Alternative Ultrasound-Guided Approach to the Coxofemoral Joint in Horses With Severe Coxofemoral Pathology

Cranioventral distention occurs in horses with severe chronic coxofemoral injury. Ultrasound-guided access to this recess provides an alternative approach in affected horses that may benefit from diagnostic or therapeutic injections. 

1. Introduction

Intra-synovial access to the coxofemoral joint is notoriously challenging. Blind injections rely upon inconsistently palpable landmarks, and ultrasoundguidance requires expertise for accurate needle placement. Aspiration of synovial fluid is recommended to avoid sciatic nerve anesthesia but is inconsistent. Cranioventral synovial distention in horses with coxofemoral disease may provide an alternative injection site.

2. Materials and Methods

Horses with cranioventral distention identified during pelvic ultrasonography from 2009 to 2014 were considered for injection. The cranioventral recess was identified adjacent to the proximal femur and ventral to the cranial joint margins with a low-frequency transducer. Using aseptic technique, spinal needles were placed cranial to the transducer and advanced caudomedially into the recess.

3. Results

Nine injections were performed in six horses for therapeutic (n = 6), diagnostic (n = 1), and post-mortem (n = 2) validation purposes. Except for one foal, all were aged horses (15–29 y) with prominent lameness due to subluxation (n = 3), luxation (n = 2), or osteoarthrosis (n = 1). Synovial fluid was retrieved in all cases with one needle placement. Another seven horses had cranioventral distention but were not injected or underwent ultrasound-guided injection using dorsal approaches. All but one had severe coxofemoral pathology.

4. Discussion

When distended, ultrasound-guided access to the cranioventral recess is straightforward and may reduce extra-synovial placement of injectants. Distention is often accompanied by severe pathology that may respond to therapeutic injections.

Acknowledgments

Declaration of Ethics

The Authors declare that they have adhered to the Principles of Veterinary Medical Ethics of the AVMA.

Conflict of Interest

The Authors declare no conflicts of interest.