Ultrasound-Guided Lateral Femoral Cutaneous Nerve Cryoneurolysis for Analgesia in Patients With Burns

Abstract

Autologous skin grafting from the thigh is frequently required for treatment of burns and is associated with intense pain at the donor site. Local anesthetic–based (LA) nerve blocks of the lateral femoral cutaneous nerve (LFCN) have been demonstrated to provide analgesia when the graft is taken from the lateral thigh. However, the duration of these single injection blocks has been reported to average only 9 hours, whereas the pain from the procedure lasts days or weeks. Continuous LA nerve blocks can also be used to provide analgesia during serial debridement of burns, although this requires placement of a perineural catheter which may increase infection risk in a population with an increased susceptibility to infection. Cryoneurolysis of the LFCN can potentially provide analgesia of the lateral thigh for skin graft harvesting or serial burn debridement that lasts far longer than conventional LA nerve blocks. Here, we present a series of three patients who received a combination of a LA nerve block and cryoneurolysis nerve block of the LFCN for analgesia of the lateral thigh. Two of these patients had the blocks placed before harvesting a split thickness skin graft. The third received the blocks for outpatient wound care of a burn to the lateral thigh. In all cases, the resulting analgesia lasted more than 1 week. A single cryoneurolysis block of the LFCN successfully provided extended duration analgesia of the lateral thigh for autologous skin graft donor site or wound care of a burn in three patients.

Cryoneurolysis and Percutaneous Peripheral Nerve Stimulation to Treat Acute Pain

“…Similarly, cryoneurolysis may provide palliative analgesia during end-of-life care, 22 or pain control during weeks of postburn debridement and redressing of an extremity. 51,55 Relatedly, split-thickness skin grafts are frequently harvested from the lateral thigh, and cryoneurolysis of the lateral femoral cutaneous nerve has been used to provide multiple weeks of potent analgesia. 55 Pain after knee arthroplasty is notoriously challenging to treat and frequently lasts multiple weeks or even months, 93 and consequently may be a suitable procedure for cryoneurolysis.…”

“…51,55 Relatedly, split-thickness skin grafts are frequently harvested from the lateral thigh, and cryoneurolysis of the lateral femoral cutaneous nerve has been used to provide multiple weeks of potent analgesia. 55 Pain after knee arthroplasty is notoriously challenging to treat and frequently lasts multiple weeks or even months, 93 and consequently may be a suitable procedure for cryoneurolysis. 94 However, application to the femoral nerve at the inguinal ligament or even more distally within the adductor canal has a high probability of inducing quadriceps weakness.…”

“…In general, even probes with trocar tips require a sharper introducer such as an intravenous angiocatheter to enable passage through the skin and muscle to the target nerve; so, it is unclear how beneficial hemispherical/blunt tips are in practice. [54][55][56]92 Ice balls are easiest to visualize with high-frequency linear transducers, but power Doppler may improve imaging with low-frequency linear-array transducers used for deeper structures. 109 Because of the hyperechoic border of the ice ball resulting from the higher acoustic impedance at the border between frozen and unfrozen tissues, [110][111][112] acoustic shadowing can limit visualization when the nerve is deeper than the ice ball.…”

“…125 For superficial areas, injecting a tumescent layer of local anesthetic or saline below the dermis can push the nerve deeper and increase the margin of safety. 55 Additionally, trident probes specifically designed for treating subdermal nerves are available with heated elements to protect the dermis and epidermis ("trident" probe, fig. 1).…”

Sonographic features of the lateral femoral cutaneous nerve in meralgia paresthetica

“…It is easier to identify the LFCN by ultrasound, and the anatomical variation of the LFCN can be viewed with high-frequency ultrasound Original Article Sonographic features of the lateral femoral cutaneous nerve in meralgia paresthetica (3,4). However, the clinical application of ultrasound in the LFCN mainly focuses on regional nerve block as a guide (5,6). There are few reports regarding the ultrasound diagnosis of lateral femoral cutaneous neuritis.…”