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Birgitta Rosen - One of the best experts on this subject based on the ideXlab platform.
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Functional outcome thirty years after median and ulnar Nerve Repair in childhood and adolescence.
Journal of Bone and Joint Surgery American Volume, 2013Co-Authors: Anette Chemnitz, Lars B Dahlin, Anders Björkman, Birgitta RosenAbstract:Age at injury is believed to be a factor that strongly influences functional outcome after Nerve injury. However, there have been few long-term evaluations of the results of Nerve Repair and reconstruction in children. Our aim was to evaluate the long-term functional outcome of Nerve Repair or reconstruction at the forearm level in patients with a complete median and/or ulnar Nerve injury at a young age.
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hand function after Nerve Repair
Acta Physiologica, 2007Co-Authors: Goran Lundborg, Birgitta RosenAbstract:Treatment of injuries to major Nerve trunks in the hand and upper extremity remains a major and challenging reconstructive problem. Such injuries may cause long-lasting disabilities in terms of lost fine sensory and motor functions. Nowadays there is no surgical Repair technique that can ensure recovery of tactile discrimination in the hand of an adult patient following Nerve Repair while very young individuals usually regain a complete recovery of functional sensibility. Post-traumatic Nerve regeneration is a complex biological process where the outcome depends on multiple biological and environmental factors such as survival of Nerve cells, axonal regeneration rate, extent of axonal misdirection, type of injury, type of Nerve, level of the lesion, age of the patient and compliance to training. A major problem is the cortical functional reorganization of hand representation which occurs as a result of axonal misdirection. Although protective sensibility usually occurs following Nerve Repair, tactile discriminative functions seldom recover - a direct result of cortical remapping. Sensory re-education programmes are routinely applied to facilitate understanding of the new sensory patterns provided by the hand. New trends in hand rehabilitation focus on modulation of central nervous processes rather than peripheral factors. Principles are being evolved to maintain the cortical hand representation by using the brain capacity for visuo-tactile and audio-tactile interaction for the initial phase following Nerve injury and Repair (phase 1). After the start of the re-innervation of the hand (phase 2), selective de-afferentation, such as cutaneous anaesthesia of the forearm of the injured hand, allows expansion of the Nerve-injured cortical hand representation, thereby enhancing the effects of sensory relearning. Recent data support the view that training protocols specifically addressing the relearning process substantially increase the possibilities for improved functional outcome after Nerve Repair.
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sensory relearning after Nerve Repair
The Lancet, 2001Co-Authors: Goran Lundborg, Birgitta RosenAbstract:Summary One of the challenges in reconstructive surgery is to ensure hand sensibility is regained after median Nerve Repair. We assessed tactile gnosis in 54 patients (mean age 32 [range 4–72] years) after Repair of transected median or ulnar Nerves at the wrist level. We found that there is a well-defined critical period for sensory relearning after Nerve Repair. There is an optimum capacity below age 5–10 years followed by a rapid decline, which levels out after puberty. The curve correlates with previously published data on critical periods for language acquisition among immigrants. Recovery of functional sensibility after Nerve Repair is based on a learning process and in many ways is analogous to learning a second language.
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a model instrument for the documentation of outcome after Nerve Repair
Journal of Hand Surgery (European Volume), 2000Co-Authors: Birgitta Rosen, Goran LundborgAbstract:Abstract We present a new model for documentation and quantification of the functional outcome after Nerve Repair at the wrist or distal forearm level and a protocol that includes a numerical scoring system. The model, presented here along with validation and reliability test results, supports our hypothesis that the summarized test results reflecting specific functional limitations correlates well with the patient's opinion of the impact of the Nerve injury on activities of daily living. Seventy patients with Nerve Repair were examined using the protocol. Analysis included 3 factors: sensory domain (sensory innervation, tactile gnosis, and finger dexterity), motor domain (motor innervation and grip strength), and pain/discomfort domain (hyperaesthesia and cold intolerance). The analysis explained 73% of the variances of the variables and the variables had a logical distribution between the factors. Analysis of internal consistency demonstrated good homogeneity. A calculated total score correlated strongly with the patients' global estimation of the impact of the injury on activities of daily living and the summary of sensory and pain/discomfort domains correlated significantly with the Medical Research Council S0–S4 scale. The presented model represents a useful new tool for evaluation of the functional outcome after Nerve injury and Repair. (J Hand Surg 2000;25A:535–543. Copyright © 2000 by the American Society for Surgery of the Hand.)
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Recovery of Sensory and Motor Function After Nerve Repair: A Rationale for Evaluation
Journal of Hand Therapy, 1996Co-Authors: Birgitta RosenAbstract:Abstract In order to identify an effective, test for evaluating the results of Nerve Repair, 25 patients, age 10–53 years (mean 27 years), were evaluated two to five years after median or ulnar Nerve Repair at the distal forearm level. The initial assumption was that evaluation after Nerve Repair should reflect four aspects of recovery: reinnervation, tactile gnosis, integrated sensory and motor functions, and pain or discomfort. The evaluation included a number of assessment methods addressing these aspects. Attention was paid to the usefulness of the tests with reference to their relevance for assessing hand functions. Clinical utility and possibilities for standardization and quantification of the results were considered important. Statistical analysis showed no correlations between the results obtained in clinical tests for reinnervation and the results from neurophysiologic examination. Grip strength and cold intolerance together accounted for a significant 51% of the variance in activities of daily living (ADL) capacity. Tactile gnosis correlated weakly with ADL capacity and strongly with age. Based on these findings, the following design for evaluating the result after median and ulnar Nerve Repair is suggested. To assess reinnervation: Semmes-Weinstein monofilaments and manual muscle-testing; to assess tactile gnosis: classic 2PD and a test with the features of the used shape identification test; to assess integrated functions: selected parts of Sollerman's grip test and grip-strength test with Jamar dynamometer; to quantify pain and discomfort: a four-ranked scale for grading perceived problems from cold intolerance and hypersensitivity.
Susan E. Mackinnon - One of the best experts on this subject based on the ideXlab platform.
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End-to-side Nerve Repair: Review of the literature
Restorative Neurology and Neuroscience, 2020Co-Authors: Christopher J. Pannucci, Susan E. Mackinnon, Terence M. Myckatyn, Ayato HayashiAbstract:End-to-side (ETS) Nerve Repair, in which the distal stump of a transected Nerve is coapted to the side of an uninjured donor Nerve, offers a technique for Repair of peripheral Nerve injuries where the proximal Nerve stump is unavailable or a significant Nerve gap exists. Details of animal models are explored including motor and sensory regeneration to further clarify the mechanism of collateral sprouting while eliminating false positive results from contaminating axons. Some experimental studies support the conclusion that sensory or motor reinnervation may be derived from collateral sprouting while others suggest that reinnervation requires an injury to the donor Nerve. Clinical experience with ETS neurorrhaphy includes management of upper extremity Nerve injury, facial reanimation, reconstruction following tumor ablation, and the prevention of neuroma formation. Our interpretation of the ETS literature suggests that sensory axons may sprout without deliberately attempting to injure them, while motor axons regenerate only in response to a deliberate injury. Experimental and clinical experience with ETS neurorrhaphy has rendered mixed results. Our interpretation of the literature suggests that the success of this technique is dependent upon axonal injury of motor and possibly sensory Nerves. While continued clinical and laboratory experimentation with ETS Nerve Repair is warranted, it should not yet replace more established techniques of Nerve Repair.
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Delayed Nerve Repair is associated with diminished neuroenhancement by FK506
2020Co-Authors: Michael J. Brenner, David H. Kawamura, Vivian M. Yu, James B. Lowe, Daniel A. Hunter, Susan E. MackinnonAbstract:Objectives/Hypothesis: The immunosuppressive agent FK506 has been shown in many studies to enhance Nerve regeneration and to accelerate functional recovery after immediate Nerve Repair. However, in clinical practice the diagnosis and treatment of patients with peripheral Nerve injuries is often delayed. The study investigated whether FK506 would retain its neuroregenerative properties when Nerve Repair and initiation of FK506 therapy were delayed for 7 days. Study Design: In vivo laboratory study. Methods: Thirty-two Lewis rats underwent tibial Nerve transection and were randomly assigned to four experimental groups: immediate Repair with FK506 treatment, immediate Repair without FK506 treatment, 7-day delayed Repair with FK506 treatment, and 7-day delayed Repair without FK506 treatment. Treated animals received daily subcutaneous injections of 2 mg/kg FK506. Serial walking track measurements were performed at 14, 16, and 18 days after Nerve Repair. On day 18 after Repair, peripheral Nerves were injected with a fluorescent tracer for retrograde labeling. On day 21, peripheral Nerves and spinal cords were harvested for histomorphometric analysis and motor neuron cell body counts, respectively. Results: Animals that underwent immediate Repair with FK506 had significantly higher fiber counts and percentages of Nerve than the other three groups (P
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The role of microsurgery in Nerve Repair and Nerve grafting.
Hand Clinics, 2007Co-Authors: Linda Dvali, Susan E. MackinnonAbstract:Advances in the field of microsurgery have improved the results after peripheral Nerve surgery and have extended the types of Nerve Repair that can be accomplished. Innovative techniques using microsurgical dissection, such as Nerve transfers and end-to-side Repairs are direct consequences of these advances.
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Delayed Nerve Repair Is Associated With Diminished Neuroenhancement by FK506
Laryngoscope, 2004Co-Authors: Michael J. Brenner, David H. Kawamura, Vivian M. Yu, James B. Lowe, Daniel A. Hunter, Susan E. MackinnonAbstract:Objectives/Hypothesis The immunosuppressive agent FK506 has been shown in many studies to enhance Nerve regeneration and to accelerate functional recovery after immediate Nerve Repair. However, in clinical practice the diagnosis and treatment of patients with peripheral Nerve injuries is often delayed. The study investigated whether FK506 would retain its neuroregenerative properties when Nerve Repair and initiation of FK506 therapy were delayed for 7 days. Study Design In vivo laboratory study. Methods Thirty-two Lewis rats underwent tibial Nerve transection and were randomly assigned to four experimental groups: immediate Repair with FK506 treatment, immediate Repair without FK506 treatment, 7-day delayed Repair with FK506 treatment, and 7-day delayed Repair without FK506 treatment. Treated animals received daily subcutaneous injections of 2 mg/kg FK506. Serial walking track measurements were performed at 14, 16, and 18 days after Nerve Repair. On day 18 after Repair, peripheral Nerves were injected with a fluorescent tracer for retrograde labeling. On day 21, peripheral Nerves and spinal cords were harvested for histomorphometric analysis and motor neuron cell body counts, respectively. Results Animals that underwent immediate Repair with FK506 had significantly higher fiber counts and percentages of Nerve than the other three groups (P < .05) but did not show statistically significant earlier functional recovery. The remaining three groups had intermediate levels of Nerve regeneration that were not significantly different. Retrograde abled motor neurons counts were decreased in animals with delayed Nerve Repair that received no FK506 (P < .05). Conclusion In a rat tibial Nerve transection model, the neuroregenerative effects of FK506 diminished markedly when Repair and initiation of FK506 therapy were delayed by 7 days.
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Nerve Repair grafting and Nerve transfers
Clinics in Plastic Surgery, 2003Co-Authors: Linda Dvali, Susan E. MackinnonAbstract:Advances in the field of peripheral Nerve surgery have increased our understanding of the complex cellular and molecular events involved in Nerve injury and Repair. Application of these discoveries has led to important developments in the techniques of Nerve Repair, Nerve grafting, and Nerve-to-Nerve transfers. This article reviews the principles and techniques of Nerve Repair and discusses the options available when direct Repair cannot be performed, including Nerve grafts, conduits, end-to-side Repair, and Nerve-to-Nerve transfers. As our understanding of this dynamic field increases, further improvement in functional outcomes after Nerve injury and Repair can be expected.
Lars B Dahlin - One of the best experts on this subject based on the ideXlab platform.
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Functional recovery and mechanisms in end-to-side Nerve Repair in rats
Acta Neurochirurgica, 2020Co-Authors: Lars B Dahlin, E Bontioti, K Kataoka, Martin KanjeAbstract:BACKGROUND: End-to-side Nerve Repair is attachment of a single distal Nerve segment (recipient Nerve) end-to-side to an intact donor Nerve when there is a lack of proximal Nerve segment after injury. The technique is currently used clinically but the mechanism(s) behind this technique are essentially unknown. METHODS: We have studied end-to-side Nerve Repair in the forelimb of rats, where a single distal radial Nerve or an ulnar or a median, or both, Nerves are attached end-to-side to an intact musculocutaneous Nerve. We have studied functional recovery, origin of the regenerating axons and cell activation by the end-to-side Nerve Repair. FINDINGS: Functional recovery occurs after end-to-side Nerve Repair but is less sufficient than conventional end-to-end Nerve Repair or a Nerve graft procedure. Sensory and motor axons grow from the musculocutaneous Nerve out into the attached Nerve segment(s). An injury is required to the musculocutaneous Nerve to activate sensory and motor neurons as well as Schwann cells in the musculocutaneous Nerve for initiation of regeneration. CONCLUSIONS: End-to-side Nerve Repair may be an alternative method in specific cases of complex Nerve injuries to reconstruct Nerve trunks when no other Repair options are possible. Some functional recovery does occur but regeneration of sensory and motor axons require an injury to the neurons of the donor Nerve. (Less)
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Functional outcome thirty years after median and ulnar Nerve Repair in childhood and adolescence.
Journal of Bone and Joint Surgery American Volume, 2013Co-Authors: Anette Chemnitz, Lars B Dahlin, Anders Björkman, Birgitta RosenAbstract:Age at injury is believed to be a factor that strongly influences functional outcome after Nerve injury. However, there have been few long-term evaluations of the results of Nerve Repair and reconstruction in children. Our aim was to evaluate the long-term functional outcome of Nerve Repair or reconstruction at the forearm level in patients with a complete median and/or ulnar Nerve injury at a young age.
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techniques of peripheral Nerve Repair
Scandinavian Journal of Surgery, 2008Co-Authors: Lars B DahlinAbstract:Nerve injuries extend from simple Nerve compression lesions to complete Nerve injuries and severe lacerations of the Nerve trunks. A specific problem is brachial plexus injuries where Nerve roots can be ruptured, or even avulsed from the spinal cord, by traction. An early and correct diagnosis of a Nerve injury is important. A thorough knowledge of the anatomy of the peripheral Nerve trunk as well as of basic neurobiological alterations in neurons and Schwann cells induced by the injury are crucial for the surgeon in making adequate decisions on how to Repair and reconstruct Nerves. The technique of peripheral Nerve Repair includes four important steps (preparation of Nerve end, approximation, coaptation and maintenance). Nerves are usually Repaired primarily with sutures applied in the different tissue components, but various tubes are available. Nerve grafts and Nerve transfers are alternatives when the injury induces a Nerve defect. Timing of Nerve Repair is essential. An early Repair is preferable since it is advantageous for neurobiological reasons. Postoperative rehabilitation, utilising the patients' own coping strategies, with evaluation of outcome are additional important steps in treatment of peripheral Nerve injuries. in the rehabilitation phase adequate handling of pain, allodynia and cold intolerance are emphasised.
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expression of atf3 and axonal outgrowth are impaired after delayed Nerve Repair
BMC Neuroscience, 2008Co-Authors: Harukazu Saito, Lars B DahlinAbstract:A delay in surgical Nerve Repair results in impaired Nerve function in humans, but mechanisms behind the weakened Nerve regeneration are not known. Activating transcription factor 3 (ATF3) increases the intrinsic growth state of injured neurons early after injury, but the role of long-term changes and their relation to axonal outgrowth after a delayed Nerve Repair are not well understood. ATF3 expression was examined by immunohistochemistry in motor and sensory neurons and in Schwann cells in rat sciatic Nerve and related to axonal outgrowth after transection and delayed Nerve Repair (Repair 0, 30, 90 or 180 days post-injury). Expression of the neuronal cell adhesion molecule (NCAM), which is expressed in non-myelinating Schwann cells, was also examined. The number of neurons and Schwann cells expressing ATF3 declined and the length of axonal outgrowth was impaired if the Repair was delayed. The decline was more rapid in motor neurons than in sensory neurons and Schwann cells. Regeneration distances over time correlated to number of ATF3 stained neurons and Schwann cells. Many neurofilament stained axons grew along ATF3 stained Schwann cells. If Nerve Repair was delayed the majority of Schwann cells in the distal Nerve segment stained for NCAM. Delayed Nerve Repair impairs Nerve regeneration and length of axonal outgrowth correlates to ATF3 expression in both neurons and Schwann cells. Mainly non-myelinating Schwann cells (NCAM stained) are present in distal Nerve segments after delayed Nerve Repair. These data provide a neurobiological basis for the poor outcomes associated with delayed Nerve Repair. Nerve trunks should, if possible, be promptly Repaired.
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Nerve Repair: Correlation of Restitution of Functional Sensibility with Specific Cognitive Capacities
Journal of Hand Surgery (European Volume), 1994Co-Authors: Birgitta Rosen, Goran Lundborg, Lars B Dahlin, Jan Holmberg, B. KarlsonAbstract:Abstract To test the hypothesis that cognitive capacity is correlated with the outcome of functional sensibility after Nerve Repair, 19 patients were evaluated 2 to 5 years after median or ulnar Nerve Repair at the distal forearm level. The sensory evaluation included tests for functional sensibility as well as assessments addressing perception thresholds for touch/pressure and vibration. Psychometric tests for cognitive capacity were also carried out. Multiple regression analysis, correcting for the effect of age and the ability to perceive touch/vibration, was used to investigate the relationship between functional sensibility and cognitive capacity, and to determine which of the tested central nervous factors had the greatest influence on the outcome of recovery of functional sensibility. On a ranking list of such factors verbal learning and visuo-spatial logic capacity were the most important ones, indicating significant correlations with functional sensibility. It is concluded that cognitive capacity factors may play an important role for the functional outcome following Nerve Repair and that variations in such factors may help to explain the variability in the outcome of Nerve Repair.
Kevin C Chung - One of the best experts on this subject based on the ideXlab platform.
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a systematic review of Nerve transfer and Nerve Repair for the treatment of adult upper brachial plexus injury
Neurosurgery, 2012Co-Authors: Lynda J S Yang, Kate W C Chang, Kevin C ChungAbstract:Abstract Nerve reconstruction for upper brachial plexus injury consists of Nerve Repair and/or transfer. Current literature lacks evidence supporting a preferred surgical treatment for adults with such injury involving shoulder and elbow function. We systematically reviewed the literature published from January 1990 to February 2011 using multiple databases to search the following: brachial plexus and graft, Repair, reconstruction, Nerve transfer, neurotization. Of 1360 articles initially identified, 33 were included in analysis, with 23 Nerve transfer (399 patients), 6 Nerve Repair (99 patients), and 4 Nerve transfer + proximal Repair (117 patients) citations (mean preoperative interval, 6 ± 1.9 months). For shoulder abduction, no significant difference was found in the rates ratio (comparative probabilities of event occurrence) among the 3 methods to achieve a Medical Research Council (MRC) scale score of 3 or higher or a score of 4 or higher. For elbow flexion, the rates ratio for Nerve transfer vs Nerve Repair to achieve an MRC scale score of 3 was 1.46 (P = .03); for Nerve transfer vs Nerve transfer + proximal Repair to achieve an MRC scale score of 3 was 1.45 (P = .02) and an MRC scale score of 4 was 1.47 (P = .05). Therefore, for elbow flexion recovery, Nerve transfer is somewhat more effective than Nerve Repair; however, no particular reconstruction strategy was found to be superior to recover shoulder abduction. When considering Nerve reconstruction strategies, our findings do not support the sole use of Nerve transfer in upper brachial plexus injury without operative exploration to provide a clear understanding of the pathoanatomy. Supraclavicular brachial plexus exploration plays an important role in developing individual surgical strategies, and Nerve Repair (when donor stumps are available) should remain the standard for treatment of upper brachial plexus injury except in isolated cases solely lacking elbow flexion.
Goran Lundborg - One of the best experts on this subject based on the ideXlab platform.
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hand function after Nerve Repair
Acta Physiologica, 2007Co-Authors: Goran Lundborg, Birgitta RosenAbstract:Treatment of injuries to major Nerve trunks in the hand and upper extremity remains a major and challenging reconstructive problem. Such injuries may cause long-lasting disabilities in terms of lost fine sensory and motor functions. Nowadays there is no surgical Repair technique that can ensure recovery of tactile discrimination in the hand of an adult patient following Nerve Repair while very young individuals usually regain a complete recovery of functional sensibility. Post-traumatic Nerve regeneration is a complex biological process where the outcome depends on multiple biological and environmental factors such as survival of Nerve cells, axonal regeneration rate, extent of axonal misdirection, type of injury, type of Nerve, level of the lesion, age of the patient and compliance to training. A major problem is the cortical functional reorganization of hand representation which occurs as a result of axonal misdirection. Although protective sensibility usually occurs following Nerve Repair, tactile discriminative functions seldom recover - a direct result of cortical remapping. Sensory re-education programmes are routinely applied to facilitate understanding of the new sensory patterns provided by the hand. New trends in hand rehabilitation focus on modulation of central nervous processes rather than peripheral factors. Principles are being evolved to maintain the cortical hand representation by using the brain capacity for visuo-tactile and audio-tactile interaction for the initial phase following Nerve injury and Repair (phase 1). After the start of the re-innervation of the hand (phase 2), selective de-afferentation, such as cutaneous anaesthesia of the forearm of the injured hand, allows expansion of the Nerve-injured cortical hand representation, thereby enhancing the effects of sensory relearning. Recent data support the view that training protocols specifically addressing the relearning process substantially increase the possibilities for improved functional outcome after Nerve Repair.
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sensory relearning after Nerve Repair
The Lancet, 2001Co-Authors: Goran Lundborg, Birgitta RosenAbstract:Summary One of the challenges in reconstructive surgery is to ensure hand sensibility is regained after median Nerve Repair. We assessed tactile gnosis in 54 patients (mean age 32 [range 4–72] years) after Repair of transected median or ulnar Nerves at the wrist level. We found that there is a well-defined critical period for sensory relearning after Nerve Repair. There is an optimum capacity below age 5–10 years followed by a rapid decline, which levels out after puberty. The curve correlates with previously published data on critical periods for language acquisition among immigrants. Recovery of functional sensibility after Nerve Repair is based on a learning process and in many ways is analogous to learning a second language.
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a model instrument for the documentation of outcome after Nerve Repair
Journal of Hand Surgery (European Volume), 2000Co-Authors: Birgitta Rosen, Goran LundborgAbstract:Abstract We present a new model for documentation and quantification of the functional outcome after Nerve Repair at the wrist or distal forearm level and a protocol that includes a numerical scoring system. The model, presented here along with validation and reliability test results, supports our hypothesis that the summarized test results reflecting specific functional limitations correlates well with the patient's opinion of the impact of the Nerve injury on activities of daily living. Seventy patients with Nerve Repair were examined using the protocol. Analysis included 3 factors: sensory domain (sensory innervation, tactile gnosis, and finger dexterity), motor domain (motor innervation and grip strength), and pain/discomfort domain (hyperaesthesia and cold intolerance). The analysis explained 73% of the variances of the variables and the variables had a logical distribution between the factors. Analysis of internal consistency demonstrated good homogeneity. A calculated total score correlated strongly with the patients' global estimation of the impact of the injury on activities of daily living and the summary of sensory and pain/discomfort domains correlated significantly with the Medical Research Council S0–S4 scale. The presented model represents a useful new tool for evaluation of the functional outcome after Nerve injury and Repair. (J Hand Surg 2000;25A:535–543. Copyright © 2000 by the American Society for Surgery of the Hand.)
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Nerve Repair: Correlation of Restitution of Functional Sensibility with Specific Cognitive Capacities
Journal of Hand Surgery (European Volume), 1994Co-Authors: Birgitta Rosen, Goran Lundborg, Lars B Dahlin, Jan Holmberg, B. KarlsonAbstract:Abstract To test the hypothesis that cognitive capacity is correlated with the outcome of functional sensibility after Nerve Repair, 19 patients were evaluated 2 to 5 years after median or ulnar Nerve Repair at the distal forearm level. The sensory evaluation included tests for functional sensibility as well as assessments addressing perception thresholds for touch/pressure and vibration. Psychometric tests for cognitive capacity were also carried out. Multiple regression analysis, correcting for the effect of age and the ability to perceive touch/vibration, was used to investigate the relationship between functional sensibility and cognitive capacity, and to determine which of the tested central nervous factors had the greatest influence on the outcome of recovery of functional sensibility. On a ranking list of such factors verbal learning and visuo-spatial logic capacity were the most important ones, indicating significant correlations with functional sensibility. It is concluded that cognitive capacity factors may play an important role for the functional outcome following Nerve Repair and that variations in such factors may help to explain the variability in the outcome of Nerve Repair.