Introduction

• Cause: trauma during handling, falling or dropping from a height, trapping of feet or limbs in wire cages.
• Signs: lameness (acute or chronic), joint effusion and swelling (this might be difficult to appreciate in small patients, pain and/or vocalization upon palpation or upon mobility, refusing to weight bear and move, lethargy, inappetence.
• Diagnosis: clinical signs, clinical exam, palpation findings (joint instability), diagnostic imaging (radiography, computed tomography).
• Treatment: reduction of subluxation or luxation (closed or open). External coaptation, analgesia and rest may be suitable in some cases of subluxation or luxation. In some cases of luxation, amputation or internal/external fixation (with or without external bandage) may be required.
• Prognosis: guarded to good.

Pathogenesis

Etiology

• Traumatic.
• Secondary to concurrent disease, eg metabolic bone disease.
• Idiopathic.

Predisposing factors

General

• Inappropriate husbandry leading to injury, eg wire floor cages, slippery floors.
• Conformation, eg underlying osteoarthritis.
• Underlying disease, eg metabolic bone disease.

Specific

• Traumatic event.

Pathophysiology

• Traumatic (most common).

Timecourse

• Acute: majority of cases.
• Chronic: outdoor animals monitored less closely.

Diagnosis

Treatment

Prevention

Outcomes