A 21-year old man with no co-morbidities was referred to the regional orthopedic unit from emergency department of another hospital in the vicinity, with the history of trivial injury to his right knee two days ago. He accidentally hit his right knee to the wall two days back and sustained an abrasion to his knee. He started complaining of pain in his knee the next day and had to stop working. Pain got worse over night and he attended the emergency department the next day, from where he was referred to us with the suspicion of septic arthritis or cellulitis. He received intra-venous benzyl-penicillin and flucloxacillin in the emergency department.
On arrival, he was afebrile and systemically stable but in considerable pain. Examination of the right knee revealed small superficial wound over patella, slight redness and increased temperature in surrounding area with grade I effusion in the joint. Movements of the joint was reduced and associated with severe pain. Neurological and vascular examination of the limb was satisfactory.
The initial blood investigation revealed white cell count (WCC) count of 18.6 × 109/L, C-reactive protein (CRP) of 63.1 mg/L, and hemoglobin (Hb) level of 15 g/dL. X ray of the right knee did not show any bony injury or gas in the soft tissues. A working diagnosis of septic arthritis secondary to traumatic wound was made and urgent arthroscopic washout of the knee was performed that night. Arthroscopy revealed inflamed synovium and only 10 cc of fluid was drained from the knee. Urgent microscopy and gram stain of the fluid and later culture failed to reveal any organism.
Post-operatively, intravenous flucloxacillin and benzyl penicillin was continued along with gentamycin. Even after 72 hours of antibiotics patient remained symptomatic. Although he remained afebrile at all times, his pain and tenderness continued to increase in distal thigh and blood investigations revealed a marked increase in inflammatory markers (CRP of 181 and ESR of 37). Considering the failure to respond with intravenous antibiotics, negative arthroscopy and increasing tenderness in distal thigh, a suspicion of necrotizing fasciitis was made. Urgent contrast enhanced Computed Tomogram (CT) scan (Fig ) of his right thigh and knee was performed that revealed marked inflammatory stranding and low attenuation with suspicion of necrosis mainly in rectus femoris and vastus lateralis. Patient was taken to theatre urgently and fasciotomy performed through antero-lateral approach of the thigh which confirmed the CT findings of necrotic fascia and muscles (Fig and ). Thorough debridement of rectus femoris and vastus lateralis was performed, wound was washed thoroughly and packed with betadine soaked swabs.
CT scan of right thigh, showing inflammatory stranding and low attenuation in vastus latralis (arrow).
Intra-operative picture of surgical debridement of thigh through antero-lateral approach.
Intra-operative picture showing necrotic fascia and subcutaneous tissue as evident by lack of bleeding (arrow).
The case was discussed with microbiologist and intra-venous (IV) clindamycin and ciprofloxacin was added along with flucloxacillin and benzyl penicillin. IV hydration and oxygen therapy was maintained through out, with close observation of renal functions which remained stable.
Patient was taken to theatre again in 48 hours for re examination which showed more necrotic area in rectus muscle which was debrided again. Further two washouts with 48 hours interval, did not show any progression of necrosis and wound was closed gradually with staples and shoe lace technique. IV antibiotics were continued for 14 days followed by oral clindamycin and ciprofloxacin for 5 weeks. He remained stable systemically and responded well to the treatment as evidenced by normalizing inflammatory markers. The diagnosis was confirmed on tissue histology but causative organism remained unidentified.
Patient made an amazing recovery from this limb and life threatening condition which was made possible by multi-disciplinary approach involving orthopedics, general surgery, radiology, microbiology, physiotherapy and dieticians. Patient was discharged home after 19 days of in-hospital stay. At final follow up 3 months later he had full range of motion in his right knee and grade 4 power in knee extensors.