Category Archives: Phantom Limb Pain

Restoration of Sensation May Lead to Reduced Phantom Limb Pain in Amputees

Dear Pain Matters blog readers,

Biomedical engineers at the Case Western Reserve University, Cleveland, Ohio, have (unwittingly) reduced/eliminated phantom limb pain in 2 amputees with severe phantom limb pain while also restoring sensation across both hands via novel ‘prosthetic system’ treatment.


Source:   Case Western Reserve University, Cleveland, Ohio

Prior to prosthetic system treatment to help restore sensation, both men were unable to feel their hands.  Both men had also suffered from phantom limb pain. 

Post-prosthetic system treatment, both patients gradually began to feel familiar sensations again.

Both patients were also able to ‘feel’ their hands for the first time since their accidents, and this helped them control their prosthetic hands better.

Restoration of Sensation and Possible Reduction of Phantom Limb Pain via Novel Prosthetic System Treatment:

Electrode cuffs (2-3) that encircle major nerve bundles were surgically implanted into both patients’ arms.  These electrode cuffs enabled the patients to feel 16-19 distinct ‘contact points’.

The sensory nerves were stimulated via unique and changing patterns and intensities of electrical signals that were sent to the 16-19 distinct ‘contact points’ on the electrode cuffs.  Different signal patterns (transmitted to the electrode cuffs via the prosthetic system) are interpreted as different feelings by the brain.  This can lead to the restoration of certain sensations.

For example, certain patterns and intensities of electric signals may evoke the feeling of cotton, while other electrical signal patterns may feel like ‘water running across the back of a hand’, sandpaper, a smooth surface or even a ridged surface.

An unexpected positive outcome from this prosthetic system treatment was that, after 2 years of testing, the phantom limb pain was gone.

The 2 Patients:

(1) The first patient, Mr Spetic, lost his right hand in an industrial accident 4 years earlier.  He suffered phantom limb pain since the accident.  Quoting Mr Spetic (in the video):

‘The way I described it was:   My hand was in a vice and crushed, and it kept on going and going.’

Following experimental prosthetic system treatment whereby a computer algorithm sent certain patterns of electric signals into the nerves, Mr Spetic said that his phantom limb pain subsided.  Quoting Mr Septic (in the video):

‘Just about, I’d say, 90-95% gone.’

(2) The second patient, Mr Vonderhuevel, who had phantom limb pain following the loss of his right hand and part of his forearm in an accident, said that his phantom limb pain was ‘nearly gone following experimental prosthetic system treatment.

Credit:   Case Western Reserve University, Cleveland, Ohio 


Targeted restoration of sensation via prosthetic system treatment may lead to significant reduction, and even elimination, of phantom limb pain for some phantom limb pain sufferers.  This offers hope to amputees with pain.

Sabina Walker


(1) Amputees discern familiar sensations across prosthetic hand

(2) Prosthetic hands endowed with a sense of touch; Elizabeth Pennisi; 8 October, 2014

(3) Thomson, H.

Once more with feeling

New Scientist, Volume 224, Issue 2991, 18 October 2014, Pages 8–9





‘Pokémon Go-style’ Pain Management?

Dear Pain Matters blog readers,

‘Augmented reality’ not only forms the basis for Pokémon Go for entertainment, but it may also offer novel treatment for some patients with phantom limb pain.

Phantom limb pain is very common in amputees affecting up to 70% of all people who have lost a limb.

A successful case study involving augmented reality:

A 72-year old man suffered moderate to unbearable phantom limb pain since the loss of his arm below his elbow joint in 1965 caused by traumatic injury.  Since the amputation, this patient lived with constant burning pain that changed hourly, ranging from ‘3’ (on a scale from 0 – 10) to ‘excruciating pain levels’.  He also awoke nightly as a result of intense episodes of pain.

Conventional pain treatment failed him, and for almost half a century, he was never completely free of pain.

After 48 long years of severe phantom limb pain, and following experimental treatment involving augmented reality and gaming, this man finally found significant pain relief.  Using the myoelectric signals (‘myoelectric  pattern recognition’) at the arm stump, it was now possible to volitionally and directly control the ‘virtual arm’ (through the prediction of motion intent).  This in turn resulted in reduced phantom limb pain (Ortiz-Catalán et al, 2014).

Specifically, augmented reality pain treatment involved:

  • ‘Projection of a virtual reality arm’ from the patient’s painful limb stump –
    • This virtual arm was superimposed onto the patients’ painful limb stump (to resemble a real arm) on the computer screen;
  • Real-time recording of muscle signals from the painful arm stump –
    • This recording of residual electrical signals in the muscles via electromyography (EMG) is done via electrodes on the skin of the arm stump; and
  • Conversion (via software using complex algorithms) of the electrical signals from muscles in the arm stump –
    • The converted data was used to control specific movements of a virtual arm in augmented reality.
    • Specifically, the patient was able to imagine driving a car by ‘moving’ his virtual arm (that represented his missing arm) on the computer screen.  This enabled him to control his superimposed virtual arm in real-time during a computer car racing game.


A YouTube video and 2 photos are provided below for further details:

Please note:  Audio is not available for this YouTube. 



Above, photo #1:

The patient can see his virtual arm that is now superimposed onto his missing arm on the computer screen.  The patient can control his virtual arm via converted residual muscle signals arising from his arm stump.


Above, photo #2:

(A) Surface electrodes on the arm stump

(B) See first photo (above)

(C) Patient playing a computer car racing game by imagining ‘moving his missing arm’ to drive a car.  Specifically, the patient imagines specific and/or random arm movements, as requested by the computer during the car racing game.

(D) Patient using the ‘Target Achievement Control’ test for rehabilitation.

Credit (YouTube video and photos):   Ortiz-Catalán et al, Frontiers in Neuroscience


The patient stated that his pain was drastically reduced, albeit slowly, over 18 weeks.  He even enjoyed nil pain during some of his augmented reality treatments, and he no longer wakes up at night due to intense pain.

Quoting the patient:

“These pain-free periods are something almost new to me and it is an extremely pleasant sensation.” 

Quoting the patient’s wife:

“My husband can live 10 years more than I expected, as pain now plays a less important role in his life and those close to him can see it.”

(Ortiz-Catalán et al, 2014)

The patient also said that his phantom (missing) hand, that was painfully clenched in a permanent posture for 48 long years, was now ‘open and relaxed’ following augmented reality treatment.

Given that the electrical signals are obtained from the arm stump, this may indicate that the arm stump itself is driving the chronic and severe phantom limb pain suffered by the patient for 48 years.  Hence, in this particular patient, the phantom limb pain appears to be peripherally-induced (not centrally-induced).

Quoting Max Ortiz Catalán:

“…the control signals are retrieved from the arm stump, and thus the affected arm is in charge…The promotion of motor execution and the vivid sensation of completion provided by augmented reality may be the reason for the patient improvement…”

(Chalmers University of Technology, 2014)


Max Ortiz Catalán, Assistant Professor

Chalmers University of Technology, Gothenburg, Sweden.


Ortiz Catalán and his team are optimistic that pain therapy involving augmented reality and gaming may offer hope for some phantom limb pain patients including bilateral amputees with phantom limb pain.  This new augmented reality/gaming treatment may also be a lot more fun and engaging than conventional pain treatments, hence encouraging increased patient compliance.

A follow-up multi-center clinical trial, led by Chalmers University of Technology, and performed at 4 hospitals, being:

  • Sahlgrenska University Hospital, Gothenburg, Sweden;
  • Örebro University, Örebro, Sweden;
  • BräckeDiakoni Rehabcenter Sfären, Stockholm, Sweden; and
  • University Rehabilitation Institute, Ljubljana, Slovenia,

was recently completed to assess the potential efficacy of augmented reality pain therapy for patients with chronic, intractable phantom limb pain.

We can expect some exciting results!  (Watch for an upcoming paper by Ortiz Catalán et al.)

Ortiz Catalán and his colleagues also helped implement augmented reality pain treatment in clinics in Belgium, the Netherlands, Slovenia and Japan (with Austria and Latvia to follow) for selected phantom limb pain patients who are refractive to other pain treatments.

Lower limb amputees with phantom limb pain are now included in the clinical trials.

(Source:   Email dated 3 August 2016 from Assistant Professor Max Ortiz Catalán.)

This is great news for all phantom limb pain sufferers!

Sabina Walker

PS Quoting from Assistant Professor Max Ortiz Catalán’s email dated 3 August 2016:

“You are welcome to encourage patients and clinicians to contact me if they would like to try this technology.  It’s non-invasive and safe so it poses little to no risks.  They can contact me at this e-mail:

Thank you again for your interest in our work.”


Media Releases:

(1A) Lewis, Tanya; Staff Writer, Live Science

Virtual Reality Treatment Relieves Amputee’s Phantom Pain

25 February 2014

(1B) Chalmers University of Technology

Phantom Limb Pain Relieved When Amputated Arm Is Put Back To Work

25 February 2014

Peer-Reviewed Papers: 

(2) Ortiz-Catalán M, Sander N, Kristoffersen MB, Håkansson B and Brånemark R (25 February, 2014)

Treatment of phantom limb pain (PLP) based on augmented reality and gaming controlled by myoelectric pattern recognition: a case study of a chronic PLP patient.

Front. Neurosci. 8:24.

Includes Supplementary Material – Video (audio unavailable)

doi: 10.3389/fnins.2014.00024



Ziconotide (Prialt) for Nerve Pain Including CRPS?

Dear Pain Matters blog readers,

For some pain sufferers, pain relief may be offered (in part or in full) by a component of the venom of an ocean-dwelling cone snail called Conus magus.

Before continuing, I would like to take a moment to celebrate the beauty, power, and energy (while also respecting the dangers) of our oceans with all its amazing creatures (including, of course, deadly cone snails).  I took this photo from BELOW the ocean waves (while snorkelling yesterday).


Today’s blog post is on Ziconotide (Prialt).  Ziconotide is the synthetic equivalent of a naturally-occurring conopeptide called SNX-111 (or omega-conotoxin MVIIA), a component of the venom of the marine cone snail, Conus magus.

Ziconotide, a novel non-opioid drug, can be used to treat patients with severe chronic pain.  It works by selectively and potently blocking the neuronal N-type calcium channel.

Some patients with severe chronic pain may receive significant pain relief from Ziconotide, either as sole treatment (monotherapy) or with other treatments.  Ziconotide is able to maintain its analgesic effects for month(s), even after a single infusion treatment.

Ziconotide treatment does not result in tolerance, dependence, nor respiratory depression (unlike opioids).  However, there can be adverse effects, especially if dosages are too high, or titrated too quickly (see below).


(1) Severe Intractable Deafferentation Pain Plus Phantom Limb Pain –

A 43-year old male patient suffered (quoting) ‘refractory, severe deafferentation pain’ and phantom limb pain for 23 years, following brachial plexus avulsion and consequent amputation.

Following  administration of SNX-111 (Ziconotide) via continuous intrathecal infusion via a cervical catheter, this patient had complete pain relief as well as (quoting) ‘elimination of hyperesthesia and allodynia‘.

Complete pain relief was still provided to this patient even after dosages were reduced to eliminate side effects.  Thus, SNX-111 (Ziconotide) may offer potent pain relief for both malignant and nonmalignant pain conditions (Brose et al, 1997).

(2) Three (3) Nerve Pain Patients and Ziconotide Infusion –

The 1st patient, with chronic complex regional pain syndrome (CRPS) in the leg, received a single Ziconotide infusion treatment.  This resulted in temporary and complete pain relief.  (There were adverse effects, however.)

The 2nd patient (with painful lumbar radiculitis) received complete (albeit temporary) pain relief following a test dose of Ziconotide infusion.  (There were also side effects.)

The 3rd patient, with persistent bilateral leg and foot nerve pain due to AIDS and related drug therapy, obtained significant pain relief following long-term continuous intrathecal infusion (Wermeling et al, 2006).

(3) Ziconotide in a 16-year-old Male With CRPS in Both Legs –

A 16-year-old boy with CRPS in both legs was given Ziconotide for 3 years.  Pain was reduced at 6 weeks, and a normal gait was achieved at 7 months.  The patient reported NIL pain after 3 years of Ziconotide therapy.  Side effects included urinary retention and depression (Webster, 2005).

(4) Ziconotide in a 17-year-old Female With Chronic CRPS in Right Lower Leg (Initiated by an Ankle Sprain at 13) –

A 17-year-old girl, who was wheelchair-bound due to chronic CRPS in her right lower leg, was given Ziconotide (and other medications) via intrathecal catheter.  As dosages were increased, the swelling in her leg and foot decreased.  At greater dosages, pain levels further decreased and the ‘desquamating skin’ receded toward her right foot.  At times, the edema disappeared completely.

As dosages were further increased, most of her skin scales had disappeared and her foot appeared pink.  Foot movement was regained, as was her quality of sleep that now included a bed cover.  By now, she had also progressed from a wheelchair to crutches.

Further months of Ziconotide therapy brought her VAS Pain Score down to 4 (from 8, pre-Ziconotide).  By now, ambulation and function was greatly improved, with little or no allodynia nor hyperalgesia.

Significant side effects were not observed, and this was attributed to a slow titration of Ziconotide (Stanton-Hicks et al; 2006). 

(5) Ziconotide for 7 CRPS Patients –

Five (5) of 7 CRPS patients had (quoting) ‘substantial improvement in pain, edema, skin abnormalities, and/or mobility with ziconotide therapy’.

In fact, 2 patients had complete pain relief and as such, discontinued Ziconotide treatment altogether.  

A 3rd patient had significantly reduced edema as well as decreased skin trophic changes, following Ziconotide infusion.

Adverse events (including depression, anxiety, hallucinations, and urinary retention) were managed via dose reductions/discontinuation, or otherwise (Kapural et al, 2009).


Several drawbacks and possible adverse effects must be noted including:

Ziconotide requires intrathecal administration.

NB  A properly performed trial of ziconotide infusion should always be done first before consideration is made whether to surgically implant an intrathecal device on a permanent basis, or not.  This trial phase is absolutely necessary to ascertain whether a patient will obtain pain relief from ziconotide in the first place (Knight et al, 2007);


– There is a risk of one or more adverse effects including dizziness, nausea, ataxia, abnormal gait, headache, abnormal sensations, nystagmus (involuntary eye movement), and/or confusion.

To minimise adverse effects while also maximising pain relief, initial dosages should be low, titrated slowly, and gradually increased as necessary.  It may a month (or more) to achieve a fine balance between minimal adverse effects and maximal pain relief (Webster, 2005).

Wishing all pain patients hope, inspiration, and less pain.

Sabina Walker



(1) Brose et al; Use of intrathecal SNX-111, a novel, N-type, voltage-sensitive, calcium channel blocker, in the management of intractable brachial plexus avulsion pain; Clin J Pain (Sep 1997);13(3):256-9.

(2) Wermeling et alZiconotide Infusion for Severe Chronic Pain: Case Series of Patients With Neuropathic Pain; Pharmacotherapy (Mar 2006); 26(3):395-402.

(3) Webster; Ziconotide in Complex Regional Pain Syndrome (2005)

(4) Stanton-Hicks et al;  An Effective Treatment of Severe Complex Regional Pain Syndrome Type 1 in a Child Using High Doses of Intrathecal ZiconotideJ Pain Symp Man (Dec 2006); 32(6):509-11.


(5) Kapural et al; Intrathecal ziconotide for complex regional pain syndrome: seven case reports; Pain Pract (Jul-Aug 2009); 9(4):296-303.

doi: 10.1111/j.1533-2500.2009.00289.x.

(6) Smith, Deer; Safety and efficacy of intrathecal ziconotide in the management of severe chronic pain; Therapeutics and Clinical Risk Management (Jun 2009); 5(3):521–534.

(7) Caraway et al; Intrathecal Therapy Trials with Ziconotide – A Trialing Protocol Before Initiation of Long-Term Ziconotide Intrathecal Therapy is Presented.


(8) Knight et al; Implantable Intrathecal Pumps for Chronic Pain: Highlights and Updates; Croat Med J (Feb 2007); 48(1):22-34.

(9) Miljanich; Ziconotide: Neuronal calcium channel blocker for treating severe chronic pain. Curr Med Chem (2004); 11:3029–3040.

doi: 10.2174/0929867043363884.

(10) Bowersox, Luther; Pharmacotherapeutic potential of omega-conotoxin MVIIA (SNX-111), an N-type neuronal calcium channel blocker found in the venom of Conus magus. Toxicon (Nov 1998); 36(11), 1651–1658.

(11) Rauck et al; Intrathecal Ziconotide for Neuropathic Pain: A Review; Pain Practice (2009); 9:327–337.



(12) Holmes, David; Conotoxins: how a deadly snail could help ease pain; The Lancet Neurology (Sept 2014); 13(9):867-868.


(13) Blog post by another blogger, ‘Baldscientist’

Magnificent Conotoxins – Expanded (27 July 2014)

The blog post by ‘Baldscientist’ includes these References: 

(13A) Brady, Baell, Norton; Strategies for the development of conotoxins as new therapeutic leads; Mar Drugs (Jul 2013); 11(7): 2293–2313.

doi: 10.3390/md11072293

(13B) Essack, Bajic, Archer; Conotoxins that confer therapeutic possibilities. Mar Drugs (2012); 10(6):1244-65.


Adverse Changes in the Brain Caused by Chronic Pain – Is this Reversible If Pain is Eliminated?

Dear Pain Matters blog readers,

It is now known that chronic pain (eg nerve pain) changes the brain.  This is true regardless whether the pain mechanisms are peripherally and/or centrally mediated.

Thus, regardless whether the pain mechanisms reside in the periphery (e.g. in a limb) and/or centrally (in the spinal cord/brain), the brain undergoes significant, adverse changes as a result of severe and persistent pain.  This is called pain-induced cortical reorganization.

The good news is that IF this nerve pain can be blocked, via Nerve Block, pain medicine, surgery, and/or another effective treatment, the brain can change back to normal.

Several studies show this including an important study by Birbaumer et al (1997) involving 6 Phantom Limb Pain patients.

Not only was Birbaumer’s team able to show that:

(1) severe, unrelieved nerve pain (Phantom Limb Pain) causes pain-induced changes in the brain,

(2) but they also showed that these brain changes were reversible,

but only in those patients who ‘experienced a virtual elimination of current phantom pain attributable to anesthesia (quoting from Abstract).   

In other words, the successful, pain-relieving effects of the Nerve Block (Regional Anaesthesia via Brachial Plexus Blockade) was simultaneously reflected by (quoting from Abstract)a very rapid elimination of cortical reorganization‘ in the brain in 3/6 patients.

The most impressive results were observed in a 56 year old patient with severe Phantom Limb Pain who lost his upper limb 28 years earlier.  This man (‘Subject Pr3‘) underwent both:

(1) reversal of pain-induced cortical reorganization; and

(2) complete elimination of Phantom Limb Pain

within only 20 minutes after complete anaesthesia in his stump and shoulder!

NB  It is likely that the pain mechanisms were peripherally mediated in the 3 patients who had pain relief from the Nerve Block.

In summary, the Nerve Block was effective for 3/6 patients with Phantom Limb Pain.  Thus, pain-induced brain changes were rapidly reversed as a direct consequence of the pain-relieving effects of the Nerve Block in these 3/6 patients.  However, this did not happen in the latter 3/6 who did not obtain relief from the Nerve Block.

Thus, the brain appears to change ‘for the worse’ to reflect persistent pain.  On the other hand, the brain is also able to change back to normal if/when persistent pain is finally successfully blocked.


Here is another patient with Phantom Limb Pain named ‘Trevor’:

While Trevor suffered from severe Phantom Limb Pain prior to his Nerve Block, his residual pain is now managed, post-Nerve Block.  Quoting (go to 27:43 in the video link):

“….At that moment, it was instant pain relief for me.”

While this video does not show images of Trevor’s brain, I would bet 2 cents that Trevor’s brain also changed, both ‘before’ and ‘after’ his Nerve Block.


Here’s to less chronic pain in the world,

Sabina Walker


(1) Birbaumer et al; Effects of regional anesthesia on phantom limb pain are mirrored in changes in cortical reorganization; J. Neurosci (1997); 17(14), 5503-5508.

CRPS and Phantom Limb Pain Treated with Memantine or Memantine/Morphine

Dear Pain Matters blog readers,


Three (3) German studies (by the same team) showed promising results following:

– Memantine; or

– Memantine/Morphine Combination Therapy

in CRPS patients.

(1) 1st Study –

In the 1st study, pain decreased in 3 CRPS patients (CRPS duration = 1 to 7 months) following oral Memantine treatment for 8 weeks.  Specifically, there was NIL ‘resting pain’ at the 6-month follow-up (Sinis et al, 2006).

(2) 2nd Study –

In 6 CRPS patients, the duration of CRPS ranged from 4 to 23 months before Memantine Treatment.

Pain decreased significantly, and ‘continuous pain’ disappeared in all 6 CRPS patients after 8-week Memantine Treatment (as at 6-month follow-up).   Motor function also improved, together with Autonomic Nervous System changes, in all 6 patients (Sinis et al, 2007).

(3) 3rd Study –

This study involved 20 CRPS patients, as follows:

– 10 were given ‘Memantine/Morphine Combination Therapy’; and

– 10 were given ‘Placebo + Morphine’.

Duration of CRPS ranged from 6 to 36 months.

In all 10 CRPS patients, ‘pain at rest’ and ‘pain during movement’ decreased significantly following Memantine/Morphine Combination Treatment for 8 weeks. 

Interestingly, the 10 patients who were not given Memantine (the ‘Placebo + Morphine’ group) did not benefit as much.

Only the 10 patients given Memantine/Morphine Combination Treatment for 8 weeks had significant pain reduction and reduced disability.  

… and guess what else happened (that is very interesting)??

Memantine/Morphine Combination Treatment also resulted in significantly reduced activity in certain brain regions (Primary Somatosensory Cortex – contralateral side (S1) and Anterior Cingulate Cortex) when the CRPS-hand was moved!

Thus, Memantine/Morphine Combination Treatment resulted in decreased pain.  Furthermore, this decreased pain was mirrored via reduced activity in certain brain regions (S1, S2) (Gustin et al, 2010).  


Two (2) patients had severe Phantom Limb Pain as a consequence of severe lower leg injuries.  When oral Memantine treatment was given, these 2 patients had significant reduction in Phantom Limb Pain (Hackworth et al, 2008).  More studies are needed.


In summary, treatment involving Memantine or Memantine/Morphine warrants more attention given its impressive results in:

– (a total of) 19 CRPS patients; and

– 2 patients with Phantom Limb Pain

who received either Memantine alone or Memantine/Morphine.  

Sabina Walker



Memantine/Morphine Combination Therapy may alleviate painful symptoms of CRPS by reducing tumor necrosis factor-α (TNF) and other inflammatory mediators.  An animal study reported that administration of Memantine Hydrochloride decreases TNF expression in rats.  Studies are warranted to determine whether Memantine decreases local TNF in pain patients including CRPS patients.  (Memantine is widely known for its antagonistic effects on the NMDA receptor.)

(Please refer to Review Paper by Sabina Walker and Prof. Peter Drummond for further details.  In particular, please refer to pages 1796 – 1797, plus 4 Memantine-related References on pages 1805-1806, plus papers below.)



(1) Gustin SM, Schwarz A, Birbaumer N, et al. NMDA-receptor antagonist and morphine decrease CRPS-pain and cerebral pain representation. Pain 2010;151:69–76.

(2) Sinis N, Birbaumer N, Gustin S, et al. Memantine treatment of complex regional pain syndrome: A preliminary report of six cases. Clin J Pain 2007;23: 237–43.

(3) Sinis N, Birbaumer N, Schwarz A, et al. Memantine und komplexes regionales Schmerzsyndrom (CRPS): Behandlungseffekte und kortikale Reorganisation (Memantine and complex regional pain syndrome (CRPS): Effects of treatment and cortical reorganisation). Handchir Mikrochir Plast Chir 2006;38:164–71. (in German).

(4) Sabina Walker, Peter D. Drummond; Implications of a Local Overproduction of Tumor Necrosis Factor-α in Complex Regional Pain Syndrome [Review Paper, 24 pages]; Pain Medicine (Dec 2011), 12 (12), 1784–1807.

In particular, please refer to pages 1796 – 1797, plus 4 Memantine-related References on pages 1805-1806.

(5) Park et al; Antinociceptive Effect of Memantine and Morphine on Vincristine-induced Peripheral Neuropathy in Rats; Korean Journal of Pain (Sept 2010); 23(3):179-185.

doi: 10.3344/kjp.2010.23.3.179.


(6) Hackworth et alProfound pain reduction after induction of memantine treatment in two patients with severe phantom limb pain; Anesth Analg (2008); 107:1377–1379.

Long-Lasting Reduction of Phantom Limb Pain Following Pharmaceutical Blockade of the Brachial Plexus

Dear Pain Matters blog readers,

More hope for Phantom Limb Pain sufferers…

Phantom Limb Pain was reduced for a long time (in fact, 6 months) in one patient following pharmaceutical blockade of the brachial plexus.  

Prior to this single temporary blockade, this patient had suffered years of Phantom Limb Pain and cramping of his immovable phantom hand.

During a diagnostic axillary blockade of the brachial plexus, the patient experienced a reduction of Phantom Limb Pain for the first time in years.  The muscles in his phantom hand became relaxed and the ‘cramping’ in his phantom hand was also 100% eliminated.

The reduction in Phantom Limb Pain was accompanied by blockade-induced cortical reorganisation in the primary somatosensory cortex (i.e. re-reorganisation).

In summary, the good news:

The beneficial effects of a sole blockade of the brachial plexus were long-lasting (extending out to 6 months after a single temporary blockade) in this one patient.

Given the long-lasting therapeutic effects of the Brachial Plexus Blockade in this patient, it is likely that his Phantom Limb Pain was (at least in part) caused by peripheral mechanism(s).

The mechanisms underlying Phantom Limb Pain may vary from one patient to the next, and may either be peripherally– and/or centrally-mediated.  Once (pain-inducing) mechanisms are identified, pain treatment options may be tailored to each patient, hopefully leading to reduced pain levels as well as improved function and well-being.

(Possible mechanisms underlying chronic pain will be discussed in future blog posts.)


Another patient, ‘Derek’ (see below Youtube that shows 4 pain patients) had severe Phantom Limb Pain before he was offered a Nerve Block.  Derek’s Phantom Limb Pain had resulted due to amputation above his left knee following a blast while deployed in Iraq.  

The pain-reducing effects of a Nerve Block were amazing, and gave Derek a new lease on a life with significantly reduced Phantom Limb Pain and increased mobility (that even included long-distance running via a specially-designed prosthesis).  

Regarding the successful pain-relieving effects of his Nerve Block, Derek states (quoting; go to 27:43 in the Youtube, below):

“….At that moment, it was instant pain relief for me.”

Thus, Derek’s Nerve Block offered instant and complete pain relief.  This suggests that the mechanisms underlying Derek’s nerve pain including Phantom Limb Pain were completely peripherally-mediated (more on pain mechanisms later). 

Wishing you ALL a great, pain-free day,

Sabina Walker

References (NB This is not a complete list of References):

(1) Preißler et al; Brachial Plexus Block in Phantom Limb Pain: A Case Report; Pain Medicine (Nov 2011); Vol 12 (11); 1649–1654;

DOI: 10.1111/j.1526-4637.2011.01247.x

Possible Reduction of Phantom Limb Pain via Osseointegrated (Bone-Anchored) Prosthetic Limb

Dear Pain Matters blog readers,

A recent article in Science Translational Medicine journal by Max Ortiz-Catalan et al (8 October 2014) offers hope that Phantom Limb Pain may be reduced in some patients with Phantom Limb Pain.  Specifically, Phantom Limb Pain was reduced by 40% in a patient following implantation of an osseointegrated (i.e. bone-anchored) prosthetic arm.  (His arm was amputated above the elbow.)

A small fixture was internally anchored into the bone at the stump, while an external anchor was added to connect the prosthesis to the stump.  Additionally, seven (7) electrodes were implanted into the stump’s connective tissue including muscles and peripheral nerves (to transmit electrical information between the brain and skeletal muscles for prosthetic arm movement).

Not only did this osseointegrated prosthetic arm (with an implanted neuromuscular interface; ie 7 electrodes) facilitate a greater range of motion than a traditional prosthetic, but these 7 implanted electrodes also enabled improved electrical communication between the brain and muscles.  This leads to more control of the osseointegrated prosthetic arm including improved manipulation of very small items.  (Currently, electrodes are externally placed on top of the skin in some patients.)

Electrical pulses were sent to the stump’s muscles and peripheral nerves via the 7 implanted electrodes, enabling simulation of sensation in the amputated arm that was perceived as a ‘pulsing’ or ‘tingling’ sensation sensation by the patient (depending on pulse intensity).

Now here is the interesting part regarding the patient’s Phantom Limb Pain: The osseointegrated prosthetic arm also resulted in a 40% reduction in the patients’ Phantom Limb Pain.  Thus, a bone-anchored prosthetic arm may offer a novel treatment option that may significantly reduce Phantom Limb Pain in some patients with intractable Phantom Limb Pain.

For more on Bionic Limb expert, Max Ortiz-Catalan, please refer to:

Further references (NB This is not a complete list of References):

(1) Ortiz-Catalan M, Hakansson B, Branemark R; An Osseointegrated Human-Machine Gateway for Long-Term Sensory Feedback and Motor Control of Artificial Limbs; Science Translational Medicine, 2014; 6 (257): 257re6 DOI: 10.1126/scitranslmed.3008933

(2) Chalmers University of Technology. Mind-Controlled Prosthetic Arms that Work in Daily Life are Now a Reality; ScienceDaily, 8 October 2014

(3) Hiscott R; One Step Closer to Bionic Limbs: Researchers Simulate Sensation in Prosthetic Arms; 8 October 2014