Fracture risk of vertebral bodies after cryosurgery using a miniature cryoprobe: A biomechanical in-vitro analysis on human bones.

INTRODUCTION: Due to spinal instability and compressive neurologic deficits surgical management is sometimes necessary in patients with metastatic spinal lesions. However, in some cases open surgery is not possible and minimally invasive procedures, like cryoablation, are needed. The aim of the current study was to investigate whether a miniature cryoprobe provides adequate tissue cooling in vertebrae and to evaluate the direct impact of cryosurgery on vertebral body stability. MATERIALS AND METHODS: Twelve thoracic vertebral bodies were harvested from fresh cadavers. After documenting bone density cryoablation was performed in six vertebral bodies according to a standardized procedure. Afterwards temperature inside the vertebral body and maximum breaking force were measured in the control and experimental groups. RESULTS: Required temperature of -50° was reached in all areas. There was a significant correlation between maximum breaking force and measured bone density (p= 0.001). Mean breaking force within the experimental group was 5047 N (SD = 2955 N) compared to 4458 N (SD = 2554 N) in the control group. There were no observable differences in maximum breaking force between both groups. CONCLUSION: Miniature cryoprobe can deliver adequate tissue cooling to -50°C in vertebral bodies. The procedure does not seem to influence breaking force of the treated bones in-vitro. Therefore, using miniature probes cryosurgery may provide a valuable alternative to conventional surgical resection of neoplastic diseases as well as of benign locally aggressive bone tumors.

[Complication analysis of spinal interventions in adult central movement disorders and scoliosis]. / Komplikationsanalyse von spinalen Eingriffen bei adulten zentralen Bewegungsstörungen und Skoliosen.

BACKGROUND: Adult central movement disorders, malpostures, and scolioses can have their cause in various neurological underlying diseases such as Morbus Parkinson, Pisa syndrome, or segmental dystonia. Important clinical characteristics are marked postural distortions such as camptocormia (bent spine) or laterocollis. In cases of these adult scolioses, surgical spine treatment puts high demands on the surgeon. Surgery in Parkinson's disease, for example, is associated with serious surgery-specific as well as general complications. The more rarely occurring Pisa syndrome is an entity primarily requiring medical therapy. PATIENTS AND METHODS: A series of ten case reports of patients with Morbus Parkinson and Pisa syndrome who underwent spinal surgery is presented and discussed. From these reports, treatment recommendations have been derived and complemented by references from the literature. An extensive MEDLINE search was performed for this purpose. RESULTS AND CONCLUSION: In patients suffering from Parkinson's disease, even minor surgical interventions can lead to instability of whole spine segments or even the entire spine. Implant loosening, adjacent segment instability, general perioperative complications, and progressive malposture due to disease progress can bring forth disastrous treatment courses. Spinal fixation should be performed long-segmented in combination with ventral stabilisation. Due to osteoporosis, pedicle screw cement augmentation is recommended in this collective. If the diagnosis of Pisa syndrome is established, an optimised preoperative preparation should be initiated in close cooperation with neurologists. In many cases medical therapy is sufficient and surgical interventions can be avoided.

The current management of lumbar spondylolisthesis.

Lumbar spondylolisthesis can lead to disabling low back pain and neurological deficits. This review details the clinical history, neurological examination, clinical presentation, imaging modalities, and current management standards for lumbar spondylolisthesis. Based on the available clinical trials, there is evidence that, compared with nonsurgical care, the surgical treatment of symptomatic spondylolisthesis offers a significant clinical benefit in the presence of progressive neurological deficits; cauda equina syndrome; failure of an adequate response to conservative therapy: radiographic instability with neurological symptoms; radiographic progression of subluxation to greater than grade II; symptomatic grades III, II, or spondyloptosis; and unremitting pain that affects the quality of life. Optimizing the diagnostic paths and surgical indications and standardizing both the surgical procedures as well as the outcome measurements with validated instruments should assist the spine care community in acquiring data that are essential for providing the best evidence-based treatment while reducing or eliminating procedures that lack evidence of either efficacy or value.

[Is height restoration possible with a comparatively smaller amount of cement in radiofrequency kyphoplasty using a monopedicle approach?]. / Ist eine Höhenrekonstruktion mit vergleichsweise wenig Zement für die Radiofrequenz-Kyphoplastie über einen monopedikulären Zugang möglich?

BACKGROUND: Percutaneous cement augmentation systems have been proven to be an effective treatment for vertebral compression fractures in the last 10 years. A special form available since 2009 is the radiofrequency kyphoplasty (RF) in which the applied energy raises the viscosity of the cement. The aim of this study is to find out if a smaller cement amount in radiofrequency kyphoplasty can also restore vertebral body height in osteoporotic vertebral compression fractures. METHODS: The treatment was minimally invasive using the StabiliT® vertebral augmentation system by DFine. In a retrospective study from 2011 to January 2012, 35 patients underwent RF kyphoplasty for 49 fresh osteoporotic vertebral compression fractures. From the clinical side the parameters, demographics and pain relief using a visual analogue scale (VAS: 0 to 100 mm) were collected. For the radiological outcome the vertebral body height (anterior, mean and posterior vertebral body height with kyphosis angle) after surgery and after three months was measured and compared to the cement volume. RESULTS: All patients still had permanent pain on the fractured level after conservative treatment. The time from initial painful fracture to treatment was 3.0 weeks ± 1.3. Average visual analogue scale results decreased significantly from 71 ± 9.2 preoperatively to 35 ± 6.2 postoperatively (p < 0.001) and to 30 ± 5.7 (p < 0.001) after three months. With a mean cement volume in the thoracic spine of 2.9 ± 0.7 ml (1.8-4.1) and lumbar spine of 3.0 ± 0.7 ml (2.0-5.0) we had a significant vertebral body height restoration. Anterior and mean vertebral body heights significantly increased by an average of 2.3 and 3.1 mm, kyphosis angle significantly decreased with an average of 2.1° at three-month follow-up (p < 0.05). In two vertebrae (4.1 %) a minimal asymptomatic cement leakage occurred into the upper disc. In two patients (5.7 %) we had new fractures in the directly adjacent segment that were also successfully treated with radiofrequency kyphoplasty. CONCLUSION: With a mean cement volume of 3.0 ml radiofrequency kyphoplasty achieves rapid and short-term improvements of clinical symptoms with a significant restoration of vertebral body height. There was no correlation between restoration of vertebral body height and pain relief. With a cement leakage of 4.1 % RF kyphoplasty is a safe and effective minimally invasive percutaneous cement augmentation procedure. Our data confirm the higher safety described in literature for kyphoplasty in contrast to vertebroplasty.

Potentialities and limitations of a database constructing three-dimensional virtual bone models.

BACKGROUND: 3D bone reconstructions performed during general clinical practice are of limited use for preclinical research, education, and training purposes. For this reason, we are constructing a database of human 3D virtual bone models compiled from computer tomography (CT) scans. MATERIALS AND METHODS: CT data sets were post-processed using Amira(®) 5.2 software. In each cut, bone structures were isolated using semiautomatic labeling program codes. The software then generated extremely precise 3D bone models in STL format (standard triangulated language). These bone models offer a sustainable source of information for morphologic studies and investigations of biomechanical bony characteristics in complex anatomic regions. Regarding educational value and student acceptance models were introduced during bedside teaching and evaluated by medical students. RESULTS: The current database is comprised of 131 pelvises and 120 femurs (ø 60 years, ø 172 cm, ø 76 kg), and is continuously growing. To date, 3D morphometric analyses of the posterior ring and the acetabulum have been successfully completed. Eighty students (96 %) evaluated instruction with virtual 3D bone models as "good" or "very good". The majority of students want to increase learning with virtual bone models covering various regions and diseases. CONCLUSION: With consistent and steadily increasing case numbers, the database offers a sustainable alternative to human cadaver work for practical investigations. In addition, it offers a platform for education and training.

Is it feasible to rely on intraoperative X ray in correcting hallux valgus?

BACKGROUND: The aim of the study was to prove whether the intraoperatively taken fluoroscopy pictures compared to the X rays taken 8 weeks and 3 months postoperatively picture the achieved correction reliably. METHOD: In a prospective study, the pre- and postoperative standing foot X rays as well as the intraoperatively taken fluoroscopy pictures of 31 patients were analysed. The intermetatarsal angle (IMA) and the hallux valgus angle (HVA) were measured. In all cases, a tarso-metatarsal joint I arthrodesis combined with a distal soft tissue release was performed. The mean age was 54 (17-73) years. RESULTS: There was no significant difference between the measured angles in intraoperative fluoroscopy and standing X rays postoperatively taken. CONCLUSIONS: Despite the consideration that fluoroscopic pictures lack the loading criteria, we found reliable results in IMA and HVA.

Injuries and overuse syndromes in powerlifting.

Powerlifting is a discipline of competitive weightlifting. To date, no investigations have focused on pain encountered during routine training. The aim of the study was to identify such pain, assign it to particular exercises and assess the data regarding injuries as well as the influence of intrinsic and extrinsic factors. Data of 245 competitive and elite powerlifters was collected by questionnaire. Information regarding current workout routines and retrospective injury data was collected. Study subjects were selected from 97 incorporated powerlifting clubs. A percentage of 43.3% of powerlifters complained of problems during routine workouts. Injury rate was calculated as 0.3 injuries per lifter per year (1 000 h of training=1 injury). There was no evidence that intrinsic or extrinsic factors affected this rate. Most commonly injured body regions were the shoulder, lower back and the knee. The use of weight belts increased the injury rate of the lumbar spine. Rate of injury to the upper extremities was significantly increased based on age >40 years (shoulder/p=0.003, elbow/p=0.003, hand+wrist/p=0.024) and female gender (hand+wrist/p=0.045). The daily workout of a large proportion of powerlifters is affected by disorders which do not require an interruption of training. The injury rate is low compared to other sports.

Clinical outcomes and quality of life 1 year after open microsurgical decompression or implantation of an interspinous stand-alone spacer.

BACKGROUND: Interspinous stand-alone implants are inserted without open decompression to treat symptomatic lumbar spinal stenosis (LSS). The insertion procedure is technically simple, low-risk, and quick. However, the question remains whether the resulting clinical outcomes compare with those of microsurgical decompression, the gold standard. MATERIAL AND METHODS: This prospective, comparative study included all patients (n=36) with neurogenic intermittent claudication (NIC) secondary to LSS with symptoms improving in forward flexion treated operatively with either interspinous stand-alone spacer insertion (Aperius (®); Medtronic, Tolochenaz, Switzerland) (group 1) or microsurgical bilateral operative decompression (group 2) between February 2007 and November 2008. Data (patient data, operative data, COMI, SF-36 PCS and MCS, ODI, and walking tolerance) were collected preoperatively as well as at 6 weeks, at 3, 6, and 9 months, and at one year follow-up (FU). All patients had complete FU over 1 year. RESULTS: Compared to preoperative measurements, surgery led to improvements of all parameters in the entire collective as well as both individual groups. There were no statistically relevant differences between the 2 groups over the entire course of FU. However, improvements in the ODI and SF-36 MCS were not significant in group 1, in contrast to those of group 2. Also, although in group 1 the improvements in leg pain (VAS leg) were still significant (p<0.05) at 6 months, this was no longer the case at 1 year FU. In group 1 at 1 year FU an increase in leg pain was observed, while in group 2, minimal improvements continued. Walking tolerance was significantly improved at all FU times compared to preoperatively, regardless of group (p<0.01). At no time there was a significant difference between the groups. In group 1, admission and operative times were shorter and blood loss decreased. The complication rate was 0% in group 1 and 20% in group 2, however reoperation was required by 27.3% of group 1 patients and 0% of group 2. CONCLUSION: Implantation of an interspinous stand-alone spacer yields clinical success comparable to open decompression, at least within the first year of FU. The 1-year conversion rate of 27.3% is, however, decidedly too high.

The present role of vertebroplasty and kyphoplasty in the treatment of fresh vertebral compression fractures.

Vertebroplasty (VP) and kyphoplasty (KP) are minimally invasive vertebral augmentation procedures for the treatment of fresh vertebral compression fractures (VCFs) associated with osteoporosis, trauma, malignant conditions, hemangiomas, and osteonecrosis. During these procedures, bone cement (e.g., polymethylmethacrylate) is percutaneously injected into the vertebral body. Systematic reviews of both procedures have shown significantly improved back pain and quality of life compared to conservative therapy. Direct comparison between VP and KP is not possible because of the lack of prospective randomized data comparing the two procedures. Both appear to improve patient functional status in most studies, although it is difficult to pool the available data because of differing measurement scales. With increasing popularity of both techniques, particularly over the past ten years, a rising number of publications have detailed potential complications secondary to cement extravasation, from compression of neural elements to venous embolism. Overall complication rates for both procedures are low. Systematic reviews have found significantly higher rates of cement leakage after VP (40%) versus KP (8%), with 3% of VP leaks being symptomatic. The evidence for increased risk of adjacent level fracture after these procedures compared to conservative treatment is inconclusive. When performed by a well-trained practitioner in appropriately selected patients, vertebroplasty and kyphoplasty are both safe and effective treatments for fresh vertebral compression fractures. Results from ongoing randomized controlled trials will provide further detailed information about both procedures in the future.

The future of surgical orthopaedics of the knee.

Over the past two decades, orthopaedics has gone through major changes, principally in the surgical treatment options for articular defects of the knee. This paper explores the advantages and shortcomings of the current surgical treatment modalities for cartilaginous defects in the knee. Emphasis is placed on current techniques in knee arthroplasty, including a view on the future of orthopaedic knee surgery.

[Spondylodiscitis - an interdisciplinary challenge]. / Spondylodiszitis - eine interdisziplinäre Herausforderung.

HISTORY AND ADMISSION FINDINGS: A 21-year-old man presented with severe lumbar back pain and progressive paraparesis with clinical signs of spondylitis. Laboratory findings revealed elevated infectious parameters. Because of a positive Mantoux-Test he had been treated with quadruple tuberculostatic drugs for eight weeks without prior identification of the causative pathogen. INVESTIGATIONS: Magnetic resonance imaging of the spine revealed a multisegmental spondylitis of the lumbar vertebrae (L3 - L5) with epidural empyema. Computed tomography (CT) of the abdomen confirmed large bilateral abscesses in the psoas muscles. TREATMENT AND COURSE: The findings supported the diagnosis of spondylitis. The antibiotic regimen was continued. CT-guided drainage was placed in both psoas muscles. Laminectoma of L3 - 5 and dorsal spondylodesis of L2 - S1 were performed immediately. Mycobacterium tuberculosis was cultured from the intraoperative biopsies and treated according to the drug sensitivity test. After further surgical debridment and corporectomy of L4 and L5 the infection was successfully treated. Ten weeks after admission the patient was transferred to a neurologic rehabilitation unit for mobilization. CONCLUSION: Spondylodiscitis treatment is complex and requires a multidisciplinary approach.

[Degeneration and osteoporosis of the spine. Is there a modified procedure?]. / Degeneration und Osteoporose der Wirbelsäule. Andert sich die Vorgehensweise?

Reduced bone quality due to osteoporosis poses a fundamental problem in spine surgery instrumentation. The consequences observed most often are insufficient implant anchoring and adjacent fractures. In cases of manifest osteoporosis, several modern anchoring possibilities are at our disposal that, to differing degrees, increase the stability of the instrumentation. Cement augmentation of a fractured vertebra by means of kyphoplasty or vertebroplasty verifiably leads to significantly better pain reduction than conservative treatment does, at least in the short-term postoperative course. A difference between these two techniques has not yet been substantiated. The rate of adjacent fractures occurring after cement augmentation is not higher than in conservatively treated patients.

Effectiveness, security and height restoration on fresh compression fractures--a comparative prospective study of vertebroplasty and kyphoplasty.

INTRODUCTION: Painful fractures of the spine pose a serious clinical problem which gains in importance with the increasing ageing of our population. When conservative treatment of these fractures fails, with vertebroplasty and kyphoplasty we have two percutaneous minimally invasive stabilising procedures at our disposal. PATIENTS AND METHODS: We performed a prospective study of 90 patients with fresh osteoporotic vertebral fractures who had been treated with vertebroplasty or kyphoplasty in our clinic between January 1, 2005, and December 31, 2007. Clinical analysis included Oswestry score and VAS index; the vertebral body height restoration (mean vertebral body height, kyphosis angle, anterior/posterior edge) was evaluated radiologically; furthermore, all occurring complications were recorded. The follow-up time was 1 year, 80 patients could be examined at follow-up; 8 patients had died of a tumour disease, lost to follow-up were 2.2%. RESULTS: Both procedures succeeded in significantly (p<0.001) increasing quality of life (Oswestry score) and reducing pain (VAS). Following vertebroplasty there were two cases of cement leakage into the spinal canal with consecutive paraparesis which disappeared completely after the cement had been surgically removed. Altogether, 11 adjacent level fractures were observed, 4 in the vertebroplasty and 7 in the kyphoplasty group. CONCLUSION: This study compares vertebroplasty and kyphoplasty with regard to their effectiveness, safety, and restoration of vertebral body height, and complications. There were no differences between the groups with regard to quality of life and pain improvement, but the rate of serious complications was higher after vertebroplasty. Mean vertebral body height restoration at 1 year follow-up was significantly higher (p<0.05) in the kyphoplasty group. It remains to be seen in future long-term studies whether or not restoration of vertebral body height has an effect on the clinical result.

Dorsal corporectomy in a Ewing sarcoma situated in the pedicle of the L5 vertebral body.

The clinical case of a 34-year-old patient is presented who was diagnosed with Ewing sarcoma in the right pedicle of the L5 vertebral body on the basis of persisting dorsolumbar pain. Staging examinations including CT scan of the thorax and abdomen as well as bone scintigraphy were inconspicuous. The patient underwent 6 cycles of neoadjuvant chemotherapy (VIDE, similar to Euro Ewing 99). Presurgically, embolisation of the L4 and L5 vertebral bodies was performed on both sides. The tumour was removed via a dorsal approach with corporectomy of L5 and resection of the right nerve root of L5. The defect was bridged by a titanium cage filled with bone cement; a dorsal L4-S1 instrumentation was performed. Early postoperative X-rays showed a screw dislocation in S1, making a revision intervention and screw replacement necessary. For additional fixation, S2 was instrumented. Histopathology classified the tissue samples as containing no active tumour cells. Surgery was followed by additional chemotherapy. The patient has remained free of recurrence until now. The aim of this case report is to call attention to the unusual site of the Ewing sarcoma as well as to discuss therapy options, especially dorsal corporectomy, and the prognosis together with a review of the most current literature.

[Erysipel at the lower leg combined with a peripheral peroneus nerve palsy--an unusual occurrence]. / Ein Erysipel am Unterschenkel kombiniert mit einem peripheren Peroneusschaden--Ein seltenes Ereignis.

We present the clinical case of a fifty-year-old man who presented two times with a foot elevator paresis and an erysipel first on the right and after two months on the left side. Afterwards, we carried out a thorough case history with the help of clinical, radiological and magnetic resonance imaging. Even so the clinical pathology of the foot elevator paresis could not be manifested. A compartment syndrome could be discounted. In the context of the second stay during a neurology examination on both legs electromyography was performed and the nerve speed was tested. A peripheral peroneus paresis of unknown level and of unknown aetiology was demonstrated. The erysipel regressed rapidly under intravenous ampicillin antibiotics while the peroneus paresis was unchanged. The patent was released with a peroneus splint on both sides. With this case report we would like to point out the causes of peripheral peroneus paresis with regard to an additional erysipel. This case report is discussed regarding the possible aetiopathology and the current literature.

Surveillance of nosocomial transmission of Candida albicans in an intensive care unit by DNA fingerprinting.

The frequency of nosocomial transmission of the opportunistic fungal pathogen Candida albicans in an intensive care unit was tested by DNA fingerprinting of 91 isolates from 32 hospitalized patients with the mid-repetitive Ca3 DNA probe. This showed that serial isolates of C. albicans from individual patients belonged to genetically distinct strains. In comparison with nosocomial bacterial pathogens, the transmission of C. albicans in an intensive care unit occurred at a much lower frequency. In conclusion, the threat of C. albicans infection does not lie within the hospital, but in commensal isolates. These findings are relevant for infection control practices.

A case of equine granulocytic ehrlichiosis provides molecular evidence for the presence of pathogenic anaplasma phagocytophilum (HGE agent) in Germany.

Based on seroprevalence studies and tick infection rates, tick-borne human granulocytic ehrlichiosis (HGE) is thought to occur in Germany, but to date no clinical case has been detected. Reported here are the first ehrlichial sequences derived from a German horse that fell ill with granulocytic ehrlichiosis. The analysis of three different genes (16S rRNA gene, groESL, and ankA) revealed up to 100% identity with ehrlichial sequences derived from patients with HGE in other countries or from infected ticks in Germany. Thus, the current lack of clinical cases of HGE in Germany is unlikely to result from the absence of pathogenic granulocytic ehrlichiae strains in German ticks.