Freehand Technique for Pedicle Screw Placement during Surgery for Adolescent Idiopathic Scoliosis Is Associated with Less Ionizing Radiation Compared to Intraoperative Navigation.

PURPOSE: We aim to compare radiation exposure and implant-related complications of the freehand (FH) technique versus intraoperative image-guided navigation (IN) for pedicle screw placement in adolescent idiopathic scoliosis (AIS) and estimate associated lifetime attributable cancer risks. METHODS: A retrospective analysis of prospectively collected data from 40 consecutive AIS patients treated with pedicle screw instrumentation using the FH technique was performed. The dose area product (DAP) and effective dose (ED) were calculated. Screw-related complications were analysed, and the age- and gender-specific lifetime attributable cancer risks were estimated. The results were compared to previously published data on IN used during surgery for AIS. RESULTS: There were no implant-related complications in our cohort. Implant density was 86.6%. The mean Cobb angle of the main curve was 75.2° (SD ± 17.7) preoperatively and 27.7° (SD ± 10.8) postoperatively. The mean ED of our cohort and published data for the FH technique was significantly lower compared to published data on the IN technique (p < 0.001). The risk for radiogenic cancer for our FH technique AIS cohort was 0.0014% for male patients and 0.0029% for female patients. Corresponding risks for IN were significantly higher (p < 0.001), ranging from 0.0071 to 0.124% and from 0.0144 to 0.253% for male and female patients, respectively. CONCLUSION: The routine use of intraoperative navigation in AIS surgery does not necessarily reduce implant-related complications but may increase radiation exposure to the patient.

Clinical and Radiological Outcome of Disc Arthroplasty for the Treatment of Cervical Spondylotic Myelopathy.

INTRODUCTION: The aim of this study is to evaluate the clinical and radiological results of cervical disc arthroplasty (CDA) in patients with cervical spondylotic myelopathy (CSM) using the CP ESP® disc prosthesis. MATERIALS AND METHODS: Prospectively collected data of 56 patients with CSM have been analyzed. The mean age at surgery was 35.6 years (range: 25-43 years). The mean follow-up was 28.2 months (range: 13-42 months). The range of motion (ROM) of the index segments, as well as upper and lower adjacent segments, was measured before surgery and at final follow-up. The C2-C7 sagittal vertical axis (SVA), C2-C7 cervical lordosis (CL), and T1 slope minus cervical lordosis (T1s-CL) were analyzed as well. Pain intensity was measured preoperatively and during follow-up using an 11-point numeric rating scale (NRS). Modified Japanese Orthopaedic Association (mJOA) score was assessed preoperatively and during follow-up for the clinical assessment of myelopathy. Surgical and implant-associated complications were analyzed as well. RESULTS: The NRS pain score improved from a mean of 7.4 (±1.1) preoperatively to a mean of 1.5 (±0.7) at last follow-up (p < 0.001). The mJOA score improved from a mean of 13.1 (±2.8) preoperatively to a mean of 14.8 (±2.3) at last follow-up (p < 0.001). The mean ROM of the index levels increased from 5.2° (±3.0) preoperatively to 7.3° (±3.2) at last follow-up (p < 0.05). Four patients developed heterotopic ossifications during follow-up. One patient developed permanent dysphonia. CONCLUSIONS: CDA showed good clinical and radiological outcome in this cohort of young patients. The motion of index segments could be preserved. CDA may be a viable treatment option in selected patients with CSM.

Minimally invasive lumbopelvic stabilization of sacral fragility fractures in immobilized geriatric patients: feasibility and early return to mobility.

INTRODUCTION: In an aging society, the incidence of sacral fragility fractures is increasing and diagnosis is often delayed. Immobilization has devastating consequences especially in elderly patients. Short-term mobilization of these patients is crucial. The aim of this study is to evaluate the early return to mobility of immobilized geriatric patients with sacral fragility fractures treated with minimally invasive lumbopelvic stabilization. METHODS: Retrospective analysis of thirteen consecutive patients (13 females) which could not be mobilized with conservative treatment, and thus were treated with minimally invasive lumbopelvic stabilization. Pain intensity measurement on an 11-point Numeric Rating Scale (NRS), Tinetti Mobility Test (TMT), and Timed Up and Go Test (TUGT) were performed preoperatively and 4 weeks postoperatively. Surgical and medical complications were analyzed. RESULTS: Mean age at surgery was 83.92 ± 6.27 years and mean ASA score was 2.77 ± 0.42. NRS improved from a mean of 7.18 ± 0.98 preoperatively to a mean of 2.45 ± 0.93 4 weeks postoperatively (Ρ < 0.001). TMT score improved from a mean of 4.15 ± 3.67 preoperatively to a mean of 16.39 ± 4.61 4 weeks postoperatively (Ρ < 0.001). Due to immobilization, patients were not able finish TUGT preoperatively. Four weeks postoperatively TUGT reached a mean of 31.1 ± 11.08 s. There were two surgical complications (one wound healing disorder, one rod dislocation) in two patients that required revision surgery. Two patients developed pneumonia postoperatively. CONCLUSIONS: Minimally invasive lumbopelvic stabilization of sacral fragility fractures is feasible in geriatric patients. Early mobilization of these patients is possible after surgery. The rate of complications is acceptable.

Anthropogenic nitrogen deposition alters growth responses of European beech (Fagus sylvativa L.) to climate change.

Global change affects the functioning of forest ecosystems and the services they provide, but little is known about the interactive effects of co-occurring global change drivers on important functions such as tree growth and vitality. In the present study we quantified the interactive (i.e. synergistic or antagonistic) effects of atmospheric nitrogen (N) deposition and climatic variables (temperature, precipitation) on tree growth (in terms of tree-ring width, TRW), taking forest ecosystems with European beech (Fagus sylvatica L.) as an example. We hypothesised that (i) N deposition and climatic variables can evoke non-additive responses of the radial increment of beech trees, and (ii) N loads have the potential to strengthen the trees' sensitivity to climate change. In young stands, we found a synergistic positive effect of N deposition and annual mean temperature on TRW, possibly linked to the alleviation of an N shortage in young stands. In mature stands, however, high N deposition significantly increased the trees' sensitivity to increasing annual mean temperatures (antagonistic effect on TRW), possibly due to increased fine root dieback, decreasing mycorrhizal colonization or shifts in biomass allocation patterns (aboveground vs. belowground). Accordingly, N deposition and climatic variables caused both synergistic and antagonistic effects on the radial increment of beech trees, depending on tree age and stand characteristics. Hence, the nature of interactions could mediate the long-term effects of global change drivers (including N deposition) on forest carbon sequestration. In conclusion, our findings illustrate that interaction processes between climatic variables and N deposition are complex and have the potential to impair growth and performance of European beech. This in turn emphasises the importance of multiple-factor studies to foster an integrated understanding and models aiming at improved projections of tree growth responses to co-occurring drivers of global change.

Biomechanical Effects of a Dynamic Topping off Instrumentation in a Long Rigid Pedicle Screw Construct.

STUDY DESIGN: Biomechanical ex vivo study. OBJECTIVE: To determine if topping off instrumentation can reduce the hypermobility in the adjacent segments when compared with the classic rigid spinal instrumentation. SUMMARY OF THE BACKGROUND DATA: Long rigid instrumentation might increase the mechanical load in the adjacent segments, the resulting hypermobility, and the risk for adjacent segment disease. Topping off instrumentation intends to reduce the hypermobility at the adjacent level by more evenly distributing segmental motion and, thereby, potentially mitigating adjacent level disease. MATERIALS AND METHODS: Eight human spines (Th12-L5) were divided into 2 groups. In the rigid group, a 3-segment metal rod instrumentation (L2-L5) was performed. The hybrid group included a 2-segment metal rod instrumentation (L3-L5) with a dynamic topping off instrumentation (L2-L3). Each specimen was tested consecutively in 3 different configurations: native (N=8), 2-segment rod instrumentation (L3-L5, N=8), 3-segment instrumentation (rigid: N=4, hybrid: N=4). For each configuration the range of motion (ROM) of the whole spine and each level was measured by a motion capture system during 5 cycles of extension-flexion (angle controlled to ±5 degrees, 0.1 Hz frequency, no preload). RESULTS: In comparison with the intact spine, both the rigid 3-segment instrumentation and the hybrid instrumentation significantly reduced the ROM in the instrumented segments (L2-L5) while increasing the movement in the adjacent segment L1-L2 (P=0.002, η=0.82) and in Th12-L1 (P<0.001, η=0.90). There were no ROM differences between the rigid and hybrid instrumentation in all segments. CONCLUSIONS: Introducing the dynamic topping off did not impart any significant difference in the segmental motion when compared with the rigid instrumentation. Therefore, the current biomechanical study could not show a benefit of using this specific topping off instrumentation to solve the problem of adjacent segment disease.

Hybrid Instrumentation in Lumbar Spinal Fusion: A Biomechanical Evaluation of Three Different Instrumentation Techniques.

STUDY DESIGN: Ex vivo human cadaveric study. OBJECTIVE: The development or progression of adjacent segment disease (ASD) after spine stabilization and fusion is a major problem in spine surgery. Apart from optimal balancing of the sagittal profile, dynamic instrumentation is often suggested to prevent or impede ASD. Hybrid instrumentation is used to gain stabilization while allowing motion to avoid hypermobility in the adjacent segment. In this biomechanical study, the effects of two different hybrid instrumentations on human cadaver spines were evaluated and compared with a rigid instrumentation. METHODS: Eighteen human cadaver spines (T11-L5) were subdivided into three groups: rigid, dynamic, and hook comprising six spines each. Clinical parameters and initial mechanical characteristics were consistent among groups. All specimens received rigid fixation from L3-L5 followed by application of a free bending load of extension and flexion. The range of motion (ROM) for every segment was evaluated. For the rigid group, further rigid fixation from L1-L5 was applied. A dynamic Elaspine system (Spinelab AG, Winterthur, Switzerland) was applied from L1 to L3 for the dynamic group, and the hook group was instrumented with additional laminar hooks at L1-L3. ROM was then evaluated again. RESULTS: There was no significant difference in ROM among the three instrumentation techniques. CONCLUSION: Based on this data, the intended advantage of a hybrid or dynamic instrumentation might not be achieved.

Radiation-Induced Intraspinal Chondrosarcoma: A Case Report.

Study Design Case report and review of the literature. Objective To report a unique case of an intraspinal chondrosarcoma that was diagnosed 18 years after radiotherapy for a cervical carcinoma and its remarkably unusual clinical presentation. Methods A retrospective case description of an intraspinal mass lesion that occurred 6 weeks after previous spinal surgery. Results Within ∼9 weeks, the tumor had infiltrated the peritoneal cavity and reached the lumbar subcutaneous tissue. Conclusion Radiation-induced sarcomas are rare, are highly aggressive, and may be difficult to diagnose. Furthermore, the only means of achieving long-term survival is through early and extensive surgery.

Spine radiography in the evaluation of back and neck pain in an orthopaedic emergency clinic.

BACKGROUND AND OBJECTIVES: Despite the recommendations of national and international societies for the treatment of patients with acute neck and back pain, still too many radiologic examinations were performed. The purpose of this study was to analyze and optimize diagnostics and treatment of patients with acute back pain. METHODS: The medical records of 484 patients presented to the emergency clinic with acute neck or back pain were analyzed for clinical history, physical examination, radiographic findings and therapy. RESULTS: Radiographs of the lumbar, cervical, or thoracic spine were performed in 338 cases (70%). Radiographs were normal in 142 patients (42%) and degenerative changes were identified in 123 patients (36%). Only 2 patients (0.4%) had radiographic findings that had direct therapeutic relevance: 1 patient with metastatic disease and 1 patient with posttraumatic C1-C2 instability. For most patients without sensorimotor deficits and absent specific indications for radiography ("red flags"), therapy was not affected by the results of radiography. CONCLUSIONS: Plain radiography of the spine was unnecessary in most patients initially evaluated with non-specific acute back pain and does not improve the clinical outcome. The implementation of national and international guidelines is a slow process, but helps to reduce costs and to protect patients from unnecessary ionizing radiation exposure.

Quality of life after surgery for neuromuscular scoliosis.

Surgery in patients with neuromuscular scoliosis is associated with a higher rate of complications. It is still controversially discussed whether the patients truly benefit from deformity correction. The purpose of this study is to investigate if the quality of life has been improved and if the patients and their caregivers are satisfied with the results of surgery. This is a retrospective clinical outcome study of 46 patients with neuromuscular scoliosis which were treated with primary stable posterior pedicle screw instrumentation and correction. To achieve fusion only autologous bone was used. Follow up was minimum 2 years and maximum 5 years with an average of 36 months. The patients and/or their caregivers received a questionnaire based on the PEDI (pediatric disability inventory) and the GMFS (gross motor function score). The patients (and their caregivers) were also asked if the quality of life has improved after surgery. Only 32 of 46 patients answered the questionnaire. The answers showed a high approval-rate regarding the patients satisfaction with the surgery and the improvement of quality of life. The questionnaire could be answered from 1 (I do not agree) to 4 (I completely agree). The average agreement to the following statements was: i) the quality of life has improved: 3.35; ii) I am satisfied with surgery: 3.95; iii) the operation has fulfilled my expectations: 3.76. The average age at surgery was 12.7 years. The mean pre-operative cobb-angle of the main curve was 83.1° with a correction post-operatively to a mean of 36.9° and 42.6° at final follow-up. That is an average correction of 56.9%. Although spinal fusion in neuromuscular scoliosis is associated with a higher rate of complications our results show that the patients and their caregivers are satisfied with the operation and the quality of life has improved after surgery.

Spontaneus bilateral pedicle fracture 30 years after Harrington Instrumentation for idiopathic scoliosis: a case report.

INTRODUCTION: Spontaneous fractures of the spine are a common entity. They usually occur in older people with osteoporosis. This case is presented on account of its rarity. To the best of the authors' knowledge only one case of an osteoporotic pedicle fracture after Harrington Instrumentation has been described before. CASE PRESENTATION: We report the case of a 46-year-old Caucasian woman who underwent surgery due to idiopathic scoliosis with a Harrington Instrumentation (T4 to L3) 30 years ago. During the operation she was infected with hepatitis C while receiving erythrocyte concentrates and has suffered from liver cirrhosis since then. She presented with a sudden pain in her lower back and paraesthesia in both her legs but no other neurological symptoms. A computed tomography scan showed a bilateral pedicle fracture of L3 and an additional compression fracture of L4. In the first session we performed a dorsal stabilization with massive intraoperative bleeding and a postoperative failure of liver synthesis. In a second session an additional ventral augmentation was done. After the second operation she developed a hepatorenal syndrome. Both operations left the patient in a very critical state which led to a prolonged stay in the intensive care and rehabilitation unit. At her 12-month follow-up visit, she was free of complaints. CONCLUSION: The un-physiological load of the spine after Harrington Instrumentation can lead to osteoporosis due to inactivity even in younger patients. Although these implants are not used anymore one should keep this possibility in mind when dealing with patients who have received Harrington rods in surgical procedures.

Functional characterization of novel loss-of-function mutations in the vasopressin type 2 receptor gene causing nephrogenic diabetes insipidus.

BACKGROUND: X-linked nephrogenic diabetes insipidus (NDI) is a rare polyuric disorder caused by inactivating mutations in the arginine vasopressin receptor Type 2 (AVPR2) gene. METHODS: NDI patients from six unrelated families were subjected to mutational analysis of the AVPR2 gene. In-depth in vitro characterization of novel AVPR2 mutants by a combination of functional and immunological techniques provided further insight into molecular mechanisms causing receptor dysfunction. RESULTS: Mutational analysis revealed four novel (A89P, G107R, Q174R, W208X) and three recurrent (V277A, R337X, ΔR247-G250) mutations within the AVPR2 gene. One family carried the missense mutation R337X and a 12-bp deletion (ΔR247-G250), corresponding to a fragment in the third intracellular loop (ICL3), which was not genetically linked to R337X. The functionally tested missense mutations A89P, G107R and Q174R led to reduced receptor cell surface expression in transfected COS-7 cells, most probably due to misfolding and intracellular retention, and consequently to reduction or loss of agonist-mediated cyclic adenosine monophosphate formation. Deletion of R247-G250 had no effect on receptor function in vitro. Comparison with other mammalian AVPR2 orthologs showed that this part of the ICL3 is structurally not conserved and, therefore, less relevant for receptor function. In contrast, all missense mutations (A89P, G107R, Q174R, V277A) affect receptor positions that were fully preserved during mammalian evolution. CONCLUSION: Our results provide valuable information about residues critical for AVPR2 folding, trafficking and function and proof that these mutations are responsible for causing NDI in the affected subjects.

Efficacy of post-operative analgesia after posterior lumbar instrumented fusion for degenerative disc disease: a prospective randomized comparison of epidural catheter and intravenous administration of analgesics.

This prospective study aimed to compare the efficacy of epidural (EDA) versus intravenous (PCA) application of analgesics after lumbar fusion. Fifty-two patients scheduled for elective posterior instrumented lumbar fusion were randomized into two groups. EDA patients received an epidural catheter intraoperatively, and administration of ropivacain and sulfentanil was started after a normal postoperative wake-up test in the recovery room area. PCA patients received intravenous opioids in the post-operative period. Differences between EDA and PCA groups in terms of patient satisfaction with respect to pain relief were not significant. Nevertheless, EDA patients reported less pain on the third day after surgery. There were significantly more side effects in the EDA group, including complete reversible loss of sensory function and motor weakness. There were no major side effects, such as infection or persisting neurological deficits, in either group. The routine use of epidural anesthesia for lumbar spine surgery has too many risks and offers very little advantage over PCA.

Validity and reliability of an adapted german version of scoliosis research society-22 questionnaire.

STUDY DESIGN: Study to determine the internal consistency and validity of adapted German version of Scoliosis Research Society-22 (SRS-22) questionnaire. OBJECTIVE: To evaluate the validity and reliability of adapted German version of SRS-22 questionnaire. SUMMARY OF BACKGROUND DATA: The SRS-22 questionnaire was developed to assess the health-related quality of life for English-speaking patients with idiopathic scoliosis. For scientific purpose and standardized comparison of outcome studies for the treatment of idiopathic scoliosis its adaptation into German is necessary to respect cultural and lingual differences. METHODS: Translation/retranslation of the English version of the SRS-22 was conducted, and all steps for cross-cultural adaptation process were performed. Thus, SRS-22 questionnaire and previously validated Roland-Morris score were mailed to 222 patients who had been treated surgically or conservatively for idiopathic scoliosis. Seventy-eight patients (35%) responded to the first set of questionnaires and 54 of the first time responder returned their second survey. The median age of all patients who joined the study was 19 years. Measures of reliability namely, selectivity, internal consistency, and reproducibility were determined by Cronbach's alpha statistics and intraclass correlation coefficient, respectively. Concurrent validity was measured by comparing with an already validated questionnaire (Roland-Morris score). Measurement was made using the Spearman correlation coefficient. RESULTS: The study demonstrated satisfactory internal consistency with high Cronbach's alpha values for 4 of the corresponding domains (pain, 0.75; self-image, 0.84; mental health, 0.88; and satisfaction, 0.61). However, the Cronbach's alpha value for function/activity domain (0.67) was considerably lower than the original English questionnaire. For the same domains intraclass correlation coefficient demonstrating satisfactory test/retest reproducibility. CONCLUSION: The adapted German version of the SRS-22 questionnaire can be used to assess the outcome of treatment for German-speaking patients with idiopathic scoliosis.

Comparison of surgical and conservative treatment for degenerative lumbar scoliosis.

INTRODUCTION: Demographic changes create an expansion of the elderly population segment of society. Demands of mobility and quality of life have increased in this age group over the last decades. A rising number of elderly patients suffering from degenerative "de novo" lumbar scoliosis (DLS) may be eligible for surgical options to treat their spinal deformities. Therefore, we compared the clinical and radiographic results of conservative and surgical treatment. MATERIALS AND METHODS: During 1990-2003, 55 patients with DLS were treated and followed up for a minimum of 24 months. Group 1 patients (n=26) underwent surgery (decompression and spondylodesis), group 2 patients (n=29) declined surgery and received conservative treatment (analgesics, physiotherapy). Clinical data, theatre records and X-rays were analysed. All patients were contacted and 73.1% of group 1 and 75.8% of group 2 patients were clinically re-evaluated and received standing radiographs on average 4.8 and 3.8 years after the initial procedure or consultation, respectively. RESULTS: We found a significantly higher rate of spinal stenosis and degenerative spondylolisthesis in group 1 patients (P<0.01). The procedure corrected the lumbar deformity in the frontal and sagittal planes. Three patients required revision for implant failure. Walking distance improved significantly during the postoperative course. Analgesic requirement decreased in comparison to group 2 patients. No significant difference was evident between the groups in terms of lumbar back pain after 3.8 and 4.8 years, respectively. CONCLUSION: Operative treatment of DLS with decompression in combination with a longer fusion improved walking ability and quality of life. Reduced need of analgesics can be anticipated. Benefits of surgery and risks of complications have to be considered carefully to avoid disappointment in expectations.

Surgical correction of scoliosis in children with congenital heart failure (Fontan circulation): case report and literature review.

Patients with Fontan circulation represent a significant cardiorespiratory risk during spinal surgery. We report about two patients with severe scoliosis and Fontan circulation and their successful operative treatment. The case report will be compared with the national and international literature.

Management of chronic low back pain: rationales, principles, and targets of imaging-guided spinal injections.

If low back pain does not improve with conservative management, the cause of the pain must be determined before further therapy is initiated. Information obtained from the patient's medical history, physical examination, and imaging may suffice to rule out many common causes of chronic pain (eg, fracture, malignancy, visceral or metabolic abnormality, deformity, inflammation, and infection). However, in most cases, the initial clinical and imaging findings have a low predictive value for the identification of specific pain-producing spinal structures. Diagnostic spinal injections performed in conjunction with imaging may be necessary to test the hypothesis that a particular structure is the source of pain. To ensure a valid test result, diagnostic injection procedures should be monitored with fluoroscopy, computed tomography, or magnetic resonance imaging. The use of controlled and comparative injections helps maximize the reliability of the test results. After a symptomatic structure has been identified, therapeutic spinal injections may be administered as an adjunct to conservative management, especially in patients with inoperable conditions. Therapeutic injections also may help hasten the recovery of patients with persistent or recurrent pain after spinal surgery.

Adjustment of pelvispinal parameters preserves the constant gravity line position.

There is a high variance in sagittal morphology and complaints between different subjects suffering from spinal disorders. Sagittal spinal alignment and clinical presentation are not closely related. Different parameters have been used to describe the pelvispinal morphology based on standing lateral radiographs. We conducted a study using radiography of the lumbar spine combined with force platform data to examine the correlation between pelvispinal parameters and the gravity line position. Fifty consecutive patients with a mean age of 55 years (18-84 years) were compared to normal controls. Among patients we found a statistically significant correlation between the following spinal parameters: lumbar lordosis and sacral slope (r=0.77; P<0.001), sacral slope and pelvic incidence (r=0.72; P<0.001) and pelvic tilt and overhang (r=-0.93; P<0.001). In patients and controls, the gravity line position was found to be located at 60 and 61%, respectively, of the foot length measured from the great toe, ranging from 53 to 69%, when corrected for the individual foot length. The results indicate that subjects with and without spinal disorders have their gravity line position localised within a very small range despite the high variability for lumbar lordosis and pelvic tilt.

Interobserver and intraobserver agreement of Lenke and King classifications for idiopathic scoliosis and the influence of level of professional training.

STUDY DESIGN: This is a blinded study of radiographs by observers with different levels of professional training. OBJECTIVES: To determine whether the level of professional training on nonmeasured and premeasured radiographs would affect reliability of Lenke's and King's classifications for adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Both classification systems have been studied for their reliability, mainly by observers with a high level of experience in orthopedics and scoliosis surgery using premeasured radiographs. METHODS: Examination of radiographs of 60 operative cases of adolescent idiopathic scoliosis was performed. On 5 occasions, 3 observers with a completely different degree of professional training measured and classified preoperative radiographs according to Lenke's or King's criteria. The results were determined by calculating the interobserver and intraobserver agreement and were quantified using two-rater and multirater kappa statistics. RESULTS: The Lenke and King classifications demonstrated poor to fair interobserver and good intraobserver agreement on nonmeasured radiographs. Both classifications demonstrated good to excellent interobserver agreement on premeasured radiographs. CONCLUSIONS: The results confirm that both classifications have a good reliability. On nonmeasured radiographs, the degree of professional training and the measurement process seem to influence the outcome. On premeasured radiographs, the interobserver agreement does not seem to be influenced by the level of professional training.

Prospective randomized comparison of radiation exposure from full spine radiographs obtained in three different techniques.

PROBLEM: The purpose of the investigation was a comparison of two different digital X-ray techniques with conventional standing full spine films. Evaluation of dose area product, image quality and inter-observer error of Cobb-angle measurement in patients with scoliosis and kyphoscoliosis were studied. METHODS: A consecutive series of 150 patients were prospectively randomized into three groups. Patients in group 1 (n=53) received a conventional standing postero-anterior full spine radiograph. All films were evaluated on the light box. Patients in group 2 (n=48) received a X-ray using the digital storage phosphor plate system (CR). For group 3 (n=49) digital pulsed fluoroscopy was used. In groups 2 and 3 images were exported to a picture archiving and communicating system (PACS) workstation and viewed on a monitor (Siemens SMM 21140P, Germany). Dose area product measurements were performed in all three groups (Diamentor-M, PTW, Freiburg). Three experienced investigators independently reviewed all pictures. Pedicles and endplates were counted. Cobb-angles of the main curves were measured. RESULTS: The mean dose area product was 97.0 cGy cm(2) (37.0-380.0 cGy cm(2)) for conventional films, 31.5 cGy cm(2) (6.0-66.0 cGy cm(2)) for CR imaging and 5.0 cGy cm(2) (1.0-29.0 cGy cm(2)) for digital fluoroscopy. The differences of Cobb-angle measurements were not significantly different for the three methods. Differences in the count of pedicles and endplates between the investigators were significantly lower for the conventional film as an indicator for the best detail presentation. CONCLUSION: A significant reduction in dose area product is possible with modern digital X-ray methods. The inter-observer error of Cobb-angle measurement is not significantly altered. The detail information is decreased in comparison to conventional films.