A 35-year-old female is brought to the trauma centre after a motor vehicle collision in which her right leg was trapped under the vehicle for approximately 20 minutes. On examination, there is a 2.5 cm laceration over the anterior tibia with visible bone ends, and the wound is contaminated with road debris and grease. Examination of the foot reveals absent dorsalis pedis pulse and diminished sensation in the first web space. The posterior tibial pulse is faintly palpable. X-ray shows a comminuted tibial fracture. What is the Gustilo grade of this fracture, and what is the most critical next step?

Explanation

## Gustilo Grade III C: Vascular Injury Requiring Repair This patient has an open fracture with vascular compromise requiring immediate vascular intervention — the hallmark of Grade III C. The absent dorsalis pedis pulse with diminished sensation in the first web space (anterior tibial nerve distribution) indicates anterior tibial artery injury. ### Distinguishing Grade III B from Grade III C | Feature | Grade III B | Grade III C | |---------|-----------|------------| | Vascular Status | Compromised (absent/diminished pulses) | **Arterial injury requiring surgical repair** | | Nerve Injury | May occur | Often present | | Soft Tissue Damage | Extensive with periosteal stripping | Extensive | | Prognosis | High amputation risk | **Amputation risk highest** | | Management | Vascular assessment + repair | **Urgent vascular surgery** | ### Key Point: **Grade III C is defined by the presence of an arterial injury requiring vascular repair, regardless of wound size or soft tissue damage.** The absent dorsalis pedis pulse indicates anterior tibial artery compromise — this mandates Grade III C classification. ### Clinical Pearl: **The "C" in Grade III C stands for "Compromised vascular status requiring repair."** Any open fracture with vascular injury requiring operative repair (angiography, thrombectomy, graft, or anastomosis) is Grade III C, even if soft tissue damage is less extensive than Grade III B. ### High-Yield: **Absent pulses in an open fracture = Grade III C until proven otherwise.** The posterior tibial pulse being faintly palpable does not exclude anterior tibial artery injury — the absent dorsalis pedis pulse is the critical finding. Vascular surgery must be consulted urgently; amputation rates for Grade III C exceed 50% if revascularization is delayed beyond 6–8 hours. ### Mnemonic: **"III C = Compromised (arterial injury); requires urgent vascular surgery within 6–8 hours"** ### Management Algorithm for Grade III C ```mermaid flowchart TD A[Open fracture with absent pulses]:::outcome --> B{Vascular injury suspected?}:::decision B -->|Yes| C[Grade III C]:::outcome C --> D[Stat vascular surgery consult]:::action D --> E[Angiography or CTA]:::action E --> F{Revascularization feasible?}:::decision F -->|Yes| G[Urgent vascular repair + fracture fixation]:::action F -->|No| H[Amputation]:::urgent G --> I[Broad-spectrum antibiotics + tetanus]:::action I --> J[Debridement within 3 hours]:::action ``` [cite:Rockwood & Green's Fractures in Adults 9e Ch 1; Campbell's Operative Orthopaedics 13e Ch 58]