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Biomedical subjects

Jack Besjakov

Publications and source records attributed to Jack Besjakov.

At least 19 recordsLinked to original sources
PubMed2006

Vertebral fractures in late adolescence: a 27 to 47-year follow-up.

The long-term outcome of thoracic and lumbar fractures in late adolescence is sparsely described and it is unclear whether a fractured vertebral body in these years, as in young children, can be resituated in height. The purpose of this study was to in late adolescence determine the incidence, the long-term outcome and the modelling capacity in fractures of the thoracic and lumbar region. The incidence of vertebral fractures 1950-1971 in individuals aged 16-18 years was through the radiological archives evaluated in a city cohort of 228,878 citizens, of whom 13,893 were aged 16-18. A follow-up, 27-47 years after the injury, including subjective, objective and radiological evaluation was conducted in 18 boys and 5 girls. Twenty-nine boys and 11 girls were registered with a thoracic or lumbar vertebral fracture during the study period conferring an annual incidence of 0.14 per thousand. Of the 23 individuals that attended the follow-up, 14 had one-column compression fractures, one a Denis type A, six a Denis type B, one a Denis type D and one a Chance fracture. At injury, one had a partial paresis in one leg and one developed a transient paraparesis during the first week. All were treated non-operatively. At follow-up, 18 individuals had no complaints while 5 had occasional back pain, 20 were classified as Frankel E and 3 as Frankel D. The radiographic ratio of anterior height to posterior height of the fractured vertebral body was unchanged during the study period. Thoracic and lumbar vertebral fractures in late adolescence with no or minor neurological deficits have a predominantly favourable long-term outcome, even if no modelling capacity of the fractured vertebral body remains in late adolescence.

Adolescent↗
PubMed2006

A school curriculum-based exercise program increases bone mineral accrual and bone size in prepubertal girls: two-year data from the pediatric osteoporosis prevention (POP) study.

UNLABELLED: This 2-year prospective controlled exercise intervention trial in 99 girls at Tanner stage 1, evaluating a school curriculum-based training program on a population-based level, showed that the annual gain in BMC, aBMD, and bone size was greater in the intervention group than in the controls. INTRODUCTION: Most exercise intervention studies in children, evaluating the accrual of BMD, include volunteers and use specifically designed osteogenic exercise programs. The aim of this study was to evaluate a 2-year general school-based exercise intervention program in a population-based cohort of girls at Tanner stage 1. MATERIALS AND METHODS: Forty-nine girls 7-9 years of age in grades 1 and 2 in one school were included in a school curriculum-based exercise intervention program of general physical activity for 40 minutes per school day (200 minutes/week). Fifty healthy age-matched girls in three neighboring schools, assigned to the general Swedish school curriculum of physical activity (60 minutes/week), served as controls. All girls were premenarchal, remaining in Tanner stage 1 during the study. BMC (g) and areal BMD (aBMD; g/cm2) were measured with DXA of the total body (TB), the lumbar spine (L2-L4 vertebrae), the third lumbar vertebra (L3), the femoral neck (FN), and the leg. Volumetric BMD (vBMD; g/cm3) and bone size were calculated at L3 and FN. Total lean body mass and total fat mass were estimated from the total body scan. Height and weight were also registered. Baseline measurements were performed before the intervention was initiated. Follow-up was done after 2 years. RESULTS: No differences between the groups were found at baseline in age, anthropometrics, or bone parameters. The annual gain in BMC was greater in the intervention group than in the controls: L2-L4, mean 3.8 percentage points (p = 0.007); L3 vertebra, mean 7.2 percentage points (p < 0.001); legs, mean 3.0 percentage points (p = 0.07). The intervention group had a greater annual gain in aBMD: total body, mean 0.6 percentage points (p = 0.006), L2-L4, mean 1.2 percentage points (p = 0.02), L3 vertebra, mean 1.6 percentage points (p = 0.006); legs, mean 1.2 percentage points (p = 0.007). There was also a greater mean annual gain in bone size in the L3 vertebra (mean 1.8 percentage points; p < 0.001) and in the FN (mean 0.3 percentage points; p = 0.02). CONCLUSIONS: A general school-based exercise program for 2 years for 7- to 9-year-old girls (baseline) enhances the accrual of BMC and BMD and increases bone size.

Bone and Bones↗
PubMed2006

Primary nonoperative treatment of moderately displaced two-part fractures of the radial head.

BACKGROUND: Moderately displaced two-fragment fractures of the radial head have been treated predominantly nonoperatively. Recently, however, open reduction and internal fixation has gradually gained interest, without clear evidence that initial nonoperative treatment leads to an unfavorable outcome. As a consequence, the purpose of the present study was to evaluate the long-term outcome after the initial nonoperative treatment of this type of fracture. METHODS: Fifteen men and thirty-four women, with a mean age of forty-nine years at the time of the injury, were included in the study. All patients initially had been managed nonoperatively for a two-fragment fracture of the radial head that was displaced 2 to 5 mm and that included >/=30% of the joint surface (a Mason type-IIa fracture). Early mobilization had been used for twenty-seven patients, and cast immobilization for a mean of two weeks (range, one to four weeks) had been used for twenty-two. All patients were reevaluated with a questionnaire after a mean of nineteen years, and thirty-four also had a clinical and a radiographic evaluation. Six patients had had a delayed radial head excision because of an unsatisfactory primary outcome. RESULTS: Forty of the forty-nine patients had no subjective complaints, eight were slightly impaired as the result of occasional elbow pain, and one had daily pain. Flexion was slightly impaired in the injured elbows as compared with the uninjured elbows (137 degrees +/- 8 degrees compared with 139 degrees +/- 7 degrees ), as was extension (-3 degrees +/- 7 degrees compared with 1 degrees +/- 5 degrees ) and supination (86 degrees +/- 7 degrees compared with 88 degrees +/- 4 degrees ) (p < 0.05 for all comparisons). The prevalence of degenerative changes on radiographs was higher for the injured elbows than for the uninjured elbows (82% [twenty-eight of thirty-four] compared with 21% [seven of thirty-four]; p < 0.01). CONCLUSIONS: The initial nonoperative treatment of Mason type-IIa fractures of the radial head that are displaced by 2 to 5 mm is associated with a predominantly favorable outcome, especially if a delayed radial head excision is performed in the few cases in which the early outcome is unsatisfactory. LEVEL OF EVIDENCE: Therapeutic Level IV.

Adolescent↗
PubMed2005

A glomus tumour: classic signs without magnetic resonance imaging findings.

A-36-year-old man presented with classic symptoms of a glomus tumour in the right index finger that failed to show on either ultrasound or high resolution magnetic resonance imaging (MRI). The radial finger pulp was explored despite the radiological findings and a glomus tumour 2 mm in size was excised. At follow-up the patient was pain-free. We conclude that exploration of an affected fingertip should be considered when there is a history of suspected glomus tumour even if MRI shows no sign of disease.

Adult↗
PubMed2005

Tibio-talocalcaneal arthrodesis as a primary procedure using a retrograde intramedullary nail: a retrospective study of 26 patients with rheumatoid arthritis.

BACKGROUND: Arthrodesis of the ankle joint using screws or external fixation is often a demanding procedure, notably in patients with rheumatoid arthritis. We investigated whether tibio-talocalcaneal arthrodesis with the use of an intramedullary nail is a safe and simple procedure. PATIENTS AND METHODS: We retrospectively reviewed 25 ankles (25 patients) at median 3 (1-7) years after tibio-talocalcaneal arthrodesis because of rheumatoid arthritis. All had been operated on by retrograde insertion of a retrograde nail. 5 types of nail had been used. Complications, functional outcome scores, and patient satisfaction were determined and the radiographs evaluated for healing. RESULTS: All but 1 ankle had a radiographically healed arthrodesis. We recorded 3 deep infections, all healed--in 2 cases after extraction of the nail--and the arthrodesis healed in all 3 patients. The average functional scores at follow-up were high, considering that the patients suffered from rheumatoid arthritis. 23 patients were satisfied with the outcome. We found a correlation between the functional scores and the general activity of the disease expressed as a Health Assessment Questionnaire score. INTERPRETATION: In patients with rheumatoid arthritis, tibio-talocalcaneal arthrodesis with a retrograde intra-medullary nail results in a high rate of healing, a high rate of patient satisfaction, and relatively few complications.

Adult↗
PubMed2005

Ankle arthrodesis by compression screws in rheumatoid arthritis: primary nonunion in 9/35 patients.

INTRODUCTION: Today, percutaneous or open arthrodesis of the ankle, using one or several screws for fixation, is a common method for treatment of the rheumatic ankle. However, there is very little information in the literature on the reliability of the method. METHODS: We performed a retrospective radiographic and clinical study on 35 ankles of 35 patients. Function was evaluated using the Mazur and AOFAS scores. For evaluation of activity of the rheumatic disease, we used the HAQ score. RESULTS: 31 ankles had healed--26 at the first attempt and 5 after repeat arthrodesis. There was no difference between 13 cases operated on percutaneously and 22 cases operated on with open technique with respect to radiographic healing. Mean AOFAS total score was 56 of possible 86 points. The AOFAS total score correlated with the severity of the rheumatic disease. 20 patients were satisfied with the result, 12 were somewhat satisfied and 3 patients were dissatisfied although the ankle in 2 of these 3 patients had fused. INTERPRETATION: The use of compression screws for fusion of the rheumatic ankle does not appear to give acceptable results regarding healing and function.

Adult↗
PubMed2005

Inter-observer variation in masked and unmasked images for quality evaluation of clinical radiographs.

PURPOSE: To investigate the influence of masking on the inter-observer variation in image quality evaluation of clinical radiographs of chest and lumbar spine. BACKGROUND: Inter-observer variation is a big problem in image quality evaluation since this variation is often much bigger than the variation in image quality between, for example, two radiographic systems. In this study, we have evaluated the effect of masking on the inter-observer variation. The idea of the masking was to force every observer to view exactly the same part of the image and to avoid the effect of the overall 'first impression' of the image. A discussion with a group of European expert radiologists before the study indicated that masking might be a good way to reduce the inter-observer variation. METHODS: Five chest and five lumbar spine radiographs were collected together with detailed information regarding exposure conditions. The radiographs were digitised with a high-performance scanner and five different manipulations were performed, simulating five different exposure conditions. The contrast, noise and spatial resolution were manipulated by this method. The images were printed onto the film and the individual masks were produced for each film, showing only the parts of the images that were necessary for the image quality evaluation. The quality of the images was evaluated on ordinary viewing boxes by a large group of experienced radiologists. The images were examined with and without the masks with a set of image criteria (if fulfilled, 1 point; and not fulfilled, 0 point), and the mean score was calculated for each simulated exposure condition. RESULTS: The results of this study indicate that-contrary to what was supposed-the inter-observer variation increased when the images were masked. In some cases, especially for chest, this increase was statistically significant. CONCLUSIONS: Based on the results of this study, image masking in studies of fulfilment of image criteria cannot be recommended.

Computers↗
PubMed2005

Evaluation of image quality of lumbar spine images: a comparison between FFE and VGA.

PURPOSE: The aim of the present study is to compare two different methods for evaluation of the quality of clinical X-ray images. METHODS: Based on fifteen lumbar spine radiographs, two new sets of images were created. A hybrid image set was created by adding two distributions of artificial lesions to each original image. The image quality parameters spatial resolution and noise were manipulated and a total of 210 hybrid images were created. A set of 105 disease-free images was created by applying the same combinations of spatial resolution and noise to the original images. The hybrid images were evaluated with the free-response forced error experiment (FFE) and the normal images with visual grading analysis (VGA) by nine experienced radiologists. RESULTS: In the VGA study, images with low noise were preferred over images with higher noise levels. The alteration of the MTF had a limited influence on the VGA score. For the FFE study, the visibility of the lesions was independent of the sharpness and the noise level. No correlation was found between the two image quality measures. CONCLUSIONS: FFE is a precise method for evaluation of image quality, but the results are only valid for the type of lesion used in the study, whereas VGA is a more general method for clinical image quality assessment. The results of the FFE study indicate that there might be a potential to lower the dose levels in lumbar spine radiography without losing important diagnostic information.

Calibration↗
PubMed2005

Cemented tibial component fixation performs better than cementless fixation: a randomized radiostereometric study comparing porous-coated, hydroxyapatite-coated and cemented tibial components over 5 years.

BACKGROUND: The question whether the tibial component of a total knee arthroplasty should be fixed to bone with or without bone cement has not yet been definitely answered. We studied movements between the tibial component and bone by radiostereometry (RSA) in total knee replacement (TKR) for 3 different types of fixation: cemented fixation (C-F), uncemented porous fixation (UC-F) and uncemented porous hydroxyapatite fixation (UCHA-F). PATIENTS: 116 patients with osteoarthrosis, who had 146 TKRs, were included in 2 randomized series. The first series included 86 unilateral TKRs stratified into 1 of the 3 types of fixation. The second series included 30 patients who had simultaneous bilateral TKR surgery, and who were stratified into 3 subgroups of pairwise comparisons of the 3 types of fixation. RESULTS: After 5 years 2 knees had been revised, neither of which were due to loosening. 1 UCHA-F knee in the unilateral series showed a large and continuous migration and a poor clinical result, and is a pending failure. The C-F knees rotated and migrated less than UC-F and UCHA-F knees over 5 years. UCHA-F migrated less than UC-F after 1 year. INTERPRETATION: Cementing of the tibial component offers more stable bone-implant contact for 5 years compared to uncemented fixation. When using uncemented components, however, there is evidence that augmenting a porous surface with hydroxyapatite may mean less motion between implant and bone after the initial postoperative year.

Aged↗
PubMed2004

Factor V Leiden and the prothrombin 20210A gene mutation and osteonecrosis of the knee.

INTRODUCTION: The pathogenesis behind osteonecrosis of the knee is still unknown. Circulatory impairment of the bone secondary to thrombosis in the microcirculation has been suggested as a mechanism. The purpose of this study was to examine the association between osteonecrosis of the knee and abnormalities in the thrombotic pathway in the form of factor V Leiden and the prothrombin 20210A gene mutation. MATERIALS AND METHODS: Thirty-eight consecutive patients (13 men and 25 women) with osteonecrosis of the knee without a history of knee trauma or surgery to the knee were enrolled in this study. Assays for the detection of factor V Leiden and the prothrombin 20210A gene mutation were performed, and the results were compared with those from 282 healthy volunteers. RESULTS: Six patients were diagnosed with secondary osteonecrosis, four corticosteroid-induced and two alcohol-induced. In 32 patients, no aetiological factor was found, and these patients were diagnosed with primary osteonecrosis of the knee. Twelve patients had 14 gene mutations, 11 factor V Leiden and 3 prothrombin 20210A gene mutations. Factor V Leiden and the prothrombin 20210A gene mutation occurred significantly (p=0.006) more frequently in patients with osteonecrosis than in a population of 282 healthy volunteers (odds ratio 3.1, 95%CI 1.4-6.6). CONCLUSION: The results of this study suggest that coagulation abnormalities in the form of factor V Leiden and the prothrombin 20210A gene mutation might play a role in osteonecrosis of the knee.

Adult↗
PubMed2004

Adding sodium and calcium ions to the contrast medium iodixanol reduced the risk of ventricular fibrillation during perfusion of the left coronary artery in pigs: effects of electrolytes, viscosity, and chemotoxicity of an isotonic perfusate.

RATIONAL AND OBJECTIVES: The effects of electrolytes, viscosity, and chemotoxicity of a plasma-isotonic iodine contrast medium iodixanol were compared with regard to its propensity to cause ventricular fibrillation (VF). MATERIALS AND METHODS: The left coronary artery of pigs was perfused with five isotonic solutions: iodixanol 320 mg I/mL with 19 mmol/L NaCl + 0.3 mmol/L CaCl2, Iod 320+Mann (iodixanol 320 mg I/mL + 50 mmol/L mannitol), Mann+Na/Ca (240 mmol/L mannitol with 19 mmol/L NaCl + 0.3 mmol/L CaCl2), Mann (275 mmol/L mannitol) and Ringer. The first two solutions have at 37 degrees C a viscosity of approximately 13 mPa x s while the others have a viscosity < 1 mPa x s. In eight pigs, each test solution was injected twice into the left coronary artery in random order for 10 seconds (injection volume, 20 mL). In 15 pigs, each of the solutions was injected in random order for 11-40 seconds through the end-hole of a wedged 5F balloon catheter in left coronary artery. Injection rate was 0.5 mL/sec until VF occurred. If VF occurred, injection was stopped and the heart was defibrillated. If VF did not occur, the perfusion period was 40 seconds. RESULTS: The 10-second perfusions caused no VF. The 40-second perfusions with iodixanol 320 mg I/mL with 19 mmol/L NaCl + 0.3 mmol/L CaCl2 or Ringer caused no VF (0%). Iod 320+Mann caused nine VF (60%) after 35 +/- 4 seconds (SEM). Mann+Na/Ca caused 14 VF (93%) after 30 +/- 2 seconds. Mann caused 15 VF (100%) after 24 +/- 2 seconds. Iodixanol 320 mg I/mL with 19 mmol/L NaCl + 0.3 mmol/L CaCl2 and Ringer caused fewer VF than all other solutions (P < .05-.001). Iod 320+Mann caused fewer VF than Mann (P < .05). Iod 320+Mann caused VF later than Mann+Na/Ca or Mann (P < .02 and P < .01). Mann+Na/Ca caused VF later than Mann (P < .05). CONCLUSION: The results fit with a concept that VF starts when the electrolyte composition of the interstitial fluid in the myocardium is sufficiently nonphysiologic. The more physiologic the electrolyte composition of the perfusion fluid, and the higher its viscosity, the slower the composition of the interstitial fluid will be changed, and VF will occur later (or not at all).

Animals↗
PubMed2004

Uncomplicated Mason type-II and III fractures of the radial head and neck in adults. A long-term follow-up study.

BACKGROUND: The purpose of this study was to evaluate the incidence and the long-term results of closed uncomplicated Mason type-II and III fractures in a defined population of adults. METHODS: Seventy women and thirty men who were a mean of forty-seven years old when they sustained a fracture of the radial head or neck (a Mason type-II fracture in seventy-six patients and a Mason type-III fracture in twenty-four) were reexamined after a mean of nineteen years. Radiographic signs of degenerative changes of the elbow were recorded. The fracture had been treated with an elastic bandage or a collar and cuff sling with mobilization for forty-four individuals, with cast immobilization for thirty-four, with resection of the radial head in nineteen, with open reduction of the radial head in two, and with a collateral ligament repair in one. Secondary excision of the radial head was performed because of residual pain in nine patients, and a neurolysis of the ulnar nerve was performed in one patient. RESULTS: Seventy-seven individuals had no symptoms in the injured elbow at the time of follow-up, twenty-one had occasional pain, and two had daily pain. The injured elbows had a slight flexion deficit compared with the uninjured elbows (mean and standard deviation, 138 degrees +/- 8 degrees compared with 140 degrees +/- 7 degrees ) as well as a small extension deficit (mean and standard deviation, -4 degrees +/- 8 degrees compared with -1 degrees +/- 6 degrees ) (p < 0.001 for both). The prevalence of degenerative changes was higher in the injured elbows than in the uninjured ones (76% compared with 16%, p < 0.001). CONCLUSIONS: The results following uncomplicated Mason type-II and III fractures are predominantly favorable. A secondary radial head resection is usually effective for patients with an unfavorable outcome (predominantly long-standing pain). LEVELS OF EVIDENCE: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.

Activities of Daily Living↗
PubMed2004

Fractures of the radial head and neck treated with radial head excision.

BACKGROUND: The reported long-term outcomes of the treatment of radial head and neck fractures with excision of the radial head have been mixed. The purpose of the present study was to evaluate the long-term outcomes of primary or delayed radial head excision for the treatment of these fractures. METHODS: Sixty-one individuals (mean age, forty-four years) with thirty-nine Mason type-II, ten Mason type-III, and twelve Mason type-IV fractures were evaluated subjectively, objectively, and radiographically at a mean of eighteen years (range, eleven to thirty-three years) after treatment. Forty-three fractures were treated with primary radial head excision, and the remaining eighteen were treated with delayed radial head excision at a median of five months (range, one to 238 months) after the injury. RESULTS: At the time of follow-up, twenty-eight individuals had no symptoms, twenty-seven had occasional elbow pain, and six had daily pain. Four individuals with daily pain had had a Mason type-IV fracture. The range of motion of the formerly injured upper extremities was slightly less than that of the uninjured upper extremities in terms of flexion (139 degrees +/- 11 degrees compared with 142 degrees +/- 8 degrees ), extension (-7 degrees +/- 12 degrees compared with -1 degrees +/- 6 degrees ), and supination (77 degrees +/- 20 degrees compared with 85 degrees +/- 10 degrees ) (all p < 0.01). A higher percentage of formerly injured elbows than uninjured elbows had cysts, sclerosis, and osteophytes (73% compared with 7%; p < 0.001), but none had a reduced joint space. No differences were found between the outcomes for individuals treated with a primary radial head excision and those for individuals treated with a delayed excision. CONCLUSIONS: Following a displaced radial head or neck fracture, excision of the radial head often leads to a good or fair result. We found no differences in outcome between primary and delayed radial head excisions following a Mason type-II, III, or IV fracture. The outcomes are associated with the type of fracture, with Mason type-IV fractures having the worst results, rather than with the timing of the radial head excision (primary or delayed).

Adolescent↗
PubMed2003

A modeling capacity of vertebral fractures exists during growth: an up-to-47-year follow-up.

STUDY DESIGN: The study is an observational cohort study. OBJECTIVES: To determine the incidence and the long-term outcome of thoracic or lumbar vertebral fractures in children. SUMMARY OF BACKGROUND DATA: The incidence of vertebral fractures in children is described as rare and the outcome as favorable. However, no studies evaluate the clinical and radiographic long-term outcome and if a fractured vertebra could be rebuilt during growth. METHOD: The incidence of vertebral fractures in children was evaluated through the radiographic archives. Twelve boys and 12 girls, aged 7-16 when sustaining the fracture, 21 one-column compression fractures and 3 burst fractures Denis type B, all without neurologic deficits, attended the follow-up. Primary treatment consisted of immediate mobilization without brace. Clinical and radiographic examinations were performed 27-47 years after the injury. RESULTS: The annual incidence of thoracic and lumbar vertebral body fractures in individuals below age 16 was 0.07%. Twenty-one individuals had, at follow-up, no subjective complaints, 3 had occasional back pain (Oswestry Scores 8, 22, and 26), 23 were classified as Frankel E, and 1 as Frankel D. The radiographic ratio anterior height/posterior height of the fractured vertebral body increased from 0.75 after injury to 0.87 at follow-up (P < 0.001). The posttraumatic kyphosis in the fractured region decreased in 8 individuals (33%), all aged 13 or less at fracture. No increased disc degeneration was observed. CONCLUSION: Thoracolumbar vertebral fractures without neurologic deficits, sustained during growth, have a favorable long-term outcome. A modeling capacity, reducing the fracture deformity, exists at least in the youngest patients.

Adolescent↗
PubMed2003

Fracture of the radial head and neck of Mason types II and III during growth: a 14-25 year follow-up.

Twenty-four individuals, who were 16 years of age or younger when they sustained a fracture of the radial head or neck, were examined at a mean of 19 years (range 14-25 years) after injury. The 12 girls and 12 boys were a mean age of 11 years (range 5-16 years) when the fracture was sustained. Two were excluded due to late resection of the radial head following persisting pain. The fractures, which were of Mason type II in 19 and type III in three cases, were treated by mobilization in eight cases, plaster in eight, open reduction and internal fixation in three and closed reduction and plaster in three. At the follow-up examination, 19 (86%) had no complaints, while three (14%) had occasional pain. Flexion was decreased in the formerly injured compared with the uninjured elbow (139 +/- 8 degrees versus 142+/-5 degrees; P<0.05). None had developed elbow osteoarthritis. Isolated, closed fracture of the radial head and neck during growth has a favourable, long-term outcome.

Adolescent↗
PubMed2002

Granular cell tumour of the ulnar nerve in a young adult.

Granular cell tumours in peripheral nerve trunks are extremely rare. We report a case of a granular cell tumour of the ulnar nerve just distal to the elbow in a 16-year-old man. The appearance of the intraneural tumour could not be differentiated by magnetic resonance imaging (MRI) from more common nerve tumours. At exploration it was impossible to excise the tumour radically. Microscopic examination showed a clearly benign tumour and no malignant transformation has been found at follow-up after three and a half years.

Adolescent↗