One week after the surgery, a blister appeared on the anteromedial skin of the ankle, near the arthroscopy portal. It was treated conservatively with wound care. However, increasing pain and swelling over the following days led the patient to consult in the emergency room. She denied any systemic symptoms such as fever or shiver­ing, but the ankle was swollen and had an ery­thematous area 2 cm in diameter around the arthroscopic wound. Upon opening the wound, purulent drainage suffused and was sent for bac­terial cultures. The patient’s laboratory evalua­tion revealed a normal white blood cell count, C-reactive protein (2.1 mg/L), and erythrocyte sedimentation rate (ESR, 45mm/h, with the nor­mal range being 0–20mm/h in our laboratory).

Methicillin-susceptible Staphylococcus aureus grew on cultures of intraoperative sam­ples, so an arthroscopic debridement and irriga­tion were performed within 2weeks of the initial

Antimicrobial therapy (systemic and/or local) cannot compensate for inadequate surgery.

Doppler, is a piezoelectric crystal embedded in a silicon sheath connected to an acoustic Doppler device [6, 17]. It is wrapped around either the pedicle vein or its artery and converts the ow detected through the vessel into a sound signal in real time [6]. Free ap failure risk is lower (risk ratio 0.4) and successful salvage rate is higher (risk ratio 1.73) when the implantable Doppler is used for monitorization than with clinical assess­ment and Doppler auscultation [4, 10, 18]. However, a wide range (0.75–37%) of false posi­tives (signal loss without free ap malfunction) has been reported [17], the higher end corre­sponding to studies with buried aps, in which a clinical assessment to compliment implantable Doppler information is not possible. False posi­tives can happen due to probe dislodgement, brin coating, or device malfunction, and result in unnecessary surgical revisions. There appear to be fewer false positives when the implantable Doppler is wrapped around arteries instead of veins [19], but as previously pointed out, venous compromise is more frequent than arterial throm­bosis so measuring venous ow is of more inter­est. Thus, many teams will combine the implantable Doppler information with clinical assessment and/or color duplex ultrasound to reduce the false-positive rate [12]. Additionally, vascular compromise needing surgical revision after pulling on the device’s wire to cut it (the piezoelectric crystal and part of the wire stays inside the patient) has been described [20]. These limitations result in that currently, the main use of the implantable Doppler is to monitor buried aps, in which most other forms of monitoring are not available (this circumstance is rare in the setting of FRI) [21].