Can Patient Expectations Influence Pain Reduction After Epidural Injections in Patients With Low Back Pain?

Study Overview
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Brief Summary
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Investigators hypothesize that patients with higher expectations regarding their epidural injection experience a higher pain reduction of their lower back pain and/or leg pain after an epidural injection. Patients' expectations of an epidural injection can influence their level of pain reduction. The primary objective of this study is to investigate the prognostic significance of patient expectations on pain reduction after epidural injections ('expected benefits', see under) in patients with low back pain and/or leg pain. Investigators furthermore hypothesize that patients that have a higher match between their expectations of improvement and actual improvement are more satisfied. A secondary objective of this study is to investigate the prognostic significance of a high match between expectations of improvement and actual improvement on patient satisfaction of the treatment.

Detailed Description
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Chronic low back pain (with or without lower extremity pain) is extremely common problem in primary care and the leading cause worldwide for disability. Approximately 70 to 85% of the western population will develop low back pain at least once during their lifetime. Low back pain is pain, muscle tension, or stiffness localized below the costal margin and above the inferior gluteal folds, with or without sciatica, and is defined as chronic when it persists for 12 weeks or more. The burden on the economy of low back pain were estimated at €2.6 billion and the direct medical costs at 6.1% of the total healthcare expenditure in Switzerland. Multiple modalities of treatments are utilized in managing chronic low back pain including analgesics, physiotherapy, injections, acupuncture, or surgery. Intralaminar and transforaminal lumbar epidural injections of corticosteroids have shown to be effective in patients with chronic low back pain and or leg pain. Several studies demonstrated how patients' expectations are important predictors of the postsurgical health outcome. Patients' expectations are frequently studied as prognostic factors in knee and hip arthroplasty. It was shown that patients undergoing elective orthopaedic surgery whose expectations were fulfilled were found to be more satisfied with the overall treatment as compared to those whose expectations were not fulfilled. Furthermore, it was found that there is a robust small positive association between patients' positive preoperative expectations and better patient-reported postoperative outcomes. Investigators hypothesize that patient expectations of the pain treatment is also an important predictor of the pain reduction after epidural injections in patients with low back pain and/or leg pain. Therefore, the aim of this study is to investigate the prognostic significance of patient expectations on pain reduction after epidural injections in patients with low back pain and/or leg pain.

Official Title
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Can Patient Expectations Influence Pain Reduction After Epidural Injections in Patients With Low Back Pain? An Observational Cohort Study

Conditions
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Expectations, Back Pain, Back Pain Lower Back Chronic, Satisfaction, Patient, Injections, Epidural, Injections, Periradicular, Pain, Back

Intervention / Treatment
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* Procedure: Epidural Injection
* Procedure: Periradicular Injection


Participation Criteria
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Eligibility Criteria
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Inclusion criteria Subjects fulfilling all of the following inclusion criteria are eligible for the investigation: Age > 18 years old. Patients treated with a fluoroscopic guided lumbar epidural injection (transforaminal/translaminar/caudal) for back and/or leg pain Exclusion criteria The presence of any one of the following exclusion criteria will lead to the exclusion of the subject patients who did not complete the questionnaires patient did not sign the general consent form (EOC_M-AFRI-001/A)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| New patient with lower back pain<br> | Procedure: Epidural Injection<br>* patient receives an epidural injection due to lower back pain<br>Procedure: Periradicular Injection<br>* patient receives a periradicular injection due to lower back pain<br>|
| known patient with lower back pain<br> | Procedure: Epidural Injection<br>* patient receives an epidural injection due to lower back pain<br>Procedure: Periradicular Injection<br>* patient receives a periradicular injection due to lower back pain<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction of the average pain severity | The reduction of the average pain severity score of the Brief Pain Inventory Short form [Time Frame: 10 days after injection in comparison to baseline]. Brief Pain Inventory (BPI) Short form will be used to assess pain intensity after lumbar epidural injection. BPI assess for pain and its scale is measured between 0 - 10, where '0' indicates no pain and '10' indicates severe pain in the last 24 hours. A decrease in the BPI score of 2 or more from the baseline score is considered clinically significant and indicates an improvement in severity of the patient's pain.15 We will examine the prognostic significance of patient expectations ('expected benefits', see under) on pain reduction after epidural injections in patients with low back pain and/or leg pain. | 10 days after injection | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brief Pain Inventory Short form: average pain interference score | BPI average pain interference score assesses the interference the pain has on the patient's functioning. BPI interference is measured between 0-10, where '0' indicates no interference and '10' indicates severe interference with functioning | 10 days after injection | 
| The reduction of the immediate pain severity score of the Brief Pain Inventory Short form | Again the scale is measured between 0 - 10, where '0' indicates no pain and '10' indicates severe pain. A decrease in the BPI score of 2 or more from the baseline score is considered clinically significant and indicates an improvement in severity of the patient's pain | 1 hour after injection | 
| Patient Global Impression of Change (PGIC) | The PGIC rating is increasingly being used for determining clinically important change in measures such as ratings of pain. This scale is designed to quantify patient's improvement or deterioration over time, usually either to determine the effect of an intervention or to chart the clinical course of a condition. The scales ask that a person assess his or her current health status, recall that status at a previous time-point, and then calculate the difference between the two. | 10 days after injection | 
| Patients' satisfaction | o This scale is designed to quantify patient's satisfaction with the treatment. Patients will be asked to define the one number that best shows how satisfied they are with the results of their pain treatment. Its scale is measured between 0 - 10, where '0' indicates extremely dissatisfied and '10' indicates extremely satisfied. | 10 days after injection | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Influence of Expectations on Outcome, Epidural Injections, Periradicular Injections, Expectations, Back Pain