Effect of BMI on the clinical outcome following microsurgical decompression in over-the-top technique: bi-centric study with an analysis of 744 patients.

PURPOSE: Decompression is one of the most common interventions in spinal surgery. Obesity has become an increasing issue in surgical patients. Therefore, the aim of this study was to analyze the clinical outcome following lumbar microsurgical decompression in correlation with the patient's body mass index (BMI). MATERIALS AND METHODS: A toal of 744 patients with spinal claudication that were seen at two specialized spine centers were included in this study. All patients underwent a bilateral microsurgical decompression in over-the-top technique. Patients were allocated in 4 groups based in their BMI category: 18.5-24.9 (n = 204), 25.0-29.9 (n = 318), 30.0-34.9 (n = 164) and ≥ 35 (n = 58). Clinical outcome data were recorded at baseline as well as 3, 12 and 24 months thereafter within a prospective study framework. The minimum follow-up was 12 months. For statistical analysis, data were adjusted for age, length of surgery and ASA and were analyzed by generalized linear gamma-based models. RESULTS: Postoperative changes in all outcome parameters were clearly dependent on BMI. Patients with higher BMI were characterized by inferior baseline values for VAS Back (p < 0.05). Over the follow-up period, the groups with BMI 30-34.9 and BMI ≥ 35 benefitted significantly less from the surgery than the two slimmer groups (p < 0.05). CONCLUSION: The data obtained from this large, homogenous cohort demonstrate that the quality of life improved substantially in all patients that were treated microsurgically for spinal stenosis. However, a BMI ≥ 30 may be considered as a negative predictor for a significantly inferior clinical outcome.

SPINE20 A global advocacy group promoting evidence-based spine care of value.

PURPOSE: The Global Burden of Diseases (GBD) Studies have estimated that low back pain is one of the costliest ailments worldwide. Subsequent to GBD publications, leadership of the four largest global spine societies agreed to form SPINE20. This article introduces the concept of SPINE20, the recommendations, and the future of this global advocacy group linked to G20 annual summits. METHODS: The founders of SPINE20 advocacy group coordinated with G20 Saudi Arabia to conduct the SPINE20 summit in 2020. The summit was intended to promote evidence-based recommendations to use the most reliable information from high-level research. Eight areas of importance to mitigate spine disorders were identified through a voting process of the participating societies. Twelve recommendations were discussed and vetted. RESULTS: The areas of immediate concern were "Aging spine," "Future of spine care," "Spinal cord injuries," "Children and adolescent spine," "Spine-related disability," "Spine Educational Standards," "Patient safety," and "Burden on economy." Twelve recommendations were created and endorsed by 31/33 spine societies and 2 journals globally during a vetted process through the SPINE20.org website and during the virtual inaugural meeting November 10-11, 2020 held from the G20 platform. CONCLUSIONS: This is the first time that international spine societies have joined to support actions to mitigate the burden of spine disorders across the globe. SPINE20 seeks to change awareness and treatment of spine pain by supporting local projects that implement value-based practices with healthcare policies that are culturally sensitive based on scientific evidence.

A retrospective analysis of bone mineral status in patients requiring spinal surgery.

BACKGROUND: Impaired bone quality is associated with poor outcome of spinal surgery. The aim of the study was to assess the bone mineral status of patients scheduled to undergo spinal surgery and to report frequencies of bone mineral disorders. METHODS: We retrospectively analyzed the bone mineral status of 144 patients requiring spinal surgery including bone mineral density by dual-energy X-ray absorptiometry (DXA) as well as laboratory data with serum levels of 25-hydroxyvitamin D (25-OH-D), parathyroid hormone, calcium, bone specific alkaline phosphate, osteocalcin, and gastrin. High-resolution peripheral quantitative computed tomography (HR-pQCT) was additionally performed in a subgroup of 67 patients with T-Score below - 1.5 or history of vertebral fracture. RESULTS: Among 144 patients, 126 patients (87.5%) were older than 60 years. Mean age was 70.1 years. 42 patients (29.1%) had suffered from a vertebral compression fracture. 12 previously undiagnosed vertebral deformities were detected in 12 patients by vertebral fracture assessment (VFA). Osteoporosis was present in 39 patients (27.1%) and osteopenia in 63 patients (43.8%). Only 16 patients (11.1%) had received anti-osteoporotic therapy, while 54 patients (37.5%) had an indication for specific anti-osteoporotic therapy but had not received it yet. The majority of patients had inadequate vitamin D status (73.6%) and 34.7% of patients showed secondary hyperparathyroidism as a sign for a significant disturbed calcium homeostasis. In a subgroup of 67 patients, severe vertebral deformities were associated with stronger deficits in bone microarchitecture at the distal radius compared to the distal tibia. CONCLUSIONS: This study shows that bone metabolism disorders are highly prevalent in elderly patients scheduled for spinal surgery. Vertebral deformities are associated with a predominant deterioration of bone microstructure at the distal radius. As impaired bone quality can compromise surgical outcome, we strongly recommend an evaluation of bone mineral status prior to operation and anti-osteoporotic therapy if necessary.

The effect of incidental dural lesions on outcome after decompression surgery for lumbar spinal stenosis: results of a multi-center study with 800 patients.

PURPOSE: Incidental durotomy is one of the most common complications in lumbar spine surgery. There are conflicting reports whether a dural lesion is associated with an inferior outcome after lumbar decompression. This study analyzed the effect of incidental durotomy in this specific group of patients (Dura+) and compared the results with the remaining cohort without dural laceration (Dura-). METHODS: This prospective multi-center study included 800 patients with lumbar spinal stenosis who underwent exclusive decompression surgery. All procedures were performed as part of a multi-center investigation at three highly specialized spine clinics. Outcome measures (ODI, EQ5D, VASback pain and VASleg pain) were obtained preoperatively as well as 3 and 12 months after surgery. The effect of an incidental durotomy on the clinical outcomes was analyzed statistically between the two cohorts. RESULTS: An intraoperative dura lesion was recorded in 6.5 % (n = 52/800) of all cases. Both cohorts (Dura+ and Dura-) did not reveal any differences regarding patient demographics, risk factors, or co-morbidities at baseline. The length of the hospital stay was significantly longer for the Dura+ cohort (8.0 vs. 6.4 days; p < 0.01). After 12 months, the Dura- cohort demonstrated a significantly greater improvement in VASback pain in comparison to the Dura+ cohort (Δ21.4 vs. Δ7.2 points; p < 0.05). The differences for the remaining outcome measures were not statistically significant (p > 0.05). CONCLUSIONS: The results of this study reveal that an incidental durotomy was associated with a significant increase in the patient's length of stay, and risk for re-intervention for the treatment of persisting CSF leakage. In contrast to previous reports which have investigated the effects of incidental durotomies on the clinical outcome after lumbar decompression surgery, our data further suggest a possible inferior outcome in terms of low back pain improvement in the Dura+ cohort, which became clinically apparent at the 12-month follow-up period. Future studies should investigate whether a more pronounced decompression required for adequate exposure and repair of a dural laceration may, ultimately, result in increased segmental instability and in clinically undesirable low back pain.

Clinical and radiological outcome at 10 years of follow-up after total cervical disc replacement.

PURPOSE: Previous studies have demonstrated that total cervical disc replacement (cTDR) represents a viable treatment alternative to the 'gold standard' anterior cervical discectomy and fusion for the treatment of well-defined cervical pathologies at short- and mid-term follow-up (FU). However, the implementation and acceptance of a non-fusion philosophy is closely associated with its avoidance of adjacent segment degeneration. Proof of the functional sustainability and clinical improvement of symptoms at long-term FU is still pending. The aim of this ongoing prospective study was to investigate the clinical and radiological results of cTDR at long-term FU. METHODS: 50 patients were treated surgically within a non-randomised prospective study framework with cTDR (ProDisc C™, Synthes, Paoli, PA, USA). Patients were examined preoperatively followed by routine clinical and radiological examinations at 1, 5 and 10 years after surgery, respectively. In addition to the clinical scores, conventional X-ray images of the cervical spine were taken in anteroposterior and lateral view as well as flexion/extension images. Clinical outcome scores included parameters such as the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires as well as subjective patient satisfaction rates. The radiological outcome variables included the range of motion (ROM) of the implanted prosthesis between maximum flexion and extension images, the occurrence of heterotopic ossifications and radiographic signs of adjacent segment degenerative changes. The reoperation rate following cTDR was recorded as a secondary outcome variable. RESULTS: A significant and maintained clinical improvement of all clinical outcome scores was observed after a mean FU of 10.2 years (VASarm 6.3-2.1; VASneck 6.4-1.9; NDI 21-6; p < 0.05). An increase in the incidence and the extent of heterotopic ossifications was noted during the post-operative course with a significant influence on the function of the prosthesis, which, however, did not reveal any detrimental effect on the patients' clinical symptomatology. Prosthesis mobility declined from 9.0° preoperatively and 9.1° at 1 year FU to 7.7° and 7.6° at the five- and ten-year FU examinations, respectively. Radiological signs of adjacent segment degeneration were detected in 13/38 (35.7%), however, in only 3/38 (7.9%) patients this radiological changes were associated with clinical symptoms requiring conservative treatment. Intraoperative technical failure in two cases required interbody fusion with a cage (2/50). One patient (1/48, 2.1%) treated this motion device had revision surgery at the index level. CONCLUSION: Cervical total disc replacement with ProDisc C demonstrated a significant and maintained improvement of all clinical outcome parameters at a follow-up of ≥10 years. The present long-term data reveal that with an exceptionally low implant-related reoperation rate and low symptomatic adjacent segment degeneration rate, cTDR may be regarded as a safe and viable treatment option.

Surgery for adult spondylolisthesis: a systematic review of the evidence.

Surgery for isthmic and degenerative spondylolisthesis (SL) in adults is carried out very frequently in everyday practice. However, it is still unclear whether the results of surgery are better than those of conservative treatment and whether decompression alone or instrumented fusion with decompression should be recommended. In addition, the role of reduction is unclear. Four clinically relevant key questions were addressed in this study: (1) Is surgery more successful than conservative treatment in relation to pain and function in adult patients with isthmic SL? (2) Is surgery more successful than conservative treatment in relation to pain and function in adult patients with degenerative SL? (3) Is instrumented fusion with decompression more successful in relation to pain and function than decompression alone in adult patients with degenerative SL and spinal canal stenosis? (4) Is instrumented fusion with reduction more successful in relation to pain and function than instrumented fusion without reduction in adult patients with isthmic or degenerative SL? A systematic PubMed search was carried out to identify randomized and nonrandomized controlled trials on these topics. Papers were analyzed systematically in a search for the best evidence. A total of 18 studies was identified and analyzed: two for question 1, eight for question 2, four for question 3, and four for question 4. Surgery appears to be better than conservative treatment in adults with isthmic SL (poor evidence) and also in adults with degenerative SL (good evidence). Instrumented fusion with decompression appears to be more successful than decompression alone in adults with degenerative SL and spinal stenosis (poor evidence). Reduction and instrumented fusion does not appear to be more successful than instrumented fusion without reduction in adults with isthmic or degenerative SL (moderate evidence).

Incidental durotomy in spine surgery: first aid in ten steps.

INTRODUCTION: Incidental durotomy (ID) is the most common complication of spine surgery. Revision procedures, ossification of the yellow ligament, or synovial cysts are well-known risk factors. The size, shape, and severity of ID are unpredictable, ranging from a pinpoint hole to a several centimeters large dural laceration with transected fibers following the slippage of a cutting burr. Furthermore, the occurrence of ID is always unexpected. Intra-operative management is often based on a steep learning curve rather than a structured scheme. PURPOSE: To provide an intra-operative ten-step closure technique (10ST) for IDs of varying severity. METHODS: A database of 4020 consecutive surgeries for lumbar degenerative disease over the past 4 years was searched for ID. The records of 176 patients were analyzed. Two dural repair techniques were compared: the "individual" technique (InT) and the 10ST. RESULTS: The overall prevalence of ID was 4.4%. The prevalence was lowest in virgin micro-discectomies (1.7%) and ranged from 3.6% in decompression for spinal canal stenosis up to 14.5% in revision procedures. All surgeries were performed with the aid of a microscope. Among 107 primary surgeries, the InT achieved a single-stage closure of the ID in 96 procedures (89.7%). Among 20 virgin surgeries, the 10ST was successful in all cases (P = 0.21). Among 42 re-do procedures following failed attempts to stop cerebrospinal fluid (CSF) leakage, the InT achieved single-stage closure in 36 procedures (85.7%). The 10ST was successful in all 26 cases (P = 0.03). The follow-up was 1 year. CONCLUSIONS: The 10ST should be considered for successful single-stage closure in primary repair of ID.

Do TLIF and PLIF Techniques Differ in Perioperative Complications? - Comparison of Complications Rates of Two High Volume Centers.

STUDY DESIGN: Retrospective bicentric Cohort Study. OBJECTIVE: Posterior (PLIF) and transforaminal lumbar interbody fusion (TLIF) have been clinically proven for the surgical treatment of degenerative spinal disorders. Despite many retrospective studies, the superiority of either technique has not been proven to date. In the literature, the complication rate of the conventional PLIF technique is reported to be significantly higher, but with inconsistent complication recording. In this retrospective bicentric study, a less invasive PLIF technique was compared with the conventional TLIF technique and complications were recorded using the validated SAVES V2 classification system. METHODS: 1142 patients underwent PLIF (702) or TLIF (n = 440) up to 3 levels in two specialized centers. Epidemiological data, intra- and postoperative complications during hospitalization and after discharge were analyzed according to SAVES V2. RESULTS: The overall complication rate was 13.74%. TLIF-patients had slightly significant more complications than PLIF-patients (TLIF = 16.6%/PLIF = 11.9%, P = .0338). Accordingly, complications during revision surgeries were more frequent in the first cohort (TLIF = 20.9%/PLIF = 12.6%; P = .03252). In primary interventions, the surgical technique did not correlate with the complication rate (TLIF = 12.4%/PLIF = 11.7%). There were no significant differences regarding severity of complications. CONCLUSIONS: An important component of this work is the complication recording according to a uniform classification system (SAVES V2). In contrast to previous literature, we could demonstrate that there is not a significant difference between the two surgical techniques.

[Intraoperative computed tomography-guided navigation for implant anchorage in spine surgery]. / Navigation mit intraoperativer Computertomographie zur Implantatverankerung in der spinalen Chirurgie.

OBJECTIVE: Improved accuracy of spinal instrumentation with the use of intraoperative CT (iCT). INDICATIONS: All types of posterior spinal instrumentation. CONTRAINDICATIONS: None. SURGICAL TECHNIQUE: After fixation of the spinal clamp, an intraoperative CT (iCT) is performed. The image data set can then be used for navigation of the spinal implants. The arrangement of the devices, positioning of the patient, and the exact fixation of the clamp depend on the operation technique and the anatomical region. A high level of standardization is necessary for clinical success. In general, the utilization of drill guides over the use of awls and Yamshidi needles is strongly recommended. Thereby the risk of segmental vertebral rotation, especially in multisegmental instrumentation, will be reduced. POSTOPERATIVE MANAGEMENT: The postoperative management depends on the type of surgery and is not influenced by the use of navigation with iCT. RESULTS: In our patient group of the first 200 surgeries with iCT (AIRO, Brainlab AG, Munich, Germany), we performed 34% cervical instrumentations, 31% percutaneous screw insertions, and 35% multisegmental open procedures including the sacrum or ilium. Two surgeries had to be converted to conventional technique due to technical problems. One misplaced S2/Ala/ilium screw had to be corrected in revision surgery. The infection rate was 2.5% and was not increased compared to conventional procedures. In the literature, a significant reduction of radiation exposure was shown, when iCT and navigation were used. Also, in longer surgical cases the operation time could be reduced. In comparison with 3D C­arm imaging, the image quality and screw accuracy is improved by iCT. Due to the possibility of 3D intraoperative implant control, the number of revision cases can be reduced.

[Transmuscular approach (XLIF technique) for anterior surgery of the lumbar spine]. / Transmuskulärer Psoas-Zugang zur vorderen Lendenwirbelsäule (XLIF-Technik).

OBJECTIVE: Anterior stabilization of the spine with a lateral approach to insert a large and broad cage creating a better bearing surface to restore or maintain the lumbar lordosis. INDICATIONS: Degenerative scoliosis as well as revision surgery for stenosis of the neuroforamen. Lumbar corpectomies between L2/3 and L4/5 can be approached as well. CONTRAINDICATIONS: The segment L5/S1 is not suitable for the transmuscular approach. Relative contraindications are previous retroperitoneal surgery and spondylolisthesis with sliding of more than 50% (> Meyerding 2) SURGICAL TECHNIQUE: We describe the transmuscular retroperitoneal approach to the lumbar segments which is called extreme lateral approach (XLIF). To protect the spinal nerves on the way through the psoas muscle, use of intraoperative triggered neuromonitoring is paramount. POSTOPERATIVE MANAGEMENT: Full mobilization directly after surgery is possible in most cases. Weight bearing should be restricted to 20 kg for 3 months after surgery. RESULTS: The transmuscular approach to the lumbar spine is a good alternative to reach the anterior part of the lumbar spine. Degenerative scoliosis as well as stenosis of the neuroforamen especially in revision surgery are good indications for this technique. Injuries of the spinal nerves range from 0.7 to 15%. Other complications are rare.

Surgical Treatment of Multilevel Degenerative Cervical Myelopathy: Open-Door Laminoplasty and Fixation via Unilateral Approach. A Feasibility Study.

OBJECTIVE: We compared open-door laminoplasty via a unilateral approach and additional unilateral lateral mass screw fixation (uLP) with laminectomy and bilateral lateral mass screw fixation (LC) in the surgical treatment of multilevel degenerative cervical myelopathy (mDCM). METHODS: A retrospective cohort analysis of 46 prospectively enrolled patients (23 uLP and 23 LC). The minimum follow-up was 1 year. Neck and arm pains were evaluated with visual analog scales and disability with the Neck Disability Index (NDI). Myelopathy was rated with the modified Japanese Orthopaedic Association (mJOA) score. Cervical sagittal parameters were measured on plain and functional X-ray films with a specific software. The statistical significance was set at p < 0.05. Fusion was defined as <2 degrees of intersegmental motion on flexion/extension radiographs. RESULTS: The two groups were similar in age and comorbidities. The mean operation time and the mean hospital stay were shorter in the uLP group (p = 0.015). The intraoperative blood loss did not exceed 200 mL in both groups. At follow-up, the groups showed comparable clinical outcome data. The sagittal profile did not deteriorate in either group. Fusion rates were 67% in the uLP group and 92% in the LC group. No infections occurred in either group. In the LC group, one patient developed a transient C5 palsy. Revision surgery was required for a malpositioned screw (LC) and for one implant failure (uLP). CONCLUSION: Laminoplasty and unilateral fixation via a unilateral approach achieved comparable clinical and radiologic results with laminectomy and bilateral fixation, despite a lower fusion rate. However, the surgical traumatization was less.

Degenerative Cervical Myelopathy: A 7-Letter Coding System That Supports Decision-Making for the Surgical Approach.

OBJECTIVE: To validate with a prospective study a decision-supporting coding system for the surgical approach for multilevel degenerative cervical myelopathy. METHODS: Ten cases were presented on an internet platform, including clinical and imaging data. A single-approach (G1), a choice between 2 (G2), or 3 approaches (G3) were options. Senior and junior spine surgeons analyzed 7 parameters: location and extension of the compression of the spinal cord, C-spine alignment and instability, general morbidity and bone diseases, and K-line and multilevel corpectomy. For each parameter, an anterior, posterior, or combined approach was suggested. The most frequent letter or the last letter (if C) of the resulting 7-letter code (7LC) suggested the surgical approach. Each surgeon performed 2 reads per case within 8 weeks. RESULTS: G1: Interrater reliability between junior surgeons improved from the first read (κ = 0.40) to the second (κ = 0.76, p < 0.001) but did not change between senior surgeons (κ = 0.85). The intrarater reliability was similar for junior (κ = 0.78) and senior (κ = 0.71) surgeons. G2: Junior/senior surgeons agreed completely (58%/62%), partially (24%/23%), or did not agree (18%/15%) with the 7LC choice. G3: junior/senior surgeons agreed completely (50%/50%) or partially (50%/50%) with the 7LC choice. CONCLUSION: The 7LC showed good overall reliability. Junior surgeons went through a learning curve and converged to senior surgeons in the second read. The 7LC helps less experienced surgeons to analyze, in a structured manner, the relevant clinical and imaging parameters influencing the choice of the surgical approach, rather than simply pointing out the only correct one.

Clinical and Radiological Outcome of a New Total Cervical Disc Replacement Design.

STUDY DESIGN: A nonrandomized, prospective, and single-center clinical trial of the ProDisc Vivo prosthesis. OBJECTIVE: The aim of this study was to investigate the clinical and radiological results of a refined total cervical disc replacement (cTDR), the ProDisc Vivo, with two years of follow-up (FU). The incidence of implant-related complications was recorded as a secondary outcome variable. SUMMARY OF BACKGROUND DATA: Previous generations of the ProDisc artificial cervical disc replacement generate high primary stability due to keel-based designs with opening of the anterior cortex during the implantation and subsequent high rates of heterotopic ossifications. METHODS: Clinical outcome scores included the Neck Disability Index (NDI), Visual Analogue Scale (VAS), arm and neck pain self-assessment questionnaires. The radiological outcome included the range of motion (ROM) and the occurrence of heterotopic ossifications. The incidence of implant-related complications with new implant design was recorded as a secondary outcome variable. RESULTS: A total of 55 patients received a single-level treatment with the ProDisc Vivo cTDR between C3/4 and C6/7, with a follow-up rate of 78%. The clinical outcome scores improved in all parameters significantly (P = 0.0001) (NDI: 68.3 → 17.4; VAS arm: 6.3 → 1.4; VAS neck: 4.9 → 1.6). The ROM of the index-segment did not show a significant change (P = 0.26) (7.9° → 9.2°). Heterotopic ossifications at the index segment was found as grade 0 in 58%, grade 1 in 22%, grade 2 in 10%, grade 3 (with functional impairment of the prosthesis) in 7%, and grade 4 in 3% of the cases. We observed three implant-related complications (5.5%), with two implant dislocations anteriorly and one low-grade infect. CONCLUSION: cTDR with ProDisc Vivo demonstrated a significant and sustained improvement of all clinical outcome parameters. A less invasive implantation mechanism with lower primary stability of the cTDR might be a reason for a higher dislocation rate than the keel-based previous generation ProDisc C. LEVEL OF EVIDENCE: 4.

Placebo effects of a sham opioid solution: a randomized controlled study in patients with chronic low back pain.

This study tested the experimental placebo effect in a group of chronic pain patients. Forty-eight patients having chronic back pain participated in a randomized clinical trial that tested the efficacy of a sham opioid solution (NaCl) compared with an alleged neutral, completely inactive solution (NaCl). We shaped the placebo effect by 2 interventions: verbal instruction and conditioning. The patients were either told that the "solution reduces pain and improves physical capacity" or the "solution is neutral, a placebo." Half of each group was additionally conditioned (coupling solution with reduced experimental pain), yielding 4 subgroups with 12 participants each. Outcome measures were as follows: the patients' clinical back pain ratings and acute pain ratings (both examined by numerical rating scale 0-10) and self-rated functional capacity (0%-100%; time required for the exercise). Expected pain relief before and after solution intake was also assessed. The inactive solution (NaCl), when presented as an effective treatment (sham "opioid" solution), induced placebo analgesia as evident in lower ratings of the patients' clinical back pain (F(3.12,144.21) = 25.05, P < 0.001), acute pain ratings (F(1.99,87.40) = 18.12, P < 0.01), and time needed to complete a series of daily activities exercises (F(1,44) = 8.51, P < 0.01) as well as increased functional capacity (F(1,44.00) = 19.42, P < 0.001). The 2 manipulations (instruction and conditioning) changed pain expectations, and they were maintained in both sham opioid groups. The results suggest that it may be clinically useful to explicitly integrate placebo analgesia responses into pain management.

Degenerative Spondylolisthesis Is Related to Multiparity and Hysterectomies in Older Women.

STUDY DESIGN: A case-control study. OBJECTIVE: To determine whether parity and abdominal surgeries are associated with degenerative spondylolisthesis (DS). SUMMARY OF BACKGROUND DATA: DS is considered to be a major cause of low back pain (LBP) in the older population, with greater prevalence of DS among women. Because LBP and impaired abdominal muscle function are common during pregnancy and post-partum, parity-related abdominal muscle deficiency, resulting in poor spinal mechanics, could be a factor in the development of DS in women. Indeed a relationship between the number of pregnancies and DS was reported in one study. METHODS: A total of 322 women between the ages of 40 and 80 (149 with DS and 173 controls) filled out a questionnaire providing information about their demographics, the number of full-term pregnancies, the number and types of abdominal surgeries (including cesarean section and hysterectomies), and age at menopause among other items. A binary logistic regression was used as a multivariate model to identify the variables associated with DS. RESULTS: Along with age and body mass index as covariates, the number of full-term pregnancies and the hysterectomy were significant predictors of DS. Other abdominal surgeries, cesarean section, or the number of years postmenopause were not significant predictors of DS in this regression model after adjusting for all other significant variables. CONCLUSION: Each full-term pregnancy seems to be associated with the 22% increase in odds of developing DS. Hysterectomy nearly doubles the odds of DS as compared to women who did not have hysterectomy. LEVEL OF EVIDENCE: 4.

[Is a reformation of the medical training worthwhile? The quality of the Hamburg curriculum under the old and the new board certification law]. / Lohnt sich eine Reform der klinischen Ausbildung? Die Qualität des Hamburger Curriculums unter der alten und der neuen Approbationsordnung im Vergleich.

This paper presents the results of the evaluation of a new undergraduate curriculum at the Medical Faculty of Hamburg University. This curriculum is based on the new law on medical board certification of 2002, and was tested for the first time in the summer term of 2004. The results were compared with those obtained under the previous law. The data show a substantial increase in student subjective learning effectiveness and satisfaction with the new program. The reasons discerned were the increased practice orientation of the program, the problem-oriented seminars, and the increased motivation of the teaching staff.

Unconditioned and conditioned muscular responses in patients with chronic back pain and chronic tension-type headaches and in healthy controls.

Muscular tension is assigned an important role in the development and maintenance of chronic pain syndromes. It is seen as a psychophysiological correlate of learned fear and avoidance behavior. Basic theoretical models emphasize classical conditioning of muscular responses as a mechanism of pain chronification. However, the empirical basis for this field is very small. Our aim was to investigate muscular factors in relation to unconditioned and conditioned pain stimuli. An experimental study was conducted using a differential classical conditioning paradigm with 18 patients with chronic back pain (BP) and tension-type headache (TTH), and 18 healthy controls (HC). A high-pitched sound served as the CS+, paired with an intracutaneous electric pain stimulus (US), while a neutral sound was used as the CS-. Simultaneously, integrated surface electromyograms (iEMGs) were recorded for seven muscle sites. Our hypothesis was that the pain patients would demonstrate enhanced conditionability. Baseline values between patients (TTH, BP) and HC showed no significant differences. Although the perception and pain thresholds were balanced, both patient groups revealed a higher number of significant muscular responses to the pain stimulus (UR) than the HC. All participants showed significant conditioned muscular responses, however, the patients displayed a higher number than the healthy controls. Furthermore a significant relation was found between muscular responses and the experience of pain 1day after the experiment. Muscular responses can be learned via classical conditioning. TTH and BP patients revealed a higher number of unconditioned and conditioned responses.

Lumbar spinal stenosis: prognostic factors for bilateral microsurgical decompression using a unilateral approach.

OBJECTIVE: We describe a prospective cohort study that investigated the effectiveness of microsurgical bilateral decompression using unilateral laminotomy for lumbar spinal stenosis and assessed the factors influencing the outcome. METHODS: A total of 165 consecutive patients underwent decompression for lumbar spinal stenosis. They were divided into 3 age groups: A (<65 years), B (65-75 years), and C (>75 years). Further classification was performed according to body mass index (BMI): BMI 1 (<26), BMI 2 (26-30), and BMI 3 (>30), anesthesiological risk factors (American Society of Anesthesiologists), and the number of levels decompressed. The outcome was monitored by an independent observer at 1 week, 3 months, and 1 year after surgery. The following parameters were evaluated: pain (visual analog scale and analgesic consumption), functional improvement (Neurogenic Claudication Outcome Score), and walking performance, defined as walking distance x speed (treadmill). RESULTS: One week after surgery, pain decreased in 85.9% of patients, and a comparison of the pre- and postoperative use of analgesics showed that 38% of nonopioid use and 74% of opioid use were discontinued, whereas nonsteroidal anti-inflammatory drug consumption increased 13%. One year after surgery, pain remained decreased in 83.9% of patients, Neurogenic Claudication Outcome Score increased in 90.3% of patients, and walking performance improved in 92.2% of patients. BMI greater than 30 was the only negative prognostic factor for pain reduction (P = 0.012) and Neurogenic Claudication Outcome Score improvement (P = 0.019). Surprisingly, patients who underwent multilevel decompression benefitted more from surgery than those who underwent single-level decompression. CONCLUSION: Microsurgical bilateral decompression using unilateral laminotomy is an effective surgical option for lumbar spinal stenosis, even in high-risk patients with multilevel stenosis.