Modified technique for resection of the alar folds to nasal paralysis in a mule: Case report.

Overview

• This case report details a modified surgical technique to treat nasal paralysis in a mule, a condition that causes nasal collapse due to facial nerve injury.
• The procedure involved resection of the alar cartilage to restore airway patency and alleviate respiratory distress, with successful long-term outcomes.

Background

• Equids, including horses and mules, rely exclusively on nasal breathing, making any nasal obstruction a serious issue that can impair breathing and athletic ability.
• Nasal paralysis occurs due to injury of the facial nerve or its branches, which normally control movement of the alar cartilage in the nose.
• When paralysis occurs, the alar cartilage ceases to move, leading to collapse and blockage of the nasal passage.
• This condition is rare in horses and previously undocumented in mules, underscoring the uniqueness of the reported case.

Case Description

• The subject was a 9-month-old mule that had suffered facial trauma and compression from a halter, which likely caused injury to the facial nerve.
• Initial treatment involved anti-inflammatory drugs and temporary retention sutures to address nasal collapse, but these were ineffective.
• Given the failure of conservative approaches, a surgical intervention was chosen to correct the collapsed nasal structure.

Surgical Technique

• The mule was placed under general anesthesia and positioned in sternal recumbency (lying on the chest).
• To access the affected area, traction was applied to the apex (tip) of the alar cartilage lamina to lift it and facilitate the surgical incision.
• An elliptical skin incision was made over the alar cartilage to expose it.
• The alar cartilage was then resected (surgically removed) to prevent collapse and restore airway patency.
• The skin was closed using a simple continuous suture pattern, which promotes good wound healing and minimizes additional tissue trauma.

Outcomes

• The mule recovered satisfactorily from surgery, with no immediate complications observed.
• Airway patency—the openness of the nasal passages—was maintained postoperatively, allowing proper nasal breathing.
• Two months following surgery, the mule showed stable health with no signs of nasal collapse, indicating a successful long-term outcome.

Significance and Implications

• This case highlights the importance of exploring surgical options when conservative treatments fail to resolve nasal paralysis and collapse.
• The modified surgical approach provides a viable alternative to restore function in cases of alar cartilage paralysis, especially in mules whose cases are previously unreported.
• Efficient correction of nasal collapse can improve animal welfare by relieving respiratory distress and supporting athletic capabilities.
• The report encourages further investigation into surgical techniques tailored to treat nasal paralysis in equids and contributes valuable clinical knowledge for veterinarians managing similar cases.