Article Type : Case Report
Authors : Frank F
Keywords : Chronic pain syndrome; Spinal cord; Hyperalgesia; Allodynia
Background:
Conservative treatment of patients with complex regional pain syndrome (CRPS)
can be challenging and unsatisfactory due to a lack of pain reduction and
dysfunction. CRPS can lead to serious mental health impairment with
catastrophic pain perception. Spinal cord stimulation is a common treatment for
mixed and chronic neuropathic pain syndromes that has been shown to be
effective in early stages of CRPS type I.
Case
Description: We present a case of a young woman with long-term CRPS of her left
wrist. Under conservative therapy, she developed intolerable pain with
catastrophizing pain perception and a desire for distal amputation of the upper
extremity. Even after a prolonged course of disease, she was successfully
treated with cervical spinal cord stimulation.
Conclusion:
SCS is an effective treatment for patients with chronic upper extremity CRPS
that is unresponsive to conventional therapy and should be considered at an
early stage to prevent serious psychological and physical health effects. Even
with long-term CRPS, SCS has positive effects on pain perception, mental
health, and catastrophizing pain perception.
Complex regional pain syndrome (CRPS) is a chronic
pain syndrome that affects the upper and lower extremities and occurs primarily
after trauma or surgery. It is more common in middle-aged women [1, 2]. The
pain intensity is disproportionate to the initial event and is associated with
motor, sensory and autonomic deficits. Clinical diagnosis should be made early
to avoid delayed treatment and is facilitated by the Budapest criteria [3].
Pathophysiology is poorly understood and conventional therapy with pharmacological,
physical and psychological aspects is challenging and applied in an
interdisciplinary environment. Psychological factors and catastrophic
perception can increase stress, aggravate pain and dysfunction [4]. CRPS can
lead to serious mental health impairment and can drastically affect the quality
of life. Interventional methods should be considered if conservative therapy
does not respond within 12 to 16 weeks. However, these surgical measures should
be accumulated gradually in order to prevent further somatization of the
complaints. SCS was first introduced in 1967 and has been shown to be highly
effective in the treatment of CRPS type I with reduction of pain, allodynia,
muscle dysfunction and improvement in quality of life [5]. We present a case of
a young woman with long-term distal upper extremity CRPS type I with
catastrophic pain perception and a desire for an upper extremity amputation who
was successfully treated with cervical spinal cord stimulation. The patient
gave written informed consent.
The patient presented herself to our neurosurgical outpatient department for the first time in May 2019 with increased pain in her left wrist that did not respond to conservative treatment. In 2011, the patient worked as a paramedic and had an accident while working in medical service. The accident caused an avulsion fracture of her left wrist that resulted in several follow-up operations, i.e. 13 surgical procedures, including an arthrodesis of her left wrist, with no lasting effect on pain or function. As a result, neuropathic pain developed in 2015 and a complex regional pain syndrome was diagnosed in November 2016 (Figure 1). The pain symptoms started in her left wrist and spread over to the entire hand and forearm.
Figure 1: Left
picture: Patient´s left upper
extremity after several operations in 2015. The hand was swollen for weeks and
burning pain began at the metacarpophalangeal joint including the thumb. Right
picture: Decrease in swelling of the left hand after lymphatic drainage. Livid
discoloration and marbling of the hand with difference in skin temperature with
up to 4,5°C were present. The pain increased and became unbearable. The whole
hand was affected and became more and more sensitive.
The pain intensity increased with exercises, cold weather, light touch, cold or warm water. An explanation based on other illnesses was excluded. Another surgical, i.e. causal, treatment could also be ruled out. The CRPS criteria were met for persisting pain and for the clinical categories’ hyperalgesia, allodynia, and asymmetry in skin temperature, change in skin colour, asymmetry in sweating, edema, and change in hair growth, decreased mobility, and weakness. In a side comparison, differences in skin temperature of a maximum of up to 4.5 °C were measured. Due to loss of function and persistent pain, she had to train her handedness by being originally left-handed. In professional terms, the patient lost her job in the ambulance service after the arthrodesis in 2015. She began studying in 2017, which she had to finish again due to exacerbated pain and psychological stress. In addition, she developed suicidal ideation in 2015, which took a certain form in 2017 due to a borderline personality disorder. During the presentation in our outpatient department, the pain intensity was rated with a maximum of 10/10 on the visual analog scale (VAS), a minimum of 5/10 on VAS and a pain average of 6/10 on VAS. On the intensity scale of the brief pain inventory 26 out of 40 points were achieved [6]. The pain syndrome was refractory to comprehensive conservative treatment and only 30% of pain reduction could be achieved with previous therapy. A significant influence on mood (7/10), sleep (9/10) and enjoyment of life (7/10) with the brief pain inventory was described. On the pain interference scale, 39 out of a maximum of 70 points were achieved. A total value of 46 (max. 52) was achieved on the pain catastrophizing scale [7]. Clinically, she showed marked allodynia of the distal forearm and the entire hand, accompanied by swelling and changes in skin colour (Figure 2).
Figure 2: Left picture: Patient´s
left upper extremity one week before implantation of the neuromodulation system
in May 2019. Acute swelling, severe burning pain und shiny skin dominated the
clinical appearance. Movement of the fingers was hardly possible. The desire
for an amputation was great at this point. Right picture: Two weeks after the
operation the swelling was completely gone, the skin color was normal, and
movement of the fingers was possible. The pain and sensitivity of the hand
improved significantly.
Motor function tests of the arm and hand could not be
performed in severe pain and arthrodesis with functional disorder of the wrist
and thumb. There was an intense desire for a forearm amputation and a
significantly reduced confidence in medical activities. As a last attempt, we
provided the indication for stimulation of the spinal cord, which could be
carried out in May 2019 eight years after disease progression. The patient underwent
cervical SCS trail using an Abbott Medical Octrode lead (Prodigy MRI™) inserted
at level T8 and ended at level C5. After a successful trial of two weeks, a
permanent implantation of the impulse generator was carried out. During follow
up consultation 12 month later, pain at minimum decreased to 2/10 on VAS with
an average intensity of pain of 3/10 on VAS and a maximum of 6/10 on VAS.
Physical and occupational therapy and psychotherapy were continued as before.
Reduction of pain was rated with 70% with the ongoing stimulation plus
conservative treatment. The intensity scale of the brief pain inventory was
reduced to 14 points (max. 40). Furthermore mood (5/10), sleep (5/10) and
enjoyment of life (5/10) of the brief pain inventory improved with a total of 25
points (max. 70) on the pain interference scale, as well as the pain
catastrophizing scale with a sum score of 18 (max.52) points. Allodynia
decreased with a residual slight presentation combined with a slight
hyperalgesia of the left wrist. Motor function could not be improved due to
arthrodesis. Reduced hairiness and skin atrophy remained. Due to a dislocation,
the generator was revised into a deeper gluteal layer in May 2020. Today, that
means three years later, the patient was satisfied with spinal cord
stimulation, even though she described a slight increase in pain intensity
during winter while consulting our outpatient clinic in March. Pain intensity
was rated with a minimum of 3/10 on VAS, a maximum of 9/10 on VAS and an
average of 5/10 on VAS. On the pain intensity scale of the brief pain
inventory, the patient achieved 22 points (max. 40). Additional to previous
therapy, she was working with a therapy dog. Pain reduction was rated as 50%
with the ongoing treatment. Impact on mood (5/10) was unchanged, sleep (7/10)
worsened slightly, and enjoyment of life (3/10) improved compared to the years
before with an almost stable value on the pain interference scale of 26 points.
Even more, sum score of pain catastrophizing scale was stable (18/52). Despite
the renewed increase in pain, the patient was overall still satisfied with the
neuromodulation and would have it performed again. The patient did not want to
interrupt the stimulation at any time, especially given the positive effects on
quality of life and pain perception. Oral medication could be reduced over the
following years. To avoid habituation effects of stimulation, we recommend
switching between BurstDR™ and continuous mode.
Several studies having shown before that SCS is a safe
and effective procedure for the treatment of pain conditions such as failed
back surgery syndrome, refractory angina pectoris, peripheral vascular disease
and CRPS type I[8,9]. Neurostimulation of spinal cord in patients with CRPS can
reduce pain and improve health-related quality of life in a more effective way
than physical therapy alone [10]. Success depends on strict selection criteria
of patients with complex regional pain syndrome type I, lasting for at least 6
months with a mean intensity >/= 5 on VAS and being not responsive to
conservative therapy. Complications reported after the implantation of a
neurostimulation system were mainly related to hardware problems. In our view,
the low periprocedural risk to patients justifies offering neurostimulation treatment.
Consistent data for long-term efficiency of spinal cord stimulation in CRPS are
lacking so far with reported diminishment between 2-3 years after implantation
on the one hand and a still significant effect on pain reduction after 88
months [11,12]. Best results were seen within one year after implantation in
patients under 40 years and receiving SCS within one year after onset with a
slight decline overtime. For our treatment recommendation of pain therapy, the
factor of time is a very important predictor for a positive response in
patients with chronic pain conditions. Suitable interventions options should be
carried out before irreversible changes in pain memory and irreversible
restructuring processes of central pain take place. The longer the painful
condition persists, the more limited the options for adequate pain treatment.
In comparison to current studies on the successful treatment of pain syndromes
in lower extremity with dorsal root ganglion (DRG) stimulation with a greater
improvement in pain and quality of life, data for upper extremities are missing
so far due to lacking approval for the procedure on cervical spine [13-15].
Notable, in a case report of CRPS in upper extremity, DRG stimulation was
performed accidentally due to an anatomical obstruction on spinal cord with
positive impact on pain reduction [16]. Psychological tests are recommended to
evaluate comorbid psychiatric conditions and dysfunctional cognitions before
implementing medical treatment strategies. Pain catastrophizing and incorrect
beliefs are common in patient with CRPS and may be critically involved in
maintenance of primary features of the pain syndrome and in responses to
treatment. Even though as described before, that psychiatric disorders should
exclude patients from stimulation of the spinal cord, our patient received a
positive effect on psychiatric condition and pain catastrophizing through
neurostimulation. We cannot conclude that pain catastrophizing should be a
contraindication, as similarly reported by Lame. We suggest that SCS is an
effective treatment for disabled patients with severe pain that is unresponsive
to conventional therapy and should be considered in early stages to prevent
severe impact on mental and physical health. Even in long lasting CRPS SCS, as
a minimal- invasive procedure, has a positive impact on pain reduction and
catastrophizing. Its benefit might be underestimated due to lack of larger
studies and should not only be considered as a last chance therapy.
Complex regional pain syndrome in distal upper
extremity can be treated successfully with SCS with no side effects.
Furthermore, neurostimulation has positive effects on mental health and
catastrophic pain perception. We suggest that SCS should be considered early in
the course of disease as a possible therapeutic option for complex regional
pain syndromes in the upper extremity to prevent extremity amputation and major
impact on mental health.
Funding: We
have not received any funding from public or private sources.
Declaration of interests:
The authors report no declaration of interest. The authors alone are
responsible for the content and writing of the paper.