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A two-year-old, male-neutered German shorthaired pointer initially presented to the Animal Referral Hospital Canberra’s emergency department for assessment and investigation of severe trauma to the left proximal hindlimb and inguinal region. The patient had sustained this injury from an unprovoked dog attack while being walked.
Upon arrival the patient was found to be quite stressed, with elevated cardiac and respiratory parameters (heart rate 160, respiratory effort increased—although with no abdominal component, respiratory rate panting). A Glasgow Composite Measure Pain Scale (Short-Form) of 8/24 was given, and as such rescue analgesia administered (methadone 0.3 mg/kg and ketamine 1 mg/kg intravenous (IV)). In addition, the patient was started on Hartmann’s solution intravenously and held overnight for assessment by the referral surgical team the next day.
The patient’s initial bloodwork, including biochemistry, was largely unremarkable. Mild dehydration was noted and corrected with the intravenous fluid therapy.
Interventions
The patient was premedicated with medetomidine 3 mcg/kg, methadone 0.3 mg/kg and ketamine 0.5 mg/kg IV; then induced with alfaxalone 1 mg/kg IV and maintained on isoflurane and oxygen volatile. In addition, maropitant citrate 1 mg/kg IV was given. Once the patient was in lateral recumbency, preparation and examination of the injury could occur. The peri-wound region was clipped and sterilised with chlorhexidine tincture and copiously flushed with sodium chloride 0.9% solution. An entry culture-swab of the wound was also obtained.
The injury was found to be quite extensive, involving a full thickness laceration beginning cranially at the level of the greater trochanter, extending to the level of the tibial tuberosity and medially into the inguinal region (Figure 1). Disruption to the medial and lateral femoral fascia was noted, with clear delineation of the cranio-medial muscles of the femur, namely the rectus femoris and vastus medialis muscles. No disruption to underlying major neurovascular structures, including the femoral artery and vein, and saphenous nerve (branching from the femoral nerve) was noted.
Due to the level of associated trauma, the decision was made to surgically debride devitalised regions of the wound margins. Approximately 3-4mm of dermis was removed around the entire margin of the wound, revealing healthy (non-discoloured and bleeding) tissue. This resulted in a larger wound defect for closure.
Based on intraoperative wound margins, known tension lines, and specific intraoperative wound tension, the decision was made to undergo primary closure rather than other reconstructive flap procedures, such as axial pattern flaps. Where femoral fascia could be primarily apposed, 3/0 polydioxanone (PDS) was utilised in a simple interrupted or cruciate pattern. Likewise, the subcutaneous (and hypodermis for increased strength to prevent tearing) tissue was closed with simple interrupted walking sutures using 3/0 ‘Monosyn’ sutures.
This did result in an dereased wound tension but increased wound apposition. Throughout this procedure the coxofemoral and stifle joints were consistently extended and flexed to ensure adequate range of motion and associated wound tension levels. To finish, a 3/0 polypropylene suture was placed in a cruciate fashion, closing the wound into a Y-plasty at the level of the mid-femur region, with arms extending proximally towards the greater trochanter, medially towards the inguinal region, and distally towards the stifle. Increased tension was noted at the Y-junction yet deemed to not be an immediate concern.
The patient recovered and was discharged later that same day on the following medications: meloxicam 0.1 mg/kg PO q 24 hours for 10 days, paracetamol 15 mg/kg PO q 8 hours for five days, gabapentin 18 mg/kg PO q 12 hours for 10 days, and amoxicillin-clavulanic acid 23 mg/kg PO q 12 hours for seven days.
Outcome
Approximately five days postoperative, culture and sensitivity results returned, demonstrating a moderate growth of Staphylococcus aureus, resistant to amoxicillin, yet susceptible to previously dispensed amoxicillin-clavulanic acid (Figure 2.). The decision to not extend the antibiotic course was made. At seven days postoperative the patient presented for recheck review (Figure 3). The wound demonstrated good evidence of healing, with adequate dermal apposition, and no signs of dehiscence or infection. At the Y-junction a small region of bloody discharge was noted, likely due to a combination of movement and tension concentration at that level. Removal of this discharge revealed a well-opposed, healing wound bed. At 14 days postoperative, the patient presented for a final recheck review. Complete wound healing had occurred, with no further signs of infection, dehiscence or adverse tension. All external sutures were removed.
This case presents an interesting perspective on wound closure. So often we as practitioners desire to reach for advanced reconstructive or axial pattern flaps. We believe that large defects with high levels of tension and mobility must be addressed with complex repairs. Axial pattern flaps are known to increase the ability to close large defects without tension, and provide increased vascularity for wound beds with associated large direct cutaneous vessels, often resulting in excellent flap survival rates twice that of subdermal plexus flaps.1,2
Yet time after time, I am reminded that the principles of ‘KIS’ (Keep it Simple) are also applicable to reconstructive surgeries, and we might be surprised at just how well our patients can heal with simple yet effective surgical repairs.
Acknowledgement
Many thanks to Dr Louisa Ho Eckart (DACVS) for her specific case guidance and ongoing mentorship and motivation with soft-tissue reconstructive surgeries. She is an inspiration to all those around her.
References:
1. Tobias KM, Johnston SA. Veterinary surgery: Small animal-E-BOOK: 2-volume set: Elsevier Health Sciences; 2013.
2. Fossum TW. Small Animal Surgery E-Book: Elsevier Health Sciences; 2018.
Dr James Iversen
BVetBiol, BVSc (Hons), GCertSAECC
Surgical Resident (SA)
Animal Referral Hospital Canberra
Dr James Iversen is a small animal surgical resident at the Animal Referral Hospital (ARH) in Canberra. He has been working with ARH since 2021, where he initially began work as a small animal surgical intern, followed by a few years of emergency and critical care practice. During this time, he completed a Graduate Certificate of Small Animal Emergency and Critical Care at the University of Melbourne.
Dr Iversen enjoys all aspects of the profession, in particular analgesia, emergency, critical care, and as expected, all things surgical.
