Spinal Cord Stimulators in Neuropathic Pain

Introduction

• Chronic pain is very common

• Immense physical, psychological, societal impact

• Financial burden

Neuropathic pain

• Damage or dysfunction of the nervous system

• Typical symptoms - burning - shooting - allodynia - hyperalgesia

Case history (1)

• Mr X - Referred to the pain clinic

• PC - Right arm pain

• Hx PC - Day 1 post medical procedure - Tingling, weakness, numbness of right arm

Case history (1)

• Investigations - MRI - Nerve conduction studies - Electromyography

• Diagnosis - Brachial plexus injury

• Conservative management strategyEMG

Case history (1)

• Follow up at 6 weeks - Burning, painful to touch, skin discolouration

• Diagnosis - Complex regional pain syndrome (CRPS)

• Therapies in pain clinic - Neurogenic pain medications - Cervical sympathetic block

Case history (1)

SCS inserted 2013

Case history (2)

• Mr FF, 62 yrs - GP referral to pain clinic

• PC - Back pain radiating to both legs

• Hx PC - 20 year history of back pain - Physiotherapy/analgesia - Multiple surgical procedures

Case history (2)

• Diagnosis - “Failed back surgery syndrome”

• Therapies in pain clinic - Neurogenic pain medications - Epidural and facet joint injections - L5/S1 nerve root block

Case history (2)

SCS inserted 2013

Management of chronic pain

Management of chronic pain

Management of chronic pain

Management of chronic pain

Neuromodulation

• Therapeutic alteration of the nervous system

• Electrical or pharmacological

• Implanted devices

Gate control theory of pain

Gate control theory and spinal cord stimulators

History of spinal cords stimulators

Which patients might be suitable for a SCS?

• Failed back surgery syndrome

• CRPS

• Peripheral neuropathy

• Ischaemic limb pain

• Angina

SCS electrodes

SCS electrodes

Components of the SCS

Phases of SCS implantation

1. Assessment phase - appropriate pathology - appropriate patient

2. Trial phase

3. Implantation phase

Where are the electrodes placed?

• Upper extremity T1-T2

• Low back T8-T10

• Lower extremity T10-T12

Trial phase

What are the criteria for a successful trial?

• 50% pain

• Area of parasthesia = area of pain

• Parasthesia not unpleasant

• Functional improvement

Complications of SCS

• Additional revision of the device (23%)

• Hardware malfunction (10%)

• Infection (4.6%)

• Complications during insertion

Some issues for patients….

NICE Guidelines

Case history (1) Complex regional pain syndrome

4 months later

VAS scores 10 3

Some restoration of hand function

Reduction in analgesic medication

Improved mood

Case history (2)Failed back surgery syndrome

2 months later

VAS scores 10 2

Improved mobility

Reduced analgesic medications

Improved mood

Conclusion

• Neuropathic pain is common, some patients are refractory to standard therapies

• Neuromodulation is an alternative method for treating severe, intractable pain

• Excellent results can be achieved with selected patients

Thank You