Biomedical subjects

Stephen I Esses

Publications and source records attributed to Stephen I Esses.

14 recordsLinked to original sources

PubMed2006

Assessment of magnetic resonance imaging in the diagnosis of lumbar spine foraminal stenosis--a surgeon's perspective.

STUDY DESIGN: A 2-part cadaveric study. OBJECTIVES: Part 1: To assess the reliability of a semiquantitative classification system for grading lumbar spine foraminal stenosis and the variability in magnetic resonance imaging (MRI) examinations carried out in different institutions. Part 2: to assess the difference between the foraminal measurements carried out on MRI images and on cadaveric specimens. SUMMARY OF BACKGROUND DATA: There are limited data to suggest that MRI examinations are sensitive or specific for the diagnosis of lumbar spine foraminal stenosis. The effect of the variability in techniques, used by different imaging centers, is not well understood. METHODS: Three fresh, frozen human lumbar spines were examined with 3 different clinical MRI systems. Eight spine surgeons used the MRI images to grade the foramina, on the basis of a previously suggested semiquantitative classification. In addition, the dimensions of all foramina were measured using software available on each of the MRI systems. The dimensions of the specimens' foramina were then measured in situ, graded, and compared with the MRI measurements. RESULTS AND CONCLUSIONS: There was poor intraobserver agreement using the semiquantitative grading system. The parameters associated with the grade of stenosis assigned to the foramen were as follows: (1) the observer doing the grading, (2) the place it was imaged, and (3) the location of the foramen. There was poor correlation between measurements of the foramina carried out on MRI and the specimens.

Aged↗

PubMed2006

Low back pain: prediction of short-term outcome of facet joint injection with bone scintigraphy.

PURPOSE: To prospectively evaluate use of bone scintigraphy with single photon emission computed tomography (SPECT) for identification of patients with low back pain who would benefit from facet joint injections. MATERIALS AND METHODS: The protocol was reviewed and approved by the institutional review board. All patients provided informed consent. Forty-seven patients (23 men and 24 women) with low back pain, who were scheduled for facet joint injections, were prospectively enrolled and randomized into groups A and B (mean ages, 43.3 and 44.2 years, respectively) with a group A-group B ratio of 2:1. Group A patients underwent bone scintigraphy with SPECT prior to injection. Group A patients with bone scans positive for facet joint abnormalities received injections at the levels where abnormalities were identified on the scan (group A1). Group A patients with negative scans (group A2) received injections at the levels that were decided as in group B. Group B patients received injections at the levels indicated by the referring physician and did not undergo bone scintigraphy. All patients completed a pain and function questionnaire before injection and at 1, 3, and 6 months afterward. The change in the American Academy of Orthopaedic Surgeons pain scores after 1, 3, and 6 months compared with baseline scores was analyzed with analysis of variance and post hoc Bonferroni multiple-comparison tests between groups. Cost analysis was performed. RESULTS: The change in the pain score at 1 month was significantly higher (P < .004) in group A1 than it was in the other two groups. In group A1, 13 of 15 patients had improvement in pain score of greater than 1 standard deviation at 1 month, whereas improvement occurred in only two of 16 patients in group A2 and five of 16 patients in group B. In patients with positive scans, the number of facets treated with injection was decreased from 60, which was the number originally indicated by the referring physician, to 27. The Medicare cost was reduced from $2191 per patient to $1865 with the use of SPECT. CONCLUSION: Bone scintigraphy with SPECT can help identify patients with low back pain who would benefit from facet joint injections.

Adult↗

PubMed2004

Changes in segmental intervertebral motion adjacent to cervical arthrodesis: a prospective study.

STUDY DESIGN: Prospective, observational. OBJECTIVES: Quantify the changes in intervertebral motion adjacent to cervical arthrodesis over time. SUMMARY OF BACKGROUND DATA: One of the frequently acknowledged sequelae following anterior cervical fusion is the development of adjacent segment disease. It has been argued that a spine fusion transfers stress to adjacent levels and results in increased compensatory motion. However, there are conflicting reports as to whether this actually occurs, and most of these are in vitro or retrospective clinical studies. METHODS: Patients undergoing anterior cervical discectomy and fusion underwent a preoperative dynamic fluoroscopic study, followed by imaging at regular intervals after surgery. Imaging data were analyzed by a validated software system. Relative motion between adjacent vertebrae was then calculated, and changes in motion cephalad to the fusion followed over time. RESULTS: Twenty-one patients were analyzed. Mean follow-up was 13 months (10-22 months). Intervertebral motion adjacent to the fusion changed by more than 4 degrees in 4 of the 21 patients. However, on average, there was no difference between preoperative and postoperative motion for shear, flexion-extension, or vertical displacement at the anterior or posterior disc space. CONCLUSIONS: Although there was some individual variation, at a mean of 13 months following surgery, there was no significant change in the average junctional intervertebral motion. If fusion is going to affect adjacent motion, it appears that this does not consistently occur in the first 1 to 2 years following surgery. Additionally, there was no observable relationship between motion and development of degenerative changes during this time.

Cervical Vertebrae↗

PubMed2004

Surgical evaluation and management of symptomatic lumbosacral meningeal cysts.

Sacral meningeal cysts are a fairly common finding in the workup of sciatica. In most instances, a cyst causes no symptoms. Occasionally, a symptomatic sacral cyst may present with chronic low back pain (radiculopathy), sensory loss in sacral dermatomes, perineal pain, or bowel or bladder dysfunction. Compared with computed tomography, magnetic resonance imaging shows meningeal cysts more often and allows better localization of sacral cysts. In this article, we present clinical guidelines that may be used to distinguish symptomatic cysts from asymptomatic cysts. We conclude that surgical treatment of a symptomatic cyst may include laminectomy with fenestration and imbrication of the cyst--or percutaneous treatment methods. Surgery for sacral meningeal cysts can lead to successful improvement of pain and function in activities of daily living in more than 80% of cases.

Central Nervous System Cysts↗

PubMed2003

Physical characteristics of polyaxial-headed pedicle screws and biomechanical comparison of load with their failure.

STUDY DESIGN: Pedicle screw strength or load to failure was biomechanically evaluated, and the geometric characteristics of pedicle screw instrumentation systems were compared. OBJECTIVES: To compare the features of pedicle screw systems, and to demonstrate the failure point of the polyaxial pedicle screw head. SUMMARY OF BACKGROUND DATA: Many pedicle screw instrumentation systems are currently available to the spine surgeon. Each system has its unique characteristics. It is important for the surgeon to understand the differences in these pedicle screw systems. Pedicle screw load to failure has not been subjected to a comparison study. METHODS: The physical characteristics of each pedicle screw instrumentation system were determined. Features of rods, instruments, and pedicle screws were cataloged. Biomechanical testing of the pedicle screw construct was performed to determine the site and force of the load to failure. Nine pedicle screw systems were evaluated. Testing was performed with a pneumatic testing system under load control. Three polyaxial screws were used for each test at a load rate of 100 N/second. The load failure value was the force at which the pedicle screw or polyaxial head-screw interface initially deflected. RESULTS: Biomechanical testing demonstrated in all instances that the polyaxial head coupling to the screw was the first failure point. Although there have been subtle design differences in the instruments over time, the features of the pedicle screw instrument sets have become remarkably similar. CONCLUSIONS: Biomechanical pedicle screw load-to-failure data demonstrated that the polyaxial head coupling to the screw is the first to fail and may be a protective feature of the pedicle screw, preventing pedicle screw breakage. Knowing the physical characteristics of the available pedicle screw instrumentation systems may allow the choice of pedicle screw best suited for a given clinical situation.

Biomechanical Phenomena↗

PubMed2003

Management of chronic limb pain with spinal cord stimulation.

BACKGROUND: Spinal Cord Stimulation (SCS) is a treatment option for chronic pain patients. The most common indication for SCS is the failed back syndrome with leg pain. In the last decade, advances in our understanding of appropriate stimulation programming, lead placement and the physiology of SCS, have led to changes in multi-site stimulation, and stimulation with differing programs. In the past, low back, axial neuropathic type pain was not responsive to SCS. With dual electrode arrays, and dual stimulation with alternating programs of stimulation, steering of stimulation paresthesia, and versatile programmable stimulation parameters, SCS has become a more versatile form of analgesia. PURPOSE: To describe the current treatment rational for SCS and the results of that treatment. RESULTS: The SCS is most efficient in patients with neuropathic pain of the extremities and less efficacious in patients with axial pain. CONCLUSION: SCS is the most effective treatment for limb pain not amenable to surgical decompression. The success of SCS in this chronic pain group is 80% successful in treatment of leg pain, and much less effective in treatment of axial pain.

Journal Article↗

PubMed2002

Anterior locking screw plate fixation for cervical spondylosis.

Thirty consecutive patients with significant cervical spondylotic myelopathy or radiculopathy were treated with anterior decompression, autologous iliac crest graft, and titanium hollow screw plate (THSP). Eight patients had 1 previous surgery, and 1 patient had 2 previous surgeries. Satisfactory fixation was achieved intraoperatively in all instances. At time of final follow-up, graft incorporation was noted in all instances. There were 4 complications: 2 superficial infections, treated nonoperatively; 1 case of dysphagia, which resolved; and 1 case of spasmodic torticollis, which resolved. The THSP system allowed immediate stabilization of the involved cervical levels and facilitated reliable fusion.

Adult↗

PubMedDate not supplied

Spinal epidural lipomatosis: case reports, literature review and meta-analysis.

BACKGROUND CONTEXT: Symptomatic spinal epidural lipomatosis (SEL), a rare cause of spinal cord compression, has most often been associated with exogenous steroid use. PURPOSE: Identify four associations with SEL, correlate the associated groups with level of disease and compare treatment with outcome data in these groups. STUDY DESIGN/SETTING: Case reports of three patients and analysis of 104 cases from the literature. PATIENT SAMPLE: Three patients from the senior author's practice. OUTCOME MEASURES: Not applicable. METHODS: The authors report three new cases of SEL not associated with steroid use. They review all available English literature and present a table of all 104 reported cases. RESULTS: The clinical course of three new patients is reported. CONCLUSIONS: Associated conditions are exogenous steroid use, obesity, endogenous steroid excess, and some remain idiopathic. Although SEL is a rare condition, our review of the literature reveals many more reported cases than previously thought. With increased awareness of this condition and improved imaging techniques, further studies of this disease should be undertaken.

Adult↗

PubMedDate not supplied

Scheuermann kyphosis: long-term follow-up.

BACKGROUND CONTEXT: There is considerable controversy as to the optimal treatment of Scheuermann kyphosis. Proposed modalities have included exercise, bracing and surgery. PURPOSE: The purpose of this study was to document the functional capacity and radiographic findings in adults who have been previously treated for Scheuermann kyphosis. STUDY DESIGN: A cohort study of all patients with Scheuermann kyphosis treated in a single institution using three different treatment modalities: exercise and observation, Milwaukee bracing and surgical fusion using the Harrington Compression System. PATIENT SAMPLE: Sixty-three patients were evaluated at a mean of 14 years after treatment (10 to 28 years). OUTCOME MEASURES: Two different functional evaluation instruments were used. Radiographic evaluation was carried out in 38 patients (60%). METHODS: Patient interviews were conducted using a specially designed questionnaire. Patients were then asked to undergo standing radiographs. Patients were divided into groups depending on the location of their kyphosis and the manner in which they had been treated. Standard statistical analysis was then carried out. RESULTS: At time of follow-up evaluation there were no differences in marital status, general health, education level, work status, degree of pain and functional capacity between the various curve types, treatment modality and degree of curve. Patients treated by bracing or surgery did have improved self-image, which they attributed to their treatment. Patients with kyphotic curves exceeding 70 degrees at follow-up had an inferior functional result. At time of final follow-up there were no statistical differences in degree of kyphosis and mode of treatment. CONCLUSIONS: By carefully selecting the appropriate treatment for patients with Scheuermann kyphosis on the basis of the patient's age, spinal deformity and the severity of back pain, it is possible to achieve a similar functional result at long-term follow-up. Despite different treatment protocols, patients with Scheuermann kyphosis tend to achieve a similar functional result at long-term follow-up.

Adult↗

PubMedDate not supplied

Direct repair of spondylolytic defects in young competitive athletes.

BACKGROUND CONTEXT: Operative treatment of symptomatic spondylolysis is rare. A variety of surgeries have been described. In general, reported operative success rates are high, although in most studies the successful return to sport of the competitive athlete is not detailed. PURPOSE: To review outcome, specifically return to sport, in a group of competitive athletes after direct pars repair for symptomatic spondylolysis. STUDY DESIGN/SETTING: This was a retrospective case series of a single surgeon. PATIENT SAMPLE: Series of four athletes who underwent direct pars repair over an 18-month period. OUTCOME MEASURES: Return to their sport. METHODS: Chart review of all patients who had undergone a single-level pars repair over an 18-month period. All patients had normal discs above the level of the repair. Postoperative clinical course was determined for all patients. RESULTS: The patients participated in different sports. All were able to return to their presymptomatic level of activity with no restriction. One had periodic low back pain that required nonsteroidal anti-inflammatory medicine as needed. The others were entirely asymptomatic. CONCLUSIONS: This small series suggests that with specific inclusion criteria, a select group of motivated athletes can expect to return to their sport after direct pars repairs for symptomatic spondylolysis that has failed conservative treatment.

Adolescent↗

PubMedDate not supplied

Hip spine syndrome: management of coexisting radiculopathy and arthritis of the lower extremity.

BACKGROUND CONTEXT: Significant lumbar spinal stenosis and lower extremity arthritis may coexist in the elderly. This combination of lumbar stenosis with radiculopathy and lower extremity arthritis may lead to diagnostic uncertainty. PURPOSE: To describe the findings of hip spine syndrome, a constellation of symptoms with extensive overlap of radiculopathy and lower extremity arthritis. CONCLUSIONS: Evaluation of the patient with lower extremity pain in consideration for total joint arthroplasty should include functional inquiry of the spinal nerves. Diagnostic tests and injections may allow an informative weighting of the patient's symptoms, leading to a better understanding of the patient's pain syndrome. There is a group of patients who have a total hip arthroplasty and then develop or may continue to have pain of groin and buttock, secondary to sciatica of lumbar spinal stenosis. For the patient undergoing total hip arthroplasty with asymptomatic spinal stenosis, there may be increased neurological risk at surgery, related to the stenosis. The patient with both conditions may require surgical decompression of the lumbar stenosis as well as joint arthroplasty of the arthritic joint.

Arthritis↗

PubMedDate not supplied

Cervical plates: comparison of physical characteristics and in vitro pushout strength.

BACKGROUND CONTEXT: There are many cervical plates available to the spine surgeon today. A single plate design may not be appropriate for every clinical situation. It is important for the surgeon to understand the differences of these plating systems. Plate systems are known to fail by screw pullout from the bone, screw and plate breakage and a less frequent but clinically observed screw pushout from the plate. Pushout testing of the screws from the plate have not previously been subjected to study. PURPOSE: This compares the features of cervical plating systems and the strength of the locking mechanisms to allow the surgeon to make a knowledgeable choice of plating system. STUDY DESIGN: This is a review of descriptive geometric characteristics of cervical plate systems and a biomechanical evaluation of locking mechanism screw pushout strength. METHODS: Physical characteristics of each plate were determined. Features of plates and screws were cataloged. Each of the test plate systems had a different locking mechanism. Biomechanical testing of the locking mechanism-screw-plate constructs was performed to determine the pushout strength of the fixation screw from the plate-locking mechanism. RESULTS: Physical characteristics of the plating systems, including lengths, widths, shortest screw lengths and distance from edge of plate to nearest screw, were determined. Biomechanical testing showed significant differences in pushout strength, in part explained by the type of locking mechanism. CONCLUSIONS: Biomechanical screw pushout data demonstrate that a significant range of pushout strengths exist across the available cervical plate systems today. Knowing the physical characteristics of the cervical plating systems available may allow the selection of a plate best suited for a given clinical situation.

Biomechanical Phenomena↗

PubMedDate not supplied

Scoliosis associated with lumbar spondylolisthesis: a case presentation and review of the literature.

BACKGROUND CONTEXT: The association between scoliosis and spondylolisthesis is well documented, but criteria and methods for managing the deformity in patients with debilitating pain are not clear. PURPOSE: To describe correction of scoliosis by internal fixation of the spondylolisthesis. STUDY DESIGN: Case report of a patient with scoliosis developing in association with spondylolisthesis. METHODS: A 17-year-old female presented with a 6-month history of back and leg pain. No spinal curvature was noted in radiographs taken at the onset of symptoms. Significant curvature appeared during the 6-month history of pain in association with an L5-S1 spondylolisthesis. The spondylolisthesis was repaired with posterior pedicle screw instrumentation. RESULTS: The pain and the spinal curvature almost completely resolved after surgery, and the outcome remained excellent 14 months after surgery. CONCLUSION: In the properly diagnosed patient, surgical repair of the spondylolisthesis can relieve pain and correct spinal curvature.

Adolescent↗

PubMedDate not supplied

Coccygodynia: evaluation and management.

Coccygodynia is pain in the region of the coccyx. In most cases, abnormal mobility is seen on dynamic standing and seated radiographs, although the cause of pain is unknown in other patients. Bone scans and magnetic resonance imaging may show inflammation and edema, but neither technique is as accurate as dynamic radiography. Treatment for patients with severe pain should begin with injection of local anesthetic and corticosteroid into the painful segment. Coccygeal massage and stretching of the levator ani muscle can help. Coccygectomy is done only when nonsurgical treatment fails, which is infrequent. Coccygectomy usually is successful in carefully selected patients, with the best results in those with radiographically demonstrated abnormalities of coccygeal mobility.

Coccyx↗