Prior to the mid-1970’s, the approach to equine orthopaedic problems was relatively unsophisticated. The veterinarian had few options for fixation of fractures, and some joint surgeries had been done through an open incision (arthrotomy). The two major advances in the modern era have been the development of sophisticated internal fixation techniques, and the development of techniques of arthroscopic surgery.

Improved ability to manage major fractures in the horse came with adoption of the Swiss AO (ASIF) system of internal fixation. Developments of strong screws and plates allowed the repair of many fractures, particularly in the distal limb. Techniques that are now routine include lag-screw fixation of slab fractures of the carpus, condylar fractures of the distal metacarpus and metatarsus fetlock joint, and fractures of the phalanges using compression screws. Plating techniques have been developed, and it is now possible to treat most electron fractures at any age, treat most long-bone fractures in young foals and selected long-bone fractures in older horses.

The arthroscope was used diagnostically in the 1970’s, and this allowed sophisticated appraisal of the entire joint, enabling an accurate diagnosis and, therefore, a better treatment plan. Starting in 1980, arthroscopic surgical techniques were developed, using triangulation principles, so that surgical removal of chip fragments, as well as lag-screw fixation of articular fractures and the treatment of osteochondritis dissecans (OCD), could be done with the arthroscope through one small portal and the instrument though another. This technique is now routine, but demands skill and experience. With the exception of major comminuted fractures involving the joint, all surgery is done arthroscopically now. The various conditions that can be treated with arthroscopy and the results of those treatments will be presented. Athletes can be returned to their original level of performance.

As surgery became more sophisticated, limitations in what could be returned to complete athletic activity was recognized. Most of the limitations revolve around the failure of articular cartilage to heal. Considerable research has gone into methods of articular cartilage resurfacing, and some of these most sophisticated methods are currently being used in the horse. It has also been recognized that early diagnosis is critical, and there have been major advances in the techniques of imaging, as well as synovial fluid and immunologic markers, to diagnose early change in the articular cartilage and bone. Early diagnosis of articular degradation is critical for the effective management of osteoarthritis, and early diagnosis of subchondral bone disease will potentially open the door to the prevention of fractures in the equine athlete.

To minimize the permanent damage we encounter at surgery, early diagnosis and early treatment become critical. Not all orthopaedic conditions are surgical. Newer imaging techniques and the use of synovial fluid in serum markers has vastly improved our early recognition of disease. In addition, novel techniques, such as gene therapy, are also being used to treat inflammatory arthritis in the horse; they will also be discussed.

The use of these modern-day orthopaedic techniques will be presented with examples from various clinical cases; a glimpse into the future where research is improving these techniques will also be covered.

References

1.  McIlwraith, C.W. Diagnostic and Surgical Arthroscopy in the Horse. 2^nd Edition. Lea and Febiger: 1990.

2.  McIlwraith, C.W. and Trotter, G.W. (Eds.). Joint Disease in the Horse. WB Saunders: 1996.

3.  Nixon, A. J. (Ed). Equine Fracture Repair. WB Saunders: 1996.