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Uri M Ahn

Publications and source records attributed to Uri M Ahn.

8 recordsLinked to original sources
PubMed2007

Mechanical neck pain and cervicogenic headache.

Mechanical neck pain is a very common symptom that may occur with cervical spondylosis. It can be associated with cervical radiculopathy and myelopathy or can occur in isolation. Neck pain can result from a variety of causes, including trauma, tumor, infection, and degeneration. The presentation of axial neck pain varies. This article highlights the presentation, differential diagnosis, and appropriate work-up for the patient who presents with mechanical neck pain.

Cervical Vertebrae↗
PubMed2003

Operative treatment of the patient with neck pain.

Most patients with axial neck pain and cervical radiculopathy can be managed conservatively. Surgical intervention for radiculopathy is considered only when conservative management has failed unless the neurologic deficits are very significant. In cases of myelopathy, surgery may be considered earlier, but if the myelopathy is mild, conservative treatment and close observation are still appropriate. For patients with axial neck pain, surgery is generally not considered except for rare cases caused by single- or two-level degenerative disk disease with severe and unrelenting pain. There are many surgical options for the patients with the degenerative cervical spine, but the indications are different. Surgical intervention involves a complete understanding of the disease process both from physical examination and from radiographic studies. If surgery is undertaken without appropriate clinical correlation, poor results often occur. Although the operative planning is the responsibility of the surgeon. the referring physician should also have some awareness of the basic principles behind the different surgeries.

Cervical Vertebrae↗
PubMed2003

Evaluation of registration methods used in frameless stereotactic surgery for the lumbar and cervical regions of the spine.

Computer-assisted pedicle screw insertion is feasible but has proved to be problematic. The purpose of this study was to detail the accuracy of registration techniques and pedicle screw insertion using a frameless stereotactic system. Two registration techniques were evaluated on a model spine. The frameless stereotactic system was then used to insert 26 pedicle and 8 lateral mass screws in human cadavers. For posterior vertebral elements, trajectory accuracy was 2.5 +/- 1.0 mm between T12 and L5 and 2.2 +/- 0.9 mm between C2 and T1. Registration of the anterior elements, however, was less accurate. Despite this flaw, all screws were inserted without penetrating the cortex. Screw trajectory was accurate to 2 degrees. The main limitation of frameless stereotactic surgery in the spine stems from the fact that only the posterior vertebral elements are used during registration. Despite this flaw, the system placed all screws correctly. Given these limitations, we believe that this system is most useful for locating the screw insertion point and providing a trajectory in the pedicle.

Bone Screws↗
PubMed2002

Functional outcome and radiographic correction after spinal osteotomy.

STUDY DESIGN: A prospective clinical trial to study the radiographic parameters and functional outcome in patients undergoing spinal osteotomy. OBJECTIVES: To determine whether correction of specific radiographic parameters is associated with improved functional outcome. SUMMARY OF BACKGROUND DATA: Although vertebral osteotomies have been shown to improve functional outcome in patients with spinal deformity, no prospective reports have studied whether correction of specific radiographic parameters is associated with improvement in functional outcome. METHODS: Eighty-three patients with fixed sagittal and/or coronal deformity were followed over a 7-year period. Patients were evaluated clinically and radiographically and completed a SF-36 Health Survey and American Academy of Orthopedic Surgeons Modems Instrument questionnaire. Spearman correlation analysis was used to determine the association between correction of radiographic parameters and functional outcome. RESULTS: Mean preoperative lumbar lordosis measured -14.2 degrees (i.e., kyphosis) with an average postoperative correction of 27.9 degrees. Mean preoperative lumbar scoliosis measured 40.1 degrees with an average postoperative correction of 15.1 degrees. Mean preoperative plumb sagittal and coronal plane alignment was 8.37 cm and 4.22 cm, respectively; after surgery they improved to 3.33 cm and 2.31 cm, respectively. A significant association was found between sagittal angular correction and physical function (P = 0.034) and role-physical (P = 0.01) when postoperative lumbar lordosis was >25 degrees. A significant association was also found between plumb coronal correction and physical function (P = 0.041), vitality (P = 0.05), and social function (P = 0.047) when postoperative plumb coronal alignment was <2.5 cm. CONCLUSIONS: Correction of sagittal and coronal deformity is important in the treatment of spinal deformity. A significant association was found between outcomes and radiographic correction of coronal and/or sagittal deformity if postoperative sagittal lordosis was >25 degrees and if postoperative plumb coronal alignment was <2.5 cm. Therefore, these radiographic parameters should be the goal of a spinal osteotomy. The surgery has a relatively high complication rate.

Adult↗
PubMed2002

Dural ectasia and back pain: review of the literature and case report.

Dural ectasia is defined as a ballooning of the dural sac which is more common in patients with connective tissue disorders such as the Marfan syndrome. Several studies have shown that dural ectasia may be associated with such conditions as back pain, headaches, radiculopathies, or incontinence. We present a case of a 52 year old woman with Marfan syndrome who presented with a significantly large anterior sacral meningocele without having associated symptoms. In light of this case, we recommend that asymptomatic Marfan patients with dural ectasia should be closely observed without need for immediate surgical intervention.

Back Pain↗
PubMedDate not supplied

Plain radiography of the lumbosacral spine in Marfan syndrome.

BACKGROUND CONTEXT: Marfan syndrome is a connective tissue disorder that results from a defect in the production of fibrillin. These patients tend to have several osseous anomalies of the lumbosacral spine. PURPOSE: This study examines the effectiveness of plain radiographic findings in predicting Marfan syndrome. STUDY DESIGN/SETTING: Case-control study. PATIENT SAMPLE: Fourteen height-matched controls and 33 patients with Marfan syndrome were obtained from our genetics clinic or through the National Marfan Foundation. OUTCOME MEASURES: Determined using measurements taken on plain radiographs. METHODS: Five measurements were acquired of the lumbosacral spine from the radiographs of both groups: interpedicular distance, scalloping value, sagittal canal diameter, vertebral body width and transverse process width. RESULTS: The following measurements were significantly larger in patients with Marfan syndrome: interpedicular distance at L1-L5 (p<.0001); sagittal diameters of the vertebral canal at L4-S2 (p<.01); transverse process to vertebral body width ratio at L2-L5 (p<.01). There was no significant difference in the scalloping values from L1-L5 between the patients with Marfan syndrome and the controls. A multivariate regression analysis generated the following criteria for plain film diagnosis of Marfan syndrome (two criteria need to be met for diagnosis): interpedicular distance at L5 greater than or equal to 36.0 mm, sagittal diameter at L5 greater than or equal to 13.5 mm or transverse process to vertebral width ratio at L3 greater than or equal to 2.25. CONCLUSION: Based on this criteria, patients can be diagnosed with Marfan syndrome with a high sensitivity (81.8%) but a low specificity (58.3%). Thus, plain radiography can be a useful means of screening patients with Marfan syndrome.

Adult↗