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• This paper reviews current knowledge of the pathophysiology of complex regional pain syndrome (CRPS) and purported treatments, and provides a modified clinical pathway that attempts to expand the scope of existing guidelines.
• Current guidelines recommend interdisciplinary management using 3 core treatment elements: pain management, rehabilitation ands psychological therapy.
  
• Increasing evidence suggests that some cases are refractory to conservative measures and require flexible application of various treatments and earlier consideration of interventions such as SCS.
• Existing guidelines fail to provide guidance for contingent management in response to a sudden change in the patient's medical status.
• The paper recommends an updated algorithm for the management of CRPS aimed at achieving remission and rehabilitation, which involves concurrent physiotherapy, pain management and psychological therapies.
• The proposed clinical pathway involves several new features, including the use of neurostimulation techniques and consensus guidelines on the timing of more invasive therapies such as regional anesthesia or SCS.
• It is suggested that interventional therapies should be trialed in patients who do not respond to an acceptable level of treatment by 12-16 weeks.

• The aim of this prospective, randomised, controlled study was to determine whether treatment of chronic reflex sympathetic dystrophy with spinal cord stimulation (SCS) and physical therapy is more effective than treatment with physical therapy alone.
  
  
• Patients were 18-65 years old and met the diagnostic criteria for reflex sympathetic dystrophy, established by the International Association for the Study of Pain. Disease was clinically restricted to one hand or foot, affected the entire hand or foot, had lasted for at least 6 months, and did not respond to standard therapy.
  
  
• SCS was tested using a temporary electrode (Medtronic model 3861) connected to an external stimulator (Medtronic model 3625) for at least 7 days. Patients who showed at least a 50% improvement in visual analogue scale (VAS) pain score or a score of at least 6 ('much improved') out of 7 on an effect-of-treatment scale were then given a fully implanted Medtronic Itrel III (Model 7425) spinal cord stimulator using a Medtronic model 3487A electrode.
  
  
• Physical therapy consisted of a standardised programme of graded exercises, designed to improve the strength, mobility and function of the affected hand or foot. This was performed for 30 minutes, twice a week for 6 months.
  

• A total of 54 patients were enrolled, 36 assigned to receive SCS and 18 to physical therapy alone. There were no significant differences in baseline characteristics between the two treatment groups. Test stimulation was successful in 24 of the 36 patients assigned to SCS, and these patients underwent implantation.
  
  
• In patients treated with SCS, the VAS pain score decreased significantly more than for those receiving physical therapy alone (P<0.001). Significantly more patients receiving SCS also reported a score of 6 on the global-effect scale (P<0.001). The treatment did not result in any functional improvement.
  
  
• Four patients developed long-term complications. All resolved with treatment and supplementary surgery. Complications related to unsatisfactory positioning of the electrode in five patients were also resolved by surgery.
  

• The results were obtained in patients with severe reflex sympathetic dystrophy that was unresponsive to standard therapy. They cannot therefore be applied to all patients with this disorder.
  
  
• Functional status of the patients did not improve, possibly because in patients with such severe disability, muscle contractures and atrophy may be so far advanced that functional improvement is unlikely.
  
  
• It was concluded that, with careful selection of patients and successful test stimulation, SCS is safe, reduces pain and improves the health-related quality of life (pain related) in patients with chronic reflex sympathetic dystrophy.
  

• This paper reviews the possible mechanisms by which SCS can control symptoms of CRPS, using the available evidence from a number of clinical studies analysing the use of SCS in the management of CRPS.
  
  
• Evidence indicates that in the majority of patients with severe CRPS Type I, SCS provides sustained pain control and a reduction in the use of narcotics.
  
  
• The main aim of treatment in CRPS is to restore function by a co-ordinated
  approach that uses pain relief, correction of autonomic disturbance and exercise therapy. The author suggests that as time is of the essence, regional anesthesia or neuromodulatory methods to support rehabilitation should be introduced if a patient fails to progress in a timely manner. In some cases, it may be necessary to introduce regional anaesthetic blocks and/or neurostimulation at the start of the treatment algorithm to facilitate the physiotherapeutic measures.

The author concluded that:

• Spinal cord stimulation has proven to be a powerful tool in the management of CRPS.
  
  
• In selected patients who fail to progress using conservative pharmacological or regional anaesthetic measures, SCS may provide sufficient analgesia and restoration of microcirculation in the affected extremity to allow other rehabilitation methods to be effective.
  
  
• Although definitive criteria for the use of SCS have not been established, a trial of neurostimulation is proposed in patients who fail to respond to conservative measures, show a limited response to regional anesthesia and whose symptoms progress over a period of 2-3 weeks.
  
  
• A structured psychological evaluation should be undertaken prior to treatment to ensure that neuromodulation is assured of a positive outcome.
  
  

• This paper presents an algorithm for the management of chronic regional pain syndrome (CRPS).
  
  
• CRPS type I (reflex sympathetic dystrophy) is characterised by clinical features such as regional pain, sensory changes, abnormalities of temperature, sudomotor disturbances, oedema, and abnormal skin colouring occurring after a noxious event. CRPS type II (causalgia) includes these features in addition to a peripheral nerve lesion.
  
  
• The algorithm consists of a progressive series of physical therapies, aimed at achieving remission and rehabilitation.
  
  
• Other treatment modalities, including spinal cord stimulation (SCS), regional anaesthesia, and pharmacotherapy (for example, with non-steroidal anti-inflammatory drugs, opioids, antidepressants or corticosteroids), are used to treat specific signs and symptoms.
  

• The aim of this study was to determine the effectiveness of SCS for the treatment of symptoms associated with reflex sympathetic dystrophy (RSD).

• The study population consisted of 12 patients, all diagnosed with early or intermediate stage RSD. Eight patients had previously undergone surgical sympathectomy, but had suffered a recurrence of pain.
  
  
• Following a successful trial period, all patients received a Medtronic system spinal cord implant, consisting of an Itrel I or Itrel II pulse generator and Pisces-Quadripolar or Resume electrodes. Patients' levels of pain were quantified pre- and postoperatively using a pain questionnaire and visual analogue scale.

• All 12 patients experienced good to excellent relief from the pain associated with RSD.
• At an average of 41 months follow up, all patients were continuing to use their stimulators regularly and only 2 patients required occasional narcotic medications.
  

• SCS is an effective treatment for the pain associated with early to intermediate stage RSD.
  
  
• Ablative procedures for RSD, such as surgical sympathectomy, provide only temporary pain relief and have known physiological consequences. This is not the case with SCS, which demonstrates sustained, effective pain control.
  
  
• The low morbidity of this procedure and its efficacy in patients failing surgical sympathectomy, suggest that SCS is superior to ablative sympatholysis in the management of RSD.

• The aim of this study was to assess the effectiveness of SCS in the treatment of intractable pain due to reflex sympathetic dystrophy (RSD).
  
  
• Eighteen patients with intractable pain due to stage II or III RSD were included in the study. Patients complained of pain in the lower extremities, upper extremities, neck, thoracic wall area and shoulders. All had previously undergone multiple sympathetic blocks and/or surgical interventions for the pain, which had provided only temporary relief.
  
  
• Following a successful trial, 14 patients received a permanent Medtronic Itrel system, using either Medtronic Pisces-Quad or Medtronic Resume electrodes, or a Neuromed stimulation system. In 4 patients, two systems were implanted to cover the more distant areas of the body involved with the disease.
  
  
• Patients were followed up for a period of 4 to 14 months, during which time pain relief was assessed.

• Eleven of the 14 patients experienced good or moderate pain relief with SCS. All these patients felt that the procedure was worthwhile and would undergo it again.
  
  
• All patients who experienced good pain relief stopped or substantially reduced their narcotic intake.
  
  
• In addition to pain relief, the beneficial effects of SCS included a reduction in the swelling of extremities and the subjective normalisation of skin temperature in affected limbs.
  
  
• No transient or permanent neurological damage resulted from the implantation procedure.

• In select patients, SCS alleviates the pain and controls the swelling associated with advanced stages of RSD. If applied at earlier stages of the disease, the success rate and functional improvement may be higher.
  
  
• In this study, effective pain relief with SCS correlates with a reduction in narcotic intake.
  
  
• Considering the unsatisfactory results achieved with sympathetic blocks and/or surgical interventions, SCS may provide a safe and effective alternative for the treatment of RSD.