The management of concomitant septic arthritis of the knee and femoral osteomyelitis - A case series and literature review

Abstract

We present a case series comprising three patients with concomitant septic arthritis of the knee and osteomyelitis of the femur. Early advanced imaging rendered the accurate diagnosis of the condition and the appropriate surgical approach and technique used to treat the infection. Repeated extensive surgical debridement, irrigation and insertion of antibiotic-impregnated cement rod into the femur were required, in addition to long term antibiotics. The infection in all three cases was eradicated successfully. Following a period of physical rehabilitation, they had fairly preserved independent ambulatory function. We advocate a high index of suspicion of this condition with subsequent early advanced imaging for a timely diagnosis. In addition, we described our challenges in the fabrication process of the antibiotic-impregnated cement rod.

Keywords: Antibiotic-impregnated cement rod; Femur; Infection; Knee; Osteomyelitis; Septic arthritis.

Fig. 1

a Lateral view of the plain radiograph of the left knee showing a large suprapatellar effusion with no signs of bony erosion. T2-weighted MR image of the left knee revealing rim-enhancing collections (b,arrow) in the posterior knee.

Fig. 2

Intraoperative findings revealing pus and necrotic tissue in the posterior knee.

Fig. 3

Repeat MRI showing interval worsening of the abscesses with enhancement of intramedullary signals in the femur indicating osteomyelitis.

Fig. 4

Plain radiographs showing cortical expansion of the distal femur.

Fig. 5

T2-weighted image showing a multiloculated medial thigh abscess with increased signals (arrow) in the distal femur.

Fig. 6

a Plain radiographs showing periosteal thickening of the distal femur (arrow). MRI showing enhanced intramedullary signals in the distal femur (b, arrowhead).