Medical shockwaves a treatment option for complex and neuropathic pain syndromes?

A compilation of case reports.Kenneth Craig

Medical Director, Kompass OrthoShock Centre for Medical Shockwave Therapy & Research, Auckland.

Introduction

The impervious nature of complex and neuropathic pain syndromes that are often indocile to conventional treatments2,4,5,6 warrants the exploration of treatment methods that limit intrinsic risk while modifying disease patterns.2 This compilation of four case-reports discusses the use of medical shock waves for the treatment of complex and neuropathic pain syndromes of the lower extremity.

Aim

To determine if further investigation is warranted to explore the use of medical shockwaves for the treatment of certain types of neuropathic and complex pain conditions.

Method

Three treatments of medium-low intensity extracorporeal-shockwaves (ESW) propagated by an electro –

hydraulic generator (MediSpec, Germantown) were administered at one week intervals. Energy density

flux levels ranged from 0.08mj/mm² - 0.20mj/mm². Pain, function and emotional measures were

performed utilizing visual analogue scale (VAS), Neuropathic Pain Diagnostic Questionnaire (DN4),

and Pain Outcomes Profile (POP) questionnaire at baseline and post-treatment.

Use of anti-inflammatory and pain medications were ceased prior to treatment and remained discontinued

throughout the 24 week follow-up period.

Result

Improvements in function and stress levels along with reduction of the pain experience was observed post-treatment. Mean average subjective pain scores (VAS) reduced from (baseline 8.87/10 to post-treatment 2/10). Average DN4 (baseline 5.6/10) scored (0/10 post-treatment). POP questionnaire recorded improvements in both the Physical Index (baseline 53.47; post-treatment 2.77), and the Affective Index (baseline 85.49; post-treatment 10.22) respectively.

Discussion

The exact mechanism of ESWT is yet to be fully elucidated, however a dose and stimulus dependant shockwave triggers a neuro-bio-chemical regulatory cascade resulting in the resolution of the associated neuro-physical pathology and cognitive response in the subjects of this case series (Figure 2).

Conclusion

The findings of these case-reports corroborates with the findings of earlier investigations utilizing shockwaves for complex regional pain syndrome of the knee conducted by Nortarnicolaand colleagues (2010). ESW may provide a non-invasive, non-pharmacogenic disease modifying treatment option for periheral neuropathic and complex pain conditions. This encourages further investigations of ESW to be conducted on neuropathic and complex pain syndromes of the upper and lower extremity.

Reference

1. Carmeliet P & Tessier-Lavigne M. Common mechanisms of nerve and blood vessel wiring. Nature. 2005; 436(7048): 193 – 200.

2. Costiga M, Scholz J, Woolf CJ. Neuropathic Pain: A Maladaptive Response of the Nervous System to Damage. Annu Rev Neurosci. 2009; 32;1-32.

3. Craig K & Miller A. Extracorporeal Shockwave Therapy (ESWT), an option for chronic tendinopathy management: a clinical perspective. New Zealand Pain Society Publication. 2011; 8 – 16.

4. Harden R N, Bruel S & Stanton-Hicks M. Proposed New Diagnostic Criteria for Complex Regional Pain Syndrome. Pain Medicine. 2007; 8(4): 326 – 331.

5. Lopes P, Lisboa B, Frattini F, et al. Enhancement of sciatic nerve regeneration after vascular endothelial growth factor (VEGF) gene therapy. Neuropathology and Applied Neurobiology. 2011, 37: 600 – 612.

6. Nortanicola A, Morreti L, Tafuri S et al. Shockwave therapy in the management of CRPS of the femoral condyle of the knee. Ultrasound Med Biol. 2010; 36(6):874-9.

7. Omoigui S. The Biochemical Origin of Pain – Proposing a new law of Pain: The origin of all Pain is Inflammation and the Inflammatory Response. Part 1 of 3 – A unifying law of pain. Med Hyptheses. 2007; 69(1): 70 – 82.

8. Sandkuhler J. Learning and memory in pain pathways. Pain 2000;88: 113 – 118.

9. Sandkuhler J. Models and Mechanisms of Hyperalgesia and Allondynia. Physiological Reviews. 2009; 89(2):707 – 758.

10. Stanton-Hicks M. Complex Regional Pain Syndrome: Manifestations and the Role of Neurostimulation in Its Management. Journal of Pain and Symptom Management. 2006; 31(45): S20 – S24.

Figure 1.

Illustrates a sound wave propagated

electrohydraulically by a controlled underwater

explosion, which is then targeted onto the

region of interest. Ultrasound coupling gel is

used to assist with transmission of the

shockwaves into tissue.

Case Inciting

Event

Disease

Duration

Signs, Symptoms &

Complaint

PreTx

VAS

Hyperalgesia Allondynia Ectopic

activity

Previous Tx. & Working Diagnosis (WDX)

Female

32yrs Trauma 18mths

• Severe Pain

• Mild Inflammation 8.5 Present Absent Present

• Physical therapy

• NSAID’s (WDX: Neuropathic pain)

• Cortisone

Male

56yrs Trauma 48mths.

• Severe Pain

• Feels like standing on

broken glass.

• Inflammation

• Discoloration

• Tropic change (nails)

• >Temperature

• < ROM

• Involvement of

contralateral limb

9.0 Present Present Present

• Physical therapy

• NSAID’s

• Foot orthotics

• Cortisone (1)

• Local block (WDX: CRPS1)4,10

•TENS

• Amitriptylin*

Female

42yrs Trauma 24mths.

• Severe Pain

• Inflammation

• >Temperature

• Unable to weight bear

• Dystonia & weakness

• < ROM

9.0 Present Absent Present

• Physical therapy

• NSAID’s

• Foot orthotics (WDX: CRPS1)4,10

• Cortisone (5)

• GABA**

Female

44yrs Trauma 24mths.

• Severe Pain

• Inflammation

• Discoloration

•Tropic change (nails)

• >Temperature

• Dystonia & weakness

• Required walking aid

• < ROM

9.0 Present Present Present

• Physical therapy

• NSAID’s

• Foot orthotics (WDX: CRPS1)4,10

• Amitriptylin*

Table 1.

Presenting signs & symptoms and treatments

prior to ESWT.

Cortisone (1) – single course.

Cortisone (5) – five courses.

* Treatment discontinued upon patients

request.

** Treatment discontinued due to adverse

reaction.

0

10

20

30

40

50

60

70

80

90

Pre Tx Week 6 Week 12 Week 24

Physical Index

Affective Index

Table 2. Average subjective pain score using VAS demonstrates improvement in pain levels at 24 weeks

from baseline. DN4 scores demonstrates absence of abnormal sensory activity / perception

as of week 12.

Table 3. Average Physical and Affective index scores using POP demonstrates improvements

in each domain respectively at 24 weeks from baseline.

Figure 2. Illustrates the proposed mechanism

of ESW discussed above.

Increases cellular permeability & neuronal

signaling.3,6

Stimulates angiogenesis = improved

microcirculation. Regulates chemical & immuno -

mediators of the inflammatory response (ie nNOS,

eNOS, SP, CGRP, TNFα, IL1B, IL6 etc).3,6

Cellular expression of growth proliferators enhancing

neurotrophic and neuroprotective effects.1,3,6,7

= neural desensitization

& physiological resolution.

Selective erasure of the pathological memory /

response reflex6,8

& resolution of aberrant pain perception.

0

1

2

3

4

5

6

7

8

9

10

Pre-Tx Week 6 Week 12 Week 24

VAS

DN4