Median Sternotomy Closure Using an Ultra-High-Molecular-Weight Polyethylene Suture Following Thymectomy in a Dog: A Case Report.

A 10-year-old castrated male Chihuahua weighing 3.06 kg was presented with a chronic, progressively worsening cough of five months' duration. Diagnostic imaging, including thoracic radiography and computed tomography, identified a well-defined cranial mediastinal mass consistent with a thymic tumor. Surgical excision was performed via median sternotomy with complete thymectomy. Following tumor removal, sternal closure was achieved using a non-absorbable ultra-high-molecular-weight polyethylene (UHMWPE) suture material (FiberWire®, Arthrex, Naples, FL, USA). Histopathological examination confirmed the diagnosis of an epithelial-predominant thymoma with narrow but complete surgical margins. Postoperative recovery was uneventful, and the dog was discharged three days after surgery. Clinical signs, including coughing, progressively improved during follow-up. Radiographic evaluation performed up to postoperative day 57 demonstrated stable sternal alignment without evidence of dehiscence, implant-related complications, or disease recurrence. This report describes the first clinical case of FiberWire use for median sternotomy closure following thymectomy in a dog. The favorable clinical and radiographic outcomes observed during postoperative follow-up suggest that FiberWire may represent a viable alternative to traditional stainless-steel wire for sternal fixation in canine thoracic surgery.