Ragnhild Gunderson

Oslo University Hospital, Kristiania (historical), Oslo County, Norway

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Publications (26)44.31 Total impact

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    JI Brox, JE Lange, RB Gunderson, H Steen
    Scoliosis 06/2013; 8(1). · 1.31 Impact Factor
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    Olav Reikerås, Ragnhild B Gunderson
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    ABSTRACT: In a prospective manner to evaluate the range of acetabular component anteversion actually achieved by the use of a cup positioner in cementless revision and primary THA. We operated 71 patients with cementless primary THA, and 26 patients with cementless acetabular revision surgery. We aimed to obtain cup anteversion of 10 to 30° with an impactor-positioner. In all cases we used elevated liners and a ceramic head with diameter 28. At 3 months postoperatively the component versions were measured using CT with the patient in supine position. The acetabular component version in the primary hips ranged from 28° of retroversion to 42° of anteversion with a mean of 17.4 ± 14.0°, while the cup version in the revision hips ranged from 4° of retroversion to 32° of anteversion with a mean of 15.0 ± 9.6°(p=0.427). The anteversion of 40 (56%) of the primary acetabular components were within the target zone of 10 to 30°, while 19 (27%) were below the target zone and and 12 (17%) were above the target range. The anteversion of 19 (73%) of the revision acetabular components were within the target zone, while 6 (23%) were below the target zone and 1 (4%) were above the target range. The differences in distribution between the primary and revision operations were not significant (p=0.183). The intraoperative estimation of acetabular anteversion by free hand technique in many cases was not within the intended range of 10 to 30° in either primary or revision THA and with no differences between the two series.
    The Open Orthopaedics Journal 01/2013; 7:600-4.
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    ABSTRACT: Deformity after slipped upper femoral epiphysis (SUFE) can cause cam-type femoroacetabular impingement (FAI) and subsequent osteoarthritis (OA). However, there is little information regarding the radiological assessment and clinical consequences at long-term follow-up. We reviewed 36 patients (43 hips) previously treated by in situ fixation for SUFE with a mean follow-up of 37 years (21 to 50). Three observers measured the femoral head ratio (FHR), lateral femoral head ratio (LFHR), α-angle on anteroposterior (AP) and frog-leg lateral views, and anterior femoral head-neck offset ratio (OSR). A Harris hip score < 85 and/or radiologically diagnosed osteoarthritis (OA) was classified as a poor outcome. Patients with SUFE had significantly higher FHR, LFHR and α-angles and lower OSR than a control group of 22 subjects (35 hips) with radiologically normal hips. The interobserver agreement was less, with wider limits of agreement (LOA), in hips with previous SUFE than the control group. At long-term follow-up abnormal α-angles correlated with poor outcome, whereas FHR, LFHR and OSR did not. We conclude that persistent deformity with radiological cam FAI after SUFE is associated with poorer clinical and radiological long-term outcome. Although the radiological measurements had quite wide limits of agreement, they are useful for the diagnosis of post-slip deformities in clinical practice.
    Journal of Bone and Joint Surgery - British Volume 11/2012; 94(11):1487-93. · 2.69 Impact Factor
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    ABSTRACT: BACKGROUND:Although arthroscopic techniques are the most common procedures today when reconstructing the anterior cruciate ligament (ACL), many surgeons still prefer the open and/or 2-incision techniques. HYPOTHESIS:There are no differences in knee function or prevalence of knee osteoarthritis (OA) in patients who have undergone the open versus endoscopic technique for ACL reconstruction using the patellar tendon autograft. STUDY DESIGN:Randomized controlled trial; Level of evidence, 2. METHODS:Sixty-seven patients with subacute or chronic rupture of the ACL were randomly assigned to open (OPEN) (n = 33) or endoscopic (ENDO) (n = 34) reconstruction. Function was evaluated by the Cincinnati knee score, single-legged hop tests, and isokinetic muscle strength tests. The radiographs were classified according to the Kellgren and Lawrence (KL) classification system, defining grade 2 or more as the cutoff point for knee OA. The Insall-Salvati ratio and the Blackburne-Peel ratio were used to calculate the patellar position and height. RESULTS:Mean age at inclusion and at the 12-year follow-up evaluation was 27.9 ± 8.6 and 39.8 ± 8.6 years, respectively. At 12-year follow-up, 53 patients (79%) were eligible for evaluation. There were no significant differences between the 2 surgical procedures with respect to the pain, function, muscle strength, hop tests, patellar height, or the prevalence of OA. The prevalence of OA was high in the tibiofemoral joint on the operated side, 79% and 80% in the OPEN and ENDO groups, respectively. For the uninvolved knee, the corresponding numbers were 36% and 21%. CONCLUSION:This study suggests that the open procedure does not produce more functional problems or osteoarthritis compared with the endoscopic technique up to 12 years postoperatively.
    The American journal of sports medicine 09/2012; · 3.61 Impact Factor
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    ABSTRACT: PURPOSE: To investigate the prevalence of patellofemoral osteoarthritis (OA) and to explore the association between radiographic patellofemoral OA and symptoms and function 12 years after anterior cruciate ligament (ACL) reconstruction. METHODS: The study participants (n = 221) were consecutively included at the time of an ACL reconstruction in the period from 1990 to 1997. Knee laxity (KT-1000), isokinetic quadriceps strength, triple jump, stair hop, and the Cincinnati knee score were measured 6 months, 1 year, 2 years, and 12 years after surgery. At the 12-year follow-up, visual analogue scale for pain, the Knee injury and Osteoarthritis Outcome Score, the Tegner activity scale, and radiographic examination (Kellgren and Lawrence score) were added. To analyse the association between patellofemoral OA, symptoms, and function, binary regression analyses presenting odds ratios and 95 % confidence intervals were used. The analyses were adjusted for age, gender, and body mass index. RESULTS: One hundred and eighty-one of the 221 subjects (82 %), including 76 females (42 %) and 105 males (58 %), were evaluated at the 12.3 ± 1.2-year follow-up. Mean age at the follow-up was 39.1 ± 8.7 years. Additional meniscal or chondral injuries at the time of reconstruction or during the follow-up period were detected in 116 subjects (64 %). Radiographic patellofemoral OA was found in 48 subjects (26 %), including 3 subjects with isolated patellofemoral OA (1.5 %). Those with patellofemoral OA were older, had more tibiofemoral OA, and had significantly more symptoms and impaired function compared with those without patellofemoral OA. CONCLUSIONS: Patellofemoral OA was found in 26 % 12 years after ACL reconstruction. Patellofemoral OA was associated with increased age, tibiofemoral OA, increased symptoms, and reduced function. It is of clinical importance to include functional and radiographic assessment of the patellofemoral joint in the examination of long-term consequences following an ACL reconstruction. LEVEL OF EVIDENCE: II.
    Knee Surgery Sports Traumatology Arthroscopy 08/2012; · 2.68 Impact Factor
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    O Reikerås, R B Gunderson
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    ABSTRACT: The recommended range of anteversion of the components in total hip arthroplasty (THA) is between 10 and 30°, but the intraoperative estimation of these versions may be inadequate. The components anteversion in primary cementless THA using straight stem and hemispherical cup is not significantly different from the native anteversion of the hip joint. To evaluate in a prospective manner the range of anteversion currently achieved in cementless THA. Five senior surgeons operated 91 patients with primary cementless THA. We used a straight press fit stem and a hemispherical press fit cup. We aimed to obtain femoral anteversion of 10 to 30°, acetabular anteversion of 10 to 30° and a global combined anteversion of 25 to 55°. Cup position was checked with an impactor-positioner, and stem position was determined with the knee flexed 90°. In all cases we used elevated liners and 28 mm diameter ceramic heads. At 3 months postoperatively the component versions were measured using a General Electric LightSpeed Pro 16 (Milwaukee, Wi, USA) with the patient in supine position. Femoral component measurements ranged from 17° of retroversion to 60° of anteversion with a mean of 23.0±11.8°. Similarly, acetabular component version ranged from 28° of retroversion to 46° of anteversion with a mean of 18.5±13.7°. There were no correlations to the native femoral and acetabular versions. Only 55 hips (60.4%) were within the accepted range of 25 to 55° of combined anteversion, but none of the cases dislocated during a follow-up of 2 years. In cementless THA with our operative technique, the intraoperative estimation of femoral and acetabular anteversion, in many cases, resulted to be inadequate in relation to the intended range of 10 to 30° of anteversion.
    Orthopaedics & Traumatology Surgery & Research 09/2011; 97(6):615-21. · 1.06 Impact Factor
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    ABSTRACT: ABSTRACT: It is recommended that research in patients with idiopathic scoliosis should focus on short- and long-term patient-centred outcome. The aim of the present study was to evaluate outcome in patients with late-onset juvenile or adolescent idiopathic scoliosis 16 years or more after Boston brace treatment. 272 (78%) of 360 patients, 251 (92%) women, responded to follow-up examination at a mean of 24.7 (range 16 - 32) years after Boston brace treatment. Fifty-eight (21%) patients had late-onset juvenile and 214 had adolescent idiopathic scoliosis. All patients had clinical and radiological examination and answered a standardised questionnaire including work status, demographics, General Function Score (GFS) (100 - worst possible) and Oswestry Disability Index (ODI) (100 - worst possible), EuroQol (EQ-5D) (1 - best possible), EQ-VAS (100 - best possible), and Scoliosis Research Society - 22 (SRS - 22) (5 - best possible). The mean age at follow-up was 40.4 (31-48) years. The prebrace major curve was in average 33.2 (20 - 57)°. At weaning and at the last follow-up the corresponding values were 28.3 (1 - 58)° and 32.5 (7 - 80)°, respectively. Curve development was similar in patients with late-onset juvenile and adolescent start. The prebrace curve increased > 5° in 31% and decreased > 5° in 26%. Twenty-five patients had surgery. Those who did not attend follow-up (n = 88) had a lower mean curve at weaning: 25.4 (6-53)°. Work status was 76% full-time and 10% part-time. Eighty-seven percent had delivered a baby, 50% had pain in pregnancy. The mean (SD) GFS was 7.4 (10.8), ODI 9.3 (11.0), EQ-5D 0.82 (0.2), EQ-VAS 77.6 (17.8), SRS-22: pain 4.1 (0.8), mental health 4.1 (0.6), self-image 3.7 (0.7), function 4.0 (0.6), satisfaction with treatment 3.7 (1.0). Surgical patients had significantly reduced scores for SRS-physical function and self-image, and patients with curves ≥ 45° had reduced self-image. Long-term results were satisfactory in most braced patients and similar in late-onset juvenile and idiopathic adolescent scoliosis.
    Scoliosis 08/2011; 6:18. · 1.31 Impact Factor
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    The American journal of sports medicine 04/2011; 39(4):NP3; author reply NP3-4. · 3.61 Impact Factor
  • O. Reikerås, R. B. Gunderson
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    ABSTRACT: Background The recommended range of anteversion of the components in total hip arthroplasty (THA) is between 10 and 30°, but the intraoperative estimation of these versions may be inadequate. Hypothesis The components anteversion in primary cementless THA using straight stem and hemispherical cup is not significantly different from the native anteversion of the hip joint. Objectives To evaluate in a prospective manner the range of anteversion currently achieved in cementless THA. Materials and methods Five senior surgeons operated 91 patients with primary cementless THA. We used a straight press fit stem and a hemispherical press fit cup. We aimed to obtain femoral anteversion of 10° to 30°, acetabular anteversion of 10° to 30° and a global combined anteversion of 25° to 55°. Cup position was checked with an impactor-positioner, and stem position was determined with the knee flexed 90°. In all cases we used elevated liners and 28 mm diameter ceramic heads. At 3 months postoperatively the component versions were measured using a General Electric LightSpeed Pro 16 (Milwaukee, Wi, USA) with the patient in supine position. Results Femoral component measurements ranged from 17° of retroversion to 60° of anteversion with a mean of 23.0° ± 11.8°. Similarly, acetabular component version ranged from 28° of retroversion to 46° of anteversion with a mean of 18.5° ± 13.7°. There were no correlations to the native femoral and acetabular versions. Only 55 hips (60.4 %) were within the accepted range of 25° to 55° of combined anteversion, but none of the cases dislocated during a follow-up of two years. Conclusion In cementless THA with our operative technique, the intraoperative estimation of femoral and acetabular anteversion, in many cases, resulted to be inadequate in relation to the intended range of 10° to 30° of anteversion. Level of evidence Level III prospective diagnostic.
    Resuscitation 01/2011; 97(6):600-601. · 4.10 Impact Factor
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    ABSTRACT: To identify risk factors for knee osteoarthritis (OA) 10-15 years after anterior cruciate ligament (ACL) reconstruction. We hypothesized that quadriceps muscle weakness after ACL reconstruction would be a risk factor for radiographic and symptomatic radiographic knee OA 10-15 years later. Subjects with ACL reconstruction (n=258) were followed for 10-15 years. Subjects with unilateral injury at the 10-15-year followup were included in the present study. Outcomes included the Cincinnati knee score, knee joint laxity, hop performance, and isokinetic muscle strength tests at 6 months, 1 year, and 2 years postoperatively. At the 10-15-year followup, radiographs were taken and graded according to the Kellgren/Lawrence classification (range 0-4). Of the 212 subjects (82%) assessed at the 10-15-year followup, 164 subjects had unilateral injury. The mean±SD age at ACL reconstruction was 27.4±8.5 years. Increased age (odds ratio [OR] 1.06, 95% confidence interval [95% CI] 1.01-1.11) and meniscal injury and/or chondral lesion (OR 2.05, 95% CI 1.00-4.20) showed significantly higher odds for radiographic knee OA. Low self-reported knee function 2 years postoperatively (OR 0.95, 95% CI 0.92-0.98) and loss of quadriceps strength between the 2-year and the 10-15-year followup (OR 1.00, 95% CI 1.00-1.01) showed significantly higher odds for symptomatic radiographic knee OA. Quadriceps muscle weakness after ACL reconstruction was not significantly associated with knee OA. This study detected no association between quadriceps weakness after ACL reconstruction and knee OA as measured 10-15 years later.
    Arthritis care & research. 12/2010; 62(12):1706-14.
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    ABSTRACT: Few prospective long-term studies of more than 10 years have reported changes in knee function and radiologic outcomes after anterior cruciate ligament (ACL) reconstruction. To examine changes in knee function from 6 months to 10 to 15 years after ACL reconstruction and to compare knee function outcomes over time for subjects with isolated ACL injury with those with combined ACL and meniscal injury and/or chondral lesion. Furthermore, the aim was to compare the prevalence of radiographic and symptomatic radiographic knee osteoarthritis between subjects with isolated ACL injuries and those with combined ACL and meniscal and/or chondral lesions 10 to 15 years after ACL reconstruction. Cohort study; Level of evidence, 2. Follow-up evaluations were performed on 221 subjects at 6 months, 1 year, 2 years, and 10 to 15 years after ACL reconstruction with bone-patellar tendon-bone autograft. Outcome measurements were KT-1000 arthrometer, Lachman and pivot shift tests, Cincinnati knee score, isokinetic muscle strength tests, hop tests, visual analog scale for pain, Tegner activity scale, and the Kellgren and Lawrence classification. One hundred eighty-one subjects (82%) were evaluated at the 10- to 15-year follow-up. A significant improvement over time was revealed for all prospective outcomes of knee function. No significant differences in knee function over time were detected between the isolated and combined injury groups. Subjects with combined injury had significantly higher prevalence of radiographic knee osteoarthritis compared with those with isolated injury (80% and 62%, P = .008), but no significant group differences were shown for symptomatic radiographic knee osteoarthritis (46% and 32%, P = .053). An overall improvement in knee function outcomes was detected from 6 months to 10 to 15 years after ACL reconstruction for both those with isolated and combined ACL injury, but significantly higher prevalence of radiographic knee osteoarthritis was found for those with combined injuries.
    The American journal of sports medicine 11/2010; 38(11):2201-10. · 3.61 Impact Factor
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    International Orthopaedics 02/2010; 34(5):773-4; author reply 775-6. · 2.32 Impact Factor
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    ABSTRACT: This study entails a prospective evaluation of lumbar closing wedge osteotomy for correction of thoracolumbar kyphotic deformity in ankylosing spondylitis. Twenty patients with a median age of 52 years (range, 26-70) underwent follow-up at one year. The lumbar closing wedge osteomtomy was stabilised by metallic rods fixed by transpedicular screws. Outcome measures were quality of life (EuroQol), occiput-to-wall distance, pain, fatigue, complications, technical and radiological evaluation. The technical result was good in 16 and fair in four patients; two had neuropraxia. The deformity was reduced an average of 17 degrees (95% confidence interval 15-25 degrees) at one-year follow-up. Pain during activity, pain at night, and fatigue were significantly reduced. EuroQol improved from 0.42 to 0.69 (p = 0.002) and occiput-to-wall distance from 26 to 18 cm (p = 0.005). Functional outcome was improved after lumbar closing wedge osteotomy in ankylosing spondylitis.
    International Orthopaedics 06/2008; 33(4):1049-53. · 2.32 Impact Factor
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    ABSTRACT: It is well accepted that youth and high activity levels are among the factors that increase the risk of mechanical failure of total hip prostheses. However, there are few reports of long-term results in very young patients. In this study, we evaluated the results of total 49 hip replacements (THRs) using an uncemented total hip prosthesis in 44 patients (28 females) who were 30 years or younger (range: 15-30 years). The diagnosis was ostearthritis due to congenital dislocations in 28 patients, with the remaining patients having diagnoses of sequelae of fracture, infection, Calve-Legg-Perthes disease, avascular necrosis, chondrodystrophia and epiphyseal dysplasia. In all cases we used an uncemented straight stem fully coated with hydroxyapatite (HA). In 36 cases we used a hemispherical cup inserted with press fit, and in seven cases we used a hemispherical screw cup. The patients were evaluated ten to 16 years (mean: 13 years) after the operation by radiographic and clinical examinations, including the Harris Hip, WOMAC and EuroQol-5D scores. In a sub-group of nine patients with a unilateral prosthesis, the muscle strength of the quadriceps and hamstrings was tested using a Cybex 6000. None of the stems were revised at the follow-up examination, and all were classified as well integrated, with no signs of radiological loosening. Twenty-four hips had revision of the acetabular component due to mechanical failure. The Harris Hip score was, on average, 88 (range: 62-100), the WOMAC score 80 (range: 37-100) and the EuroQol score 0.68 (range: -0.14-1). Isokinetic muscle strength testing showed that seven of the nine tested patients were weaker on the operated side. In conclusion, we found mechanical failures at the acetabular side, but excellent results with a fully HA-coated femoral stem, with no revisions after ten to 16 years.
    International Orthopaedics 05/2008; 32(2):203-8. · 2.32 Impact Factor
  • Olav Reikerås, Ragnhild B Gunderson
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    ABSTRACT: There are many studies on the short and medium term results of hydroxyapatite (HA) coated acetabular components, but information on survival in the longer run is sparse. In this paper, we report 11 to 16 years follow up results of HA coated threaded versus HA coated hemispherical press fit cups. During the years 1988-1993, we performed 323 primary total hip replacements in 276 patients with an HA coated acetabular component. In 128 cases we used a HA coated threaded cup, and in 195 cases a HA coated hemispherical press fit cup was inserted. There were 189 women and 87 men aged 15-79 (mean 48) years. During follow-up, 14 patients died and 21 patients would not come for the follow-up examination as they were doing quite well with their prostheses. These patients were censored at their last control examination. This left 241 patients (287 hips) followed for 11 to 16 (mean 13) years after the operation. During the follow-up period 48 press fit cups and 9 threaded cups were revised, none because of infection. Survival analyses indicated a cumulative survival of the threaded HA coated cup of 0.91 (95% CI: 0.86-0.97) at 16 years with one patient at risk. The cumulative survival of the HA coated press fit cup was 0.74 (0.69-0.80) at 15 years with no patient at risk. The difference is significant (P = 0.0002). Wear and age was significantly associated with revision (P < 0.0001 and 0.0002, respectively), and wear was significantly (P < 0.0001) associated with osteolysis. These results indicate that HA coated threaded cups provide satisfactory bony interlock to resist force loads in the long run whereas the HA coated hemispherical press fit cups do not.
    Archives of Orthopaedic and Trauma Surgery 11/2006; 126(8):503-8. · 1.36 Impact Factor
  • Olav Reikerås, Ragnhild B Gunderson
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    ABSTRACT: The outcome of femoral component revision with either cemented or proximally coated stems has been disappointing, but revision with extensively coated stems has been promising. We report long-term outcome of a grit-blasted titanium stem entirely plasma sprayed with hydroxyapatite (HA), in femoral revision surgery. During 1988 to 1993, we performed 66 femoral revisions in 65 patients (49 women) aged mean 58 (28-86) years. 3 patients died before the 10-year follow-up and 4 did not come for the follow-up examination because they had no hip problems, as confirmed by telephone and by a written reply. 1 of these, however, was previously controlled at 10 years. Thus, 59 patients (60 hips) were followed by clinical and radiographic analysis for 10-16 years after femoral stem revision. 1 stem was re-revised due to mechanical failure, and none were revised because of infection. We noticed a low degree of proximal bone loss and a low incidence of distal bone hypertrophy. These observations indicate no significant net transfer of stress proximally to distally, and a somewhat physiological weight distribution from the stem to the femoral bone. The bone changes confirmed a well-fixed femoral component in asymptomatic patients. Our findings indicate good long-term results with a fully HA-coated stem in femoral revision surgery.
    Acta Orthopaedica 03/2006; 77(1):98-103. · 2.74 Impact Factor
  • Olav Reikerås, Ragnhild B Gunderson
    Acta Orthopaedica - ACTA ORTHOP. 01/2006; 77(1):98-103.
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    ABSTRACT: A randomized study. To compare muscle strength, cross-sectional area, and density of the back muscles in two categories of patients with chronic low back pain, randomized to either lumbar fusion or cognitive intervention and exercises. In two clinical trials, patients with chronic low back pain plus disc degeneration and postlaminectomy syndrome, respectively, were randomized to either lumbar fusion or cognitive intervention and exercises. We have previously reported that results for the primary outcome were similar at the 1-year follow-up examination. As the treatment alternatives and test procedures were identical, the two trials were merged into one. A total of 124 patients 25 to 60 years of age were included. Muscle strength, measured by isokinetic test device and by the Biering-Sørensen Test, was measured in 112 patients, and the cross-sectional area and density of the back muscles were measured in 61 patients at the inclusion and at the 1-year follow-up examination. The exercise group performed significantly better in muscle strength than did the lumbar fusion group, with the mean difference at 184 Nm (95% confidence interval, 64-303 Nm; P = 0.003) and for the Biering-Sørensen Test 21 seconds (95% confidence interval, 6-36 seconds; P = 0.006). The density at L3-L4 decreased in the lumbar fusion group but remained unchanged in the exercise group. The mean difference was 5.3 HU (95% confidence interval, 1.1-9.5 HU; P = 0.01). The cross-sectional area was unchanged in both groups. Patients with chronic low back pain who followed cognitive intervention and exercise programs improved significantly in muscle strength compared with patients who underwent lumbar fusion. In the lumbar fusion group, density decreased significantly at L3-L4 compared with the exercise group.
    Spine 02/2004; 29(1):3-8. · 2.16 Impact Factor
  • Anne Keller, Ragnhild Gunderson, Olav Reikerås, Jens I Brox
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    ABSTRACT: A reliability study was conducted. To estimate measurement errors related to equipment and the observer in computed tomography measurements of cross-sectional area and density of paraspinal muscles. Interobserver reliability was not investigated in the current study. Computer tomography (CT) had been used to measure the cross-sectional area and degeneration of the back muscles in patients with low back pain. This study included 31 patients, mean age 47 years, with chronic low back pain. The measurements comprised cross-sectional area (cm2) and density (Hounsfield units [HU]) of the paraspinal muscles at Th12-L1, L3-L4, and L4-L5. To measure the reliability of the equipment and the observer (total reliability), two independent CT scans were performed for each patient. The radiologist traced the cross-sectional area twice within 2 weeks for measurement of the intraobserver reliability. There were no significant differences in the assessments between the first and second CT scans, or between the radiologist's two measurements of the identical slices. The critical difference for the total reliability ranged from 11.3 to 22.8 for the density and from 10.0 to 16.0 for the cross-sectional area. For the cross-sectional area, the measurement error associated with the observer was higher than for the equipment. For the density, the measurement error related to the equipment was higher. The main measurement error was associated with the radiologist for the cross-sectional area and with the CT scanner for the density. The reliability of the CT scan for measuring the cross-sectional area and density of the back muscles is acceptable. The authors do not know definitely whether their results can be generalized because the interobserver and intermachine reliabilities were not investigated.
    Spine 08/2003; 28(13):1455-60. · 2.16 Impact Factor
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    ABSTRACT: The effect of exercise on back muscle cross-sectional area (CSA), density, and strength was evaluated in patients sick-listed for subacute low back pain. Twenty-four patients were randomized into an exercise (n = 11) or a control (n = 13) group. Patients in the exercise group followed a biweekly exercise protocol for 15 weeks. Control patients received usual care. Muscle CSA and density were measured by computed tomography before and after intervention. Isokinetic test of back extensors was conducted simultaneously. Results showed a tendency to increased muscle CSA and density in patients in the exercise group, a significant decrease in muscle CSA at L4-L5 in control group patients, and a significant difference in change between groups in muscle CSA at L4-L5. Back extension strength increased in patients in the exercise group, but the improvement was not significant compared with control group patients. In conclusion, there was a tendency for reversal of muscle atrophy after exercise.
    Journal of Spinal Disorders & Techniques 07/2003; 16(3):271-9. · 1.77 Impact Factor

Publication Stats

294 Citations
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44.31 Total Impact Points

Institutions

  • 2010–2013
    • Oslo University Hospital
      • Department of Orthopaedic Surgery
      Kristiania (historical), Oslo County, Norway
  • 2000–2006
    • University of Oslo
      • Department of Orthopaedics (ORTHO)
      Oslo, Oslo, Norway