Pain Sensitization and the Risk of Poor Outcome Following Physiotherapy for Knee Osteoarthritis: A Protocol for a Prospective Cohort Study
试验速览
- 阶段
- 不适用
- 入组人数
- 140
- 试验地点
- 3
- 主要终点
- Change in response to physiotherapy as measured by the pain and function sub-scales of Western Ontario and McMasters University Score Osteoarthritis Index (WOMAC) and patient's global rating of change.
研究概览
简要总结
Pain is the dominant symptom of knee osteoarthritis and recent evidence suggests factors outside of local joint pathology, such as pain sensitization, can contribute significantly to the pain experience. It is unknown how pain sensitization influences outcomes from commonly employed interventions such as physiotherapy.
The aims of this study are, firstly to identify people with knee OA who display signs and symptoms associated with pain sensitization using clinical tools and quantitative sensory testing. Secondly, we will investigate if indications of pain sensitization at baseline are associated with poor outcome following physiotherapy.
Methods and analysis:
This is a multi-centre prospective cohort study with 140 participants. Eligible patients with moderate/severe symptomatic knee osteoarthritis will be identified at hospital outpatient clinics. A baseline assessment will provide a comprehensive description of the somatosensory characteristics of each participant by means of clinical examination, quantitative sensory testing and validated questionnaires measuring pain and functional capacity. Participants will then undergo physiotherapy treatment, in line with current clinical guidelines. Follow-up post physiotherapy treatment (estimated to be at 3 months) will assess pain, disability (sub-scales of Western Ontario and McMasters University Score Osteoarthritis Index) and participants' global rating of change. These primary outcome measures will dichotomise participants into treatment 'responders' and 'non-responders' according to the Osteoarthritis Research Society International (OARSI) treatment responder criteria.
For data analysis results from pressure pain thresholds, temporal summation and conditioned pain modulation will create a composite score of pain sensitization. Logistic regression will explore the relationship between response to physiotherapy and pain sensitization at baseline while accounting for various cofounders.
详细描述
BACKGROUND
The pathophysiology of knee OA pain is complex. Altered processing of nociceptive inputs at spinal and higher brain centers may help explain discrepancies between pain severity and pathological abnormalities in OA. Central sensitization is described as an increased responsiveness of nociceptive neurons at spinal and supraspinal levels to normal or sub-threshold afferent input leading to hyperalgesia. It may also include dysfunction of endogenous pain control systems. Furthermore, peripheral pro-inflammatory mediators and neuropeptides in knee OA can sensitize nociceptors, lowering their threshold for activation. This increased responsiveness of peripheral nociceptors is referred to as peripheral sensitization.
Both peripheral and central nervous system sensitization, clinically referred to as pain sensitization can result can be an enhanced, persistent and more widespread pain response. Recent studies have found the presence of increased pain sensitivity at remote sites, enhanced temporal summation and hypersensitivity to various stimuli to be associated with reports of more severe knee pain symptoms. These studies are cross-sectional and although they link signs of sensitization with greater levels of pain and disability they cannot infer causality.
There is some evidence to suggest increased pain sensitivity negatively affects treatment outcomes. In painful musculoskeletal conditions such as shoulder impingement and lateral epicondylalgia widespread pressure pain sensitivity and thermal hyperalgesia, have been linked with a poorer prognosis. Surgical outcomes for knee osteoarthritis may also be affected with the presence of increased pain sensitivity prior to total knee replacement associated with more persistent pain after surgery.
Physiotherapy is a widely recommended conservative management approach. Studies of prognosis in knee OA have focused on demographic and psychological variable, few studies have focused on factors relating to abnormal pain processing. No longitudinal studies have explored prognostic factors relating to pain sensitization and outcome following physiotherapy. In whiplash associated disorders the presence of sensory hypersensitivity and cold hyperalgesia has been shown to reduce the likelihood of a positive response to physiotherapy treatment. Thus it is conceivable, but currently unproven, that knee OA patients with evidence of pain sensitization have poorer outcomes following physiotherapy.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 50 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Knee osteoarthritis diagnosed by American College of Rheumatology clinical criteria
- •Knee pain must be the primary musculoskeletal complaint participant is seeking treatment for
- •Pain duration greater than 3 months
- •Pain severity ≥ 5/10 on Numerical Rating Scale
- •Willing to abstain from simple analgesics and NSAIDs for 24 hours prior to testing
- •Willing and able to give full consent
排除标准
- •Lumbar or cervical radiculopathy,
- •Systematic inflammatory disease,
- •Positive screen for diabetic neuropathy
- •Past medical history
- •Previous surgery or disease of the peripheral or central nervous system,
- •Sensory loss secondary to chemotherapy or radiotherapy
- •Fibromyalgia
- •Chronic fatigue syndrome
- •Cognitive or psychiatric disorder interfering with ability to cooperate with assessment
- •Injection or physiotherapy treatment for knee joint within previous 3 months
- •Taking anti-depressant or anti-convulsant medication
结局指标
主要结局
Change in response to physiotherapy as measured by the pain and function sub-scales of Western Ontario and McMasters University Score Osteoarthritis Index (WOMAC) and patient's global rating of change.
时间窗: Baseline & at 3 months (estimated time point for physiotherapy treatment completion)
These 3 outcome measures will gather data that will be applied to a set of treatment responder criteria by the Outcome Measures in Rheumatology - Osteoarthritis Research Society International (OMERACT-OARSI) to determine a positive response to physiotherapy or a 'treatment responder'
次要结局
- EQ-5D 5L(Baseline)
- Overweight/Obesity(Baseline)
- Quantitative sensory testing (pressure pain thresholds, temporal summation, conditioned pain modulation, mechanical detection thresholds)(Baseline)
- Modified PainDETECT(Baseline)
- Manual tender point count(Baseline)
- Self Administered Comorbidity Questionnaire(Baseline)
- Centre for Epidemiologic Studies Depression Scale (CES-D)(Baseline)
- Patient adherence monitored over the course of physiotherapy treatment (Sports Injury Rehabilitation Adherence Scale (SIRAS) and Home Exercise Compliance Assessment (HECA) )(Recorded at each physiotherapy appointment (approx 6 times between 0 and 3 months))
- Central Sensitization Inventory(Baseline)
- Widespread pain(Baseline)
- Change in medication use and use of co-interventions(At 3 months (estimated time point for physiotherapy treatment completion))
- Change in knee pain and disability at 6 months(Baseline and at 6 months)