Chronic Opioid Use, Chronic Post Surgical Pain, ERAS, Functional Recovery, Inthrathecal Morfine, Knee Arthroplasty
Conditions
Keywords
ERAS, CPSP, Functional recovery, Knee Arthroplasty
Brief summary
The goal of this study is to learn about pain after knee replacement surgery. The surgery uses a fast-recovery program called Enhanced Recovery After Surgery (ERAS). The main questions are: How many participants still have pain three months after surgery? How severe is the pain? How many participants still use strong pain medication (opioids)? Participants are adults undergoing knee replacement surgery at UZ Gent and following the ERAS program. Researchers will collect information on pain and recovery before surgery and for up to three months afterward. Participants will answer simple questions about their pain and daily activities. This study will help researchers understand post-surgical recovery and may help improve pain care in the future.
Detailed description
This prospective observational cohort study evaluates perioperative pain management and recovery outcomes in adult patients undergoing primary knee replacement surgery within an Enhanced Recovery After Surgery (ERAS), or fast-track, pathway at UZ Gent. Knee arthroplasty is an established surgical intervention for patients with advanced joint disease, with the aim of improving mobility and reducing pain. The ERAS pathway integrates standardized perioperative care elements, including optimized anesthesia, multimodal analgesia, early mobilization, and reduced length of hospital stay. While ERAS protocols have demonstrated benefits regarding recovery and hospital discharge, the effect of these pathways on persistent postoperative pain and opioid use requires further evaluation. Persistent pain after knee replacement surgery remains an important clinical outcome. A proportion of patients experience ongoing pain or functional limitations despite technically successful surgery. Patients included in this study will undergo knee replacement surgery according to the institutional ERAS protocol. The protocol includes preoperative assessment, standardized perioperative care, and early postoperative mobilization. Suitability for the ERAS pathway is evaluated during the preoperative anesthesia consultation. Any deviations from the standardized pathway, including changes in perioperative management or rehabilitation, will be documented together with the reason for the deviation. Patients undergoing knee replacement surgery according to the ERAS pathway will be followed prospectively from the preoperative assessment until three months after surgery. Data collected will include perioperative characteristics, pain scores, functional outcomes, neuropathic pain features, opioid use, and relevant clinical variables. Clinical data will be collected prospectively from the preoperative period until three months after surgery. Pain outcomes will be assessed at predefined time points using validated pain assessment tools. Information regarding pain intensity, functional recovery, neuropathic pain characteristics, and opioid medication use will be collected. Additional perioperative variables, including patient characteristics, anesthesia technique, surgical technique, and relevant medical history, will be recorded. The study population consists of approximately 120 patients undergoing primary elective knee arthroplasty over a one-year inclusion period. Patients who are not considered suitable for the standardized ERAS approach because of relevant medical, neurological, physical, cognitive, surgical, or rehabilitation-related factors will not be included. The collected data will be analyzed to describe the occurrence and characteristics of persistent postoperative pain after knee replacement surgery within an ERAS pathway. Descriptive analyses will summarize patient characteristics, pain outcomes, opioid use, and recovery measures. Exploratory analyses will evaluate potential associations between perioperative factors and persistent postoperative pain. As ERAS has become the standard of care at the institution, comparison with a conventional-care control group is not planned. Instead, findings from this cohort will be interpreted in relation to previously published data from conventional perioperative care pathways. This study aims to provide clinical insight into pain recovery after knee arthroplasty within an ERAS program and may contribute to improving postoperative pain management and patient follow-up strategies.
Interventions
None listed
Sponsors
University Hospital, Ghent
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* All patients suitable for a standardized approach to the primary elective knee arthroplasty surgery and recovery period.
Exclusion criteria
* Significant comorbidities that may cause complications during the operation or the recovery period (e.g., heart and lung diseases, severe kidney disease, severe overweight). * Severe neurological, physical, mental, and/or cognitive conditions that may complicate rehabilitation (e.g., inability to understand or follow postoperative instructions). * Active infections or septic arthritis. * Specific surgical obstacles such as revision surgery, extensive previous joint surgery, severe limitations in movement, severe instability, or marked abnormalities.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Chronic postoperative pain (CPSP) at three months after knee arthroplasty | Three months after knee arthroplasty | Pain intensity will be assessed using the Numeric Rating Scale (NRS) during movement. CPSP will be defined as an NRS score ≥4 at three months postoperatively. Severe chronic postoperative pain will be defined as an NRS score ≥6. Unit of Measure: Points on an 0-10 Numeric Rating Scale. |
| Functional recovery at 3 months after knee replacement | 3 months postoperatively | Functional recovery will be assessed using the Oxford Knee Score (OKS). A score ≤14 indicates a poor functional outcome related to knee pain. Unit of Measure: Points on the Oxford Knee Score (0-48) |
| Neuropathic pain characteristics at 3 months | 3 months postoperatively | Neuropathic pain features will be evaluated using the DN4 questionnaire. A DN4 score ≥4 is considered suggestive of neuropathic pain. Unit of Measure: Points on the DN4 questionnaire (0-10). |
| Postoperative opioid use at 3 months | 3 months postoperatively | Postoperative opioid use will be assessed by recording whether participants use opioid medication and, if applicable, the amount of opioid medication used. Unit: Number of participants using opioids (yes/no) and/or morphine milligram equivalents (MME). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Postoperative pain intensity during hospital stay after knee arthroplasty | Postoperative day 1 and day 2 after knee arthroplasty | Pain intensity will be assessed using the Numeric Rating Scale (NRS) at rest and during movement. Weighted average NRS pain scores will be calculated for postoperative day 1 and day 2. Unit of Measure: Points on an 0-10 Numeric Rating Scale. |
| Preoperative and discharge pain intensity after knee arthroplasty | Preoperatively and at postoperative day 1-2-3-4 (at hospital discharge) | Pain intensity will be assessed using the Numeric Rating Scale (NRS) at rest and during movement before surgery and at hospital discharge. Unit of Measure: Points on an 0-10 Numeric Rating Scale. |
| Opioid consumption during the perioperative period | Perioperative period through postoperative day 1-2-3 (at hospital discharge) | Opioid pain medication use will be recorded before surgery and during hospital stay. Opioid consumption will be converted into morphine milligram equivalents (MME) and reported as a weighted average per day. Unit of Measure: Morphine milligram equivalents (MME/day). |
| Surgical complications after knee arthroplasty | From surgery until three months postoperatively | Surgical complications will be identified from medical records and surgical documentation. Unit of Measure: Number and percentage of participants with complications. |
| Length of hospital stay after knee arthroplasty | Postoperative day 1-2-3-4 | Hospital stay will be calculated from the day of surgery until discharge. Unit of Measure: Days. |
Countries
Belgium
Contacts
STUDY_CHAIRPatrick Wouters, Prof. Dr.
University Hospital, Ghent
Outcome results
None listed