The cortical somatotopic map and phantom phenomena in subjects with congenital limb atrophy and traumatic amputees with phantom limb pain

The extent of the cortical somatotopic map and its relationship to phantom phenomena was tested in five subjects with congenital absence of an upper limb, four traumatic amputees with phantom limb pain and five healthy controls. Cortical maps of the first and fifth digit of the intact hand, the lower lip and the first toe (bilaterally) were obtained using neuroelectric source imaging. The subjects with congenital upper limb atrophy showed symmetric positions of the left and right side of the lower lip and the first toe, whereas the traumatic amputees with pain showed a significant shift (about 2.4 cm) of the cortical representation of the lower lip towards the hand region contralateral to the amputation side but no shift for the toe representation. In healthy controls, no significant hemispheric differences between the cortical representation of the digits, lower lip or first toe were found. Phantom phenomena were absent in the congenital but extensive in the traumatic amputees. These data confirm the assumption that congenital absence of a limb does not lead to cortical reorganization or phantom limbs whereas traumatic amputations that are accompanied by phantom limb pain show shifts of the cortical areas adjacent to the amputation zone towards the representation of the deafferented body part.     

Inhibition and axial deviation of limb regeneration in the newt by means of a digit implanted into the amputated limb

This research was designed to follow up the observation of Thornton and Kraemer ('51) that regressed, denervated limbs of Ambystoma larvae will not regenerate upon reinnervation if all digits on the limbs were not completely resorbed. The object of this experiment was to determine whether the presence of an apical structure, protruding past the amputation surface, would affect the regenerative process. Both forearms of adult newts were amputated midway between the elbow and the wrist. One limb served as a normal regeneration control, and in the other limb the third digit from the removed hand was implanted in place of the removed radius, so that the three distal phalangeal segments protruded past the plane of amputation. Blastema formation in the experimental limbs was delayed by several weeks as compared with control limbs. Approximately one third of the experimental limbs did not regenerate. The regenerates that did form were strongly deviated (45-90 degrees) radially from the longitudinal axis of the limb. Experimental analysis showed that the delay in regeneration is due largely to the projecting part of the digit. The radial deviation of the regenerates is not due to the digital implant, but rather to the removal of the radius. Trauma alone does not account for this phenomenon.     

A case report of steroid-responsive progressive encephalomyelitis with rigidity showing muscle stiffness limited to the upper body

A 37-year-old female presented with progressive encephalomyelitis with rigidity for a period of about three months. Spasms began with several minutes of paroxysmal painful muscle stiffness in the left upper limb, followed by pain and muscle spasms in the upper limbs, shoulders, neck and back. The paroxysmal painful spasms were easily evoked by light touches and startling. The patient had contracture in the upper limbs and difficulty in relaxing the muscles. She also developed brain stem signs such as left sixth nerve palsy. The serum antinuclear antibody was positive (1 : 160). The cerebrospinal fluid examination revealed mild pleocytosis and protein elevation. Brainstem MRI, cervical MRI, and electroencephalography were normal. Surface electromyography in the arm and neck muscles showed continuous motor unit discharge elicited by passive movement of the right arm. Diazepam and baclofen were minimally beneficial. After treatment with intravenous injection of high-dose methylprednisolone and sequential oral prednisolone administration, the patient showed substantial improvement. This disorder may be part of a clinical spectrum that has an underlying autoimmune basis.     

Limb swelling in patients who have fibrodysplasia ossificans progressiva

Fibrodysplasia ossificans progressiva is a rare heritable disorder of connective tissue characterized by progressive heterotopic ossification of soft tissues and by congenital malformation of the great toes. Limb swelling has also been noted, yet little is known about this complication of fibrodysplasia ossificans progressiva. To determine the prevalence of limb swelling in this condition, the authors reviewed detailed medical records on 74 patients (25 males, 49 females; age range, 1-49 years) who had a documented history of fibrodysplasia ossificans progressiva. The study population included more than 90% of all patients known to have fibrodysplasia ossificans progressiva in the United States. Acute swelling of the limbs occurred in association with flareups of the condition in nearly all cases. Acute swelling in the upper limbs was focal and nodular in contrast to acute swelling in the lower limbs, which was more diffuse. Acute swelling in the upper limbs occurred in all 74 patients whereas acute swelling in the lower limbs occurred in 47 of the 74 patients (64%). Two of the 74 patients who had acute swelling in the lower limbs (4%) had a documented episode of deep vein thrombophlebitis. Chronic swelling in the upper limbs occurred in 9 of the 74 patients (12%) and was not seen before the age of 12 years. Chronic swelling in the lower limbs occurred in 36 of the 74 patients (49%) and was not seen before the age of 9 years. The intense angiogenesis and edema seen on histopathologic evaluation of preosseous fibrodysplasia ossificans progressiva lesions may play a role in the pathogenesis of the limb swelling. The data show an age related prevalence of limb swelling in fibrodysplasia ossificans progressiva and suggest a model for understanding the complex pathways leading to limb swelling in this disorder.     

A case of early-onset cortical cerebellar atrophy with rhythmic skeletal myoclonus in the left upper limb

A 19-year-old man developed progressive unsteady gait and speech disturbance two years ago. He recently noticed muscle twitches in the left limb. Neurological examination revealed scanning speech, saccadic ocular movement, ataxia of trunk and limbs predominant on the left side. Rhythmic myoclonus was present at rest around the left shoulder and arm, and amplified by raising the left arm. There was no myoclonus in the soft palate. MRI revealed only a cerebellar atrophy. This patient was diagnosed as having cortical cerebellar atrophy with rhythmic skeletal myoclonus (RSM). Tc-99m ECD SPECT showed a decrease in the blood flow of the right thalamus when the myoclonus was enhanced by raising the left upper limb, which suggests that the cerebello-thalamo-cortical system as well as Guillain-McIlaret triangle is involved in the development of RSM.     

Bone mineralization in the affected extremities of children with spastic hemiplegia

To assess the impact of neurologic involvement on bone mineralization, dual-energy X-ray absorptiometry was used to quantitate bone mineral content (BMC), bone mineral density (BMD), fat and lean muscle mass in the limbs of 19 children with spastic hemiplegic cerebral palsy. The BMC in the affected limb was on average 26.5% lower (upper limbs) and 15.6% lower (lower limbs) than in the corresponding uninvolved limb. Lean muscle mass was reduced by 15% and BMD by 6% in the involved limbs and did not differ significantly between upper and lower limbs. The fat content of involved and uninvolved limbs did not differ. Children with poor hand function had greater reductions in BMC (39.3%), BMD (11.3%) and lean muscle mass (22.5%) than did children with better hand function. Thus, bone size and density decrease with increasing neurologic involvement, and weight bearing may slightly lessen the effect.     

Traumatic forearm amputation with avulsions of the ulnar and median nerves from the brachial plexus

A case of a traumatic forearm amputation and associated complete avulsions of the ulnar and median nerves from the brachial plexus due to a crush-traction injury of the distal part of the right forearm is reported. The patient also suffered a traumatic head injury. The injury of the upper limb and the general condition of the patient were so serious that an amputation at the 1/3 middle part of the forearm had to be performed.     

Sex chromatin in hair roots--25 years later: fluorescence in situ hybridization of hair root cells for detection of numerical chromosome aberrations

Primary nerve repair yields better results than secondary reconstruction but is not always possible. We reviewed a series of 2,181 fresh nerve injuries of the upper limb. One nerve only was injured in 41% of the patients; two or more in 59%. One thousand four hundred eighty-two injuries (68%) were located in the digits. The injured limb segment was lost or beyond repair in 387 cases (18% of all cases). In the 1,794 remaining injuries, primary treatment was accomplished by end-to-end suture 1,568 times (87%) and by graft 33 times (> 2%) and was impossible in 193 cases (11%).     

Pulmonary agenesis with intrathoracic upper limb

A 10-week-old boy was referred because of respiratory distress, absence of right upper limb, and a mass in the right upper chest and shoulder region. Investigations showed agenesis of the right lung; the right hemithorax was filled by a mass that was mainly cystic but also contained a deformed right upper limb. When surgery was performed at the age of 13 weeks, the mass was delivered out of the chest and removed together with the deformed limb. The upper 5 cm of the shaft of the humerus could be preserved, and the chest wall could be repaired satisfactorily. Recovery was uneventful. The embryology of the malformation is briefly discussed.     

Psychological distress in workers with traumatic upper or lower limb amputations following industrial injuries.

Objective: To determine whether individuals with traumatic upper limb amputations would report more symptoms of posttraumatic stress disorder (PTSD) and depression than individuals with traumatic lower limb amputations. Study Design: Retrospective file review. Setting: CARF-accredited outpatient rehabilitation center. Participants: Thirty workers with unilateral upper limb amputations and 25 workers with unilateral lower limb amputations. Main Outcome Measures: Presence or absence of depression, symptoms of PTSD, and pain. Results: The upper limb group had a higher frequency of depression and symptoms of PTSD than the lower limb group. The 2 groups did not differ with respect to pain complaints. Conclusion: More so than injuries to the lower limbs, upper limb injuries may render individuals vulnerable to PTSD and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Possible role of glutathione in prevention of acetaminophen-induced hepatotoxicity enhanced by fish oil in male Wistar rats

Two-limb coordination of homologous and non-homologous effectors was examined during isofrequency (1:1) and multifrequency (2:1) conditions. The coordination patterns involved flexion and extension movements in the sagittal plane and were performed under unloaded and single-limb (right arm) loaded conditions. Previous studies suggested that the lower degree of 1:1 synchronization observed during nonhomologous as compared to homologous coordination results from natural differences in biophysical (inertial) properties. Elaborating on this idea, adding weight to the right arm was hypothesized to modulate its inertial characteristics, rendering homologous limbs more dissimilar and nonhomologous limbs more similar by enhancing and decreasing their inertial differences, respectively. Therefore, the observations made during unloaded conditions were predicted to be completely reversed during loaded conditions. Findings revealed that during 1:1 coordination (experiment 1) single-limb loading resulted in a decreased relative phase stability, whereas relative phase accuracy depended upon the limb combination. In particular, phase-locking was more accurately maintained for loaded homologous than for nonhomologous limbs, whereas loading the nonhomologous limbs resulted in a deterioration of the quality of synchronization. These findings suggest that there is an additional explanation of differential coordination capabilities among limb combinations. It is hypothesized that the neural networks subserving the control centers of the homologous limbs are more tightly connected than those of the nonhomologous effectors, allowing 1:1 synchronization to be more successfully preserved in the face of (load) perturbations. During 2:1 coordination (experiment 2), the loading procedure disturbed the coordination dynamics across all limb combinations. That no differential effect of loading on effector combination was observed is possibly a result of the fact that only an initial level of practice was studied in which optimal relative phase dynamics are still being explored for both homologous and nonhomologous limbs.     

Quality of life after transthoracic endoscopic sympathectomy for upper limb hyperhidrosis

OBJECTIVE: To assess the outcome after transthoracic endoscopic sympathectomy (TES) for upper limb hyperhidrosis. DESIGN: Prospective cohort study. SETTING: District general hospital. SUBJECTS: Consecutive patients undergoing TES for upper limb hyperhidrosis over a fifteen month period. INTERVENTIONS: One-stage bilateral TES. MAIN OUTCOME MEASURES: Change in quality of life as shown by the Short Form-36 health assessment questionnaire. RESULTS: Sixteen patients (11 women and 5 men, median age 26 years) underwent operation without complications. At median follow-up of 6.2 months, symptomatic improvement was found in 26 of 32 limbs treated (82%). Truncal compensatory hyperhidrosis was reported by 13 patients but was severe in only three. There were significant improvements in social function (p = 0.01) and mental health (p = 0.025) as assessed by the SF-36. CONCLUSION: Despite a high incidence of compensatory hyperhidrosis, TES improved both the symptoms and overall quality of life in patients with upper limb hyperhidrosis.     

Kinematics of locomotion by cats with a single hindlimb deafferented

1. Cinematographic measurements were made of stepping by cats on a motor-driven treadmill, both normally and 2-3 wk after deafferentation of the LH (left hind) limb. 2. After surgery, rhythmic cycling of the LH limb was blurred whether the leg was dragged, as by some cats, or if it was lifted from the surface, as by others. 3. Interlimb coordination was also blurred with respect to normal, although distinct rhythms were still seen. The RH (right hind) limb descended prematurely and, in the walk, had a prolonged stance phase. The interval between touchdowns of hind- and forelimb on the left side no longer equaled that interval on the right side. 4. As is true for a normal cat, if the LH-deafferented animal stumbled, relatively normal single and interlimb cyclings were regained after several strides. 5. By kinematic analysis, force deficits were found in the deafferented LH limb both during the stance, when extensors should be most active, and the swing, when the limb failed to attain a normal position above the surface of the belt. Weight bearing by the LF (left fore) limb was altered in some animals. 6. At high speed, mean LH stance duration failed to decrease in the normal fashion. Inter-limb timings were reset to greater extent than in low-speed walking, as if the LH limb was being used only minimally. 7. It was concluded that both rhythm and force were impaired in the deafferented limb and also in the three intact limbs, whose weight bearing had to compensate for LH weakness. The changed mechanical demands after surgery were probably met by interactions between the remaining afferent input and central pattern generators so as to secure fairly effective and expedient locomotion.     

A family with neurogenic atrophy of the distal muscles of the upper limbs: clinical and electrophysiological studies

A Chinese family manifested mild neurogenic atrophy of the distal muscles of the upper limbs. None of the affected members had sensory abnormalities, or pyramidal tract or bulbar involvement. The onset of the illness was in the middle of the second decade of life. The muscle atrophy was more severe in the female members. Electromyographic examination of the atrophic muscles showed evidence denervation. One female patient demonstrated slow motor conduction velocity in the right median nerve.     

A clinical, MRI and neurophysiological study of acute transverse myelitis

There is paucity of studies correlating the MRI and evoked potential changes in acute transverse myelitis (ATM). We studied ten patients with ATM (age range 14-57 years; 8 men, 2 women) who were subjected to clinical, MRI and neurophysiological evaluation. The latter included median and tibial somatosensory evoked potentials (SEP), motor evoked potentials (MEP) to upper and lower limbs and concentric needle EMG. The outcome was defined on the basis of three month Barthel Index score. All the patients had pronounced lower limb and three had upper limb weakness. Magnetic resonance imaging scans revealed diffuse to hypointense lesions in T1, which became hyperintense in T2 in all except one patient, who had patchy hyperintense lesions in both T1 and T2 sequences suggesting haemorrhage. The signal changes extended at least three segments above the sensory level. Tibial SEP and central motor conduction time to tibialis anterior (CMCT-TA) were abnormal in nine patients each. Median SEP was normal in all, but CMCT to abductor digiti minimi (CMCT-ADM) was abnormal in four patients. The extent of MRI signal alterations and CMCT-TA correlated with the outcome. Seven patients had a poor outcome, in them MRI changes extended 10 spinal segments or more. In these patients, MEP on lumbar stimulation was either unrecordable or of low amplitude and extensive fibrillations were present in the lower limb muscles. From this study, we conclude that in ATM, extensive MRI changes, unrecordable MEP to lower limbs especially on lumbar stimulation and evidence of denervation in leg muscles seem to predict a poor outcome.     

Relationship between dose, distance and time in Sonic Hedgehog-mediated regulation of anteroposterior polarity in the chick limb

Anteroposterior polarity in the vertebrate limb is thought to be regulated in response to signals derived from a specialized region of distal posterior mesenchyme, the zone of polarizing activity. Sonic Hedgehog (Shh) is expressed in the zone of polarizing activity and appears to mediate the action of the zone of polarizing activity. Here we have manipulated Shh signal in the limb to assess whether it acts as a long-range signal to directly pattern all the digits. Firstly, we demonstrate that alterations in digit development are dependent upon the dose of Shh applied. DiI-labeling experiments indicate that cells giving rise to the extra digits lie within a 300 microm radius of a Shh bead and that the most posterior digits come from cells that lie very close to the bead. A response to Shh involves a 12-16 hour period in which no irreversible changes in digit pattern occur. Increasing the time of exposure to Shh leads to specification of additional digits, firstly digit 2, then 3, then 4. Cell marking experiments demonstrate that cells giving rise to posterior digits are first specified as anterior digits and later adopt a more posterior character. To monitor the direct range of Shh signalling, we developed sensitive assays for localizing Shh by attaching alkaline phosphatase to Shh and introducing cells expressing these forms into the limb bud. These experiments demonstrate that long-range diffusion across the anteroposterior axis of the limb is possible. However, despite a dramatic difference in their diffusibility in the limb mesenchyme, the two forms of alkaline phosphatase-tagged Shh proteins share similar polarizing activity. Moreover, Shh-N (aminoterminal peptide of Shh)-coated beads and Shh-expressing cells also exhibit similar patterning activity despite a significant difference in the diffusibility of Shh from these two sources. Finally, we demonstrate that when Shh-N is attached to an integral membrane protein, cells transfected with this anchored signal also induce mirror-image pattern duplications in a dose-dependent fashion similar to the zone of polarizing activity itself. These data suggest that it is unlikely that Shh itself signals digit formation at a distance. Beads soaked in Shh-N do not induce Shh in anterior limb mesenchyme ruling out direct propagation of a Shh signal. However, Shh induces dose-dependent expression of Bmp genes in anterior mesenchyme at the start of the promotion phase. Taken together, these results argue that the dose-dependent effects of Shh in the regulation of anteroposterior pattern in the limb may be mediated by some other signal(s). BMPs are plausible candidates.     

Ground reaction force patterns of Dutch Warmbloods at the canter

Ground reaction force (GRF) patterns from 20 clinically sound Dutch Warmbloods were recorded at the right fore-leading canter, and a standard horse was composed. These GRF data for the standard can be used for evaluation of jumping horses. The GRF patterns were asymmetric for all 4 limbs. The leading right forelimb decelerated the body. The trailing left forelimb propelled the body and decelerated it slightly. The trailing left hind limb propelled, and the leading right hind limb contributed to deceleration and propulsion. Referred to the maximal vertical load of the leading right forelimb, the load of the trailing left forelimb was 25% more; the load of the right hind limb was slightly less, whereas the load of the left hind limb was about 80% of that value.     

Review of 23 patients affected by the stiff man syndrome: clinical subdivision into stiff trunk (man) syndrome, stiff limb syndrome, and progressive encephalomyelitis with rigidity

OBJECTIVE: To investigate whether the stiff limb syndrome may be separated from the stiff man syndrome and progressive encephalomyelitis with rigidity on simple clinical grounds, and whether such a distinction has implications for aetiology, treatment, and prognosis. METHODS: Twenty three patients referred over a 10 year period with rigidity and spasms in association with continuous motor unit activity, but without evidence of neuromyotonia, extrapyramidal or pyramidal dysfunction or focal lesions of the spinal cord were reviewed. The patients were divided into those with an acute or subacute illness, leading to death within 1 year, and those with a chronic course. The latter were divided into those in whom rigidity and spasms dominated in the axial muscles, or in one or more distal limbs, at the time of their first assessment. RESULTS: This simple division identified three distinct groups of patients. (1) Progressive encephalomyelitis with rigidity: two patients had a rapidly progressive condition characterised by widespread rigidity which resulted in death within 6 and 16 weeks. One patient had negative anti-GAD and anti-neuronal antibodies, but had markedly abnormal CSF and widespread denervation. The principal pathological findings in this case were a subacute encephalomyelitis which primarily affected the grey matter. In the remaining patient anti-GAD antibodies were not tested, and postmortem was refused. (2) Stiff man syndrome: eight patients had rigidity and painful spasms of the lumbar paraspinal, abdominal, and occasionally proximal leg muscles associated with a lumbar hyperlordosis. There was no involvement of the upper limbs, distal lower limbs, sphincters or cranial nerves. Seven had anti-GAD antibodies and most had additional evidence of autoimmune disease. Neurophysiologically there was continuous motor unit activity with abnormal exteroceptive reflexes, but a normal interference pattern during spasms. The patients all responded to baclofen/diazepam and remained ambulant. (3) Stiff limb syndrome: thirteen patients had rigidity, painful spasm, and abnormal postures of the distal limb, ususphincter or brainstem involvement. Generalised myoclonic jerks were not a feature. Only two had truncal rigidity, and another two had anti-GAD antibodies. Most had no evidence of autoimmune disease. Neurophysiologically they had continuous motor unit activity in the affected limb, abnormal exteroceptive reflexes, and abnormally segmented EMG activity during spasms. The disease ran a protracted course, and most patients had only a partial response to baclofen or diazepam. About half became wheelchair bound. CONCLUSIONS: The stiff limb syndrome seems distinct from the stiff man syndrome or progressive encephalomyelitis with rigidity, and is an important cause of rigidity and spasm in the setting of continuous motor unit activity.     

Diagnosis of "non-organic" limb paresis by a novel objective motor assessment: the quantitative Hoover's test

The differentiation of "non-organic" limb weakness from genuine paralysis is sometimes difficult in neurological practice. To address this problem, we developed a computerized quantitative method, based on the Hoover's test principle, that determines the extent of involuntary limb activation when contralateral movement is performed. Measurements of hip or arm extension isometric force are performed during direct maximal voluntary effort and during contralateral hip flexion. Maximal involuntary/voluntary force ratio (IVVR) is calculated. IVVR of the lower limbs in ten healthy subjects was 0.614, 0.044 (mean, SEM). Similar results were obtained from seven patients with genuine weakness and in the non-affected limbs of nine patients with "non-organic" mono- or hemiparesis. In contrast, IVVR in the affected limbs in the "non-organic" group was markedly increased (2.48, 0.61; P < 0.001). The same pattern was elicited in the upper limbs (2.27, 0.46 vs 0.406, 0.06; P < 0,001). We conclude that Hoover's sign in "nonorganic" paralysis is a preservation or increase of a normal synkinetic phenomenon. Quantitative measurement of the IVVR can serve as a useful ancillary test in diagnosing non-organic weakness in either lower or upper limbs.     

Caries in patients with non-insulin-dependent diabetes mellitus

OBJECTIVE: To describe intratrial differences in hind limb symmetry in healthy dogs at the trot, using noninvasive, computer-assisted, three-dimensional kinematic gait analysis. ANIMALS: 8 clinically normal large-breed adult dogs. PROCEDURE: Dynamic flexion and extension angles and angular velocities were calculated for the coxofemoral, femorotibial, and tarsal joints of dogs at the trot. Temporal and distance variables were computed. Essential Fourier coefficients were used to determine mean flexion and extension curves for all joints and to compare differences in movement between right and left hind limbs. Variances attributable to limb, dog, and trial were determined. RESULTS: Each joint had a characteristic pattern of flexion and extension movement that was used to compare intratrial symmetry of hind limb gait. Significant differences were not detected in temporal or distance variables between the right and left hind limbs. Significant differences were not noted in essential Fourier coefficients used to characterize coxofemoral, femorotibial, and tarsal joint angles and angular velocities, with the exception of the cosine-0 coefficient for coxofemoral angular velocity. Variation in joint angle and angular velocity measurements were attributable to individual dog and trial. Variation attributable to limb was negligible. CONCLUSIONS: Intratrial evaluation of right-left hind limb symmetry, using kinematic gait analysis, indicated objectively that hind limb movement is symmetrical at the trot in healthy large-breed dogs. CLINICAL RELEVANCE: Documentation of hind limb symmetry at the trot will help provide a basis for direct comparison of both hind limbs in future studies evaluating gait and treatment of dogs with musculoskeletal disease.