A 40-year-old man presents to the Emergency department after being assaulted in the city centre. He sustained multiple knife wounds, including two in the left groin. On examination, there is reduced power of hip flexion and knee extension on the left, along with reduced sensation over the medial aspect of the left thigh. What is the probable cause of his symptoms?
Investigations revealed normal full blood count and biochemistry, with a glucose level of 5.6 mmol/L (3.0-6.0) and a prothrombin time of 11.5 s (11.5-15.5). A plain x-ray of the pelvis showed no evidence of fracture. The patient is a previously fit individual who smokes 10 cigarettes per day and drinks approximately 20 units of alcohol per week.