Introduction. Pedicle subtraction osteotomy is a powerful technique for correcting sagittal imbalance in ankylosing spondylitis. There has been significant perioperative morbidity associated with this technique in the peer review literature. We present the Royal National Orthopaedic Hospital experience with a single surgeon retrospective study that was conducted to evaluate the outcomes in patients who underwent lumbar pedicle subtraction osteotomy for the correction of thoracolumbar kyphotic deformity in ankylosing spondylitis. Method. Twenty seven patients underwent a lumbar pedicle subtraction osteotomy and adjacent level posterior instrumentation between 1995 and 2010. There were 18 males and 9 females in the study. Events during the peri-operative course and post-operative complications were recorded. The radiological outcome and patient satisfaction were analysed with mean follow-up of one and a half years. Results. The mean operative time was three and half hours and the mean blood loss was 2290mls. Final follow-up radiograph showed an increase in lumbar lordosis angle from 17 degrees to 45 degrees. The sagittal imbalance improved by 85mm with the operation. Complications included loosening in two patients, one transient neurologic deficit and one infective non-union occurred overall. There were no mortalities from the surgery. Two patients developed junctional kyphosis and required a repeat operation. There was an improvement in the Oswestry Disability Score from a mean of 29 to 16 after the surgey. All (100%) of the patients were satisfied with the results of the procedure and would recommend the surgey to others. Conclusion. The study shows that pedicle subtraction extension osteotomy is effective for the correction of kyphotic deformity in ankylosing spondylitis

Clinically significant proximal junctional kyphosis (PJK) occurs in 20% of children treated with posterior distraction-based growth friendly surgery. In an effort to identify modifiable risk factors, it has been theorized biomechanically that low radius of curvature (ROC) implants (i.e., more curved rods) may increase post-operative thoracic kyphosis, and thus may pose a higher risk of developing PJK. We sought to test the hypothesis that EOS patients treated with low ROC (more curved rods) distraction-based treatment will have a greater risk of developing PJK as compared to those treated with high ROC (straighter) implants. This is a retrospective review of prospectively collected data obtained from a multi-centre EOS database on children treated with rib-based distraction with minimum 2-year follow-up. Variables of interest included: implant ROC at index (220 mm or 500 mm), patient age, pre-operative scoliosis, pre-operative kyphosis, and scoliosis etiology. In the literature, PJK has been defined as clinically significant if revision surgery with superior extension of the upper instrumented vertebrae was performed. In 148 scoliosis patients, there was a higher risk of clinically significant PJK with low ROC (more curved) rods (OR: 2.6 (95%CI 1.09-5.99), χ2 (1, n=148) = 4.8, p = 0.03). Patients had a mean pre-operative age of 5.3 years (4.6y 220 mm vs 6.2y 500 mm, p = 0.002). A logistic regression model was created with age as a confounding variable, but it was determined to be not significant (p = 0.6). Scoliosis etiologies included 52 neuromuscular, 52 congenital, 27 idiopathic, 17 syndromic with no significant differences in PJK risk between etiologies (p = 0.07). Overall, patients had pre-op scoliosis of 69° (67° 220mm vs 72° 500mm, p = 0.2), and kyphosis of 48° (45° 220mm vs 51° 500mm, p = 0.1). The change in thoracic kyphosis pre-operatively to final follow up (mean 4.0 ± 0.2 years) was higher in patients treated with 220 mm implants compared to 500 mm implants (220 mm: 7.5 ± 2.6° vs 500 mm: −4.0 ± 3.0°, p = 0.004). Use of low ROC (more curved) posterior distraction implants is associated with a significantly greater increase in thoracic kyphosis which likely led to a higher risk of developing clinically-significant PJK in EOS patients

Proximal junctional kyphosis (PJK) is defined as adjacent segment kyphosis >10° between the upper instrumented vertebrae and the vertebrae 2 levels above following scoliosis surgery. There are few studies investigating the predictors and clinical sequelae involved with this relatively common complication. Our purpose was to determine the radiographic predictors of post-op PJK and to examine the association between PJK and pain/HRQOL following surgery for AIS. The Post-Operative Recovery after Scoliosis Correction: Home Experience (PORSCHE) study was a prospective multicenter cohort of AIS patients undergoing spinal fusion surgery. Pre-op and minimum 2 year f/u scoliosis and sagittal spinopelvic parameters (thoracic kyphosis–TK, lordosis–LL, pelvic tilt-PT, sacral slope-SS, pelvic incidence-PI) were measured and compared to numeric rating scale for pain (NRS) score, SRS-30 HRQOL and to the presence or absence of PJK (proximal junctional angle >100). Continuous and categorical variables were assessed using logistic regression and binomial variables were compared to binomial outcomes using chi-square. 163 (137 females) patients from 8 Canadian centers met inclusion criteria. At final f/u, PJK was present in 27 patients (17%). Pre-op means for PJK vs No PJK: Age 14.1 vs 14.7yr; females 85 vs 86%; scoliosis 57±22 vs 62±15deg; TK 28±18 vs 19±16deg ∗, LL 62±11 vs 60±12deg, PT 8±12 vs 10±10deg, SS 39±8 vs 41±9deg, PI 47±14 vs 52±13deg, SVA −9±30 vs −7±31mm. Final f/u for PJK vs No PJK: Scoliosis 20±11 vs 18±8deg, final TK 26±12 vs 19±10deg∗, LL 60±11 vs 57±12deg, PT 9±12 vs 12±13deg, SS 39±9 vs 41±9deg, PI 48±17 vs 52±14deg, SVA −23±26 vs −9±32mm∗. Significant findings: Pre-op kyphosis >40deg has an odds ratio (OR) of 4.41 (1.50–12.92) for developing PJK∗. The presence of PJK was not associated with any significant differences in NRS or SRS-30. ∗denotes p<0.05. This prospective multicenter cohort of AIS patients demonstrated a 17% risk of developing PJK. Pre-op thoracic kyphosis >40deg was associated with the development of PJK; however, the presence of PJK was not associated with increased pain or decreased HRQOL

Neuromuscular scoliosis patients face rates of major complications of up to 49%. Along with pre-operative risk reduction strategies (including nutritional and bone health optimization), intra-operative strategies to decrease blood loss and decrease surgical time may help mitigate these risks. A major contributor to blood loss and surgical time is the insertion of instrumentation which is challenging in neuromuscular patient given their abnormal vertebral and pelvic anatomy. Standard pre-operative radiographs provide minimal information regarding pedicle diameter, length, blocks to pedicle entry (e.g. iliac crest overhang), or iliac crest orientation. To minimize blood loss and surgical time, we developed an “ultra-low dose” CT protocol without sedation for neuromuscular patients. Our prospective quality improvement study aimed to determine: if ultra-low dose CT without sedation was feasible given the movement disorders in this population; what the radiation exposure was compared to standard pre-operative imaging; whether the images allowed accurate assessment of the anatomy and intra-operative navigation given the ultra-low dose and potential movement during the scan. Fifteen non-ambulatory surgical patients with neuromuscular scoliosis received the standard spine XR and an ultra-low dose CT scan. Charts were reviewed for etiology of neuromuscular scoliosis and medical co-morbidities. The CT protocol was a high-speed, high-pitch, tube-current modulated acquisition at a fixed tube voltage. Adaptive statistical iterative reconstruction was applied to soft-tissue and bone kernels to mitigate noise. Radiation dose was quantified using reported dose indices (computed tomography dose index (CTDIvol) and dose-length product (DLP)) and effective dose (E), calculated through Monte-Carlo simulation. Statistical analysis was completed using a paired student's T-test (α = 0.05). CT image quality was assessed for its use in preoperative planning and intraoperative navigation using 7D Surgical System Spine Module (7D Surgical, Toronto, Canada). Eight males and seven females were included in the study. Their average age (14±2 years old), preoperative Cobb angle (95±21 degrees), and kyphosis (60±18 degrees) were recorded. One patient was unable to undergo the ultra-low dose CT protocol without sedation due to a co-diagnosis of severe autism. The average XR radiation dose was 0.5±0.3 mSv. Variability in radiographic dose was due to a wide range in patient size, positioning (supine, sitting), number of views, imaging technique and body habitus. Associated CT radiation metrics were CTDIvol = 0.46±0.14 mGy, DLP = 26.2±8.1 mGy.cm and E = 0.6±0.2 mSv. CT radiation variability was due to body habitus and arm orientation. The radiation dose differences between radiographic and CT imaging were not statistically significant. All CT scans had adequate quality for preoperative assessment of pedicle diameter and orientation, obstacles impeding pedicle entry, S2-Alar screw orientation, and intra-operative navigation. “Ultra-low dose” CT scans without sedation were feasible in paediatric patients with neuromuscular scoliosis. The effective dose was similar between the standard preoperative spinal XR and “ultra-low dose” CT scans. The “ultra-low dose” CT scan allowed accurate assessment of the anatomy, aided in pre-operative planning, and allowed intra-operative navigation despite the movement disorders in this patient population

Neuromuscular scoliosis patients face rates of major complications of up to 49%. Along with pre-operative risk reduction strategies (including nutritional and bone health optimization), intra-operative strategies to decrease blood loss and decrease surgical time may help mitigate these risks. A major contributor to blood loss and surgical time is the insertion of instrumentation which is challenging in neuromuscular patient given their abnormal vertebral and pelvic anatomy. Standard pre-operative radiographs provide minimal information regarding pedicle diameter, length, blocks to pedicle entry (e.g. iliac crest overhang), or iliac crest orientation. To minimize blood loss and surgical time, we developed an “ultra-low dose” CT protocol without sedation for neuromuscular patients. Our prospective quality improvement study aimed to determine:. if ultra-low dose CT without sedation was feasible given the movement disorders in this population;. what the radiation exposure was compared to standard pre-operative imaging;. whether the images allowed accurate assessment of the anatomy and intra-operative navigation given the ultra-low dose and potential movement during the scan. Fifteen non-ambulatory surgical patients with neuromuscular scoliosis received the standard spine XR and an ultra-low dose CT scan. Charts were reviewed for etiology of neuromuscular scoliosis and medical co-morbidities. The CT protocol was a high-speed, high-pitch, tube-current modulated acquisition at a fixed tube voltage. Adaptive statistical iterative reconstruction was applied to soft-tissue and bone kernels to mitigate noise. Radiation dose was quantified using reported dose indices (computed tomography dose index (CTDIvol) and dose-length product (DLP)) and effective dose (E), calculated through Monte-Carlo simulation. Statistical analysis was completed using a paired student's T-test (α= 0.05). CT image quality was assessed for its use in preoperative planning and intraoperative navigation using 7D Surgical System Spine Module (7D Surgical, Toronto, Canada). Eight males and seven females were included in the study. Their average age (14±2 years old), preoperative Cobb angle (95±21 degrees), and kyphosis (60±18 degrees) were recorded. One patient was unable to undergo the ultra-low dose CT protocol without sedation due to a co-diagnosis of severe autism. The average XR radiation dose was 0.5±0.3 mSv. Variability in radiographic dose was due to a wide range in patient size, positioning (supine, sitting), number of views, imaging technique and body habitus. Associated CT radiation metrics were CTDIvol = 0.46±0.14 mGy, DLP = 26.2±8.1 mGy.cm and E = 0.6±0.2 mSv. CT radiation variability was due to body habitus and arm orientation. The radiation dose differences between radiographic and CT imaging were not statistically significant. All CT scans had adequate quality for preoperative assessment of pedicle diameter and orientation, obstacles impeding pedicle entry, S2-Alar screw orientation, and intra-operative navigation. “Ultra-low dose” CT scans without sedation were feasible in paediatric patients with neuromuscular scoliosis. The effective dose was similar between the standard preoperative spinal XR and “ultra-low dose” CT scans. The “ultra-low dose” CT scan allowed accurate assessment of the anatomy, aided in pre-operative planning, and allowed intra-operative navigation despite the movement disorders in this patient population

Scoliosis is estimated to occur between 21–64% of patients with cerebral palsy (CP), where a subset of patients develops early onset scoliosis (EOS) before the age of ten. Traditional growth friendly (TGF) surgeries in the context of traditional growing rods have been shown to be effective in treating scoliosis in this population, however significant complication rates are reported. Currently, no studies have been done to examine the effect of novel growth friendly surgeries such as magnetically controlled growing rods (MCGR) on EOS in CP patients. The objective of this study is to compare MCGR with TGF surgeries in this patient population, specifically by evaluating radiographic measurements and risk of unplanned reoperations (UPRORs). Patients with EOS secondary to CP were prospectively identified from an international database, with data retrospectively analyzed. Scoliosis (primary curve), maximum kyphosis, T1-S1 and T1-T12 height were measured pre-operation, immediate post-operation, and at two-years follow-up. The risk and etiology of UPRORs were compared between MCGR and TGF. P < 0.05 was considered statistically significant for all analyses. Of the 120 patients that met inclusion criteria, 86 received TGF (age 7.5 ± 1.8 years; follow-up 7.0 ± 2.9 years) and 34 received MCGR (age 7.1 ± 2.2 years, follow-up 2.8 ± 0.5 years). Compared to TGF, MCGR resulted in significant improvements in maintenance of scoliosis correction (p=0.04). At final follow-up, UPRORs were 24% for MCGR (8/34 patients) and 43% (37/86 patients) for TGF (p=0.05). To minimize the influence of follow-up period, UPRORs within the first two years post-operation were evaluated: MCGR (21%, 7/34 patients) vs. TGF (14%, 12/86 patients; p=0.37). Within the first two years, etiology of UPROR as a percentage of all patients per group were deep infection (5% TGF, 6% MCGR), implant failure/migration (5% TGF, 9% MCGR), dehiscence (2% TGF, 3% MCGR), and superficial infection (1% TGF, 3% MCGR). The most common etiology of UPROR for TGF was deep infection and implant failure/migration and for MCGR was implant failure/migration. For patients with CP, at final follow-up, MCGR had superior maintenance of scoliosis correction; however, there was no difference in risk of UPROR within the first two years post-operatively (21% MCGR, 14% TGF)

Introduction. Pedicle Subtraction osteotomy (PRO) in correction of severe spinal deformities is well established. Prospective analysis of its efficacy in complex spinal deformities is sparse in literature. Aims and objectives. To assess the role of PRO in correction of uniplanar and multiplanar spinal deformity and to assess the role of revision PRO in failed corrections. Material and methods. 50 patients were operated between 1996-2007 and followed up for 2 years (2-6). 27 had uniplanar kyphosis (60-128 degrees) and kyphoscoliosis was seen in 10. Failed corrections were seen in 11 uniplanar and 2 multiplanar deformities. The average pre-operative kyphosis and sagittal balance was 78.7 degrees and 22 mm (7-30) respectively. Scoliotic deformity ranged from 97-138 (average 108 degrees) and the coronal imbalance from 10-55 (average 24mm). Deformity distribution was upper dorsal 5, mid dorsal 22, dorso-lumbar 18 and lumbar 5. A single posterior approach sufficed in 47 cases while 3 required an anterior approach for reconstruction. 13 patients had pre-operative neurological deficit (bedridden 10, ambulatory 3). The average surgical time required was 300 minutes and blood loss was 800cc. The anterior defect reconstructed averaged 16.5mm (5-28). Results. Pulmonary complications occurred in 8 (21%), (embolism 1, pneumonia 2, hypoxia 5). Wound infection required debridement in 3 (8%). Failed corrections were seen in 10 (3 out of 37 in our series, 8%) due to failure of construct 2, severe disease 2, infection (active 2, quiescent 4). Neurological deterioration occurred in 1(2%), medial pedicle wall perforation. 12 patients regained ambulation (independent 7, support 5). Post-operative kyphosis and sagittal balance was 36.5 (10-108) and 10mm (5-20) respectively. Average correction was: sagittal 46.4%, coronal 37.5% and revisions 58%. The correction of kyphosis and sagittal balance was statistically comparable between primary and revision cases (p >0.05). Conclusions. PRO offers an excellent single stage decompression and controlled correction of kyphosis

Thoracic kyphosis increases with age. The resultant increase in compression forces on the anterior vertebral bodies leads to further kyphotic deformity and, an increased likelihood of vertebral collapse. This study aimed to determine the relative efficacy of two therapeutic strategies commonly used to treat hyperkyphosis. 69 subjects (26 male: 43 female) were randomised into 4 groups: strengthening, postural re-education (PEd), both and control. The strengthening group attended a gym 3 times a week for 12 weeks to perform seated extension exercises. The PEd group had 3 physiotherapy sessions within a 12 week period in which they received postural assessment and a home exercise programme. The combined group received both interventions while the control group received neither. Outcome measurements were assessed at baseline and 12 weeks. They included static (inclinometer) and 6-hour angular measurements (using flexible electrogoniometer (FEG)) and physical function tests. There were no significant differences between the marginal means of the angular measurements for any of the intervention groups. However, the group which received both interventions demonstrated reduced kyphosis as measured by the FEG angles (apex of the curve between T3 and T11), while the strengthening group showed reduced inclinometer angles (between T1 and T12). The strengthening group showed improvement in back extensor strength (BES) (0.6 +/− 0.2 N/kg, p < 0.01), time to walk 10 metres (−0.3 +/− 0.6 s, p < 0.05), and time to stand and sit 5 times (−0.9 +/− 0.6 s, p < 0.05). However, there was no relationship between change in BES and change in kyphotic angle. The PEd group showed the greatest improvement in the timed up and go test but this was not significant. Improvement in inclinometer angle over the 12 weeks was associated with degree of kyphosis at baseline (upright inclinometer r = −0.47, p=0.0001) but this relationship was not apparent in the FEG measurements. Both the FEG and inclinometer angles showed a marked decrease in degree of improvement in subjects aged >70. (50/50). A combination of strengthening and PEd was most effective at reducing hyperkyphosis. BES was improved with resisted strengthening but not with home-based postural exercises. However, increased BES was not associated with decreased kyphosis. Larger baseline kyphosis was associated with greater angular improvement. Subjects aged >70 were less likely to improve

Purpose. Management of early onset scoliosis (EOS) can be very challenging. Surgery is indicated when orthotics and casting fail. Growing rod instrumentation has become an effective approach in controlling the deformity while allowing spinal growth. However, as with any surgery, there are known complications including failure of the proximal foundation. We analyzed our patients who underwent growing rod instrumentation and identified factors that were correlated with proximal foundation failure. Method. Our Pediatric Orthopaedic Spine Database (1992–2010) was reviewed for all patients who underwent growing rod instrumentation. Sixty-six patients with EOS were identified and divided into two groups: Group 1 – proximal foundation failure; and Group 2 – no incidents of proximal failure. The two groups were evaluated for differences in age, sex, weight, upper vertebral level in construct, presence of apical fusion, and pre-operative curve magnitude. Results. Eight of the 66 patients (12%) had proximal foundation failure. When comparing Group 1 and Group 2, only age, pre-operative kyphosis, and presence of apical fusion were significant differences between the two groups. The mean age of Group 1 patients was 4.9 years (range, 2.6 to 9.2 years) and the mean age of Group 2 patients was 7.5 years (range, 2.4 to 11.6 years) (p <0.006). The mean pre-operative kyphosis in Group 1 was 71 degrees compared to 50 degrees in Group 2 (p=0.049). Among the 12 patients with apical fusion, four (33%) had proximal failure. The presence of apical fusion was also a significant difference between the groups (p=0.003). Linear regression demonstrated a significant correlation between kyphosis and failure (k=0.005, p-value 0.016) as well as age and pullout (k=−0.005, p-value <0.01). Conclusion. Our data indicates that younger patients with increased pre-operative kyphosis are at a higher risk for proximal failure of their growing rods resulting in increased incidence of unplanned surgeries. The presence of an apical fusion was also correlated to increased failure rates possibly due to stress at the proximal construct. Further research is needed to determine if stronger constructs decrease the pullout rate in the at-risk patients

Decision-making regarding operative versus non-operative treatment of patients with thoracolumbar burst fractures in the absence of neurological deficits is controversial, and evidence from trials is sparse. We present a systematic review and meta-analysis of randomised trials comparing operative treatment to non-operative treatment in the management of thoracolumbar burst fractures. With the assistance of a medical librarian, an electronic search of Medline Embase and Cochrane Central Register of Controlled trials was performed. Trials were included if they: were randomided, had radiologically confirmed thoracolumbar (T10-L3) burst fractures, had no neurological deficit, compared operative and non-operative management (regardless of modality used), and had participants aged 18 and over. We examined the following outcomes: pain, using a visual analogue scale (VAS), where 0=no pain and 100=worst pain; function, using the validated Roland Morris Disability Questionnaire (RMDQ); and Kyphosis (measured in degrees). Two randomised trials including 79 patients (41 operative vs. 38 non-operative) were identified. Both trials had similar quality, patient characteristics, outcome measures, rates of follow up, and times of follow up (mean=47 months). Individual patient data meta-analysis (a powerful method of meta-analysis) was performed, since data was made available by the authors. There were no between-group differences in sex, level of fracture, mechanism of injury, follow up rates or baseline pain, kyphosis and RMDQ scores, but there was a borderline difference in age (mean 44 years in operative group vs. 39 in non-operative group, p=0.046). At final follow up, there were no between group differences in VAS pain (25 in operative group vs. 22 non-operative, p=0.63), RMDQ scores (6.1 in operative group vs. 5.8 non-operative, p=0.85), or change in RMDQ scores from baseline (4.8 in operative group vs. 5.3 non-operative, p=0.70). But both kyphosis at final follow up (11 degrees vs. 16 degrees, p=0.009) and reduction in kyphosis from baseline (1.8 degrees vs. -3.3 degrees, p=0.003) were better in the operative group. Operative management of thoracolumbar burst fractures appears to improve kyphosis, but does not improve pain or function

Intrathecal morphine (IM) is a common adjunct in paediatric spinal deformity surgery. We previously demonstrated with idiopathic scoliosis it provides safe and effective analgesia in the immediate postoperative period. This study represents our 25 year experience with IM in all diagnostic groups. Our prospective Pediatric Orthopaedic Spine Database (1993–2018) was reviewed to identify all patients undergoing spinal deformity surgery who received IM and who did not. Patients 21 years of age or less who had a posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI), and received 9–19 mcg/kg (up to 1 mg) of IM were included. Early onset scoliosis surgical patients were excluded. We assessed demographics, pain scores, time to first dose of opioids, diagnoses, surgical time, paediatric intensive care unit (PICU) admission and IM complications (respiratory depression, pruritus, nausea/ vomiting). There were 986 patients who met inclusion criteria. This included 760 patients who received IM and 226 who did not. IM was not used for short procedures (< 3 hrs), respiratory concerns, unsuccessful access of intrathecal space, paraplegia, and anesthesiologist decision. Both groups followed the same strict perioperative care path. The patients were divided into 5 diagnostic groups (IM / non IM patients): idiopathic (578/28), neuromuscular (100/151), syndromic (36/17), and congenital scoliosis (32/21) and kyphosis (14/9). Females predominated over males (697/289). The first dose of opioids after surgery was delayed for a mean of 10.6 hrs in IM group compared to 2.3 hrs in the non-IM group (p=0.001). The postoperative pain scores were significantly lower in the IM groups in the Post Anesthesia Care Unite (p=0.001). Only 17 IM patients (2%) were admitted to the PICU for observation secondary to respiratory depression, none required re-intubation. None of the IM group were re-intubated. Forty-nine patients (6%) experienced pruritus in the IM group compared to 4 of 226 patients (2%) in the non IM group. There were 169 patients (22%) of the IM patients and 21 patients (9%) of the non IM had nausea and vomiting postoperatively. Three patients (0.39%) had a dural leak from the administration of IM but did not require surgical repair. There were no other perioperative complications related to the use of IM. There were no significant group differences. Pre-incision IM is a safe and effective adjunct for pain management in all diagnostic groups undergoing spinal surgery. The IM patients had lower pain scores and a longer time to first administration of post-operative opioids. Although there is an increased frequency of respiratory depression, pruritus, and nausea/vomiting in the IM group, there were no serious complications

Introduction. From 2004 to 2015, elective lumbar fusions increased by 62% in the US. The largest increases were for among age 65 or older (139% in volume) and scoliosis (187%) [1]. Age is a well known factor of osteoporosis. The load-sharing may exceed the pedicular screws constructs in aging spine and lead to non-union and re-do. Surgical options may increase the screw purchase (e.g.: augmentation, extensions) at supplementary risks. Pedicular screw are known to cause vascular, nerve root or cord injuries. Facing these pitfalls, the surgeon's experience and rule of thumbs are the most deciding factors for the surgical planning. The aim of this study is to assess the accuracy of a patient specific tool, designed to plan a safe pedicular trajectory and to provide an intraoperative screw pullout strength estimate. Materials and Methods. Clinical QCT were taken for nine cadaveric spines (82 y. [61; 87], 6 females, 3 males). The experimental maximum axial pullout resistance (FMax) of twenty-seven pedicular screws inserted (nine T12, nine L4 and nine L5) was obtained as described in a previous study [2]. A custom 3D-WYSIWYG software simulated a medio-lateral surgical insertion technique in the QCTs coordinates reference, respecting the cortical walls. Repeatable density, morphometric and hardware parameters were recorded for each vertebrae. A statistical model was built to match predictive and experimental data. Preliminary results. Experimental FMax(N) were [104;953] (359 ±223). A further displacement of 1,81mm ±0,35 halved the experimental FMax. Predictive FMax(N) were [142;862] (359 ±220). A high positive correlation between experimental and predictive FMax was revealed (Pearson, ρ = 0.93, R2 = 0.87, p < .001, figure 1). Absolute differences ranged between 3N and 177N. Discussion. A high screw purchase in primary fixation is paramount to achieve spine surgical procedures (e.g.: kyphosis, scoliosis) and postoperative stability for vertebrae fusion. High losses of screw purchase by bone plastic deformation, begin with tiny pullouts. Theses unwanted intraoperative millimetric over-displacements are hard to avoid when monitoring at the same time tens of screws surrounded by bleedings. This advocates for including predictive FMax for each implantable pedicular screw in the surgical planning decision making process to prevent failures and assess risks. For the first time, this study presents an experimentally validated statistical model for FMax prediction with a safe trajectory definition tool, including patients’ vertebrae and hardware properties and referring to the patient's clinical 3D quantitative imagery. The model was able to differentiate between bone quality and vertebrae variations. More extensive model validation is currently ongoing to interface with robotics & navigation systems and to produce meshes for 3D printing of sterilizable insertion guides

Introduction. Anterior reconstruction has the advantage of conferring immediate stability to the cervico-thoracic junction. Aims and objectives. Assess clinical and radiological outcome in cervico-thoracic kyphosis treated with anterior reconstruction. Material and methods. 62 cases were treated with anterior reconstruction from 1996-2007. Minimum follow-up was 2years (2-6). Indications included tuberculosis (45), dysplastic(10), neoplastic (3) and traumatic (4). Average age was 28.6 years (13-72 years). Average pre-operative kyphosis was 26.4 degrees (5-84). Patients were grouped as long-neck (35) and short-neck (27) according to classification proposed by Bapat and Laheri. The caudal normal vertebra (CNV) matched on plain radiology and MRI in 40 (64.51%). In 22 level of fixation was extended due to poor bone mass in the adjacent vertebral body (caudal 17, cranial 5). Pre-operative neurological deficit was seen in 57 (91.3%) and average Nurick's grade was 3.8 (0-5). Results. 32 long-neck patients required strap-muscle tenotomy to expose the CNV. In 3(9.3%) manubriotomy was required (large neck girth 1, thyroid goitre 2). 26 short-neck patients required manubriotomy for plate placement. In 42 (67.8%) patients a standard anterior cervical plate was used. In 22 locking plate was used. Commonest cranial and caudal vertebrae instrumented were C7 (32) and T2 (20) respectively. Post-operative kyphosis averaged 14.68 degrees (0-78) and correction averaged 11.72 degrees. Average post-operative Nurick's grade was 2.8. One patient with fracture dislocation of T1-T2 and traumatic oesophageal rupture died. In 1 the implant loosened and was revised with posterior construct. In 1, screw loosening was observed but implant position remained unaltered. 2 patients had recurrent laryngeal palsy. Iatrogenic pleural rent occurred in 2 patients. Transient dysphagia was noticed in 12. The scar hypertrophy was seen in 30(48.38%). The loss of correction averaged 2.3mm (0-4mm) at the final follow-up. Conclusion. Anterior reconstruction allows excellent reconstruction of cervico-thoracic junction obviating need for a posterior construct

The progressive kyphosis and pain in patients with acute thoracolumbar burst fractures treated conservatively so as the recurrent kyphosis after posterior reduction and fixation were associated to disc collapse rather than vertebral body compression. It depends on redistribution of the disc tissue in the changed morphology of the space after fractures of the endplate. The aim of this study is to evaluate the safety and the efficacy of balloon kyphoplasty with calcium phosphate, alone or associated to short posterior instrumentation, in the treatment of acute thoracolumbar burst fractures. Eleven fractures in ten consecutive patients with an average age of 48 years who sustained acute thoracolumbar traumatic burst fractures without neurological deficits were included in this study. The fractures were A1.2 (3), A3.1 (4) and A3.2 (4), according to AO classification. In 7 fractures (A1.2 and A3.1) the kyphopasty was performed alone in order to make the most of efficacy in fracture reduction, anterior and medium column stabilization and, as much as possible, segmental kyphosis correction. In the A3.2 fractures (4), that are unstable, the kyphoplasty was associated to a short posterior instrumentation. To avoid the PMMA long run complications in younger patients, we used a calcium phosphate cement. VAS, SF-36, Roland-Morris questionnaire (RMQ) and Oswestry low back pain disability questionnaire (ODQ) were used to evaluate pain, state of health, functional outcomes and spine disability. To the average follow-up time of 15.5 months (range 8–31) we did not observe statistically significant differences in 7 of 8 SF-36 domains in comparison to general healthy population of same sex and age. At the same follow-up, the spine disability questionnaire showed a functional restriction of 18% (ODQ) and 29,6% (RMQ) being 100% the maximum of disability. No bone cement leakage, no implant failure and no height correction loss were observed in any case. Our data confirm the safety and the efficacy of ballon kyphoplasty with calcium phosphate in the treatment of acute thoracolumbar burst fractures. In this way we can reduce the possible complications resulted from discal space collapse and obtain an early functional restoration. When performed alone, this mini invasive surgical technique offer the advantage of almost immediate return to daily activities. When associated to posterior instrumentation, it decreases the long run complications and allows to reduce the number of stabilized levels, maintaining, in part, the thoracolumbar junction movement

Background:. Severe kyphosis in myelomeningocoele patients results in seating problems, early satiety and ultimately pressure sores over the prominence. Kyphectomy and sagittal correction can improve these morbidities. Aim:. To evaluate the outcome of kyphectomy surgery in meningomyelocoele children. Methods:. A retrospective review was performed of a single surgeon series of paediatric myelomeningocele patients who underwent kyphectomy surgery. All the patients had posterior fusion, employing pedicle screws and sub laminar wiring. All the posterior fusions extended to the pelvis either to include S1 or the ilium. Prior to surgery, three children had open wounds over the apex of the deformity. Despite prone nursing, these failed to heal. These were closed primarily intra-operatively without the requirement of flaps. Results:. Seven children (four males, three females) were identified with an average age of 9.5 (8–13) years. The kyphosis was corrected from a mean range of 110° (88°–180°) to post-operative range of 5°–45°. The operative time averaged 240 min (165–284 min) with an estimated blood loss average of 957 ml (500–2550 ml). All the patients recovered well and no short-term complications were experienced except one transient CSF leak intra operatively. Two patients presented with sub-acute delayed infection requiring removal of instrumentation once the spine had fused. There was one case of instrumentation failure. All patients had improved wheel chair seating. Conclusion:. Kyphectomy in myelomeningocele is an infrequently required procedure which is effective in sagittal correction and improved seating with an acceptable complication rate

We hypothesised whether MIS techniques confer any benefit when treating thoracolumbar burst fractures. This was a prospective, non-randomised study over the past seven years comparing conservative (bracing:n=27), conventional surgery (open techniques:n=23) and MIS techniques (n=21) for stabilisation and correction of all thoracolumbar spinal fractures with kyphosis of >20. 0. , using Camlok S-RAD 90 system (Stryker Spine). All patients previously had normal spines, sustained only a single level burst fracture (T12, L1 or L2) as their only injury. Age range 18–65 years. All patients in both operatively treated groups were corrected to under 10. 0. of kyphosis, posteriorly only. All pedicle screws/rods were removed between 6 months and 1 year post surgery to remobilise the stabilised segments once the spinal fracture had healed, using the original incisions and muscle splitting/sparing techniques. Patients were assessed via Oswestry Disability Index (ODI) and work/leisure activity status 1 year post fracture. The conservatively treated group fared worst overall, with highest length of stay, poorest return to work/activity, and with a proportion (5/27) requiring later intervention to deal with post-traumatic deformity. 19/27 returned to original occupation, at average 9 months. ODI 32%. Conventional open techniques fared better, with length of stay 5 days, most (19/23) returning to original work/activity, and none requiring later intervention. Average return to work was at 4 months. ODI 14%. MIS group fared best, with shorter length of stay (48 hours), all returning to original work/activity at average 2 months, and none requiring later intervention. ODI negligible. There was no loss of correction in either operatively treated groups. The Camlok S-RAD 90 system is a powerful tool for correction of thoracolumbar burst fractures, and maintains an excellent correction. MIS techniques provide the best outcomes in treating this group of spinal fractures, and offer patients the best chance of restoration to pre-fracture levels of activity

Purpose. To evaluate whether continuous training and education of posture can help children to improve kyphosis. Method. A smart harness consisting of a tight-fitting harness and a posture sensing system was developed to measure kyphosis and to provide vibratory feedback during daily activities. The posture sensing system consisted of two sensor units and both units contained a 3-axis accelerometer and a 2-axis gyroscope to calculate the orientation. The dimensions and weight of each unit were 55 mm x 35 mm x 15 mm and 25g, respectively. One unit served as a master (placed at the T3 vertebral level) and the second unit served as a slave (placed at the T12 level) and they communicated wirelessly. The master unit calculated the kyphotic angle, similar to the vertebral centroid method but based on the sagital profile, and provided the vibratory feedback. One volunteer wore the unit and performed different postures and activities (walking, sitting, bending and sudden change from sitting to walking) in a gait analysis laboratory. The posture sensing system was sampled at 30Hz and a gait analysis 8-camera system was sampled at 60Hz. The kyphotic angles captured by the smart harness and camera system were compared. After this validation, the system was tested by 5 normal subjects (M, 25 10 years old) 3 hours per day for 4 consecutive days. For the first 2 days there was no feedback and the last 2 days there was feedback. The system took a sample every 30 seconds. When an undesirable posture was detected, the system switched to a fast sample mode at which time the system took ten measurements with a sample rate of 10 Hz for 1 second to further validate the measured kyphotic angle. These 10 measures were averaged to avoid feedback for postures that lasted only for a very short period of time. Posture orientation data was stored in the sensing unit memory and downloaded for outcomes evaluation. Results. Compared with the gait analysis camera system, the differences in the kyphotic angle during static and dynamic activities were 1.6 1.2, and 3.5 1.9 degrees, respectively. The largest error was 6.8 degrees which occurred during a dramatic change in posture during dynamic activities. The baseline data from the first 2 days (without feedback) showed the kyphotic angle was 48 12 degrees, during which time all subjects were working in front of a computer. The feedback days showed a slight improvement of kyphotic angles from day 1 to day 2, from 45 11 to 42 8 degrees, respectively. There was 12% improvement on day 2 when compared with the baseline data. Conclusion. This study showed the kyphotic angle could be fairly accurately measured using the smart harness. The kyphotic angle had a slight improvement when feedback was provided, however a longer clinical trial will be required to determine how lasting the effect will be

Purpopse. Few Cervical Total Disc Replacement (TDR) devices are engineered to address both the Center of Balance (COB) and the Center of Rotation (COR) of the cervical motion segments. The COB is the axis in the intervertebral disc through which the axial compressive load is transmitted. TDRs placed posterior of this point tend to fall into kyphosis while devices placed anterior of this point tend to fall into lordosis. Thus from a “balancing” point of view the ideal placement would be at the COB. However, the COR position has been shown to be posterior and inferior to the disc space. It has also been shown that constrained devices tend to lose motion when there is a mismatch between device and anatomic centers. Mobile core devices may be placed at the COB since their unconstrained rotations and translations allow for the device COR to follow the anatomic COR, but they rely heavily on the facet joints and other anatomic features to resist the paradoxiacal motion. The TriLobe cervical TDR (Figure 2) was engineered for both the COB and COR. The purpose of this study was to compare the 3D kinematic and biomechanical performance of the TriLobe to a ball and trough(BT) cervical TDR in an augmented pure moment cadaveric study to find the ideal AP implant placement. Materials and methods. Specimen were CT imaged for three-dimensional reconstruction. Visual, CT, and DEXA screening was utilized to verify that specimens are free from any defects. Specimens were prepared by resecting all nonligamentous soft tissue leaving the facet joint capsules and spinal ligaments intact. C2 and T1 were potted to facilitate mounting in the testing apparatus (7-axis Spine Tester, Univ. of Utah, Salt Lake City, UT). OptoTRAK motion tracking flags were attached to each vertebra including C2/C3 and T1 to track the 3D motion of each vertebra. •. Specimens C2–T1. •. Treatment Level C5–C6. •. Insertion of fixture pins under fluoro. •. Load Control Testing to 2.5Nm in FE, LB, AR at 0.5Hz. •. 15 Pre-cycles in load control in FE / LB / AR (2.5Nm). •. Test implants in load control in FE / LB / AR to 2.5Nm for 4 cycles with data recorded for all cycles. Results. [Results Table - Figure 1]. Discussion. This study showed that the TriLobe had better control of motion compared to the ball and trough both in ROM and varibility for FE, LB, and AR. The TriLobe had better control of limiting kyphosis over the ball and trough by 41% of the flexion motion. The neutral zone slope, an measure for device stability, showed that the TriLobe was 51% more stable than the BT. AP placement of devices showed there was a general trend of decreasing stability from anterior to posterior placement; however, statistical significance was not established

Introduction. Pelvic posterior tilt change (PPTC) after THA is caused by release of joint contracture and degenerative lumbar kyphosis. PPTC increases cup anteversion and inclination and results in a risk of prosthesis impingement (PI) and edge loading (EL). There was reportedly no component orientation of fixed bearing which can avoid PI and EL against 20°PPTC. However, dual mobility bearing (DM) has been reported to have a large oscillation angle and potential to withstand EL without increasing polyethylene (PE) wear against high cup inclination such as 60∼65°. Objective. The purpose of this study was to investigate the optimal orientation of DM-THA for avoiding PI and EL against postoperative 20°PPTC. Methods. Our study was performed with computer tomography -based three-dimensional simulation software (ZedHip. LEXI co. Japan). The CT data of hip was derived from asian typical woman with normal hips. Used prosthesises were 50mm cup and 42mm outer head of modular dual mobility system and Accolade II 127°(stryker). Femoral coordinate system was retrocondylar plane with z-axis from trochanteric fossa to intercondylar notch. Cup orientation was described as anatomical definition. The safe zone was calculated by the required hip range of motion which was defined as 130°flexion, 40°extension, 30°external rotation, and 50°internal rotation with 90°flexion and the maximum inclination of DM cup which was 60°in consideration of withstanding EL. Cup orientations withstanding 20°PPTC were defined as the primary cup orientation which changes consistently within the safe zone with the match of 20°PPTC. And among them cup orientation with lowest inclination was defined as the optimal cup orientation. result. The optimal orientations could be identified only within stem anteversion from 15°to 40°. The relationship between the optimal cup orientation and stem anteversion could be automatically identified. The correlation between stem anteversion and cup anteversion was linearly distributed and could be expressed as an approximated line of the formula that (stem anteversion)+(cup anteversion)=36.8. And likewise the relationship between stem anteversion and cup inclination was curved-linerly distributed and could be expressed as an approximated curved line of the formula that (cup inclination)=0.04(stem anteversion). 2. 2.18(stem anteversion)+74.8. Cup orientation calculated by the Widmer's combined anteversion theory is easily deviated from the safe zone by PPTC. The optimal cup orientation calculated in this study could be set more inclination and retroversion than it calculated by the Widmer's theory in contribution of large oscillation angle and admissibility of high inclination cup setting of DM. Therefore it could be possible to withstand 20°PPTC. Conclusion. Performing THA with considering postoperative PPTC is necessary for good long term outcome without dislocation and PE wear. The solution for 20°PPTC after THA is to apply dual mobility bearing and the formula of combined orientation theory calculated in this study

Among the extra pulmonary forms of tuberculosis (TB), the osteoarticular localization has been detached in 1–2% of cases. In 30% of these children either a pulmonary and extra-pulmonary localization was found. The diagnosis of skeletal TB is often insidious due to variable signs and symptoms. The medical records of children admitted to our center between 2006 and 2013 due to skeletal TB were evaluated. All patient underwent TB skin test, IGRA test, chest X-ray and focused imaging tests. In the complicated forms of osteoarthritis the infected material drained spontaneously or surgically was analyzed for Mycobacterium Tuberculosis (MT) detection and culture. In patients with pulmonary localization gastric aspirates or sputum analysis was performed. Nine patients met the inclusion criteria. The median age at diagnosis was 7 (range 2–13) years. All patients presented with local osteoarticular symptoms and 4 of them had fever. In five cases there was a preceding history of minor trauma. Three patients had a case of TB in the family. Four patients had a spinal localization, three hips and two ankles. ERS and CRP values were altered in 7 and 4 patients respectively. All patient underwent radiography, bone three phase scintigraphy and a MRI. The diagnosis of tuberculosis was confirmed by histopathological examination of bone biopsy in 6 (66%) cases. The skin test and the IGRA test were positive in all patients. The chest X-ray showed a pulmonary localization in 3 cases that had positive gastric aspirate or sputum. All patients were treated with isoniazid, rifampicin pyrazinamide and ethambutol. In 3 patients Linezolid or Ciprofloxacin was also associated. The follow-up had an average value of 34 months. Sequelae were reported in 7 patients (limping in 5 cases, severe kyphosis in 2 cases). Owing to its low incidence in developed countries, the diagnosis ot TB is often delayed for months to years. Additionally, we highly recommend taking a biopsy of the site of suspected infection because an early diagnosis is the key to successful treatment