Marginal contribution of UKS- versus TKA in varus arthritis of the knee.

BACKGROUND: In recent years, decisions regarding the treatment of individual patients have increasingly been affected by economic considerations. The G-DRG system reimburses sledge endoprosthetic implantations at a much lower rate than surface replacements and at significantly different cost weights (CW). Therefore, when only G-DRG payments are considered, TKA produces higher gains. Taking only these revenues alone into consideration, however, does not provide the basis of an economically sound decision-making process. The target of this research was to present a comparison between variable costs of the two procedures. METHODS: The mean cost and performance data of 28 Endo-Modell (Link company) sledge implantations (UKS) and of 85 NexGen CR surface replacement total knee arthroplasties (TKA; Zimmer company) were compared in 2007. RESULTS: From the perspective of the hospital, UKS treatment is of greater economic advantage when the medical indication is given. In preferring UKS marginal contribution can be improved, and although the relative weighting is comparatively low, the costs are significantly lower than in a comparative analysis of TKA. Based on the length of stay required for each procedure the average daily CW for UKS can be calculated as 0.1728, while being 0.1955 for TKA. The earlier release of the first patient results in another patient being admitted 1.5 days earlier and thus an increase in case mix. Meanwhile, the case-mix index and the costs of care per case decrease ceteris paribus. CONCLUSION: Assuming the correct medical indication, the hospital seeking to maximize its marginal contribution would be wise to select sledge endoprosthesis implantation. Considering the economic perspective of gains and costs, the assumption that TKA is advantageous could not be confirmed in the present study.

Reconstruction of large defects in vertebral osteomyelitis with expandable titanium cages.

The purpose of this study was to investigate the outcome of expandable titanium cage implantation in large defects caused by acute vertebral osteomyelitis. Twenty-five patients with acute single or multilevel spondylodiscitis were treated after radical débridement and posterior instrumentation with an anterior expandable titanium cage and bone grafting. Clinical, laboratory and radiological follow-up continued for 36 months. Within the postoperative course there was no recurrence of spinal infection. The final radiological examination showed successful fusion in all cases without implant loosening or failure. At the final follow-up after 36 months the Oswestry Disability Index was 23 +/- 14 and the pain visual analogue scale 2.1 +/- 1.7. This study reveals healing and improved function after expandable titanium cage implantation in all patients. Prerequisites for optimal healing include radical débridement, provision of stability for weight-bearing, adequate bone grafting and correction of deformity using rigid implants.

Loads on a telemeterized vertebral body replacement measured in three patients within the first postoperative month.

BACKGROUND: Little is known about the loads acting on a vertebral body replacement within the first month postoperatively. Among other things, such data are required for choosing the optimal rehabilitation program for a patient and for evaluating the efficacy of aids like crutches and braces. METHODS: Telemeterized vertebral body replacements were implanted into three patients, replacing parts of their fractured vertebral body L1. Six load components were measured for several exercises in upright and lying positions within the first postoperative month. The fractured vertebra was additionally stabilized with an internal spinal fixation device. FINDINGS: The highest force component acted in the direction defined by a line connecting the centres of the adjacent vertebral bodies. The resultant force was always less than 100 N in a lying position. Standing and sitting caused forces between about 150 and 450 N. Support with the arms or hands reduced the force considerably. Flexion of the upper body caused resultant forces higher than 420 N in all three patients. Elevation of both arms in the sagittal plane to about 90 degrees also led to high resultant forces, especially when carrying an additional weight in the hands or when working against the resistance of a physiotherapist. In the latter case, forces higher than 700 N were measured. The force direction was close to the axial direction of the treated spinal segment in upright body positions and varied only slightly for most exercises. The highest resultant bending and torsional moments measured were less than 4 Nm. For most exercises the resultant moment was below 2 Nm. INTERPRETATION: High loads act on a vertebral body replacement during several exercises already in the first month postoperatively. These activities should be avoided, especially in patients with osteoporotic vertebrae in order to prevent implant subsidence. Using e.g. a wheeled invalid walker or supporting the upper body by hands when sitting was found to reduce implant loads.

Successful treatment of spondylodiscitis using titanium cages: a 3-year follow-up of 22 consecutive patients.

BACKGROUND AND PURPOSE: The use of metal implants in large defects caused by spinal infection to support the anterior column is controversial, and relatively few results have been published to date. Despite the fact that there is bacterial adhesion to metal implants, the strong immunity of the highly vascularized spine because of rich muscle covering is unique. This possibly allows the use of metal implants, which have the advantage of high stability and reduced loss of correction. This is a retrospective study of patients with spondylodiscitis treated with metal implants. PATIENTS AND METHODS: We retrospectively analyzed the outcome in 22 consecutive patients (mean age 69 (43-82) years, 15 men) with spondylodiscitis (20 lumbar and 12 thoracic discs) who had received an anterior titanium cage implantation. In 13 cases, the pathogen could be identified. Antibiotic treatment was continued for at least 12 weeks postoperatively. RESULTS: The mean follow-up was 36 (32-47) months. Healing of inflammation was confirmed by clinical, radiographic, and laboratory parameters. The mean VAS improved from 9.1 (6-10) preoperatively to 2.6 (0-6) at the final follow-up, and the mean Oswestry disability index was 17 (0-76) at the final follow-up. INTERPRETATION: Our findings highlight the high healing rate and stability when titanium implants are used. Prerequisites are a radical debridement, correction of deformity, and additional bony fusion by bone grafting. The increased stability, with facilitated patient mobilization, and the relatively little loss of correction using anterior and posterior implants are of considerable advantage in the treatment of the patients with multiple co-morbidities.

Postoperative multisegmental lumbar discitis treated by staged ventrodorsoventral intervention.

BACKGROUND: Postoperative spinal infections are relatively rare. They can become life-threatening. CASE REPORT: A 56-year-old man developed multisegmental spinal infection with methicillin-resistant Staphylococcus aureus after discectomy at L3/4. A staged ventrodorsoventral intervention was needed for radical debridement and stabilization. After femoral head necrosis developed as a result of the infection, a Girdlestone hip was maintained until the joint was aseptic and a hip prosthesis could be implanted. Two years postoperatively, the patient remained free of infection recurrence. CONCLUSION: Radical debridement and a tightly controlled antibiotic regimen are necessary for the management of postoperative spinal infections. This should include staged interventions until recovery from infection is possible. Early intervention can prevent systemic sepsis caused by widespread bacterial dissemination.

Value of preoperative ultrasound marking of calcium deposits in patients who require surgical treatment of calcific tendinitis of the shoulder.

PURPOSE: The objective of our study was to evaluate whether preoperative ultrasound-guided marking of calcium deposits has a positive effect on the efficiency and speed of localization of calcium deposits during surgery, and whether this technique is a factor that increases the probability of good clinical results. METHODS: Twenty-four patients who required surgery for calcific tendinitis in the years 2001 and 2002 were divided into 2 groups of 12 patients by week. Before undergoing surgery, those in group 1 (weeks 1, 3, 5, etc.) were given a standard ultrasound examination, along with preoperative ultrasound-guided marking (pre-USM) of calcium deposits, whereas group 2 (weeks 2, 4, 6, etc.) received the standard ultrasound examination without pre-USM. In both groups, arthroscopic removal of calcium deposits was carried out and the postoperative treatment plan was identical. The clinical result was evaluated by the Constant-Murley score. RESULTS: At the 6-week and 2-year follow-up visits, the clinical result was significantly better (P < .05) in the pre-USM group than in the unmarked group (Constant score of 76 v 70 points and 80 v 74 points, respectively). After 12 weeks, the clinical outcomes of both groups showed an approaching significance, with better results seen in the pre-USM group (79 v 74 points; P = .052). The time required for intraoperative localization of calcium deposits was 16 versus 22 minutes. The difference showed an approaching significance (P = .057). Removal of calcium was possible in 12 versus 10 cases; complete removal was possible in 8 versus 6 cases, respectively. However, none of these variables had a statistically significant influence on our results. CONCLUSIONS: Preoperative ultrasound-guided marking of calcific deposits is a procedure that statistically significantly improves the clinical results of arthroscopic surgery as seen at 6 weeks and 2 years; statistical significance of .052 was approached only at 12 weeks, as we have shown here for calcifying tendinitis of the shoulder joint. LEVEL OF EVIDENCE: Level III, development of diagnostic criteria with nonconsecutive patients.

Fracture care using percutaneously applied titanium mesh cages (OsseoFix®) for unstable osteoporotic thoracolumbar burst fractures is able to reduce cement-associated complications--results after 12 months.

BACKGROUND: Despite the known demographic shift with expected doubled rate of vertebral body fractures by the year 2050, a standardized treatment concept for traumatic and osteoporotic incomplete burst fracture of the truncal spine does not exist. This study aims to determine whether minimally invasive fracture care for incomplete osteoporotic thoracolumbar burst fractures using intravertebral expandable titanium mesh cages is a suitable procedure and may provide improved safety in terms of cement-associated complications in comparison to kyphoplasty procedure. METHODS: In 2011/2012, 15 patients (10 women, 5 men; mean age 77) with 15 incomplete osteoporotic thoracolumbar burst fractures (T10 to L4) were stabilized using intravertebral expandable titanium mesh cages (OsseoFix®) as part of a prospective study. X-ray, MRI and bone density measurements (DXA) were performed preinterventionally. The clinical and radiological results were evaluated preoperatively, postoperatively and after 12 months according to the visual analogue scale (VAS), the Oswestry Disability Index (ODI), X-ray (Beck Index, Cobb angle) and CT analyses. Wilcoxon rank sum test, sign test and Fischer's exact test were used for statistical evaluation. RESULTS: A significant reduction in pain intensity (VAS) from preoperative 8.0 to 1.6 after 12 months and significant improvement in activity level (ODI) from preoperative 79.0 to 30.5 % after 12 months were revealed. Radiologically, the mean kyphotic angle according to Cobb showed significant improvements from preoperative 9.1° to 8.0° after 12 months. A vertebral body subsidence was revealed in only one case (6.7 %). No changes in the position of the posterior wall were revealed. No cement leakage or perioperative complications were seen. CONCLUSION: As a safe and effective procedure, the use of intravertebral expandable titanium mesh cages presents a valuable alternative to usual intravertebral stabilization procedures for incomplete osteoporotic burst fractures and bears the potential to reduce cement-associated complications. TRIAL REGISTRATION: German Clinical Trials Register (DKRS) DRKS00008833 .

Ultrasonographic imaging of fractures of the clavicle in newborn infants.

Fractures of the clavicle in the neonate are usually diagnosed by clinical examination and confirmed by plain radiography. Exposure of newborn infants to irradiation should be avoided if possible. Following the clinical examination of 2978 neonates, 15 had suspected fractures of the clavicle. All were confirmed by ultrasound. In combination with clinical examination, ultrasound is a satisfactory alternative to radiological assessment for the diagnosis of fractures of the clavicle in newborn children.

Permanent thoracic myelopathy resulting from herniation of a calcified intervertebral disc in a child.

This retrospective study was made to illustrate the rare occurrence of neurologic deficits resulting from intervertebral disc calcification (IDC) in a child. Most authors agree that juvenile IDC is usually a benign, self-limiting disease with excellent prognosis. The symptoms subside spontaneously in 95% of patients. Conservative treatment is therefore usually sufficient. Reviewing the English-speaking literature, only two further cases of operated juvenile IDC with myelopathy have been published. In the current report, we describe a case of permanent thoracic myelopathy resulting from juvenile IDC treated by urgent decompressive thoracic laminectomy. At the 3-year follow-up examination, the patient had not recovered fully. Persisting deficits in motor and sensory function were observed.

Single-stage epidural catheter lavage with posterior spondylodesis in lumbar pyogenic spondylodiscitis with multilevel epidural abscess formation.

BACKGROUND: Despite significant advances in the conservative management of pyogenic spondylodiscitis, consecutive instability, deformity, and/or neurologic compromise demands a prompt surgical intervention. However, in rare cases involving additional multilevel epidural abscess formation, the appropriate surgical strategy remains controversial. In this retrospective cohort analyses, we evaluated the efficacy of a single-stage posterior approach with the addition of a one-time multilevel epidural lavage via the surgically exposed interlaminar fenestration of the infected segment. METHODS: From January 2009 through December 2010, 73 patients presenting pyogenic spondylodiscitis with instability of the lumbar spine were admitted. In all cases, the surgical strategy included a radical resection of the affected intervertebral disc and stabilization by intervertebral fusion using a titanium cage with autologous bone grafting in a level-dependent posterior approach with additional pedicle screw-and-rod instrumentation. In cases where multilevel abscess formation was evident, the standard surgical procedure was complemented by drainage and irrigation of the abscess from posterior by carefully advancing a soft infant feeding tube via the surgically exposed epidural space under fluoroscopic guidance. All patients received complementary oral antibiotic therapy for 12 weeks and were followed-up for a minimum of 12 months postoperatively. RESULTS: Ten patients (three male and seven female patients; mean age: 64.9 ± 10.9 years) presented with an additional lumbar epidural abscess extending beyond three levels proximal or distal to the infected disc. In all 10 patients the laboratory-chemical inflammatory parameters (leukocyte count, C-reactive protein) remained within the physiologic range after completing antibiotic therapy throughout the 1-year follow-up period. The plain radiographs and magnetic resonance imaging demonstrated solid fusion and the complete remission of the initial abscess formation after 3 to 6 months with no recurrence of infection, respectively. CONCLUSION: The onetime epidural lavage presented in this small patient cohort proved to be an effective surgical adjunct with minimal exposure-related morbidity. We believe that the possibility of early mobilization and the patient's increased rehabilitation potential reduce the risk of nosocomial complications that often coincide with this multimorbid high-risk group of patients.

Percutaneous Stabilization System Osseofix® for Treatment of Osteoporotic Vertebral Compression Fractures - Clinical and Radiological Results after 12 Months.

STUDY DESIGN: A prospective consecutive cohort study (follow-up study). OBJECTIVE: Our study investigated whether implantation of an expandable titanium mesh cage (Osseofix®) is a successful and safe minimally invasive therapy for osteoporotic vertebral compression fractures (VCF). Our experiences, clinical and radiological findings after 12 months follow-up are presented. Kypho- and vertebroplasty are well-established minimally invasive procedures for the treatment of osteoporotic VCF. The main complications associated with both procedures are uncontrolled bone cement leakage. Therefore a suitable alternative has been investigated. METHODS: During June 2010 to May 2011 24 patients were included with 32 osteoporotic VCF (T6 to L4). All of them were stabilized with the Osseofix® system. Preinterventionally we performed X-ray, MRI, and bone density measurements (DXA). Clinical and radiological results were evaluated preop., postop. and after 12 months postop. based on the Oswestry Disability Index (ODI) and the Visual Analogue Scale (VAS), X-ray (Beck Index, Cobb-angle) and CT. RESULTS: There was a significant improvement in the mean ODI (70,6% to 30,1%) as well as a significant reduction in pain intensity (VAS) (7,7 to 1,4) after 12 month. The mean kyphotic angle according to Cobb showed significant improvements (11,7° to 10,4°) after 12 months. Postinterventional imaging showed only one case of loss of height in a stabilized vertebral body (3.1%). We saw no changes in posterior vertebral wall or adjacent fractures. Except for one pronounced postoperative hematoma we saw no surgical complications including no cement leakage. CONCLUSIONS: Stabilization of symptomatic osteoporotic VCF with Osseofix® system is a safe and effective procedure, even in fractures with posterior wall involvement. The clinical mid-term results are good at a very low complication rate. The Osseofix® system is an interesting alternative to the established procedures of cement augmentation.

Disc volume reduction with percutaneous nucleoplasty in an animal model.

STUDY DESIGN: We assessed volume following nucleoplasty disc decompression in lower lumbar spines from cadaveric pigs using 7.1Tesla magnetic resonance imaging (MRI). PURPOSE: To investigate coblation-induced volume reductions as a possible mechanism underlying nucleoplasty. METHODS: We assessed volume following nucleoplastic disc decompression in pig spines using 7.1-Tesla MRI. Volumetry was performed in lumbar discs of 21 postmortem pigs. A preoperative image data set was obtained, volume was determined, and either disc decompression or placebo therapy was performed in a randomized manner. Group 1 (nucleoplasty group) was treated according to the usual nucleoplasty protocol with coblation current applied to 6 channels for 10 seconds each in an application field of 360°; in group 2 (placebo group) the same procedure was performed but without coblation current. After the procedure, a second data set was generated and volumes calculated and matched with the preoperative measurements in a blinded manner. To analyze the effectiveness of nucleoplasty, volumes between treatment and placebo groups were compared. RESULTS: The average preoperative nucleus volume was 0.994 ml (SD: 0.298 ml). In the nucleoplasty group (n = 21) volume was reduced by an average of 0.087 ml (SD: 0.110 ml) or 7.14%. In the placebo group (n = 21) volume was increased by an average of 0.075 ml (SD: 0.075 ml) or 8.94%. The average nucleoplasty-induced volume reduction was 0.162 ml (SD: 0.124 ml) or 16.08%. Volume reduction in lumbar discs was significant in favor of the nucleoplasty group (p<0.0001). CONCLUSIONS: Our study demonstrates that nucleoplasty has a volume-reducing effect on the lumbar nucleus pulposus in an animal model. Furthermore, we show the volume reduction to be a coblation effect of nucleoplasty in porcine discs.

Percutaneous disc decompression with nucleoplasty-volumetry of the nucleus pulposus using ultrahigh-field MRI.

PURPOSE: To evaluate changes in nucleus pulposus volume as a potential parameter for the effects of disc decompression. METHODS: Fifty-two discs (T8 to L1) were extracted from 26 pigs and separated into thoracic (T8 to T11) and thoracolumbar discs (T12 to L1). The discs were imaged using 7.1 Tesla ultrahigh-field magnetic resonance imaging (MRI) with acquisition of axial T2-weighted turbo spin-echo sequences for determination of baseline and postinterventional nucleus pulposus volumes. Volumes were calculated using OsiriX® (http://www.osirix-viewer.com). After randomization, one group was treated with nucleoplasty, while the placebo group was treated with an identical procedure but without coblation current. The readers analyzing the MR images were blinded to the kind of procedure performed. Baseline and postinterventional volumes were compared between the nucleoplasty and placebo group. RESULTS: Average preinterventional nucleus volume was 0.799 (SD: 0.212) ml. Postinterventional volume reduction in the nucleoplasty group was significant at 0.052 (SD: 0.035) ml or 6.30% (p<0.0001) (thoracic discs) and 0.082 (SD: 0.042) ml or 7.25% (p = 0.0078) (thoracolumbar discs). Nucleoplasty achieved volume reductions of 0.114 (SD: 0.054) ml or 14.72% (thoracic) and 0.093 (SD: 0.081) ml or 11.61% (thoracolumbar) compared with the placebo group. CONCLUSIONS: Nucleoplasty significantly reduces thoracic and thoracolumbar nucleus pulposus volumes in porcine discs.

Analysis of IL-17(+) cells in facet joints of patients with spondyloarthritis suggests that the innate immune pathway might be of greater relevance than the Th17-mediated adaptive immune response.

INTRODUCTION: In this study, we analysed the number of IL-17(+) cells in facet joints, in the peripheral blood (PB) and synovial fluid (SF) of spondyloarthritis (SpA) patients and compared these results with those of patients with other rheumatic diseases and controls. METHODS: Immunohistochemical analysis of IL-17(+) cells was performed in facet joints of 33 ankylosing spondylitis (AS) patients and compared with data from 20 osteoarthritis (OA) patients. The frequency of IL-17(+)CD4(+) T cells in PB and SF of SpA patients (PB n = 30, SF n = 11), rheumatoid arthritis (RA) patients (PB n = 14, SF n = 7), OA patients (PB n = 10) and healthy controls (PB n = 12) was analysed after stimulation with Staphylococcus aureus Enterotoxin B and phorbol 12-myristate 13-acetate/ionomycin and quantified by flow cytometry. RESULTS: In AS facet joints, the frequency of IL-17-secreting cells was significantly higher than in samples obtained from OA patients (P < 0.001), with a slight predominance of IL-17(+) cells among the mononuclear cells (61.5% ± 14.9%) compared to cells with polysegmental nuclei. Immunofluorescence microscopy revealed that the majority of IL-17(+) cells were myeloperoxidase-positive (35.84 ± 13.06/high-power field (HPF) and CD15(+) neutrophils (24.25 ± 10.36/HPF), while CD3(+) T cells (0.51 ± 0.49/HPF) and AA-1(+) mast cells (2.28 ± 1.96/HPF) were less often IL-17-positive. The frequency of IL-17(+)CD4(+) T cells in the PB and SF of SpA patients did not differ significantly compared to RA patients, OA patients or healthy controls. CONCLUSIONS: Our data suggest an important role for IL-17 in the inflammatory processes in AS. However, the innate immune pathway might be of greater relevance than the Th17-mediated adaptive immune response.

Immunohistochemical analysis of osteoblasts in zygapophyseal joints of patients with ankylosing spondylitis reveal repair mechanisms similar to osteoarthritis.

OBJECTIVE: New bone formation of the spine is a typical feature of ankylosing spondylitis (AS). It is unknown whether new bone formation is part of a physiological repair process or a unique pathological entity of the disease. METHODS: We analyzed zygapophyseal joints from patients with AS and osteoarthritis (OA) undergoing spinal surgery for rigid hyperkyphosis (AS) or radiculopathy caused by severe OA. In 17 patients with AS, 11 with OA, and 5 controls we performed immunohistochemical analysis of osteoprotegerin (OPG), nuclear factor-kappaB ligand (RANKL), and osteocalcin (OC) expression in osteoblasts and determined the trabecular thickness in AS and OA patients and controls. Osteoclasts were detected by tartrate-resistant alkaline phosphatase (TRAP) staining. RESULTS: Trabecular thickness was significantly lower in patients with AS compared to OA (p = 0.01). The absolute number of CD56+ osteoblasts (p < 0.001) and OC+ (p = 0.002), OPG+ (p = 0.003), and RANKL+ osteoblasts (p = 0.03) in AS patients was also significantly lower than in OA patients. The percentages of OC+, OPG+, and RANKL+ osteoblasts did not differ between AS and OA (p > 0.05 in all cases). In controls, the percentages of OPG+ (p = 0.013) and OC+ (p = 0.034) but not RANKL+ (p > 0.05) osteoblasts were significantly lower compared to AS patients. The frequency of TRAP+ osteoclasts in AS patients was significantly lower compared to OA (p < 0.001), but higher compared to controls. CONCLUSION: Immunohistochemical analysis of zygapophyseal joints suggested that osteoblast activity is similar in AS and OA, indicating that new bone formation is possibly a physiological function of repair in both diseases.

Loads on a telemeterized vertebral body replacement measured in two patients.

STUDY DESIGN: The loads acting on a vertebral body replacement (VBR) were measured in vivo. OBJECTIVE: To measure the implant loads for different activities within the first 6 months after surgery. SUMMARY OF BACKGROUND DATA: Mathematical models exist for predicting spinal loads for various activities. The intradiscal pressure has been measured in vivo for many activities. Loads on internal spinal fixation devices have been measured in 10 patients. However, only little information exists regarding the loads acting on a VBR. METHODS: Telemeterized VBRs were implanted into 2 patients with a fractured L1 vertebral body. The implant allows the in vivo measurement of 3 force and 3 moment components acting on the implant. For several activities, implant loads were measured in the first 6 months after surgery. RESULTS: One month after surgery, the resultant force during standing was about 270 N in 1 patient and 300 N in the other. When the patients were lying in relaxed positions, resultant forces were less than 30% of the values during standing. In one patient, implant loads were slightly lower during sitting than during standing whereas in the other patient higher loads were measured during sitting. In both patients, flexion of the upper body and walking upstairs caused implant loads, which were more than twice as high as those during standing. Force direction varied only slightly for forces higher than 100 N. CONCLUSION: High forces may act on a VBR especially in the first postoperative month. Flexion of the upper body and going upstairs cause high implant loads and should be avoided in the first few months after stabilizing the spine.

Complications and safety aspects of kyphoplasty for osteoporotic vertebral fractures: a prospective follow-up study in 102 consecutive patients.

BACKGROUND: Kyphoplasty represents an established minimal-invasive method for correction and augmentation of osteoporotic vertebral fractures. Reliable data on perioperative and postoperative complications are lacking in the literature. The present study was designed to evaluate the incidence and patterns of perioperative complications in order to determine the safety of this procedure for patients undergoing kyphoplasty. PATIENTS AND METHODS: We prospectively enrolled 102 consecutive patients (82 women and 20 men; mean age 69) with 135 operatively treated fractured vertebrae who underwent a kyphoplasty between January 2004 to June 2006. Clinical and radiological follow-up was performed for up 6 months after surgery. RESULTS: Preoperative pain levels, as determined by the visual analogous scale (VAS) were 7.5 +/- 1.3. Postoperative pain levels were significantly reduced at day 1 after surgery (VAS 2.3 +/- 2.2) and at 6-month follow-up (VAS 1.4 +/- 0.9). Fresh vertebral fractures at adjacent levels were detected radiographically in 8 patients within 6 months. Two patients had a loss of reduction with subsequent sintering of the operated vertebrae and secondary spinal stenosis. Accidental cement extravasation was detected in 7 patients in the intraoperative radiographs. One patient developed a postoperative infected spondylitis at the operated level, which was treated by anterior corporectomy and 360 degrees fusion. Another patient developed a superficial wound infection which required surgical revision. Postoperative bleeding resulting in a subcutaneous haematoma evacuation was seen in one patient. CONCLUSION: The data from the present study imply that percutaneous kyphoplasty can be associated with severe intra- and postoperative complications. This minimal-invasive surgical procedure should therefore be performed exclusively by spine surgeons who have the capability of managing perioperative complications.

Pitfalls and complications in the treatment of cervical spine fractures in patients with ankylosing spondylitis.

Patients with ankylosing spondylitis are at significant risk for sustaining cervical spine injuries following trauma predisposed by kyphosis, stiffness and osteoporotic bone quality of the spine. The risk of sustaining neurological deficits in this patient population is higher than average. The present review article provides an outline on the specific injury patterns in the cervical spine, diagnostic algorithms and specific treatment modalities dictated by the underlying disease in patients with ankylosing spondylitis. An emphasis is placed on the risks and complication patterns in the treatment of these rare, but challenging injuries.

Temporary vertical transarticular-pin fixation of unstable ankle fractures with critical soft tissue conditions.

Unstable ankle fractures are demanding injuries to treat. Open reduction and internal fixation are accepted as standard care, however, in patients with severe soft tissue damage or serious medical conditions, this approach may not always be advisable. Closed reduction with temporary fixation using vertical transarticular pins is one method to maintain joint alignment until an open technique is possible. Fourteen patients (median age: 59.5 years) with unstable ankle fractures, including three type-2 open fractures, were included in the study. Open reduction and fixation was delayed because of severe soft tissue damage, and a temporary transarticular pin fixation using two Kirschner wires was performed. After a median of 8.4 days, an open reduction and internal fixation was carried out in all patients. No complications related to the temporary arthrodesis were observed during the acute phase, and follow-up at 24 months revealed no damage to the articular surface attributable to the pin insertion. The median Olerud-score was 33.43, but three patients showed signs of early post-traumatic arthritis which we felt were due to the initial fracture. We conclude that closed reduction and temporary fixation using vertical transarticular pins of unstable ankle fractures is a safe method of maintaining joint alignment until a definitive open approach is feasible.

Tight hamstring syndrome and extra- or intraspinal diseases in childhood: a multicenter study.

Tight hamstrings syndrome (THS) has been attributed to a number of disorders. Most authors argue that tight hamstring syndrome is determined in the majority of cases by a protruding or slipped vertebral disc. The term "disc related tight hamstring syndrome" is usually used to describe the condition. However, tight hamstring syndrome in childhood can also be an initial symptom of a usually severe disease. We reviewed retrospectively 102 children who had presented to our clinics with tight hamstring syndrome in the past 22 years (between 1980 and 2001). To our knowledge, this study includes the largest number of patients with tight hamstring syndrome analysed so far. Seventy four children (73%) suffered from severe underlying diseases. In more than one-third of all THS cases (38 of 102 cases; 37%), we observed intra- or extraspinal tumorous alterations. In 15% of the cases (15 of 102), osteomyelitis or spondylodiscitis was diagnosed. Only in 27% of the cases (28 of 102), disc protrusion, one of the commonly known underlying diagnoses (14 cases), or higher-grade spondylolisthesis/spondyloptosis (14 cases) were the inciters. Our results suggest that tight hamstring syndrome in childhood can be an initial symptom of an associated, usually severe disease. We conclude that therefore further diagnostic evaluation is required when tight hamstring syndrome is observed. A rapid initiation of an adequate primary therapy could be indicated.