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

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.

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

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

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

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.

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

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.

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

Aims

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

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

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.

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.

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

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

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

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

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.

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.

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