Chronic Knee Pain
Conditions
Keywords
Conventional radiofrequency
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.
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.
Interventions
None listed
Sponsors
Ziekenhuis Oost-Limburg
Study design
Observational model
COHORT
Time perspective
RETROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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. |
| 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. |
| 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. |
| 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. |
| 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). |
| 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. |
| 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. |
Countries
Belgium
Participant flow
Recruitment details
September 2017 to June 2020. Patients receiving treatment in Hospital Oost-Limburg, Genk, Belgium.
Pre-assignment details
Excluded patients (n=7): Chronic widespread pain (n=7)
Participants by arm
| Arm | Count |
|---|---|
| Degenerative Knee Pain All patients with chronic knee pain who suffer from osteoarthritis (OA), soft tissue (e.g., ligament) disease and posttraumatic pain. | 13 |
| Persistent Post-surgical Pain (PPSP) All patients with chronic knee pain who suffer from PPSP after all types orthopaedic surgeries of the knee. | 46 |
| Total | 59 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| 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
| Characteristic | Degenerative Knee Pain | Persistent Post-surgical Pain (PPSP) | Total |
|---|---|---|---|
| Age, Continuous | 45.5 years STANDARD_DEVIATION 15.9 | 66.9 years STANDARD_DEVIATION 13.9 | 62.6 years STANDARD_DEVIATION 16.9 |
| Index knee Left | 4 participants | 28 participants | 32 participants |
| Index knee Right | 9 participants | 18 participants | 27 participants |
| Mean NRS (± SD) prior to RF treatment | 7.8 units on a scale. STANDARD_DEVIATION 1.7 | 7.3 units on a scale. STANDARD_DEVIATION 1.7 | 7.4 units on a scale. STANDARD_DEVIATION 1.8 |
| Patients on strong opioids at baseline consultation No use of strong opioids | 10 Participants | 33 Participants | 43 Participants |
| Patients on strong opioids at baseline consultation Use of strong opioids | 3 Participants | 13 Participants | 16 Participants |
| Race and Ethnicity Not Collected | — | — | 0 Participants |
| Sex: Female, Male Female | 7 Participants | 33 Participants | 40 Participants |
| Sex: Female, Male Male | 6 Participants | 13 Participants | 19 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 1 / 13 | 0 / 46 |
| other Total, other adverse events | 3 / 13 | 5 / 46 |
| serious Total, serious adverse events | 0 / 13 | 1 / 46 |
Outcome results
Primary
The Number of Patients Reaching Treatment Succes at 6 Weeks Defined as Global Perceived Effect (GPE) of ≥ 50% Compared to Baseline.
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
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Degenerative Knee Pain | The Number of Patients Reaching Treatment Succes at 6 Weeks Defined as Global Perceived Effect (GPE) of ≥ 50% Compared to Baseline. | 4 Participants |
| PPSP | The Number of Patients Reaching Treatment Succes at 6 Weeks Defined as Global Perceived Effect (GPE) of ≥ 50% Compared to Baseline. | 15 Participants |
Secondary
Number of Participants With Post-treatment Complications
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
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.
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Degenerative Knee Pain | Number of Participants With Post-treatment Complications | Adverse events | 0 Participants |
| Degenerative Knee Pain | Number of Participants With Post-treatment Complications | Severe adverse events | 0 Participants |
| PPSP | Number of Participants With Post-treatment Complications | Adverse events | 1 Participants |
| PPSP | Number of Participants With Post-treatment Complications | Severe adverse events | 0 Participants |
Secondary
Number of Participants With Post-treatment Complications
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.
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Degenerative Knee Pain | Number of Participants With Post-treatment Complications | Adverse events | 3 Participants |
| Degenerative Knee Pain | Number of Participants With Post-treatment Complications | Severe adverse events | 0 Participants |
| PPSP | Number of Participants With Post-treatment Complications | Adverse events | 6 Participants |
| PPSP | Number of Participants With Post-treatment Complications | Severe adverse events | 1 Participants |
Secondary
Strong Opioid Use at the Second Time Point
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
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.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Degenerative Knee Pain | Strong Opioid Use at the Second Time Point | 1 Participants |
| PPSP | Strong Opioid Use at the Second Time Point | 5 Participants |
Secondary
The Number of Pariticipants Using Strong Opioids
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
Population: Strong opioid use is measured firstly in both subgroups and secondly in the treatment success and treatment failure group.
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Degenerative Knee Pain | The Number of Pariticipants Using Strong Opioids | Patients on strong opioids | 3 Participants |
| Degenerative Knee Pain | The Number of Pariticipants Using Strong Opioids | Patients on strong opioids in treatment success group | 1 Participants |
| Degenerative Knee Pain | The Number of Pariticipants Using Strong Opioids | Patients on strong opioids in treatment failure group | 2 Participants |
| PPSP | The Number of Pariticipants Using Strong Opioids | Patients on strong opioids | 8 Participants |
| PPSP | The Number of Pariticipants Using Strong Opioids | Patients on strong opioids in treatment success group | 3 Participants |
| PPSP | The Number of Pariticipants Using Strong Opioids | Patients on strong opioids in treatment failure group | 5 Participants |
Secondary
The Number of Participants Reaching Treatment Success After Retrieval of the Informed Consent Defined as GPE of ≥ 50% Compared to Baseline.
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
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.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Degenerative Knee Pain | The Number of Participants Reaching Treatment Success After Retrieval of the Informed Consent Defined as GPE of ≥ 50% Compared to Baseline. | 2 Participants |
| PPSP | The Number of Participants Reaching Treatment Success After Retrieval of the Informed Consent Defined as GPE of ≥ 50% Compared to Baseline. | 4 Participants |
Secondary
The Number of Participants With NRS Reduction ≥50% Compared to Baseline
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
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Degenerative Knee Pain | The Number of Participants With NRS Reduction ≥50% Compared to Baseline | 4 Participants |
| PPSP | The Number of Participants With NRS Reduction ≥50% Compared to Baseline | 9 Participants |
Secondary
The Number of Patients With Subjective Increase in Physical Functioning at the Second Time Point
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
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.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Degenerative Knee Pain | The Number of Patients With Subjective Increase in Physical Functioning at the Second Time Point | 1 Participants |
| PPSP | The Number of Patients With Subjective Increase in Physical Functioning at the Second Time Point | 6 Participants |
Secondary
The Patient's NRS
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
Population: At the second time point: 4 patients with degenerative knee pain and 13 patients with PPSP were analysed.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Degenerative Knee Pain | The Patient's NRS | Mean NRS at 6 weeks | 5.6 score on a scale | Standard Deviation 1.9 |
| Degenerative Knee Pain | The Patient's NRS | Mean NRS in treatment success group | 2.8 score on a scale | Standard Deviation 1.5 |
| Degenerative Knee Pain | The Patient's NRS | Mean NRS in treatment failure group | 7.1 score on a scale | Standard Deviation 2.4 |
| Degenerative Knee Pain | The Patient's NRS | Mean NRS at the second time point | 5.3 score on a scale | Standard Deviation 2 |
| Degenerative Knee Pain | 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 |
| Degenerative Knee Pain | 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 |
| PPSP | The Patient's NRS | Mean NRS at the second time point in patients with GPE ≥50% | 3.8 score on a scale | Standard Deviation 2.2 |
| PPSP | The Patient's NRS | Mean NRS at 6 weeks | 7.3 score on a scale | Standard Deviation 1.7 |
| PPSP | The Patient's NRS | Mean NRS at the second time point | 5.5 score on a scale | Standard Deviation 1.9 |
| PPSP | The Patient's NRS | Mean NRS in treatment success group | 3.4 score on a scale | Standard Deviation 1.7 |
| PPSP | The Patient's NRS | Mean NRS at the second time point in patients with GPE <50% | 6.6 score on a scale | Standard Deviation 0.8 |
| PPSP | The Patient's NRS | Mean NRS in treatment failure group | 7.5 score on a scale | Standard Deviation 1.5 |