Peripheral Nerve Injury Induces Immediate Increases in Layer v Neuronal Activity.

Peripheral Nerve Injury Induces Immediate Increases in Layer V Neuronal Activity.

Neurorehabil Neural Repair. 2013 Apr 18;
Han Y, Li N, Zeiler SR, Pelled G

BACKGROUND: . Peripheral nerve injury leads to changes in neuronal activity in the contralateral and ipsilateral primary somatosensory cortices (S1), which may lead to enduring sensory dysfunction and pain. Plasticity in the barrel and visual cortices has been shown to occur in a layer-specific manner. However, little is known about the layer specific changes associated with limb injury. OBJECTIVE: . To determine the layer-specific changes in neuronal activity associated with short-term plasticity induced by peripheral nerve injury in the rat. METHODS: . In vivo electrophysiology recordings (multiunit activity and local field potential) and high-resolution functional magnetic resonance imaging techniques were applied to characterize neuronal and hemodynamic responses across the depth of S1 contralateral and ipsilateral to the injury. RESULTS: . Within 60 minutes following injury, atypical increases in neuronal and hemodynamic responses in the deprived S1, ipsilateral to the noninjured limb, were observed in response to stimulation of the noninjured limb. The most prominent increases in neuronal activity in the deprived S1 occurred in layer V. CONCLUSION: . Layer V neurons provide the major output of S1 and they send and receive transcallosal input. Thus, the immediate changes in neuronal firing patterns in layer V induced by the injury, can adversely affect the activity of subcortical regions and also interfere with normal cortical processing and interhemispheric communication. Therefore, a rehabilitation strategy that targets layer V neurons activity and starts immediately after the injury may benefit the functional outcome. HubMed – rehab

Bilateral isolated cut of sensory branch of radial nerve.

Ulus Travma Acil Cerrahi Derg. 2013 Mar; 19(2): 186-188
Akkaya N, Ozcan HR, Gökalan Kara I, Sahin F

Bilateral injuries of the sensory branch of the radial nerve (SBRN) usually occur as a result of tight-handcuff neuropathy. In this case we aimed to present bilateral isolated cut of SBRN resulting an injury mechanism that has not been reported in the literature previously. A male twenty-four years old, a worker in a glass factory, presented to our clinic. The dorsolateral skin of his wrists were cut by breaking of the glass as a result of occupational accident and was primarily sutured in a healthcare center. The patient sought additional care after a month because of lingering numbness and pain, and surgery was planned. During surgery, scar tissue and neuroma at the cut ends of SBRN were excised, and bilateral SBRN cuts were repaired. Four weeks after operation, mild sensory deficit on the dorsal side of bilateral thumbs, and left first web space and flexion limitation on the right wrist were detected. At the 3rd month postoperative, right wrist joint range of motion was full, and sensory deficits, and hyperesthesia were decreased. The SBRN elicits the sensory innervation of the thumb dorsum and its injury does not cause important functional deficit. However because of susceptibility of SBRN to develop painful neuroma, diagnosis, treatment and follow up of isolated SBRN injury would be worthwhile for prevention of possible painful neuropathy disturbing quality of life. HubMed – rehab

Phantom shocks in patients with implantable cardioverter defibrillator: results from a randomized rehabilitation trial (COPE-ICD).

Europace. 2013 Apr 18;
Berg SK, Moons P, Zwisler AD, Winkel P, Pedersen BD, Pedersen PU, Svendsen JH

AIMS: The aim of this trial was to assess a combined rehabilitation intervention including an exercise training component and a psycho-educational component in patients treated with implantable cardioverter defibrillator (ICD). The hypothesis was that the intervention would reduce the occurrence of phantom shocks.METHODS AND RESULTS: The design was secondary explorative analyses of data from a randomized controlled trial. One hundred and ninety-six patients with first-time ICD implantation (79% male, mean age 58 years) were randomized (1 : 1) to either combined rehabilitation or a control group receiving ‘treatment as usual’. A total of 144 participants completed the 12-month follow-up. Intervention consisted of 12 weeks of exercise training and 1 year of psycho-educational follow-up focusing on modifiable factors associated with poor outcomes, e.g. phantom shocks. Outcome measures were ancillary questions regarding the experience of phantom shocks, date, time, and place. Twelve patients (9.4%) experienced a phantom shock, 7 in the intervention group and 5 in the control group (NS). Neither age, sex, quality of life nor perceived health at baseline was significantly related to the probability of occurrence of phantom shock.CONCLUSION: Phantom shocks were experienced by about one in ten ICD patients, with no interventional effect found and no significant difference found regarding receiving an actual shock therapy among phantom shock patients.: Trial registration: ClinicalTrials.gov (ID: NCT00569478). HubMed – rehab

Computer-Assisted Implant Rehabilitation of Maxillomandibular Defects Reconstructed With Vascularized Bone Free Flaps.

JAMA Otolaryngol Head Neck Surg. 2013 Apr 1; 139(4): 371-381
Okay DJ, Buchbinder D, Urken M, Jacobson A, Lazarus C, Persky M

IMPORTANCE Functional recovery for patients who undergo maxillomandibular reconstruction with vascularized bone free flaps (VBFFs) is potentially more attainable with computer-assisted implant rehabilitation. This prosthodontic-driven approach uses software planning and surgical templates for implant placement supporting fixed dental prostheses (FDP). Implant success with immediate load (IL) provisional and definitive FDP restorations in VBFFs is reported for the first time in a patient cohort. OBJECTIVES To determine implant success for FDP restorations and IL restorations. To determine factors that may influence success and predictability to provide FDP restorations in VBFFs. DESIGN A retrospective medical chart review was conducted of patients who underwent VBFF reconstruction and computer-assisted planning (CP) for FDP implant rehabilitation. This study was conducted with approval from the institutional review board at Beth Israel Medical Center, New York, New York. SETTING Clinical procedures were conducted in operating room and outpatient facilities in a tertiary referral medical center. PARTICIPANTS Twenty-eight consecutive patient treatments were reviewed. Inclusion criteria for all patients were VBFF reconstruction and CP for FDP restoration prior to stage 1 implant surgery. Patients were evaluated for implant success, surgical templates, IL provisional restorations, and prosthodontic framework design. A comparison is made between patients with IL provisional restorations and those patients who did not receive an immediate restoration. MAIN OUTCOMES AND MEASURES Implants that achieved osseointegration and used for prosthetic reconstruction determined success. Prosthodontic design considerations included whether the patient received an IL provisional restoration and 3 categories of FDP metal framework design. RESULTS Ninety-nine implants of 116 implants placed were used for prosthetic restorations, achieving an 85.4% success rate. Twenty-five of 28 patients received FDP restorations. Thirteen of 28 patients received IL provisional restorations at stage 1 implant surgery. Fifty of 56 implants were successful (89.3%) in the IL group. CONCLUSIONS Computer-assisted implant rehabilitation of reconstructed defects can achieve superior results to provide FDP and IL provisional restorations. This prosthodontic-driven approach also uses unique framework design to account for mandible height discrepancy after fibula free flap reconstruction. Patient management for FDP rehabilitation is also dependent on radiation status, soft-tissue modification, and patient selection. HubMed – rehab

Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells in the Cultured Rabbit Intervertebral Disc: A Novel Cell Source for Disc Repair.

Am J Phys Med Rehabil. 2013 May; 92(5): 420-429
Anderson DG, Markova D, An HS, Chee A, Enomoto-Iwamoto M, Markov V, Saitta B, Shi P, Gupta C, Zhang Y

OBJECTIVE: Back pain associated with symptomatic disc degeneration is a common clinical condition. Intervertebral disc (IVD) cell apoptosis and senescence increase with aging and degeneration. Repopulating the IVD with cells that could produce and maintain extracellular matrix would be an alternative therapy to surgery. The objective of this study was to determine the potential of human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) as a novel cell source for disc repair. In this study, we intended to confirm the potential for hUCB-MSCs to differentiate and display a chondrocyte-like phenotype after culturing in micromass and after injection into the rabbit IVD explant culture. We also wanted to confirm hUCB-MSC survival after transplantation into the IVD explant culture. DESIGN: This study consisted of micromass cultures and in vitro rabbit IVD explant cultures to assess hUCB-MSC survival and differentiation to display chondrocyte-like phenotype. First, hUCB-MSCs were cultured in micromass and stained with Alcian blue dye. Second, to confirm cell survival, hUCB-MSCs were labeled with an infrared dye and a fluorescent dye before injection into whole rabbit IVD explants (host). IVD explants were then cultured for 4 wks. Cell survival was confirmed by two independent techniques: an imaging system detecting the infrared dye at the organ level and fluorescence microscopy detecting fluorescent dye at the cellular level. Cell viability was assessed by staining the explant with CellTracker green, a membrane-permeant tracer specific for live cells. Human type II collagen gene expression (from the graft) was assessed by polymerase chain reaction. RESULTS: We have shown that hUCB-MSCs cultured in micromass are stained blue with Alcian blue dye, which suggests that proteoglycan-rich extracellular matrix is produced. In the cultured rabbit IVD explants, hUCB-MSCs survived for at least 4 wks and expressed the human type II collagen gene, suggesting that the injected hUCB-MSCs are differentiating into a chondrocyte-like lineage. CONCLUSIONS: This study demonstrates the abiity of hUBC-MSCs to survive and assume a chondrocyte-like phenotype when injected into the rabbit IVD. These data support the potential for hUBC-MSCs as a cell source for disc repair. Further measures of the host response to the injection and studies in animal models are needed before trials in humans. HubMed – rehab