A technique for laser-facilitated equine pastern arthrodesis using parallel screws inserted in lag fashion.

This study investigates a new technique for minimally invasive equine pastern (interphalangeal joint) arthrodesis, or joint fusion, involving lasers and parallel screws. The technique appeared cost-effective and less painful compared to conventional methods, offering a promising alternative for horses with advanced osteoarthritis of the pastern.

Research Methodology

• The research involved six horses in total, with five thoracic and two pelvic limbs undergoing the pastern arthrodesis (PIJ).
• Diagnosis of the interphalangeal joint osteoarthritis (OA) was solidified through radiography for all subjects.
• A diode laser was then used to apply 2000 J of energy to the affected joint.
• Subsequently, three parallel 5.5 mm screws were inserted in a specific method known as ‘lag fashion,’ through minor incisions, to achieve joint fusion.
• Post-anesthesia, the treated limbs were either bandaged or put in bandage casts for a duration of three weeks.

Results of the Study

• The horses were monitored throughout the follow-up period which lasted between 6 to 18 months.
• Four limbs of three horses were sound or without issues throughout the follow-up duration.
• Various degrees of lameness were observed in the remaining horses; one remained lame in the 1st month, another displayed mild lameness at 6 weeks, and another showcased low-grade persistent lameness along with delayed joint fusion after a year.
• Within six months, five horses were sound again, four showed radiographic evidence of successful joint fusion, and five had returned to their intended uses.

Conclusion of the Study

• The use of a diode laser along with the insertion of three parallel screws in lag fashion for PIJ osteoarthritis is less costly and associates with less pain compared to the standard open PIJ arthrodesis technique.
• In horses with advanced PIJ osteoarthritis, this new method could present a viable alternative for PIJ arthrodesis.
• The researchers recommend further exploration of this technique, including understanding the effects of the laser, ideal case-selection indications, and optimal laser dosage, before it can be recommended for standard PIJ arthrodesis procedures.