Phenol Neurolysis of Genicular Nerves for Chronic Knee Pain

Northwestern University

Status and phase: Withdrawn; Phase 4

Conditions: Pain, Chronic

Treatments: Drug: Methylprednisolone Injection; Drug: Phenol Injection

Study type: Interventional

Funder types: Other

Identifiers

NCT03973177

STU00209591

Details and patient eligibility

About

Chronic knee pain from osteoarthritis (OA) is commonly treated with total knee arthroplasty (TKA) when conservative therapies fail to provide pain relief. More than 600,000 TKAs are performed in the U.S. annually, a number that continues to increase. A logistic-regression model suggests that the incidence rate of TKA will increase by 143% in the United States by 2050 compared to 2012. Although TKA is successful in reducing knee pain and joint stiffness in most cases, it can be associated with a 7-35% incidence of persistent refractory post-surgical knee pain.

Aim:

To determine whether chemical neurolysis of the genicular nerves with 6% aqueous phenol is non-inferior in reducing knee pain as compared to corticosteroid injection of the genicular nerves, in patients with refractory chronic knee pain for more than 6 months after total knee replacement.

Hypothesis:

Chemical neurolysis of genicular nerves with phenol will provide equal or superior pain relief than corticosteroid genicular nerve injections at 3 months, as measured by the Oxford Knee Score.

Sex: All

Ages: 40 to 95 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Ages 40-95 years
• Patients with knee pain, on average > 4 (NRS) persisting more than 6 months after TKA
• Willingness to undergo image guided diagnostic nerve block and the study intervention

Exclusion criteria

• Pain score (NRS) < 4 at time of study enrollment
• Conditions that preclude the diagnostic block or the study intervention (e.g., irreversible coagulopathy or bleeding disorder, allergic reaction/contraindication to local anesthetic, contrast dye, steroids, and/or phenol, pregnancy, severe or uncontrolled medical illness).
• Evidence of indolent infection of the knee prosthesis (elevated C-reactive protein assessed when clinically indicated)
• Inability to write, speak, or read in English
• Pregnancy

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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0 participants in 2 patient groups

Treatment Group: Phenol injection

Experimental group

Description:

6% aqueous phenol 2.5 mL will be mixed with 0.5 mL iopamidol 300 and will be injected at each target sites

Treatment:

Drug: Phenol Injection

Control Group: Methylprednisolone injection

Other group

Description:

Methylprednisolone acetate 10 mg with 2 mL preservative free saline and 0.5 mL iopamidol 300 will be injected at each of the target site

Treatment:

Drug: Methylprednisolone Injection