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K Jonsson

Publications and source records attributed to K Jonsson.

At least 19 recordsLinked to original sources

Kyphoplasty.

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Bone Cements↗

Repeatability of sonographic measurements in clubfeet.

PURPOSE: To assess the intra- and interobserver agreement of ultrasound assessment of clubfoot patho-anatomy in early childhood. MATERIAL AND METHODS: Seventeen clubfeet in 12 children were sequentially scanned by 2 examiners and repeat assessments were carried out independently. Three well-defined imaging planes were chosen to evaluate navicular displacement: the medial malleolus-navicular (MM-N) distance, soft tissue thickness, talar deformity and the calcaneo-cuboid (C-C) distance. Intra- and interobserver agreement was analysed using Cohen's kappa for the discrete variables and by Bland-Altman's graphic technique for measurements. RESULTS: Kappa values for intra-observer agreement were 0.82 for navicular displacement, 0.93 for "talar head pointing laterally", and 0.70 for medial deviation of the talar neck. The corresponding interobserver kappa values were 0.70, 0.68, and 0.36. The mean difference between the two observers for the MM-N distance was 0.42 +/- 3.0 mm and for the soft tissue thickness 0.35 +/- 2.0 mm; the C-C distance showed a mean interobserver distance of 0.0 +/- 2.8 mm. CONCLUSION: The imaging planes used to study the talo-navicular and calcaneo-cuboid relationships are reproducible and relatively easy to learn. Intra- and interobserver assessments were acceptable for MM-N distance, soft tissue thickness, navicular displacement and "talar head pointing laterally", but questionable for the C-C distance and medial deviation of the talar neck.

Clubfoot↗

Are digital images good enough? A comparative study of conventional film-screen vs digital radiographs on printed images of total hip replacement.

The aim of this study was to evaluate the inter- and intra-observer variability and to find differences in diagnostic safety between digital and analog technique in diagnostic zones around hip prostheses. In 80 patients who had had a total hip replacement (THR) for more than 2 years, a conventional image and a digital image were taken. Gruen's model of seven distinct regions of interest was used for evaluations. Five experienced radiologists observed the seven regions and noted in a protocol the following distances: stem-cement; cement-bone; and stem-bone. All images were printed on hard copies and were read twice. Weighted kappa, kappa(w), analyses were used. The two most frequently loosening regions, stem-cement region 1 and cement-bone region 7, were closely analyzed. In region 1 the five observers had an agreement of 86.75-97.92% between analog and digital images in stem-cement, which is a varied kappa(w) 0.29-0.71. For cement-bone region 7 an agreement of 87.21-90.45% was found, which is a varied kappa(w) of 0.48-0.58. All the kappa values differ significantly from nil. The result shows that digital technique is as good as analog radiographs for diagnosing possible loosening of hip prostheses.

Arthroplasty, Replacement, Hip↗

Scandinavian Sarcoma Group Osteosarcoma Study SSG VIII: prognostic factors for outcome and the role of replacement salvage chemotherapy for poor histological responders.

From 1990 to 1997, 113 eligible patients with classical osteosarcoma received neo-adjuvant chemotherapy consisting of high-dose methotrexate, cisplatin and doxorubicin. Good histological responders continued to receive the same therapy postoperatively, while poor responders received salvage therapy with an etoposide/ifosfamide combination. With a median follow-up of 83 months, the projected metastasis-free and overall survival rates at 5 years are 63 and 74%, respectively. Independent favourable prognostic factors for outcome were tumour volume < 190 ml, 24-h serum methotrexate > 4.5 microM and female gender. The etoposide/ifosfamide replacement combination did not improve outcome in the poor histological responders. In conclusion, this intensive multi-agent chemotherapy results in > 70% of patients with classical osteosarcoma surviving for 5 years. The data obtained from this non-randomised study do not support discontinuation and exchange of all drugs used preoperatively in histological poor responders. As observed in previous Scandinavian osteosarcoma studies, female gender appears to be a strong predictor of a favourable outcome.

Adolescent↗

Joint space width of the tibiofemoral and of the patellofemoral joint in chronic knee pain with or without radiographic osteoarthritis: a 2-year follow-up.

OBJECTIVES: To assess the interval change of the minimal joint space width (MJS) in radiographs of the tibiofemoral (TF) joint and of the patellofemoral (PF) joint with a 2-year follow-up in middle-aged people with longstanding knee pain with or without radiographic osteoarthritis (OA) and to study the precision of the MJS measurements. DESIGN: In the format of a prospective study of early OA the signal knee in 55 people, 28 men and 27 women (aged 41-57 years, median 50), with chronic knee pain at inclusion was examined with a 2-year interval (median 25 months, range 21-30). The MJS of the TF joint was measured using a flexed PA view in weightbearing and the MJS of the PF joint using an axial view in standing. RESULTS: The MJS of the TF joint decreased medially by 0.056+/-0.44mm (n.s.) and increased laterally by 0.080+/-0.51mm (n.s.) during the time of observation. In knees with an MJS medially that was less or the same as compared with the lateral compartment, the MJS decreased by 0.14+/-0.38mm (p=0.038) and in a subgroup of these knees, without osteophytes, the MJS decreased by 0.14+/-0.27mm (p=0.018). The MJS of the PF joint decreased by 0.019mm (n.s.) during the time of observation. The coefficient of variation for intra- and interobserver MJS measurements of the TF joint was 1.0 and 1.1% medially and 2.3 and 2.7% laterally, and for measurement error 6.9% medially and 4.8% laterally, respectively. The coefficient of variation for intra- and interobserver MJS measurements of the PF joint was 8.1 and 5.8% medially and 7.5 and 10.1% laterally and for the measurement error it was 8.1% medially and 8.5% laterally, respectively. CONCLUSIONS: A statistically significant reduction of the MJS was only demonstrated in the medial compartment of the TF joint in those individuals who had an MJS in this compartment which was less or the same as compared with the lateral compartment as well as in a subgroup of these knees without osteophytes. The radiographic examinations and the MJS measurements were reproducible.

Adult↗

Distribution of MR-detected cartilage defects of the patellofemoral joint in chronic knee pain.

OBJECTIVES: The aim of the study was to detect cartilage defects and determine the center of these defects in MR imaging of the patellofemoral joint (PFJ) in middle-aged people with chronic knee pain. DESIGN: In the format of a prospective study of early osteoarthritis (OA), this cross-sectional study of the signal knee (the most painful one at inclusion in the study in 1990) in 59 individuals, 30 women and 29 men (aged 41-58 years, mean 50 years) with chronic knee pain, with or without radiographically determined knee OA, was examined using MR imaging on a 1.0 T imager. Cartilage defects and the center of these defects in the PFJ were recorded. RESULTS: Cartilage defects were found more often in the patella (40 knees) than in the femoral trochlea (23 knees) (P<0.001) and were unevenly distributed in the patella (P<0.001), with most cartilage defects in the mid-patella. CONCLUSIONS: Since cartilage defects occur more commonly in the mid-patella, radiographs obtained with a knee flexion of approximately 45 degrees may be more accurate to show cartilage defects of early OA of the PFJ than views with another knee flexion.

Adult↗

Hip fracture patients have more vertebral deformities than subjects in population-based studies.

The prevalence of vertebral deformity, estimated in lateral spine radiographs (Th4-L4) using quantitative morphometry, in 64 men and 132 women with hip fractures was compared with the prevalence of vertebral deformity in individuals in two population-based studies. A vertebral deformity of a specific vertebra was defined as a 3, 4, or 5 SD reduction from the normal mean of any of three ratios describing that specific vertebra. The age-adjusted prevalence of individuals with vertebral deformities was higher among the hip fracture patients than among the reference subjects in both genders, with an odds ratio of 3.6 [95% confidence interval (CI) 1.9-6.6] in men and 2.6 (95% CI 1.7-4.1) in women using deformity criterion -3 SD. Also, the number of vertebrae with deformities (-3 SD) in individuals with one deformity or more was greater among the hip fracture patients than among the reference subjects (in men mean 2.3 versus 1.8, P = 0.007; in women mean 3.3 versus 2.0, P < 0.001). Adjusted for age there were more vertebrae with deformities (-3 SD) among female than among male hip fracture patients (mean 3.3 versus 2.3, P = 0.01). We found no differences in the vertebral deformity rates when comparing patients with a per- or subtrochanteric hip fracture with patients with a cervical hip fracture. In conclusion, there is a relationship between vertebral deformities and hip fractures suggesting that a prevalent vertebral deformity could predict an increased hip fracture risk.

Aged↗

Course of radiographic damage over 10 years in a cohort with early rheumatoid arthritis.

OBJECTIVE: To investigate development of radiographic damage in hands and feet of patients with early rheumatoid arthritis (RA) monitored prospectively for 10 years, and to search for prognostic factors. PATIENTS AND METHODS: 181 patients with early RA (mean disease duration one year) were assessed annually with radiographs of hands and feet during years 0-5 and at year 10. Radiographs were evaluated according to Larsen (range 0-200). Predictive factors for progressive disease for years 0-5 and 5-10 were evaluated by logistic regression analyses. RESULTS: 82/168 (49%) patients had erosions at inclusion and almost all became erosive with time (90% after two years and 96% after 10 years). Radiographic progression was most rapid during the first two years and 75% of all damage occurred during the first five years. The median Larsen score increased from 6 at inclusion to 41 after five years and 54 after 10 years. Only 5.3% of all evaluated joints became maximally eroded, the second metacarpophalangeal joint being the most commonly affected. Mean ESR during the first three months and rheumatoid factor status were significant predictors for radiographic progressive disease, it was not possible to predict non-progressive disease. CONCLUSIONS: Joint damage in hands and feet developed early and progression was most rapid during the first years of disease. The different rates of progression at different stages should be considered in the design of trials of drugs aimed at retarding joint damage. Disease activity at study start influenced the degree of joint damage during the entire 10 years.

Acute Disease↗

Osteochondritis dissecans of the hip.

PURPOSE: To investigate the clinical and radiological characteristics of osteochondritis dissecans (OD) of the hip and the outcome of this condition after treatment. MATERIAL AND METHODS: Twelve male and 3 female patients with OD were retrospectively studied. Six patients had a history of Legg-Calvé-Perthes disease (LCPD) and among them 2 also had had a trauma to the hip. A further 5 had had trauma and 1 a developmental dislocation of the hip (DDH). The remaining 3 patients had no history of previous hip disease or trauma. All patients were examined with plain radiography, 7 with MR, 3 with CT and 2 with hip arthrography. RESULTS: All OD lesions were detected at plain radiography, and most of them were located near the fovea. At MR the lesions had low signal intensity at T1-weighted sequences, and 6/7 had edema or fluid collection in or adjacent to the lesion on T2-weighted sequences. The early treatment in 7 patients was surgery, 2 had had conservative treatment and 6 no treatment. At follow-up 12 years after radiological diagnosis, 5 patients had hip arthrosis, 4 of whom were treated with arthroplasty. All but 3 had reduced hip rotation and all but 2 (with arthroplasty) had load pain. Three of the patients with earlier surgery had not developed arthrosis. CONCLUSIONS: OD lesions are usually well seen with plain radiography. There is a great risk of developing early arthrosis and it seems that early surgery is connected with arthrosis development. Thus only symptomatic treatment is recommended.

Adolescent↗

Ultrasound anatomy in the neonatal clubfoot.

Our objective was to assess clubfoot anatomy by US in newborn babies before and in the early phase of treatment. Reproducible US projections and measurements were carried out on 30 untreated clubfeet in 22 children, consecutively included in the study. The position of the navicular in relation to the head of the talus was visualised in all feet. The mean distance between the medial malleolus and the navicular was significantly shorter in the clubfeet than in normal feet. There was a tendency to medial displacement of the cuboid. Soft tissue thickness at the medial side of the foot was increased in all deformed feet. The measurements showed an acceptable intra- and inter-observer reliability for the different variables assessed ( r=0.71-0.96, Pearson's correlation coefficient). With US it is possible to obtain well-defined planes of investigation that give important information about the clubfoot deformity concerning the talo-crural, the talo-navicular and the calcaneo-cuboid joints. The method is simple enough to be used in everyday clinical practice and we recommend it as a guide during the non-operative treatment and for preoperative planning.

Clubfoot↗

Ultrasound anatomy in the normal neonatal and infant foot: an anatomic introduction to ultrasound assessment of foot deformities.

The aim of this study was to establish guidelines for US assessment of the talo-crural, the talo-navicular and the calcaneo-cuboid joints during the first year of life, which could serve as a reference while studying foot deformities. The feet of 54 healthy children were examined at birth and at the age of 4, 7 and 12 months by using three easily defined and reproducible US projections. With a medial projection the relation of the navicular in relation to the medial malleolus and the head of the talus was studied. A lateral projection revealed the calcaneo-cuboid relationship and a dorsal projection the talo-navicular alignment in the sagittal plane. Normal values for measurements of these cartilaginous relationships were established for the different age groups. Intra- and inter-observer reliability was assessed and found to be acceptable ( r=0.53-0.90, Pearson correlation coefficient). With US it is possible to obtain reproducible planes of investigation that give reliable information about the talo-crural, the talo-navicular and the calcaneo-cuboid relationships during the first year of life.

Female↗

Norian SRS versus functional treatment in redisplaced distal radial fractures: a randomized study in 20 patients.

We compared the use of Norian SRS, an injectable calcium phosphate bone cement, with functional treatment of redisplaced distal radial fractures in a prospective randomized study of 20 patients. The redisplaced fractures were either rereduced and stabilized by Norian SRS, or the displaced position was accepted and was not rereduced. All wrists were immobilized in a short-arm dorsal splint for 1 week, followed by a removable splint for another 3 weeks. The chosen primary effect variable was grip strength at 7 weeks, and this did not differ between the two treatment groups. The clinical results at 6 months in both groups were similar. We conclude that aggressive treatment of redisplaced fractures of the distal radius may be unnecessary in most women aged 50 years or more.

Aged↗

Distinct cytologic features of spindle cell lipoma. A cytologic-histologic study with clinical, radiologic, electron microscopic, and cytogenetic correlations.

BACKGROUND: Spindle cell lipoma (SCL) is a relatively uncommon, benign tumor that usually presents in the subcutaneous fat of adult men. Although some studies have addressed the histologic findings of SCL, only a few descriptions of aspiration cytology findings have been published. The cytologic features are poorly defined, and aspirates from SCL may cause diagnostic problems, because SCL shares some features with other fatty/spindle cell or myxoid lesions, benign as well as malignant. METHODS: Twelve patients underwent fine-needle aspiration (FNA) cytology as the primary diagnostic modality before surgery. FNA findings were evaluated and correlated with histologic features. In addition, radiologic, electron microscopic, and cytogenetic findings were analyzed. The objective of this study was to determine cytologic criteria of SCL by reviewing cytologic specimens in 12 patients with SCL who underwent FNA cytology. RESULTS: All of the tumors arose in adults, and 10 tumors developed in the subcutaneous tissue of the neck, back, or shoulder girdle. Two patients presented with tumors in atypical locations; one in the tongue and one in the cheek. Cytologically, all 12 tumors were characterized by a mixture of mature adipocytes, uniform spindle cells, and collagen bundles and/or fibers in varying proportions. The presence of a myxoid matrix and of mast cells was less specific and occurred in six aspirates. CONCLUSIONS: SCL has a characteristic cytologic appearance that, together with clinical data, helps to exclude low-grade liposarcoma as well as other spindle cell and myxoid lesions.

Adult↗