Ultrasound-guided Genicular Nerve Block With Phenol for the Treatment of Chronic Pain Due to Knee Osteoarthritis
Status:
Unknown status
Trial end date:
2018-11-01
Target enrollment:
Participant gender:
Summary
Osteoarthritis (OA) is one of the most frequent causes of chronic pain, often intense,
debilitating and responsible for a large percentage of the elderly. The disease affects about
10% of adults and the knees are the most affected joints. The diagnosis of OA in the knee is
predominantly clinical, and can be confirmed by radiological examination. Systemic drugs are
indicated before invasive procedures, but pharmacological therapies may offer limited
benefits. Thermal radiofrequency lesions of genicular nerves has been used to relieve chronic
knee pain, as adjuvant therapy, but with high costs and low availability in the public
system. The use of phenol for peripheral analgesic blocks has emerged as a good option and at
low cost and can be used in any service of Pain Treatment. The aim of the study is to
evaluate the efficacy of 6% phenol for ultrasound-guided genicular nerves neurolysis for the
treatment of patients with chronic knee pain due to osteoarthritis.
METHODS: A prospective study will be carried out with 15 patients with chronic pain (more
than 4 months) and diagnosis of arthrosis by imaging, with pain intensity greater than 4
(from zero to 10) that will be submitted to ultrasound-guided genicular nerves block. The
test block will be performed with 0.25% -1,5 mL bupivacaine on each nerve. Patients who
present pain improvement> 50% will undergo neurolysis of genicular nerves with 1,5 mL of 7%
phenol in each of the genicular nerves. After the procedure, the patients will be evaluated
for 3 months in relation to the intensity of pain at rest and movement and duration of
analgesia provided by the intervention, range of movements and functionality of the knee
joint.