Medical Policy

 

Subject: Genicular Nerve Blocks and Ablation for Chronic Knee Pain
Document #: SURG.00142 Publish Date:    12/12/2018
Status: Reviewed Last Review Date:    11/08/2018

Description/Scope

This document addresses genicular nerve blocks and genicular radiofrequency ablation, also called genicular neurotomy, genicular denervation or cooled radiofrequency therapy, as a treatment for the management of chronic knee pain.

Note: Please see the following related documents for additional information:

Position Statement

Investigational and Not Medically Necessary:

Genicular nerve blocks and genicular nerve ablation are considered investigational and not medically necessary for the treatment of chronic knee pain, including but not limited to any of the following:

Rationale

Genicular nerve blocks and genicular radiofrequency ablation are being evaluated in the treatment of chronic knee pain for individuals that have not been effectively managed by pharmacologic or other alternative therapies. A search of the peer-reviewed medical literature identified studies evaluating the use of nerve blocks for the diagnosis and treatment of neuralgias and neuropathic pain conditions; however, there is a lack of adequately designed trials in the peer-reviewed literature concerning the use of genicular nerve blocks and radiofrequency ablation as treatments for chronic knee pain.

In a 2011 randomized controlled trial by Choi and colleagues, the authors investigated whether radiofrequency ablation applied to articular nerve branches (genicular nerves) was effective in treating chronic knee joint osteoarthritis pain. The 38 study participants (who had severe knee osteoarthritis lasting longer than 3 months) were randomized to two treatment arms; radiofrequency ablation (n=19) or control group (n=19). Using a visual analog scale, Oxford knee scores, and global perceived effect on a 7-point scale, measurements were taken at baseline, and at 1, 4, and 12 weeks following the procedure. At the 4-week point, the visual analog scores showed the radiofrequency group had less knee joint pain than the control group. Similar findings were noted in the Oxford knee scores. There were no post-procedure adverse events reported during the follow-up period. While this study showed pain reduction in those with chronic knee osteoarthritis pain, the authors concluded that “further trials with larger sample size and longer follow-up are warranted.”

In a 2016 randomized study by Qudsi-Sinclair and colleagues, 28 participants with continued knee pain following total knee arthroplasty were evaluated after having received traditional radiofrequency (n=14) or local anesthetic and corticosteroid block of the genicular nerves in the knee (n=14). In this double-blind, randomized study, the participants were followed for 1 year. During the first 3 to 6 months, an improvement in joint function and a reduction in pain were shown, with the results being similar between the two treatment arms. While the study showed improvement in both groups, the sample size was small and the authors noted that further studies should be done with larger sample sizes to determine if there are any long-term adverse effects.

A retrospective review by Innaccone and colleagues (2017) looked at the records of 31 individuals who had radiofrequency ablation of the genicular nerves with analysis of the degree and duration of pain relief following the procedure. In this study population, the majority of individuals had tried at least some type of conservative treatment (physical therapy, steroid or hyaluronic acid injection, oral analgesics) prior to radiofrequency ablation. Out of the 31 participants, 23 were available at a 3-month follow-up with 14/23 participants continuing to describe pain relief. A total of 20 participants were available for a 6-month follow-up and 95% of those participants reported pain relief. While most participants reported pain relief, limitations of the study include retrospective chart review with prospective follow-up, small sample size, lack of a control group, and direct comparison to other conservative treatment measures.

Another retrospective chart review with prospective follow-up by McCormick and colleagues (2017) reported on 33 participants who had previously received genicular nerve blocks and cooled radiofrequency ablation for the treatment of chronic pain from knee osteoarthritis. Primary outcome measure was defined as a combination of 50% or greater reduction in pain numeric rating scale (NRS), Patient Global Impression of Change (PGIC) score consistent with “very much improved” or “improved,” and no total knee arthroplasty. A total of 25 participants were available for survey 6 months following the procedure. The median reduction in pain was 2 on the NRS scale. A PGIC score consistent with “very much improved” or “improved” was achieved after 35% of procedures (95% confidence interval [CI] 22%–48%). This study has limitations including its retrospective nature and survey design. Prospective studies with larger sample sizes are necessary.

Santana Pineda and colleagues (2017) reported on a prospective study in which 25 participants with chronic osteoarthritis of the knee received radiofrequency ablation of genicular nerves. Follow-up evaluations were done at 1, 6, and 12 months after the procedure. Primary outcome measure was the change from baseline knee pain using visual analog scores. Those who reported an improvement of 50% or greater in pretreatment visual analog scores 1, 6, and 12 months following intervention were 22/25 (88%), 16/25 (64%) and 8/25 (32%), respectively. While improvement was noted following the radiofrequency procedure, the authors stated that “Larger-scale studies are needed to confirm the results and address the safety aspects in other populations.”

In a 2018 study by Davis and colleagues, the authors reported on the safety and efficacy of genicular cooled radiofrequency ablation compared to intra-articular steroid injection for individuals with osteoarthritis of the knee. In this prospective, randomized, cross-over trial, study participants were included if they had a known diagnosis of osteoarthritis of the knee, complaints of knee pain for at least 6 months that was unresponsive to conservative treatment, NRS pain score of 6 or greater, Oxford Knee Score (OKS) of 35 or less, positive diagnostic genicular nerve block (defined as a decrease of ≥ 50% in NRS score); and if the participant was taking an opioid or other morphine-equivalent medication, the dose was clinically stable. Participants were allowed to use analgesics as needed during the study. A total of 138 participants proceeded to treatment; 67 participants received genicular cooled radiofrequency ablation and 71 participants received intra-articular steroid injection. Participants were assessed at baseline and at 1, 3, and 6 months following treatments. After 6 months of treatment, the participants randomized to the intra-articular steroid cohort were allowed to “cross over” and receive cooled radiofrequency ablation. Using the 11-point NRS, the primary efficacy outcome was the proportion of participants whose knee pain was reduced by 50% or greater from baseline at 6 months after treatment. Secondary outcomes included change in knee function detected by OKS, participant perception of treatment effect as reflected by the Global Perceived Effect (GPE) score, and opioid and nonopioid (nonsteroidal anti-inflammatory drugs) analgesic use measured by self-reported average daily dosage used. The mean baseline pain scores in the cooled radiofrequency group were 76; 7.3 ± 1.2 and were 75; 7.2 ± 1 in the intra-articular steroid group. At the 6 month visit, the NRS score was 2.5 ± 2.3 in the cooled radiofrequency group (n=58) and 5.9 ± 2.2 (n=68) in the intra-articular steroid group. A total of 43/58 (95% CI, 62.9–85.4) participants in the cooled radiofrequency group and 11/68 (95% CI, 7.4–24.9) in the intra-articular steroid group had ≥ 50% reduction in NRS score at 6 months. The mean OKS in each study cohort was equivalent at baseline and mean OKS improved at all end points in both study groups. At 6 months, 53/58 (95% CI, 83.9–98.8) participants in the cooled radiofrequency ablation cohort reported improved global perceived effect compared to 16/67 (95% CI, 13.4–34.4) of the participants in the intra-articular steroid group. At baseline, 33 participants in the cooled radiofrequency group required nonopioid medication and 34 participants in the intra-articular steroid group required nonopioid medication. At 6 months, mean nonopioid drug dose use was −34.5 ± 128.9 mg in the cooled radiofrequency group and 135.5 ± 391 mg in the intra-articular steroid group. No procedure-related serious adverse events were reported. At 6 months, 74.1% of cooled radiofrequency ablation participants reported reduced index knee pain by at least 50% compared to 16.2% in participants treated with intra-articular steroid injections. GPE improved in 91% of the cooled radiofrequency group compared to 24% in the intra-articular steroid group. Opioid analgesic use was not different between the two groups and remained similar to baseline use. While this study suggests that compared with a single intra-articular steroid injection, cooled radiofrequency ablation provides a reduction in knee pain associated with improved knee function, there are several limitations to this study. The participants received only one intra-articular steroid injection over a 6-month period, the study was not blinded and the study questionnaires were self-administered. There was a lack of a true control group since intra-articular steroid injections are considered analgesics. There was no formal recording of medication usage in this study which allowed for the potential for error and/or inability to identify acute changes in medication dosage during the study. Since participants in both study groups used opioids for medical indications other than osteoarthritis-related knee pain, the effect of each treatment on opioid use could not be specifically measured. Further studies with a true control group and consistent tracking of additional medication usage are necessary to determine efficacy of genicular cooled radiofrequency ablation for osteoarthritis-related knee pain.

In a 2017 meta-analysis by Gupta and colleagues, the authors included 17 studies in which radiofrequency ablation procedures were done for chronic knee pain. Five (5) of the studies were randomized controlled trials with small population groups, 8 were prospective or retrospective case series, and 4 were case reports. Three different types of radiofrequency ablation procedures were performed; conventional, pulsed, or cooled. The three differing methodologies makes it difficult to compare the effectiveness of radiofrequency ablation. Among the studies included, there is a lack of consistent evidence regarding adverse events. With inconsistent procedural methodologies, inconsistent assessment measures, and small study sizes, it is difficult to apply any specific study to clinical practice.

At this time there is a lack of literature with true head-to-head comparisons to other standard treatments. Published studies lack control groups, have small group sizes, or have serious methodologic problems that prevent the drawing of treatment-guiding conclusions from their results.

Background/Overview

Chronic osteoarthritis of the knee is one of the most common diseases of advanced age. With up to 20 million adults in the United States suffering from osteoarthritis of the knee, close to 700,000 cases progress to total knee joint replacement. Many individuals with chronic joint pain, however, are not candidates for invasive procedures due to body mass index, age and other comorbidities. Alternative therapies including arthroscopic debridement or injections are associated with less than optimal clinical outcomes. In addition to osteoarthritis, adults can experience knee pain due to a number of other causes, and an estimated 10-34 % of individuals experience long-term pain after a total knee replacement.

When an individual exhibits knee pain, the pain signals can be generated from the peripheral nerves innervating the knee including several branches of the genicular nerve. A diagnostic genicular nerve block consists of placing a small amount of local anesthetic, on the genicular nerves to determine if there is sufficient pain relief in the knee to justify performing a therapeutic neurotomy. Radiofrequency ablation of the genicular nerves is then performed to restore function and alleviate knee pain.

Definitions

Osteoarthritis: A degenerative condition of the joints that causes destruction of the material in the joints that absorbs shock and allows proper movement.

Radiofrequency ablation: A surgical procedure where diseased cells are destroyed using heat produced by high-frequency radio waves.

Coding

The following codes for treatments and procedures applicable to this document are included below for informational purposes. Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy. Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services are Investigational and Not Medically Necessary:

CPT

 

 

64450

Injection, anesthetic agent; other peripheral nerve or branch [when specified as genicular nerve block]

 

64640

Destruction by neurolytic agent; other peripheral nerve or branch [when specified as ablation of genicular nerve(s)]

 

64999

Unlisted procedure, nervous system [when specified as cooled or pulsed RF therapy (not destruction) to genicular nerve(s)]

 

 

 

 

ICD-10 Diagnosis

 

M08.861-M08.869

Other juvenile arthritis, knee

M08.961-M08.969

Juvenile arthritis, unspecified, knee

M12.561-M12.569

Traumatic arthropathy, knee

M12.861-M12.869

Other specific arthropathies, not elsewhere classified, knee

M13.161-M13.169

Monoarthritis, not elsewhere classified, knee

M13.861-M13.869

Other specified arthritis, knee

M17.0-M17.9

Osteoarthritis of knee

M21.061-M21.069

Valgus deformity, not elsewhere classified, knee

M21.161-M21.169

Varus deformity, not elsewhere classified, knee

M21.261-M21.269

Flexion deformity, knee

M22.00-M22.92

Disorder of patella

M23.000-M23.92

Internal derangement of knee

M24.361-M24.369

Pathological dislocation of knee, not elsewhere classified

M24.461-M24.469

Recurrent dislocation, knee

M24.561-M24.569

Contracture, knee

M24.661-M24.669

Ankylosis, knee

M25.361-M25.369

Other instability, knee

M25.561-M25.569

Pain in knee

M25.661-M25.669

Stiffness of knee, not elsewhere classified

M25.761-M25.769

Osteophyte, knee

M25.861-M25.869

Other specified joint disorders, knee

M66.0

Rupture of popliteal cyst

M67.361-M67.369

Transient synovitis, knee

M67.461-M67.469

Ganglion, knee

M67.50-M67.52

Plica syndrome

M67.861-M67.869

Other specified disorders of synovium and tendon, knee

M70.40-M70.42

Prepatellar bursitis

M70.50-M70.52

Other bursitis of knee

M71.20-M71.22

Synovial cyst of popliteal space

M71.561-M71.569

Other bursitis, not elsewhere classified, knee

M92.40-M92.42

Juvenile osteochondrosis of patella

M92.50-M92.52

Juvenile osteochondrosis of tibia and fibula

M94.261-M94.269

Chondromalacia, knee

S80.00XA-S80.02XS

Contusion of knee

S83.101A-S83.196S

Subluxation and dislocation of knee

S83.401A-S83.92XS

Sprain of knee

S87.00XA-S87.02XS

Crushing injury of knee

T84.84XA-T84.84XS

Pain due to internal orthopedic prosthetic devices, implants and grafts

Z96.651-Z96.659

Presence of artificial knee joint

References

Peer Reviewed Publications:

  1. Choi WJ, Hwang SJ, Song JG, et al. Radiofrequency treatment relieves chronic knee osteoarthritis pain: a double-blind randomized controlled trial. Pain. 2011; 152(3):481-487.
  2. Davis T, Loudermilk E, DePalma M et al. Prospective, multicenter, randomized, crossover clinical trial comparing the safety and effectiveness of cooled radiofrequency ablation with corticosteroid injection in the management of knee pain from osteoarthritis. Reg Anesth Pain Med. 2018; 43(1):84-91.
  3. Gupta A, Huettner DP, Dukewich M. Comparative effectiveness review of cooled versus pulsed radiofrequency ablation for the treatment of knee osteoarthritis: a systematic review. Pain Physician. 2017; 20(3):155-171.
  4. Iannaccone F, Dixon S, Kaufman A. A review of long-term pain relief after genicular nerve radiofrequency ablation in chronic knee osteoarthritis. Pain Physician. 2017; 20(3):E437-E444.
  5. McCormick ZL, Korn M, Reddy R, et al. Cooled radiofrequency ablation of the genicular nerves for chronic pain due to knee osteoarthritis: six-month outcomes. Pain Med. 2017; 18(9):1631-1641.
  6. Protzman NM, Gyi J, Malhotra AD, Kooch JE. Examining the feasibility of radiofrequency treatment for chronic knee pain after total knee arthroplasty. PM R. 2014; 6(4):373-376.
  7. Qudsi-Sinclair S, Borrás-Rubio E, Abellan-Guillén JF, et al. A comparison of genicular nerve treatment using either radiofrequency or analgesic block with corticosteroid for pain after a total knee arthroplasty: a double-blind, randomized clinical study. Pain Pract. 2017; 17(5):578-588.
  8. Santana Pineda MM, Vanlinthout LE, Moreno Martín A, et al. Analgesic effect and functional improvement caused by radiofrequency treatment of genicular nerves in patients with advanced osteoarthritis of the knee until 1 year following treatment. Reg Anesth Pain Med. 2017; 42(1):62-68.
Websites for Additional Information
  1. American Academy of Orthopaedic Surgeons. Osteoarthritis. Available at: http://orthoinfo.aaos.org/topic.cfm?topic=a00227. Accessed on October 11, 2018.
  2. American College of Rheumatology. Osteoarthritis. Available at: http://www.rheumatology.org/I-Am-A/Patient-Caregiver/Diseases-Conditions/Osteoarthritis. Accessed on October 11, 2018.
  3. Centers for Disease Control. Osteoarthritis. Available at: http://www.CDC.gov/arthritis/osteoarthritis.htm. Accessed on October 11, 2018.
Index

Osteoarthritis
Radiofrequency ablation

Document History

Status

Date

Action

Reviewed

11/08/2018

Medical Policy & Technology Assessment Committee (MPTAC) review. Updated Rationale and References sections.

Reviewed

02/27/2018

MPTAC review. The document header wording updated from “Current Effective Date” to “Publish Date.” Updated Rationale and References sections.

Reviewed

02/02/2017

MPTAC review. Updated Rationale and References sections.

New

02/04/2016

MPTAC review. Initial document development.