Utility of Asymmetric Multilevel Pontes Osteotomy in Ankylosing Spondylitis with Scoliosis using Ultrasonic Bone Scalpel: Case Report.

Introduction: Ankylosing spondylitis is a spondyloarthropathy that commonly involves the axial skeleton with predilection to the sacro-iliac joints and spine. The disease frequently results in a smooth globular kyphotic deformity of the spine; however, a coronal plane scoliotic deformity is extremely rare. We present a unique case of scoliotic deformity in a patient diagnosed with ankylosing spondylitis. To the best of our knowledge, following a review of the literature, this appears to be the first report of this kind. Case Report: A 23-year-old male patient presented with chronic back pain, stiffness, and a truncal shift of the body. He had a rigid left-sided thoracolumbar curve measuring 41° with a coronal imbalance of 3.6 cm. We present a case report on scoliosis deformity correction performed with a four-level asymmetric pontes osteotomy using a bone scalpel with excellent correction of the scoliotic deformity that was well maintained at 2-year follow-up. Conclusion: Scoliosis in ankylosing spondylitis has not been documented in literature. We report the complete correction of the deformity, which is well maintained at the 2-year follow-up.

Cervical Schwannoma camouflaged by cervical intervertebral disc prolapse-A case report.

INTRODUCTION: Cervical prolapsed intervertebral disc is one of the common conditions causing cervical myeloradiculopathy. Anterior Cervical Discectomy and Fusion (ACDF) is the standard line of management for the same. Intradural neurogenic origin tumors are relatively rare and can present with features of myeloradiculopathy. Radiological imaging plays important role in diagnosis of such pathologies. CASE REPORT: We report a patient with C5-6 cervical disc prolapse that presented with radiculopathy symptoms in the right upper limb, which was refractory to conservative care. He underwent a C5-6 ACDF and reported complete relief from symptoms at 4 weeks. He developed deteriorating symptoms over the next 10 weeks and presented at 14 weeks follow-up with severe myeloradiculopathy symptoms on the left upper limb with upper limb weakness. A fresh MRI identified an intradural extramedullary tumor with cystic changes at the index surgery level. This was treated with tumor excision and histopathology confirmed a diagnosis of schwannoma. Simultaneous presence of cord signal changes with disc herniation obscured the cystic schwannoma which became apparent later on contrast enhanced MRI imaging. CONCLUSION: Careful review of preoperative imaging and contrast MRI study may help in diagnosing cystic schwannomas with concomitant cervical disc herniations that have cord signal changes.

"Critical pedicle wall" breaches analysis in complex spinal deformity using O-arm navigation.

Background: Free-hand and fluoroscopic-guided pedicle screw placement has been associated with higher rates of pedicle breaches (frequency range 15-40% especially in deformed pedicles). Neurological complications are more "critical" (i.e., frequent and significant) with medial and inferior pedicle-wall breaches due to the proximity of the neural elements. Here, we analyzed the effectiveness of O-arm navigation in minimizing "critical" pedicle wall breaches and their complications in 21 complex spinal deformity cases. Methods: Twenty-one complex spinal deformity cases were prospectively managed with O-arm-navigated posterior-instrumented fusions. Preoperative assessment included; evaluation of the type of scoliosis, the magnitude of the deformity, and the anatomy of the pedicles - (i.e., classified using Watanabe et al.). The O-arm was used to confirm and grade both the intraoperative and postoperative location of screws. Other variables analyzed included; duration of surgery, estimated blood loss, complications, and radiation exposure. Results: In 21 patients, 259 (63.45%) of 384 pedicles were instrumented; we observed 22 of 259 pedicle screw breaches. Significant (>2 mm) breaches were observed in two medial and one inferior wall cases that required revision; the overall biomechanically significant screw breach rate was (3/259) 1.2% with an accuracy rate of 98.8%. Pedicle screw placement resulted in another 14 nonsignificant (<2 mm) breaches; ten were medial and four involved the inferior wall. As anterior, lateral, and "in-out-in" trajectory pedicle screws beaches were nonsignificant, they were not included in our analysis. Conclusion: O-arm navigation decreased the incidence of medial and inferior (i.e., >2 mm "critical") pedicle screw breaches applied in 21 patients with deformed pedicles due to scoliosis. Further, the O-arm minimized the operating time, decreased the estimated blood loss, and reduced the incidence of complications.

Learning curve across 2000 thoracolumbar pedicle screw placements using O-arm navigation: technical difficulties and their solutions.

INTRODUCTION: Instrumentation using the intraoperative O-arm navigation technique appears safer than its predecessor techniques. However, only a handful of surgeons often used navigation during spinal surgeries. Too many operative glitches and unreliable navigation accuracy were the important reasons cited even by experienced surgeons for not using spinal navigation. We have studied the accuracy of pedicle screw placement during the learning curve and beyond it. We have also discussed in detail the intricacies of the technique and solutions to the difficulties encountered using spinal navigation. MATERIALS AND METHODS: A total of 2000 thoracolumbar pedicle screws have been placed in the 324 spine surgeries meeting the inclusion and exclusion criteria included in this retrospective study. We have divided 2000 pedicle screw placements into consecutive groups of 200 each. We have compared these groups for the accuracy of screw placement with the surgeon's experience. RESULTS: The accuracy of pedicle screw placement using the "in-versus-out" grading system in group 1 was 85.5% which significantly increased in group 2 to 93.5% (p-value: 0.0099), and thereafter, there was a nonsignificant increase in subsequent groups with the graph achieving the shape of a plateau. CONCLUSION: Surgeons should learn the correct principles of the technique of O-arm navigation to prevent the loss of accuracy and place pedicle screws with high accuracy. There is a learning curve of around 30-35 surgeries or 200 pedicle screw placements to acclimatize with the technique of O-arm navigation and learn its principles.

What does a department need to get involved in clinical trials?

Clinical trials are conducted to evaluate the usefulness of a drug, medical treatment, surgical intervention, radiological procedure, behavioral intervention, or preventive health care strategy. Clinical trials are challenging, time-consuming, and need careful planning and execution. There are certain requirements for an academic unit to be ready for conducting quality research, especially clinical trials. These include logistical concerns, infrastructure, appropriately trained human resources, conformity with ethical compliances and regulatory compliances as per the laws governing the respective geographical regions. Infrastructure requirements include research division space, robust data archival system, archival of imaging data, laboratory services, information technology division and facilities for the appropriate consenting process. Human resources such as principal investigators, data managers, clinical research assistants and biostatisticians are needed to execute the clinical trial as per the study design. Adherence to ethical and regulatory standards; during the conduct of the clinical trial are imperative. Strict compliance with prevailing governing laws in the country is a prerequisite for a department to get involved in clinical trials. The department also needs to put in place an institutional ethics committee; the composition of which is often governed by regulatory laws. The ethical aspects of the trial undergo a formal scrutiny by an Institute ethics committee that ensures quality care to the patient, and safeguards the patient's rights and privileges. The academic unit of any department forms the core for possible research and pursuit of clinical trials. A department with rich clinical experience and expertise in the filed aids in the execution of quality research. The academic department must consider grant writing and multiple center collaborative research projects in due course of time to further enhance the quality of clinical trials and research output.

Utility of selected sequence MRI imaging of the axial skeleton in the diagnosis of axial spondyloarthritis.

Background: Whole body MRI has been used to evaluate inflammatory lesions associated with axial spondyloarthritis (SpA). These sequences are extensive, time consuming and add to the cost of the investigation. We aimed to determine the utility of selected sequence MRI imaging of the axial skeleton including spine, pelvis and sacroiliac (SI) joints to identify features of (SpA). Methods: A retrospective study was conducted on 76 patients diagnosed with SpA that underwent a selective sequence MRI imaging of the axial skeleton. The MRI were reported by two musculoskeletal trained radiologists were reviewed. The MRI sequences included whole spine sequences of sagittal STIR (short tau inversion recovery), T1 weighted and T2 weighted sequences. Coronal STIR and T1 weighted images were studied for SI joints and pelvis. The MRI were assessed based on the guidelines outlined by the Assessment of SpondyloArthritis International Society (ASAS) for features of spondylitis, spondylodiscitis, enthesitis, synovitis, capsulitis, bone marrow edema, fatty marrow replacement, erosions and bony ankylosis. Inflammatory lesions were documented in the spine, sacroiliac, facet, hip and costovertebral joints. Results: The mean scan duration was 28 min. SI joint involvement was noted in 74 (97.3%) of patients. The other most prevalent findings were spondylitis in 44 (57.8%) patients, costovertebral joint involvement in 31 (40.7%), facet joint lesions in 32 (42.1%), spondylodiscitis in 21 (27.6%), enthesitis in 13 (17.1%), hip lesions in 16 (21%) and ankylosis in 10 (13.1%). Conclusions: This selective sequence imaging of the pelvis and spine was able to identify typical lesions of SpA in a shorter time period. Fifty-five percent patients had lesions in the posterior elements including facet joints and costovertbral joints that would be missed on traditional SI joint imaging.

Standalone cage versus anchored cage for anterior cervical discectomy and fusion: a comparative analysis of clinical and radiological outcomes.

PURPOSE: The use of standalone cages (SAC) and anchored cages (AC) in anterior cervical discectomy and fusion surgery (ACDF) has shown advantage of reduced operative time and lower incidence of dysphagia. However, there is limited literature available comparing the clinical and radiological outcomes of SAC and AC. METHODS: We conducted a prospective study for patients undergoing ACDF for cervical radiculopathy or myelopathy. Patient were classified based on the cage used into SAC group and the AC group. Clinical outcomes were assessed using the modified Japanese Orthopedic Association (mJOA) for myelopathy and Neck Disability Index (NDI) and Visual Analogue Scale (VAS) for radiculopathy. Dysphagia was graded as per Bazaz score. Radiologically, global cervical lordosis, segmental lordosis, cage subsidence, and migration were assessed. RESULTS: We analyzed 31 patients in each group with a minimum two year follow-up. The mean VAS improved from 7.9 to 4.56, mean NDI score improved from 27.6 to 19.8, and mean mJOA improved from 10.8 to 11.7 which were statistically significant (p < 0.05); however, no significant difference was noted between the SAC and AC groups. Mean global lordosis improved from 14.4 to 20.3° and mean segmental lordosis improved from 6 to 10.1° at six months and plateaued to 6.9° at final follow up without any significant difference between the groups. The subsidence was statistically more in 12.9% (4/31) in SAC than 6.4% (2/31) in AC. CONCLUSION: AC showed of lower rates of subsidence while both SAC and AC had comparable clinical outcomes and radiological alignment outcomes.

Osteosclerotic Multiple Myeloma without POEMS Syndrome - A Rare Case Report.

Introduction: Multiple myeloma is a plasma cell neoplasm that is commonly associated with lytic bone lesions; however, osteosclerotic multiple myeloma is a rare entity. Osteosclerotic multiple myeloma has been reported in association with POEMS syndrome. Case Presentation: A 60-year-old female patient presented to us with low back pain for 2 months. The investigations revealed that the patient had multiple osteosclerotic lesions in the axial skeleton with a L4 ivory vertebra. The serum immunoelectrophoresis was negative. Positron emission tomography scan was done which showed multiple skeletal lesions in the right iliac bone, left femoral neck, thoracic vertebrae T1, T6, T12, and lumbar vertebra L4. Biopsy and immunohistochemistry of the lesion showed plasma cell proliferation; producing lambda light chains. However, there were no features of POEMS syndrome including polyneuropathy, organomegaly, endocrinopathy, and skin changes. The patient was started on chemoradiation and achieved clinical remission and was asymptomatic at 12 months follow-up. Conclusion: Osteosclerotic myeloma without the features of POEMS syndrome is an extremely rare entity. This case reports documents a unique clinical scenario of osteosclerotic non-secretory light chain myeloma without POEMS syndrome.

Gene Xpert/MTB RIF assay for spinal tuberculosis- sensitivity, specificity and clinical utility.

BACKGROUND: Xpert MTB/RIF assay is a rapid automated molecular test with excellent reported sensitivity, specificity for diagnosis of pulmonary and extrapulmonary Mycobacterium tuberculosis (MTB) infections. However, the clinical utility and accuracy in STB is not well established. A study was conducted to report on the sensitivity, specificity and clinical utility of the Xpert MTB/RIF assay in spinal tuberculosis (STB). METHODS: A retrospective review of medical records was performed for 136 patients that underwent spinal biopsy for suspected spondylodiscitis. Reports for acid fast bacilli (AFB) smear, gram stain, pyogenic culture, MTB culture, histopathology, Xpert MTB/RIF assay, and drug sensitivity testing were reviewed. 'Reference standard for diagnosis of STB' was based on positive histopathology and/or MTB culture evidence and was considered as MTB positive. Any samples returning a positive pyogenic or fungal culture were considered as MTB negative. The sensitivity, specificity for Xpert MTB/RIF was assessed against the reference standard. RESULTS: A total of 125 patients were considered for final analysis, 86 patients met the criteria for 'Reference standard for diagnosis of TB spine' (MTB positive). This includes nine patients that were MGIT culture only positive; 45 that were histopathology only positive and 32 were both culture and histopathology positive. There were 39 culture proven (pyogenic-37 and fungal-2) patients included in MTB negative group. The 86 MTB positive patients, included 53 (61.6%) tissue samples and 33 (38.4%) pus samples. The overall analysis showed a 65.1% sensitivity, 100% specificity, 100% PPV and 56.5% NPV for the Xpert MTB/RIF. CONCLUSIONS: Gene Xpert MTB/RIF showed excellent specificity and was accurate in the identification of drug resistance. The sensitivity was 65% and sampling techniques using pus samples rather than tissue samples could be a possible reason for lower sensitivity.

Impact of Patient Counseling and Socioeconomic Factors on Initiation of Rehabilitation Program in Spinal Cord Injury Patients Presenting to a Tertiary Spine Unit in India.

STUDY DESIGN: Prospective case series. PURPOSE: This study aimed to investigate the impact of education, financial income, occupation, and patient counseling on the timing of enrolment in a spinal cord injury (SCI) rehabilitation program. OVERVIEW OF LITERATURE: A rehabilitation program following SCI is essential to improve functional outcomes. Socioeconomic factors can affect the timing of enrolment to a rehabilitation program. Literature on the effects of socioeconomic factors among patients with SCI in the Indian scenario is limited. METHODS: A prospective, consecutive analysis of patients with SCI was performed with 1-year follow-up. Assessment of the timing of enrolment to a rehabilitation program was performed using the modified Kuppuswamy socioeconomic scores (MKSS). Patients admitted to the SCI unit (group A), underwent intensive individual, group, and family counseling sessions to encourage early enrolment into a rehabilitation program. Patients presenting directly for rehabilitation (group B) were analyzed for comparison. RESULTS: A total of 153 patients were recruited. Group A was composed of 122 patients who started the rehabilitation program after a mean of 28 days, compared with a mean of 149 days for 31 patients in group B. In group A, 104 patients (85%; mean MKSS, 14.02) and 18 patients (15%; mean MKSS, 15.61) enrolled for rehabilitation <6 weeks and ≥6 weeks, respectively. In group B, 12 patients (39%; mean MKSS, 13.69) and 19 patients (61%; mean MKSS, 12.10) enrolled for rehabilitation <6 weeks and ≥6 weeks, respectively. The total MKSS and scores for education, income, and occupation did not show a significant difference between the two both groups (p>0.05). CONCLUSIONS: Early patient counseling in the acute care unit helps in the early enrolment of patients with poor socioeconomic demographic profile to a rehabilitation program.

Short-term results of a novel management of supracondylar fracture with coexisting osteoarthritis with bifold fixation and total knee arthroplasty.

PURPOSE: Presence of supracondylar and periarticular femoral fracture with associated arthritis of knee poses a challenging situation to the orthopaedic surgeon. The results of fixation of fracture in osteoporosis are not very satisfactory and have complications. With fixation alone, they still cannot bear weight on affected leg due to severe disability of osteoarthritis. To make patient walk, conventionally three surgeries in the form of fracture fixation, removal of implant and total knee arthroplasty (TKA) needs to be done in staged manner. We propose a novel management in form of bifold fixation and simultaneous TKA. METHODS: Eight cases (6 females, 2 males) of supracondylar femoral fractures with severe osteoarthritis of the knee and osteoporosis were primarily fixed with bifold fixation using SIGN nail ( www.signfracturecare.org ) and locking plate together with simultaneous total knee arthroplasty. There were five cases (2 males and 3 females) of grade 4 (Kellgren-Lawrence grading) osteoarthritis (OA) and three cases (all females) of severe rheumatoid arthritis (RA). RESULTS: The mean age was 68 years and average time for full weight bearing was 6 days. Radiographic evidence of fracture union was achieved in 16.25 weeks. The mean Knee Society Score (KSS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score at 26 months was 83.13 and 22.13 respectively. CONCLUSIONS: Single stage combined bifold osteosynthesis with interlocking nail and locking plate together with total knee arthroplasty helps in one time management of these difficult injuries. It is a cost-effective and economically sound option and gives excellent results with good patient satisfaction.

Clinical and radiological factors associated with postoperative shoulder imbalance and correlation with patient-reported outcomes following scoliosis surgery.

BACKGROUND: Shoulder balance (SB) is an important cosmetic concern and is a determinant to assess outcomes following scoliosis surgery. Shoulder imbalance (SI) has been studied predominantly in idiopathic scoliosis with limited literature on other etiologies. PURPOSE: To assess SB following scoliosis surgery and correlate SRS-30 self-image scores with radiological shoulder imbalance SI. METHODS: A retrospective analysis was performed for 43 patients undergoing scoliosis surgery with a minimum 2-year follow-up. Radiological SI was assessed by the coracoid height difference on whole spine standing radiographs at preoperative, 12-weeks postoperative and 2-year follow-up. The preoperative Cobb angle, postoperative Cobb angle and mean correction were recorded. The upper and lower end vertebrae (UEV/LEV), and instrumented vertebrae (UIV/LIV) were documented. The aetiology of scoliosis and functional outcomes based on the SRS-30 questionnaire were noted. RESULTS: There were 19 males and 24 females with a mean age of 14.5 ± 4.7 years. The 12-week postoperative radiographs showed SI in 15 patients and residual SI in 7 patients at 2-year follow-up. SI was seen in four congenital scoliosis with segmentation or mixed anomalies in the proximal thoracic spine. Two idiopathic scoliosis (Lenke type 1 and type 3) showed SI where the UIV was T3 and T2 respectively. The mean preoperative SRS-30 score for patients with SB (N = 9) was 2.5 ± 0.72 and for SI (N = 34) was 3 ± 0.42 without significant difference (p > 0.5). The final mean SRS-30 self-image score for patients with SB was 3.7 ± 0.54 and for patients with SI was 3.7 ± 0.53 without significant difference (p > 0.05). CONCLUSION: Radiological SI assessed by coracoid height difference was not associated with a significant difference in SRS 30 scores preoperatively and at 2 year follow up. SI was seen with congenital scoliosis associated with segmentation and mixed anomalies of the proximal thoracic spine.

Assessment of Interobserver Variability for CT Scan-Based Evaluation of Posterior Ligament Complex Injury in Thoracolumbar Fractures: An International Multicenter Pilot Study.

STUDY DESIGN: A multicenter, pilot study, for radiological assessment of thoracolumbar spine fractures was performed with the participation of 7 centers in Africa, Europe, Asia, and South America as a part of the AO Foundation network. OBJECTIVES: To determine the interobserver variability for computed tomography (CT) scan-based evaluation of posterior ligament complex (PLC) injury in thoracolumbar fractures. METHODS: Forty-two observers including 1 principal investigator at each participating center performed variability assessment. Each center contributed toward a total of 91 patient images with A3 or A4 thoracolumbar burst fractures (T11-L2) with or without suspected PLC injury. Pathological fractures, multilevel injuries, obvious posterior bony element injury and translation/dislocation injuries were excluded. Ten patients were randomly selected and commonly reported CT parameters indicating PLC injury, including superior inferior endplate angle, vertebral body height loss, local kyphotic deformity, interspinous distance and interpedicular distance were assessed for variability. Observer values were compared with an experienced gold rater in spinal trauma. Analysis of variability was performed for all observers, between the principal investigators and also between observers participating in each center. RESULTS: The studied parameters showed considerable variability in measurements among all observers and amongst all participating centers. The variability between the principal investigators was lower, but still substantial. The deviation of observer measurements from the gold rater were also significant for all CT parameters. CONCLUSIONS: CT-based radiological parameters previously reported to be suggestive of PLC injury showed considerable variability and magnetic resonance imaging verification of a PLC injury in all doubtful cases is suggested.

Aneurysmal bone cyst of C2 treated with novel anterior reconstruction and stabilization.

PURPOSE: Aneurysmal bone cysts (ABC) form 1 % of primary bone tumors. Reported incidence rates are no more than 1.4 to 1,00,000. ABC of spine frequently involves posterior elements and commonly affects the lumbar spine (45 %). We present a case of C2 ABC for the challenges it poses due to the rarity of the lesion, tedious to access location, dilemmas relating to the suitable approach for tumor resection and technically demanding stabilization and reconstruction strategy post resection. METHODS: Clinical data analysis was performed to discuss a method of novel anterior column reconstruction following resection of a C2 aneurysmal bone cyst in a 8 year old child with anterior and posterior elements being involved. RESULTS: An 8-year-old girl with an aneurysmal bone cyst of the C2 vertebra underwent staged surgery following pre-operative embolisation. First a posterior approach tumor excision with posterior instrumented fusion was performed. Following which, using a modified anterior retropharyngeal approach anterior tumor excision and fibular graft reconstruction between the C1 lateral mass and C2 body was performed. Complete tumor clearance and stable reconstruction was successfully achieved in our patient. Patient showed excellent clinical outcome with radiological fusion. CONCLUSIONS: Preoperative embolisation in the treatment of ABC has supplemental advantage by reducing blood loss. Modified anterior retropharyngeal approach allows satisfactory clearance for C1-2 lesion and fibular strut graft between the C1 lateral mass and C2 body can provide a stable graft placement with good chance of fusion. Instability and spinal deformity, whether preexisting or post-excision, should be corrected with reconstruction and stabilization to offer best chance of cure in such cases.

Factors Affecting Early and 1-Year Motor Recovery Following Lumbar Microdiscectomy in Patients with Lumbar Disc Herniation: A Prospective Cohort Review.

STUDY DESIGN: Prospective cohort study. PURPOSE: The study was aimed at evaluating clinicoradiological factors affecting recovery of neurological deficits in cases of lumbar disc herniation (LDH) treated by lumbar microdiscectomy. OVERVIEW OF LITERATURE: The majority of the available literature on neurological recovery following neurodeficit is limited to retrospective series. The literature is currently limited regarding variables that can help predict the recovery of neurodeficits following LDH. METHODS: A prospective analysis was performed on 70 consecutive patients who underwent lumbar microdiscectomy (L1-2 to L5-S1) owing to neurological deficits due to LDH. Patients with motor power ≤3/5 in L2-S1 myotomes were considered for analysis. Follow-up was performed at 2, 6, and 12 months to note recovery of motor deficits. Clinicoradiological parameters were compared between the recovered and nonrecovered groups. RESULTS: A total of 65 patients were available at the final follow-up: 41 (63%) had completely recovered by 2 months; four showed delayed recovery at the 6-month follow-up; and 20 (30.7%) showed no recovery at 1 year. Clinicoradiological factors, including diabetes, complete initial deficit, areflexia, multilevel disc prolapse, longer duration since initial symptoms, and ≥2 previous symptomatic episodes were associated with a significant risk of poorer recovery (p<0.05 for all). Age, sex, occupation, smoking, level/type or location of disc herniation, primary canal stenosis, disc fragment dimensions, precipitating factors, bladder involvement, bilaterality of symptoms, and the presence or absence of anal reflex did not affect neurological recovery (p>0.05 for all). Diabetes mellitus (p=0.033) and complete initial motor deficit (p=0.028) were significantly associated with delayed recovery in the multivariate analysis. CONCLUSIONS: The overall neurological recovery rate in our study was 69%. Diabetes mellitus (p=0.033) and complete initial motor deficit were associated with delayed motor recovery.

Factors Influencing Postoperative Urinary Retention Following Elective Posterior Lumbar Spine Surgery: A Prospective Study.

STUDY DESIGN: Prospective observational study. PURPOSE: To determine the incidence of postoperative urinary retention (POUR) in patients undergoing elective posterior lumbar spine surgery and identify the risk factors associated with the development of POUR. OVERVIEW OF LITERATURE: POUR following surgery can lead to detrusor dysfunction, urinary tract infections, prolonged hospital stay, and a higher treatment cost; however, the risk factors for POUR in spine surgery remain unclear. METHODS: A prospective, consecutive analysis was conducted on patients undergoing elective posterior lumbar surgery in the form of lumbar discectomy, lumbar decompression, and single-level lumbar fusions during a 6-month period. Patients with spine trauma, preoperative neurological deficit, previous urinary disturbance/symptoms, multiple-level fusion, and preoperative catheterization were excluded from the study. Potential patient- and surgery-dependent risk factors for the development of POUR were assessed. Univariate analysis and a multiple logistical regression analysis were performed. RESULTS: A total of 687 patients underwent posterior lumbar spine surgery during the study period; among these, 370 patients were included in the final analysis. Sixty-one patients developed POUR, with an incidence of 16.48%. Significant risk factors for POUR were older age, higher body mass index (BMI), surgery duration, intraoperative fluid administration, lumbar fusion versus discectomy/ decompression, and higher postoperative pain scores (p<0.05 for all). Sex, diabetes, and the type of inhalational agent used during anesthesia were not significantly associated with POUR. Multiple logistical regression analysis, including age, BMI, surgery duration, intraoperative fluid administration, fusion surgery, and postoperative pain scores demonstrated a predictive value of 92% for the study population and 97% for the POUR group. CONCLUSIONS: POUR was associated with older age, higher BMI, longer surgery duration, a larger volume of intraoperative fluid administration, and higher postoperative pain scores. The contribution of postoperative pain scores in the multiple regression analysis was a significant predictor of POUR.

Coronal Vertebral Dislocation Due to Congenital Absence of Multiple Thoracic and Lumbar Pedicles: Report of Three Cases, Review of Literature, and Role of Intraoperative CT Navigation.

STUDY DESIGN: Case report OBJECTIVE: To present three cases of coronal vertebral dislocation due to congenital multiple thoracic and lumbar pedicle agenesis. SUMMARY OF BACKGROUND DATA: Congenital pedicle agenesis is an uncommon condition and is frequently identified as an incidental finding on diagnostic imaging in asymptomatic individuals. This agenesis is frequently limited to a single level and is commonly seen in the cervical and lumbar spine. METHODS: We report three patients who presented with multiple thoracic and lumbar pedicle agenesis resulting in coronal vertebral dislocation. The patients presented with progressive kyphoscoliosis deformity. Identification of this malformation on conventional radiographs is difficult, and computed tomographic (CT) scan with 3D reconstruction provides a better delineation of the deformity. RESULTS: Computed tomography showed complete absence of pedicles and dissociation of anterior column from the posterior column, resulting in coronal vertebral dislocation. Magnetic resonance imaging confirmed the absence of pedicles and decreased anteroposterior diameter, causing canal stenosis. Two patients were treated by spanning internal fixation, partial deformity correction, and posterior fusion, with satisfactory results. CONCLUSION: Coronal vertebral dislocation can be easily missed on plain radiograph because many patients with severe scoliotic deformity have thin or sclerotic pedicles. Computed tomography is essential to demonstrate these anomalies. It is important to recognize pedicle aplasia early to prevent rapid progression of deformity and neurologic deficit.

A Classification for Kyphosis Based on Column Deficiency, Curve Magnitude, and Osteotomy Requirement.

BACKGROUND: There is a lack of a classification system providing uniformity in description and guiding management decisions for kyphotic spinal deformities. We developed such a classification based on column deficiency, flexibility of disc spaces, curve magnitude, and correlation with the corrective osteotomy required. METHODS: A classification was developed based on analysis of 180 patients with thoracolumbar kyphosis requiring osteotomy. The deformity was classified as Type I if the anterior and posterior columns were intact (IA indicated mobile disc spaces and IB, ankylosed segments). Type II indicated deficiency of only 1 column (IIA = anterior column and IIB = posterior column). Type III indicated deficiency of both columns (IIIA = kyphosis of ≤60°, IIIB = kyphosis of >60°, and IIIC = buckling collapse). A prospective analysis of 76 patients was performed to determine interobserver variability and the ability of the classification to guide selection of osteotomies of increasing complexity, including the Ponte osteotomy, pedicle subtraction osteotomy, disc bone osteotomy, single vertebrectomy, multiple vertebrectomies, and anterior in situ strut fusion procedure. RESULTS: The mean age of the 76 patients was 21.2 years, the mean kyphosis was 69.9° (range, 26° to 120°), and the mean follow-up duration was 30 months. Six deformities were classified as IA, 5 as IB, 5 as IIA, 2 as IIB, 13 as IIIA, 35 as IIIB, and 10 as IIIC. Four surgeons classifying the deformities had a high agreement rate (kappa = 0.83), with the highest agreement for Types IA, IB, and IIIB. A correlation between the type of deformity and the osteotomy performed demonstrated that the classification could indicate the type of osteotomy required. All 18 patients with Type-I or II kyphosis were treated with Ponte, pedicle subtraction, or disc bone osteotomy. Forty-three (90%) of the 48 patients with Type IIIA or IIIB underwent vertebrectomy (single in 27 [56%] and multiple in 16 [33%]), and only 5 (10%) underwent disc bone osteotomy. Seven of the 10 patients with Type-IIIC kyphosis were treated with multiple vertebrectomies, with 5 of them needing preoperative halo gravity traction; the other 3 patients underwent an anterior in situ strut fusion procedure. CONCLUSIONS: The proposed classification based on the morphology of column deficiency, flexibility, and curve magnitude demonstrated a high interobserver agreement and ability to guide selection of the appropriate osteotomy. CLINICAL RELEVANCE: A novel classification system for kyphosis based on spinal column deficiency, flexibility of disc spaces, and curve magnitude would bring uniformity in management and help guide surgeons in the choice of the appropriate corrective osteotomy.

Reciprocal Changes in Sagittal Alignment in Adolescent Idiopathic Scoliosis Patients Following Strategic Pedicle Screw Fixation.

STUDY DESIGN: Retrospective observational study. PURPOSE: To analyze the effect of low-density (LD) strategic pedicle screw fixation on the correction of coronal and sagittal parameters in adolescent idiopathic scoliosis (AIS) patients. OVERVIEW OF LITERATURE: LD screw fixation achieves favorable coronal correction, but its effect on sagittal parameters is not well established. AIS is often associated with decreased thoracic kyphosis (TK), and the use of multi-level pedicle screws may result in further flattening of the sagittal profile. METHODS: A retrospective analysis was performed on 92 patients with AIS to compare coronal and sagittal parameters preoperatively and at 2-year follow-up. All patients underwent posterior correction via LD strategic pedicle screw fixation. Radiographs were analyzed for primary Cobb angle (PCA), coronal imbalance, cervical sagittal angle (CSA), TK, lumbar lordosis (LL), pelvic incidence, pelvic tilt (PT), sacral slope (SS), C7 plumb line, spino-sacral angle, curve flexibility, and screw density. RESULTS: PCA changed significantly from 57.6°±13.9° to 19°±8.4° (p <0.0001) with 67% correction, where the mean curve flexibility was 41% and screw density was 68%. Regional sagittal parameters did not change significantly, including CSA (from 10.76° to 10.56°, p =0.893), TK (from 24.4° to 22.8°, p =0.145), and LL (from 50.3° to 51.1°, p =0.415). However, subgroup analysis of the hypokyphosis group (<10°) and the hyperkyphosis group (>40°) showed significant correction of TK (p <0.0001 in both). Sacro-pelvic parameters showed a significant decrease of PT and increase of SS, suggesting a reduction in pelvic retroversion SS (from 37° to 40°, p =0.0001) and PT (from 15° to 14°, p =0.025). CONCLUSIONS: LD strategic pedicle screw fixation provides favorable coronal correction and improves overall sagittal sacro-pelvic parameters. This technique does not cause significant flattening of TK and results in a favorable restoration of TK in patients with hypokyphosis or hyperkyphosis.