Does improved radiographic alignment truly enhance dynamic functional balance?

Prospective, concurrent-cohort study. To establish the relationship between radiographic alignment parameters and functional CoE measurements at one week before and at three months after realignment surgery in ADS patients. Adult degenerative scoliosis (ADS) represents a significant healthcare burden with exceedingly high and increasing prevalence, particularly among the elderly. Radiographic alignment measures and patient-reported outcomes currently serve as the standard means to assess spinal alignment, deformity, and stability. Neurological examinations have served as qualitative measures for indicating muscle strength, motor deficits, and gait abnormalities. Three-Dimensional motion analysis is increasingly being used to identify and measure gait and balance instability. Recently, techniques have been established to quantify balance characteristics described by Dubousset as the "cone of economy" (CoE). The relationship between radiographic alignment parameters and CoE balance measures of ADS patients before and after realignment surgery is currently unknown. 29 ADS patients treated with realignment surgery. Patients were evaluated at one week before realignment surgery and at their three-month follow-up examination. During each evaluation, patients completed self-reported outcomes (visual analog scales for pain, Oswestry Disability Index, SRS22r) and a functional balance test. Mean changes in dependent measures from before to after surgery were compared using paired t-tests. Pearson correlations were used to test for significant correlations between changes in radiographic and CoE measures. Significant improvements were found for all patient-reported outcomes, in several radiographic measures, and in CoE measures. Improvements of scoliosis Cobb angle, coronal pelvic tilt, lumbar lordosis, and thoracic kyphosis showed significant correlations with CoE sway and total distance measures at both the center of mass and center of the head. Improved radiographic alignment measures significantly correlated with improved CoE balance measures among ADS patients treated with realignment surgery at their three-month follow-up. These findings indicate that functional balance evaluations when used in conjunction with radiographic measurements, may provide a more robust and improved patient-specific sensitivity for postoperative assessments. CoE balance may represent a new measure of added value for surgical intervention of ADS.

The effect of scoliosis support orthosis bracing on adult spinal deformity patients: evaluation of gait and dynamic balance.

Non-operative treatment is regarded as the first-line therapy for patients with adult spinal deformity (ASD) without neurologic deficits or significant impairment. While there is high-level evidence supporting the use of rigid bracing in adolescent idiopathic scoliosis, there is a paucity of literature pertaining to the use of scoliosis support orthosis (SSO) in ASD patients. To investigate the impact of an SSO on pain, gait parameters, and functional balance measures in symptomatic ASD patients. Thirty ASD patients (26 Females, Age: 72.7, Cobb Angle: 47.1°) were evaluated on 3 different occasions: first day of bracing: baseline (Pre), and 45-min post fitting (Post45m), and after 8-weeks of bracing for 4 hours a day (Post8w). Each patient performed a 6-minute walk (over-ground gait), a dynamic balance test, and completed VAS, ODI, and SRS22r. Significant short- and long-term improvements using SSO were found in the 6-minute walk (Pre: 278.6; Post45m: 322.2; Post8w: 338.8 m, p<0.001), walking speed (Pre: 0.88; Post45m: 0.97; Post8w: 0.97 m/s, p<0.001), head total sway distance during the balance test (Pre: 81.33; Post45m: 68.63; Post8w: 60.72 cm, p=0.048), low-back pain (VAS: Pre: 5.5; Post45m: 3.5; Post8w: 3.3, p<0.001), and for the ODI (Pre: 41.9; Post45m: 32.9; Post8w: 30.1, p=0.005).This study demonstrated clinically significant improvements in PROMs, spatiotemporal gait measures, and functional balance measures after continuous use of a SSO. These improvements were observed immediately following brace-fitting and maintained at an 8-week follow-up. Given these results, it is reasonable to consider a SSO for conservative management of patients with mild symptoms of pain and deformity, and who have not yet progressed to meet surgical indications.

Virulence of major periodontal pathogens and lack of humoral immune protection in a rat model of periodontal disease.

OBJECTIVE: This study was designed to test the hypothesis that periodontal pathogens Tannerella forsythia and Porphyromonas gingivalis are synergistic in terms of virulence potential using a model of mixed-microbial infection in rats. MATERIALS AND METHODS: Three groups of rats were infected orally with either T. forsythia or P. gingivalis in mono-bacterial infections or as mixed-microbial infections for 12 weeks and a sham-infected group were used as a control. This study examined bacterial infection, inflammation, immunity, and alveolar bone loss changes with disease progression. RESULTS: Tannerella forsythia and P. gingivalis genomic DNA was detected in microbial samples from infected rats by PCR indicating their colonization in the rat oral cavity. Primary infection induced significantly high IgG, IgG2b, IgG1, and IgG2a antibody levels indicating activation of mixed Th1 and Th2 immune responses. Rats infected with the mixed-microbial consortium exhibited significantly increased palatal horizontal and interproximal alveolar bone loss. Histological examinations indicated significant hyperplasia of the gingival epithelium with moderate inflammatory infiltration and apical migration of junctional epithelium. The results observed differ compared to uninfected controls. CONCLUSION: Our results indicated that T. forsythia and P. gingivalis exhibit virulence, but not virulence synergy, resulting in the immuno-inflammatory responses and lack of humoral immune protection during periodontitis in rats.

Robotic assisted spinal surgery--from concept to clinical practice.

After several years of product development, animal trials and human cadaver testing, the SpineAssist--a miniature bone-mounted robotic system--has recently entered clinical use. To the best of the authors' knowledge, this is the only available image-based mechanical guidance system that enables pedicle screw insertion with an overall accuracy in the range of 1 mm in both open and minimally invasive procedures. In this paper, we describe the development and clinical trial process that has brought the SpineAssist to its current state, with an emphasis on the various difficulties encountered along the way and the corresponding solutions. All aspects of product development are discussed, including mechanical design, CT-to-fluoroscopy image registration, and surgical techniques. Finally, we describe a series of preclinical trials with human cadavers, as well as clinical use, which verify the system's accuracy and efficacy.

Nuclear DNA polymerases of human carcinomas.

Comparisons have been made of the DNA polymerases of normal human lung and cecum, primary carcinomas of human lung, breast, and cecum, and resting and regeneration rat liver. The picture for the normal human tissues is similar to the one for unstimulated rat liver, that for the human carcinomas resembles regenerating rat liver. The human tissues contain two polymerases with sedimentation coefficients of about 3 and 7 S, the enzymes are restricted to the nucleus, and the specific activities of the 7 S polymerase, but not of the 3 S enzyme, are elevated in the cancers. Just as with the regenerating rat liver polymerases, the 3 S activity of a bronchogenic carcinoma is unaffected by cytosine arabinoside 5'-triphosphate and only little reduced by novobiocin, whereas DNA synthesis by the 7 S enzyme is abolished by both compounds. A variety of other inhibitory agents have similar effects on the 7 S polymerases of the human carcinomas and regenerating rat liver.

The 7.1 S nuclear DNA polymerase and DNA replication in intact liver.

Just as after 70% hepatectomy, the activity of the 7.1 S DNA polymerase, but not the 3.2 S polymerase, is elevated in liver nuclei from unoperated animals in which hepatic DNA replication has been induced with a mixture of biochemicals or by a dietary manipulation. Again as with regenerating liver, the stimulated intact livers show a relationship between the increases in the enzyme activity and thymidine incorporation in vivo over a wide range of hepatic responses. These observations are consistent with a role for the 7.1 S activity in nuclear DNA replication. Cytosine arabinoside 5'-triphosphate and novobiocin can be used to distinguish between the 3.2 S and 7.1 S polymerases from nuclei of stimulated intact liver as well as of regenerating liver.

Kyphoplasty in the treatment of osteolytic vertebral compression fractures as a result of multiple myeloma.

PURPOSE: We prospectively evaluated the safety and efficacy of kyphoplasty in the treatment of osteolytic vertebral compression fractures resulting from multiple myeloma. The principle symptoms in multiple myeloma result from bone destruction, especially the spine. Kyphoplasty is a new technique that involves the introduction of inflatable bone tamps (IBT) into the vertebral body. The purpose of the IBT is to restore the vertebral body back toward its original height, while creating a cavity that can be filled with highly viscous bone cement. PATIENTS AND METHODS: Fifty-five consecutive kyphoplasty procedures were performed in 18 patients with osteolytic vertebral compression fractures resulting from multiple myeloma. Cement leakage and any complications were recorded. Early objective analysis was made by comparing preoperative and latest Short Form 36 Health Survey scores. Height restoration was estimated by measuring vertebral height on lateral radiographs. RESULTS: The mean age of patients was 63.5 years, mean duration of symptoms was 11 months, and mean follow-up was 7.4 months. There were no major complications related directly to use of this technique. On average, 34% of height lost at the time of fracture was restored. Asymptomatic cement leakage occurred at two (4%) of 55 levels. Significant improvement in SF36 scores occurred for Bodily Pain (23.2 to 55.4, P =.0008), Physical Function (21.3 to 50.6, P =.0010), Vitality (31.3 to 47.5, P =.010), and Social Functioning (40.6 to 64.8, P =.014). CONCLUSION: Kyphoplasty was efficacious in the treatment of osteolytic vertebral compression fractures resulting from multiple myeloma. Kyphoplasty is associated with early clinical improvement of pain and function as well as some restoration of vertebral body height.

Prevention by tetrandrine of spontaneous development of diabetes mellitus in BB rats.

Treatment of BB rats with the plant alkaloid tetrandrine (20 mg.kg-1.day-1), a novel anti-inflammatory compound, from 35 to 120 days of age reduced the cumulative incidence of spontaneous diabetes from 75.5 to 10.9% (P less than 0.001). Dose-response studies with 0, 5, 10, and 20 mg.kg-1.day-1 of tetrandrine from 35 to 130 days resulted in spontaneous diabetes in 84.2, 63.1, 31.6, and 5.3% of the rats, respectively. When the start of treatment with 20 mg.kg-1.day-1 tetrandrine was delayed until 70 days of age, there was a significant reduction of the incidence of diabetes from 63.1 to 28.6% (P less than 0.01). Histological examination of the pancreases from tetrandrine-treated rats showed a lesser degree of insulitis than controls (P less than 0.01). Drug toxicity was not seen in the rats, as assessed by appearance, behavioral change, organ histology, and blood chemistry. These results provide some hope that tetrandrine may be of value in preventing diabetes and treating newly diagnosed diabetic subjects, either by itself or in combination with a more potent immunosuppressive agent.

Effect of FK 506 on spontaneous diabetes in BB rats.

From days 30-120 after birth, 59 BB rats were treated with water (n = 20) or FK 506 in intragastric doses of 1 mg.kg-1.day-1 (n = 19) or 2 mg.kg-1.day-1 (n = 20). Diabetes developed in 75, 15, and 0% of the 3 groups, respectively. Animals protected from diabetes by FK 506 had normal intraperitoneal glucose tolerance tests, virtual absence histopathologically of autoimmune insulitis, and normal pancreatic insulin content. Forty-five to 75 days after stopping FK 506, approximately 75% of the rats that were diabetes free at 120 days remained so.

The involvement of orbitofrontal cerebrum in cognitive tasks.

Although the frontal lobes are frequently associated with high-level cognitive functions, patients with significant frontal damage often maintain normal "intelligence". While recent research has clarified some aspects of this enigma, specific questions remain concerning the nature of the deficit in these patients and its relation to lesion localization within the frontal lobes. A group of psychiatric patients who had undergone prefrontal leucotomy 25 years earlier and whose frontal lesions were bilateral and maximal orbitofrontally were evaluated. Sixteen leucotomized schizophrenics, divided into three groups based upon recovery after psychosurgery, were compared to two control groups: (1) non-leucotomized chronic schizophrenics; (2) normal subjects. Four tests were administered: Wechsler Adult Intelligence Scale, Wisconsin Card Sorting test, Visual Metaphor test, and the Visual Verbal test of abstraction. The results suggest that orbitofrontal pathology does cause impaired performance on certain cognitive tests, which appeared independent of IQ measures.

Effect of probucol on development of diabetes mellitus in BB rats.

Insulin-dependent diabetes mellitus (IDDM) results from an inflammatory process leading to destruction of the insulin-producing beta cells of the pancreas. Genetically mediated autoimmune processes are considered the most likely explanation for IDDM in humans, while viral infections, toxic agents, nutritional alterations and stress are also considered possibilities. The precise mechanisms by which autoimmunity, infections, toxins or other agents produce beta cell damage are not known. Toxin-induced diabetes in animals can be prevented by antioxidant therapy, while an agent that inhibits hydroxyl radical formation, desferrioxamine, extends the survival time of free allotypic islets in nonobese diabetic mice. The BB/W rat develops IDDM secondary to a pervasive autoimmune defect. This well-studied animal model develops IDDM with a highly predictable frequency and timing. This study describes the effects of the potent antioxidant, probucol, on the development of diabetes in BB rats by introducing it into standard rat chow at a 1% concentration at the time of weaning, and continuing this feeding schedule through 160 days of life. Control rats from split litters received standard chow only. Diabetes developed in 86.2% of the control rats at a mean age of 90.4 days. Probucol administration was associated with a reduction to 62% and a delay in diabetes diagnosis to 99.6 days. These very preliminary results suggest that probucol may be altering the inflammatory process, resulting in beta cell destruction in these genetically diabetes-prone rats.

High degree of satellite association and decreased nucleolar organizer activity in cystic fibrosis subjects.

The effect of colchicine at concentrations of 0.25 X 10(-6) M, 1.0 X 10(-6) M, and 2.0 X 10(-6) M on the degree of satellite association (SA) was estimated in phytohemagglutinin-stimulated lymphocytes of individuals in the following groups: cystic fibrosis (CF) children, obligatory CF heterozygotes, control children, and control adults. In all four groups increasing colchicine concentration caused a higher degree of SA. The degree of SA differed between the two control age groups (children vs adults) only at the lowest concentration. CF patients had a significantly higher degree of SA than CF heterozygotes and than control individuals at all colchicine concentrations; CF heterozygotes had a significantly higher degree of SA than control adults at the low and intermediate concentrations. There was a strong interaction between genotype and colchicine concentration: the differences between the CF patients and the control individuals were most distinct at the intermediate concentration and between the carriers and the control individuals at the low colchicine concentration. Colchicine had no effect on the activity of the nucleolar organizer regions (NORs), as measured by the frequency of the silver-stained NORs (AgNORs), while the frequency of AgNORs in CF patients was significantly lower as compared to control individuals. Yet, the increase in the degree of SA caused by the CF mutant allele involved specifically the satellited chromosomes carrying active NORs.

Propranolol: an unrecognized cause of central nervous system dysfunction in patients undergoing cardiopulmonary bypass.

An organic mental syndrome developed in a patient soon after he underwent repair of a dissecting thoracic aortic aneurysm. The operation was accomplished with cardiopulmonary bypass. Initially, the mental changes were thought to be related to the operation. However, they subsequently were shown to be associated with propranolol. The potential role of propranolol in inducing central nervous system disturbances is emphasized, and the literature on the subject is reviewed.

Outpatient surgery in pediatric urology patient.

Outpatient surgery in children with straightforward surgical problems has proved to be safe and cost effective. We have analyzed our experience in 138 consecutive "short-stay" surgical patients in terms of (1) cost effectiveness, (2) surgical procedure, and (3) complications. Selection of a patient for outpatient surgery requires a thorough preoperative evaluation as well as close cooperation between surgeon, anesthesiologist, and operating room staff.

Synergy between tetrandrine and FK506 in prevention of diabetes in BB rats.

Delayed administration of tetrandrine, a novel broad-spectrum anti-inflammatory agent, to BB rats at a dosage schedule of 20 mg kg-1 day-1 from 79 days of age reduced the cumulative incidence of diabetes from 73.1 to 41.7% (p < 0.01). Brief treatment with the potent immunosuppressive agent FK506 at a dosage schedule of 0.5 mg kg-1 day-1 from 79 days of age for 5 days had no significant effect on the cumulative incidence of diabetes (66.7%, p > 0.1). However, the combination of tetrandrine and FK506 in the afore-mentioned dosage schedules reduced the incidence of diabetes to only 3.6% (p < 0.001). These results suggest that the strong synergy between tetrandrine and FK506 may offer a safe and effective therapeutic strategy for the treatment of patients with recent onset or imminent IDDM.

Laparoscopic lumbar interbody spinal fusion.

Laparoscopic ALIF is an evolving technique requiring the participation of a laparoscopic surgeon experienced in advanced laparoscopic techniques and knowledgeable in anterior lumbar spinal exposures. Initial enthusiasm for this technique was fostered by the development of interbody fusion devices and a method of exposing the anterior lumbar spine, which takes advantage of the ability of minimally invasive surgeries to improve exposure and visualization while minimizing collateral tissue damage and injury to healthy tissue. Preliminary studies have demonstrated laparoscopic ALIF feasibility. These same studies have been able to prove only minor advantages with the laparoscopic versus open technique using the current implants and bone grafting techniques for single-level disc disease. General acceptance of laparoscopic ALIF awaits further investigation. Reasons for a lack of general acceptance include the expense of the interbody fusion devices and laparoscopic equipment, the unfamiliarity of this advanced laparoscopic technique to spine and general surgeons, and the steep learning curve of the procedure. Intraoperative complications that arise are often severe, such as vascular injuries. Many skeptics appropriately believe that initial enthusiasm and zealousness must be tempered with scientific effort that provides data from long-term follow-up. For laparoscopic ALIF to gain general acceptance, randomized comparisons of laparoscopic ALIF to open ALIF and posterior lumbar spinal fusion and controlled studies with long-term follow-up documenting symptomatic outcome variables and spinal fusion rates must be completed. As new modalities are developed, minimally invasive techniques may facilitate their utility. The indications, procedures, and surgical principles of ALIF are unchanged, and physicians must not invent indications to justify the technique; however, eventually we may be able to redefine the indications to take full advantage of the endoscopic techniques and biological advances.

Arthroscopically assisted arthrodesis for osteoarthrotic ankles.

Arthroscopically assisted arthrodesis of the ankle was performed in nineteen patients who were selected because they had osteoarthrosis with minimum or no deformity of the ankle. After arthroscopic resection of the synovial membrane, the subchondral bone, and cartilage from the tibial, fibular, and talar articular surfaces, three percutaneous, cannulated, cancellous screws were used for internal fixation. Of these nineteen patients, ten had radiographic evidence of union by the second postoperative month; five, by the third; one, by the fifth; and one, by the sixth. Two patients had a non-union, but a successful open arthrodesis was subsequently performed on one of these patients. At two years, the scoring system of Mazur et al. indicated a poor result in one patient (after a non-union), a fair result in two, a good result in four, and an excellent result in twelve patients. Arthroscopically assisted arthrodesis of the ankle produces good results in patients who have osteoarthrosis of the ankle with minimum or no deformity, and the immediate postoperative morbidity is of very short duration.

Laparoscopic lateral L4-L5 disc exposure.

BACKGROUND: The anterior laparoscopic approach requires precarious dissection around the iliac vessels to expose the L4-L5 level. Furthermore, a retroperitoneal endoscopic approach to the L4-L5 level requires a technically demanding dissection to access the L5-S1 disc space. A unique lateral laparoscopic approach to the L4-L5 disc space allows concurrent access to the L5-S1 space while avoiding major dissection around the iliac vessels. This article describes this novel lateral approach and reviews the initial clinical outcomes. METHODS: Between January 1999 and April 2000, five patients underwent laparoscopic lateral L4-L5 disc exposure at the Cleveland Clinic Foundation. All charts were reviewed retrospectively. Mean values +/- standard deviation were determined for patient demographics and operative characteristics. A standard five-port laparoscopic technique was used. The sigmoid colon was retracted medially with an endoloop. The retroperitoneum was entered and the ureter and left iliac artery were retracted medially, whereas the psoas was retracted laterally. Fluoroscopy delineated the L4-L5 disc space allowing discectomy and cage insertion. Postoperatively, subjective patient satisfaction was obtained and radiologic evidence of fusion was assessed. RESULTS: All five patients were males, with a mean age of 47.4 +/- 7 years and a body mass index of 30 +/- 6 kg/m2. Four patients had an L4-L5 and L5-S1 fusion and one patient had an L4-L5 and L3-L4 fusion. Mean operative time was 349 +/- 32 min, with a mean blood loss of 210 +/- 74 cc. There were no intraoperative complications and no conversions, and postoperatively all patients were started on a clear liquid diet on postoperative day 1. The mean length of stay was 3.4 +/- 0.9 days. Patients returned to work in a mean of 12 +/- 7 weeks. All patients had evidence of fusion on their radiologic follow-up. Four patients were pain free, whereas one patient required intermittent narcotics at 1-year follow-up. CONCLUSIONS: For multilevel fusions including the L4-L5 disc space, the lateral laparoscopic exposure is a safe and efficacious procedure allowing simultaneous access to multiple disc spaces while avoiding the sympathetic chain, ureter, and major vascular structures. The lateral approach affords excellent exposure for accurate deployment of the appropriate orthopedic hardware.

Endoscopic approaches to metastatic thoracic disease.

Traditional approaches to thoracic metastases and spinal cord compression have been well worked out and validated in the literature. Anterior decompression is clearly superior to laminectomy; vertebrectomy and reconstruction are indicated for sagittal collapse, instability, and pain; and surgical decompression is necessary in cases of bony impingement. The role of endoscopic and minimally invasive techniques in treatment of metastatic disease is evolving. Dr. Lieberman advocates the use of thoracoscopic anterior approaches as the principal application in these patients, whereas Dr. McLain has found that endoscopic assistance has vastly improved his results with posterolateral decompression. The two authors weigh the relative advantages and disadvantages of these approaches for the selected patient with metastatic thoracic disease.

Anterior vertebral body screw pullout testing. A comparison of Zeilke, Kaneda, Universal Spine System, and Universal Spine System with pullout-resistant nut.

STUDY DESIGN: A biomechanical study of pullout of anteriorly implanted screws in cadaveric vertebral bodies. OBJECTIVES: To investigate and compare the pullout strength of the Zielke, Kaneda, Universal Spine System (USS) pedicle screw, and USS pedicle screw with a new pullout-resistant nut. SUMMARY OF BACKGROUND DATA: A common problem with anterior purchase regardless of the implant system is screw pullout at the proximal and distal ends of multilevel constructs. There is limited information on a solution to this problem. METHODS: The L1 to L4 vertebral bodies from four cadavers had one each of Zielke and Kaneda pedicle screws (Acromed Corp., Cleveland, OH), USS pedicle screw (Synthes Spine, Paoli, PA), and USS pedicle screw with pullout-resistant nut implanted transversely across the center of the vertebral body with bicortical purchase in a similar fashion as would be used clinically. The screws were extracted using a servohydraulic material testing system. The maximum axial forces were recorded. RESULTS: The Zielke and Kaneda screws had no significant difference in mean pullout strength (P = 0.542). The USS screw alone was less strong (P = 0.009). The USS screw and pullout-resistant nut increased the pullout strength by twofold (P = 0.00006). In the screw pullout tests, the mode of failure was at the screw thread's interface. The USS screw and pullout-resistant nut failed by imploding the body around the nut. With the USS screw and pullout-resistant nut, the pullout strength was determined by the compressive strength of the bone. CONCLUSIONS: The addition of a pullout-resistant nut to an anterior vertebral body screw improves the pullout strength by twofold and changes the mode of failure to rely ultimately on the inherent vertebral body strength rather than the screw's characteristics. The addition of a pullout-resistant nut may be applicable to multilevel implant constructs to prevent screw pullout at the top and bottom.