1. Paul ThawleyMSc CLINICAL REASONING
Referred Symptoms
Part 1 aims to give an overview of the clinical diagnostic process based on the orthopaedic medicine principles devised by the late Dr James Cyriax. It is divided into two sections. The first will give an insight into of basic pain theory linking to referred symptoms. Current theories will be explored in an attempt to understand the possible mechanisms for referral, but it is not the intention to give an in-depth study into pain or psychosocial factors and students are encouraged to explore these topics to support their learning. The second section will reflect on the basic principles of clinical examination in order to formulate a clinical diagnosis towards a subsequent treatment plan. The method of subjective and objective examination will be discussed and by reasoned elimination, the tissue in which the lesion lies will be incriminated.
Part 2 will be covered tomorrow and aims to provide insight into mechanisms of injury and repair in order to provide rationalised treatment programmes.

2. All treatment must reach the source
All pain has a source
All treatment must reach the source
All treatment must benefit the lesion
In compiling his system of clinical diagnosis, James Cyriax considered three basic principles to be important, summarised here as:
all pain has a source
all treatment must reach the source
all treatment must benefit the lesion
Although the emphasis here is on pain, the word ‘symptoms’ could equally be substituted for pain in order to give a broader context to the above principles.
In musculoskeletal medicine, focus generally tends to be on the severity or intensity of pain, but we need to be aware of all symptoms described by the patient such as ache, numbness, stiffness, paraesthesia, heaviness, temperature changes etc.
On the whole, the amount of tissue damage is not a reliable predictor of the severity of the pain that will be experienced and symptoms may be accurately localised to the exact site of damage (OA thumb, achilles tendinopathy), may radiate well beyond the site of damage (capsulitis at the hip or shoulder) or be felt in a completely different area to the original damage (diaphragm giving shoulder pain, sciatica, arm pain from cervical spine).
Pain, whether referred or not, is a complex subject.

3. Definition of pain
“An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”
Sometimes pain may have familiar qualities, making it simple to link to certain conditions such as the throbbing pain associated with headaches, the twingy pain of a loose body in a joint or the sharp, lancinating pain particular to lumbar or cervical radiculopathy. However, on the whole, pain is much more complex and has been defined by the International Association for the Study of Pain definition of pain as:
“An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage”
Pain therefore should not be considered to be a primary sensation such as touch, smell or vision, but more as an “emotional state” similar to the feelings of hate, love and sorrow etc. This makes each patient’s pain experience unique and therefore complex to assess.
International Association for the Study of Pain (1980)

4. Frontal lobe Sensory cortex Thalamic relay Temporal lobe
It is not the intention here to present an in-depth study of pain and the following is included by way of revision of basic pain mechanisms which may give us an insight into why pain may be referred and to support its sensory and emotional aspects.
The afferent nociceptive system delivers impulses to the spinal cord by relatively slow conducting A delta fibres which are the first or fast pain fibres (producing well localised sensations of sharp pain) and by the C fibres, the second or slow pain fibres (producing diffuse pain sensations, poorly localised and persistent (analogy - sprained ankle, acute localised pain first, followed by duller diffuse pain)
The dorsal horn is the first site for processing all incoming sensory information from the same segmental level. Impulses cross the spinal cord to be relayed through the anterolateral tracts and the thalamic relay to various aspects of the brain.
Anterolateral tracts pertinent to this are:
Spinothalamic tract (STT) seems to be a direct nociceptive pathway with projection onto the sensory cortex where the sensory dimensions of pain are processed, sensory cortex has body map for localisation of symptoms to specific segments, also provides information about intensity and quality of pain
Spinoreticular tract (SRT) seems to be an indirect multi-synaptic pathway with projections to many regions of the brain, each contributing a specific component to the global experience of pain. May involve:
Frontal lobes and limbic system: associated with emotional aspects of pain such as anxiety and fear, something only ‘hurts’ when the sensation reaches the frontal lobes. No body map, poor localisation, associated with emotional distress
Hypothalamus - psychological influences, responsible for an autonomic response to pain such as increased BP, irregular breathing or evoking a visceral reflex e.g. gastrointestinal effects associated with the experience of pain such as a ‘sickening pain’
Temporal lobe: responsible for recent and long term memory storage, recall of a painful experience depends on the length of time, not the severity of the painful experience
However, things are not that simple and peripheral and central pain modulation systems may be responsible for the variation in intensity of pain felt in patients with comparable lesions and for variation in pain intensity in the same patient associated with mood, concentration on the problem or on suggestion from others
Temporal lobe
Adapted from Ombregt et al 2003
Ombregt et l 2003

5. Multidimensional aspects of pain
Sensory: physical qualities, intensity, location
Emotional: fear, anxiety, anger, worry
Cognitive: thoughts about pain - how bad is it, what to do about it
Social factors: family, work, cultural, past experience
Remembering back to the international definition of pain as a sensory and emotional experience - all pain is real but multidimensional aspects of pain make it difficult to interpret. Account needs to be taken of physical factors (the sensory dimension) and emotional factors (the affective dimension) including thoughts about pain (the cognitive dimension). Sometimes one of these factors maybe more dominant than the other.
Sensory aspects inform us about the physical qualities and location of the symptoms. Whether it is an acute twinge, a mild or deep ache, sharp pain, minimal discomfort, soreness, stiffness etc… Location of symptoms allows us to ‘map’ the symptom (s) to a specific area of the body. Is it linked to specific dermatomes, can it be accurately located by the patient, is it widespread and unspecific, are questions that may need to be considered.
Emotional aspects may influence the patient’s response to pain. Emotional words such as it’s agony, miserable or unbearable give verbal clues to the emotional state. This may manifest itself as fear, anxiety, anger, worry or indeed psychological distress. A hostile and doubting environment can increase anxiety, stress and self doubt, whilst a caring, supportive environment may reduce emotional upset, re-enforce self esteem and may instil positive coping behaviours that maintain function.
Cognitive aspects of pain involves the patient’s thoughts associated with their painful experience – how bad is the damage and perhaps what to do about it? It may involve the patient making a change in behaviour, which could be by way of a shout, moan or grimace. A change in posture maybe adopted conveying to others that assistance or support is required, particularly of close relatives. Work arrangements may have been modified, the patient may rest, ignore it or work through it. Extreme circumstances - battlefield injuries or injuries occurring in sporting competitions where the pain is not felt till later.
Social factors family dynamics, work situation, cultural and/or religious expectations may influence pain behaviour which may be seen clinically as the extremes from the stoical (British stiff upper lip) to the catastrophizer (associated with the middle east). Duration of symptoms may be linked to the memory of pain possibly influencing future pain experiences.

6. Referral -possible mechanisms
Convergence-projection Theory
The evidence for why pain is referred from the deeper structures is pretty scant. Most work seems to be associated with visceral pain which is frequently localised to the surface of the body within the relevant dermatomes.
A possible explanation for referred pain could be the projection-convergence theory of Ruch (1946) discussed in Strong et al 2002, which suggests that all nociceptive input from deep and superficial tissues (visceral and neuromusculoskeletal) of the same embryonic segmental origin converges onto common neurons in the dorsal horn of the spinal cord and as there are no ascending spinal pathways dedicated to transmitting separate information from the viscera, confusion may therefore occur in shared ascending pathways.
No slide for the following, but could be mentioned if deemed appropriate:
Another explanation may be associated with complex up-regulation of the central and peripheral nervous system. Peripheral sensitisation in which a response to tissue damage is heightened by the chemicals in the ‘inflammatory soup’ in the area of damage. Central sensitisation which is a complex up-regulation of the nociceptive system following soft tissue or nerve damage. Increased excitability of the neurons in the dorsal horn leads to an expanded receptive field and pain referred beyond the area of the original injury. This development of referred pain may rely on the intensity and duration of the initial stimulus, the greater the initial stimulus, the larger the area and intensity of the remote referred pain site (Arendt-Nielsen et al 1999 in Strong et al 2002)
Strong et al (2002); Ombregt et al (2003)

7. Referral -possible mechanisms
Heart C3 - T5
Gall bladder T9
Testicle T11 - L1
Diaphragm C3 - 5
Latissimus dorsi C6 - 8
Gluteal muscles L5 - S2
Another explanation may be that many of the viscera migrate away from their area of embryonic origin during development resulting in pain being referred to locations remote from the site of pain e.g.:
Heart is derived from endoderm in the neck and upper thorax C3-T5 (NB according to Strong et al), pain due to cardiac ischaemia is felt in the dermatomes C3-T5 i.e. left shoulder and arm pain
Gall bladder T9, pain felt below tip of right scapula
The testicle is supplied by T11- L1, but underlies the S4 dermatome where pain may be felt locally or can be referred to the lower thoracic or upper lumbar regions.
The explanation for referred visceral pain can be applied to musculoskeletal structures. The dermatomes generally extend further than their underlying myotome and sometimes muscles become completely dissociated from their covering dermatomes e.g. C5 segment in the upper limb, the myotome does not extend beyond the elbow, but the C5 dermatome extends to the base of the thumb.
Sometimes muscles migrate e.g. diaphragm C4 - pain felt at the tip of the shoulder, lat dorsi C6-8 segments but those dermatomes don’t even occupy the trunk so lat dorsi is completely dissociated from its dermatome.
The gluteal muscles are supplied by L5 - S2 but underlie L1-3 dermatomes.

8. Referral -possible mechanisms
Error in perception (Cyriax, 1984; Kesson and Atkins 2005)
According to Cyriax (1983) referred pain is due to an error in perception. Throughout life the sensory cortex receives sensory information from the skin, the skin is the tissue of which we are most aware. When the sensory cortex receives sensory information from the skin or superficial tissues it interprets those sensations accurately, referring pain to the local area from which the sensations were received. If the sensory cortex then receives sensory information from the deeper tissues e.g. the spinal, hip or shoulder joints, these are tissues which do not normally send sensory information to the cortex and the cortex interprets them on the basis of past experience. That is, to refer the pain to an area of skin (the dermatome) connected with those particular cells in the cortex producing a vague, dull, deep pain or ache, poorly localised, but perceived to be felt under a widespread area of skin. Non verbal communication can often be helpful here, if the patient uses the whole hand to map out an area of pain, this may be considered to be referred pain and you may judge it to be necessary to eliminate the more proximal joints as a possible cause of referral. If the patient can accurately localise the pain using the pointed finger, a decision may be made to apply examination of the local examination only.

9. Referred symptoms may be
Somatic
visceral: deep, not well localised
musculoskeletal: deep, not well localised
Neuropathic: continuous, burning, lancinating
Psychological (biopsychosocial model): not well localised

10. Central somatic and neurological structures
Central, central unilateral or bilateral symptoms
Referred over many segments (multisegmental)
Proximal and/or distal referral
This is a general look at central somatic and neurological referral - will look at specific structures in a minute.
Central somatic and neurological structures
Central, central unilateral (i.e. buttock or scapular pain), bilateral symptoms (i.e. bilateral leg pain from lumbar dural irritation)
referred over many segments i.e. multisegmental - because the central canal structures are supplied by the sinuverebral nerve - can give discussion on this here
proximal and/or distal referral (e.g. lumbar dural/central pain may radiate up to inferior angles of scapulae and into both legs; cervical dural(central) irritation can radiate to inferior angle of scapulae and into head)

11. Multisegmental Reference
Examples of multisegmental (extrasegmental) reference of symptoms
cervical
thoracic
lumbar
Ombregt et al 2003

12. Unilateral somatic and neurological structures
Unilateral, segmental (dermatomal) referral
Generally refers distally
Occupies all or part of a dermatome
This is a general look at unilateral somatic and neurological referral - will look at specific structures in a minute.
Unilateral, segmental or dermatomal referral
Generally refers distally
occupies all or part of the dermatome depending on the strength of the stimulus

13. In order to understand basic patterns of referral it is necessary to consider how the dermatomes develop and to revise the patterns of dermatomal reference.
At about 4-6 weeks, the developing foetus undergoes segmentation into blocks of cells called somites which in turn differentiate into the myotomes which form the skeletal muscles, the dermatomes which form connective tissues including the skin and sclerotomes which form the axial skeleton.
The dermatomes and sclerotomes are supplied by the somatic sensory neuron of one spinal nerve, whilst the muscles are innervated by the somatic motor neuron of one spinal nerve.
As a general rule – the dermatomes tend to project further distally than the underlying myotomes.
Netter 1997

14. C1 - Top of head
Conesa & Argote 1976

15. C2 – side and back of head, upper half of ear, cheek and upper lip, nape of the neck
C3 – entire neck, lower mandible, chin, lower half of the ear

16. C4 – epaulette area of the shoulder

17. C5 – anterolateral aspect of the arm and forearm as far as the base of the thumb

18. Anterolateral aspect of the arm and forearm, thenar eminence, thumb and index finger

19. C7 – posterior aspect of the arm and forearm, index, middle and ring fingers

20. C8 – medial aspect of the forearm, medial half of the hand, middle, ring and little fingers

21. T1 – medial aspect of the forearm, upper boundary uncertain

22. T2 - Y-shaped dermatome, medial condyle of humerus to axilla, branch to sternum and branch to scapula
T3 – area at front of chest, patch in axilla

23. T4 – circling trunk above nipple area
T10 – circling the trunk, roughly above umbilicus
T11 – circling trunk, roughly below umbilicus

24. T4,5,6: circling trunk above, at and below the nipple area (Fig. 1.1l)
T7,8: circling trunk at lower costal margin (Fig. 1.1l)
T9-11: circling the trunk, reaching the level of the umbilicus

25. L1: lower abdomen and groin, lumbar region between levels L2 and L4, upper, outer aspect of the buttock

26. L2: two separate areas: lower lumbar region and upper buttock whole of the front of the thigh

27. L3: two separate areas: upper buttock, medial aspect and front of the thigh and leg as far as the medial malleolus

28. L4: lateral aspect of the thigh, front of the leg crossing to the medial aspect of the foot, big toe only

29. L5: lateral aspect of the leg dorsum of the whole foot first, second and third toes, inner half of the sole of the foot

30. S1: sole of the foot, lateral two toes, lower half of the posterior aspect of the leg

31. S2: posterior aspect of the whole thigh and leg, plantar aspect of the heel

32. S3: circular area around the anus, medial aspect of the thigh
S4: saddle area: anus, perineum, genitals, medial upper thigh
S5: coccygeal area

33. Could change the pace now by stopping to give students an activity of completing the appropriate dermatome activity sheet in workbook - may want to use flash cards as well, but timing here is crucial - don’t want to end up rushing the last bit.

34. Factors Influencing Referral of Symptoms
Strength of stimulus
Position in the dermatome
Depth
Nature of the structure
In general terms, referred symptoms may be influenced by the following factors:
Strength of the stimulus: Symptoms are referred depending on the strength of the stimulus. For example a chronic shoulder or hip capsulitis may produce a vague referral of pain part way into the dermatome - the shoulder to the upper arm, the hip to the knee for example whilst an acute capsulitis may refer pain throughout the whole dermatome, the shoulder to the base of the thumb (C5 dermatome), the hip to the medial malleolus (L3 dermatome). A small, central disc lesion may produce a central short reference of pain, whereas a large central lesion may produce widespread extrasegmental pain.
Position in the dermatome: a structure placed at the proximal end of its dermatome has the potential to refer symptoms over a greater distance e.g. the hip joint may refer symptoms to the medial malleolus, the distal end of the L3 dermatome, the C7 nerve root, paraesthesia to the middle three fingers, the distal end of the C7 dermatome. The distal structures found around the wrist and ankle produce very little referral of symptoms as they are superficial structures placed at the distal end of their dermatomes.
Dept of the structure: Deep structures tend to confuse and give more referral of symptoms, which was the opinion of Cyriax (1984) and also the finding of Kellgren (1939). Patients may have difficulty in localising symptoms from the deeper seated structures and may indicate the symptomatic area by using the whole hand. Superficial structures tend to give a more accurate localisation of the lesion and patients are more able to indicate the site.
Nature of the structure: different tissues have different degrees of sensitivity which will also influence their patterns of referral of symptoms which will now be discussed further:

35. Nature of the Structure
Central somatic e.g. dura mater, PLL, disc
referral of multisegmental pain
referred tenderness
Dura mater, PLL and intervertebral discs are central structures which produce multisegmental (extrasegmental) pain dependent upon the strength of the stimulus.
Probably due to their innervation by the sinuvertebral nerve

36. Nature of the Structure
Central neurological structures e.g. spinal cord
no pain
multisegmental reference of paraesthesia
upper motor neurone lesion
No pain
multisegmental reference of paraesthesia (bilateral hands and/or feet)
upper motor neurone lesion - spastic muscle weakness, increased reflexes, spastic gait, extensor plantar response (Babinski)

37. Nature of the Structure
Unilateral somatic structures e.g. bone and periosteum, ligament, tendon, muscle, joint capsule, bursa
segmental reference of pain
depends on strength of stimulus, position in dermatome, depth
E.g. bone & periosteum,ligament, tendon, muscle, joint capsule, bursa
segmental reference of pain
depends on strength of stimulus, position in the dermatome, depth of the structure
Kellgren (1938, 1939) observed patterns of referred pain induced by the injection of 6% hypertonic saline into deeply placed structures including muscle, tendon sheaths, fascia, periosteum and interspinous ligaments. Injecting muscle produced diffuse referred pain which appeared to follow a segmental pattern. Tendon sheath and fascia gave sharply localized pain. Stimuli did not produce pain from articular cartilage or compact bone but when applied to cancellous bone a deep diffuse pain was produced.
Witting et al (2000) compared local and referred pain following intramuscular capsaicin injection into the brachioradialis muscle and intradermal injection in the skin above the muscle. Intradermal injection produced more intense, localized pain whereas the intramuscular injection produced deeply located pain as well as referring to skin.
Inman & Saunders (1944) noted a variability of sensitivity to the different structures beneath the skin, creating a ‘league table’ of those tissues with the highest sensitivity to the least, as follows: bone, ligaments, fibrous capsules of joints, tendons, fascia and muscle. These findings were supported in part by Kuslich et al (1991), who investigated tissues in the lumbar spine as potential sources of low back pain, using progressive local anaesthetic during operative exploration of the spine. Their emphasis too was that muscles, fascia and the periosteum and compact layer of bone (they did not test cancellous bone) were relatively insensitive.

38. Nature of the Structure
Unilateral somatic structures e.g. dural nerve root sleeve
segmental reference of pain in all or part of the dermatome
greater the compression, the more distal the pain
no edge or aspect
E.g. dural nerve root sleeve
segmental reference of pain in all or part of the dermatome on compression of the structure, depends on strength of stimulus
great the compression, the more distal the reference of pain
no edge or aspect

39. Nature of the Structure
Unilateral neurological structures e.g. nerve root
compression phenomenon
segmental reference of paraesthesia
no edge or aspect
lower motor neurone lesion
may become pain sensitive
E.g. nerve root
"compression phenomenon" (Cyriax, 1982)
segmental reference of paraesthesia at the distal end of the dermatome
no edge and no aspect
lower motor neurone lesion with flaccid weakness
absent or reduced reflexes
may become pain sensitive – sharp, lancinating
? Why - maybe associated with mechanical 9compression), inflammatory and/or ischaemic factors
(consider combined states i.e. compression of the nerve root through the dural nerve root sleeve may give a mixed pattern of somatic and neuropathic pain)

40. Nature of the Structure
Unilateral neurological structures e.g. nerve trunk
release phenomenon
onset related to time of compression
deep, painful paraesthesia
some aspect, no edge
E.g. nerve trunk
"release phenomenon" (Cyriax, 1982)
onset related to the length of compression time
deep, painful paraesthesia in cutaneous distribution of the nerve trunk
some aspect, no edge egs: lower trunks brachial plexus in upper limb (thoracic outlet syndrome), sciatic nerve trunk compression in lower limb

41. Nature of the Structure
Unilateral neurological structures e.g. peripheral nerve
numbness in cutaneous distribution of nerve
edge and aspect
E.g. peripheral nerve
numbness
edge and aspect egs: median nerve in upper limb, lateral cutaneous nerve of thing in lower limb (meralgia paraesthetica)

42. General rules of referred psychological symptoms
Generally associated with chronic pain states
Not well localised
Inconsistent signs and symptoms
The IASP definition we discussed earlier alerted us to pain as a sensory and emotional experience. As well as the pathophysiological changes contributing physical factors to the to the pain experience, account must be taken of psychological factors which contribute emotional factors and well as environmental influences (loss of job, single parent etc) which contribute social factors. Put together, all this has a powerful impact on pain perception generally, but in particular in chronic states. However, as already stated, this is not intended to be an in-depth study of pain and you are referred to the various texts that deal with this subject in more detail.
In keeping thing simple - link to next slide

43. Medical Model Pathology Symptoms Treatment
The traditional medical model involves some kind of pathology, which produces symptoms, the history and examination establishes a diagnosis and if the appropriate treatment is applied we end up with a happy patient!
Ask the students what they think about this model and if their patients conform to this? Allow time for a brief discussion which hopefully will establish that most patients are more complex!
Patients may indeed adhere to this model, but in general it is not that simple, this may lead to discussion about other aspects of pain linking to the above, and treatment goals will need to address all components of the patient’s painful experience.
Treatment

44. Biopsychosocial Model
Psychosocial Factors
Biology
Biopsychosocial Model reference to the work of Waddell, Maine, Butler, Gifford etc
Big biology, little psychosocial factors - focus of treatment is on the biology i.e. the physical problem
Although the emphasis of treatment here would be on physical factors, any associated psychosocial factors can also be addressed - acute pain associated with anxiety for example

45. Biopsychosocial Model
Psychosocial Factors
Small biology - big psychosocial factors - focus treatment on the psychosocial factors rather than the physical - most pertinent to chronic pain states. Assess for ‘yellow flags’, chronic pain associated with suffering, illness behaviour, sick roles, signs of distress - after the consultation, a measure of how depressed a patient is is the way the consultation has made you feel.
Shift the emphasis from symptomatic treatment to rehabilitation and self-management strategies.
Education: Directed primarily at overcoming fear avoidance beliefs and encouraging patients to learn to manage and take responsibility for their own self-care (for example The Back Book).
Reassurance and advice: Strong reassurance and advice to stay active.
Exercise: An active, progressive exercise and physical fitness programme.
Pain management: Behavioural principles of pain management
Work: In an occupational setting and directed strongly towards return to work. Joint employer-worker initiatives to provide optimum management and to facilitate and support workers remaining at work or returning to work as early as possible may reduce sickness absence.
Rehabilitation: May also include some symptomatic relief measures, but if so these should supplement and reinforce, and must not interfere with the primary goal of rehabilitation.
OCCUPATIONAL HEALTH GUIDELINES FOR THE MANAGEMENT OF LOW BACK PAIN AT WORK (2000) (relates to low back pain)
Biology

46. Psychosocial Factors (yellow flags)
No recognisable pattern
Poor co-operation
Seeks answer expected
Contradictory signs
‘Juddering’ Beware the bizarre, but consistent patient
In orthopaedic medicine, the term ‘psychogenic pain’ has traditionally been used. However, pure psychogenic pain is rare and has no known underlying physical cause (although it may be used as a cop out if the condition does not seem to fit a medical model), the patient may have signs of pain caused purely by psychological mechanisms. In reality most pain presents with psychological and physical symptoms and the more modern term of biopsychosocial is now more commonly used.
Assessment for psychosocial factors is to screen for the so called ‘yellow flags’ (Waddell 1998). In terms of orthopaedic medicine these could include:
no recognizable pattern of signs and symptoms (to fit with a medical model)
poor co-operation on the behalf of the patient
patient seeks the answer expected from the clinician
mutually contradictory signs - the resisted tests in the objective examination are most helpful here
juddering on resisted testing - which will be expanded on in part 2
However, one word of caution - beware of the bizarre, but consistent patient - psychosocial influences tend to produce a changing picture of signs and symptoms, rare conditions may not seem to fit a medical model, but on the whole they present with consistent signs and symptoms.