Trial Outcomes & Findings for Patients With Chronic Knee Pain Treated With Conventional Radiofrequency of the Genicular Nerves (NCT NCT04234984)

NCT ID: NCT04234984

Last Updated: 2022-06-14

Results Overview

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).

Recruitment status

COMPLETED

Target enrollment

66 participants

Primary outcome timeframe

6 weeks after treatment

Results posted on

2022-06-14

Participant Flow

September 2017 to June 2020. Patients receiving treatment in Hospital Oost-Limburg, Genk, Belgium.

Excluded patients (n=7): Chronic widespread pain (n=7)

Participant milestones

Participant milestones
Measure
Conventional Radiofrequency (RF) Treatment
All patients with chronic knee pain who qualify for a conventional radiofrequency (RF) treatment of the genicular nerves
Follow-up at 6 Weeks
STARTED
61
Follow-up at 6 Weeks
COMPLETED
59
Follow-up at 6 Weeks
NOT COMPLETED
2
Follow-up at the Second Time Point
STARTED
19
Follow-up at the Second Time Point
COMPLETED
17
Follow-up at the Second Time Point
NOT COMPLETED
2

Reasons for withdrawal

Reasons for withdrawal
Measure
Conventional Radiofrequency (RF) Treatment
All patients with chronic knee pain who qualify for a conventional radiofrequency (RF) treatment of the genicular nerves
Follow-up at 6 Weeks
Lost to Follow-up
2
Follow-up at the Second Time Point
Death
1
Follow-up at the Second Time Point
Mentally unable to fill in the questionnaire
1

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Degenerative Knee Pain
n=13 Participants
All patients with chronic knee pain who suffer from osteoarthritis (OA), soft tissue (e.g., ligament) disease and posttraumatic pain.
Persistent Post-surgical Pain (PPSP)
n=46 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Total
n=59 Participants
Total of all reporting groups
Age, Continuous
45.5 years
STANDARD_DEVIATION 15.9 • n=13 Participants
66.9 years
STANDARD_DEVIATION 13.9 • n=46 Participants
62.6 years
STANDARD_DEVIATION 16.9 • n=59 Participants
Sex: Female, Male
Female
7 Participants
n=13 Participants
33 Participants
n=46 Participants
40 Participants
n=59 Participants
Sex: Female, Male
Male
6 Participants
n=13 Participants
13 Participants
n=46 Participants
19 Participants
n=59 Participants
Race and Ethnicity Not Collected
0 Participants
Race and Ethnicity were not collected from any participant.
Index knee
Right
9 participants
n=13 Participants
18 participants
n=46 Participants
27 participants
n=59 Participants
Index knee
Left
4 participants
n=13 Participants
28 participants
n=46 Participants
32 participants
n=59 Participants
Patients on strong opioids at baseline consultation
No use of strong opioids
10 Participants
n=13 Participants
33 Participants
n=46 Participants
43 Participants
n=59 Participants
Patients on strong opioids at baseline consultation
Use of strong opioids
3 Participants
n=13 Participants
13 Participants
n=46 Participants
16 Participants
n=59 Participants
Mean NRS (± SD) prior to RF treatment
7.8 units on a scale.
STANDARD_DEVIATION 1.7 • n=13 Participants
7.3 units on a scale.
STANDARD_DEVIATION 1.7 • n=46 Participants
7.4 units on a scale.
STANDARD_DEVIATION 1.8 • n=59 Participants

PRIMARY outcome

Timeframe: 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).

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=13 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
The Number of Patients Reaching Treatment Succes at 6 Weeks Defined as Global Perceived Effect (GPE) of ≥ 50% Compared to Baseline.
4 Participants
15 Participants

SECONDARY outcome

Timeframe: 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.

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=13 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
The Number of Participants With NRS Reduction ≥50% Compared to Baseline
4 Participants
9 Participants

SECONDARY outcome

Timeframe: after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

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

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.

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=13 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
The Patient's NRS
Mean NRS at 6 weeks
5.6 score on a scale
Standard Deviation 1.9
7.3 score on a scale
Standard Deviation 1.7
The Patient's NRS
Mean NRS in treatment success group
2.8 score on a scale
Standard Deviation 1.5
3.4 score on a scale
Standard Deviation 1.7
The Patient's NRS
Mean NRS in treatment failure group
7.1 score on a scale
Standard Deviation 2.4
7.5 score on a scale
Standard Deviation 1.5
The Patient's NRS
Mean NRS at the second time point
5.3 score on a scale
Standard Deviation 2.0
5.5 score on a scale
Standard Deviation 1.9
The Patient's NRS
Mean NRS at the second time point in patients with GPE ≥50%
4.0 score on a scale
Standard Deviation 0.0
3.8 score on a scale
Standard Deviation 2.2
The Patient's NRS
Mean NRS at the second time point in patients with GPE <50%
6.0 score on a scale
Standard Deviation 2.0
6.6 score on a scale
Standard Deviation 0.8

SECONDARY outcome

Timeframe: after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Population: 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.

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.

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=4 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=13 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
The Number of Patients With Subjective Increase in Physical Functioning at the Second Time Point
1 Participants
6 Participants

SECONDARY outcome

Timeframe: 6 weeks after treatment

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

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.

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=13 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
The Number of Pariticipants Using Strong Opioids
Patients on strong opioids
3 Participants
8 Participants
The Number of Pariticipants Using Strong Opioids
Patients on strong opioids in treatment success group
1 Participants
3 Participants
The Number of Pariticipants Using Strong Opioids
Patients on strong opioids in treatment failure group
2 Participants
5 Participants

SECONDARY outcome

Timeframe: after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Population: 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.

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

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=4 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=13 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Strong Opioid Use at the Second Time Point
1 Participants
5 Participants

SECONDARY outcome

Timeframe: after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Population: 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.

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).

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=4 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=13 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
The Number of Participants Reaching Treatment Success After Retrieval of the Informed Consent Defined as GPE of ≥ 50% Compared to Baseline.
2 Participants
4 Participants

SECONDARY outcome

Timeframe: 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.

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=13 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Number of Participants With Post-treatment Complications
Adverse events
3 Participants
6 Participants
Number of Participants With Post-treatment Complications
Severe adverse events
0 Participants
1 Participants

SECONDARY outcome

Timeframe: after retrieval of informed consent, ranging from 6 weeks to 2.5 years after the procedure

Population: 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.

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

Outcome measures

Outcome measures
Measure
Degenerative Knee Pain
n=4 Participants
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=13 Participants
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Number of Participants With Post-treatment Complications
Adverse events
0 Participants
1 Participants
Number of Participants With Post-treatment Complications
Severe adverse events
0 Participants
0 Participants

Adverse Events

Degenerative Knee Pain

Serious events: 0 serious events
Other events: 3 other events
Deaths: 1 deaths

PPSP

Serious events: 1 serious events
Other events: 5 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Degenerative Knee Pain
n=13 participants at risk
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 participants at risk
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Nervous system disorders
Complex regional pain syndrome (CRPS)
0.00%
0/13 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
2.2%
1/46 • Number of events 1 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.

Other adverse events

Other adverse events
Measure
Degenerative Knee Pain
n=13 participants at risk
All patients with chronic knee pain who suffer from OA, soft tissue (e.g., ligament) disease and posttraumatic pain.
PPSP
n=46 participants at risk
All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee.
Musculoskeletal and connective tissue disorders
Instability while walking
0.00%
0/13 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
2.2%
1/46 • Number of events 1 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
Nervous system disorders
Hypoesthesia
7.7%
1/13 • Number of events 1 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
6.5%
3/46 • Number of events 3 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
Musculoskeletal and connective tissue disorders
Increase in pain
0.00%
0/13 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
2.2%
1/46 • Number of events 1 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
Injury, poisoning and procedural complications
Self-limiting hematoma
7.7%
1/13 • Number of events 1 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
0.00%
0/46 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
Musculoskeletal and connective tissue disorders
Cracking of the joint
7.7%
1/13 • Number of events 1 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.
0.00%
0/46 • Collection of data happened in a time period that was different for every patient varying from 6 weeks to 2.5 years
Adverse events were defined as any undesirable experience occurring to a subject during the study that is related to the investigational intervention.

Additional Information

Prof. Dr. Jan Van Zundert

Department of Anaesthesiology & Pain Medicine, Maastricht University Medical Centre, Postbus 5800, 6202 AZ Maastricht, The Netherlands.

Phone: (+32) 475687657

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place