Sticks in the Coronary Band

Surgeons from a private equine clinic in Central Virginia used 20 years of medical records to identify and review 15 cases of horses with a wooden foreign body penetrating the coronary band.

Owners most reported the horses had either fallen or were jumping while foxhunting in wooded areas with the lameness usually presenting immediately after the injury. Owners or primary care providers had attempted removal of the foreign body in about half the cases before referral.

Most (93%) of the horses were Grade 4/5 lame at a walk-on presentation and had soft tissue swelling at the coronary band and increased digital pulses in the affected feet. The front feet were most affected in the toe area. While about half of the foreign bodies were visible, seven were not visible and in five of these cases, external portions of the stob reportedly broke off during those attempts. No synovial structures were involved in any of the cases. 

Removal was eventually achieved using standing sedation and nerve blocks of the distal limb in 80% of the cases with three requiring general anesthesia. A limited hoof wall resection was done in nine horses to facilitate the removal of stobs broken off at or below the coronary band. Following the superficial hoof wall resection, the stobs were removed through proximal traction and a gentle rocking motion facilitated by taking pressure off the foreign body, so it was no longer squeezed between the hoof wall and the coffin bone. The feet were bandaged and poulticed following removal, and all horses received systemic antibiotics and anti-inflammatory medications for several days. Most (87%) of the horses were sound at a walk within 24 hours, all walked sound at 2 weeks and all returned to their previous levels of work after 8-10 weeks.

— Trostle SS et al. JAVMA 2024;262:1099-1103

Gene Therapy for Arthritis

Researchers from Colorado State University successfully used gene transfer technology to inhibit the inflammatory protein interleukin-1 beta (IL-1ß) in joints with experimentally induced traumatic arthritis.

The treatment was injected into arthritic joints to genetically modify synovial and cartilage cells to increase the production of an antagonist to IL-1ß resulting in decreased pain and lameness as well as improved joint health in the face of traumatic arthritis.

Sixteen clinically normal horses were used in the study with the experimental treatment randomly applied to one affected carpal (knee) joint on half the horses. In contrast, other horses and joints served as controls. Over 70 days, they observed improved lameness scores (a significant one-point decrease on the 0-5 scale), suppression of inflammatory mediators in the joint fluid and microscopic improvements of articular cartilage and subchondral bone. The authors concluded that further evaluation of this gene therapy is warranted to optimize it as a treatment for arthritis in the horse.

— Goodrich LR et al. JAVMA 2024;262:S109-S120

Accelerometers Predict Risk of Racing Injury

Washington State University researchers used inertial measurement unit (IMU) sensors to identify Thoroughbred racehorses at increased risk for potentially catastrophic injuries while racing or breezing.

Each sensor, carried in a small pocket on the saddle pad, included three accelerometers that measured dorsoventral, longitudinal and mediolateral movement data at racing speeds. The sensors produced over 2,000 stride data points per second that were then filtered to reduce noise, averaged to summarize a typical stride for each horse and analyzed with an algorithm. The algorithm compares the data describing limb and torso movements of the test subjects with those of 37 graded stakes-winning horses considered to have ideal stride characteristics, then calculates the risk status of each horse on a scale from 1 (baseline risk) to 5 (horses 950 times more likely to sustain a catastrophic injury).

This report highlighted the results from one horse classified as having a risk factor assignment of 5 and two others that started at a risk factor of 3, then progressed to 5 over subsequent high-speed works or races, indicating a deterioration in stride characteristics. Upon veterinary examinations that included positron emission tomography (PET) scans, all three horses were determined to have lesions typical of horses that sustain condylar fractures. One horse also had a significant uptake pattern in a third carpal (knee) bone suggesting it was at increased risk for a slab fracture.

After rest, all three horses returned to racing or training with normal risk profiles. Acknowledging that three authors have a commercial interest in this StrideSAFE technology, this report still represents an exciting application of biometric sensors in equine practice that could help reduce the rate of catastrophic injury in racehorses.

— Mc Sweeney D et al. JAVMA 24.02.0114

New Self-Help Treatment for Arthritis

Scientists from New Bolton Center at the University of Pennsylvania investigated the efficacy of a new autologous protein solution (APS) for the intra-articular treatment of synovitis as a first-stage intervention to prevent arthritis.

APS was prepared by harvesting 55cc of blood from an individual, then processing this to concentrate platelets. This treatment was then administered intra-articularly to the hock joints of 12 horses with experimentally induced synovitis, while the controls were injected with saline for comparison.

Unfortunately, the APS treatment did not decrease lameness, joint swelling or synovial fluid parameters related to inflammation compared with the sham-treated controls. However, there were some positive gross and microscopic effects of the APS treatment on the cartilage and synovial membranes of treated joints.

— Usimaki A et al. EVJ 2024:14203