Twin Cities Spine Center

Minneapolis, MN, United States

Twin Cities Spine Center

Minneapolis, MN, United States
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Liu H.,Peking University | Ploumis A.,University of Ioannina | Schwender J.D.,Twin Cities Spine Center | Garvey T.A.,Twin Cities Spine Center
Journal of Spinal Disorders and Techniques | Year: 2012

STUDY DESIGN: Retrospective clinical cohort study. OBJECTIVE: To determine the efficacy of posterior lateral mass screw/rod fixation and fusion for the treatment of symptomatic pseudarthrosis of anterior cervical fusion. SUMMARY OF BACKGROUND DATA: Both anterior revision and posterior repair of cervical pseudarthrosis have been reported. To date, there is still debate in the literature as how the patient with symptomatic cervical pseudarthrosis should be addressed. METHODS: Thirty-eight consecutive patients with symptomatic anterior cervical pseudarthrosis were treated with posterior lateral mass screw/rod fixation and fusion. The average follow-up was 28 months (24 to 60 mo) and patients were assessed with clinical examination, questionnaires, flexion-extension lateral radiographs, and/or computed tomography scans. The clinical results were classified as excellent, good, fair, or poor, according to Zdeblick criteria. RESULTS: All patients achieved a solid radiographic fusion at the final follow-up. The result was excellent in 10 patients, good in 22, fair in 6, and poor in none. CONCLUSIONS: Patients with symptomatic cervical pseudarthrosis that develops after anterior cervical discectomy and fusion may be managed successfully with posterior lateral mass screw fixation and fusion. Copyright © 2012 by Lippincott Williams & Wilkins.

Pare P.E.,Medtronic | Chappuis J.L.,Spine Center Atlanta | Rampersaud R.,Toronto Western Hospital | Agarwala A.O.,Panorama Orthopedics and Spine Center | And 3 more authors.
Spine | Year: 2011

Study Design.: Comparative biomechanical study was conducted in osteoporotic human cadaveric spines. Objective.: Determine the influence of the volume of polymethyl methacrylate injected through a fenestrated pedicle screw on the pullout strength and on the ability to safely remove the implant. Summary of Background Data.: Pedicle screw fixation in the osteoporotic spine can be improved by the addition of bone cement. Various injection techniques have been used. While improvement has been shown for the pullout strength, the optimal volume of cement to inject has not been previously studied. Methods.: Seven osteoporotic spines were instrumented with a standard and a fenestrated pedicle screw augmented with polymethyl methacrylate at each level (T7-L5). Three volumes of bone cement were randomly injected and stratified to the thoracic (0.5 cc, 1.0 cc, and 1.5 cc) and lumbar spine (1.5 cc, 2.0 cc, and 2.5 cc). Axial pullout strength and removal torque of the pedicle screws were quantified. Results.: The pullout strength of the fenestrated screw was normalized with respect to its contralateral control. Student paired t tests were conducted and a statistically significant increase was noted for 1.0 cc (186 ± 45%) and 1.5 cc (158 ± 46%) in the thoracic spine and for 1.5 cc (264 ± 193%), 2.0 cc (221 ± 93%), and 2.5 cc (198 ± 42%) in the lumbar spine. There was no significant difference with higher volumes of cement. The median removal torque was 0.34 Nm for the standard and 1.83 Nm for the augmented screws. When the augmented implants were removed, the bone cement sheared completely off at the fenestrations in 15 of the 17 cases. Conclusion.: Significant increases in pullout strength can be accomplished by injecting a limited quantity of bone cement through a fenestrated screw while minimizing the risks associated with higher volume. The majority of implants were removed without damaging the vertebra as the bone cement sheared off at the fenestrations. Copyright © 2011 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.

Winter R.B.,Twin Cities Spine Center | Burger E.L.,University of Colorado at Denver
Spine | Year: 2012

STUDY DESIGN.: Case report. OBJECTIVE.: To demonstrate a 36-year follow-up of a rare operation. SUMMARY OF BACKGROUND DATA.: There have been no reports of follow-up of pediatric hemivertebra excision and fusion into midadult life. METHODS.: A chart and radiological review at 36 years after surgery. RESULTS.: The patient is alive and well and leading a normal life. Her Oswestry Disability Index is 0. Mild degenerative radiological signs are evident at the adjacent level above (T10-T12) and below (sacroiliac joints). CONCLUSION.: Early excision of the L5 hemivertebra would have been preferable, but the long-term results are good. © 2012, Lippincott Williams & Wilkins.

Transfeldt E.E.,Twin Cities Spine Center | Topp R.,Twin Cities Spine Center | Mehbod A.A.,Twin Cities Spine Center | Winter R.B.,Twin Cities Spine Center
Spine | Year: 2010

Study Design. A retrospective clinical cohort study at a single spine center of patients with degenerative scoliosis and radiculopathy severe enough to require surgery. Objective. To evaluate the functional outcomes of 3 surgeries for degenerative scoliosis with radiculopathy; decompression alone, decompression and limited fusion, and decompression and full curve fusion. Summary of Background Data. Although these 3 surgical treatments have all been described for this problem, there exists little information as to what outcomes to expect. Methods. The study cohort consisted of 85 patients who met the inclusion criteria of degenerative scoliosis and radiculopathy, who had undergone 1 of the above 3 surgeries, who had not had any previous lumbar spine surgery, who had a minimum follow-up of at least 2 years, and who had filled out preoperative and postoperative functional evaluation forms including SF-36, Oswestry Disability Index, Roland Morris Scores, and a satisfaction questionnaire. Logistic regression analysis was conducted to predict the likelihood of success as related to decompression alone of rotatory olisthetic segments, extent of fusion, and postoperative sagittal balance. Patient demographics including curve magnitude, operative blood loss, length of hospital stay, complications, and need for revision surgeries were analyzed. The patients having decompression alone had the highest mean age (76.4 years) compared to decompression and limited fusion (70.4), and decompression and full curve fusion (62.5). Results. Cobb scoliosis angles remained unchanged in the 2 groups not having full curve fusion, while the full curve fusion group changed from a mean 39° before surgery to 19° at follow-up. The complication rate was highest (56%) in the full fusion group, was 40% in the limited fusion group, and 10% in the decompression alone group. The overall SF-36 analysis showed significant improvement in bodily pain, social function, role emotional, mental health, and mental composite domains. Oswestry Disability Indexes improved significantly in the decompression alone and limited fusion groups, but not in the full fusion group. In contrast, the satisfaction questionnaire showed the highest success to be in the full-curve fusion group and the lowest in the decompression-only group.Regression analysis revealed that sacrum to curve apex fusions and positive postoperative sagittal imbalance were associated with poor outcomes. Conclusion. Both good and poor results were seen with each of the 3 procedures. © 2010, Lippincott Williams & Wilkins.

Study Design.: Case report with 40-year follow-up after definitive surgery. Objective.: To show that extensive spine fusion in a young child can control the curve and does not necessarily lead to early death. Summary of Background Data.: Recent efforts to avoid early spine fusion by using either progressive lengthening of spinal or rib cage implants are based on the theory that early spine fusion is deleterious and results in early death due to pulmonary compromise. Unfortunately, there is little to no documentation to support this theory. Methods.: This is a single case report of a child who at the age of 3 months had a 32° congenital thoracic congenital scoliosis with a unilateral unsegmented bar, concave fused ribs, and convex hemivertebrae. By age 2 years, the curve had progressed to 64°, so a posterior fusion was done from T5 to T12. By age 8 years, the curve had dramatically increased, and she was referred to the author. She underwent a double-wedge osteotomy, both anteriorly and posteriorly, plus anterior fusion T4-L3 and posterior fusion from T1 to L3. A halo cast was used for correction. Results.: At a 40-year follow-up after her definitive surgery at the age of 8 years, she is still alive and functioning well, although her vital capacity is poor. Conclusion.: Extensive thoracic spine fusion at an early age did not result in early death, but the patient is far from ideal. © 2012 Lippincott Williams & Wilkins.

Joglekar S.B.,Twin Cities Spine Center | Mehbod A.A.,Twin Cities Spine Center
Journal of Clinical Neurophysiology | Year: 2012

Pedicle screws have become the gold standard of spinal instrumentation over the past decade owing to their biomechanical superiority. Despite their advantages, pedicle screw instrumentation is potentially dangerous, and surgeons wish to improve accuracy of screw placement to avoid complications associated with screw misplacement. The anatomy of the pedicles is variable throughout the spine, and several landmarks and trajectories have been suggested to aid safe placement of pedicle screws in the spine. Several techniques such as X-ray and computed tomography scan imaging coupled with computer-aided navigation are available to improve accuracy of screw insertion. Intraoperative neuromonitoring with the help of triggered electromyographic recordings has evolved as an objective evidence of assessing pedicle breach and proximity of the screw to neural structures. While all imaging and electrophysiological modalities should be applied on an individualized basis, finally no adjunctive technique can fully replace the need for surgical expertise and experience. © 2012 by the American Clinical Neurophysiology Society.

Dykes D.C.,Twin Cities Spine Center | White III A.A.,Harvard University
Clinical Orthopaedics and Related Research | Year: 2011

Background: In its 2002 publication Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care, the Institute of Medicine reported American racial and ethnic minorities receive lower-quality health care than white Americans. Because caregiver bias may contribute to disparate health care, the Liaison Committee on Medical Education and the Accreditation Council for Graduate Medical Education have issued specific directives to address culturally competent care education. Questions/purposes: We discuss the general approaches to culturally competent care education, the tools used in evaluating such endeavors, and the impact of such endeavors on caregivers and/or the outcomes of therapeutic interventions from three perspectives: (1) Where are we now? (2) Where do we need to go? (3) How do we get there? Methods: We summarized information from (1) articles identified in a PubMed search of relevant terms and (2) the authors' experience in delivering, evaluating, and promoting culturally competent care education. Where are we now? Considerable variation exists in approaches to culturally competent care education; specific guidelines and valid evaluation methods are lacking; and while existing education programs may promote changes in providers' knowledge and attitudes, there is little empirical evidence that such efforts reduce indicators of disparate care. Where do we need to go? We must develop evidence-based educational strategies that produce changes in caregiver attitudes and behaviors and, ultimately, reduction in healthcare disparities. How do we get there? We must have ongoing dialog about, development in, and focused research on specific educational and evaluation methodologies, while simultaneously addressing the economic, political, practical, and social barriers to the delivery of culturally competent care education. © 2011 The Association of Bone and Joint Surgeons®.

Winter R.B.,Twin Cities Spine Center | Lonstein J.E.,Twin Cities Spine Center
Spine | Year: 2010

Study Design: Retrospective case series. Objective: To make clinicians aware of this unusual natural history. Summary of Background Data: Nonprogressive and progressive scolioses due to hemivertebrae have been abundantly documented in the literature. There has been no article describing spontaneous improvement. Two case reports have been described elsewhere in a general article on natural history. Methods: From a previous review of 1250 patients with congenital spine deformity of all types, 7 patients were identified with spontaneous improvement of their scoliosis due to a hemivertebra during growth. Results: The mean curve at start of observation was 31° (range: 24°-43°), and at the end of observation was 19° (range: 10°-30°). Six of the curves were at the thora-columbar region (T11-L2), and the other at T1. The average duration of follow-up was 9 years. Conclusion: Spontaneous curve improvement is rare, but possible. In view of the difficulty of prediction for curves due to a hemivertebra, careful observation with careful curve measurement is recommended. Inappropriate early, aggressive surgery should be avoided. © 2010, Lippincott Williams & Wilkins.

Study Design: Case report with very long-term follow-up. Objective: To demonstrate the lasting value of correction and stabilization with multiple anterior autogenous strut grafting. Summary of Background Data: Although anterior strut grafting has been shown to be ideal for neurofibromatosis kyphosis, there have been no reports as to whether the benefit is maintained or lost over many years. Methods: This is a single case report with very long-term follow-up. Results: This adult patient, operated in February 1982, has been followed for 28 years, and is doing very well in life, although her pulmonary capacity is compromised. Conclusion: Although patients with severe spine deformity because of neurofibromatosis tend to deteriorate with time, this patient demonstrates that with aggressive correction and fusion management, a long-term good quality of life can be achieved. © 2011 Lippincott Williams & Wilkins.

Hartin N.L.,Twin Cities Spine Center | Mehbod A.A.,Twin Cities Spine Center | Joglekar S.B.,Twin Cities Spine Center | Transfeldt E.E.,Twin Cities Spine Center
Spine | Year: 2013

STUDY DESIGN.: Retrospective cohort study. OBJECTIVE.: The fusion risk score (FRS) is introduced to assess baseline risk of spine fusion surgery preoperatively. An objective method of stratifying risk allows the surgeon to control risk through tailoring intervention and explain differences in complication profile in high-complexity practice. SUMMARY OF BACKGROUND DATA.: Research has identified an elevated risk of serious complications in performing spine fusion surgery in the elderly, yet the rate of such surgery continues to increase. A range of comorbidities and the surgical factors are demonstrated predictors of perioperative risk. METHODS.: Retrospective review was made of 364 consecutive fusion surgical procedures in patients older than 65 years in an 18-month period. Logistic regression analysis was performed to identify factors predictive for the occurrence of perioperative events. The predictive variables were incorporated in a weighted fashion into the FRS scaled from 1 to 20. Patient demographics and comorbidities were incorporated into the FRS patient score (maximum 10) and surgical approach, levels, and osteotomies into the FRS procedure score (maximum 10). RESULTS.: Multivariate analysis demonstrated chronic kidney disease (odds ratio [OR] = 5.3, 95% confidence interval [CI]: 1.5-18.6, P = 0.008), chronic obstructive pulmonary disease (OR = 5.3, 95% CI: 2.0-14.2, P < 0.001), ischemic heart disease (OR = 4.1, 95% CI: 2.0-8.4, P < 0.001), an open anterior approach (OR = 3.6, 95% CI: 1.4-9.3, P = 0.010), diabetes (OR = 3.0, 95% CI: 1.4-6.4, P = 0.004), previous spinal surgery at the same site (OR = 2.6, 95% CI: 1.3-4.9, P = 0.005), age (OR = 1.07, 95% CI: 1.01-1.13, P = 0.019), and the number of motion segments fused (P = 0.049) to be predictive of perioperative events. When applied, the FRS was highly predictive of perioperative events, intensive care unit admission, operative time, blood loss, and length of stay (all P < 0.0001). A score over threshold 9 carries a greater than 50% risk of perioperative events. CONCLUSION.: The FRS predicts the risk of complications after spine fusion surgery on the basis of patient and surgery characteristics. It also predicts the risk of intensive care unit admission and correlates with operative time, blood loss, and postoperative length of stay. By balancing the FRS procedure score to the individual FRS patient score, the surgeon can quantify and control perioperative risk. © 2013, Lippincott Williams & Wilkins.

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