34th Annual Scientific Meeting proceedings

Objectives:

Non-septic tenosynovitis (NST) of the DFTS is common in horses. This is most commonly associated with damage of intrathecal structures such as the MF, DDFT and SDFT. In rare instances, PSB fractures have been reported to cause DFTS pathology. However, to the best of the author’s knowledge, treatment and outcome of such cases has not been reported.

Methods:

A 7-year-old Warmblood mare presented 3/5 (AAEP) RH lame and with effusion of the DFTS. The horse had a field accident 9 weeks earlier and presented with marked response to fetlock flexion and digital palpation of the abaxial border of the lateral PSB. Radiographic examination of the RH fetlock revealed a non-articular abaxial, displaced lateral PSB fracture. Ultrasonographic examination revealed moderate effusion of the DFTS with no concurrent intrathecal pathology. Due to the lack of improvement with conservative management, DFTS tenoscopy was performed.

Results:

During tenoscopy, a transverse tear of the DFTS wall at the level of the abaxial margin of the lateral PSB at the junction between the PAL and proximal scutum was identified. Probing through the tear led to the PSB fracture. A combination of ultrasonographic and radiographic guidance was used to facilitate tenoscopic portal creation for fragment removal. After 5 months of rehabilitation the mare returned to the previous level of activity.

Conclusions:

Although rare, abaxial fractures of the PSBs should be included in the differential diagnosis of NST in horses. In cases where conservative management does not resolve the lameness, fragment removal under tenoscopic guidance can be curative.