RECORGEN: Patients With Chronic Knee Pain Treated With Conventional Radiofrequency of the Genicular Nerves

• Sponsor: Ziekenhuis Oost-Limburg (Other)
• Overall Status: Completed
• CT.gov ID: NCT04234984
• Collaborator: (none)
• Enrollment: 66
• Location: 1
• Actual Duration (Months): 9.7
• Patients Per Site Per Month: 6.8

Study Details

Study Description

Brief Summary

Management of chronic knee pain remains a challenge to the treating physician. A radiofrequency treatment of the genicular nerves is a not yet established but promising technique. This procedure is minimal invasive and has few adverse events. For these reasons it can be advantageous and fulfilling the unmet needs of these chronic knee pain patients warranting further research of its efficacy.

To investigate this efficacy, all patients treated with radiofrequency ablation in the multidisciplinary chronic pain center between 1 September 2017 and 31 December 2019 with exclusion of patients with chronic widespread pain, will be retrospectively analyzed in a single-center cohort.

Condition or Disease	Intervention/Treatment	Phase
Chronic Knee Pain

Detailed Description

This project has as primary objective the evaluation of treatment success of a conventional radiofrequency treatment of the genicular nerves in patients diagnosed with chronic knee pain due to osteoarthritis of the knee or persistent post-surgical pain (PPSP) at six weeks post treatment. Secondary objectives are evaluation of treatment effect at a third time point at the end of the inclusion period, subgroup analysis of treatment success based on indication to treatment, evaluation of subjective functional improvement and change in analgesics, estimation of the duration of effect of the treatment and adverse events.

This study includes all patients treated with radiofrequency ablation in the multidisciplinary chronic pain center in Ziekenhuis Oost-Limburg, Campus Sint-Barbara between 1 September 2017 and 31 December 2019 with exclusion of patients with chronic widespread pain.

The main study outcome is the proportion of patients with a global perceived effect of at least 50% at 6 weeks post intervention. Secondary outcomes include reduction in pain intensity, measured by Numeric Rating Scale (NRS) at six weeks and at a third time point, global perceived effect at a third time point, subjective change in physical functioning, duration effect of the treatment, use of strong opioids, and adverse events.

Study Design

• Study Type: Observational
• Actual Enrollment: 66 participants
• Observational Model: Cohort
• Time Perspective: Retrospective
• Official Title: A Retrospective Single-center Cohort Study on Patients With Chronic Knee Pain Treated With Conventional Radiofrequency of the Genicular Nerves
• Actual Study Start Date: Jan 26, 2020
• Actual Primary Completion Date: Nov 15, 2020
• Actual Study Completion Date: Nov 15, 2020

Arms and Interventions

Arm	Intervention/Treatment
Conventional radiofrequency (RF) treatment All patients with chronic knee pain who qualify for a conventional RF treatment of the genicular nerves

Outcome Measures

Primary Outcome Measures

1. The Number of Patients Reaching Treatment Succes at 6 Weeks Defined as Global Perceived Effect (GPE) of ≥ 50% Compared to Baseline. [6 weeks after treatment]

   Treatment success is defined as a global perceived effect (GPE) of at least 50% at measurement time point compared to baseline. Global perceived effect (GPE) scales are used as an overall outcome measure for patients with pain, as they may cover additional aspects to pain relief and physical function that are important to the individual. Patients are asked to response on the question of how the treatment influenced the pain symptoms. The patients were asked to expres their answer in percentage where 0 % ( no improvement) to 100 (total improvement, the symptoms are gone).

Secondary Outcome Measures

1. The Number of Participants With NRS Reduction ≥50% Compared to Baseline [6 weeks after treatment]

   The numeric rating scale (NRS) is used to assess pain intensity varying from 0 (no pain) to 10 (intense pain). This scale was retrieved retrospectively out of the patient file. NRS reduction ≥50% is calculated using the NRS at 6 weeks compared to the NRS at baseline.

2. The Patient's NRS [after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure]

   The numeric rating scale (NRS) is used to assess pain intensity varying from 0 (no pain) to 10 (intense pain). This scale will be asked telephonically to the patient.

3. The Number of Patients With Subjective Increase in Physical Functioning at the Second Time Point [after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure]

   The question 'Do you experience at the moment functional improvement in comparison with before the treatment?' is asked telephonically to the patient. The possible answers are 'no increase in physical functioning' and ' yes, there was an increase in physical funcitoning'. An increase in physical functioning is the best outcome.

4. The Number of Pariticipants Using Strong Opioids [6 weeks after treatment]

   The change in use of strong opioids is retrieved retrospectively out of the patient file. The answer to the use of strong opioids is yes or no. No use of strong opioids is a better outcome.

5. Strong Opioid Use at the Second Time Point [after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure]

   The change in use of strong opioids is asked telephonically to the patient.

6. The Number of Participants Reaching Treatment Success After Retrieval of the Informed Consent Defined as GPE of ≥ 50% Compared to Baseline. [after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure]

   Treatment success is defined as a global perceived effect (GPE) of at least 50% at measurement time point compared to baseline. Global perceived effect (GPE) scales are used as an overall outcome measure for patients with pain, as they may cover additional aspects to pain relief and physical function that are important to the individual. Patients are asked to response on the question of how the treatment influenced the pain symptoms. The patients were asked to expres their answer in percentage where 0 % ( no improvement) to 100 (total improvement, the symptoms are gone).

7. Number of Participants With Post-treatment Complications [6 weeks after treatment.]

   Adverse events related to the conventional radiofrequency therapy will be assessed. This will be assessed retrospectively in the patient file according to the standard of care consultation at 6 weeks after treatment.

8. Number of Participants With Post-treatment Complications [after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure]

   Adverse events related to the conventional radiofrequency therapy will be assessed telephonically

Eligibility Criteria

Criteria

• Ages Eligible for Study: 18 Years and Older
• Sexes Eligible for Study: All

Inclusion Criteria:

• All patients with chronic knee pain who qualify for a conventional RF treatment of the genicular nerves

Exclusion Criteria:

• A negative diagnostic block with lidocaine 2% 1 ml of the three genicular nerves defined as less than 50% pain reduction

• Chronic widespread pain

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Ziekenhuis Oost-Limburg	Genk		Belgium	3600

Sponsors and Collaborators

• Ziekenhuis Oost-Limburg

Investigators

• Principal Investigator: Jan Van Zundert, MD PhD, Ziekenhuis Oost-Limburg

Study Documents (Full-Text)

• Study Protocol and Statistical Analysis Plan - Jun 19, 2020

More Information

Publications

None provided.

• Responsible Party: Jan Van Zundert, Principal Investigator, Ziekenhuis Oost-Limburg
• ClinicalTrials.gov Identifier: NCT04234984
• Other Study ID Numbers: RECORGEN
• First Posted: Jan 21, 2020
• Last Update Posted: Jun 14, 2022
• Last Verified: Mar 1, 2022

• Studies a U.S. FDA-regulated Drug Product: No
• Studies a U.S. FDA-regulated Device Product: No
• Keywords provided by Jan Van Zundert, Principal Investigator, Ziekenhuis Oost-Limburg: Conventional radiofrequency

Study Results

Participant Flow

Recruitment Details	September 2017 to June 2020. Patients receiving treatment in Hospital Oost-Limburg, Genk, Belgium.
Pre-assignment Detail	Excluded patients (n=7): Chronic widespread pain (n=7)

Arm/Group Title	Conventional Radiofrequency (RF) Treatment
Arm/Group Description	All patients with chronic knee pain who qualify for a conventional radiofrequency (RF) treatment of the genicular nerves
Period Title: Follow-up at 6 Weeks
STARTED	61
COMPLETED	59
NOT COMPLETED	2
Period Title: Follow-up at 6 Weeks
STARTED	19
COMPLETED	17
NOT COMPLETED	2

Baseline Characteristics

Arm/Group Title	Degenerative Knee Pain	Persistent Post-surgical Pain (PPSP)	Total
Arm/Group Description	All patients with chronic knee pain who suffer from osteoarthritis (OA), soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.	Total of all reporting groups
Overall Participants	13	46	59
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	45.5 (15.9)	66.9 (13.9)	62.6 (16.9)
Sex: Female, Male (Count of Participants)
Female	7 53.8%	33 71.7%	40 67.8%
Male	6 46.2%	13 28.3%	19 32.2%
Race and Ethnicity Not Collected (Count of Participants)
Count of Participants [Participants]	0 0%
Index knee (participants) [Number]
Right	9 69.2%	18 39.1%	27 45.8%
Left	4 30.8%	28 60.9%	32 54.2%
Patients on strong opioids at baseline consultation (Count of Participants)
No use of strong opioids	10 76.9%	33 71.7%	43 72.9%
Use of strong opioids	3 23.1%	13 28.3%	16 27.1%
Mean NRS (± SD) prior to RF treatment (units on a scale.) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [units on a scale.]	7.8 (1.7)	7.3 (1.7)	7.4 (1.8)

Outcome Measures

1. Primary Outcome

Title	The Number of Patients Reaching Treatment Succes at 6 Weeks Defined as Global Perceived Effect (GPE) of ≥ 50% Compared to Baseline.
Description	Treatment success is defined as a global perceived effect (GPE) of at least 50% at measurement time point compared to baseline. Global perceived effect (GPE) scales are used as an overall outcome measure for patients with pain, as they may cover additional aspects to pain relief and physical function that are important to the individual. Patients are asked to response on the question of how the treatment influenced the pain symptoms. The patients were asked to expres their answer in percentage where 0 % ( no improvement) to 100 (total improvement, the symptoms are gone).
Time Frame	6 weeks after treatment

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	13	46
Count of Participants [Participants]	4 30.8%	15 32.6%

2. Secondary Outcome

Title	The Number of Participants With NRS Reduction ≥50% Compared to Baseline
Description	The numeric rating scale (NRS) is used to assess pain intensity varying from 0 (no pain) to 10 (intense pain). This scale was retrieved retrospectively out of the patient file. NRS reduction ≥50% is calculated using the NRS at 6 weeks compared to the NRS at baseline.
Time Frame	6 weeks after treatment

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	13	46
Count of Participants [Participants]	4 30.8%	9 19.6%

3. Secondary Outcome

Title	The Patient's NRS
Description	The numeric rating scale (NRS) is used to assess pain intensity varying from 0 (no pain) to 10 (intense pain). This scale will be asked telephonically to the patient.
Time Frame	after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Outcome Measure Data

Analysis Population Description

At the second time point: 4 patients with degenerative knee pain and 13 patients with PPSP were analysed.

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	13	46
Mean NRS at 6 weeks	5.6 (1.9)	7.3 (1.7)
Mean NRS in treatment success group	2.8 (1.5)	3.4 (1.7)
Mean NRS in treatment failure group	7.1 (2.4)	7.5 (1.5)
Mean NRS at the second time point	5.3 (2.0)	5.5 (1.9)
Mean NRS at the second time point in patients with GPE ≥50%	4.0 (0.0)	3.8 (2.2)
Mean NRS at the second time point in patients with GPE <50%	6.0 (2.0)	6.6 (0.8)

4. Secondary Outcome

Title	The Number of Patients With Subjective Increase in Physical Functioning at the Second Time Point
Description	The question 'Do you experience at the moment functional improvement in comparison with before the treatment?' is asked telephonically to the patient. The possible answers are 'no increase in physical functioning' and ' yes, there was an increase in physical funcitoning'. An increase in physical functioning is the best outcome.
Time Frame	after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Outcome Measure Data

Analysis Population Description

19 patients in total reached treatment succes at 6 weeks, 4 of which suffered from degenerative knee pain and 13 from PPSP. Two of these patients were excluded from analysis due to death and being mentally unable to fulfill the questionnaire. As a result 17 patients were analyzed for this endpoint.

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	4	13
Count of Participants [Participants]	1 7.7%	6 13%

5. Secondary Outcome

Title	The Number of Pariticipants Using Strong Opioids
Description	The change in use of strong opioids is retrieved retrospectively out of the patient file. The answer to the use of strong opioids is yes or no. No use of strong opioids is a better outcome.
Time Frame	6 weeks after treatment

Outcome Measure Data

Analysis Population Description

Strong opioid use is measured firstly in both subgroups and secondly in the treatment success and treatment failure group.

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	13	46
Patients on strong opioids	3 23.1%	8 17.4%
Patients on strong opioids in treatment success group	1 7.7%	3 6.5%
Patients on strong opioids in treatment failure group	2 15.4%	5 10.9%

6. Secondary Outcome

Title	Strong Opioid Use at the Second Time Point
Description	The change in use of strong opioids is asked telephonically to the patient.
Time Frame	after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Outcome Measure Data

Analysis Population Description

19 patients in total reached treatment succes at 6 weeks, 4 of which suffered from degenerative knee pain and 13 from PPSP. Two of these patients were excluded from analysis due to death and being mentally unable to fulfill the questionnaire. As a result 17 patients were analyzed for this endpoint.

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	4	13
Count of Participants [Participants]	1 7.7%	5 10.9%

7. Secondary Outcome

Title	The Number of Participants Reaching Treatment Success After Retrieval of the Informed Consent Defined as GPE of ≥ 50% Compared to Baseline.
Description	Treatment success is defined as a global perceived effect (GPE) of at least 50% at measurement time point compared to baseline. Global perceived effect (GPE) scales are used as an overall outcome measure for patients with pain, as they may cover additional aspects to pain relief and physical function that are important to the individual. Patients are asked to response on the question of how the treatment influenced the pain symptoms. The patients were asked to expres their answer in percentage where 0 % ( no improvement) to 100 (total improvement, the symptoms are gone).
Time Frame	after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Outcome Measure Data

Analysis Population Description

19 patients in total reached treatment succes at 6 weeks, 4 of which suffered from degenerative knee pain and 13 from PPSP. Two of these patients were excluded from analysis due to death and being mentally unable to fulfill the questionnaire. As a result 17 patients were analyzed for this endpoint.

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	4	13
Count of Participants [Participants]	2 15.4%	4 8.7%

8. Secondary Outcome

Title	Number of Participants With Post-treatment Complications
Description	Adverse events related to the conventional radiofrequency therapy will be assessed. This will be assessed retrospectively in the patient file according to the standard of care consultation at 6 weeks after treatment.
Time Frame	6 weeks after treatment.

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	13	46
Adverse events	3 23.1%	6 13%
Severe adverse events	0 0%	1 2.2%

9. Secondary Outcome

Title	Number of Participants With Post-treatment Complications
Description	Adverse events related to the conventional radiofrequency therapy will be assessed telephonically
Time Frame	after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Outcome Measure Data

Analysis Population Description

19 patients in total reached treatment succes at 6 weeks, 4 of which suffered from degenerative knee pain and 13 from PPSP. Two of these patients were excluded from analysis due to death and being mentally unable to fulfill the questionnaire. As a result 17 patients were analyzed for this endpoint.

Arm/Group Title	Degenerative Knee Pain	PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.	All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Measure Participants	4	13
Adverse events	0 0%	1 2.2%
Severe adverse events	0 0%	0 0%

Adverse Events

Time Frame	Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse Event Reporting Description	Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
Arm/Group Title	Degenerative Knee Pain		PPSP
Arm/Group Description	All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.		All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
All Cause Mortality
	Degenerative Knee Pain		PPSP
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	1/13 (7.7%)		0/46 (0%)
Serious Adverse Events
	Degenerative Knee Pain		PPSP
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/13 (0%)		1/46 (2.2%)
Nervous system disorders
Complex regional pain syndrome (CRPS)	0/13 (0%)	0	1/46 (2.2%)	1
Other (Not Including Serious) Adverse Events
	Degenerative Knee Pain		PPSP
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	3/13 (23.1%)		5/46 (10.9%)
Injury, poisoning and procedural complications
Self-limiting hematoma	1/13 (7.7%)	1	0/46 (0%)	0
Musculoskeletal and connective tissue disorders
Instability while walking	0/13 (0%)	0	1/46 (2.2%)	1
Increase in pain	0/13 (0%)	0	1/46 (2.2%)	1
Cracking of the joint	1/13 (7.7%)	1	0/46 (0%)	0
Nervous system disorders
Hypoesthesia	1/13 (7.7%)	1	3/46 (6.5%)	3

Limitations/Caveats

One of the limitations of this study is inherent to its retrospective nature. A second limitation is that comparison with previous studies is difficult due to the use of ultrasound as guidance for the procedure as most of the studies use fluoroscopy-guided RF. Another limitation concerns the subgroup analysis of degenerative knee pain. These results need to be interpreted with caution due to the small number of patients included in this group.

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.