Aims. The escalating demand for medical resources to address spinal diseases as society ages is an issue that requires careful evaluation. However, few studies have examined trends in spinal surgery, especially unscheduled hospitalizations or surgeries performed after hours, through large databases. Our study aimed to determine national trends in the number of spine surgeries in Japan. We also aimed to identify trends in after-hours surgeries and unscheduled hospitalizations and their impact on complications and costs. Methods. We retrospectively investigated data extracted from the Diagnosis Procedure Combination database, a representative inpatient database in Japan. The data from April 2010 to March 2020 were used for this study. We included all patients who had undergone any combination of laminectomy, laminoplasty, discectomy, and/or spinal arthrodesis. Results. This investigation included 739,474 spinal surgeries and 739,215 hospitalizations in Japan. There was an average annual increase of 4.6% in the number of spinal surgeries. Scheduled hospitalizations increased by 3.7% per year while unscheduled hospitalizations increased by 11.8% per year. In-hours surgeries increased by 4.5% per year while after-hours surgeries increased by 9.9% per year. Complication rates and costs increased for both after-hours surgery and unscheduled hospitalizations, in comparison to their respective counterparts of in-hours surgery and scheduled hospitalizations. Conclusion. This study provides important insights for those interested in improving spine care in an ageing society. The swift surge in after-hours spinal surgeries and unscheduled hospitalizations highlights that the medical needs of an increasing number of patients due to an ageing society are outpacing the capacity of existing medical resources. Cite this article: Bone Jt Open 2024;5(8):662–670

We reviewed 212 consecutive patients with adolescent idiopathic scoliosis who underwent posterior spinal arthrodesis using all pedicle screw instrumentation in terms of clinical, radiological and Scoliosis Research Society (SRS)-22 outcomes. In Group 1 (51 patients), the correction was performed over two rods using bilateral segmental pedicle screws. In Group 2 (161 patients), the correction was performed over one rod using unilateral segmental pedicle screws with the second ^{rod providing stability of the construct through two-level screw fixation at proximal and distal ends. The mean age at surgery was 14.8 years in both groups. Comparison between groups showed no significant differences with regard to age and Risser grade at surgery, pre- and post-operative scoliosis angle, coronal Cobb correction, length of hospital stay and SRS scores. Correction of upper thoracic curves was significantly better in Group 1 (p = 0.02). Increased surgical time and intra-operative blood loss was recorded in Group 1 (p < 0.001 and p = 0.04, respectively). The implant cost was reduced by mean 35% in Group 2 due to the lesser number of pedicle screws.}

Unilateral and bilateral pedicle screw techniques have both achieved excellent deformity correction in adolescent patients with idiopathic scoliosis, which was maintained at two-year follow-up. This has been associated with high patient satisfaction and low complication rates.

Cervical spinal arthrodesis is the standard of care for the treatment of spinal diseases induced neck pain. However, adjacent segment disease (ASD) is the primary postoperative complication, which draws great concerns. At present, controversy still exists for the etiology of ASD. Knowledge of cervical spinal loading pattern after cervical spinal arthrodesis is proposed to be the key to answer these questions. Musculoskeletal (MSK) multi-body dynamics (MBD) models have an opportunity to obtain spinal loading that is very difficult to directly measure in vivo. In present study, a previously validated cervical spine MSK MBD model was developed for simulating cervical spine after single-level anterior arthrodesis at C5-C6 disc level. In this cervical spine model, postoperative sagittal alignment and spine rhythms of each disc level, different from normal healthy subject, were both taken into account. Moreover, the biomechanical properties of facet joints of adjacent levels after anterior arthrodesis were modified according to the experimental results. Dynamic full range of motion (ROM) flexion/extension simulation was performed, where the motion data after arthrodesis was derived from published in-vivo kinematic observations. Meanwhile, the full ROM flexion/extension of normal subject was also simulated by the generic cervical spine model for comparative purpose. The intervertebral compressive and shear forces and loading-sharing distribution (the proportions of intervertebral compressive and shear force and facet joint force) at adjacent levels (C3-C4, C4-C5 and C6-C7 disc levels) were then predicted. By comparison, arthrodesis led to a significant increase of adjacent intervertebral compressive force during the head extension movement. Postoperative intervertebral compressive forces at adjacent levels increased by approximate 20% at the later stage of the head extension movement. However, there was no obvious alteration in adjacent intervertebral compressive force, during the head flexion movement. For the intervertebral shear forces in the anterior-posterior direction, no significant differences were found between the arthrodesis subject and normal subject, during the head flexion/extension movement. Meanwhile, cervical spinal loading-sharing distribution after anterior arthrodesis was altered compared with the normal subject's distribution, during the head extension movement. In the postoperative loading-sharing distribution, the percentage of intervertebral disc forces was further increased as the motion angle increased, compared with normal subject. In conclusion, cervical spinal loading after anterior arthrodesis was significantly increased at adjacent levels, during the head extension movement. Cervical spine musculoskeletal MBD model provides an attempt to comprehend postoperative ASD after anterior arthrodesis from a biomechanical perspective

Instrumented spinal arthrodesis is a common procedure to correct scoliosis. The long-term consequences of these retained implants is unclear. Concern of possible toxic effects of raised metal ion levels have been reported in arthroplasty literature. We investigated serum metal ion levels in patients having instrumented spinal arthrodesis for scoliosis correction. The study included patients who underwent posterior spinal arthrodesis using Isola stainless steel instrumentation for scoliosis between 1998 and 2002. Patients having post-operative complications, instrumentation removed, revision surgery or additional in situ metal implants were excluded. Participants completed a questionnaire to evaluate exogenous chromium exposure. Serum levels of chromium, molybdenum, iron and ferritin were measured in venous blood samples. Participants with elevated serum chromium levels underwent further erythrocyte chromium analysis. Comparisons were made with two control groups;. “non-instrumented” individuals with scoliosis and. “normal” unaffected volunteers. All control group participants underwent serum and erythrocyte analysis (as above). Thirty “instrumented” patients (Group 1, 26 females and 4 males), 10 “non instrumented” patients with scoliosis (Group 2) and 10 unaffected volunteers (Group 3) were included in the study. Mean age at surgery was 13.8 years (range 6.6 to 13.2), mean time from surgery 5.7 years (range 3.4 to 8.1). Elevated serum chromium levels were demonstrated in 11/30 (37%) Group 1 participants. In the control groups, elevated serum chromium levels were demonstrated in 0/10 (0%) in Group 2 and 2/10 (20 %) in Group 3. There was a statistically significant (p=0.001) elevation in serum chromium levels between scoliosis participants with retained spinal implants, and those without. There was no significant correlation found between Groups 1, 2 and 3 for serum molybdenum, iron and ferritin levels. Erythrocyte chromium measurements from all participants (n=31, 100%) were considered within the normal range. At a multivariant level, the results of a stepwise censored regression (n=50) indicated the significant predictors of serum chromium to be spinal implants (p=0.001), gender (male versus female, p=0.04) and iron grading (low, normal or high, p=0.05). Time since surgery was found not to have a significant correlation with chromium levels (p=0.147). Raised serum chromium levels were detected in 37% of patients after instrumented spinal arthrodesis for scoliosis correction. This new finding has relatively unknown health implications but potential genotoxic, dysmorphic and carcinogenic sequelae; this is especially concerning with most scoliosis patients being adolescent females with their reproductive years ahead

Summary of background data. The development of a spinal deformity, usually affecting the coronal and occasionally the sagittal balance of the spine is a recognised complication of paralysis following a spinal cord injury (SCI) occurring in childhood. Purpose of the study. The aim of the present study was to report our experience on the surgical treatment of patients who developed a paralytic spinal deformity secondary to SCIs occurring in childhood. Material-Methods. Our study cohort comprised 18 consecutive patients with a paralytic spinal deformity as a consequence of a SCI. The cause of paralysis in this group of patients included a traumatic incident in 10 patients, spinal cord tumour in 6 patients, vascular injury to the neural cord during cardiac surgery in one patient, and meningitis in one patient. Twelve patients presented with high- or mid-thoracic paraparesis, which was complete in all but two patients. Six patients developed tetraparesis, which was incomplete in 3 of these patients. Results. Fourteen patients underwent surgical correction of their spinal deformities; 11 patients had a scoliosis, 2 had a lordoscoliosis, and one had a kyphosis. The mean age at spinal arthrodesis was 13.4 years. Eleven patients underwent a posterior spinal fusion alone and 3 patients underwent a combined anterior and posterior spinal arthrodesis. Posterior spinal instrumentation with bilateral Luque rods and segmental fixation with sublaminar wires was used in all but one patient who was stabilised with the use of third generation spinal instrumentation. The spinal fusion extended to the sacrum in 10 of the 14 patients (71.4%) using the Galveston technique of intra-iliac pelvic fixation. None of the patients developed postoperative wound infections, either early or late. There were no major medical complications following surgery in this group of patients that would result in prolonged intensive care unit or hospital stay. Four of the 14 patients (28.6%) who had initially undergone a posterior spinal arthrodesis alone developed an asymptomatic pseudarthrosis with failure of the instrumentation. The non-union was treated successfully in 2 of these 4 patients with a combined anterior and posterior spinal fusion. The repair of the pseudarthrosis was performed through a repeat posterior spinal fusion in the remaining 2 patients and one of these patients necessitated a second revision procedure to address recurrence of the non-union. Conclusions. The high rate of pseudarthrosis (28.6%) recorded in the present series suggests that a combined anterior and posterior spinal arthrodesis could be considered as the initial treatment of choice for patients who are at a good general medical condition to tolerate anterior surgery and who have severe deformities. If pseudarthrosis develops following an isolated posterior spinal fusion, this can be treated more effectively by a combined anterior and posterior revision procedure with the use of instrumentation, which can increase the chances for a successful outcome

Introduction: Spinal arthrodesis with stainless steel implants is a common procedure to correct scoliosis however, the long-term consequences of retained implants is unclear. Raised serum metal ion levels have been widely published in arthroplasty literature with concern over possible toxic adverse effects associated with chronic exposure. We investigated serum metal ion levels in patients who had undergone instrumented spinal arthrodesis for scoliosis correction. Methods: The study included patients who underwent posterior spinal arthrodesis using ISOLA instrumentation for scoliosis between 1998 and 2002. The minimal period of follow up was 3 years. Clinical information was available from a comprehensive Scoliosis Database, Department of Orthopaedic Surgery, Women’s and Children’ Hospital, Adelaide (WCH). Patients having post-operative complications, spinal instrumentation removed, revision surgery or additional in situ metal implants were excluded. Participants completed a questionnaire to evaluate exogenous chromium exposure. Blood samples were collected and processed by the WCH Core Laboratory. Serum levels of chromium, molybdenum, iron and ferritin were measured by Sydney South West Pathology Service. Participants with serum chromium levels outside the normal reference range underwent further analysis to evaluate chromium levels in erythrocyte haemolysate preparations (to assess the valency of abnormal chromium levels detected). Comparisons were made with two control groups; the first being individuals with scoliosis who had not undergone operative intervention and the other, “normal” unaffected volunteers. All control group participants underwent serum and erythrocyte analysis (as above). Ethics approval was obtained from the WCH Research Ethics Committee. Results: Thirty patients (26 females and 4 males) who underwent instrumented scoliosis surgery, 10 non instrumented scoliosis patients and 10 unaffected volunteers were included in the study. Mean age of the operative group at surgery was 13.8 years (11.1–16.9) with a mean length of time from surgery of 5.8 years (3.5–8.2). In the study group, raised serum chromium levels were demonstrated in 11/30 (36.6%) of patients. Five of the 11 patients with raised chromium levels also had low levels of serum iron and/or ferritin. Erythrocyte levels of chromium were undetectable in all of the 11 (100%) patients. There did not appear to be an exogenous source of chromium exposure in any of these patients. In the non-operative control group with scoliosis, none had elevated serum chromium, iron or ferritin levels. 2/10 (20%) had high molybdenum levels. In the unaffected control group, 1/10 (10%) had raised serum chromium and molybdenum levels. Three control patients had low levels of serum iron and/or ferritin. All control participants, but one, had undetectable erythrocyte chromium levels. There was a significant difference in serum chromium levels between the study and control groups (p=0.01) with the group of patients who underwent instrumented scoliosis surgery having a greater proportion with high chromium and lower proportion with normal chromium. Discussion: Raised serum chromium levels were detected in patients after instrumented spinal arthrodesis for scoliosis correction. This new finding in young patients has relatively unknown health implications but potential genotoxic and carcinogenic sequelae; this is especially concerning with most scoliosis patients being female and with their reproductive years ahead. These findings should prompt further research in this area, particularly to similarly investigate other spinal implant systems and assess the long term implications of raised chromium levels

Scheuermann's kyphosis is a structural deformity of the thoracic or thoracolumbar spine, which can result in severe pain, neurological compromise and cosmetic dissatisfaction. Modern surgical techniques have improved correction through a posterior-only or antero-posterior approach but can result in significant morbidity. We present our results of the surgical management of severe Scheuermann's kyphosis by a single surgeon with respect to deformity correction, global balance parameters, functional outcomes and complications at latest follow-up. We included 49 patients, of which 46 had thoracic and 3 had thoracolumbar kyphosis. Surgical indications included persistent back pain, progressive deformity, neurological compromise and poor self-image. Fourty-seven patients underwent posterior-only and 2 antero-posterior spinal arthrodesis utilising Chevron-type osteotomies and hybrid instrumentation. Mean age at surgery was 16.0 years with mean postoperative follow-up of 4.5 years. Mean kyphosis corrected from 92.1o to 46.9o (p<0.001). Concomitant scoliosis was eliminated in all of the 28 affected patients. Coronal and sagittal balance was corrected in all patients. Mean blood loss was 24% total blood volume. Mean operation time was 4.3 hours with mean inpatient stay of 9 days. SRS-22 questionnaire improved from a mean preoperative score of 3.4 to 4.6 at 2 years, with high treatment satisfaction rates. Complications included one toxic septicaemia episode but otherwise no wound infections, no junctional deformity, no loss of correction and no requirement for re-operation. Posterior spinal arthrodesis with the use of hybrid instrumentation can safely achieve excellent correction of severe Scheuermann's kyphosis helping to relieve back pain, improve functional outcomes and enhance self-image

Aim:. To determine radiographic variables that predict the need for distal extension of the fusion beyond Cobb-to-Cobb levels in treating thoracolumbar/lumbar (TL/L) scoliosis (Lenke 5) in adolescent patients. Method:. We reviewed the medical notes and radiographs of the senior author's consecutive series of 53 adolescent patients with TL/L scoliosis treated by posterior instrumented spinal arthrodesis using an all-pedicle screw construct. Our patients were categorised into 2 groups: patients with instrumented fusion between Cobb-to-Cobb levels of the TL/L curve (Group 1), and patients that required distal extension beyond the caudal Cobb level (Group 2). Pearson correlation and binary logistic regression analyses (significance p<0.05) were performed to identify variables that predict the need for distal extension. Results:. Groups 1 and 2 comprised 36 and 17 patients, respectively. The following preoperative parameters significantly correlated with distal extension of the fusion: TL/L scoliosis angle (TL/L), TL/L supine maximum lateral bending angle, TL/L apical vertebral translation (AVT), TL/L flexibility index (FI), lowest instrumented vertebra angle (LIVA), and compensatory thoracic scoliosis angle (TH). Binary logistic regression analysis optimised a predictive equation incorporating TL/L, AVT, FI, LIVA, and TH parameters that provides an 81% accuracy in predicting the need for Cobb-to-Cobb fusion or distal extension. There was no difference in demographic data or SRS-22 scores between the 2 groups. Discussion:. Regression analysis of preoperative radiographic variables can accurately predict the need for distal extension of the fusion beyond the preoperative Cobb-to-Cobb levels during posterior spinal arthrodesis in patients with adolescent idiopathic thoracolumbar/lumbar scoliosis. Conflict Of Interest Statement: No conflict of interest

Introduction. This research determines the feasibility of radiostereometric analysis (RSA) as a diagnostic tool for assessing fusion following spinal arthrodesis. Further, to estimate clinical thresholds for precision and accuracy of the proposed method in the cervical and lumbar spine. Methods. Two-level lumbo-sacral and three-level cervical posterior arthrodesis procedures were performed on an artificial spine model and a cadaveric spine (Figure 1). Using a spring-loaded inserter, RSA marker beads were placed within each of the L4-S1 and C3-C6 vertebrae, then analyzed for optimal bead distribution and detection. RSA imaging consisted of 12 double exams (24 exams) of the cervical and lumbar regions for both the Sawbones and cadaveric spine to assess precision of measurement under zero-displacement conditions, defined as the 95% confidence interval of error. Accuracy assessment was performed on the Sawbones model in which the middle vertebrae (L5 and C4-C5) were moved relative to the superior (L4 and C3) and inferior (S1 and C6) vertebrae by known, incremental displacements (Figure 2). RSA images were obtained at each displacement (Figure 3). Accuracy was defined as the mean difference between known and measured displacements. Results. Median RSA bead detection was 100% in cervical vertebrae and >75% in lumbar vertebrae in the artificial and cadaveric models. Translational RSA precision for both spine models was better than 0.25mm and 0.82mm for the lumbar and cervical regions, respectively. Rotational precision was better than 0.4° and 1.9° for the lumbar and cervical regions, respectively. RSA accuracy for the artificial spine overall demonstrated less than 0.11 mm translational bias (margin < ±0.02 mm) and less than 0.22° rotational bias (margin < ±0.15°). Discussion and Conclusion. This study demonstrates that RSA achieves sufficient precision and accuracy to detect intervertebral micromotion for the purpose of assessing arthrodesis. Well dispersed bead placement is critical to achieving sufficient accuracy and avoiding occlusion by metal hardware. The results of this work will aid in the development of a clinical study to assess arthrodesis in patients. For any figures or tables, please contact the authors directly

The purpose of this research was to determine the feasibility of radiostereometric analysis (RSA) as a diagnostic tool for assessing non-union following spinal arthrodesis procedures. Further, to estimate clinical thresholds for precision and accuracy of the proposed method in the cervical and lumbar spine. A three-level lumbo-sacral and a four-level cervical posterior arthrodesis procedures were performed on an artificial spine model (Sawbones, WA). Using a spring loaded inserter (RSA Biomedical, Sweden), eight to ten RSA markers were placed within each of the L4 and L5 segments in the spinous process (L4 only), lamina, transverse processes, posterior and anterior (down the pedicle) wall of the vertebral body. Eight to ten markers were placed within the proximal sacrum (S1) at the medial and lateral crests, tuberosity, and within the sacral canal wall. Four to eight RSA markers were placed into the C3-C6 lateral masses. Titanium screws and rods were applied to the spinal segments. Identical procedures were then performed on a cadaveric spine using similar bead placement and hardware. RSA imaging consisted of 12 double exams (24 exams) of the cervical and lumbar regions for both the Sawbones and cadaveric spine to assess precision of measurement under zero-displacement conditions. The most distal vertebrae were considered the datum against which the movement of all other vertebrae was compared. The artificial spine was then dismantled for accuracy assessment in which the middle vertebrae (L5 and C4-C5) were moved relative to the superior (L4 and C3) and inferior (S1 and C6) vertebrae by known, incremental displacements on an imaging phantom device. Displacements occurred along the superior-inferior, anterior-posterior, and flexion-extension (rotational) axes of motion. RSA images were obtained at each displacement. Image analysis was performed using model-based software (RSACore v3.41, Leiden, Netherlands) to visualize implanted RSA beads in 3-D space. Precision was defined as the 95% confidence interval of error in measuring zero-displacement. Accuracy was defined as the mean difference (with 95% confidence interval) between the known and measured displacement. The rate of RSA bead detection was high with 5–8 implanted beads being visible in both the lumbar and cervical regions of the artificial and cadaveric spines. Translational RSA precision for both spines was better than 0.25 mm and 0.82 mm for the lumbar and cervical regions, respectively. Rotational precision was better than 0.40° and 1.9° for the lumbar and cervical regions, respectively. RSA accuracy for the artificial spine overall demonstrated less than 0.11 mm translational bias (margin < ±0.02 mm) and less than 0.22° rotational bias (margin < ±0.15°). This study demonstrates that RSA achieves sufficient precision and accuracy to detect intervertebral micromotion for the purpose of assessing arthrodesis. Well dispersed RSA bead placement is critical to achieving sufficient accuracy as well as avoiding occlusion by metal hardware. Cervical bead implantation is particularly sensitive to bead clustering due to small vertebrae size and proximity to critical structures. The results of this work will aid in the development of a clinical study to assess arthrodesis in patients

Aim:. To present 11 patients with quadriplegia who developed severe lordoscoliosis or hyperlordosis. This is a rare deformity in children with CP, treatment is challenging and there are less than 20 patients ever reported. Method:. All patients underwent posterior spinal arthrodesis at mean age 14.6 years with mean follow-up 3.5 years. We measured all radiographic parameters including coronal and sagittal balance and sacral slope before and after surgery. Results:. Mean preoperative lumbar lordosis was 107°. This corrected to mean 63° at follow-up. Mean preoperative thoracic kyphosis was 13°. This improved to mean 47° at follow-up. Mean preoperative scoliosis was 80°. This corrected to mean 22o at follow up. Mean preoperative pelvic obliquity was 22°. This corrected to mean 4° at follow-up. Mean preoperative sacral slope was 80o. This corrected to mean 51o at follow-up. Mean preoperative coronal imbalance was 5.2 cm. This corrected to mean 0.6 cm at follow-up. Mean preoperative sagittal imbalance was 8 cm. This corrected to mean 1.6 cm at follow-up. Mean surgical time was 260 minutes. Mean intra-operative blood loss was 0.82 EBV. Mean stay in ICU was 3.6 and in hospital 15.2 days. Complications included 3 patients with severe blood loss (1.3–2 EBV), one patient with chest and one chest and urinary infection, and a patient with superior mesenteric artery syndrome. Increased preoperative lumbar lordosis and sacral slope correlated with surgical and postoperative morbidity. In contrast, there was no correlation between preoperative scoliosis or pelvic obliquity and surgical morbidity. Reduced lumbar lordosis and increased thoracic kyphosis correlated with better global sagittal balance at follow-up. Greater surgical time and blood loss correlated with increased postoperative morbidity. All 11 patients and their parents reported excellent feedback on the outcome of surgery with major improvement in physical appearance, sitting balance and relief of severe preoperative back pain. Discussion:. Lordoscoliosis and hyperlordosis are associated with significant morbidity in patients with quadriplegia. The sagittal imbalance is the major component of the deformity and this can be corrected satisfactorily through a posterior spinal arthrodesis which produced excellent functional results and increased patients'/caretakers' satisfaction. Conflict Of Interest Statement: No conflict of interest

OP-1 is a bone morphogenetic protein which induces bone formation. For this reason, this protein is used to treat congenital pseudoarthrosis and post-traumatic non-union as well as to improve healing of bone grafting in orthopaedic surgery. In the present study we report the results of treatment in 10 patients in whom OP-1 was used to improve bone healing. Four patients were operated because of post-traumatic non-union, one because of congenital pseudo-arthrosis and four because of spinal arthrodesis, whereas one had a tibial lenghthening with poor bone formation. At follow-up, ranging from 6 to 16 months after the operation, we observed satisfactory bone formation in all cases. Although the number of our cases is limited, our results confirm the effectiveness of OP-1 in the treatment of post-traumatic non-union and spinal arthrodesis

Purpose. Bone morphogenic protein (BMP-2) is used in spinal arthrodesis to induce bone growth. Studies have demonstrated that it achieves similar fusion rates compared to iliac crest bone graft when used in instrumented fusions. Our study aims at evaluating the requirement for instrumentation in one and two-level spinal arthrodeses when BMP-2 is used in conjunction with local bone to achieve fusion. Method. 50 patients were recruited and randomized to instrumented versus non-instrumented spinal arthrodesis. BMP-2 with local autologous bone was used in all patients. Patients are evaluated at 3-months, 6-months, 12-months, and 24-months postoperatively with questionnaires to assess clinical outcome (ODI, VAS and SF-36), and PA and lateral x-rays of the spine to assess radiographic fusion (Lenke score). At 24 months, a thin-cut (1mm) CT scan was performed. Results. Two-year data is available on 40 patients. There were no statistically significant differences between the two groups based on the clinical outcomes measured. The ODI 22.55.1 for the instrumented group vs. 13.733.57 for the non-instrumented group (p=0.2)). The VAS for the instrumented group was 2.110.61 vs. 1.530.61 for the non-instrumented group (p=0.49). The SF-36 (physical) was 62.316.71 for the instrumented group vs 54.665.43 for the study group (p=0.8). The operating time was 105.85.91 minutes for the instrumented group versus 88.63.61 minutes for the non-instrumented group (p=0.01). Blood loss was 339.139.38 cc for the instrumented group vs 273.133.8 cc for the non-instrumented group (p=0.1). Preliminary radiographic analysis showed similar fusion rates for the two groups. Two-year follow-up on all patients will be completed by February 2010. Final clinical and radiographic data analysis will be presented at the meeting. Conclusion. BMP-2 and local bone graft demonstrated functionally equivalent clinical outcomes when used with or without instrumentation in lumbar spinal fusions while offering potential reduction in operative time and blood loss

Introduction: Spinal deformities (scoliosis, kyphosis or kyphoscoliosis) in children under 10 years of age result from congenital, neuromuscular and idiopathic etiologies. The progression of the deformity is affected by its nature, location and age of onset. Spinal arthrodesis is the procedure of choice in patients with progressive deformities. The use of instrumentation facilitates curve correction and arthrodesis rates. Pediatric spinal surgery is technically demanding, and is still considered controversial. The advent of reduced size spinal instrumentation allowed surgeons to expand their use to pediatric patients. The use of spinal instrumentation in children with various spinal deformities has not been well documented. Objective: To assess the safety and efficacy of spinal arthrodesis in young patients with progressive spinal deformities. Patients and Methods: We retrospectively reviewed the medical charts and radiographs of 25 patients younger than 10 years of age who underwent corrective surgery for various spinal deformities. Radiographic outcome, fusion rates and complication were compared between instrumented and non instrumented patients. Results: At two years of follow up instrumented corrective procedures resulted in superior correction compared to non-instrumented patients and in solid arthrodesis in all. Complications were infrequent. Conclusions: The use of reduced size spinal instrumentation in young patients with progressive spinal deformities is safe and effective. Curve correction, length of bracing and fusion rates are all in favour of instrumentation, wile complication rates are acceptable. The use of spinal instrumentation in young patients requires expertise and patience

Introduction and Aims: Elevated chromium ion levels can be detected in serum following spinal arthrodesis with stainless steel. Comparing characteristics of spinal implants with chromium levels has not been done extensively before. The aim of our study was to compare an extensive range of implant characteristics with chromium levels. Methods: Cross-sectional study of 30 patients (26 females and 4 males) who underwent posterior instrumented spinal arthrodesis using Isola implants including cables for adolescent scoliosis between 1998 and 2002. Patients who had postoperative complications and implants removed were excluded. Serum levels of chromium were analysed between October 2006 and June 2007. Post-operative radiography was used to measure rod length and count hooks, screws, cross-connectors and cables. Surface areas of each component of the implant was estimated and totalled. Metal-on-metal interfaces were calculated. Ethics approval was obtained from the WCH Research Ethics Committee. Results: Both total surface area and total rod length were correlated with serum chromium levels (p = 0.04 and 0.05 respectively). This is the first study to identify a characteristic of spinal implants, other than the late signs of corrosion identified by radiographs, which has significance for serum chromium levels. None of our patients had signs of corrosion, pseudoarthrosis or rod breakage on radiological examination. Compared to raised serum chromium levels, the number of metal-onmetal interfaces approached significance (p = 0.09). Individual numbers of screws, hooks, cables or cross-connectors were not significantly associated with chromium levels. Conclusions: Total rod length may contribute to elevated chromium levels in patients with stainless steel Isola spinal implants and warrants further investigation

Purpose: The current gold standard for spinal arthrodesis, autologous bone graft harvested from the iliac crest, has several disadvantages including donor site morbidity, blood loss, delayed wound healing, and increased operative time. Our study explores a Demineralized Bone Matrix-Calcium Sulfate(DBM-CaSO4) composite graft with autologous bone marrow aspirate (BMA), and compares it to autologous iliac crest bone graft in lumbar and lumbosacral spinal fusions. Method: A total of 80 patients were recruited for the study and randomised, via a computer-generated ran-domisation schedule, to autologous iliac crest bone graft (control) or DBM-CaSO4 composite graft with BMA (study) groups. Patients were evaluated at three-months, six-months, 12-months and 24-months post-operatively with questionnaires to evaluate clinical outcome (Oswestry disability questionnaire (ODI), visual analogue pain scales (VAS), and validated SF-36) and with posteroanterior and lateral x-rays of the spine to evaluate radiological outcome. Results: At 24-months post-operatively, there were no statistical differences seen between the two groups based on the clinical outcomes measured. Average ODI values were 27.19 for the control group versus 22.68 for the study group (p > 0.05). The average back VAS pain for the control group was 3.50 versus 3.51 for the study group (p > 0.05). The SF-36 score was 89.22 for the control group versus 91.56 for the study group (p > 0.05). The average operative time was 115.7 minutes for the control group versus 104.2 minutes for the study group (p: 0.014). Average calculated blood loss was 571.9 cc for the control group versus 438.2 cc for the study group (p: 0.025). The Lenke score was 1.92 for the control group versus 2.66 for the study group (p: 0.004). Conclusion: At two year follow-up, radiographic fusion was slightly higher in the ICBG. However, clinical outcomes were equivalent in both groups. Moreover, the DBM-CaSO4 and BMA composite graft offered the advantages of decreased blood loss and shorter operative time. Therefore, the DBM-CaSO4 and BMA composite graft represents a viable alternative to autologous iliac crest bone graft in carefully selected patients undergoing spinal arthrodesis

Purpose of the study. We report septic shock as postoperative complication following an instrumented posterior spinal arthrodesis on a patient with multiple body piercings. The management of this potentially catastrophic complication and outcome of treatment is been discussed. Summary of Background Data. Body piercing has become increasingly more common due to change in culture or as a fashion statement. This has been associated with local or generalized ill effects including tissue injury, skin and systemic infections, and septic shock. There is no clear guideline pathway regarding removal and reinsertion of body piercings in patients who undergo major surgery. Complications following Orthopaedic or Spinal procedures associated with body piercing have not been reported. Methods. We reviewed the medical notes and radiographs of an adolescent patient with severe Scheuermann's kyphosis and multiple body piercings who underwent an uneventful posterior spinal arthrodesis with pedicle hook/screw/rod instrumentation and autologous iliac crest bone graft and developed septic shock. Results. Septic shock developed on postoperative day 2 after reinsertion of all piercings following patient's request. The patient became systemically very unwell and required intensive medical management, as well as a total course of antibiotics of 3 months. The piercings remained in situ. She did not develop a wound infection despite the presence of bacteraemia (coagulase-negative Staphylococci/Streptococci warneri) and spinal instrumentation. The patient had no new piercings subsequent to her deformity procedure. Two and a half years after spinal surgery she reported no medical problems, had a balanced spine with no loss of kyphosis correction and no evidence of nonunion or recurrence of deformity. Conclusion. The development of septic shock as a result of piercing reinsertion in the postoperative period has not been previously reported. This is an important consideration to prevent potentially life-threatening complications following major spinal surgery. Despite the wide array of complications associated to body art there are no clear guidelines for body piercing. There is growing public awareness and several countries are laying regulations which have not yet been internationally standardized. A clear practice guideline in the perioperative management of piercings is needed as the incidence of body piercing and associated complications is rising. There is need for surgeons to be aware of the hazards of body piercing and its implications. We propose that multiple piercings should not be reinserted after major surgery and appropriate counseling should be provided to the patients as part of the consent process

Summary of Background Data. Obstruction of the third part of the duodenum by the superior mesenteric artery (SMA) is associated with spinal manipulation in the surgical or conservative management of scoliosis. Purpose of the study. The aim of the present study was to investigate the prevalence of SMA syndrome in a cohort of 165 consecutive pediatric patients who underwent spine deformity surgery and had minimum 2-year follow-up. Material-Methods. The study group comprised 85 patients with idiopathic scoliosis, 20 patients with neuromuscular and 18 patients with miscellaneous or syndromic scoliosis, and 42 patients with congenital spinal deformities. Posterior spinal arthrodesis was performed in 94 patients, combined anterior/posterior in 60 patients, and anterior spinal fusion in 11 patients. Results. We identified 4 patients who developed SMA syndrome postoperatively. These were all markedly underweight, adolescent females; 2 patients had adolescent idiopathic scoliosis, one had neuromuscular, and one congenital scoliosis. Third generation instrumentation systems with derotational effect were used in 3 patients. The spinal arthrodesis in the patient with neuromuscular scoliosis was performed using bone graft followed by application of a spinal jacket. The symptoms developed at a mean of 3.7 days post-surgery and included nausea, vomiting, increased nasogastric aspirates, abdominal pain and distension. Conservative management with prolonged nasojejunal feedings achieved resolution of the symptoms in all but one patient, who required derotation of the duodenum and jejunum. There was no evidence of recurrence of the condition in any patient at the latest follow-up. Conclusions. The prevalence of SMA syndrome in our series was 2.4%. This draws attention to the significance of prevention of the condition by recognizing patients who are at a higher risk. An early diagnosis of the syndrome will allow for application of conservative methods and will increase the chances for a successful outcome

Purpose of the study. To investigate the efficacy of pedicle screw instrumentation in correcting spinal deformity in patients with quadriplegic cerebral palsy. Also to assess quality of life and functional improvement after deformity correction as perceived by the parents of our patients. Summary of Background Data. All pedicle screw constructs have been commonly used to correct adolescent idiopathic scoliosis. There is limited information on their effectiveness in treating patients with cerebral palsy and neuromuscular scoliosis. Methods. We reviewed the medical records and serial radiographs of 45 consecutive patients with quadriplegia who underwent spinal arthrodesis using pedicle screw/rod instrumentation and a standardised surgical technique (prospectively collected single surgeon's series). All patients were wheelchair bound with collapsing thoracolumbar scoliosis and pelvic obliquity. Twenty-eight patients had associated sagittal deformities. A telephone survey was performed by an independent investigator to assess parents' perception on surgical outcome. Results. Thirty-eight patients underwent posterior-only and 7 staged anteroposterior spinal arthrodesis. Mean age at surgery was 13.4 years (range 9-18.3) and mean postoperative follow-up 3.5 years (range 2.8-5). Pedicle screw instrumentation extended from T2/T3 to L5 with bilateral pelvic fixation using iliac bolts. Scoliosis was corrected from mean 82.5° to 21.4° (74.1%). Pelvic obliquity was corrected from mean 24° to 4° (83.3%). In posterior-only procedures, average blood loss was 0.8 blood volumes, ICU stay 3.5 days, and hospital stay 17.6 days. In anteroposterior procedures, average blood loss was 0.9 blood volumes, ICU stay 8.9 days, and hospital stay 27.4 days. Major complications included one deep infection and one re-operation to remove prominent implants but no deaths, no neurological deficit and no detected pseudarthrosis. Parents' survey demonstrated 100% satisfaction rate. Conclusion. Pedicle screw instrumentation can achieve excellent correction of spinopelvic deformity in quadriplegic cerebral palsy with low complication and re-operation rates and high parent satisfaction. Our study has demonstrated that spinal correction using segmental pedicle screw/rod constructs can be performed safely and with lesser major complications and reoperations compared to the traditionally used Unit rod or hybrid instrumentation. The greater degree of deformity correction and lesser rate of complications and reoperations due to non-union, prominent instrumentation or failed pelvic fixation using a pedicle screw compared to the Unit rod technique should be balanced against the increased implant cost

Autograft – Since before modern surgical techniques were described, ancient Greeks new of the possibilities for bone to grow after fracture. Studying open fractures, often post mortem, they new of the importance of both the “amount and integrity of bone architecture” that was necessary for two ends of a bone to heal. More recently, modern spinal surgical techniques, many pioneered by surgeons such as John Moe MD, use the same knowledge that for the intentional arthrodesis of two or more bony spinal levels there requires a certain amount and quality of bone – both capturing osteoinductive and osteoconductive properties. Autograft can be harvested in many ways for spinal arthrodesis and can be taken from iliac crest, tibia or fibula, and from local vertebral sources. Often requiring a separate skin and/or fascial incision, morbidities such as pain, neurovascular injury, infection, blood loss, haematoma, seroma, and fracture can plague the technique. Limited quantities, especially in children, can also be an issue with autograft. Cancellous or cortico-cancellous structural grafts can be milled and used for posterolateral fusion, interbody fusion, and can be mixed with other graft substitutes/expanders. Morbidity profile aside, autograft still remains the gold standard for spinal arthrodesis with regards “ideal properties” of bone grafts. Allograft – Currently, allograft is the most common substitute for autograft bone in spinal fusion. Allograft is primarily osteoconductive, with minimal osteoinductive potential. Avoidance of donor site morbidity, quantity issues, and surgical time saving are all features of allograft. Increased costs and potential for infection are negative issues. Preparation can vary and fresh unprocessed grafts are no longer used. Freeze drying (lyophilization) involves drying of the grafts before freezing at sub zero temperatures, and the technique reduces immunogenicity, though upon rehydration, structural strength is lost by around 50%. Low dose radiation (< 20kGy) can also be used to process the grafts, as can ethylene oxide, yet both techniques also reduce mechanical strength of the trabecular architecture. With adequate donor screening and tissue processing, the risk of developing HIV from an allograft is estimated to be less than 1 in a million. Incorporation of allograft is similar to that of autograft, though the process takes more time. Allograft cancellous particles provide a larger surface area and therefore incorporate faster. Studies suggest that mulched allograft femoral heads provides as good a fusion rate in posterior spinal surgeries for children with scoliosis as does the use of autograft. Combination of osteoinductive agents (BMP etc) with allograft is now possible and will likely enhance its further use. Structural fibular allografts in cervical interbody fusion and femoral ring allografts in lumbar interbody fusion have been well described and have very high rates of fusion

Introduction. The mechanisms of how spinal arthrodesis (SA) affects patient function after total hip replacement (THA) remain unclear. The objectives of this study were to a) Determine how outcome post-THA compares between patients with- and without-SA, b) Characterize sagittal pelvic changes that occur when moving between different functional positions, and test for differences between patients with- and without-SA, and c) Assess whether differences in sagittal pelvic dynamics are associated with outcome post-THA. Patients/Materials & Methods. Forty-two patients with THA-SA (60 hips) were case-control matched for age, gender, BMI with 42 THA-only patients (60 hips). All presented for review where outcome, PROMs [including Oxford-Hip-Score(OHS)] and 4 radiographs of the pelvis and spino-pelvic complex in 3 positions (supine, standing, deep-seated) were obtained. Cup orientation and various spino-pelvic parameters [including pelvic tilt (PT) and Pelvic-Femoral-Angle (PFA)] were measured. The difference in PT between standing and seated allowed for patient classification based on spino-pelvic mobility into normal (±10–30°), stiff (<±10°) or hypermobile (>±30°). Results. The THA-SA group had inferior PROMs (OHS: 33vs.43; P<0.001) and more complications (12vs.3; p=0.01), especially dislocation (5vs.0) than the THA-only group. No difference in change of PT between supine and standing positions was detected between groups. When standing, THA-SA patients had greater PT (24°vs.17°; p=0.01) and the hip was more extended (194°vs.185°; P<0.001). THA-SA patients were 4 times more likely to have spino-pelvic hypermobility with anterior tilting of their pelvis. Of all biomechanical parameters, only spino-pelvic hypermobility was associated with significant inferior PROMs (OHS:35; p=0.04) and was also present in dislocating hips that required revision despite optimum cup orientation. Discussion. In patients with SA who have undergone a THA, the presence of spino-pelvic hypermobility is associated with an inferior outcome and leads to hip instability secondary to anterior impingement when deep seated (anterior tilt functionally retroverting cup). For those patients, current implant positioning may not be sufficient to avoid dislocation. Conclusion. THA in the presence of a SA is associated with inferior outcomes and higher complication rates. We recommend that assessing spino-pelvic mobility should form an integral part of pre-operative assessment in patients with SA due for a THA

Purpose of the study. Two patients with very severe thoracolumbar Scheuermann's kyphosis who developed spontaneous bony fusion across the apex of the deformity are presented and their treatment, as well as surgical outcome is discussed. Summary of Background Data. Considerable debate exists regarding the pathogenesis, natural history and treatment of Scheuermann's kyphosis. Surgical correction is indicated in the presence of severe kyphosis which carries the risk of neurological complications, persistent back pain and significant cosmetic deformity. Methods. We reviewed the medical notes and radiographs of 2 adolescent patients with severe thoracolumbar Scheuermann's kyphosis who developed spontaneous posterior and anteroposterior fusion across the apex of the deformity. Results. Patient 1. A male patient aged 17 years and 11 months underwent kyphosis correction when the deformity measured 115o and only corrected to 100o on supine hyperextension radiograph against the bolster; he had a small associated scoliosis. The surgery involved a combined single-stage anterior and posterior spinal arthrodesis T4-L3 with the use of posterior pedicle hook/screw/rod instrumentation and autologous rib graft. The anterior longitudinal ligament was ossified from T10 to L1 with bridging osteophytes extending circumferentially from T11 to T12 at the apex of kyphosis and displacing the major vessels anteriorly. The intervertebral discs from T9 to T12 were very stenotic and immobile. The osteophytes were excised both on the convexity and concavity of the associated thoracolumbar scoliosis. The anterior longitudinal ligament was released and complete discectomies back to the posterior longitudinal ligament were performed from T7 to L1. During the posterior exposure, the spine was found to be spontaneously fused across the apex of the kyphosis from T9 to L1. There were no congenital vertebral anomalies. Extensive posterior apical closing wedge osteotomies were performed from T7 to T12. The fused facets and ossified ligamentum flavum were excised and the spine was mobilised at completion of the anterior and posterior osteotomies. The kyphosis was corrected using a cantilever maneuver from proximal to distal under spinal cord monitoring. Excellent correction to 58o was achieved and maintained at follow-up. Autologous rib graft was used to enhance a solid bony fusion. Patient 2. A female patient aged 18 years and one month underwent kyphosis correction when the deformity measured 115o and only corrected to 86o on supine hyperextension radiograph against the bolster; she had a small thoracolumbar scoliosis. The surgery involved a single-stage posterior spinal arthrodesis T2-L4 with the use of posterior pedicle hook/screw/rod instrumentation and autologous iliac crest bone. The spine was spontaneously fused across the apex of kyphosis from T9 to L1. There were no congenital vertebral anomalies. Extensive posterior apical closing wedge osteotomies were performed from T6 to T12. The fused facets and ossified ligamentum flavum were excised and the spine was mobilised at completion of the osteotomies. The kyphosis was corrected using a cantilever maneuver from proximal to distal under spinal cord monitoring. Excellent correction to 60o was achieved and maintained at follow-up. Autologous iliac crest graft was used to achieve a solid bony fusion. In both patients the preoperative MRI assessed the intraspinal structures but failed to diagnose the solid fusion across the posterior bony elements at the apex of kyphosis. A CT scan with 3D reconstruction would have illustrated the bony anatomy across the kyphosis giving valuable information to assist surgical planning. This is recommended in the presence of rigid thoracolumbar Scheuermann's kyphosis which does not correct in hyperextension, especially if the plain radiograph shows anterior bridging osteophytes. Conclusion. Spontaneous posterior or anteroposterior fusion can occur across the apex of severe thoracolumbar Scheuermann's kyphosis; this should be taken into account when surgical correction is anticipated. The bony ankylosis may represent the natural history of an extreme deformity as an attempt of the spine to auto-stabilise. A combination of factors including a rigid deformity, which limits significantly active movement of the spine, as well as anterior vertebral body wedging with severe adjacent disc stenosis which induces bridging osteophyte formation may result in the development of spontaneous fusion across the apex of the kyphosis either posteriorly or anteroposteriorly. In the presence of an isolated posterior fusion, segmental posterior closing wedge osteotomies with complete excision of the ossified ligamentum flavum and fused facets should mobilise the thoracolumbar spine and allow for kyphosis correction. An additional anterior spinal release including complete discectomies, resection of the anterior longitudinal ligament and osteophytes is required if the bony fusion extends anteroposteriorly. Patients with Scheuermann's kyphosis should be ideally treated at an earlier stage and with a lesser degree of deformity so that this ossification process is prevented

Background. Bone Morphogenetic Protein (BMP) has been used in clinical practice to stimulate fracture healing and spinal arthrodesis. Difficulty in localising and maintaining BMP at the target site has resulted in the use of large doses of BMP, and has been associated with significant adverse effects. We have previously shown clay hydrogels can bind growth factors for localised efficacy. We hypothesised that localisation of BMP within clay gels would reduce the dose required to mediate bone formation. Methods. 2×10-4mg and 1×10-5 mg BMP were mixed in Laponite and applied to collagen sponge. 3 sponges containing high dose, and 3 containing low dose BMP were implanted subcutaneously in a mouse. This process was repeated in 8 mice, for controls, alginate hydrogel was used in a further 8 mice, and 1 mouse received 6 blank collagen scaffolds. Micro Computed Tomography was used to assess bone formation fortnightly; at 8 weeks the mice were culled and underwent histological analysis. Results. Mean Bone Volume formed within collagen per μg BMP was significantly greater with Laponite and low dose BMP compared to Alginate and Laponite with high dose BMP (p<0.0001). No bone formation was observed with Alginate and low dose BMP. Conclusions. We have demonstrated that Laponite is able to reduce, by several orders, the effective dose of BMP required to mediate ectopic bone formation compared to current gold standard methods of BMP delivery. Clinical translation of this finding offers, potentially, great significance to orthopaedic surgery. Level of Evidence. In vivo study. Approval. Our study received ethical approval complied with Home Office licensing. Acknowledgments. Funded by grants from EU(FP7) Biodesign, Rosetrees Trust, BBSRC and EPSRC

Aim:. Our aim was to report the rate and risk factors for post-operative complications in Duchenne Muscular Dystrophy (DMD) patients undergoing spinal arthrodesis for scoliosis, with a comparison to neuromuscular scoliosis of other aetiology. Methods:. From a prospective single surgeon spinal deformity database, we identified all patients with neuromuscular disorders who underwent surgical correction for progressive scoliosis. We recorded demographic and peri-operative data, including complications and subsequent procedures. The rate and risk factors for complications was determined, with a sub-analysis of the DMD group to determine any peri-operative factors predictive of overall complication rates. Results:. There were 98 patients, 59 (60%) were male with mean age at surgery 14 yrs (7–19 yrs). Forty-eight patients had cerebral palsy (n=48, 49%) and 26 DMD (27%). The overall complication rate was 18.4% (n=18), with deep wound infection (DWI; n=9, 9.2%) and acute liver injury (ALI; n=4, 4.0%) most frequent. The complication rate was significantly higher in DMD patients (35%) compared to other neuromuscular disorders (13%; p=0.013). All ALIs occurred in DMD patients (p=0.004), with an increased DWI rate (19% vs 6%; p=0.053). On subanalysis, no peri-operative factors correlated with overall complication rate or DWI rate. Increased intraoperative blood loss was the only factor associated with ALI (p=0.036). Discussion:. Scoliosis correction has an acceptable complication rate in patients with neuromuscular diagnoses. DMD patients have an increased complication rate when compared to other neuromuscular disorders. ALI in our series was unique to DMD patients and we would recommend peri-operative vigilance for hepatotoxicity in these patients. Conflict Of Interest Statement: No conflict of interest

Lowest instrumented vertebra (LIV) selection is critical to preventing complications following posterior spinal arthrodesis (PSA) for thoracolumbar/lumbar adolescent idiopathic scoliosis (TL/L AIS), but evidence guiding LIV selection is limited. This study aimed to investigate the efficacy of PSA using novel unilateral convex segmental pedicle screw instrumentation (UCS) in correcting TL/L AIS, to identify radiographic parameters correlating with distal extension of PSA, and to develop a predictive equation for distal fusion extension using these parameters. We reviewed data (demographic, clinical, radiographic, and SRS-22 questionnaires) preoperatively to 2-years' follow-up for TL/L AIS patients treated by PSA using UCS between 2006 to 2011. 53 patients were included and divided into 2 groups: Group-1 (n=36) patients had PSA between Cobb-to-Cobb levels; Group-2 (n=17) patients required distal fusion extension. A mean curve correction of 80% was achieved. Mean postoperative LIV angle, TL/L apical vertebra translation (AVT), and trunk shift were lower than previous studies. Six preoperative radiographic parameters significantly differed between groups and correlated with distal fusion extension: thoracic curve size, thoracolumbar curve size, LIVA, AVT, lumbar flexibility index, and Cobb angle on lumbar convex bending. Regression analysis optimised an equation (incorporating the first five parameters) which is 81% accurate in predicting Cobb-to-Cobb fusion or distal extension. SRS-22 scores were similar between groups. We conclude that TL/L AIS is effectively treated by PSA using UCS, six radiographic parameters correlate with distal fusion extension, and a predictive equation incorporating these parameters reliably informs LIV selection and the need for fusion extension beyond the caudal Cobb level

Subjects. A prospective study of 127 patients who underwent posterior spinal arthrodesis and segmental spinal instrumentation with iliac crest bone graft for correction of adolescent idiopathic scoliosis. Patients were divided according to their Cobb angle into two groups. Group 1 (n= 78) with a Cobb angle > 70° who underwent an additional concave rib osteotomy (CRO) and group 2 (n= 49) with a Cobb angle < 70° who did not (NCRO). All patients received a pulmonary rehabilitation programme post-operatively. Vital capacity (VC) and peak expiratory flow rate (PEF) were measured pre-operatively, at 3 months and 12 months post-operatively. Summary of background data. Concave rib osteotomy technique is used for giving more mobility and flexibility of the spine during correction especially in rigid and severe curves. Only a few studies in the literature have looked at the effect of concave rib osteotomy on pulmonary function. Results. ∗Curve correction: the mean Cobb angles at the pre-operative and final follow-up for group 1 (CRO) were 82.2° and 10.9° respectively (87% correction). In group 2 (NCRO), the mean Cobb angle was 62.77% pre-operatively and 6.9% at the final follow-up (89% correction achieved). ∗Pulmonary function: Pre-operative: there was no significant difference between the 2 groups. 3 Months post-operative: the mean VC was 40.4% in group 1 and 48.05% in group 2 (p=0.05). The mean PEF was 27.38 % in group 1and 34.1% in group 2 (p = 0.02). 12 Months post-operative: the mean VC in group 1 was 102.4% versus 103.5% in group 2 (p = 0.43). The mean PEF in group 1 was 76.2% versus 73.5% in group 2 (p = 0.32). Conclusions. Concave Rib Osteotomy technique has a definite effect on the pulmonary function in the early post-operative period. However, this difference resolves with time and both groups had a similar outcome a year post-operatively

Introduction. Posterior spinal arthrodesis with thoracoplasty and an open anterior approach, with respect to a posterior only fusion, have a deleterious effect on pulmonary function for up to 5 years after surgical treatment of adolescent idiopathic scoliosis. We aimed to compare two groups of adolescents surgically treated for their spinal deformity either by posterior segmental fusion alone (PSF) or by posterior spinal fusion and thoracoplasty (PSF+T). We focused on the long-term effects of thoracoplasty on pulmonary function in the surgical treatment of adolescent idiopathic scoliosis. Methods. We compared 40 consecutive adolescent patients surgically treated between 1998 and 2001 by PSF+T with a similar cohort of 40 adolescents treated in the same period by PSF. Inclusion criteria were pedicle screw instrumentation alone and a minimum 5 years of follow-up. A radiographic analysis and a chart review were done, evaluating the pulmonary function tests (PFTs), the SRS-30 score questionnaire, and the Lenke classification system. A radiographic rib-hump (RH) assessment was also undertaken. Results. The entire series was reviewed at an average clinical follow-up of 8·3 years. The two groups did not differ significantly in terms of sex, age (PSF+T 16·3 years vs PSF 15·2 years), Lenke curve type classification, and preoperative Cobb main thoracic (MT) curve magnitude (66° vs 63°); however, final MT percentage correction (53·03% vs 51·35%; p<0·03), RH absolute correction (–2·1 cm vs –1·05; p<0·01), and RH overall percentage correction (55·4% vs 35·4%; p<0·0001) were greater in the PSF+T group than in the PSF group. We recorded no statistical differences between the two groups in PFTs both preoperatively and at last follow-up. Nevertheless, comparing preoperative with final PFTs within each group, only in the PSF group was both forced vital capacity and forced expiratory volume in 1 s significantly improved at final evaluation. At last follow-up visit, the SRS-30 scores did not differ significantly between the two groups (total score 4·1 vs 4·3). Conclusions. Our findings suggest that thoracoplasty did not adversely affect long-term PFTs in patients with adolescent idiopathic scoliosis treated by posterior spinal fusion alone with pedicle screws instrumentation, as already shown in previous reports. A trend towards better coronal plane correction and rib-hump improvement was recorded, although this improvement was not clearly reported in a self-assessment disease-specific questionnaire

Summary of Background Data: The craniofacial malformations described by Goldenhar can be associated with congenital anomalies of the vertebrae. This non-random association of abnormalities represents unilateral errors in the morphogenesis of the spine, as well as the first and second branchial arches. Purpose of the study: The aim of the present study was to determine the prevalence of Goldenhar related conditions in patients with congenital deformities of the spine and to describe the types of vertebral abnormalities and the necessity for treatment. Material-Methods: We performed a retrospective study of 668 consecutive patients with congenital deformities of the spine. The medical records and spinal radiographs were reviewed and patients with a Goldenhar associated condition were identified. The vertebral anomalies causing the spine deformity were detected on antero-posterior and lateral spine radiographs. The type and site of the craniofacial abnormalities, as well as other musculoskeletal deformities and systemic anomalies were recorded. Results: Fourteen patients had Goldenhar associated conditions (7 males and 7 females). A thoracic scoliosis was the most common type of deformity occurring in ten patients (71.5%). Eight of these patients had an isolated hemivertebra and the remaining two had a unilateral unsegmented bar with contralateral hemivertebra at the same level. There was only one patient with a lumbar scoliosis and this was due to a hemivertebra. The side of the vertebral anomaly correlated with that of the hemifacial microsomia in five of the eleven patients who had a scoliosis or kyphoscoliosis. A thoracolumbar kyphosis occurred in four patients; two had posterior hemivertebrae, one had wedge vertebrae, and the remaining patient had an anterior unsegmented bar. A thoracolum-bar kyphoscoliosis occurred in only one patient and was due to a posterolateral quadrant vertebra. Klippel-Feil syndrome occurred in six patients (42.8%). Eight patients (57%) underwent surgical treatment at a mean age of 9.8 years (range: 2.9–19). Four patients had a combined anterior-posterior spine arthrodesis. The remaining four patients had a posterior spinal arthrodesis. Conclusions. The prevalence of Goldenhar associated conditions in patients with congenital deformities of the spine was 2%. Failures of vertebral segmentation were the most frequent abnormality in the cervical spine, whereas failures of vertebral formation most commonly occurred in the thoracic or thoracolumbar spine

Objective: To evaluate the outcomes and complications of one-stage and two-stage combined anterior-posterior spine fusion, and to document which procedure is more efficacious and provides better results. Study Design-Material: A retrospective study was performed including 45 pediatric patients with spastic quadriplegic cerebral palsy and neuromuscular scoliosis who underwent anterior-posterior spinal fusion. Summary of Background Data: Circumferential spinal arthrodesis has been proven to achieve better scoliotic curve correction, decreasing significantly the risk of pseudarthrosis and progression of the deformity. There have been a few studies comparing same-day versus staged anterior-posterior spinal surgery in mixed populations with neuromuscular scoliosis, but not in an isolated group of pediatric patients with spastic cerebral palsy. Methods: The medical records and radiographs of all patients were reviewed, and the results were statistically analyzed. The complications were divided into medical, subcategorized into major and minor, and technical. Results: There was no statistically significant difference (p> .05) between one-stage (group 1) and two-stage (group 2) patients, considering age at surgery, preoperative scoliosis angle, pelvic obliquity, kyphosis angle, lordosis angle, levels of anterior release, percentage of scoliosis correction, radiographic follow-up, hospitalization time and intensive care unit stay. Sequentially performed spinal procedures (group 1) were associated with increased intraoperative blood loss, prolonged operative time, and a considerably higher incidence of medical and technical complications, including two perioperative deaths. Conclusions: Two-stage anteroposterior spinal fusion provides safer and more consistent results with several advantages over the single-stage procedure in the management of patients with cerebral palsy and neuromuscular scoliosis. Since this study cannot separate risk based on disease severity, staging the procedures on different days is likely more important in individuals with very large curves and concomitant medical illness

Objective: To evaluate the outcomes and complications of one-stage and two-stage combined anterior-posterior spine fusion, and to document which procedure is more efficacious and provides better results. Study Design-Material: A retrospective study was performed including 45 pediatric patients with spastic quadriplegic cerebral palsy and neuromuscular scoliosis who underwent anterior-posterior spinal fusion. Summary of Background Data: Circumferential spinal arthrodesis has been proven to achieve better scoliotic curve correction, decreasing significantly the risk of pseudarthrosis and progression of the deformity. There have been a few studies comparing same-day versus staged anterior-posterior spinal surgery in mixed populations with neuromuscular scoliosis, but not in an isolated group of pediatric patients with spastic cerebral palsy. Methods: The medical records and radiographs of all patients were reviewed, and the results were statistically analyzed. The complications were divided into medical, subcategorized into major and minor, and technical. Results: There was no statistically significant difference (p> .05) between one-stage (group 1) and two-stage (group 2) patients, considering age at surgery, preoperative scoliosis angle, pelvic obliquity, kyphosis angle, lordosis angle, levels of anterior release, percentage of scoliosis correction, radiographic follow-up, hospitalization time and intensive care unit stay. Sequentially performed spinal procedures (group 1) were associated with increased intraoperative blood loss, prolonged operative time, and a considerably higher incidence of medical and technical complications, including two perioperative deaths. Conclusions: Two-stage anteroposterior spinal fusion provides safer and more consistent results with several advantages over the single-stage procedure in the management of patients with cerebral palsy and neuromuscular scoliosis. Since this study cannot separate risk based on disease severity, staging the procedures on different days is likely more important in individuals with very large curves and concomitant medical illness

Objective: To document an unusual pattern of clinical presentation simulating cerebral palsy and investigate the evolution of spinal deformity in relation to patients’ growth and responsiveness to levodopa therapy. Study Design-Material: A retrospective study was performed including 3 pediatric patients with dopa-responsive dystonia who developed in the course of their disease spinal curvatures. Summary of Background Data: Dopa-responsive dystonia has been recognized as a separate type of idiopathic dystonia with early onset, gradual generalized involvement, diurnal fluctuation of symptoms, spinal malalignment, and remarkable response to levodopa. Nevertheless, it can present with atypical features including prominent spastic elements and intrafamilial variability of expression. Methods: The medical records and radiographs of the 3 patients were reviewed. Results: All 3 siblings were normal at birth and had negative family history of neurological disease or spinal imbalance. Soon they developed progressive neurological impairment with exaggerated spasticity, underestimated dystonic patterns, and marked phenotypic variation, leading to the initial misdiagnosis of spastic-dystonic cerebral palsy of familial inheritance. With further growth, patient 1 and 3 developed spinal deformity, which responded dramatically to levodopa treatment and resolved spontaneously, while the neurological symptoms persistently ameliorated. Patient 2 developed a rigid C-shaped thoracolumbar scoliotic curve measuring at age 10 years 88o; even though she demonstrated considerable overall improvement with levodopa, the spinal curvature remained unresponsive and necessitated surgical correction through a combined anterior-posterior instrumented spinal fusion extending to the sacrum. However, her ambulatory function was preserved. Conclusions: Spinal decompensation is a common manifestation of dopa-responsive dystonia with excellent prognosis if adequate diagnosis and initiation of levodopa treatment are made early. On the contrary, if diagnosis and levodopa treatment are delayed, spinal deformity may progress following the rapid evolution pattern of neuromuscular curves, necessitating surgical intervention. When spinal arthrodesis is required, inclusion of the lumbosacral joint does not preclude latter ambulatory function

Objective: The aim of this study was to delineate parents’ and professional caretakers’ satisfaction after spinal fusion in children with spasticity, and to determine differences in their perceptions. Study Design-Methods: A questionnaire assessing patients’ functional improvement after spinal arthrodesis for correcting scoliosis was addressed to 190 parents. An expanded questionnaire was also addressed to 122 educators and therapists working exclusively in the care of children with cerebral palsy. Results: The vast majority of parents and caregivers reported a very positive impact of the surgery on patients’ overall function, quality of life, and ease of care. Caretakers did not recognize effects of the scoliotic deformity on patients’ head control, hand use, and feeding ability. Parents had more appreciation of the benefits in the children’s appearance, while educators and therapists acknowledged more improvement in gross and oral motor function. Most parents (95.8%) and caretakers (84.3%) would recommend spinal surgery, considering that the benefits from scoliosis correction clearly outweigh the increased risk of surgical complications in this group of severely involved patients. Conclusions: Correction of spinal deformity in children with cerebral palsy is associated with a very high parents’ and caretakers’ satisfaction rate, with both groups reporting excellent improvement in appearance, comfort, ease of care, and some functional gains. The answers received during the survey demonstrated clearly that the vast majority of parents and caretakers consider the surgical outcome of the spinal fusion very beneficial for the patients’ overall function and level of care. There were documented differences in the perceived positive impact of spine surgery in children with cerebral palsy between the two groups. Parents stated more consistent benefits from correcting scoliosis in the patients’ appearance, whereas therapists and educators delineated the improvement in the gross and oral motor function. However, both groups considered that the benefits from correcting scoliotic deformity undoubtedly offset the potential risks from surgery, and would have no hesitation in recommending this procedure for children with cerebral palsy who develop significant scoliosis interfering with their level of function and their overall quality of life

Introduction: The radiographic criteria for successful lumbar arthrodesis remains controversial. Plain radiographs including flexion-extension views are commonly used to assess fusion, but there is disagreement on the degree of apparent motion that is significant. Helical CT assessment of bridging bone between vertebrae is considered to be the most accurate method currently available. This study compared the use of plain radiographs including flexion-extension views with helical CT scans in the assessment of lumbar interbody fusion. Methods: Plain radiographs (including flexion-extension views) and helical CT scans were performed on 32 patients (47 levels) five years after ALIF using carbon fibre cages and autologous bone. A radiologist assessed fusion utilising the Hutter method to detect movement, whilst a spinal surgeon measured movement in degrees using the Simmons method. Helical CT scans (with sagittal and coronal reformatting) were assessed for the presence of bridging trabecular bone. Results: The radiographic fusion rate was 85% based on the presence of bridging bone, and also 85% with the Hutter method. The fusion rate was 74% when movement of at least two degrees was considered significant, but was 98% with the five degrees cut off adopted by the FDA. Fusion as determined by the presence of bridging trabeculae on helical CT Scans occurred in 67%. Concordance rates were as follows: between plain films and helical CT, 69.5%; between Hutter method and plain films, 76%; between Simmon’s method (two degrees) and helical CT, 67%; and between Simmon’s method with the FDA cut-off of five degrees and CT, 65%. Discussion: The assessment of fusion with radiographs appears to be unreliable. The use of plain films and flexion-extension radiographs clearly overestimated the actual fusion rates. Furthermore, there was low concordance between these methods and the more reliable helical CT. This disparity between fusion rates from radiographs and with helical CT supports the view that plain radiographs, including flexion-extension films are of limited value in the assessment of spinal arthrodesis

Purpose of the study. To investigate the efficacy of pedicle screw instrumentation in correcting thoracolumbar/lumbar idiopathic scoliosis in adolescent patients. Summary of Background Data. Thoracolumbar/lumbar scoliosis has been traditionally treated through an anterior approach and instrumented arthrodesis with the aim to include in the fusion the Cobb-to-Cobb levels and preserve distal mobile spinal segments. Posterior instrumentation has been extensively used for thoracic or thoracic and lumbar scoliosis. In the advent of all-pedicle screw constructs there is debate on whether thoracolumbar/lumbar scoliosis is best treated through an anterior or a posterior instrumented arthrodesis. Methods. We reviewed the medical notes and radiographs of 19 consecutive adolescent patients with Lenke 5C idiopathic scoliosis (17 female-2 male, prospectively collected single surgeon's series). We measured the scoliosis, thoracic kyphosis and lumbar lordosis angles, apical vertebral rotation (AVR) and translation (AVT), trunk shift (TS), as well as the lower instrumented vertebra angle (LIVA) both pre-and post-operatively and at minimum 2-year follow-up. SRS 22 data was available for all patients. Results. All patients underwent posterior spinal arthrodesis of the primary thoracolumbar/lumbar curve using all-pedicle screw constructs. Mean age at surgery was 15.1 years. We identified 3 separate groups: Group 1 (9 patients) had a fusion to include the preoperative Cobb-to-Cobb levels of the curve; in Group 2 (8 patients) the fusion extended 1-2 levels distal (all patients) +/− proximal (4 patients) to the end Cobb vertebrae; in Group 3 (2 patients) the fusion extended to one level proximal to the lower end Cobb vertebra. Eight patients had compensatory thoracic curves. Mean Cobb angle before surgery was 60.3° (range: 43-91°). This was corrected by 79% to mean 13° (p<0.001) with no patient losing >2° correction at follow-up. Mean preoperative Cobb levels of the thoracolumbar/lumbar curve were 6.3; mean levels of instrumented fusion were 7 (mean extent of fusion: preoperative Cobb angle + 0.7 levels). Mean preoperative thoracic kyphosis was 34.7° and lumbar lordosis 45.3°. Mean postoperative thoracic kyphosis was 36.6° and lumbar lordosis 43°. Mean theatre time was 3.8 hours, hospital stay 7.5 days and intraoperative blood loss 0.26 blood volumes. There were no neurological complications other than one temporary brachial plexus neuropraxia (recovered before patient discharge from hospital), no wound infections or detected non-union at follow-up. Mean preoperative SRS 22 score was 3.7; this was improved to 4.5 at 2-year follow-up (p=0.01). Pain and self-image demonstrated significant improvement (p=0.02, p=0.001 respectively) with mean satisfaction rate 4.8. Comparison between Groups 1 and 2 showed similar age at surgery but higher preoperative scoliosis in Group 2 (Group 1: 54°/Group 2: 65°, p=0.05). Preoperative AVR, TS and LIVA were similar between the 2 groups (p>0.05). Preoperative AVT was significantly higher in Group 2 (Group 1: 3.3 cm/Group 2: 5 cm, p=0.01). Conclusion. Pedicle screw instrumentation can achieve excellent correction of Lenke 5C idiopathic scoliosis which is maintained at follow-up. This is associated with high patient satisfaction and low complication rates. Greater preoperative AVT and scoliosis angle predicted the need for longer fusion both distally and proximally beyond the end vertebra of the preoperative Cobb angle

Introduction: Following a systematic review of the literature, de Kleuver. 1. concluded that there was insufficient data to assess the performance of total disc replacement. In the absence of controlled trials, the relative merits and efficacy of artificial disc replacement as a treatment option for degenerative disc disease was unproven. Observational studies reported a moderate success rate (50-81%), but a relatively high complication rate (3%–50%). In particular, 4% of the operated levels fused spontaneously or after revision surgery. Methods: Using the research methodology of the above study, all subsequent published studies of artificial lumbar disc replacement were identified and reviewed by meta-analysis. In the two years (2002–2003) since the above study, a further nine case series and three controlled studies have been reported. The three randomised controlled trials compared disc replacement with spinal fusion. Seven prospective studies (include the randomised controlled studies) had defined indications, exclusions and outcome measures. Results: A total of 623 disc replacements were performed in 510 patients. The outcomes were classified as “good” or “excellent”, ranged from 70–93% (mean=83%). Complications were observed in up to 35% (mean=3%) of patients. Eight patients subsequently underwent spinal arthrodesis at the level of the disc replacement. Two patients were reported to have heterotopicossification. The outcomes for the 2002–2003 publications were better (MWp=0.02) than for the de Kleuver study. Fewer patients had disc replacement at more than one level (FEp< 0.01). The number of patients undergoing secondary surgery (FEp< 0.01) and arthrodesis (FEp=0.04) was less and the incidence of prosthetic subsidence or migration was lower (FEp=0.28). This overall improvement in recent studies highlights the importance of patient selection and the use of a disc replacement of appropriate size. Following disc replacement, there was a significant improvement in outcome measures at six-week follow-up. This improvement was maintained at two years. While disc replacement reported significantly less pain and disability in the early period following surgery compared with the fusion, the difference was not significant by six months. Discussion: In the short to medium term, disc replacement is as effective as spinal fusion in the treatment of degenerative disc disease in critically selected patients. Although the number of complications has been reduced, some serious complications were reported. 2. A satisfactory salvage procedure for failed disc replacement is yet to be found. The long-term biological effects of disc replacement are unknown. Late failure of disc replacement is predictable in a substantial number of patients. Long-term studies of ten or more years are necessary to adequately define the place of disc replacement in the treatment of lumbar disc disorders. Because the numbers of disc replacement patients is likely to be small, protocols and outcome measures should be standardised and data centrally recorded

Introduction This in-vitro biomechanical study was undertaken to compare the multi-directional flexibility kinematics of single versus multi-level lumbar Charité reconstructions and determine the optimal biomechanical method for surgical revision – posterior instrumentation alone or circumferential spinal arthrodesis. Methods A total of seven human cadaveric lumbosacral spines (L1 to Sacrum) were utilized in this investigation and biomechanically evaluated under the following L4-L5 reconstruction conditions: 1) Intact Spine; 2) Diskectomy Alone, 3) Charité, 4) Charité + Pedicle Screws, 5) Two Level Charité (L4-S1), 6) Two Level Charité + Pedicle Screws (L4-S1), 7) Charité L4-L5 with Pedicle Screws and Femoral Ring Allograft (L5-S1) and 8) Pedicle Screws and Femoral Ring Allograft (L4-S1). Multi-directional flexibility testing utilized the Panjabi Hybrid Testing protocol, which includes pure moments for the intact condition with the overall spinal motion replicated under displacement control for subsequent reconstructions. Hence, changes in adjacent level kinematics can be obtained compared to pure moment testing strategies. Unconstrained intact moments of ±7Nm were used for axial rotation, flexion-extension and lateral bending testing, with quantification of the operative and adjacent level range of motion (ROM) and neutral zone (NZ). All data was normalized to the intact spine condition. Results In axial rotation, single and two level Charité reconstructions produced significantly more motion than pedicle screw constructs combined with the Charité or femoral ring allograft (p< 0.05). There were no differences between the Charité augmented with pedicle screws or pedicle screws with femoral ring allograft (p> 0.05). Similar trends were observed under flexion-extension and lateral bending conditions with the Charité reconstructions demonstrating no significant differences compared to the intact spine (p> 0.05). However, the Charité combined with pedicle screws or pedicle screws with femoral ring allograft significantly reduced motion at the operative level compared to the Charité reconstruction (p< 0.05). The most pronounced changes in adjacent level kinematics were observed at the inferior level. The addition of pedicle screw fixation, in all cases, increased segmental motion at the inferior adjacent level (L5-S1) compared to the intact and Charité reconstruction groups (p< 0.05). Discussion Single and two level total disc arthroplasty using the Charité device preserved segmental motion at the operative and adjacent levels compared to pedicle screw stabilization constructs. In terms of revision strategies, posterior pedicle screw reconstruction combined with an existing Charité is not statistically different from pedicle screws combined with femoral ring allograft. As we enter an era of total disc replacement and the impending necessity for surgical revision, the current study provides a biomechanical basis for posterior re-stabilization alone in lieu of combined anteroposterior revision

Introduction Total disc arthroplasty serves as the next frontier in the surgical management of intervertebral discogenic pathology. As we move from an era of interbody spinal arthrodesis to one in which segmental motion is preserved, this promising new technology offers increasing clinical and research challenges in the areas of spinal kinematics, histologic osseointegration at the prosthetic-bone interface and the effects of particulate wear debris. The primary focus of this paper is to provide a methodological basis to investigate the spinal kinematics, histologic osseointegration and particulate wear debris following total disc replacement arthroplasty using in-vitro and in-vivo models. MethodsPart I: Using an in-vitro cadaveric model, multidirectional flexibility testing evaluated the functional unit kinematics under the following L4-L5 reconstruction conditions: 1) Intact Spine; 2) Charitè Disc Prosthesis; 3) BAK Cages; 4) BAK Cages + ISOLA pedicle screw/rod fixation (anteroposterior). Part II: A total of twenty-seven mature baboons (n=27, Papio cynocephalus) underwent L5-L6 total disk replacement procedures to investigate the biomechanical, histochemical, and biologic ingrowth characteristics of two different lumbar disc prostheses – AcroFlex and Charite’ – for total disc replacement arthroplasty. Functional spinal unit fusion status was assessed using radiographic analysis, biomechanical testing, undecalcified histopathologic and histomorphometric analyses. Part III: Using a total of Fifty New Zealand White rabbits, the current study served to quantify the neural and systemic tissue histopathological response, following epidural application of four different types of spinal instrumentation particulate wear debris – 1) Sham (control) (n=10), 2) Stainless Steel 316LVM (n=10), 3) Titanium Alloy Ti-6AL-4V (n=10), 4) Cobalt Chrome Alloy (n=10) and 5) Ultrahigh molecular weight polyethylene (UHMWPE) (n=10). Results In-vitro multi-directional flexibility testing demonstrates the operative and adjacent level motion preserving properties of total disc arthroplasty versus interbody arthrodesis cages and pedicle screw spinal instrumentation. To this end, disc replacement preserves the normal centrode or locus of intervertebral rotation at the operative and adjacent intervertebral spinal levels compared to conventional stabilization implants. Based on non-human primate modeling in the current studies, porous titanium interface surfaces afforded the greatest percentage of trabecular in-growth at the prosthesis-end-plate interface. In-vivo segmental motion under multi-directional testing was preserved with the Charité device and slightly diminished with the AcroFlex implants. The porous ingrowth coverage at the bone-metal interface was more favorable for total disk replacement (range 40 to 50%) compared to that reported for cementless total joint components in the appendicular skeleton (range 10 to 30%). Direct epidural application of spinal instrumentation particulate wear debris elicits a chronic histiocytic reaction localized primarily within the epidural fibrous layers. Moreover, particles have the capacity to diffuse intrathecally, eliciting a macrophage / cytokine response within the epidural tissues, cerebrospinal fluid and spinal cord itself. Overall, based on the post-operative time periods evaluated, there was no evidence of an acute neural or systemic histopathologic response to the materials included in the current project. Conclusions The implementation of dynamic spinal stabilization systems for fusionless correction of spinal deformity, dynamic posterior stabilization and total disc replacement arthroplasty necessitates improved understanding with regard to spinal kinematics, patterns / mechanisms of histologic osseointegration and the neurohistopathologic response to particulate wear debris. Collectively, the current studies provide a methodological basis to comprehensively evaluate these three areas

Purpose of the study. To compare the effectiveness of unilateral and bilateral pedicle screw techniques in correcting adolescent idiopathic scoliosis. Summary of Background Data. Pedicle screw constructs have been extensively used in the treatment of adolescent patients with idiopathic scoliosis. It has been suggested that greater implant density may achieve better deformity correction. However, this can increase the neurological risk related to pedicle screw placement, prolong surgical time and blood loss and result in higher instrumentation cost. Methods. We reviewed the medical notes and radiographs of 139 consecutive adolescent patients with idiopathic scoliosis (128 female-11 male, prospectively collected single surgeon's series). We measured the scoliosis, thoracic kyphosis (T5-T12), and lumbar lordosis (L1-L5) before and after surgery, as well as at minimum 2-year follow-up. SRS 22 data was available for all patients. Results. All patients underwent posterior spinal arthrodesis using pedicle screw constructs. Mean age at surgery was 14.5 years. We had 2 separate groups: in Group 1 (43 patients) correction was performed over 2 rods using bilateral segmental pedicle screws; in Group 2 (96 patients) correction was performed over 1 rod using unilateral segmental pedicle screws with the 2. nd. rod providing stability of the construct through 2-level screw fixation both proximal and distal. Group 1. Mean Cobb angle before surgery for upper thoracic curves was 37°. This was corrected by 71% to mean 11° (p<0.001). Mean Cobb angle before surgery for main thoracic curves was 65°. This was corrected by 71% to mean 20° (p<0.001). Mean Cobb angle before surgery for thoracolumbar/lumbar curves was 60°. This was corrected by 74% to mean 16° (p<0.001). No patient lost >2° correction at follow-up. Mean preoperative thoracic kyphosis was 24° and lumbar lordosis 52°. Mean postoperative thoracic kyphosis was 21° and lumbar lordosis 50° (p>0.05). Mean theatre time was 5.5 hours, hospital stay 8.2 days and intraoperative blood loss 0.6 blood volumes. Complications: 1 transient IOM loss/no neurological deficit; 1 deep wound infection leading to non-union and requiring revision surgery; 1 rod trimming due to prominent upper end. Mean preoperative SRS 22 score was 3.9; this improved to 4.5 at follow-up (p<0.001). Pain and self-image demonstrated significant improvement (p=0.001, p<0.001 respectively) with mean satisfaction rate 4.9. Group 2. Mean Cobb angle before surgery for upper thoracic curves was 42°. This was corrected by 52% to mean 20° (p<0.001). Mean Cobb angle before surgery for main thoracic curves was 62°. This was corrected by 70% to mean 19° (p<0.001). Mean Cobb angle before surgery for thoracolumbar/lumbar curves was 57°. This was corrected by 72% to mean 16° (p<0.001). No patient lost >2° correction at follow-up. Preoperative scoliosis size for all types of curves correlated with increased surgical time (r=0.6, 0.4). Mean preoperative thoracic kyphosis was 28° and lumbar lordosis 46°. Mean postoperative thoracic kyphosis was 25° and lumbar lordosis 45° (p>0.05). Mean theatre time was 4.2 hours, hospital stay 8.4 days and intraoperative blood loss 0.4 blood volumes. Complications: 1 deep and 1 superficial wound infections treated with debridement; 1 transient brachial plexus neurapraxia; 1 SMA syndrome. Mean preoperative SRS 22 score was 3.7; this improved to 4.5 at follow-up (p<0.001). Pain, function, self-image and mental health demonstrated significant improvement (p<0.001 for all parameters) with mean satisfaction rate 4.8. Comparison between groups showed no significant difference in regard to age at surgery, preoperative and postoperative scoliosis angle for main thoracic and thoracolumbar/lumbar curves, as well as SRS scores and length of hospital stay. Better correction of upper thoracic curves was achieved in Group 1 (p<0.05), but upper thoracic curves in Group 2 were statistically more severe before surgery (p<0.05). Increased surgical time and blood loss was recorded in Group 1 (p<0.05, p=0.05 respectively). The implant cost was reduced by mean 35% in Group 2 due to lesser number of pedicle screws. Conclusion. Unilateral and bilateral pedicle screw instrumentation has achieved excellent deformity correction in adolescent patients with idiopathic scoliosis, which was maintained at follow-up. This has been associated with high patient satisfaction and low complication rates. The unilateral technique using segmental pedicle screw correction has reduced surgical time, intraoperative blood loss and implant cost without compromising surgical outcome for the most common thoracic and thoracolumbar/lumbar curves. The bilateral technique achieved better correction of upper thoracic scoliosis

Aims

A systematic literature review focusing on how long before surgery concurrent viral or bacterial infections (respiratory and urinary infections) should be treated in hip fracture patients, and if there is evidence for delaying this surgery.

Objectives

Pulsed electromagnetic field (PEMF) stimulation was evaluated after anterior cervical discectomy and fusion (ACDF) procedures in a randomized, controlled clinical study performed for United States Food and Drug Administration (FDA) approval. PEMF significantly increased fusion rates at six months, but 12-month fusion outcomes for subjects at elevated risk for pseudoarthrosis were not thoroughly reported. The objective of the current study was to evaluate the effect of PEMF treatment on subjects at increased risk for pseudoarthrosis after ACDF procedures.

Objectives

Long bone defects often require surgical intervention for functional restoration. The ‘gold standard’ treatment is autologous bone graft (ABG), usually from the patient’s iliac crest. However, autograft is plagued by complications including limited supply, donor site morbidity, and the need for an additional surgery. Thus, alternative therapies are being actively investigated. Autologous bone marrow (BM) is considered as a candidate due to the presence of both endogenous reparative cells and growth factors. We aimed to compare the therapeutic potentials of autologous bone marrow aspirate (BMA) and ABG, which has not previously been done.

Aims

Clinical and radiological data were reviewed for all patients with mucopolysaccharidoses (MPS) with thoracolumbar kyphosis managed non-operatively or operatively in our institution.

We report five children who presented at the mean age of 1.5 years (1.1 to 1.9) with a progressive thoracolumbar kyphosis associated with segmental instability and subluxation of the spine at the level above an anteriorly-wedged hypoplastic vertebra at L1 or L2. The spinal deformity appeared to be developmental and not congenital in origin. The anterior wedging of the vertebra may have been secondary to localised segmental instability and subsequent kyphotic deformity.

We suggest the term ‘infantile developmental thoracolumbar kyphosis with segmental subluxation of the spine’ to differentiate this type of deformity from congenital displacement of the spine in which the congenital vertebral anomaly does not resolve. Infantile developmental kyphosis with segmental subluxation of the spine, if progressive, may carry the risk of neurological compromise. In all of our patients the kyphotic deformity progressed over a period of three months and all were treated by localised posterior spinal fusion. At a mean follow-up of 6.6 years (5.0 to 9.0), gradual correction of the kyphosis was seen on serial radiographs as well as reconstitution of the hypoplastic wedged vertebra to normality. Exploration of the arthrodesis was necessary at nine months in one patient who developed a pseudarthrosis.

C5 nerve root palsy is a rare and potentially debilitating complication of cervical spine surgery. Currently, however, there are no guidelines to help surgeons to prevent or treat this complication.

We carried out a systematic review of the literature to identify the causes of this complication and options for its prevention and treatment. Searches of PubMed, Embase and Medline yielded 60 articles for inclusion, most of which addressed C5 palsy as a complication of surgery. Although many possible causes were given, most authors supported posterior migration of the spinal cord with tethering of the nerve root as being the most likely.

Early detection and prevention of a C5 nerve root palsy using neurophysiological monitoring and variations in surgical technique show promise by allowing surgeons to minimise or prevent the incidence of C5 palsy. Conservative treatment is the current treatment of choice; most patients make a full recovery within two years.

Cite this article: Bone Joint J 2014;96-B:950–5.

We report the incidence of and risk factors for complications after scoliosis surgery in patients with Duchenne muscular dystrophy (DMD) and compare them with those of other neuromuscular conditions.

We identified 110 (64 males, 46 females) consecutive patients with a neuromuscular disorder who underwent correction of the scoliosis at a mean age of 14 years (7 to 19) and had a minimum two-year follow-up. We recorded demographic and peri-operative data, including complications and re-operations.

There were 60 patients with cerebral palsy (54.5%) and 26 with DMD (23.6%). The overall complication rate was 22% (24 patients), the most common of which were deep wound infection (9, 8.1%), gastrointestinal complications (5, 4.5%) and hepatotoxicity (4, 3.6%). The complication rate was higher in patients with DMD (10/26, 38.5%) than in those with other neuromuscular conditions (14/84, 16.7% (p = 0.019). All hepatotoxicity occurred in patients with DMD (p = 0.003), who also had an increased rate of deep wound infection (19% vs 5%) (p = 0.033). In the DMD group, no peri-operative factors were significantly associated with the rate of overall complications or deep wound infection. Increased intra-operative blood loss was associated with hepatotoxicity (p = 0.036).

In our series, correction of a neuromuscular scoliosis had an acceptable rate of complications: patients with DMD had an increased overall rate compared with those with other neuromuscular conditions. These included deep wound infection and hepatotoxicity. Hepatotoxicity was unique to DMD patients, and we recommend peri-operative vigilance after correction of a scoliosis in this group.

Cite this article: Bone Joint J 2014; 96-B:943–9.

Objectives

Recent studies have shown that modulating inflammation-related lipid signalling after a bone fracture can accelerate healing in animal models. Specifically, decreasing 5-lipoxygenase (5-LO) activity during fracture healing increases cyclooxygenase-2 (COX-2) expression in the fracture callus, accelerates chondrogenesis and decreases healing time. In this study, we test the hypothesis that 5-LO inhibition will increase direct osteogenesis.

Impaction allograft is an established method of securing initial stability of an implant in arthroplasty. Subsequent bone integration can be prolonged, and the volume of allograft may not be maintained. Intermittent administration of parathyroid hormone has an anabolic effect on bone and may therefore improve integration of an implant.

Using a canine implant model we tested the hypothesis that administration of parathyroid hormone may improve osseointegration of implants surrounded by bone graft. In 20 dogs a cylindrical porous-coated titanium alloy implant was inserted into normal cancellous bone in the proximal humerus and surrounded by a circumferential gap of 2.5 mm. Morsellised allograft was impacted around the implant. Half of the animals were given daily injections of human parathyroid hormone (1–34) 5 μg/kg for four weeks and half received control injections. The two groups were compared by mechanical testing and histomorphometry. We observed a significant increase in new bone formation within the bone graft in the parathyroid hormone group. There were no significant differences in the volume of allograft, bone-implant contact or in the mechanical parameters.

These findings suggest that parathyroid hormone improves new bone formation in impacted morsellised allograft around an implant and retains the graft volume without significant resorption. Fixation of the implant was neither improved nor compromised at the final follow-up of four weeks.

We have updated our previous randomised controlled trial comparing release of chromium (Cr) and cobalt (Co) ions and included levels of titanium (Ti) ions. We have compared the findings from 28 mm metal-on-metal total hip replacement, performed using titanium CLS/Spotorno femoral components and titanium AlloFit acetabular components with Metasul bearings, with Durom hip resurfacing using a Metasul articulation or bearing and a titanium plasma-sprayed coating for fixation of the acetabular component.

Although significantly higher blood ion levels of Cr and Co were observed at three months in the resurfaced group than in total hip replacement, no significant difference was found at two years post-operatively for Cr, 1.58 μg/L and 1.62 μg/L respectively (p = 0.819) and for Co, 0.67 μg/L and 0.94 μg/L respectively (p = 0.207). A steady state was reached at one year in the resurfaced group and after three months in the total hip replacement group. Interestingly, Ti, which is not part of the bearing surfaces with its release resulting from metal corrosion, had significantly elevated ion levels after implantation in both groups. The hip resurfacing group had significantly higher Ti levels than the total hip replacement group for all periods of follow-up. At two years the mean blood levels of Ti ions were 1.87 μg/L in hip resurfacing and and 1.30 μg/L in total hip replacement (p = 0.001).

The study confirms even with different bearing diameters and clearances, hip replacement and 28 mm metal-on-metal total hip replacement produced similar Cr and Co metal ion levels in this randomised controlled trial study design, but apart from wear on bearing surfaces, passive corrosion of exposed metallic surfaces is a factor which influences ion concentrations. Ti plasma spray coating the acetabular components for hip resurfacing produces significantly higher release of Ti than Ti grit-blasted surfaces in total hip replacement.