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	Pain Therapies
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	Types of Pain
	Chronic Back & Leg Pain
	Complex Regional Pain Syndromes
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	Diagnosis
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Diagnosis

In this section you can find information about the diagnosis of Failed Back Syndrome and of Complex Regional Pain Syndrome.

Causes and symptoms of FBS

FBS can be caused by: [1-7]
	irreversible nerve injury surgical complications psychosocial problems inappropriate selection of patients for surgery recurrent herniation wrong level of operation

Patients with FBS may suffer from: [3,4,8]
	lumbosacral postoperative fibrosis and/or arachnoiditis root lesion dorsal compartment syndrome lateral spinal stenosis

Chronic back and leg pain associated with FBS

Most patients with FBS suffer from mixed back and leg pain, which is often of a
combined neuropathic and nociceptive nature.

FBS always involves the dorsal horn, having central sensitisation and mostly
sympathetic involvement.

FBS consisting primarily of leg pain includes:
	A mixture of nociceptive and neuropathic pain or Neuropathic pain essentially (or primarily) caused by: nerve damage (pre-operation, post-operation and wrong level of operation); epidural fibrosis; lateral spinal stenosis

FBS consisting primarily of back pain is caused by: degeneration of intervertebral joints; pseudoarthrosis, an infection or a degenerative change at other vertebrae; lumbar facet
syndrome; facet joints disc degeneration; lateral spinal stenosis; spondylitis; problems
on another level.

Diagnosis of common conditions leading to low back and/or leg pain

Source of pain	Key characteristics	Clinical examination	Other examinations
Disc degeneration	1. Predominantly located in the low back area, may radiate out to gluteal zone(s) 2. May radiate to lower limb(s), in a non-dermatome distribution 3. Increases during activities that increase strain on the disc, such as sitting, bending or lifting weights 4. Improves when resting or walking around	1. In most cases lumbar flexion is restricted and painful 2. Usually low-lumbar pressure sensitivity 3. No neurological abnormalities or signs of root compression	1. X-rays usually show narrowing of one or more intervertebral spaces; osteophyte growth may be present 2. MRI scans usually show dehydration of the disc
Disc herniation	1. Pain is mostly dermatome-bound and course corresponds to the spinal nerve innervation 2. Sensory disorders in the affected dermatome may be described 3. There may be a reduction in the strength of the muscles associated with the affected nerve	1. Demonstrates neurological abnormalities, such as sensory disorders, weakened reflexes and motor weakness 2. The Lasègue test or femoralis test is usually positive	1. Hernia can be seen on a CT or MRI scan 2. EMG and meticulous neurological examination confirms which root is compressed
Facet joint pain	Pain usually lateral to the midline, often accompanied by discogenic back pain	1. Signs not specific 2. Patients usually feel pain on extension 3. Often paravertebral elective pressure pain in the facet joints	1. Radiological images, particularly the ¾-rotation image, can show the facet joint compression 2. CT scans can show narrowed and hypertrophic facet joints 3. Infiltration of the joint with local anaesthetic and a corticoid preparation, under fluoroscopy or CT support, results in immediate pain relief
Spinal stenosis	1. Signs not specific 2. Patients usually feel pain on extension 3. Often paravertebral elective pressure pain in the facet joints	1. Signs not specific 2. Medical history usually allows a diagnosis to be made	1. Diagnosis suspected if the radiological images show a degenerative antero-/laterolisthesis 2. Diagnosis can be confirmed by a CT scan, MRI or myelography

References
1. Anderson VC et al. Current review of pain 2000;4:105-11
2. Leveque JC et al. Neuromodulation 2001;4:1-9
3. Dario A et al. Neuromodulation 2001;4:105-110
4. Ohnmeiss DD et al. The Spine Journal 2001:358-363
5. Vaccaro AR et al. Spine 2001;26 (24): S111-8
6. Spengler DM et al. Spine 1980;5:356-60
7. Fager CA, Freidberg SR. Spine 1980;5:87-94
8. Long DM. Surgical management of pain 2002: 354-64

Signs and symptoms of CRPS

Sensory	Intense pain [1,2] Hyperesthesia [1,3] Hyperalgesia [1,3] Allodynia [1,3] Sensory deficits e.g. hemisensory impairment [4] Trigeminal hypoesthesia [5]
Autonomic	Swelling [1] Colour and temperature changes [6] Sweating abnormalities [6]
Motor dysfunction	Weakness Decreased range of motion [3] Tremor [1,6] Dystonia [7] Myoclonus [7] Decreased muscular strength, especially grip strength [8]
Dystrophic	Increased or decreased nail and hair growth Skin changes e.g. palor, plantar fibrosis, hyperkeratosis and thin glossy skin [9]

Intense pain and hyperesthesia are the predominant sensory symptoms. The pain, characterized as aching, burning, pricking or shooting, is localized deep in the somatic tissue.

Sensory deficits are common. Rommel et al. observed that 33% of patients had hemisensory impairment with decreased temperature and pinprick sensation ipsilateral to the affected limb. [4]

Trigeminal hypoesthesia has been found in 49% of CRPS patients with upper extremity disease versus <10% in patients with other pain and normal individuals. [5]

The majority of patients describe swelling of the affected limb, which can be aggregated by physical load, painful stimuli and environmental and local temperature changes.

Temperature asymmetry between the affected and unaffected side measured with infrared thermography exceeds 1°C. [3] Such asymmetry can be warmer or colder.

Weakness, tremor and reduced movement are frequently seen.

Zyluk observed that 78% of patients had significantly reduced grip strength. [8]

Range of motion is decreased by joint effusion early in the disease and by contraction and
fibrosis later in the disease. [3]

Tremor has been reported in 24% to 60% of patients. [6,10]

Although dystrophic changes are generally described as occurring late in the disorder, they may appear within weeks of its onset. In some cases, allodynia may be so severe that the extremity is held in a protective posture further accelerating the development of dystrophic changes in both integument and deeper structure


Courtesy of Robert J. Schwartzman, M.D. MCP Hahnemann School of Medicine

International Association for the Study of Pain (IASP) Diagnostic

Type I (Reflex Sympathetic Dystrophy)	Type II (Causalgia)
1. The presence of an initiating noxious event, or a cause of immobilization	1. The presence of continuing pain, allodynia, or hyperalgesia after a nerve injury, not necessarily limited to the distribution of the injured nerve
2. Continuing pain, allodynia, or hyperalgesia with which the pain is disproportionate to any inciting event	2. Evidence of oedema, changes in skin blood flow, or abnormal sudomotor activity in the region of the pain
3. Evidence of oedema, changes in skin blood flow, or abnormal sudomotor activity in the region of the pain	3. This diagnosis is excluded by the existence of conditions that would otherwise account for the degree of pain and dysfunction
4. This diagnosis is excluded by the existence of conditions that would otherwise account for the degree of pain and dysfunction
Criteria 2-4 must be satisfied	All three criteria must be satisfied

References
1. Harden RN et al. Pain 1999;83:211-219
2. Galer BS et al. J Pain Symptom Manage 2000;20:286-92
3. Birklein F, Handwerker HO. Pain 2001; 94:1-6
4. Rommel O et al Pain 1999;80:95-101
5. Thimineur M et al. Clin J Pain 1998;14:256-67
6. Birklein F et al. Pain 1997;69:49-54
7. Schwartzman RJ, Kerrigan J. Neurosurgery 1990;40:57-61
8. Zyluk A. J Hand Surg 2001;26:151-154
9. Wasner G et al. Neuro Clin 1998;16:851-68
10. Sieweke N et al. Pain 1999;80:171-177
11. Stanton-Hicks MD et al. Clin J Pain 1998;15:155-166
12. Merskey H, Bogduk H. IASP Press 1994; pp40-43.