Stump Neuroma Research Articles

Ultrasound in interventional pain management

Ultrasound (US) is an increasingly used imaging technique in interventional pain management. It allows the identification of soft tissues, vessels and nerves, without exposing patients and personnel to radiation. Imaging can be performed continuously and the fluid injected is visualized in a real time fashion. Possible applications are nerve blocks of the cervical and lumbar zygapophysial joints, stellate ganglion block, intercostal nerve blocks, blocks of painful stump neuromas, caudal epidural injections and injections of trigger/tender points. Due to direct nerve visualization, US has a potential application for destructive procedures, such as cryoanalgesia, radiofrequency lesions or chemical neurolysis. Limitations are the poor resolution of narrow-gauge needles, the lost of resolution with increasing working depth and possible interference of echoes from overlying structures with the image of the target area. US opens new perspectives in interventional pain management. However, there is a need for clinical trials investigating efficacy and safety of US-guided pain procedures. Until these studies are made, US can not replace fluoroscopy or computed tomography in routine clinical practice and remainS domain of well-trained and experienced physicians. The limited evidence supporting the clinical utility of nerve blocks remains a problem, irrespective of the imaging technique employed.

Practical Experience with Sonographically Guided Phenol Instillation of Stump Neuroma: Predictors of Effects, Success, and Outcome

Phantom limb pain and stump pain frequently occur after limb amputation, and stump neuromas play an important role in generation of the pain. The purpose of this study was to evaluate the effects of a previously described optimized procedure for sclerosis of painful stump neuromas under real-time high-resolution sonographic guidance. In this prospective study, neurosclerosis was performed on 82 patients by means of high-resolution sonographically guided injection of up to 0.8 mL of 80% phenol solution according to a standardized protocol. During treatment all patients had marked improvement in terms of reduction of pain measured with a visual analog scale. Twelve (15%) of the subjects were pain free after one to three treatments, nine of the 12 achieving relief with the initial instillation. At 6-month follow-up evaluation, 52 patients assessed their present pain quantity with a simplified three-step score. Twenty (38%) of the 52 patients reported almost unnoticeable pain, and 33 (64%) reported pain equal to the minimum reached during therapy. In 18 (35%) of the 52 patients, the incidence of painful periods had markedly decreased. The neurosclerosis procedure had a low complication rate (5% rate of minor complications, 1.3% rate of major complications). The high-resolution sonographically guided neurosclerosis procedure had a significantly better outcome than other documented treatments. Sonographically guided neurosclerosis should be included in the management of chronic phantom limb and stump pain.

Bridging Critical Nerve Defects through an Acellular Homograft Seeded with Autologous Schwann Cells Obtained from a Regeneration Neuroma of the Proximal Stump

Over the last decade, several models have investigated the usefulness of different biologic and/or synthetic matrices as alternatives to conventional nerve grafts. Still, axonal regeneration did not occur over longer (> 3 cm) distances. One problem may be that a growth-promoting environment not only includes physical cues but also a rich spectrum of different growth factors only provided by reactive Schwann cells. In the current study, we investigated whether a hybrid graft consisting of first-generation autologous Schwann cells seeded onto an acellular auto- or homograft can aid regeneration across a critical nerve defect in a rat model. In this paradigm, Schwann cells were not expanded in vitro but harvested from the proximal stump neuroma at the time of reconstruction and seeded into either an acellular homo- or autograft. Regeneration was then quantitated with functional muscle testing, regular histology, histomorphometry, and retrograde tracing techniques 12 weeks after reconstruction. Results showed successful regeneration over the entire distance regardless of whether Schwann cells were transplanted onto auto- or homologous acellular matrix. Schwann cells did populate both grafts; however, only sensory axons persisted through the entire distance. The functional outcome was dismal with no motor and poor sensory recovery. Control group C with homologous matrix only without Schwann cells showed no signs of directed axonal regeneration. Control group D with autologous reverse graft showed excellent recovery, as was expected. The present experiment sought to create a hybrid graft where the proximal stump neuroma is used as a biological resource for autologous Schwann cells that are seeded unto an acellular matrix, thus providing both physical and chemical support to regenerating axons. The results are encouraging in that successful regeneration was observed over the entire distance; however, only sensory axons had enough regenerative potential to also make end-organ contact. For motor axons, further refinements in conduit preparation have to be done.

Brachial Plexus Neuroma Mimicking Local Recurrence of Malignant Mesenchymal Tumor After Forequarter Amputation

A stump neuroma is an attempt for the repair of a nerve following amputation. This article presents a case of a 60-year-old woman who was suspected of having a local recurrence on the chest wall following amputation of the left arm for a malignant mesenchymal tumor. The tumor did not show any invasion to adjacent structures thereby any necessity for chest wall resection and reconstruction. The patient underwent local excision of the tumor with reamputation of the branches of the lower brachial plexus, subclavian artery, and proximal one third of the clavicle. The tumor was eventually diagnosed as a brachial plexus neuroma. Although rare, cases that require left pneumonectomy with a transthoracic forequarter amputation including brachial plexus resection have been reported. Transection of the brachial plexus also may be needed during resection of a superior sulcus tumor. These cases often undergo an aggressive chest wall resection that includes the subclavian artery and vein in addition to the brachial plexus, particularly in tumors involving the lower truncus. Therefore, when recurrent chest wall tumor is suspected in such cases, stump neuroma resulting from transection of the brachial plexus should be included in the differential diagnosis.

Role of Nd:YAG laser for prevention of neuroma formation: an in vivo experimental study

Nerve transection is commonly followed by the development of neuroma at the proximal stump. It can be very painful especially at exposed sites. It may arise spontaneously or after mechanical irritation. Neuroma and its high recurrence rate might be resisting problems to treat. Various treatment modalities for neuroma and its recurrence have been proposed, but none has provided satisfactory results. The present study was conducted to evaluate the neodymium:yttrium aluminum garnet (Nd:YAG) laser (1,064 nm) nerve transection technique for prevention of neuroma formation. There were 48 facial nerves out of 24 Rex rabbits divided into two equal groups. The 24 left-sided facial nerves at group A were subjected to Nd:YAG laser for nerve transection, while the 24 right-sided facial nerves at group B were subjected to scalpel nerve transection. The results were grossly and histopathologically evaluated. Grossly, laser-transected nerves showed an infrequent incidence of neuroma formation. Histopathologically, laser-transected nerves showed photothermal degenerative changes of the axons and myelin sheaths with intact perineurium and endoneurium. No Schwann cell hyperactivity could also be elicited among laser-transected nerves. Nd:YAG laser was found to be an effective tool that could be applied, whenever it is possible, for division of major nerves to prevent the formation of the subsequent stump neuroma. Moreover, this technique should be considered during treatment of well-established neuroma to prevent the challenging reported high incidence of recurrence.

Ultrasound-guided blocks for the treatment of chronic pain

Ultrasound (US) is an emerging imaging technique in interventional pain management. The main advantages are the identification of soft tissues, vessels, and nerves, without exposing patients and personnel to radiation, the possibility to perform continuous imaging, and the visualization of the fluid injected in a real-time fashion. Possible applications are nerve blocks of the cervical and lumbar zygapophysial joints, stellate ganglion block, intercostal nerve blocks, occipital nerve blocks, blocks of the inguinal nerves, peripheral nerve blocks of the extremities, blocks of painful stump neuromas, caudal epidural injections, and injections of tender points. US may also be used for destructive procedures, such as cryoanalgesia, radiofrequency lesions, or chemical neurolysis. The increasing published data available suggest that US has a potential usefulness in interventional pain management, but also limitations. There is still a need for clinical trials investigating efficacy and safety of US-guided pain procedures. Until these studies are made, fluoroscopy or computed tomography remain the gold standard for most interventional pain procedures.

Ultrasound-guided Interdigital Neuroma Injections: Short-term Clinical Outcomes after a Single Percutaneous Injection—Preliminary Results

To describe the procedure of ultrasound-guided Morton's neuroma and recurrent stump neuroma injections and early clinical outcomes after a single injection. Retrospective review of 44 percutaneous ultrasound-guided neuroma injections in 24 patients who had completed clinical outcomes questionnaires. A 10-point pain scale [scale of 1 (no pain) to 10 (severe pain)] in a 7-day pain log format was distributed to patients at the time percutaneous neuroma injection was performed. Neuromas were clearly visualized with sonography as hypoechoic nodules and were distinguishable from other causes of forefoot pain, such as metatarsophalangeal joint synovitis and intermetatarsal bursae. The sizes of the neuromas injected ranged between 4 and 19 mm. Postinjection, all neuromas displayed increased echogenicity and/or the appearance of fluid surrounding it, confirming localization of the therapeutic mixture. We arbitrarily subdivided the pain ratings into symptomatic (greater than 4) and asymptomatic (less than or equal to 4) for statistical analysis. Average pain level pre injection was 5.2 and average pain level was 3.7 at 7 days post single injection, with 62% of the initially symptomatic patients asymptomatic on day 7 (p < 0.000001). Overall, 76% of the total number of neuromas injected once were asymptomatic on day 7. Ultrasound can be used to accurately target Morton's neuromas and, therefore, appropriately direct therapeutic interventions, with good short-term clinical results.

Coverage of Painful Peripheral Nerve Neuromas with Vascularized Soft Tissue: Method and Results

Our goals are to describe a method of treating painful peripheral nerve neuromas by means of vascularized tissue coverage, report the results in seven patients, and discuss the indications for this treatment modality. An analysis of pain, functionality of the affected body part, professional activities of the patients, and medications before and after surgery is presented. Seven male patients (mean age, 45.1 yr) with posttraumatic nerve injuries, who had developed painful stump neuromas or neuromas-in-continuity, and who had unsuccessfully undergone several treatment procedures, were selected for the surgery described here. The operation included resection of the stump neuroma (four patients) or neurolysis of the neuroma-in-continuity (three patients) and coverage of the nerve with a vascularized fascial, fasciocutaneous, or perforator flap (three pedicled regional flaps and four free flaps). A modified quadruple visual analog scale was used to quantify pain before and after surgical treatment. The mean follow-up was 16.6 months. The mean values of the quadruple visual analog scale (pain now/typically/at its best/at its worst) before surgery were 6.5/6.5/4.7/7.9. These values changed to 0.3/0.4/0/0.9 at a mean follow-up of 16.6 months after surgery. Five patients returned to their original profession, one receives a pension, and one began a less demanding job after undergoing surgery. Six of the seven patients received opioids before surgery (one had a spinal cord stimulator). After surgery, all patients stopped taking regular pain killers and the spinal cord stimulator was deactivated in one; two patients still take nonsteroidal anti-inflammatory drugs occasionally, but not on a regular basis. Vascularized soft tissue coverage of painful peripheral nerve neuromas seems to be an effective and attractive, but also complex, method of treatment. This option may be considered and reserved for patients who have already undergone several pain treatment modalities without success.

Ultrasound in interventional pain management

Ultrasound (US) is a promising imaging technique in interventional pain management. It allows the identification of soft tissues, vessels, and nerves, without exposing patients and personnel to radiation. Imaging can be performed continuously and the fluid injected is visualized in a real-time fashion. Possible applications are nerve blocks of the cervical and lumbar zygapophysial joints, stellate ganglion block, intercostal nerve blocks, peripheral nerve blocks of the extremities, blocks of painful stump neuromas, caudal epidural injections, and injections of tender points. US can be used not only for local anesthetic blocks, but has a potential application for destructive procedures, such as cryoanalgesia, radiofrequency lesions, or chemical neurolysis. The very limited published data available and the clinical experience by the authors suggest that US has a potential usefulness in interventional pain management, but also has limitations. There is a need for clinical trials investigating efficacy and safety of US-guided pain procedures. Until these studies are made, US cannot replace fluoroscopy or computed tomography in routine clinical practice. Rather, only physicians who have been trained appropriately and practice under supervision of an experienced sonographer should use it, until familiarity with the method is gained.

Sonographically guided phenol injection in painful stump neuroma.

Sonographically guided phenol injection in painful stump neuroma.

IRM et névromes des moignons dˈamputation des membres inférieurs

OBJECTIVE: To describe RMI aspects of leg stump neuroma and to evaluate RMI scan interest for neuroma diagnosis and management. POPULATION AND METHOD: During a 2 years period, 224 amputated patients consulting for pain or prostetics problems were studied. In 10 cases, a characteristic pain leads to neurona diagnosis. This is described as a sensation of ascending or descending electric shock induced by the stimulation of an identified point with a reproducible topography. In all these cases, RMI scans were performed. In thirty two other cases, a RMI scan was performed to confirm a pathology (bursitis, bone abnormality) or in order to establish an etiologic diagnosis. Twelve neuromas were diagnosed. RESULTS: RMI scan showed a neuroma in the ten cases with a clinical suspicion and two asymptomatic neuromas were diagnosed out of the 32 patients without clinical suspicion. Medium delay between amputation and neuroma diagnosis is 11,6 year. In six cases, staking was modified and in six other cases, surgery was necessary. In aIl cases, clinical manifestations disappeared. Vanous RMI aspects ofneuromas are described and illustrated. Neuroma is observed on the extremity of a nerve that have a wavy aspect on its top. The neuroma is an oblong structure, with clear limits. There is an hyposignal with Ti sequence and variable signal with T2 and after gadolinium injection. DISCUSSION: RMI scan is a good way to diagnose amputee neuroma. It makes it possible to demonstrate the pathological character of the neuroma. It has to be performed when a neuroma is suspected. It enables to confirm the diagnosis and establish the exact topography and anatomic connection. Mechanical strains role as a factor of discovering the neuroma is discussed because of the concomitant evolution of associated lesions (bursitis, bone edema).Surgical repair takes place after correcting abnormal mechanical strains.

Peripheral nerve lengthening by controlled isolated distraction: a new animal model

We have developed a simple and effective animal model to study the distraction neurogenesis utilizing the sciatic nerve-lengthening technique in rats. The model allows macroscopic, physiological, and histological evaluation of the distraction site. Fourteen adult Harlan Sprague Dawley rats (300–350 g) were used in this study. A 10 mm segment of the right sciatic nerve of each animal in the nerve-lengthening group was resected. Gradual nerve lengthening was performed by advancing the proximal nerve stump at a rate of 1 mm/day. The proximal stump neuroma was then resected and a direct nerve anastomosis was performed. On the left side a standard autogenous nerve-grafting procedure was performed with a 10 mm segment of sciatic nerve used as an in situ nerve graft. Three months after the second surgery, the sciatic nerves were exposed and investigated by gross observation and EMG followed by histological processing and tissue analysis. Neomicrovascularization was observed surrounding the sciatic nerve anastomosis in all five specimens of the nerve-lengthening group as compared to the more white-colored scar tissue that was observed in the nerve-grafting group. The EMG results were similar for both groups. Histological studies of the lengthened nerves showed axon morphology equivalent to the grafted nerves. This study demonstrated a clear evidence of the successful nerve regeneration within a segmental nerve gap by nerve lengthening.

Topical lidocaine patch relieves a variety of neuropathic pain conditions: an open‐label study. (Department of Pain Medicine and Palliative Care, Beth Lsrael Medical Center, New York, NY) Clin J Pain 2000;16:205–208.

Our goal was to perform a pilot, open‐label, prospective study to access the effectiveness and tolerability of a topical lidocaine patch (Lidoderm) for the treatment of peripheral neuropathic pain conditions other than postherpetic neuralgia. Sixteen patients with refractory peripheral neruopathic pain conditions who had reported intolerable side effects or inadequate pain relief with antidepressant, anticonvulsant, antiarrhythmic, and opioid medications participated in this study. Diagnoses included postthoracotomy pain, stump neuroma pain, intercostal neuralgia, diabetic polyneuropathy, meralgia paresthetica, complex regional pain syndrome, radiculopathy, and postmastectomy pain. A 6‐item Pain Relief Scale was used. Moderate or better pain relief was reported by 13 of the 16 participants (81%). One patient stopped treatment after 4 days due to lack of relief. The remaining 15 patients had a mean duration of patch use of 6.2 weeks with continued relief. Only 1 patient reported a side effect, a mild skin irritation. Conclude the Lidoderm patch provides clinically meaningful pain relief in most of these refractory neuropathic pain patients without side effects. Controlled trials need to be performed to confirm these preliminary findings.Comment by Tat‐Leang Lee, M.D. This is an interesting study that highlighted a simple, efficacious method for the treatment of resistant neuropathic pain. As this was a pilot study using an open‐label method, and treating a heterogenous group of neuropathic pain conditions, caution should be adopted in the interpretation of the results. What remains unanswered is the reason for the success of the lidocaine patch, particularly when previous studies have documented the failure of EMLA in the treatment of neuropathic pain. Indeed, several patients who participated in this study had used EMLA unsuccessfully before, although no details on its administration was reported. Both the lidocaine patch and EMLA contain 5% lidocaine, which presumably would result in greater penetration by the EMLA cream. Therefore, a placebo‐controlled randomized trial is needed to confirm the findings of this pilot study. Nevertheless, this is a promising treatment that is convenient, lacks systemic effect, easily added‐on to existing treatment, and with only minor side effects, that is worth considering for our patients.

Psychophysical correlates of phantom limb experience.

Phantom limb phenomena were correlated with psychophysiological measures of peripheral sympathetic nervous system activity measured at the amputation stump and contralateral limb. Amputees were assigned to one of three groups depending on whether they reported phantom limb pain, non-painful phantom limb sensations, or no phantom limb at all. Skin conductance and skin temperature were recorded continuously during two 30 minute sessions while subjects continuously monitored and rated the intensity of any phantom limb sensation or pain they experienced. The results from both sessions showed that mean skin temperature was significantly lower at the stump than the contralateral limb in the groups with phantom limb pain and non-painful phantom limb sensations, but not among subjects with no phantom limb at all. In addition, stump skin conductance responses correlated significantly with the intensity of non-painful phantom limb paresthesiae but not other qualities of sensation or pain. Between-limb measures of pressure sensitivity were not significantly different in any group. The results suggest that the presence of a phantom limb, whether painful or painless, is related to the sympathetic-efferent outflow of cutaneous vasoconstrictor fibres in the stump and stump neuromas. The hypothesis of a sympathetic-efferent somatic-afferent mechanism involving both sudomotor and vasoconstrictor fibres is proposed to explain the relationship between stump skin conductance responses and non-painful phantom limb paresthesiae. It is suggested that increases in the intensity of phantom limb paresthesiae follow bursts of sympathetic activity due to neurotransmitter release onto apposing sprouts of large diameter primary afferents located in stump neuromas, and decreases correspond to periods of relative sympathetic inactivity. The results of the study agree with recent suggestions that phantom limb pain is not a unitary syndrome, but a symptom class with each class subserved by different aetiological mechanisms.

Changes in myelinated and unmyelinated axon numbers in the proximal parts of rat sural nerves after two types of injury

Counts of myelinated and unmyelinated axon profiles have been made from normal, uninjured rat sural nerves and from nerves injured 6 months earlier in one of two ways. In one group of rats the nerve was simply cut and left to regenerate, leading to the development of a neuroma in continuity, while in the second group the nerve was cut but then ligated as well to prevent regeneration; this led to stump neuroma formation. After nerve transection and regeneration, with subsequent formation of a neuroma in continuity, there was no change in the number of myelinated axon profiles found 25 mm proximal to the old injury site when compared with control, but there was an 18% reduction (P < 0.05) in the number of unmyelinated axon profiles. Immediately proximal to the injury site the picture was similar, with there still being the same number of myelinated axon profiles as in control material but here the reduction in unmyelinated axon numbers was slightly greater at 24% (P < 0.05). In the proximal part of nerves that had been cut and stump neuroma formation induced there was a large increase (33%) in myelinated axon profiles over and above control values (P < 0.001) but the number of unmyelinated profiles was the same as in controls. Closer to the stump neuroma the number of myelinated axon profiles had increased yet further to be 88% (P < 0.001) above control while the number of unmyelinated ones remained no different from control. Our interpretation of these results is that after nerve transection and regeneration there is no loss of peripheral neurons supporting myelinated axons but some loss of those supporting unmyelinated ones. If a cut nerve is prevented from regenerating and a stump neuroma forms, however, a vigorous sprouting response is triggered in neurons with myelinated axons while those supporting unmyelinated axons are possibly prevented from dying. The reaction of peripheral neurons to injury is such that the number of axons they support varies along the nerve as one goes disto-proximally away from the injury site. Thus discrepancies in results from different laboratories have come about because material for axon counting has been taken from different points along the nerve relative to the injury site and also because the material has been taken from nerves injured in different ways.

MR Imaging of Stump Neuroma

Painful stump neuromas in the postamputation patient are difficult to diagnose and treat. We report a case in which magnetic resonance allowed precise preoperative diagnosis and localization of such a lesion. Magnetic resonance, with its ability for long axis imaging in the extremity, is ideally suited for the workup of stump neuromas.

A new operation for the prevention and treatment of amputation neuromas.

A stump neuroma is caused by the disorganised growth of axon cylinders into proliferating granulation tissue, but this is stopped by an undamaged epineural sleeve. We report experiments in the rat in which the epineural sleeve of the stump of the sciatic nerve was freed from nerve fascicles for about 5 mm and then sealed with a synthetic tissue adhesive. Neuroma formation was largely prevented in comparison with the results of other methods. This new technique has been used to treat 68 painful neuromas in 36 patients. All but three of the patients were cured or improved and none were made worse.

Stump Neuroma Masquerading as Recurrent Malignancy on Chest Roentgenogram

An amputation neuroma is a nerve's attempt at repair following amputation. While many are asymptomatic, some present as a painful mass. We describe a patient who, following a forequarter amputation for sarcoma, developed a stump neuroma that was unusual because it was first discovered on a routine chest roentgenogram.

Postamputation neuromas and other symptomatic stump abnormalities: detection with CT.

One of the potentially troublesome sequelae of limb amputations is the development of stump neuromas at the severed ends of major nerves. The ability to define them and to distinguish them from other causes of stump pain is of considerable clinical significance. Computed tomography was performed on ten lower limb amputees with stump pain. Five patients had neuromas that were manifest as focal or generalized alteration in the caliber, size, or contour of the nerve trunk in the affected stump. The remaining five patients each had an abnormality detected; these abnormalities included heterotopic bone formation, popliteal artery aneurysm, lipoma, scar tissue, and abscess in the contralateral limb.

4. Interactions between fibres in experimental neuromata in rats

Some nerve fibres trapped within stump neuromata show spontaneous activity and this abnormal, ectopic activity may be involved in the aetiology of painful disturbances of sensation that sometimes follow peripheral nerve injury. Here we report that indirect interactions between fibres ending in a stump neuroma can alter the patterns of this spontaneous activity.