- Email: [email protected]
3:59 26. A retrospective study examining five-year post-surgical outcomes of virgin discectomy patients
Proceedings of the NASS 20th Annual Meeting / The Spine Journal 5 (2005) 1S–189S computerized tomography images in the plane passing through the center of L3-L4 and L4-L5 pedicles on both right and left sides were obtained from the specimens. The cross-sectional areas of the intervertebral foramina at L34 and L45 were measured with the Aquarius Image software in CT. The images were then transferred to computer, and disc space narrowing of L34 and L45 levels with 1-mm incremental displacements was performed through Microsoft paint software. With the scale set the same as CT imaging software’s scale, the cross-sectional areas of the intervertebral foramina at L34 and L45 and residual cross-sectional foraminal areas following 1, 2, 3, 4, and 5 mm narrowing of the L34 and L45 disc space were measured with the NIH Image J software in computer. The mean and standard deviation values were calculated for all measured dimensions. Student’s t tests were used to detect statistical differences in the cross-sectional areas at different degrees of disc space narrowing. The confidence level for significance was p⬍.05. RESULTS: The mean normal cross-sectional areas of the intervertebral foramen were 179.26⫾31.00 mm2 for L3-4 level, 163.98⫾43.48 mm2 for L4-5 level. No significant difference was found between that measured on CT and the one on the computer (p⬎0.05). Compared with normal values of intervertebral foraminal areas, a decrease of about 8% of L34 and L45 intervertebral foraminal areas was found respectively with each 1 mm incremental disc space narrowing. There were statistically significant differences among the normal and residual cross-sectional foraminal areas following different degrees of disc space narrowing (p⬍.0001). CONCLUSIONS: There is a significant decrease in the size of neuroforamen following lumbar disc space narrowing. The size of the intervertebral foramen is directly related to the height of the disc space. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No conflicts. doi: 10.1016/j.spinee.2005.05.026 12:06 25. A prospective cohort analysis of adjacent vertebral body bone mineral density in lumbar surgery patients with or without instrumented posterolateral fusion: a 9 to 12 year follow-up Kern Singh, MD, Howard S. An, MD, Dino Samartzis, MD, Ahmad Nassr, Jason Provus, Margaret Hickey, Gunnar B.J. Andersson, MD, PhD; Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, USA BACKGROUND CONTEXT: No long-term prospective study has evaluated the effects of instrumented lumbar fusions on bone remodeling at adjacent vertebral levels. Several studies in animals and humans have reported a decrease in bone mineral density (BMD) at the adjacent level during the first 6 months after spinal fusion with a return to baseline at 1year follow-up in up to 60% of patients. PURPOSE: To determine by dual energy X-ray absorptiometry (DEXA) long-term BMD changes that occur at the adjacent three levels above an instrumented posterolateral lumbar fusion or an isolated laminotomy and lumbar discectomy. STUDY DESIGN/SETTING: A prospective, cohort study. PATIENT SAMPLE: A study of 11 patients who underwent either a posterior lumbar spinal fusion with instrumentation (n⫽7) or a lumbar laminotomy and discectomy alone (n⫽4). OUTCOME MEASURES: BMD measured quantitatively by DEXA evaluation. METHODS: DEXA was performed initially at a mean postoperative follow-up of 4.0 years (range, 2.3 to 5.5 years) and again at a mean of 10.8 years (range, 9.1 to 12.4 years). Eleven patients were divided into two groups: laminotomy and discectomy (n⫽4) and instrumented posterior spinal fusion (n⫽7). All patients underwent surgical procedures at the L4L5 or L5-S1 levels with DEXA analysis being performed on the adjacent three cephalad levels. The discectomy group (mean age, 57.8 years) underwent lumbar hemilaminotomy without fusion whereas the other group (mean age, 60 years) underwent pedicle-screw instrumentation and posterolateral lumbar fusion. Peripheral sites, including the femoral neck, were
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included in the DEXA analysis to normalize for individual differences in bone mineral metabolism. RESULTS: At the mean 10.8-year follow-up, the fusion group was noted to have at the adjacent level, two levels cephalad, and three levels cephalad normalized BMDs of 1.47, 1.39, and 1.27 respectively. A 14.8%, 10.8%, and 9.5% increase respectively in normalized BMD was observed when compared with the mean 4-year fusion values (p⬍.05). This increase was also noted on comparative T-score, Z-score, and absolute BMD values (p⬍.05). The discectomy group when evaluated revealed no statistically significant change from the mean 4 to 10.8-year follow-up (BMD, normalized BMD, T-score, Z-score). No statistically significant difference was noted in hip BMD at the mean 4-year and 10.8-year follow-up (1.05 vs. 1.03), suggesting that the effects were local. CONCLUSIONS: The local BMD adjacent to an instrumented lumbar fusion is increased at a mean of 10.8 years after surgery. There is a gradual decrease in BMD changes with increasing distance from the fusion level. Alterations in fusion site biomechanics and modulus mismatch between the host bone and the spinal instrumentation most likely result in chronic, localized bone remodeling with an increased BMD that decreases the greater the distance from the fusion mass. DISCLOSURES: FDA device/drug: dual energy X-ray absorptiometry. Status: Approved for this indication. FDA device/drug: pedicle-screw instrumentation. Status: Approved for this indication. CONFLICT OF INTEREST: No conflicts. doi: 10.1016/j.spinee.2005.05.027
Wednesday, September 28, 2005 3:59–4:42 PM Concurrent Session: Lumbar Disc 3:59 26. A retrospective study examining five-year post-surgical outcomes of virgin discectomy patients William Welch, MD1, Robert Gatchel, MD2*, Patricia Karausky, RN1, Harry Herkowitz, MD3, Dennis Maiman, MD4, Frank Phillips, MD5, F. Todd Wetzel, MD6, Eugene Carragee, MD7, Hallett Mathews, MD8; 1 University of Pittsburgh, Pittsburgh, PA, USA; 2Univ. Texas, Arlington, TX, USA; 3William Beaumont Hospital, Royal Oak, MI, USA; 4Medical College of Wisconsin, Meqon, WI, USA; 5Rush University Medical Center, Chicago, IL, USA; 6Department of Orthopaedic Surgery, Temple University, Philadelphia, PA, USA; 7Stanford University, Stanford, CA, USA; 8MidAtlantic Spine Specialists, Richmond, VA, USA BACKGROUND CONTEXT: There is little research assessing the longterm outcome of discectomy surgery. Thus, this protocol was developed to collect five-year post-surgical outcomes of virgin discectomy subjects. PURPOSE: To define clinical outcomes, including how lumbar spine surgery affected the subjects’ ability to manage everyday life at that time, whether treatment the subjects received was helpful or harmful, whether additional treatment or surgery was needed after the initial surgery (discectomy), general health questions about how the subjects are feeling now, and pain levels before and after surgery. STUDY DESIGN/SETTING: The design of this study involved questionnaires that were given to eligible subjects either by telephone or mail. PATIENT SAMPLE: This was a multicenter, retrospective study. Any subject, age 18 years or older, who had a virgin discectomy within the January 1997 to March 1999 time period was considered. The sample was taken from each participating physician’s patient base. OUTCOME MEASURES: The outcome measures included were: the SF12; the Pain and Disability Questionnaire (PDQ); Treatment Helpfulness Questionnaire items; and a survey evaluating current health care for back pain. METHODS: All data were subsequently pooled at one site for statistical analysis. Descriptive statistics (means and percentages) were computed
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Proceedings of the NASS 20th Annual Meeting / The Spine Journal 5 (2005) 1S–189S
for all outcome variables, and compared with normative data. Statistical analyses of the confidence intervals associated with the subject cohort versus the normative databases were also conducted. RESULTS: A total of 53 subjects were evaluated. Outcome scores of the questionnaires revealed that, in general, patients’ responses indicated that they felt well both mentally and physically, that there was a low level of pain and functional disability, and that they were satisfied with the outcome of their surgery. The SF-12 PCS, the overall physical component scale, was 42.47. The SF-12 overall mental component was also in the normal range at 53.47. (50 is average in a normal population.) The PDQ, a measurement of pain and disability, was 41.1. The PDQ measurement of psychosocial function was 21.1 (range of 0 indicating no problem, up to 150 the greatest severity). The Treatment Helpfulness Questionnaire was 49.8 (score of 50 indicates good overall satisfaction with the surgery). Analyses of confidence intervals revealed no significant differences between the subjects and normative database values for any of the questionaire data. Finally, the repeat surgery rate on the original site was only 9.8%. CONCLUSIONS: Because the lumbar discectomy has become one of the most common spinal surgical procedures performed in the U.S, we are compelled to determine the long-term effects of this treatment modality. In looking at patients who are 5 years past the procedure and determining their overall level of health and well-being, we can reveal treatment inadequacies that require correction and can help identify methods to improve clinical outcomes both immediately and on a long-range basis. The present results are the first to demonstrate positive 5-year outcomes on a number of important biopsychosocial variables. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No conflicts.
distance and leg raising test by monthly examinations. The radiographic examinations were performed every 3 years after treatment. Statistical analysis was performed with chi-square test. RESULTS: In patients who underwent surgery, low back pain and leg pain disappeared shortly after surgery. Only one patient who underwent surgery received second surgery due to persisting and/or recurring symptoms. Tight hamstrings persisted postoperatively even after low back pain and leg pain had disappeared. However, the symptoms gradually improved with regular stretching exercises and disappeared completely in all the patients between 3 months and 1 year after surgery. None of the patients who were followed up until adulthood suffered problems in daily life due to recurrence of tight hamstrings. Of the 20 patients who reached adulthood, 18 showed narrowing of the intervertebral space in the affected intervertebral disc. However, none of these patients manifested lesions or instability in the adjacent disc. In 9 out of 12 patients who underwent conservative treatment, low back pain and leg pain disappeared, but tight hamstrings persisted in 10 patients with the exception of two individuals. Adult patients with persisting tight hamstrings experienced problems in their movements in daily living, especially those related to anteflexion of the trunk. Of the 11 patients without surgery who reached adulthood, 6 showed narrowing of the intervertebral space in the affected intervertebral disc. CONCLUSIONS: Because conservative treatment often results in persistent tight hamstrings, it is important to eliminate the irritation of the nerve roots by surgery at an early stage. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No conflicts. doi: 10.1016/j.spinee.2005.05.029
doi: 10.1016/j.spinee.2005.05.028
4:05 27. Clinical course of tight hamstrings in children with lumbar disc herniation following surgical or nonsurgical treatments Shunji Matsunaga, MD, Yoshimi Nagatomo, MD, Takuya Yamamoto, MD, Kyoji Hayashi, MD, Kazunori Yone, MD, Setsuro Komiya, MD; Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan BACKGROUND CONTEXT: Lumbar disc herniation in children is characterized by the presence of tight hamstrings, which disturbs their physical activities. However, there are few reports on long-term observations of the clinical course of tight hamstrings following treatment of pediatric lumbar disc herniation. PURPOSE: This study examined whether or not tight hamstrings had improved in pediatric patients with lumbar disc herniation following surgical treatment, compared with patients who did not undergo surgery, to investigate the significance of surgery for tight hamstrings. STUDY DESIGN/SETTING: A controlled comparative study was performed prospectively. PATIENT SAMPLE: This study involved 37 patients who developed lumbar disc herniation under the age of 16 and who manifested tight hamstrings on initial examination. Twenty-five patients underwent Love’s discectomy. The mean postoperative follow-up period was 11 years and 5 months, ranging from 5 to 19 years, during which 23 patients reached adulthood. Twelve matched patients who exhibited same degree tight hamstrings were treated conservatively. The mean follow-up period of patients treated conservatively was 10 years and 9 months, ranging from 3 to 12 years, during which 11 patients reached adulthood. Patients of both group underwent streching exersise by the same protocol. OUTCOME MEASURES: Improvement of pain and tight hamstrings in patients with surgery was compared with patients without surgery. Disabilities in daily life of adulthood caused by tight hamstrings and changes of radiographic findings of lumbar spine were also reviewed. METHODS: Low back and leg pain was measured with a visual analogue scale. Tight hamstrings of the patients was measured with finger-floor
4:11 28. An RCT of Orthotrac vest unloading vs. EZ brace—one-year outcomes John Triano, DC, PhD1, Carolyn Rogers, MS2, Jennifer Diedrich, BS3, Celeste Gonzalez2, Stephen Hoschschuler, MD4; 1University of Texas at Arlington, Plano, TX, USA; 2Innovative Spinal Technologies, Plano, TX, USA; 3Innovative Spinal Technologies, TX, USA; 4Texas Back Institute, TX, USA BACKGROUND CONTEXT: Patients with discopathy have leg pain due to compression or chemical neuritis. Axial load causes reduction in canal cross-section. A load of 25–50% body weight longer than 5 min reduces area to ⬍100 mm2. A method that reduces axial load while weight bearing may provide symptomatic relief. PURPOSE: This study evaluated the results after 1 year from Orthotrac pneumatic vest (OPV) versus EZ form brace as an additional therapy in patients with discopathy and leg pain. Our hypothesis is that the OPV will result in greater pain relief and increased self-reported functionality than the EZ. STUDY DESIGN/SETTING: Prospective randomized clinical trial with follow-up at 6, 12, 26, and 52 weeks. PATIENT SAMPLE: Patients (93) with back pain failing 4 weeks of conservative care, confirmed discopathy, and radiating leg pain were solicited. Inclusion required ability to stand upright and have consistent relief lying down. Candidates (87) were initially evaluated. A subgroup (25) did not enter therapy because of intervening clinical improvement, travel distance or change in interest. Sixty-two were participants. OUTCOME MEASURES: Self-reported VAS and Oswestry (Osw) scores were primary outcomes. METHODS: Consenting patients received an OPV or EZ based on a prospective randomization scheme under separate security. Assessment was by independent evaluator at 6, 12, 26 and 52 weeks. Once randomized, the patient saw the principal investigator (PI), blind to assessment and outcomes, for fitting. Analysis was by repeated measures ANOVA. A secondary analysis of change scores between the initial and 52-week outcome was by unpaired t test. A logit model was created to define patient characteristics of successful outcome defined as improvement ⬎25% in VAS.
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included in the DEXA analysis to normalize for individual differences in bone mineral metabolism. RESULTS: At the mean 10.8-year follow-up, the fusion group was noted to have at the adjacent level, two levels cephalad, and three levels cephalad normalized BMDs of 1.47, 1.39, and 1.27 respectively. A 14.8%, 10.8%, and 9.5% increase respectively in normalized BMD was observed when compared with the mean 4-year fusion values (p⬍.05). This increase was also noted on comparative T-score, Z-score, and absolute BMD values (p⬍.05). The discectomy group when evaluated revealed no statistically significant change from the mean 4 to 10.8-year follow-up (BMD, normalized BMD, T-score, Z-score). No statistically significant difference was noted in hip BMD at the mean 4-year and 10.8-year follow-up (1.05 vs. 1.03), suggesting that the effects were local. CONCLUSIONS: The local BMD adjacent to an instrumented lumbar fusion is increased at a mean of 10.8 years after surgery. There is a gradual decrease in BMD changes with increasing distance from the fusion level. Alterations in fusion site biomechanics and modulus mismatch between the host bone and the spinal instrumentation most likely result in chronic, localized bone remodeling with an increased BMD that decreases the greater the distance from the fusion mass. DISCLOSURES: FDA device/drug: dual energy X-ray absorptiometry. Status: Approved for this indication. FDA device/drug: pedicle-screw instrumentation. Status: Approved for this indication. CONFLICT OF INTEREST: No conflicts. doi: 10.1016/j.spinee.2005.05.027
Wednesday, September 28, 2005 3:59–4:42 PM Concurrent Session: Lumbar Disc 3:59 26. A retrospective study examining five-year post-surgical outcomes of virgin discectomy patients William Welch, MD1, Robert Gatchel, MD2*, Patricia Karausky, RN1, Harry Herkowitz, MD3, Dennis Maiman, MD4, Frank Phillips, MD5, F. Todd Wetzel, MD6, Eugene Carragee, MD7, Hallett Mathews, MD8; 1 University of Pittsburgh, Pittsburgh, PA, USA; 2Univ. Texas, Arlington, TX, USA; 3William Beaumont Hospital, Royal Oak, MI, USA; 4Medical College of Wisconsin, Meqon, WI, USA; 5Rush University Medical Center, Chicago, IL, USA; 6Department of Orthopaedic Surgery, Temple University, Philadelphia, PA, USA; 7Stanford University, Stanford, CA, USA; 8MidAtlantic Spine Specialists, Richmond, VA, USA BACKGROUND CONTEXT: There is little research assessing the longterm outcome of discectomy surgery. Thus, this protocol was developed to collect five-year post-surgical outcomes of virgin discectomy subjects. PURPOSE: To define clinical outcomes, including how lumbar spine surgery affected the subjects’ ability to manage everyday life at that time, whether treatment the subjects received was helpful or harmful, whether additional treatment or surgery was needed after the initial surgery (discectomy), general health questions about how the subjects are feeling now, and pain levels before and after surgery. STUDY DESIGN/SETTING: The design of this study involved questionnaires that were given to eligible subjects either by telephone or mail. PATIENT SAMPLE: This was a multicenter, retrospective study. Any subject, age 18 years or older, who had a virgin discectomy within the January 1997 to March 1999 time period was considered. The sample was taken from each participating physician’s patient base. OUTCOME MEASURES: The outcome measures included were: the SF12; the Pain and Disability Questionnaire (PDQ); Treatment Helpfulness Questionnaire items; and a survey evaluating current health care for back pain. METHODS: All data were subsequently pooled at one site for statistical analysis. Descriptive statistics (means and percentages) were computed
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Proceedings of the NASS 20th Annual Meeting / The Spine Journal 5 (2005) 1S–189S
for all outcome variables, and compared with normative data. Statistical analyses of the confidence intervals associated with the subject cohort versus the normative databases were also conducted. RESULTS: A total of 53 subjects were evaluated. Outcome scores of the questionnaires revealed that, in general, patients’ responses indicated that they felt well both mentally and physically, that there was a low level of pain and functional disability, and that they were satisfied with the outcome of their surgery. The SF-12 PCS, the overall physical component scale, was 42.47. The SF-12 overall mental component was also in the normal range at 53.47. (50 is average in a normal population.) The PDQ, a measurement of pain and disability, was 41.1. The PDQ measurement of psychosocial function was 21.1 (range of 0 indicating no problem, up to 150 the greatest severity). The Treatment Helpfulness Questionnaire was 49.8 (score of 50 indicates good overall satisfaction with the surgery). Analyses of confidence intervals revealed no significant differences between the subjects and normative database values for any of the questionaire data. Finally, the repeat surgery rate on the original site was only 9.8%. CONCLUSIONS: Because the lumbar discectomy has become one of the most common spinal surgical procedures performed in the U.S, we are compelled to determine the long-term effects of this treatment modality. In looking at patients who are 5 years past the procedure and determining their overall level of health and well-being, we can reveal treatment inadequacies that require correction and can help identify methods to improve clinical outcomes both immediately and on a long-range basis. The present results are the first to demonstrate positive 5-year outcomes on a number of important biopsychosocial variables. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No conflicts.
distance and leg raising test by monthly examinations. The radiographic examinations were performed every 3 years after treatment. Statistical analysis was performed with chi-square test. RESULTS: In patients who underwent surgery, low back pain and leg pain disappeared shortly after surgery. Only one patient who underwent surgery received second surgery due to persisting and/or recurring symptoms. Tight hamstrings persisted postoperatively even after low back pain and leg pain had disappeared. However, the symptoms gradually improved with regular stretching exercises and disappeared completely in all the patients between 3 months and 1 year after surgery. None of the patients who were followed up until adulthood suffered problems in daily life due to recurrence of tight hamstrings. Of the 20 patients who reached adulthood, 18 showed narrowing of the intervertebral space in the affected intervertebral disc. However, none of these patients manifested lesions or instability in the adjacent disc. In 9 out of 12 patients who underwent conservative treatment, low back pain and leg pain disappeared, but tight hamstrings persisted in 10 patients with the exception of two individuals. Adult patients with persisting tight hamstrings experienced problems in their movements in daily living, especially those related to anteflexion of the trunk. Of the 11 patients without surgery who reached adulthood, 6 showed narrowing of the intervertebral space in the affected intervertebral disc. CONCLUSIONS: Because conservative treatment often results in persistent tight hamstrings, it is important to eliminate the irritation of the nerve roots by surgery at an early stage. DISCLOSURES: No disclosures. CONFLICT OF INTEREST: No conflicts. doi: 10.1016/j.spinee.2005.05.029
doi: 10.1016/j.spinee.2005.05.028
4:05 27. Clinical course of tight hamstrings in children with lumbar disc herniation following surgical or nonsurgical treatments Shunji Matsunaga, MD, Yoshimi Nagatomo, MD, Takuya Yamamoto, MD, Kyoji Hayashi, MD, Kazunori Yone, MD, Setsuro Komiya, MD; Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan BACKGROUND CONTEXT: Lumbar disc herniation in children is characterized by the presence of tight hamstrings, which disturbs their physical activities. However, there are few reports on long-term observations of the clinical course of tight hamstrings following treatment of pediatric lumbar disc herniation. PURPOSE: This study examined whether or not tight hamstrings had improved in pediatric patients with lumbar disc herniation following surgical treatment, compared with patients who did not undergo surgery, to investigate the significance of surgery for tight hamstrings. STUDY DESIGN/SETTING: A controlled comparative study was performed prospectively. PATIENT SAMPLE: This study involved 37 patients who developed lumbar disc herniation under the age of 16 and who manifested tight hamstrings on initial examination. Twenty-five patients underwent Love’s discectomy. The mean postoperative follow-up period was 11 years and 5 months, ranging from 5 to 19 years, during which 23 patients reached adulthood. Twelve matched patients who exhibited same degree tight hamstrings were treated conservatively. The mean follow-up period of patients treated conservatively was 10 years and 9 months, ranging from 3 to 12 years, during which 11 patients reached adulthood. Patients of both group underwent streching exersise by the same protocol. OUTCOME MEASURES: Improvement of pain and tight hamstrings in patients with surgery was compared with patients without surgery. Disabilities in daily life of adulthood caused by tight hamstrings and changes of radiographic findings of lumbar spine were also reviewed. METHODS: Low back and leg pain was measured with a visual analogue scale. Tight hamstrings of the patients was measured with finger-floor
4:11 28. An RCT of Orthotrac vest unloading vs. EZ brace—one-year outcomes John Triano, DC, PhD1, Carolyn Rogers, MS2, Jennifer Diedrich, BS3, Celeste Gonzalez2, Stephen Hoschschuler, MD4; 1University of Texas at Arlington, Plano, TX, USA; 2Innovative Spinal Technologies, Plano, TX, USA; 3Innovative Spinal Technologies, TX, USA; 4Texas Back Institute, TX, USA BACKGROUND CONTEXT: Patients with discopathy have leg pain due to compression or chemical neuritis. Axial load causes reduction in canal cross-section. A load of 25–50% body weight longer than 5 min reduces area to ⬍100 mm2. A method that reduces axial load while weight bearing may provide symptomatic relief. PURPOSE: This study evaluated the results after 1 year from Orthotrac pneumatic vest (OPV) versus EZ form brace as an additional therapy in patients with discopathy and leg pain. Our hypothesis is that the OPV will result in greater pain relief and increased self-reported functionality than the EZ. STUDY DESIGN/SETTING: Prospective randomized clinical trial with follow-up at 6, 12, 26, and 52 weeks. PATIENT SAMPLE: Patients (93) with back pain failing 4 weeks of conservative care, confirmed discopathy, and radiating leg pain were solicited. Inclusion required ability to stand upright and have consistent relief lying down. Candidates (87) were initially evaluated. A subgroup (25) did not enter therapy because of intervening clinical improvement, travel distance or change in interest. Sixty-two were participants. OUTCOME MEASURES: Self-reported VAS and Oswestry (Osw) scores were primary outcomes. METHODS: Consenting patients received an OPV or EZ based on a prospective randomization scheme under separate security. Assessment was by independent evaluator at 6, 12, 26 and 52 weeks. Once randomized, the patient saw the principal investigator (PI), blind to assessment and outcomes, for fitting. Analysis was by repeated measures ANOVA. A secondary analysis of change scores between the initial and 52-week outcome was by unpaired t test. A logit model was created to define patient characteristics of successful outcome defined as improvement ⬎25% in VAS.