particularly if the proximal part of the limb is impacted.
• Ultrasonography was highlighted as an effective diagnostic tool, with nuclear scintigraphy also being useful in identifying the affected area.
• The research confirmed a good prognosis for horses with a third trochanter fracture, with complete recovery possible following a period of rest and restricted exercise.