Clinical / Clinical Experience / Scientific Presentations & Articles

Scientific Presentations and Articles

The results of clinical trials carried out to date have been presented at a number of leading orthopedic and radiological scientific meetings:

• Radiological Society of North America, 2004, Chicago, USA.
• ASNR, 2003, Washington DC, USA.
• Radiological Society of North America, 2002, Chicago, USA.
• International Symposium, Swiss Spine Institute, 2002, Basel, Switzerland.
• European Society of Musculoskeletal Radiology, 2001, Budapest, Hungary.
• Eurospine 2001, Gothenburg, Sweden.
• Annual Meeting of Orthopaedic Research Society, 2001, San Fransisco, USA.
• Nordic Radiology Congress 2000, Helsinki, Finland.
• First Interdisciplinary World Congress on Spinal Surgery, 2000, Berlin, Germany.
• European Society of Musculoskeletal Radiology, October 1998.
• Nordic Congress of Radiology, Copenhagen, 1998.
• International Society of the Study of the Lumbar Spine, 1997, Singapore.
• Annual Meeting of the Nordic Scoliosis Society, 1997, Singapore.
• The Meeting of the European Spine Society, 1994, Madrid, Spain.
• The Annual Meeting of the Nordic Orthopaedic Society, 1993, Reykjavik, Iceland.

• Hiwatashi A, Danielson B, Moritani T, Westesson P-L, Bakos R, Rodenhause T, Pilcher:
  "Axial loading during MR imaging can influence treatment decision for symptomatic spinal stenosis" AJNR 2004;Feb: 1-5. See below
• Saifuddin A, MacSweeney E, Lehovsky J:
  Case report: Development of lumbar high intensity zone on axial loaded MRI.
  Spine 2003; 28: 449-52.
  
  A 55 year-old female with chronic low back pain was imaged with lumbar spine MRI before and following axial loading. Following axial loading, posterior central HIZs were identified at the L2/3 and L4/5 levels. We postulate that lumbar spine MRI with axial loading may increase the sensitivity of MRI for the detection of radial annular tears.
• Danielson B, Willén J, 2003
  "Axially loaded CT and MRI of the lumbar spine - A method to achieve an accurate radiological diagnosis in patients with low back pain" Chapter in: "Advances in Spinal Fusion". Marcel Dekker, Inc, New York. Published 2003. Review
• Byass O:
  "Dynamic lumbar spine stenosis"
  Presentation at Philips network meetings, June 11th 2003
• Danielson B:
  "Application of DynaWell compression device for lumbar spine imaging"
  Presentation at Philips network meetings, June 11th 2003
• Lee S-U, Hargens AR, Fredrickson M, Lang PK, January, 2003
  "Lumbar spine disc heights and curvature: upright posture vs supine compression harness"
  Aviat Space Environ Med. 2003 May;74(5):512-6.
  
  15 healthy subjects were scanned supine in MRI and after that in axial compression with the DynaWell device. They were also scanned in kneeling position between two vertically oriented magnetic coils. Anterior disc height increased and posterior disc height decreased after spinal compression and in upright posture. The spinal compression harness (= the DynaWell L-spine device) has the same effect as the physiologic loading on the spine in the kneeling upright position. The harness shows some promises as a tool to increase the diagnostic capabilities of a conventional MRI system.
• Hiwatashi A, Moritani T, Danielson B, Westesson P-L, 2003
  "MR imaging with Axial Loading of the Spine alters treatment decisions in about 30% of cases"
  Presentated at ASNR, Washington, DC, USA, April 27 - May 2, 2003
  
  20 patients with spinal stenosis were imaged with regular MRI and axially loaded MRI. 3 experienced neurosurgeons were asked for their treatment decision based on the regular MRI images and clinical information. They were then asked for a treatment decision based on also axially loaded images (with the DynaWell L-Spine device). In 5/20 patients (25%), all of the three neurosurgeons changed the treatment decision from conservative to decompressive surgery when shown the axial loaded images. In one other case two surgeons changed and in two additional cases one surgeon changed his treatment in the same fashion. Axial loading during MRI may influence treatment decision.
• MacSweeney E, Saifuddin A, Blease S, Noordeen MH, Taylor BA
  "Assessment of Cobb angle in idiopathic scoliosis on axial loaded MRI. Preliminary results"
  Presented at BRC 2003
  
  A prospective study on 5 females with idiopathic scoliosis was performed. The scoliosis angles on pre-referral erect radiographs, unloaded and loaded MRI were measured and compared. Initial results suggest that axial loaded MRI using the Dynawell Compression device may allow comparative measurement of Cobb angle to erect radiographs in the thoracolumbar region, but not in the thoracic region. The technique has the potential to replace radiography and thus reduce radiation burden to young adolescents with some types of idiopathic scoliosis.
• Danielson B
  "The diagnostic effect of axial loading of the lumbar spine during CT and MRI in patients with degenerative disorders"
  Presentation at The 44th Congress of Taiwan Ortopedic Association, Tainan, Taiwan; April 2003
• Danielson B, Hiwatashi A, Moritani T, Westesson, 2002
  "Axial Loading of the Spine During MR Imaging Increases Sensitivity for Spinal Stenosis"
  Presentation at RSNA, Chicago, USA, December 1-6, 2002
  
  Images of 20 MRI examined patients were evaluated with a short clinical history by 2 neurosurgeons. First MRI images without and at another occasion with axial load were shown and the surgeons were asked for their treatment decision. In 6/20 patients (33%) the surgeons changed their treatment decision from conservative to operative when the axial loaded images were shown. Axial loaded MRI examination was concluded to affect the treatment decision in selected patients.
• Amendy U, Watura R, Goddard P, 2002
  "Application of a loading device (DynaWell) for the imaging of spinal stenosis"
  Presentation at UK Radiological Congress (UKRC) in Birmingham, 2002-06-10
  
  10 Patients and 3 volunteers with symptoms of spinal stenosis, normal Doppler examination, normal conventional CT/MRI or symptoms disproportionate to findings, fit for surgery were examined with axial loading with 50% of their body weight at MRI. Axial loading significantly contributed in 6 out of 10 patients to the diagnosis.
  Narrowing of the spinal canal was enhanced in 4 patients. A facet joint cyst was seen in two patients and increase of a lateral recess stenosis in one patient. Imaging with axial loading of the lumbar spine can be a very useful supplement in selected patients with suspected spinal stenosis and equivocal MRI findings.
• Kahn, S. Hemmer, J. F. Erly, W. K. Seeger, J. F, 2002
  "MR Scanning of the Lumbosacral Spine during Simulated Upright Positioning"
  Presentation at Symposium and ASNR, 4th Meeting 13-17 May 2002, Vancouver
  
  200 disc levels in 50 patients were evaluated in the usual supine and also in axial loaded position. Sagittal scans revealed antero- posterior diameter reduction of the sac in 50% of levels and axial scans showed cross sectional area reduction in 64% of levels.33% of patients progressed from a non critical to a critical stenosis of the dural sac (75mm2) with axial loading.25% of patients with one critical stenotic level developed a second critically stenotic level with axial loading. Previously undetected synovial cysts or diverticula developed at 20 levels during axial loading.
• Schöllhammer M, Schmid GJ, Willburger R, Köster O, Jergas M, 2002
  "MRT der LWS unter axialer Belastung"
  Poster at 83. Deutscher Röntgenkongress, May 2002-05-17
  
  33 patients were examined with MRI with axial load. DCSA (Dural cross sectional area) was measured from L2-S1. Results showed that a decrease in DCSA was seen in 22/33(67%) of the patients. The authors claim that compression examination with the DynaWell L-Spine simulates the standing position and can give clinically relevant decrease in DCSA through disc protrusion.
• Danielson B, Willén J, 2001
  "Axially loaded Magnetic Resonance Imaging of the lumbar spine in asymptomatic individuals"
  Spine 2001; 26: 2601-06.
  
  43 asymptomatic subjects were examined with different magnitude of axial load (25% and 50% of the body weight) and different duration of the load (5,20,40,60 min). A significant decrease in DCSA was found in 24 of the 43 cases, (56%). The decrease was found after loading with 50% of the body weight by all patients where the load was applied for at least 5 minutes.
• Willén J, Danielson BI, 2001
  "The diagnostic effect from axial loading of the lumbar spine during Computed Tomography and Magnetic Resonance Imaging in patients with degenerative disorders"
  Spine 2001; 26: 2607-14.
  
  Additional valuable information (a verified spinal stenosis, recess stenosis, foraminal stenosis or synovial cyst in axial compression) was found in 50/172 patients (29%) during examination in axial loading. In the different diagnostic groups additional valuable information was found in 72% of patients with neurogenic claudication (symptoms of spinal stenosis). In patients with low back pain without neurogenic claudication or sciatica the corresponding figure is 0%.
• Kimura S, Steinbach G, Watenpaugh D, Hargens A, 2001
  "Lumbar spine disc height and curvature responses to an axial load generated by a compression device compatible with magnetic resonance imaging"
  Spine 2001; 26: 2596-2600.
  
  Eight young volunteers were examined with MRI with axial load in supine position. Intervertebral angle at L4-L5 was not changed but disc height decreased significantly. The DynaWell L-Spine device provides close simulation of the lumbar spine in upright posture.
• Danielson B, Willén J, 2001
  "Axially loaded MRI of the lumbar spine in asymptomatic individuals"
  Poster at Eurospine September 2001
  See above
• Kimura S, Chang E, Steinbach G, Stimson E, Hesselink J, Garfin S, Hargens A, 2001
  "Narrowing of the dural tube during axial loading of the cervical spine in patients with cervical degenerative diseases"
  Poster at the Orthop Res Soc Meeting, July 2001
  
  Seven patients with symptoms from the cervical spine were examined with axial compression using a special device. The A-P distance as well as the CSA of the dural tube at C6/7 decreases significantly during axial compression.
• Willén J, Danielson BI, Schönström N, 2001
  "Kinematic MRI of the lumbar spine: Assessment in the axial loaded, supine position"
  Chapter in "Kinematic MRI of the Joints" edited by Shellock FG, Powers CM, March 2001, available through CRC Press, ISBN: 0-8493-0807-0.
  
  Review with description of the advantages of the use of kinematic MRI in the evaluation of lumbar spine disorders.
• Schönström N, Willén J, 2001
  "Imaging Lumbar Spinal Stenosis"
  Radiologic Clinics of North America 2001; 39 (1): 31-53.
  
  Review article on spinal stenosis where results from earlier articles on axial loading are reported.
• Kimura S, Steinbach G, Adusumalli M, Abitbol J, Watenpaugh D, Hargens A, 2000
  "Lumbar spine length and curvature responses to an axial load using an MRI-compatible compression harness"
  Presented at the First Interdisciplinary World Congress on Spinal Surgery, Berlin, Germany, Aug 27 - Sep 1, 2000: 319-323.
  
  See above
• Tallroth K, Lindgren K - A, Willén J, 2000
  "Axial Loading of the Lumbar Spine in CT Scanning"
  Poster at the Nordic Orthopaedic Federation, Tampere, Finland, June 2000.
  
  100 patients were examined from L3-S1 with CT in supine without and with axial compression. In 25 levels an absolute spinal stenosis was seen only in axial compression.
• Tallroth K, 2000
  "Axial loading of the lumbar spine"
  Presented at the 54th Nordic Radiological Congress, Helsinki, Finland, May 28 - 31, 2000
  See above
• Danielson BI, Willén J, Gaulitz A, Niklason T, Hansson TH, 1998
  "Axial loading of the spine during CT and MR in patients with suspected lumbar spinal stenosis"
  Acta Radiologica 1998; 39: 604-611.
  
  A minimum difference in dural cross sectional area of 15mm2 between non-loaded and loaded CT or MRI examination was found to be significant. In 40/50, i. e. 80% of CT examined patients and in 26/34, i. e. 76% MRI examined patients a significant difference in DCSA between non-loaded and loaded examination was found. For an adequate evaluation of the DCSA in patients with suspected lumbar spinal stenosis, a loaded examination should be performed.
• Tallroth K, 1998
  "Plain CT of the degenerative lumbar spine"
  European Journal of Radiology 1998; 27: 206-213.
  
  Here, the possibility of axial loading is mentioned.
• Willén J, Danielson BI, Gaulitz A, Niklason T, Schönström N, Hansson TH, 1997
  "Dynamic effects on the lumbar spinal canal. Axially loaded CT - Myelography and MRI in patients with sciatica and/or neurogenic claudication"
  Spine 1997; 22 (24): 2968-2976.
  
  84 patients were examined after axial loading with CT (50) and MRI (34). In 66 patients a statistically significant reduction of the dural cross sectional area was found in at least one site during axial compression in slight extension. Of the investigated patients, 29 passed the borderlines for relative (100mm2) or absolute stenosis (75mm2) in 40 sites. The diagnostic specificity of the spinal stenosis will increase considerably when the patient is subject to an axial load.