1	Clinical Application of Weight Bearing and Upright Simulation MRI and CT Imaging John C. Chiu, M.D., FRCS (US), D.Sc. Chief, Neurospine Surgery California Spine Institute Thousand Oaks, California, USA President, ISMISS/SICOT
2
3	Introduction: Weight bearing simulation a way to enhance the accuracy of CT and MR imaging of the lumbar spine
4	Introduction: In upright and weight bearing position, many people experience back pain
5	Introduction: Lumbar symptoms depending on position: Walking and standing give increasing pain Flexion, supine position, slight hip flexion give some symptomatic relief The status of the vertebral disc protrusion and the size of the spinal canal are position and axial load dependent The space in the spinal canal: Increases in flexion Decreases in extension and axial loading
6	Material and Methods:
7	Material and Methods:
8	Result and Discussion:
9	Result and Discussion: Depends on accurate evaluation of the patho-physiology of the spine and the disc Optimal treatment results requires objective findings of specific spinal diagnosis ”Objective” evaluation of the spinal canal and the neural foramen, in cross section and sagital sections is critical In supine relaxed position and in flexion position spinal canal and neural foraminal encroachment can be undetected But positive findings on upright or weight bearing position
10	Result and Discussion: Male 63 years Lumbar discectomy surgeries X2 Progressive intraticable sciatica, DTR, muscle, and sensation alteration of lower extremities
11	Result and Discussion:
12	Result and Discussion: in patients with SCIATICA and/or Neurogenic Claudication A decrease in spinal canal space was found in axial loaded vs. non loaded in:
13	Result and Discussion:
14	Result and Discussion: Male 76 years Operated 3 years before 2 years severe sciatica, impaired walking and standing capacity with motor and sensory disturbances
15	Result and Discussion: Plays a significant role in decision for surgical vs. non surgical treatment Was found to be critical in treatment decision: 72 % of patients with neurogenic claudication 50 % of patient with sciatica
16	Result and Discussion:
17	Result and Discussion: In a group of 20 patients, the treatment decision changed from conservative to operative : in 5 patients (25 %) by 3 spine surgeons and in another 5 patients by at least 1 surgeon Total: 10 20 patients = 50% Comment and conclusion: ” the additional information gained from this technique can influence experienced spine surgeons in their treatment decisions...”
18	Result and Discussion: Female 55 years 2 years neurogenic claudication with Sciatica Decompression Post op pain free full time work
19	Discussion: Lee SU, Hargens AR, Fredericson M, Lang PK. ”Lumbar spine disc heights and curvature: upright posture vs. supine compression harness.” Aviat Space Environ Med. 2003 May;74(5):512-6. It stated ”The spinal compression with specially designed harness has the same effect as the physiologic loading of the spine in the kneeling upright position.” Kimura S, Steinbach GC, Watenpaugh DE, Hargens AR. ”Lumbar spine disc height and curvature responses to an axial load generated by a compression device compatible with magnetic resonance imaging.” Spine. 2001 Dec 1;26(23):2596-600. It stated ”The axial force of 50% body weight in supine posture simulates the upright lumbar spine morphologically.”
20	Discussion: Indications for application: Acute and chronic low back and leg pain Neurogenic claudication Sciatica Longstanding, unexplained LBP
21	Conclusion: Possibility to examine patients in the upright position where they have their symptoms The diagnosis is made in the most exact way available, using a standard MRI or CT scanner A firm basis for the treatment decision for exact pathology, is offered to the spine surgeon for a better outcome Patients should be referred for MRI or CT with weight bearing simulation!
22	Hope you enjoyed this presentation!