Clas Backman
Umeå University
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Publication
Featured researches published by Clas Backman.
British Journal of Sports Medicine | 2011
Gustav Andersson; Sture Forsgren; Alex Scott; James E. Gaida; Johanna Elgestad Stjernfeldt; Ronny Lorentzon; Håkan Alfredson; Clas Backman; Patrik Danielson
Objective To determine whether there are objective findings of tendinosis in a rabbit tendinopathy model on exercised and contralateral (non-exercised) Achilles tendons. Design Four groups of six New Zealand white rabbits per group were used. The animals of one (control) group were not subjected to exercise/stimulation. Interventions Animals were subjected to a protocol of electrical stimulation and passive flexion–extension of the right triceps surae muscle every second day for 1, 3 or 6 weeks. Main Outcome Measures Tenocyte number and vascular density were calculated. Morphological evaluations were also performed as well as in-situ hybridisation for vascular endothelial growth factor (VEGF) messenger RNA. Results There was a significant increase in the tenocyte number after 3 and 6 weeks of exercise, but not after 1 week, in comparison with the control group. This was seen in the Achilles tendons of both legs in experimental animals, including the unexercised limb. The pattern of vascularity showed an increase in the number of tendon blood vessels in rabbits that had exercised for 3 weeks or more, compared with those who had exercised for 1 week or not at all. VEGF-mRNA was detected in the investigated tissue, with the reactions being more clearly detected in the tendon tissue with tendinosis-like changes (6-week rabbits) than in the normal tendon tissue (control rabbits). Conclusions There were bilateral tendinosis-like changes in the Achilles tendons of rabbits in the current model after 3 weeks of training, suggesting that central neuronal mechanisms may be involved and that the contralateral side is not appropriate as a control.
Journal of Internal Medicine | 2008
Ole B. Suhr; Intissar Anan; Clas Backman; A Karlsson; Per Lindqvist; Stellan Mörner; Anders Waldenström
Objectives. Cardiomyopathy is a well known complication in familial amyloidotic polyneuropathy (FAP). Troponin T and B‐natriuretic peptide (BNP) have been shown to be excellent markers for heart complications in AL‐amyloidosis. The aim of the study was to investigate troponin T, troponin I and BNP as markers for myocardial damage and failure in FAP.
Journal of Hand Surgery (European Volume) | 1993
Clas Backman; Åke Nyström; Per Bjerle
Cold induced arterial vasospasm was studied in ten patients with single digit replantation, by measuring finger systolic pressure at different finger temperatures. Each patient was examined three times; within 2 weeks of surgery, after 1 year and after 3 years. The replantations were performed using long arterial and venous grafts. Cold-related vasospasm is established during the first year after trauma, and thereafter seems to be persistent. It is concluded that the subjective cold intolerance, which affects all patients after digital amputation regardless of whether replantation is performed or not, is partly due to vasospasm. It is less pronounced in patients without pathological vasospasm in the replanted digit. Cold intolerance is likely to decrease during the first 2 years after replantation, but not to disappear completely.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2003
Mikael Wiberg; Anita Hazari; Christina Ljungberg; Kurt Pettersson; Clas Backman; Erik Nordh; Olga Kwast-Rabben; Giorgio Terenghi
Despite fairly good return of motor function, patients who have amputated hands reimplanted demonstrate poor sensory recovery and severe cold intolerance, two variables that are difficult to quantify reliably. In this study we wanted to find out if there is a correlation between morphological findings of sensory and sympathetic reinnervation and clinical and neurophysiological variables. Skin was biopsied from the reimplanted and corresponding area in the normal hands of eight patients who had sustained a hand amputation and subsequent reimplantation. The sections were immunostained using markers for both sensory and sympathetic nerve fibres. Comparison between the reimplanted and normal sides in each individual showed a mean loss of sensory immunoreactive nerve fibres of 30%, and for sympathetic immunoreactivity the loss was 60%. There was measurable two-point discrimination in the injured hand only in patients below the age of 40 years, corresponding to the better recovery of mechanical thresholds evaluated neurophysiologically for this age group. These results confirm the extensive loss of sensory nerve fibres after nerve injury, probably correlated to loss of sensory neurons. We have also shown that it is possible to correlate the results of clinical and neurophysiological evaluation with morphological results of skin reinnervation specific to the repaired nerve, and so improve the possibility for the quantification of sensory recovery.
Journal of Brachial Plexus and Peripheral Nerve Injury | 2014
Lars B. Dahlin; Kristina Erichs; Charlotte Andersson; Catharina Thornqvist; Clas Backman; Henrik Düppe; Pelle G. Lindqvist; Marianne Forslund
Background Posterior dislocation of the shoulder in brachial plexus birth palsy during the first year of life is rare but the incidence increases with age. The aim was to calculate the incidence of these lesions in children below one year of age. Methods The incidence of brachial plexus birth lesion and occurrence of posterior shoulder dislocation was calculated based on a prospective follow up of all brachial plexus patients at an age below one in Malmö municipality, Sweden, 2000–2005. Results The incidence of brachial plexus birth palsy was 3.8/1000 living infants and year with a corresponding incidence of posterior shoulder dislocation (history, clinical examination and x-ray) during the first year of 0.28/1000 living infants and year, i.e. 7.3% of all brachial plexus birth palsies. Conclusion All children with a brachial plexus birth lesion (incidence 3.8‰) should be screened, above the assessment of neurological recovery, during the first year of life for posterior dislocation of the shoulder (incidence 0.28‰) since such a condition may occur in 7% of children with a brachial plexus birth lesion.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 2000
Kathrin Härén; Clas Backman; Mikael Wiberg
The aim of this study was to evaluate the efficacy of manual lymph drainage, as described by Vodder, in reducing oedema in the hand after a traumatic injury. During a period of 10 months in 1996-7, a total of 26 consecutive patients with a fracture of the distal radius that was treated by external fixation were included in the study. Patients were randomised into an experimental (n = 12) and a control group (n = 14). Treatment started 11 days after application of the external fixator. All patients had the same conventional treatment with exercises, movement, oedema control, and education. The experimental group was given 10 treatments of manual lymph drainage in addition. Oedema was measured four times with the volumeter, and the injured hand was always compared with the uninjured one. The first measurement was made three days after removal of the external fixation. The difference in hand volume showed that the experimental group had significantly less oedema in the injured hand. This result indicates that manual lymph drainage is a useful method for reducing post-traumatic oedema in the hand.The aim of this study was to evaluate the efficacy of manual lymph drainage, as described by Vodder, in reducing oedema in the hand after a traumatic injury. During a period of 10 months in 1996-7, a total of 26 consecutive patients with a fracture of the distal radius that was treated by external fixation were included in the study. Patients were randomised into an experimental (n = 12) and a control group (n = 14). Treatment started 11 days after application of the external fixator. All patients had the same conventional treatment with exercises, movement, oedema control, and education. The experimental group was given 10 treatments of manual lymph drainage in addition. Oedema was measured four times with the volumeter, and the injured hand was always compared with the uninjured one. The first measurement was made three days after removal of the external fixation. The difference in hand volume showed that the experimental group had significantly less oedema in the injured hand. This result indicates that manual lymph drainage is a useful method for reducing post-traumatic oedema in the hand.
Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 1995
Clas Backman; Åke Nyström; Christer Backman; Per Bjerle
Nineteen patients each of whom had had a single digit replanted were examined after replantation. The arterial reconstruction had been done with long grafts (n = 10) or short grafts or no graft (n = 9). The effect of local or whole body cooling on the replanted and uninjured opposite digits was monitored (9-46 months after the replantation), and the patients were given a questionnaire (9-95 months after replantation) designed to explore the development of their cold related symptoms in relation to time. All patients were troubled by cold intolerance, and improvement occurred in only 60% of the cases. Pathological (vasospastic) arterial reactions to cold measured as finger systolic pressure, were less common after replantation with long grafts. Perceived cold intolerance was significantly more pronounced in the group of patients (60%) who had evidence of cold induced arterial spasm in the replanted finger.
Journal of Internal Medicine | 1990
A. Kristoffersson; Clas Backman; K. Granqvist; J. Järhult
Abstract. Renal function was investigated immediately before and 1 year following parathyroidectomy in 19 patients with moderate hypercalcaemia. On both occasions, all patients underwent five different tests of glomerular and tubular function: plasma creatinine, creatinine clearance, 51Cr‐EDTA‐clearance, β2‐microglobulin excretion and the desmopressin test.
Journal of Brachial Plexus and Peripheral Nerve Injury | 2014
Kasim Abul-Kasim; Clas Backman; Anders Björkman; Lars B. Dahlin
Background As neurophysiologic tests may not reveal the extent of brachial plexus injury at the early stage, the role of early radiological work-up has become increasingly important. The aim of the study was to evaluate the concordance between the radiological and clinical findings with the intraoperative findings in adult patients with brachial plexus injuries. Methods Seven consecutive male patients (median age 33; range 15-61) with brachial plexus injuries, caused by motor cycle accidents in 5/7 patients, who underwent extensive radiological work-up with magnetic resonance imaging (MRI), computed tomography myelography (CT-M) or both were included in this retrospective study. A total of 34 spinal nerve roots were evaluated by neuroradiologists at two different occasions. The degree of agreement between the radiological findings of every individual nerve root and the intraoperative findings was estimated by calculation of kappa coefficient (К-value). Using the operative findings as a gold standard, the accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the clinical findings and the radiological findings were estimated. Results The diagnostic accuracy of radiological findings was 88% compared with 65% for the clinical findings. The concordance between the radiological findings and the intraoperative findings was substantial (К = 0.76) compared with only fair (К = 0.34) for the clinical findings. There were two false positive and two false negative radiological findings (sensitivity and PPV of 0.90; specificity and NPV of 0.87). Conclusions The advanced optimized radiological work-up used showed high reliability and substantial agreement with the intraoperative findings in adult patients with brachial plexus injury.
Journal of Plastic Surgery and Hand Surgery | 2012
Lars B. Dahlin; Marcus E. Cöster; Anders Björkman; Clas Backman
Abstract An injury to the axillary nerve from a shoulder trauma can easily be overlooked. Spontaneous functional recovery may occur, but occasionally reconstructive surgery is required. The time frame for nerve reconstruction procedures is from a neurobiological view crucial for a good functional outcome. This study presents a group of operatively and non-operatively treated young adults with axillary nerve injuries caused by motorcycle accidents, where the diagnosis was set late. Ten young men (median age at trauma 13 years, range 9–24) with an axillary nerve injury were diagnosed by examination of shoulder function and electromyography (EMG). The patients had either a nerve reconstruction procedure or were treated conservatively and their recovery was monitored. The axillary nerve was explored and reconstructed at a median of 8 months (range 1–22 months) after trauma in 8/10 patients. Two patients were treated non-operatively. In 4/8 cases, a reconstruction with sural nerve graft was performed and in 1/8 case only exploration of the nerve was made (minor neuroma). In 3/8 cases a radial nerve branch transfer to the axillary nerve was chosen as the procedure. The shoulder was mobilised after 3 weeks with physiotherapy and the patients were monitored regularly. Functional recovery was observed in 9/10 cases (median follow up 11 months, range 7–64) with EMG signs of reinnervation in seven patients. Axillary nerve function should not be overlooked in young patients with a minor shoulder trauma. Nerve reconstruction can successfully recreate function.