Uri M. Ahn

Dural ectasia in the Marfan syndrome: MR and CT findings and criteria

Purpose: To create criteria for detecting dural ectasia on MR or CT images in adult Marfan patients.Methods: Images were analyzed using a workstation. Parameters that predicted dural ectasia were included in our criteria.Results: Major criteria include: (1) width of dural sac below L5 > width above L4; (2) anterior sacral meningocele. Minor criteria include: (1) L5 nerve root sleeve diameter > 6.5 mm and (2) S1 scalloping > 3.5. Dural ectasia exists if 1 major or 2 minor criteria are present.Conclusion: MR and CT diagnose dural ectasia with high specificity and sensitivity. Our criteria accurately diagnose dural ectasia in adult Marfan patients.

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.

Cauda equina syndrome in ankylosing spondylitis (the CES-AS syndrome) : Meta-analysis of outcomes after medical and surgical treatments

The cauda equina syndrome in ankylosing spondylitis (the CES-AS syndrome) is marked by slow, insidious progression and a high incidence of dural ectasia in the lumbosacral spine. A high index of suspicion for this problem must be maintained when evaluating the patient with ankylosing spondylitis with a history of incontinence and neurologic deficit on examination. There has been disagreement in the literature as to whether surgical treatment is warranted for this condition. A meta-analysis was thus performed comparing outcomes with treatment regimens. Our results suggest that leaving these patients untreated or treating with steroids alone is inappropriate. Nonsteroidal antiinflammatory drugs may improve back pain but do not improve neurologic deficit. Surgical treatment of the dural ectasia, either by lumboperitoneal shunting or laminectomy, may improve neurologic dysfunction or halt the progression of neurologic deficit.

Osseous anatomy of the lumbosacral spine in Marfan syndrome.

Study Design. This study examines pedicle widths, laminar thicknesses, and scalloping values for lumbosacral spine elements in Marfan volunteers. Comparisons were made between these measurements and norms as well as measurements between Marfan patients with and without dural ectasia. Objectives. To determine if the lumbosacral vertebral elements are altered in the patient with Marfan syndrome. Summary of Background Data. Several abnormalities have been noted in Marfan lumbar spine, including pedicular attenuation and widened interpediculate distances. This may be due to abnormalities of growth or presence of dural ectasia. Given the large numbers of Marfan patients requiring spinal surgery and the high postoperative failure rate, better understanding of the bony anatomy of Marfan lumbar spine is necessary, especially if use of instrumentation is anticipated. Methods. Thirty-two volunteers with Marfan syndrome based on the Ghent criteria underwent spiral computed tomography of the lumbosacral spine. Images were evaluated for dural ectasia, and measurements of pedicle width, laminar thickness, and vertebral scalloping were made. Results. Pedicle widths and laminar thicknesses were significantly smaller in Marfan patients at all levels (P < 0.001). Mean pedicle widths at L1–L3 were smaller than the smallest available pedicle screw (5 mm). In Marfan patients with dural ectasia, laminar thickness from L5–S2 and pedicle widths at all lumbar levels were significantly reduced (P < 0.01). Vertebral scalloping at S1 was significantly greater in Marfan patients with dural ectasia (P = 0.02). Conclusion. Lumbar pedicle width and laminar thickness are significantly reduced in Marfan individuals. Those with dural ectasia demonstrate increased bony erosion of anterior and posterior elements of lumbosacral spine. Preoperative planning and routine computed tomography scans are recommended when operating on Marfan lumbosacral spine.

MECHANICAL NECK PAIN ANDCERVICOGENIC 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.

Thoracolumbar Spinal Abnormalities in Stickler Syndrome

Study Design Retrospective review of clinical and radiographic records of patients with Stickler syndrome. Objectives To describe thoracolumbar spinal abnormalities and their correlation with age and back pain among patients with Stickler syndrome. Summary of Background Data Stickler syndrome (hereditary arthro-ophthalmopathy) is an autosomal dominant connective tissue disorder characterized by skeletal, ocular, oral–facial, cardiac, and auditory manifestations. Prevalence is approximately 1 in 10,000 (similar to that of Marfan syndrome). No one has investigated spinal abnormalities in a large series of patients. Methods A single-center evaluation of 53 patients from 24 families with Stickler syndrome (age range, 1–70 years) in a multidisciplinary genetics clinic. Thoracolumbar radiographs were analyzed for spinal abnormalities and correlation with age and back pain. Results Thirty-four percent of patients had scoliosis, 74% endplate abnormalities, 64% Schmorl’s nodes, 43% platyspondylia, and 43% Scheuermann-like kyphosis. Sixty-seven percent of patients and 85% of adults reported chronic back pain. Endplate abnormalities and Schmorl’s nodes were associated with adult age; endplate abnormalities, Schmorl’s nodes, and adult age were associated with back pain. Only one adult patient was free of spinal abnormalities. Conclusions Spinal abnormalities are nearly uniformly observed in Stickler syndrome, progress with age, and are associated with back pain. Although common, scoliosis is generally self-limited (only one patient needed surgical treatment). Correct diagnosis of this syndrome facilitates early identification and management of other potentially severe systemic manifestations and genetic counseling for affected families. Moreover, recognition of Stickler syndrome allows accurate prognosis for skeletal abnormalities and anticipation of potential surgical complications.

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.

Reherniation and Failure After Lumbar Discectomy: A Comparison of Fragment Excision Alone Versus Subtotal Discectomy

Study Design Retrospective review of 259 lumbar discectomies. Objective To compare rates of reoperation after subtotal discectomy versus established rates after fragment excision. Summary of Background Data Herniated nucleus pulposes (HNP) and annular morphology influence rates of reherniation after discectomy. Certain patterns are linked to reherniation rates exceeding 20%. Methods We retrospectively reviewed 259 single-level lumbar discectomies performed between 1980 and 2005. Mean follow-up was 60.9 months. In each case, annulotomy and subtotal discectomy was performed in addition to excision of disc fragments. HNP morphology was classified according to the 4-part system of Carragee (type 1: fragment/fissure; type 2: fragment/defect; type 3: fragment/contained; type 4: no fragment/contained). Fisher exact test was used to compare our proportion of patients with reherniation and/or reoperation to Caragees series in which only fragment excision was performed. Results Of 259 cases, 12 (4.5%) reoperations were performed. A significant difference in failure/reoperation rate was noted in type 2 herniations. There was a significantly lower rate of failure and reoperation for type 2 HNP after subtotal discectomy (3.4%) when compared with fragment excision alone (21.2%), P<0.003. Conclusions Subtotal discectomy is an acceptable technique that decreases reherniation after lumbar discectomy.

Dural ectasia and conventional radiography in the Marfan lumbosacral spine

Abstract Objective. To determine how well conventional radiographic findings can predict the presence of dural ectasia in Marfan patients. Design and patients. Twelve Marfan patients without dural ectasia and 21 Marfan patients with dural ectasia were included in the study. Five radiographic measurements were made of the lumbosacral spine: interpediculate distance, scalloping value, sagittal canal diameter, vertebral body width, and transverse process width. Results. The following measurements were significantly larger in patients with dural ectasia: interpediculate distances at L3–L4 levels (P<0.03); scalloping values at the L1 and L5 levels (P<0.05); sagittal diameters of the vertebral canal at L5–S1 (P<0.03); transverse process to width ratios at L2 (P<0.03). Criteria were developed for diagnosis of dural ectasia in Marfan patients. These included presence of one of the following: interpediculate distance at L4 >38.0 mm, sagittal diameter at S1 >18.0 mm, or scalloping value at L5 >5.5 mm. Conclusion. Dural ectasia in Marfan syndrome is commonly associated with several osseous changes that are observable on conventional radiographs of the lumbosacral spine. Conventional radiography can detect dural ectasia in patients with Marfan syndrome with a very high specificity (91.7%) but a low sensitivity (57.1%).

Review of Medicolegal Cases for Cauda Equina Syndrome: What Factors Lead to an Adverse Outcome for the Provider?

Cauda equina syndrome is 1 of a few true surgical emergencies involving the lumbar spine. Although treatment within 48 hours has been found to correlate with improved outcomes, recovery of bowel and bladder control does not always occur, and loss of these functions can be distressing to patients. An understanding of factors affecting the legal outcome can aid the clinician in determining risk management for medicolegal cases of cauda equina syndrome. This study is a retrospective analysis of medicolegal cases involving cauda equina syndrome. The LexisNexis Academic legal search database was used to obtain medicolegal cases of cauda equina syndrome to determine risk factors for adverse decisions for the provider. Outcomes data on trial verdicts were collected, as were associated penalties. Case data were also compiled on age, sex, initial presentation site, initial diagnosis, whether a rectal examination was performed, time to consultation with a specialist, time to completion of advanced imaging study, time to surgery, and neurosurgical vs orthopedic consultation. Based on our study of court cases involving cauda equina syndrome, a positive association was found between time to surgery >48 hours and an adverse decision (P<.05). The actual degree of functional loss did not appear to affect the verdicts. Because 26.7% of the cases involved an initial presentation that included loss of bowel or bladder control, this study emphasizes the importance of cautioning all patients with spinal complaints of the potential risk for cauda equina syndrome.