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It is a commonly held belief that acute low back pain (LBP) resolves within 4 to 6 weeks for most individuals
(75%-90%). 이런 긍정적 기대는 false confidence. 그 이유는 symptomatic approach(bed rest and medication) 또는 non-management approach로 방치되어 nature run its course.
Von Korff et al demonstrated in a non-occupational setting that after 1 month only 30% of neck and low back pain patients had achieved pain-free status, and after 1 year 50% still reported recurrent or persistent pain (117).
Even though only a small percentage (7%) of individuals with acute LBP have chronic unremitting pain and disability, this group accounts for the majority of the costs (11,107).
Risk Factors of Chronicity
- 요통을 만성화시키는 risk factor와 관련된 개념이 yellow flags임
- red flags은 cancer등 심각한 질환
Four Main Factors that Influence Chronic Disability
Psycho-Social and Other Factors
• severe radiating lower limb pain
• at least moderate physical disability (Oswestry)
• psychological distress
• the need to lift for at least three-fourths of the day
• a workplace unable to provide light duties on return to work
Three-phase model of low back pain natural history
Fear-Avoidance Beliefs
One of the major goals of care is to reduce activity intolerances associated with pain (2,81). Thus, the cognitive association of activity with pain or anticipation of pain is an important psychological construct (14,24,95,101). In fact, the belief that an activity will be painful has been shown to be more predictive of physical performance than purely nociceptive factors(68,69). - 움직임 활동이 통증을 유발할 것이라는 믿음은 순수하게 손상때문에 전달되는 유해자극요소보다 신체활동의 예측인자가 되어왔다.
Anxious patients predict pain sooner during the performance of physical tasks such as range of motion (ROM) or straight leg raise tests(14,15,24). Council et aJ. documented substantial correlations between pain expectancies and self-rated
physical disability with the performance of simple motor tasks (22). It is important to distinguish those factors that are
associated with chronic pain from those that predict it.
For instance, Ciccione showed that depression, somatization, and current pain ratings combined to explain 34% of the variance in work disability in a chronic group (15). However, these factors explained only 8% of the variance in an acute sample!
- 우울감, 신체화장애, 통증 재발 등은만성통증과 disability를 34%밖에 설명못하고, 급성통증에서는 8%밖에 설명 못함
More significant is the finding that pain expectancies accounted for 33% of the variance in acute subjects (P < 0.001) (15). Fritz et al. has also confirmed that initial fear-avoidance beliefs were significant predictors of subacute status at 4 weeks independent of pain intensity, physical impairment, disability, or therapy received (34,35).
- 좀더 중요한 인자는 급성통증환자에게서는 잘못된 통증의 기대감 33%
- 4주가 지난 환자에게서는 pain fear avoidance belief와 연관되어 있음.
Thus, fear-avoidance beliefs such as pain expectancies begin in acute pain and precede other psychosocial
problems that develop as acute pain becomes chronic. Linton and colleagues found that fear-avoidance beliefs were even prospectively related to the development of acute pain and dysfunction in asymptomatic individuals (75). Those with scores above the median had twice the risk for acute LBP (odds ratio 2.4).
Catastrophizing was also evaluated, but its predictive power was more limited (odds ratio 1.5). Although numerous studies demonstrate the effectiveness of cognitive-behavioral strategies (30,36,65,74,80,95) simpler re-activation approaches may be all that is needed. Mannion reported that three different active care approaches, none of which consisted of psychological or cognitive-behavioral approaches, all improved psychological variables related to self report
of pain and disability (87).
Abnormal illness behavior contributes to a slower or inadequate recovery (92,97). Patients who equate hurt with harm develop a disabling form of thinking. They develop fear-avoidance behavior that promotes deconditioning (Fig. 1.9) (8 1 ,116). It is important to identify the patient who is fearful and avoid encouraging them to take on a "sick role." According to Troup (113), "If fear of pain persists, unless it is specifically recognized and treated, it leads inexorably to painavoidance
and thence to disuse."
Risk Factors for Prolonged Cervical and Upper Quarter Pain
The Sensitivity and Specificity of Cervical and Upper Quarter Pain Predictors
Grading System for Evaluating Prospective Psychological Risk Factors of Neck and Low Back Pain Chronicity
Yellow Flags Risk Factors for Acute LBP Becoming Chronic
History and Symptoms
• Duration of symptoms 4-12 weeks (112)
• Sciatica (8,13,33,70,90,103,112)
• History of previous episodes of back pain requiring treatment (8,13)
• Severe pain intensity at 3 weeks (8); at 4 weeks (26); at 6 weeks (41); and at 8 weeks (28)
• Delaying treatment at least 7 days (90,115)
• Widespread pain (112)
Examination
• Positive straight leg raise test (8,19,66,71)
• Positive neurological examination (motor, sensory, reflex) (47,66,52)
• Positive range of motion (ROM) or orthopedic findings (47,52,68,109,112)
• Lack of centralization of peripheral symptoms with repetitive ROM testing (123)
Psychosocial
• 3 or more Waddell signs of illness behavior (70,90,122); no (33)
• Self-rated health as poor (10,112) [(26) at 4 weeks]
• Symptom satisfaction (13)
• Fear-avoidance beliefs (3 questions) [(26) at 4 weeks] (34,49,66,77-79)
o belief that physical activity makes pain worse
o belief that if person has pain with activity they should cease the activity
o belief that person with pain should not perform normal activities with pain
• Anxiety (14,79,80,94)
• Coping (praying, hoping, catastrophizing) (8,70) [large effect sizes (94)]
• Distress/depression (22,27,77,108) [odds ratio approximately 3 and medium magnitude effect size (94)]
• Poor locus of control (yes: 47,70,77-79) (no: 8,88)
• Low expectation of recovery (51,77-79)
• Blaming others (90)
• Negative family or workplace social situation (90)
• Increased number of children being cared for (47)
• Anticipation of future disability or ability to return to work (51,77,78)
Work-Related
• Receiving compensation (90)
• Litigation (90)
• Physically demanding job (or perception of) (47,51,33)
• Job dissatisfaction (3,12,13,19,112,125) (no: 77-79)
• Subjective work-related ability (47)
• Prior disability in the prior 12 months (77-79)
• A workplace unable to provide light duties on return to work (33)
• Low job control or low supervisor support (60)
Functional
• Light work tolerance (77-79)
• Sleep (77-79,90)
• At least moderate physical disability (score of 201100 or higher with the Oswestry) (33)
Evaluation
There are five signs that are evaluated. The presence of three out of five of these signs is significantly correlated with disability (l18). The signs are:
1) Superficial or nonanatomic tenderness-widespread sensitivity to light touch in the lumbar region and pain referred to other areas such as thoracic, sacrum, or pelvis.
2) Simulation-axial loading (light pressure to the skull should not significantly increase low back pain. Passive rotation of the shoulders and pelvis together in a standing patient should not reproduce low back pain.
3) Distractions-difference of 40 to 45 degrees between the supine and seated straight leg raising tests.
4) Regional disturbances-sensory or motor disturbance ("giving way") that is not neurologically correlated.
5) Overreaction-inappropriate overreaction such as guarding, limping, rubbing the affected area, bracing oneself, grimacing, or sighing are all signs of illness behavior.
Because three of the five signs include two separate tests, there are a total of eight tests that make up the five Waddell signs. For those signs that include two tests, if either of the two tests is positive, a positive sign is reported. In other words, it is not necessary for both tests to be positive to result in a positive sign, but rather only one of the two tests. The final score is documented as the total num ber of positive signs over five (e.g., 2/5). Non-organic LBP must be considered and the psychosocial issues clinically addressed when three or more of the five signs are positive. Wernecke
et al. found that these behavioral signs could be improved by a physical rehabilitation program ( 1 22).
Waddell's signs were shown to be an integral component of a broader assessment of risk for non-return to work in chronic LBP individuals (67). The full assessment also included measurement of pain intensity, a step test, and a pseudo-strength test. If two of the four tests were positive, correct prediction of risk occurred with a positive predictive value of 0.97 and sensitivity of 0.45. Pain intensity was positive if the Numeric Rating Scale (0-10) score was 9 or 10. The step test was performed for 3 minutes and was positive if the patient stopped it prematurely (see Chapter 1 2). The pseudo-strength test involved the patient holding two 3-kg weight with straight arms against gravity for 2 minutes. The test was positive if the test was stopped prematurely. According to Waddell this examination should not be performed on acute patients (118).
1) Tenderness
a) Superficial: Superficial tenderness is defined as widespread sensitivity to light touch of the skin over the lumbar spine. This is evaluated by applying light touch over the lumbar skin in a manner that should NOT normally provoke pain (Fig. 9.2).
b) Non-anatomic: Non-anatomic is defined as bone tenderness over a wide area, often extending to the thoracic spine, sacrum, or pelvis. This is characterized by a non-anatomical, wide area of pain, not localized to one structure or anatomical region.
2) Simulation
a) Axial compression: apply light downward pressure on the head in the direction of the floor (Fig. 9.3). A modification of applying the pressure to the shoulders is suggested to avoid cervical spine symptoms.
b) Trunk rotation: do not turn the shoulders more than the pelvis when trunk rotation is applied (Fig. 9.4).
3) Distraction: Sitting Versus Supine Straight Leg Raise (SLR)
• Sitting distracted SLR (simultaneous testing of the plantar reflex) and supine undistracted SLR (Figs. 9.5A and B)
• More lhan a 40-degree difference was defined as significant
This is somelimes referred lo as a positive "flip" sign as lhe palient is "flipped" from supine to sitting (or vise versa).
4) Regional Disturbance
a) Motor (Fig. 9.6A)
b) Sensory (Fig. 9.6B)
• Positive test: non-analomical neurological loss and/or inconsislency on repeated testing
• Findings may include (bul are nol limiled to): breakaway weakness, multiple weakness in an extremity (rule out pain-induced vs fear-induced weakness), global or patchy altered sensory findings
5) Exaggeration/overreaction
This sign includes an inappropriate response at any time during the entire physical examination when exaggeration, overreaction, or a disproportionate response such as a tremor, outcry, or collapse occurs (Fig. 9.7). A list of descriplors includes the following:
• Assisted movemenl (cane, walker, furniture)
• Rigid or slow movement
• Bracing: both limbs supporting weight while seated
• Rubbing the affected area for more than 3 seconds
• Clutching, grasping affected area for more lhan 3 seconds
• Grimacing
• Sighing with shoulders rising and falling
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