WHY CHRONIC PAIN PATIENTS ARE

MISDIAGNOSED: and how to make a proper diagnosis

Course 12www.MarylandClinicalDiagnostics.com

Nelson Hendler, MD, MSFormer Assistant Professor of NeurosurgeryJohns Hopkins University School of MedicinePast president –American Academy of Pain Management

Missed Diagnoses-Neck and Back Pain • Hendler et al Overlooked Physical Diagnoses in Chronic Pain

Patients Involved in Litigation, Psychosomatics, ’93• N= 60• 67% were misdiagnosed “lumbar strain, cervical strain, chronic

pain syndrome, conversion reaction.”• Hendler, et al, Overlooked Physical Diagnoses in Chronic Pain

Patients Involved in Litigation: Part II Psychosomatics,‘96• N= 120• 40% were misdiagnosed “lumbar strain, cervical strain, chronic

pain syndrome, conversion reaction”• These 180 patients, from two studies, really had facet syndrome,

disrupted discs (internal disc disruption), thoracic outlet syndrome, nerve entrapments, and radiculopathy, confirmed by objective physiological testing.

Why Patients are Misdiagnosed• Doctors don’t spend enough time with a patient taking a

careful history.• Doctors rely on anatomical tests, such as MRI, CT, and

X-ray to make diagnosis• Pain is a physiological condition.• Physiology is measuring a response to a stimulus.• Anatomy is taking a picture, but you can’t take picture

of “pain.”• If you want to know “Is the oven hot?” would you use a

photo or a thermometer to determine this? • Doctors need to use physiological tests, such as

provocative discogram, facet blocks, root blocks, nerve blocks, bone scan, neurometer studies for sensory nerves, Indium 111 scans, PET scan, etc.

Cause of Misdiagnoses (cont)• Failure to recognize that a single clinical

manifestation may have multiple etiologies (a flat tire).

• Failure to realize a single pathological condition may have multiple clinical manifestations (Lyme disease)

• Failure to take a careful history. • Failure to understand the specificity and

sensitivity of tests. • Relying on anatomical tests to make a diagnosis

rather than clinical judgment or physiological tests.

• Not believing a patient.

Example of Flaws of Anatomical Tests• ANATOMICAL TESTING BENEFIT:• I have a pain in my thumb.• Take a picture and find a vise on my thumb.• Perform “visectomy” and the pain goes away.• BUT - ANATOMICAL TESTING FAILURE: • I have a pain in my thumb.• I have hit my thumb many times with a hammer• Take a picture, but no hammer is seen• What caused the pain? You have to ask why.• This demonstrates the need for a careful history

“Misdiagnosed” Definition• Many patients are misdiagnosed. What is that? • Misdiagnosis: The referring physician has not

mentioned a certain diagnosis (overlooked).• The referring physician has used a descriptive

“diagnosis” such as “low back pain.” • The referring physician has offered a wrong diagnosis

without any objective data to support it, i.e. RSD, lumbar strain, fibromyalgia, psychogenic pain, fibromyalgia, etc.

• The www.MarylandClinicalDiagnostics.com Diagnostic Paradigm establishes a diagnosis, previously unmentioned by referring physicians, which can be documented by objective or interactive (blocks, provocative discograms, etc.) testing.

What is Evidence Based Medicine?

It is using scientific evidence to prove a point. • Meta analysis is a review of medical literature.• Epidemiology reviews the incidence (number of new

cases a year) and prevalence (number of cases at any one time) of a disease. It is the basis of actuarial data.

• Outcome studies report the results of surgery or interventions. Selection criteria can influence results.

• Population definitions can alter results. There are clinics that will not see claimants with active litigation. Other clinics count “return to work” as being back on the job only one day. There are regional, genetic, and sociological differences, such as educational background, training, language fluency, age, etc. that influence reported results.

Flaws in Meta-Analysis Research

• Richard Payne, MD (Clin. J. of Pain, ’86) at Cornell-Memorial Sloan Kettering did a meta analysis of patients with surgical sympathectomies for the treatment of causalgia (CPRS II).

• He found the success rates reported in the literature ranged from 12% to 97%.

• Sources of flaws in this analysis: diagnostic criteria for causalgia, outcome criteria, surgical skill, litigation, etc.? Each article was different.

What is a “Chronic Pain Patient?”

• Chronic Pain Patient –each article is like blind men describing an elephant. Each reports only what was seen in their clinical setting, but never sees the entire population.

• The type of patient is rarely mentioned in the literature, i.e., litigant versus non-litigant.

• Selection criteria for a patient population is essential for determining proper intervention and meaningful outcomes.

Waddell Signs as part of a physical exam• Waddell signs are five physical tests, like hitting a

patient on the head to see if their low back hurts, etc. • Fishbain, et. al., (Pain Medicine, vol. 4, ’03) did a meta

analysis of 61 studies that reported using Waddell signs.• Positive Waddell signs do not correlate with

malingering, secondary gain, hysteria, psychological distress, abnormal illness behavior, nor somatic amplification

• They do not discriminate organic vs. non-organic problems, but they are misused that way.

• They do predict poor treatment outcome.• There may be a real organic basis for positive signs.

Types of Tests Used for Validating Pain and What They Measure

• Anatomical Tests: MRI, CT, 3D-CT, X-ray, discogram, myelogram – a picture.

• Physiological Tests: Flex-Ex. X-rays, bone scan, nerve blocks, root blocks, facet blocks, provocative discogram, gallium scan, Indium 111 scan, phentolamine test, EMG/NCV, neurometers, 2 poster brace, body jacket with thigh spika- a response.

Anatomical Versus Physiological

• Anatomical • Takes a picture of the

body.• EXAMPLE• Oven on wall.• Take a picture.• Look at picture.• Can you tell if the

oven is hot?

• Physiological• Measures body

response- interactive.• EXAMPLE• Oven on wall. • Put thermometer in

oven. • Look at thermometer.• It says 375 F. Is it hot?

Specificity versus Sensitivity

• Sensitive Test• Always detects presence

of a disease.• However, may also report

other diseases as the first disease.

• Very sensitive, but not so specific- gives false positive readings

• Tine test for TB.

• Specific Test• When positive, it detects

only the disease in question.

• May overlook mild or variant forms of the disease.

• Very specific, but not so sensitive- gives false negative results.

• Mantou test for TB.

Specificity versus Sensitivity• Sensitive Test• Let’s catch a tuna.• Use a small mesh net.• Will catch a lot of fish,

and never miss a tuna. • Definitely will catch a

tuna, but will also get mackerel, perch and spot, which will require further sorting.

• False positive results.• Sensitive but not specific

• Specific Test• Let’s catch a tuna.• Use a big mesh net.• Everything in net will be

tuna.• Will catch large tuna, but

small tuna, mackerel, perch, and spot will not be in net, so no further sorting needed. Will miss some small tuna we would have wanted to keep.

• False negative results. • Specific but not sensitive

Flaws with Cervical Radiographs• Peterson, et. al. (Spine # 28 (2) pp 129-33, ’03).• 180 patients, mean age 49, 44% male rated pain

on VAS 0-10 scale & Neck Disability Index• Neck pain divided into no injury, injury (40.6%)

and those with litigation (5.1%).• No correlation between levels of degeneration, or

severity, and self rated pain or disability ratings.• Patients with injury had more pain and disability,

than patients without injury.• Women reported more pain and disability.

Flaws with Static Cervical X-rays

• Most patients complain of worse pain when they lean forward or backwards.

• Static (upright) X-rays do not demonstrate movement between the vertebral bodies.

• Flexion-Extension X-rays show what happens to the vertebral bodies when there is motion forward and backwards.

• Like a partially broken twig- the defect is not evident until the twig is put under tension.

Flaws with Just Anatomical Tests• MRI- Jensen et. al. N. Eng J. Med, ’94, 98

patients with no back pain, but 27 had protruding disc (28% false positive rate).

• MRI with Modic (vertebral end plate changes)-21/23 patients had + provocative discograms. BUT- in 90 patients with positive provocative discograms, only 23% had Modic changes, and 77% no changes in MRI. (Braithwaite, et al, Eur. Spine J. ’98). Therefore a 77% false negative rate for MRI

Anatomy and Physiology of a Disc• A disc is like a jelly donut.• Pain fibers are found in the rear 1/3 of the annulus

(donut) (Bogduk and McGuirk, Pain Research and Clinical Management, Vol. 13, p.121,Elsevier, 2002)

• A herniated disc has the jelly (nucleus polposa) protrude from the donut (annulus).

• Pain fibers can be disrupted, without any anatomical distortion of the annulus, so the MRI, CT and Myelogram are normal. (Bogduk and McGuirk, Pain Research and Clinical Management, Vol. 13, p.119-122,Elsevier, 2002)

• Pain from internal disc disruption (IDD) feels like a herniated disc pushing on a nerve root with pain in a radicular distribution.(Bogduk and McGuirk, ibid).

Herniated Disc vs. Internal Disc Disruption (IDD) (Bogduk and McGuirk, Pain Research and Clinical Management, Vol. 13,

p.119-122,Elsevier, 2002)

• Herniated Disc Internal Disc Disruption

CORD

CORD

MRI- shows disc herniation and cord compression

MRI -no disc herniation nor cord compression

Provocative Discograms• A physiological test, not an anatomical test.• Saline is injected into the donut (annulus)

portion of the disc, where the pain fibers are. • This injection distends the pain fibers. • If this injection reproduces the pain in the

distribution the patient normally feels pain, this is a positive test.

• Local anesthetic injected into the damaged disc take away the pain the patient normally feels.

Disc Anatomy and Provocative Discogram:Saline injection reproduces the pain, confirming

disc damage due to IDD, not seen on MRI Normal Disc

Herniated Disc

Internally Disrupted Disc (IDD), with normal MRI

Pain Fibers

Provocative Discogram

Needle

SalineNucleus Pulposa

Annulus

Pain

FibersInternally Disrupted Disc (IDD), with normal MRI

Comparison Herniated Disc versus IDD

• Herniated Disc • Internal Disc Disruption

Pain Fibers Pain Fibers

Annulus

Nucleus polpulsa

Further Debate on MRI vs Discogram

• 53 pts. with pain had both MRI and provocative discograms. 79.5% and 74.4% of patients with concordant pain on provocative discograms had no endplate changes (Modic) on T1 and T2 MRI images (Sandhu, et al, J. Spinal Disord, 2000).

• In 54 pts without pain, 24% had a “high intensity zone on MRI. Provocative discogram were + 69% of pts with Modic changes, and + 10% of pts without MRI findings. (Carragee et al, Spine, 2000).

Further Debate on MRI vs Discogram(Simmons, et al, Spine ’91).

• 164 patients with back pain.

• MRI abnormalities and + provocative discograms were found in 90/164 pts (55%).

• MRI and provocative discograms differed in 74/164 (45%) of the patients.

• 108 discs on MRI classified as abnormal were asymptomatic (37%).

Errors in MRI interpretation for Symptomatic Discs

• False + rate - MRI is 24%-37% in pts without pain.

• False neg. rate - MRI in pts with + provocative discograms ranges from 77%-79%.

• False positive rate for provocative discogram is 10%, i.e. produced pain at an asymptomatic disc.

EMG/NCV: The wrong physiological test. Patient has pain (sensory) not weakness (motor)

• Cross section of nerve, normal

• Cross section of nerve, damaged by compression

EMG/nerve conduction measures gross electrical activity of a nerve. 90% of electrical activity is from motor fibers. It takes a lot of pressure for a long time to damage motor nerves. Small sensory fibers can be easily damaged in a short period of time, but since they have so little electrical activity, the damage doesn’t show up on EMG/nerve conduction studies. Current perception threshold test (Neurometer studies) can measure sensory fiber activity

Motor fibers Sensory fibers compressionDamaged sensory fibers

3D-CT versus Regular CT(Zinreich, Long & Davis: J. Comput Assist. Tomography 1990)

• Study of 100 patients, without previous surgeries, with negative direct axial CT or 2-D multiplanar CT reconstructions.

• 3D-CT reconstructions found occult boney pathology 56% of time missed by CT.

• Study of 100 patients, with previous fusion, with negative direct axial CT or 2-D multiplanar CT reconstructions.

• 3D-CT reconstructions found occult boney pathology 76% of time missed by CT.

Sprains and Strains• Sprains are defined as stretching ligaments which hold joints

together (Bonica and Teitz -The Management of Pain p 375, 1990).

• Strains are defined as over-extension of a muscle, which move bone, with separation of muscle fibers (ibid, p.376).

• Sprain cause an average of 7.5 days restricted activity, 2 days of bed disability, and 2.5 days work loss (DHHS # PHS 87-1592, 1987).

• Spasm is an epi-phenomena, due to protective mechanism of gamma motor reflex loop, a spinal cord reflex. This means the spasm is not really the problem, but a result of the problem. What are the underlining problems that cause spasm ?

• You cannot have a sprain or strain that lasts 2 years! It must be something else! What could it be?

When a Sprain or Strain Lasts More than 6 weeks-What is it?

• If a ligament pull off a bone, there is excessive motion around a joint.

• This caused muscle spasm, because the muscles now have to do the work of ligaments to hold the bones together.

• When a disc is damaged, and there is a loss of disc space height, then there is less tension on the ligaments that hold vertebrae together, and there is excessive motion at that vertebral segment.

Mechanics of a Vertebral Segment

Normal Size

Neural Foramin

Normal Disc Height

Normal Vertebral Body

Alignment

Ligament holding vertebral bodies together

Vertebral slippage due to reduced disc space height and lax ligament

Mechanics of a Vertebral Segment

Normal Segment Damaged Segment

Flat disc results innarrowing of space and loose ligaments. Vertebral bodies move.

Taut ligaments hold vertebral bodies together

Direction of

force

Shock absorbing disc holds vertebral bodies apart

Two contravening forces. Vertebral bodies do not move.

Body

Moves

Facet Syndrome (Empting, Hendler, Kolodny, & Kraus, Tips on hard to manage pain

syndromes, Patient Care, pp.26-46,April 30, 1990)

• Pain in neck and shoulders and upper arm, or low back, and back of thigh.

• Worse with extension, better with flexion.• Temporary relief by facet blocks, at the level

above, at the level, and level below, since the facet is innervated by three levels.

• Facet denervation has 40% chance of 2 years of relief (North, R, Sequelae of facet denervations Pain, ’01)

Facet Blocks and Denervation(Empting, Hendler, Kolodny, & Kraus, Tips on hard to manage pain

syndromes, Patient Care, pp.26-46,April 30, 1990)

Normal Size

Neural Foramin

Normal Disc Height

Normal Vertebral Body

Alignment

Ligament holding vertebral bodies together

Vertebral slippage due to reduced disc space height and lax ligament

Facet Block

Missed Diagnoses of CRPS I (RSD) • Of 38 patients referred to a private clinic with the

diagnose of RSD (CRPS I) (Differential Diagnosis of CRPS I, Pan Arab

Journal of Neurosurgery, ’02) only 1/38 (3%) had pure CRPS I (RSD) without any other illness.

• 10/38 (26%) had CRPS I (RSD) with nerve entrapment. • 27/38 (71%) had no signs or symptoms compatible with

CRPS I (RSD). They had just nerve entrapment(s).

• Dellon (J Brachial Plex Peripher Nerve Inj. 2009) found, in 40 patients referred for CRPS, 80% had just nerve entrapment.

• CRPS (RSD) is over-diagnosed 71%-80% of the time.

FIBROMYALGIA(Academy of Psychosomatic Medicine .abstract 2010)

• A review was conducted of 38 patients referred with the diagnosis of fibromyalgia.

• The diagnostic criteria for fibromyalgia was not met in 37 of 38 patients.

• Therefore, 97.3% of patients were misdiagnosed by referring doctors as having fibromyalgia, when they did not have it (errors of commission).

• Additionally, referring physicians made only 7/50 diagnoses (including fibromyalgia) that were confirmed by objective testing or diagnostic criteria, which means 86 % of the time they made diagnoses that were not confirmed.

• Referring physicians also failed to diagnose 133 medical conditions that were confirmed by objective testing, for a failure to diagnose rate of 94.3% (errors of omission).

• Of the patients misdiagnosed with fibromyalgia, i.e. told they had fibromyalgia when they did not, 94.2% of them were women.

Fibromyalgia Pain Points

Control

Point

Pain Point

The 18 fibromyalgia pain points of which11 of 18 are neededto establish the diagnosisof fibromyalgia, as longas the pain at the locationis unexplained by someother disease.

Fibromyalgia Criteria and Misdiagnoses

• The patient must have pain in at least 11 of 18 points unexplained by some other disease

• The patient must have disturbed sleep.• The patient must experience chronic fatigue.• Normal blood and laboratory tests.• In 38 patients referred with fibromyalgia, 37 did not

meet diagnostic criteria. 133 other diagnoses were confirmed on objective tests, and explained the pain. (Abstract-Hendler, Murphey and Romero, Academy of Psychosomatic Medicine, 2010)

• The overlooked diagnoses was rate 97%.

Fibromyalgia Pain Points or Something Else?

Control

Point

Acromo-Clavicular JointImpingement

Chondromalacia

Epicondylitis

Lumbar Facet Syndrome

C3-C4 disc

Clavicular-sternal dislocation

Occipital Nerve Entrapment

These diagnoses were confirmed by objective testing in 37 patients misdiagnoses with fibromyalgia.

Thoracic Outlet Syndrome

• This is a very often overlooked diagnosis. • There are two types of thoracic outlet syndrome. • a) Vascular, which is found intra-operatively in

less than 10% of cases (Roos).• b) Neuronal Compression of either lower plexus

or upper plexus or both.• Thoracic outlet syndrome can be a combination

of both vascular and neuro.• EMG/NCV are of no use to establish diagnoses

The Anatomy of Thoracic Outlet

Clinical Tests for Thoracic Outlet

Roos

Adson

Shoulder

Pressure

Vascular Flow Studies Comparing the Roos Maneuver to the Adson for Thoracic Outlet

(same patient as his own control)

Still blood flow with Adson

Blocked blood flow with Roos

Individualized Treatment Plans• No one monomodal program is suitable for all “chronic

pain patients (CPP).”• Using a single modality will produce good results in

some patients, and no results in others. No attempt at diagnosis. All are CPP

• Only through a multidisciplinary diagnostic program do you establish diagnosis, and then tailor the treatment for the disorder.

• Use the www.MarylandClinicalDiagnostics.com tests to get diagnoses and treatment plans which recommend the proper tests to use.

“Flat tire” patients• Concept in physiology: Convergence- multiple

nerves supply a single muscle.• Divergence: a single nerve supplies multiple

muscles.• A single manifestation may have multiple

etiologies-like a flat tire-nail in tread, leaky valve stem, tire off rim or combination of 3.

• A single symptom like pain in last 2 fingers, may be C6-7 disc, thoracic outlet or ulnar nerve entrapment or combination of all 3.

• Treatment plans must focus on diagnosis, consider differential diagnosis, and be individualized.

Patient variables that influence outcomes

• Age• Sex• Ethnic background- Harold Merskey MD• Legal status -active or complete, type of suit• Education or I.Q.• Vocational experience• Pre-morbid personality• Stage of pain -acute versus chronic- 4 stages

Patient Variables in Chronic Pain Determine Outcome

• Non-litigant patients: 6% are exaggerating pain patients (Psychosomatics, ’79).

• LTD patients: 10% are exaggerating (unpublished insurance study).

• Auto Accident and Workers Compensation patients: 13% were exaggerating ( Pain, ’85, J. Occ. Medicine,’88, J. Neurolog & Ortho. Med. & Surgery, ’85, Clinical Neurosurgery, ’89).

Patient Variables-Do they matter?

• In a private clinic study of 120 patients, the average IQ of a litigant patient (Workers Compensation or auto accident) was 93.6 (75-121), (Psychosomatics ’96).

• The average age was 39 (17-70) (ibid).• The average duration of pain was 3.63 years (.1-30).• How do you return to work a 75 IQ, semi-literate truck

driver, with a 10th grade education, with active workers compensation litigation, who is 58 years old, and has arachnoiditis for 3 years causing back pain?

• Patient selection impacts outcome statistics.

Type and Stage of Litigation

• Fact- workers compensation patients out of work for 2 years or more, return to work less than 1% of the time ( Occ. Med, ’68, Occupational Low Back Pain, ’84).

• The current Interpretation of this statistic in Medical Literature is:

• They have “compensation neurosis, secondary gain, financial disincentives, personality flaws, depressive equivalents, unmotivated, using the system.” No-one ever says they are misdiagnosed.

Type and Stage of Litigation• An article in J. of Occupational Med. ’89, compared

83 patients out of work (X = 4.9 yrs.) who had active or complete auto accident litigation or workers compensation litigation-matched for diagnosis

• They found that after proper diagnosis and treatment, there was no difference in the return to work (RTW) rate of patients with active or completed litigation- however-

• Workers compensation patients 19.5% -RTW• Auto Accident patients 62.5%- RTW• Therefore- the type of litigation influenced outcome

Outcome Studies using www.MarylandClinicalDiagnostics.com approach

• Johns Hopkins Hospital reduced their workers compensation cost 54% by making their injured employees see only Johns Hopkins Hospital doctors instead of local community doctors

Bernacki EJ, Tsai SP. Ten years' experience using an integrated workers' compensation management system to control workers' compensation costs. J Occup Environ Med. 2003 May;45(5):508-16.

• The diagnoses of the Diagnostic Paradigm from www.MarylandClincalDiagnostics.com have a 96% correlation with Johns Hopkins Hospital doctors.

Hendler, N, Berzowsky, C and Davis, R Comparison of Clinical Diagnoses to Computerized Test Diagnoses, Pan Arab Journal of Neurosurgery, pp:8-17, October, 2007.

•  

Outcome Studies using www.MarylandClinicalDiagnostics.com approach

• Workers’ compensation patients out of work for 2 years or more had a return to work rate of less than 1%

( Occ. Med, ’68, Occupational Low Back Pain, ’84).

• Using www.MarylandClinicalDiagnostics.com tests on a group of patients out of work for an average of 4.9 years, one clinic had a return to work rate of 19.5% for workers’ compensation patients, 62.5% for auto accident patients, a 90% reduction in use of narcotic medication, and 45% reduction in doctors visits. Hendler, N.: "Validating and Treating the Complaint of Chronic Back Pain: The Mensana Clinic Approach." Clinical Neurosurgery. Vol. 35, Chap. 20:385-397, eds. Black, P., Alexander, E., Barrow, D., et. al., Williams and Wilkins, Baltimore, 1988.

• Cost savings ranged from $20,000 to $175,000 http://www.slideshare.net/DiagnoseMyPain/patient-cost-savings-documented-with-letters

Methods to Avoid Misdiagnosis• See www.MarylandClinicalDiagnostics.com

• The Pain Validity Test can predict, with 95% accuracy, who will have moderate or severe abnormalities on objective medical tests, and can predict, with 85% accuracy who will not (1).

• The Diagnostic Paradigm will give a physician diagnoses which have a 96% correlation with diagnoses of Johns Hopkins Hospital physician (2)

• The Treatment Algorithm list the proper tests to use to confirm the diagnoses, and proper treamtments

(1)Hendler, N. and Baker, A., An Internet questionnaire to predict the presence or absence of organic pathology in chronic back, neck and limb pain patients, Pan Arab Journal of Neurosurgery, Vol. 12, No. 1, pp: 15-24, April, 2008.

(2) Hendler, N., Berzoksky, C. and Davis, R.J. Comparison of Clinical Diagnoses Versus Computerized Test Diagnoses Using the Mensana Clinic Diagnostic Paradigm (Expert System) for Diagnosing Chronic Pain in the Neck, Back and Limbs, Pan Arab Journal of Neurosurgery, pp:8-17, October, 2007.