Posterior Deformity Research Articles

Frontal Mucocoeles: The Frontal Pick

Objective: Treatment of frontal mucocoeles through an endoscopic approach is a cornerstone of minimally invasive surgery. However lysis of the posterior wall of the frontal sinus may provide significant morbidity. The focus of this study is to propose an algorithm to select mucocele drainage versus sinus obliteration. Method: Retrospective review based on 37 cases of frontal mucocoeles with erosion of the posterior wall treated from 2000 to 2009. Results: While most of the cases with extensive posterior wall lysis have been successfully addressed through minimal invasive treatment, two patients presented with a “frontal pick” (ie, localized posterior wall deformity). The first patient underwent intractable CSF rhinorrhea 3 months after endoscopic marsupialization of the cyst. A “frontal pick” could be visualized, which had torn open the dura due to the relief of mucocele counterpressure. A subfrontal approach allowed obliteration of the sinus and performance of a duraplasty. The second patient was identified and successfully approached subfrontally, which allowed dissection of the frontal pick. Conclusion: When posterior wall of the frontal sinus results in a sharp-angled deformity of the posterior wall, then endoscopic marsupialization may result in CSF rhinorrhea due to tearing of the dura after relieving the counter pressure exerted by the mucocele. A sinus obliteration should then be performed.

Vectored Cranial-Cervical Traction Limits Facial Contact Pressure from Prone Positioning During Posterior Spinal Deformity Surgery

Prospective, two-way complete block design analyzing facial contact pressures during prone positioning with the use of cervical traction for spinal surgery. Level 2 evidence. To assess the effect of varying traction angle and traction weight to limit facial contact pressure. Posterior spine surgery has known hazards related to the prone positioning. Cervical traction is used to limit downward pressure exerted to the face to stabilize the head and neck and to aide in deformity correction. The effects of the traction angle and force on facial contact pressure have not been studied. Facial contact pressure was measured for 10 patients undergoing posterior spine surgery in the prone position with Gardner-Wells tongs applied for cervical traction. The facial contact pressure was measured with a force transducer at each of three angles from horizontal (0°, 30°, 45°) and each of four traction weights (0, 5, 10,15 lb), a total of 12 measurement parameters for each patient. An in-line tensiometer provided consistent application of force throughout the traction system. Ten patients, average age 15 ± 0.6 years, six female, BMI 21.3 ± 1.7, underwent facial pressure monitoring. Post hoc analysis showed that both higher traction weights and angles significantly limited facial pressure (P = 0.0001). The lowest overall average facial pressure of 0.51 lb (95% CI = 0.28-0.73) occurred with 15 lb of traction applied at 45° above the horizontal. This was significantly less facial pressure than found when traction was applied at all weights tested using the commonly employed 0° in-line traction angle (P < 0.0001). A combination of upward vectored 45° traction angle and 15 lb of weight significantly decreased facial contact pressure. The use of an "in-line tensiometer" assured an accurate force application.

Surgical Treatment of Kyphosis in Children in Healed Stages of Spinal Tuberculosis

Very less literature focuses on the treatment of kyphosis in healed stages of spinal tuberculosis (TB), especially in children. The purpose of this study was to evaluate the outcomes of anterior release, decompression, deformity correction, and instrumented fusion, followed by posterior osteotomy, deformity correction, and pedicle screw instrumented fusion, which is used to treat kyphosis in children in healed stages of spinal TB. Sixteen children with kyphotic deformity of the spine in healed stages of TB underwent anterior release, decompression, deformity correction, and instrumented fusion, followed by posterior osteotomy, deformity correction, and pedicle screw instrumented fusion between 2003 and 2007 with at least 2 years of follow-up. Radiologic assessment including the angle of kyphosis and scoliosis, and neurologic status using the modified Frankel grade were analyzed before surgery, after surgery, and at the last follow-up. Fusion was evaluated on flexion-extension lateral radiographs. Good cosmetic results were achieved in all patients. Neurologic improvement was shown in all 4 patients with paraplegia. The mean preoperative angle of kyphosis was 55.8 degrees that reduced to 21.7 degrees, postoperatively. The difference in the mean angle of kyphosis was statistically significant (P<0.05). The mean angle of kyphosis at the last follow-up was 23.2 degrees. The mean correction loss was 1.5 degree, and there was no statistically significant difference in the mean angles of kyphosis between the postoperative and last follow-up measurements. The mean preoperative angle of scoliosis was 6.9 degrees that reduced to 0.8 degree postoperatively. The difference in the mean angle of scoliosis was statistically significant (P<0.05). The mean angle of scoliosis at the last follow-up was 0.9 degree. The mean correction loss was 0.2 degree and there was no statistically significant difference in the mean angles of scoliosis between the postoperative and last follow-up measurements. All patients returning for follow-up had bony fusion. There were no cases of failure of fixation. Combined anterior and posterior osteotomy, deformity correction, and instrumented fusion halted progression of kyphosis and improved neurologic symptoms. Therapeutic-level IV, retrospective study.

Bandverletzungen des Kniegelenkes

Due to their infrequency, injuries to the PCL are often overlooked. In addition to clinical examination, posterior stress X-rays are crucial in the diagnostic algorithm. The stress X-rays can also provide insight into the frequently associated posterolateral instabilities and the phenomenon of fixed posterior drawers. In severe posterior instabilities an arthroscopic PCL reconstruction using an autologous semitendinosus-gracilis graft is performed. In cases with associated posterolateral instabilities, we perform a posterolateral reconstruction using a modified Larson technique in the same setting. In chronic posterior instabilities and varus deformity, a high tibial osteotomy is performed. Posterior instabilities require specific diagnostic pathways, indications and surgical techniques. Therefore, this instability should only be treated by experienced surgeons at specialized centers.

Bone Morphogenetic Protein (RhBMP-2) as a Substitute for Iliac Crest Bone Graft in Multilevel Adult Spinal Deformity Surgery

Prospective, single center, nonblinded radiographic analysis of anterior and posterior adult spinal deformity fusions performed with bone morphogenetic protein (rhBMP-2). To determine the ability of rhBMP-2 to achieve multilevel spinal fusion in the deformity patient. No previous study has evaluated rhBMP-2 for multilevel adult spinal deformity fusion with 2-year results. We postulated fusion could be achieved without distant autogenous graft harvest. Prospective analysis was performed for 98 patients (308 levels; mean age, 51.4 years) who underwent multilevel anterior or posterior spinal fusion (PSF) with minimum 2-year follow-up (average, 2.6 years). Group 1 (10 mg/level) contained 47 patients (109 levels; 2.33 levels/patient) who underwent anterior spinal fusion (ASF): BMP on an absorbable collagen sponge (ACS) with a titanium mesh cage. Group 2 (20 mg/level) included 43 patients (156 levels; 3.63 levels/patient) with PSF: BMP on an ACS with local bone graft (LBG) and bulking agent [tricalcium phosphate/hydroxyapatite (TCP-HA)]. Group 3 (40 mg/level) contained 8 patients (43 levels; 5.38 levels/patient) with PSF: rhBMP-2 and TCP-HA with no autologous bone. Confounding negative factors were present in the study population: medical comorbidities (26%), tobacco use (17%), revision surgery (34%), previous laminectomy (51%), and preoperative pseudarthrosis (27%). Postoperative films (AP, lateral, oblique) were evaluated by independent observers. Average fusion grade was based on a published scale. Overall fusion rate was 95%. (group 1 91%, group 2 97%, group 3 100%). No confounding factor demonstrated a detrimental statistical significance to fusion. In multilevel ASF, BMP (10 mg/level) generates fusion without autogenous bone. In multilevel PSF, BMP (20 mg/level) with LBG and TCP-HA produced fusion. BMP (40 mg/level) and TCP-HA without LBG achieved fusion. In multilevel spinal fusion, rhBMP-2 eliminated the necessity for iliac crest bone graft and yielded an excellent fusion rate.

MINIMALLY INVASIVE POSTERIOR FIXATION

Significant advances have been made in the contemporary management of thoracolumbar spinal deformities, including improved segmental bony fixation, techniques for osteotomy, and mechanically powerful reduction maneuvers, which now allow the spinal surgeon to correct severe, complex, and rigid spinal deformities. However, one of the major limitations of surgical intervention has been the high complication rates associated with these surgical endeavors. Much of the morbidity associated with posterior deformity surgery relates to the extensive soft tissue destruction necessary to gain access to multiple segments of the axial skeleton. The open exposures for long-segment fixation result in additional blood loss, increased rates of infection, and prolonged immobilization caused by postoperative pain. Minimally invasive techniques attempt to overcome these drawbacks of the open exposures, and this report reviews preliminary experience in treating spinal deformities with long-segment minimally invasive internal fixation.

Controlled Cervical Extension Osteotomy for Ankylosing Spondylitis Utilizing the Jackson Operating Table

Technical note. To demonstrate a controlled extension osteotomy technique of the cervical spine in a prone position and using the head elevator mechanism on the Jackson operating table to correct a chin-on-chest deformity in a patient with ankylosing spondylitis. Catastrophic cord injury causing quadriplegia and death has been associated with correction of chin-on-chest deformity in patients with ankylosing spondylitis. Manual control of spinal column motion during and after osteoclasis or osteotomy can be difficult, inexact, and anxiety inducing. A 45-year-old woman with ankylosing spondylitis and severe chin-on-chest deformity underwent a posterior C7 pedicle subtraction osteotomy, deformity correction, and instrumented fusion in a prone position on the Jackson operating table. By using the elevator mechanism attached to the head of the operating table and Mayfield tongs, the patient's cervicothoracic junction was placed into extension by over 30 degrees in controlled increments. We present a technique for controlled extension osteotomy correction of chin-on-chest deformity in a prone position. Use of the operating table mechanism in conjunction with a closing-wedge osteotomy diminishes the risk of translation, decreases risk of air embolus associated with a sitting position, and promotes greater opportunity for fusion through the osteotomy, and the stability allows for placement of modern instrumentation.

Treatment of Severe, Painful Pes Planovalgus Deformity with Hindfoot Arthrodesis and Wedge-Shaped Tricortical Allograft

This study tested the hypothesis that modification of the standard technique of hindfoot arthrodesis with the use of a wedge-shaped tricortical allograft would improve the amount of correction of pes planovalgus deformity. The results were compared to previous reports. Between 1998 and 2005, the senior author (LBC) performed 13 hindfoot arthrodeses on 12 patients using an allograft to improve correction of the deformity for severe, painful pes planovalgus deformity. The average patient age was 55 (range 27 to 77) years. There were seven women and five men. The indications were posterior tibial tendon dysfunction (seven feet), rheumatoid arthritis (three feet), post-traumatic arthritis and deformity (one foot), congenital pes planovalgus (one foot), and tarsal coalition (one foot). Twelve of 13 feet achieved union by 12 weeks postoperatively. There was one nonunion. The average time to fusion was 12 weeks. All 12 patients were satisfied with the results of the operation. The average postoperative American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score was 87 points, and the AOFAS Midfoot score was 85 points. Preoperative and postoperative radiographs were compared to evaluate correction of deformity. On lateral weightbearing views, the talo-first metatarsal angle improved from 15 to 6 degrees, and the lateral talocalcaneal angle improved from 48 to 35 degrees. On anteroposterior views, the talo-first metatarsal angle improved from 17 to 7 degrees, the talonavicular coverage decreased from 28 to 13 degrees, and the talocalcaneal angle improved from 23 to 13 degrees. A simple modification of the addition of allograft to a common procedure of hindfoot arthrodesis to treat severe, painful pes planovalgus results is reliable and offers satisfactory correction.

Remodeling of Tibial Fractures in Children Younger Than 12 Years

Forty-eight children with an average age of 7.2 years (range: 3-12 years) were examined clinically and radiographically at an average 4-year follow-up (range: 2-10 years), between 1989 and 2000 to analyze correction of deformities following tibial shaft fractures. An inconsistent alteration in the length of the fractured tibia was observed. Anterior angular deformity realigned maximally (52.7%) followed by varus (40.9%) and valgus (23.9%) deformities. Posterior deformity corrected the least (18.5%). In the sagittal plane, acceptable critical anterior and posterior angular deformities that corrected completely were 12 degrees and 6 degrees respectively. In the coronal plane, acceptable critical angular deformities were 10 degrees varus and 8 degrees valgus.

Bimaxillary Osteotomy in a Female Patient with Hemophilia A

We report here a case of a 22-year-old female patient with hemophilia A who had a bimaxillary osteotomy operation. Adequate replacement of Factor VIII and DDAVP(1 deamino-8-D-arginine vasopressin) led to the achievement of hemostasis during and after the surgery. Le Fort I maxillary osteotomy and mandibular sagittal split osteotomies were done to correct the facial profile of this hemophiliac patient with a class III malocclusion and posterior open-bite deformity. Careful preoperative evaluation and close cooperation with the hematologist are required if surgery is to be successful. The operation was uneventful and no postoperative complication was observed.

Chiari malformation in craniosynostosis

Chiari malformation (CM) is a frequent finding in multisutural and syndromic craniosynostosis, occurring in 70% of patients with Crouzon's syndrome, 75% with oxycephaly, 50% with Pfeiffer's syndrome and 100% with the Kleeblattschädel deformity. The pathogenesis of this condition and rationale for treatment are still controversial. Since its first description in 1972, several factors have been cited to play a role in inducing CM. In the light of recent publications, the roles of premature fusion of cranial vault and cranial base sutures, of congenital anomalies of the cerebellum and brain stem, of raised intracranial pressure, of venous hypertension and of hydrocephalus are reviewed. Evaluation and management of CM are also discussed. Chiari malformation appears to be an acquired and progressive condition that develops in the first months of life, because of a disproportion between hindbrain growth and an abnormally small posterior fossa, a consequence of the premature fusion of lambdoid and cranial base sutures. Venous hypertension caused by stenosis of the jugular foramen can also be present in these patients, resulting in intracranial hypertension and/or hydrocephalus. Careful MRI evaluation is recommended for the forms of craniosynostosis at a high risk of developing hindbrain herniation. The selection of posterior cranial vault expansion as the first surgical procedure is advocated. In selected cases, treatment of the posterior cranial deformity by occipital vault remodelling and treatment of the Chiari-like deformity by suboccipital decompression can be carried out using the same surgical procedure.

Ganglioneuroma masquerading as spinal pain

Objective: To discuss the clinical features of ganglioneuroma and to propose it as a differential diagnosis for a young patient suffering from chronic back pain. Clinical Features: A 25-year-old patient suffered from chronic mid-thoracic pain and a history of scoliosis. The physical examination result was unremarkable; thus radiographs were obtained. A posteroanteriorand lateral chest radiograph demonstrated a well-defined opacity extending from the region of the left hilum to below the diaphragm. A differential diagnosis of a posterior mediastinal mass was advanced. Computed tomography revealed a homogenous, nonenhancing left posterior mediastinal mass with adjacent posterior rib deformity. Computed tomography (CT)–guided biopsy subsequently defined the mass as a ganglioneuroma. Intervention and Outcome: The mass was surgically resected. Although the patient experienced some postsurgical discomfort, she has faired well. Conclusion: Twenty percent of mediastinal tumors are neurogenic, and 10% of neurogenic tumors are ganglioneuromas. In spite of the rarity of this tumor, ganglioneuroma should be considered in the differential diagnosis of young patients suffering from back pain. The diagnosis is important to ascertain because surgical resection is curative and can relieve the symptoms.

Surgical approach to posterior skull deformity

The incidence of occipital skull flattening in infants has recently increased, partly as a result of widespread supine positioning to prevent sudden infant death syndrome. The authors discuss the causes and differential diagnosis of posterior skull deformity in this subpopulation of patients and describe their technique for surgical correction of the condition.

CHEST INJURY - LACROSSE

1492 History A 19 year old male lacrosse player sustained a chest injury while playing lacrosse. The athlete was directly hit by another player's shoulder in the mid chest and was knocked to the ground. The athlete continued to play. However, during exertion he developed increased substernal chest pain and shortness of breath. The athlete was transported to a local community Emergency Department. Physical Examination The examination in the Emergency Department revealed a well developed athlete with stable vital sings: blood pressure -110/60, heart rate - 80, respiratory rate - 20 and temperature of 984. There was swelling on the left lateral region of the neck with subcutaneous emphysema. The neck revealed a midline trachea without posterior tenderness, pain or deformity and full range of motion. The chest examination revealed palpable left supraclavicular subcutaneous emphysema, mediastinal crunch with distant breath sounds secondary to the athletes inability to fully inspire. There also was palpable pain of left chest wall inferior to the nipple. The cardiac auscultation revealed distant heart sounds and audible crunch. The athlete was placed on a cardiac monitor. An intravenous line established and oxygen applied. A chest x-ray, EKG, ABG was obtained. Pneumothorax Pulmonary Contusion Cardiac Contusion/Tamponade Pneumomediastinum Multiple Rib Fractures Chest Wall Contusion Chest X-ray - Pneumomediastinum with air tracking to neck and towards the soft tissues in the shoulder. No pneumothorax. Sternum - no fracture CXR Inspiratory and Expiratory X-rays - no pneumothorax CT Chest - Pneumomediastinum, no pneumothorax, peripheral lung mass or pleural effusion Echocardiography - normal chambers, no pericardial effusion EKG - normal sinus rhythm, nonspecific. ST-T wave changes consistent with early repolarization. Negative ectopy. ABG - ph 7.40/39/104/24/98% (Room air) Final Working Diagnosis: Pneumomediastinum Admission to hospital to Intensive Care-Thoracic Surgery Service Cardiac monitor Senal cardiac enzyme analysis Repeat chest x-rays Discharged after 3 days with normal CPK-MB & EKG's and unchanged CXR and stable vital signs. No strenuous activity for 1 month and follow-up.

Spinal level of fetal myelomeningocele: does it influence ventricular size?

Our objective was to determine whether the level of the spinal defect influences ventricular size in fetuses with myelomeningoceles. Sonograms of 51 fetuses with open spina bifida were reviewed to determine the gestational age, ventricular atrial diameter, severity of posterior fossa deformity, and the level of the spinal defect. Four categories for spinal defect level were used: sacral, low lumbar, high lumbar, and thoracic. Regression models for ventricular atrial diameter were fit, adjusting for gestational age, posterior fossa deformity, and spinal defect level. A Fisher's exact test was used to investigate a relationship between the level of the spinal defect and the severity of the posterior fossa deformity. Spinal defect level was distributed among the four categories as follows: sacral (n = 7), low lumbar (n = 30), high lumbar (n = 10), and thoracic (n = 4). The level of the spinal defect did not significantly affect ventricular size (p > .1), and the level of the spinal defect did not show any relationship to the severity of the posterior fossa deformity (p > .8). The level of the spinal defect does not independently affect the degree of ventriculomegaly or severity of the posterior fossa deformity in fetuses with myelomeningoceles.

Direct Spinal Curvature Digitization in Scoliosis Screening???A Comparative Study with Moir?? Contourgraphy

The forward bending test, widely used in scoliosis screening, is associated with high false-positive rates. We postulate that direct surface measurement of the spinal curvature by digitization of the spinous processes used in combination with the forward bending test could increase the predictive value of detecting scoliosis without sacrificing sensitivity. Sixty consecutive patients referred from a school screening program were included in this study. All had moiré contourgraphy, spinous process digitization, and erect frontal radiographs of the spine. The number of false positives from the forward bending test was 35. Moiré contourgraphy did not reduce the number of false positives significantly. A posterior spinal deformity of 10 degrees or more predicted scoliosis in all patients, with 15 false-positive readings. Direct measurement of the spinal curvature by spinous process digitization can be an effective second-stage screening tool for scoliosis in centers where all the screened positives are referred to a single center.

Occipital flattening in the infant skull.

Occipital plagiocephaly caused by lambdoid synostosis is rare. Positional flattening is more common and will most often respond to conservative measures. Surgical correction of a flat occiput is warranted if the deformity is profound. Skull molding devices may be effective for treating mild abnormalities but are ineffective in the more severe cases. An operative procedure is described that uses a microplate-reinforced median bar to provide a rigid scaffold to maintain the occipital correction. Seventy-three consecutive patients were evaluated over a 3-year period for occipital plagiocephaly. Of these individuals, only one had true lambdoid synostosis and six required surgery. There were no operative complications and cranial length was increased from 84 to 94% of age-matched controls after surgery. The need for operative intervention is rare; however, it should be based on the severity of the posterior deformity, especially when accompanied by compensatory frontal bossing, and not on the etiology of the flattening.

Prevalence of ventriculomegaly in association with myelomeningocele: correlation with gestational age and severity of posterior fossa deformity.

To investigate the relationship of ventriculomegaly (VM) with gestational age (GA) and the severity of the associated Chiari II malformation. The sonograms of 51 fetuses with myelomeningoceles were retrospectively reviewed. VM was judged to be present when the transverse ventricular atrial diameter was greater than 10 mm. The severity of the posterior fossa (PF) deformity was subjectively graded as mild, moderate, or severe. Thirty-four fetuses were scanned at < or = 24 weeks GA, and 17 were scanned at > 24 weeks GA. The prevalence of VM was 61%. However, only 44% of fetuses < or = 24 weeks GA had VM, whereas 94% of fetuses > 24 weeks GA had VM. When compared with fetuses with mild PF deformities, fetuses with moderate or severe deformities had a higher prevalence of VM and the largest ventricles. The prevalence of VM in fetuses with myelomeningoceles varies with both GA and the severity of the associated PF deformity. These observations may provide additional prognostic information once a myelomeningocele is detected at sonography.

The Clinical Application of Neurogenic Motor Evoked Potentials to Monitor Spinal Cord Function During Surgery

The purpose of this study was to report results from 300 cases (177 children, 123 adults) administered somatosensory and neurogenic motor evoked potentials during surgery. Of these 300 cases, there were 16 cases of spinal fractures, 16 neurosurgical cases, 28 vascular cases, and 240 cases of elective posterior spinal deformity requiring instrumentation. Results indicated that somatosensory evoked potentials, especially cortical components, demonstrated greater variability than neurogenic motor evoked potentials. Variability was attributed to anesthesia and unknown factors. Neurogenic motor evoked potentials proved to be a more valid indicator of postoperative motor status than somatosensory evoked potentials. Based on their anatomic substrates and results from this study, it was recommended that somatosensory evoked potentials and neurogenic motor evoked potentials be used to monitor spinal cord function during surgery that would place that structure at risk.

Cobb Angle Versus Spinous Process Angle in Adolescent Idiopathic Scoliosis The Relationship of the Anterior and Posterior Deformities

The standard clinical measurement for adolescent idiopathic scoliosis is the Cobb angle, measured from the end-plates of the end vertebral bodies in a standing radiograph. This measurement of anterior column structures describes the anterior spinal deformity. The posterior spinal deformity can be described by the "spinous process angle," measured from a curve joining the tips of the spinous processes. A computer model, and a radiographic study of Cobb angle, spinous process angle and vertebral rotation show that adolescent idiopathic scoliosis results in larger angulations of the anterior elements than posterior elements. This helps to explain some of the inherent limitations of posterior instrumentation, including Cotrel-Dubousset instrumentation, and of noninvasive posterior surface measurement systems.