Approach to the Diagnosis of Pain
Clinical Strategies
Copyright 2008
James Armstrong PA
Ashley Davidoff MD
Diagnosis
Diagnosis is a determination of the nature of a disease. An orderly and progressive algorithm must be followed to arrive at the most accurate diagnosis and subsequently institute the most effective treatment. Meticulous attention to the nature of the pain and its associated symptoms in the clinical history, a focused examination complimented by relevant laboratory investigation and appropriate diagnostic imaging is necessary. Of these, the most important is the clinical history.
Clinical Facets of Pain – History
As we have seen from the previous modules, pain is complex and often individualized. Acute pain tends to be more common, and easier to deal with than chronic pain. In the acute situation when pain is purely somatic, it commonly follows relatively simple rules. It is well defined, well localized, and there is often a precipitating event. Visceral pain starts to add complexity as the pain is more vague, may manifest as discomfort, is poorly localized, and is often associated with other symptoms. As pain becomes chronic, whether somatic or visceral, neuropathic or psychological, diagnosis may be srarightforward but treatment becomes more difficult.
Age of the Patient
Although we are really dealing with adults in this module, it is reasonable to frame pain in the context of age. It then becomes relevant to consider how perception of pain differs with age. For example, pain is a sensation that can be appreciated by mid to late gestation inferring that preterm infants can perceive pain. The newborn responds to pain with crying, body movements or facial expression. By one month, babies can be comforted when in pain as they start to recognize human interaction and comfort provided by a loving caregiver. Preschoolers can start to describe location and severity of pain and respond with crying and anger. Their memory of “shots” and avoidance in the future of such an experience is vivid. Children have two general responses to pain. They either develop an ability to “be brave” in the face of pain, or they may be overcome with fear. In adolescence, the two groups with black or white responses in their acknowledgement persist. As mortality and fear of disease becomes more realistic in adulthood, pain is either ignored or rapidly dealt with by a visit to the caregiver for the assurance that it does not represent a mortal illness. With aging, acceptance of pain as part of life becomes the common response.
Pain Descriptors
Pain descriptors are verbal terms used to characterize pain. Although they are subjective expressions of pain, descriptors can be organized into helpful tools when assessing a patient. The purpose of using pain descriptors is two fold: First, they provide structure to an otherwise subjective interview. Patient and clinician can systematically navigate through an organized array of terms to create a narrative that may define the pain source. For example, the pain of aortic dissection is often described as a “tearing” sensation felt in the center of the chest and the very moment of onset is easily recounted.
The second effect of descriptors is that they prompt the patient to discuss more pain features than he/she might not have otherwise. This approach also invites the patient to express the pain without the clinician scripting the narrative. For example, a middle aged male patient complaining of chest pain would raise serious concerns as an isolated descriptor for ischemic heart disease. However, when asked about aggravating factors, the patient links the pain to deep breathing and then remembers a blow to the chest from a softball the day before. The descriptor of aggravating factors prompted the patient to more accurately describe the pain and subsequently directed the clinician toward a probable non-life threatening source.
As with pain scales, there are many versions of descriptor tools tailored to age groups and medical specialties. These instruments are all designed to assess baseline and therapeutic pain descriptions. Although physical diagnosis texts vary, the most common descriptors include preciptating factors, duration, onset, character, situation, severity, aggravating and relieving influences, radiation and associated symptoms. The acronym is PDOCSSARRA. Other descriptors like pattern, location and level of impairment may be added to bring more depth to the patient’s story, keeping in mind the time constraints of the healthcare setting.
Precipitating factors
“What were you doing when the pain started?” This is a good question to initiate the discussion because it represents the beginning of the patients story.
Precipitating factors describes the situations or circumstances that triggered the pain.
Examples where this question has relevance include excercise related pain which is typical of ischemic pain. In the case of angina, it is chest pain while walking that is typically relieved by rest. Abdominal angina is pain with eating, and claudication is usually discomfort in the lower extremity induced by walking. Right upper quadrant pain precipitated by a fatty meal brings to mind acute cholecystitis, while right upper quadrant pain following an alcoholic binge may constitute acute fatty change of the liver. Acute back pain after “just picking up my young son” brings to mind a herniated disc.
Pain that awakens somebody from sleep usually is given serious consideration because it comes with no supratentorial element and is generated purely by something physical. It can herald a catastrophic event such as a rupture of a structure. Ruptured berry aneurysm, aortic dissection, acute myocardial infarction, ruptured ectopic pregnancy are considerations depending on the site of pain. Peptic disease is also classically described as pain that awakens a patient 2-3 hours into their sleep.
Sometimes the precipitating event concurs with a physiological event and this is viewed as a precipitating factor. Examples include menstrual cramps and mittelschmerz – which is midcycle pain corresponding to ovulation. Excessive excercise is also a physiological event that may precipitate pain.
The onset of the spring or fall with dusts and pollens sometimes induces sinus headaches.
The precipitating factor as discussed above is often a major criterion on which the diagnosis rests. It is of course an essential question stated to open the dialogue and initiate the story of the pain.
Duration
Time and pain can be framed into two important contexts. The first is historical: “How long have you had the pain for?”. The second is: “How long does the pain last?”
There is a significant difference and clinical bias depending on whether the pain has come and gone for years, as opposed to pain that has just started. A patient who presents with chest pain that has come and gone for years is treated differently from the patient who has acute pain that started a few hours earlier. The latter history raises more serious concerns, and life threatening disease must be excluded, while the former may represent a serious condition like coronary artery disease, but the danger is not necessarily imminent.
Hyperacute Shearing Chest Pain |
| Hyperacute shearing and lancinating chest pain characteristic of an acute dissection, is viewed differently from the angina like pain that has occurred over years.
71197c10c chest pain character shearing sharp lancinating acute aortic syndrome aortic dissection penetrating ulcer acute aortic hematoma ruptured aorta ruptured dissection CTscan davidoff Art Courtesy Ashley Davidoff MD 49640c06 |
The second question of “How long does it last?” also has significant relevance and we will use the chest pain example once again. Chest pain that lasts a few seconds and is fleeting is not angina and usually is not of clinical concern. Angina and ischemic pain in general are caused by the chemical build up of lactates which take time to accumulate and also time to disappear. Angina usually lasts from 1-15 minutes and may even go as long as 30 minutes. However once chest pain goes beyond 20 minutes it becomes concerning and unstable angina is considered.
The relationship between time and pain is an important and essential characteristic for the clinician to elucidate and time periods will range from fleeting (measured in terms of seconds), to years. It is sometimes not easy for the patient to describe or remember when the pain started or how long it lasted, and often the patient is required to correlate the pain event in light of other events in their life. We have developed a few charts that may help the patient describe and recall when the pain started.
Seconds Minutes and Hours |
| The chart describes acute pain in graphic terms. The top line shows the red hand representing seconds ranging consecutively from a few seconds (less than five) in the first image (top left) to 30, (middle top) and then to about a minute (right top). The second row with the long teal hand , represents the pain duration in minutes. The first left image is pain in the 5 minute range the second in the 30 minute or less range while the third represents pain going on an hour. The last row with short green hand being relevant represents pain that lasts an hour or two, (bottom left) the second represents pain in the 5- 6 hour range (bottom middle) and the last in the close to 12 hour range(bottom right).
77118c.81 time clock duration seconds minutes hours Davidoff art Courtesy Ashley Davidoff MD |
Days and Weeks |
| The second chart is in the form of a weekly calender and shows pain in terms of days. It is a graphic reminder for the patient who tries to remember which day the pain started and allows the patient to integrate the symptom with another event of the week eg “Oh yes it started on Sunday when I was in church.”
77119b01 time duration age Monday Tuesday Wednesday Thursday Friday Saturday Sunday Davidoff Art Copyright 2008 Courtesy Ashley Davidoff MD |
Months and Seasons |
| The third chart is in the form of a annual calender and shows pain in terms of months and seasons. It is a graphic reminder for the patient who tries to remember which month the pain started and allows the patient to integrate the symptom with another event of the year eg “Oh yes it started in the summer when were at Granma’s BBQ.” Each season is represented by a different color.
white = cold and winter of January lightest pink = late winter early spring light pink = early spring dark pink = early summer green = early summer blue = summer proper pale yellow = mid summer bright yellow = late summer orange = early fall brown = late fall dark gray = early winter light gray = winter
and back to January white = mid winter
77119b04 time months seasons age one year colors white = cold light pink = early spring pink = early summer green = early summer blue = summer pale yellow = mid summer bright yellow = late summer orange = early fall brown = late fall dark gray = early winter light gray = winter white = mid winter very light pink = late winter Davidoff Art Courtesy Ashley Davidoff MD |
The distinction between and the implications of acute and chronic pain are therefore important and are defined by the above question; “For how long have you had the pain?” When pain lingers beyond a realistic healing time, the experience becomes chronic. Despite resolution of the injury, there is lingering activation of pain fibers perceived by the patient. Additionally, there are often disabling features beyond the sensory manifestations of chronic pain which can make treatment difficult. These include motor dysfunction, muscle tension, depression, personality changes, anorexia, and sleep disorders for example, all of which can be severely life altering to the patient.
Onset
“Did it start suddenly or slowly?” or “Did it build up quickly to peak or slowly to peak?” are the type of questions that define onset. In general pain that starts suddenly, is somatic in origin while pain that is gradual in origin is usually visceral.
” I was sitting having dinner with my family and suddenly developed a the most severe headache of my life ” raises the question of a ruptured berry aneurysm.
“I woke up in the morning with a mild headache and it got worse during the day and is at its worst now, but I have had similar more severe headaches in the past” This does not sound like a berry aneurysm
Thus “onset” describes the arrival of pain.
Character
“What did it feel like? We are now getting to the exciting part of the story. Was it sharp, cutting, pinching shooting, stabbing, knife like or dull and bruise like? Was it throbbing, gripping aching, tearing, lancinating or like lightning. Did it feel like pressure, heaviness, dull or nauseating or more like real piercing pain? What is colicky, spasmodic or squeezing like bad gas cramps?” Was it tingling or numbing?
Each of these characteristics do not always imply a specific disease. In general, sharp pains tends to be somatic while dull aches tend to be visceral. Colicky pains tend to originate from structures that peristalse such as the bowel, biliary ducts and ureters. Lancinating pain in the chest or back suggests aortic dissection. Pain that is dull and deep in joints or limbs usually implies musculoskeletal origin. Pain that has numbness or tingling has an element may imply a neuropathy. Pain in the chest that has a pressure like character raises concern for cardiogenic pain.
Situation
” Where exactly does it hurt? Can you point with a finger or is it easier to use your hold hand to define the position of the pain?” “Does it fel deep or does it feel like it is coming from the muscles or skin?”
Also called location, situation defines the affected area of the body and the depth of pain as either superficial or deep. The situation can vary from well localized pain to that which is perceived to originate from a general area that is not well defined.
Somatic pain tends to be well localized in which case the patient points with a finger, while visceral pain tends to be more diffuse and the patient uses the whole hand to decribe the location of the pain.
Severity
“How severe is the pain?” “Is it the worst pain of your life or is only mild?” On a scale of 1-10 with 1 being mild and 10 being the worst ,where does it fit into the scale?”
With the question of severity we start to get into individual perception of pain. What may be severe pain for one person may be mild for another. There have been several classifications used to evaluate the severity of pain
grading based on the 1-10 Wong Baker scale
grading based on mild moderate severe scale
grading based on the facial illustration
grading based on color
grading based on the the degree to which the patient is disabled by the pain.
Pain Scales
There is no definitive pain scale across all medical fields. Instead, there are a multitude of scales specific to different medical areas. A cancer pain scale for instance may focus on degrees of bone pain and therefore differ from that used for rheumatoid arthritis. To that end, the National Institutes of Health Pain Consortium recognizes six different scales to measure pain intensity and efficacy of treatment. (NIH Pain Consortium)
The most patient friendly pain measure is the Wong-Baker Faces Pain Rating Scale, also called the Universal Pain Assessment Tool. The patient scores the level of discomfort from 1-10 in increasing intensity by selecting a facial expression diagram that best matches the experienced pain. (see diagram below). Although there are many other examples, this is the most widely used pain scale given its simplicity across all patient populations.
Wong Baker Pain Scale
|
Wong Baker Pan Scale
|
| The top row shows a numerical value for the pain with 1 being mild and 10 being the most severe. The next row uses a verbal descriptor. The next line is a facial grimace scale with specific colors representing degrees of pain, and the next line shows activity tolerance related to pain and translations in subsequent rows to a variety of languages. which has equivalemts in other languages lower. |
| (Wikipedia need permission to Publish) 53892.8s |
The WongBaker Scale is an excellent practical and comprehensive diagrammatic that describes the scale of severity well and is universally accepted. A simpler modified diagram is shown below that may be easier for some to use.
Modification of the Wong Baker Scale |
| A modification of the Wong Baker scale is illustated above. It offers the advantage of being slightly simpler, but does not offer the facial grimace scale useful for children, nor the interpretation into other languages.
77114c.89 Davidoff pain scale modification Wong Baker no pain minimal mild moderate moderately severe severe ignored interferes with tasks interferes with concentration interferes with basic needs needs bed rest white green blue maroon orange red Davidoff art Courtesy Ashley Davidoff MD |
Aggravating Factors
“What makes the pain worse?”
Aggravating factors is self explanatory and describes activities or environments that intensify the pain. Plantar fasciitis pain is usually worse after prolonged rest thus hobbling its victims when they first ambulate in the morning. Deep inspiration aggravates pleuritic pain and movement in general aggravates traumatic musculoskeletal pain.
Relieving Factors
“What makes the pain better?” “Does anything help the pain?” “What medicine have you taken, and has it been effective?”
Relieving factors describes activities or environments that treat or attenuate the pain. Examples include angina that resolves with cessation of exertion or tendonitis pain that lessens ironically with use and worsens with rest. Sitting forward may relieve the pain of pericarditis. Antiinflammatory agents relieve pain that has inflammatory causes, while niotroglycerine relieves angina and esophageal spasm.
Radiation
“Does the pain radiate anywhere else in the body?”
Radiation identifies a part of the body to which the pain migrates. Sciatic pain from lumbar spinal nerve irritation will often radiate down the posterior aspect of the affected lower extremity. Angina may start in the precordium and radiate to the neck and down the left arm. Appendicitis may start as a periumbilical pain, at which time it is visceral and by implication is referred pain, and then migrate to the right lower quadrant at which time it is somatic and has spread to the peritoneum.
Associated Symptoms
“What other symptoms do you have with the pain?” “Are you nauseous?” Did you vomit? Did you sweat? “Did you faint?” Did you have diarrhea?” “Did somebody comment that you were pale?” Were you short of breath?
We have noted in the basic sciences of pain in part 1, that the autonomic and limbic systems are activated as the pain signal travels through the brain. In general the sympathetic system is turned on accounting for anxiety, tachycardia, pallor sweating, and sometimes associated with a sense of impending doom. In some patients particulalrly when the pain is severe vagal influences intrude and patient may be nauseous may vomit, and may even faint.
A patient who presents with pain reminiscent of a myocardial infarction and has associated shortness of breath suggests pump failure and a large infarction.
Clinical Examination- by Anatomical Regions
A brief outline of common clinical signs in the evaluation of pain follows.
Head and Neck
Pain syndromes of the head and neck vary according to the degree and area of injury but are generally poorly tolerated due to the anatomical confines of these regions. The head and neck anatomy is highly vascularized and well innervated with both somatic and cranial nerve fibers. Pain symptoms therefore are often accompanied by neurological findings. Causes of head and neck pain include trauma, neoplasm, infection and treatment related syndromes after surgery or radiation therapy.
The clinical examination for pain in the head and neck region requires meticulous examination of the cranial nerves, evaluation for neck stiffness, extension, flexion and rotation range, evaluation of the temporal arteries, pressure palpation of the sinuses, and evaluation of the lymph nodes in the neck and occipital regions.
Chest
Due to the prevalence of cardiovascular disease and its common manifestation of thoracic symptoms, chest pain receives priority status when described by the presenting patient. Chest discomfort can also occur in the absence of objective findings however usually at the expense of healthcare resources to exclude the more serious etiologies as described in the chest pain module. Examination of the chest is not very helpful except imn a few circumstances. When costochondritis is suspected then pressing on the rib cage may induce pain. When pericarditis or pleurisy is considered, then a rub may be heard. New murmurs of valvular incompetence or a new 4th heart sound all implicate the heart as a cause of chest pain. Pleural effusion as depicted by dullness to percussion or pneumonia as depicted by whispering pectoriloquy are useful signs on the clinical examination for these disease entities
Abdomen
Excluding direct trauma, abdominal pain is often visceral in nature and therefore difficult to delineate. Visceral pain receptors are stimulated by distension, contraction, inflammation and ischemia. An understanding of these characteristics and a sound knowledge of abdominal anatomy can be helpful in demystifying abdominal pain. Exquisite superficial pain induced by minimal focal palpation is reminiscent of peritonism and suggests peritonitis. Murphy’s sign with pressure exerted over the gallbladder region that induces pain on inspiration as the gallbladder comes down and forward is characteristic of acute cholecystitis. Focal tenderness in the region of McBurney’s point, 1/3 the distance between the anterior superior iliac spine and the umbilicus raises the possibility of appendicitis. Flank bruises in a patient with severe abdominal pain following an alcoholic binge is characteristic of Grey- Turner’s sign of acute pancreatitis.
Pelvic
The pelvis is another highly vascularized area comprised mostly of the reproductive organs and a multitude of lumbar and sacral nerve plexi. Due to its anatomical proximity to the abdominal viscera, pelvic pain may often reflect an abdominal process.
Pelvic inflammatory disease is characterized by cervical tenderness and a discharge, while mid-cycle pain may reveal a large cystic mass in the adnexa.
Back
Back pain is significant in its societal frequency and impact on the workforce. There is a ninety percent lifetime incidence of back pain in the adult population and it ranks second only to the common cold for worker absenteeism. Although classically back pain is a self-limited manifestation of muscle spasm in response to injury, disorders of the spinal structures and subsequent nerve roots can cause chronic, life altering pain and disability. Evaluation for muscle spasm, sensory and motor deficits and rectal tone are important clinical features in the work up of patients with back pain.
Extremity
The most common cause of extremity pain is injury to soft tissue, bone or cartilage that is either acute or repetitive. Pain radiation is common in the extremities due to alignment of sensory and motor nerves within the fascia. For example, repetitive stress injury to the forearm causing tendonitis in tennis players is often manifested as elbow pain thus invoking the nickname “tennis elbow”. Degenerative joint disease in the elderly is a frequent source of chronic pain and disability often with surgery as the only remedy.
Examining the range of motion of joints, as well as the motor and sensory functions all need to be examined in patients presenting with limb pain.Neurological deficits in any part of the body associated with pain is a serious finding, and probably the most important contribution of the clinical examination. Imaging techniques can find many abnormalities that are missed on clinical exam, but they cannot equal in any way the sensitivity of a neurological examination.
Laboratory Investigation
The laboratory investigation has its most important contribution in determining whether the disease is inflammatory or infectious. To this end, the blood count and specifically the white cell count are important. Erythrocyte sedimentation rate and c reactive protein also help in defining activity and are elevated in both inflammatory and infectious diseases. When a patient complains of pain and if any of the aforementioned studies are positive, we know we have to take the patient seriously and a diagnosis should be pursued. Urinary examination is important in patients with renal colic or pyelonephritis. Chemical and cytological examination of pleural fluid, or CSF in the appropriate clinical setting can be useful in diseases such as pleurisy, and meningitis. The EKG is extremely important in the work up of the patient with chest pain, which if abnormal creates a cascade of events in the workup aimed at excluding a myocardial infarction
Imaging Pain by Anatomical Locations
The advancement of technology over the last 15 years has enabled the medical world to evaluate morphological detail of the body to an exquisite degree. This has been a tremendous advantage and has avoided unnecessary surgery in some cases and directed appropriate surgery and treatment in other cases. To some extent, the evolution of imaging has also been to our disdvantage as a community as the images we see often have no relevance to the patient’s symptomatology. On the other hand, the reputation of imaging as an accurate diagnostic tool has created a reliance on imaging but also has resulted in abuse of the technology.
Head and Neck
One of the first studies performed in the patient with a new headache which is clinically concerning is a CTscan of the head. CT is able to make the distinction between a life threatening rupture of a ruptured berry aneurysm and a non hemorrhagic condition. An example is shown below.
When a patient presents with a headache, sinus congestion focal pain over the sinuses and a fever the diagnosis of acute sinusitis is clinically apparent and no further workup is necessary. Sometimes the clinical presentation is less revealing and CT is highly sensitive to the diagnosis and is also able to reveal the extent of the disease.
Pansinusitis |
| The CTscan is from a 28 year old male who presented with headaches. The CTscan shows easily identified pansinusitis. Image b, (reflects an overlay of image a) and shows light yellow total opacification of the frontal sinuses, light orange opacification of the ethmoid sinuses, and dark orange opacification of the sphenoid sinuses. Image d is an overlay of image shows almost total opacification of the maxillary sinuses (darkest orange) aas well as the ethmoids (light orange)
75899c02 28 male presents with headache and fever fx pansinusitis with complete opacification of all the sinuses yellow = frontal sinus orange = ethmoid sinuses red = sphenoid sinuses maroon = maxillary sinuses dx acute pansinusitis CTscan Courtesy Ashley Davidoff MD |
Chest
Chest pain is a common and concerning symptom. In the young thin tall male who presents with acute sharp chest pain and shortness of breath requires an urgent chest X-ray to exclude spontaneous pneumothorax caused buy rupture of an apical bulla.
|
| This is the type of CXR that sends shivers down the spine. The overall blackness of the left chest cavity, in association with a nubbin of lung tissue in the ipsilateral hilum and rightward mediastinal shift is characteristic of a tension pneumothorax with total atelectasis of the left lung. Immediate and urgent decompression with a chest drain is indicated. One must also remeber that if a tall thin young patient presents with chest pain the diagnosis of dissecting aneurysm in a patient with Marfans syndrome has to be considered.
Courtesy Ashley Davidoff MD 42525 code lung pleura dx tension pneumothorax plain film CXR 5star medical students |
Tall ThinYoung – Spontaneous Pneumothorax with Mediastinal ShiftIn the older patient who presents with chest pain, the algorithm is directed toward excluding life threatening myocardial infarction. As EKG and enzymes start to look like infarction, the question of cardiac catheterization to exclude the presence of acute thrombus evolves.
|
Abdomen
The abdomen has the largest variety of organs of all the cavities and each organ and system has classical manifestations. In general, ultrasound is the technique of choice in the pediatric population, young adults and pregnant patients. It can also be a sensitive test in the evaluation of right upper quadrant pain. CT is used for pain in the left lower quadrant to exclude diverticulitis and in the right lower quadrant in the non pediatric population where appendicitis is most common. CT is also effective for the patients where pain is vague and a global view of the abdominal contents is needed. The biliary ducts are best evaluated initially with ultrasound and then by ERCP or MRCP. MRI otherwise does not have a large role in the assessment of pain in the abdomen.
Pelvic
CT, MRI, and Ultrasound all have a role to play in the pelvis. Ultrasound is the study of choice in the evaluation of the uterus and adnexa as a first line, and if this fails, then MRI is used. CT is most useful for gastrointestinal disorders including colitis and diverticulitis.
Back
Back pain is a common disorder and is most commonly caused by disc disease. It is imprudent to order imaging examinations on all patients with back pain. Generally, plain films are insensitive to the important soft tissue changes that have relevance to the pain. Extensive degenerative changes as identified on plain film may not be associated with any symptoms, while a minimal disc bulge may only be apparrent on MRI. Obtaining a normal plain film examination may cause significant symptoms. MRI should be reserved for those patients with associated symptoms and signs of sensory or motor compromise caused by pressure effects of the soft tissues on the nerve or in those patients in whom more serious disorders such as metastases are a consideration.
Extremity
Sports injuries and chronic degenerative changes are the most common causes of extremity and joint pain. For the sports injuries, both plain films and MRI are utilized. Although plain films are sensitive to fractures, MRI is exceedingly sensitive to soft tissue injury and the associated presence of edema and hemorrhage. For the arthritides, plain films are excellent and often adequate.
Conclusion
In the clinical realm of pain, the medical history is probably the most important part of the diagnostic workup. It is thus imperative for the clinician to actively and meticulously question and listen to the patient during the history taking and examination. The subsequent use of laboratory examinations help direct the work up and identify those pains that may be inflammatory or infectious in origin. Modern imaging techniques have advanced the accuracy of diagnosis significantly, but they are expensive and should be used prudently.
|
Thrombus in LAD then Thrombolysed
