Can we predict favourable quality of life after surgically treated vertebral osteomyelitis? Analysis of a prospective study.

PURPOSE: Vertebral osteomyelitis (VO) is a severe clinical entity associated with significant morbidity and mortality. Several studies have showed that successful treatment of VO patients leads to significantly improved quality of life (QoL). Nevertheless, QoL levels of these patients remained below those of the general population. There are rarely studies focusing on predicting factors for favourable QoL after surgically treated VO. The aim of this study was to identify factors influencing positively the QoL of patients undergoing surgery for VO. METHODS: We conducted a prospective monocentric study including surgically treated VO patients from 2008 to 2016. Data were collected before (T0) and 1 year (T1) after surgery. Primary outcome was favourable QoL defined as back pain with disability restricting normal life activity with a cutoff value ≥ 12 on Oswestry Disability Index (ODI). ETHICS: Ethical approval was given by the Faculty of Medicine at the University of Cologne (09-182). RESULTS: A total of 119 patients surviving 1 year after surgically treated VO were analysed. Favourable QoL was achieved in 35/119 patients. On multivariate analysis, younger age (hazard ratio = HR: 0.95; 95% CI 0.91-0.99; p = 0.022), lower albumin (HR: 0.9; 0.83-0.98; p = 0.019) an ASA score ≤ 2 (HR:4.24; 95%CI 1.42-12.68; p = 0.010), and a lower preoperative leg pain on the VAS (HR: 0.86; 95% CI 0.76-0.97; p = 0.018) were identified as independent risk factors for favourable QoL. Interestingly, the absence of neurological deficits was not predictive for a favourable outcome by means of QoL. CONCLUSION: One-third of surgically treated VO patients (29%) in our cohort achieved favourable QoL by means of ODI. Our findings can facilitate an estimation of the prognosis when informing the patient before surgery, and underscore that spine disability questionnaires, such as ODI, measuring QoL, are mandatory to evaluate comprehensively the outcome of this entity.

Diagnostic accuracy of wrist MRI in comparison to wrist arthroscopy regarding TFCC lesions in clinical practice.

INTRODUCTION: The purpose of this study was to arthroscopically verify MRI diagnostic accuracy for triangular fibrocartilage complex (TFCC) lesions in a regular clinical environment. METHODS: A total of 859 patients' data with both preoperative MRI of the wrist and additional wrist arthroscopy were retrospectively reviewed. Two board-certified hand surgeons and one orthopaedic surgeon executed wrist arthroscopy, whereas more than 100 radiologists examined the MRI of the wrist. The accordance of TFCC lesion classification using MRI in comparison to wrist arthroscopy and diagnostic precision of the former depending on technical details were evaluated. RESULTS: Diagnostic accuracy of MRI for TFCC lesions is poor in comparison to wrist arthroscopy as the reference standard. Technical specifications for MRI of the wrist are heterogeneous among the radiologists. These parameters have not improved accuracy of TFCC evaluation at large. CONCLUSION: The accuracy of MRI in a regular clinical environment still remains inferior to wrist arthroscopy for detection of TFCC lesions. Development of a standard MRI protocol may be implemented on a regular basis and application of the Palmer classification for TFCC lesion should be sought.

Clinical outcome after lumbar spinal fusion surgery in degenerative spondylolisthesis: a 3-year follow-up.

INTRODUCTION: Lumbar spinal fusion surgery is a widely accepted surgical treatment in degenerative causes of lumbar spondylolisthesis. The benefit of reduction of anterior displacement and restoration of sagittal parameters is still controversially debated. Purpose of the underlying publication was to analyze the influence of radiographic sagittal parameters of the spine in aspects of changes in postoperative clinical outcome. MATERIALS AND METHODS: By prospective analysis, we included patients with low-grade degenerative lumbar spondylolisthesis (Meyerding grades I and II) with mono- or bisegmental fusion surgery with a minimum follow-up data of 3 years. For clinical outcome measures, COMI, ODI and EQ-5D were used. Spinopelvic parameters (sacral inclination, pelvic tilt, sacral slope and pelvic incidence, lumbar lordosis and lumbar index as well as anterior displacement and sagittal rotation) were measured on plain radiographs. RESULTS: We could observe a significant benefit in clinical outcome after lumbar fusion surgery in low-grade spondylolisthesis in our mid-term follow-up data including 32 patients. By surgical reduction, we could see significant restoration of anterior displacement and sagittal rotation. Interestingly, a significant correlation between restoration of both sagittal rotation and sacral inclination and clinical outcome score was observed in the 3-year follow-up. CONCLUSION: In low-grade spondylolisthesis, spinal fusion surgery is a well-established surgical procedure; however, the impact of sagittal parameters and reduction of anterior displacement remains controversial. Within our findings, restoration of sagittal parameters showed significant correlation to improvement in clinical outcome in our mid-term follow-up data.

Long-term outcome after arthroscopic debridement of Palmer type 2C central degenerative lesions of the triangular fibrocartilage complex.

PURPOSE: The purpose of this study was to report long-term objective and patient-reported outcome after arthroscopic debridement of central degenerative triangular fibrocartilage complex (TFCC) lesions. METHODS: A total of 17 patients with central degenerative TFCC (Palmer type 2C) lesions and ulnar positive variance who were treated by arthroscopic debridement were retrospectively reviewed. Mean follow-up was 8.8 years. Assessment facilitating the Modified Mayo Wrist score (MMWS), the Disabilities of the Arm, Shoulder, and Hand questionnaire (DASH score), recording of pain level and of patient satisfaction, and radiological examination were done. RESULTS: Patients reached a pain level of 1.7 VAS, MMW score of 92, and DASH score of 22. No significant differences could be detected between the operated and the contralateral extremity regarding range of motion and grip strength for all patients. No perioperative complications occurred. CONCLUSION: Arthroscopic debridement of central degenerative TFCC lesions is safe, reliable, and efficacious even for ulnar positive variance. LEVEL OF EVIDENCE: Therapeutic IV.

Viscoelastic properties of the human A2 finger pulley.

INTRODUCTION: Biomechanical evaluation of the viscoelastic properties tissue deformation, stiffness, and maximum breaking load of the human A2 pulley. We hypothesized that the A2 pulleys of index, middle, and ring fingers exhibit no difference regarding the aforementioned biomechanical parameters. METHODS: Forty-one A2 pulleys of 14 upper extremities (8 body donors) were assessed. Cyclic and load-to-failure testing were performed. The biomechanical parameters tissue deformation during cyclic and load-to-failure testing, stiffness, and maximum breaking load were determined. RESULTS: No significant differences between the fingers could be detected regarding the biomechanical parameters. A significant negative correlation could be detected between stiffness and deformation of the pulley. Significant positive correlations could be identified between stiffness and maximum breaking load and between maximum breaking load and deformation of the pulleys. CONCLUSIONS: Assessment of the viscoelastic properties of the A2 finger pulley promotes precise diagnosis of pulley lesions and will help to optimize treatment.

[Management of osseous complications in multiple myeloma]. / Management ossärer Komplikationen des Multiplen Myeloms.

Skeletal lesions caused by multiple myeloma often lead to pain, pathological fractures, spinal instability, and compression of the spinal cord and nerve roots. The choice of therapy options is made by an interdisciplinary basis with oncologists and radiotherapists on the basis of comorbidities, prognosis, localization, and number of lesions. Surgical management has a supportive role in pain relief, the prevention and treatment of pathological fractures, and the decompression of the spinal cord and nerve roots. An adequate preoperative workup is essential for planning surgical treatment, which includes magnetic resonance imaging of the spine. In the case of unstable spinal lesions, minimally invasive and open surgical procedures, as well as their combination, are available for stabilization and decompression. In impending and pathological fractures of the extremities, surgical procedures are superior to conservative therapy for pain relief, restoring stability, walking ability, and limb function. There are multiple options available, including osteosynthesis using bone cement and plates, intramedullary nails, and bone replacement with implants and tumor endoprostheses with good functional results. Permanent reconstruction of the lesions should be the goal of any surgical intervention. The indication for curative, wide resection of the tumor should be considered for solitary plasmocytomas of the bone. Adjuvant radiotherapy leads to significantly improved local tumor control and should be considered after resection and stabilization.

Home-based vibration assisted exercise as a new treatment option for scoliosis - A randomised controlled trial.

OBJECTIVES: The aim of this study was to evaluate the effect of scoliosis specific exercises (SSE) on a side-alternating whole body vibration platform (sWBV) as a home-training program in girls with adolescent idiopathic scoliosis (AIS). METHODS: 40 female AIS patients (10-17 years) wearing a brace were randomly assigned to two groups. The intervention was a six months, home-based, SSE program on a sWBV platform five times per week. Exercises included standing, sitting and kneeling. The control group received regular SSE (treatment as usual). The Cobb angle was measured at start and after six months. Onset of menarche was documented for sub-group analysis. RESULTS: The major curve in the sWBV group decreased significantly by -2.3° (SD±3.8) (95% CI -4.1 to -0.5; P=0.014) compared to the difference in the control group of 0.3° (SD±3.7) (95% CI -1.5 to 2.2; P=0.682) (P=0.035). In the sWBV group 20% (n=4) improved, 75% (n=15) stabilized and 5% (n=1) deteriorated by ≥5°. In the control group 0% (n=0) improved, 89% (n=16) stabilized and 11% (n=2) deteriorated. The clinically largest change was observed in the 'before-menarche' sub-group. CONCLUSIONS: Home-based SSE combined with sWBV for six months counteracts the progression of scoliosis in girls with AIS; the results were more obvious before the onset of the menarche.

T2-relaxation time increases in lumbar intervertebral discs after 21d head-down tilt bed-rest.

OBJECTIVES: Spaceflight back pain and intervertebral disc (IVD) herniations cause problems in astronauts. Purpose of this study was to assess changes in T2-relaxation-time through MRI measurements before and after head-down tilt bed-rest, a spaceflight analog. METHODS: 8 men participated in the bed-rest study. Subjects remained in 6° head down tilt bed-rest in two campaigns of 21 days, and received a nutritional intervention (potassium bicarbonate 90 mmol/d) in a cross-over design. MRI measurements were performed 2 days before bed-rest, as well as one and five days after getting up. Image segmentation and data analysis were conducted for the IVDs Th12/L1 to L5/S1. RESULTS: 7 subjects, average age of 27.6 (SD 3.3) years, completed the study. Results showed a significant increase in T2-time in all IVDs (p⟨0.001), more pronounced in the nucleus pulposus than in the annulus fibrosus (p⟨0.001). Oral potassium bicarbonate did not show an effect (p=0.443). Pfirrmann-grade correlated with the T2-time (p⟨0.001). CONCLUSIONS: 6° head-down tilt bed-rest leads to a T2-time increase in lumbar IVDs. Oral potassium bicarbonate supplementation does not have an effect on IVD T2-time.

Accuracy of 3D fluoro-navigated anterior transpedicular screws in the subaxial cervical spine: an experimental study on human specimens.

INTRODUCTION: Pedicle screw stabilization, the standard technique in the thoracic and lumbar spine, is increasingly used in the cervical spine. Initial studies on the use of anterior pedicle screws (ATPS) in the cervical spine have been recently published. ATPS use has theoretical advantages over posterior stabilization. We have already established a 3D-fluoroscopy navigation setup in a study of artificial bones. The aim of the current study was to evaluate the positioning quality/accuracy of ATPS introduced to human specimens. METHODS: 36 cannulated screws (3.5 mm) were implanted anteriorly into the C3-C7 segments of four spines (unfixed, frozen, cadaveric specimens) using a 3D-fluoroscopy navigation system. Placement accuracy was evaluated using a recently published classification on postoperative CT scans. Grade 1 is perfect position with pedicle wall perforation <1 mm, grade 2 is perforation <2 mm, etc., and finally grade 5 is cortical perforation of >4 mm and/or transverse foramen entry. RESULTS: 36 anterior pedicle screws were inserted into four human cervical spine specimens. Of these, seven screws were introduced to C3, five to C4 and eight each to C5, C6, and C7. Classified with the modified G&R, 21 of 36 (58.3%) were grade 1. Ten screws (27.8%) were grade 2. Grade 4 was assessed for two screws and grade 5 for three. Customary "good" positioning, combining grades 1 and 2, was thus found in 86.1%. Five screws (13.9%) did not meet this criterion (grade ≥3). CONCLUSIONS: With 86.1% of good positioning (grade 2 or better), a 3D-fluoroscopy navigation of ATPS screws into human c-spine specimens achieved a satisfying results. These are at least comparable to results presented in the literature for posteriorly introduced subaxial pedicle screws.

[Type 2 dens fracture in the elderly and therapy-linked mortality : Conservative or operative treatment]. / Typ-II-Densfrakturen des alten Menschen und therapiebedingte Mortalität : Konservative oder operative Behandlung.

BACKGROUND: Type II fractures of the odontoid process of the axis are the most common injury of the cervical spine in elderly patients. Only little evidence exists on whether elderly patients should be treated conservatively or surgically. MATERIAL AND METHODS: The mortality and survival probability of 51 patients were determined in a retrospective study. The range of motion, pain and the neck disability index were clinically investigated. RESULTS: Of the 51 patients 37 were treated surgically and 14 conservatively. The conservatively treated group showed a higher mortality (64 % vs. 32 %). Kaplan-Meier analysis revealed a median survival of the conservatively treated group of 29 months, whereby during the first 3 months of treatment this group showed a higher survival probability and afterwards the surgically treated group showed a higher survival probability. The clinical examination of 20 patients revealed limited range of motion of the cervical spine. Additionally, moderate levels of pain and complaints were recorded using the neck disability index. CONCLUSION: Fractures of the odontoid process pose a far-reaching danger for elderly patients. A balanced assessment of the general condition should be carried out at the beginning of treatment of these patients. In the early phase following trauma no differences were found with respect to survival rates but for long-term survival the operatively treated group showed advantages; however, these advantages cannot be causally attributed to the choice of therapy.

[The biomechanics of hyperextension injuries of the subaxial cervical spine]. / Biomechanik der Hyperextensionsverletzung der subaxialen Halswirbelsäule.

Hyperextension injuries of the subaxial cervical spine are potentially hazardous due to relevant destabilization. Depending on the clinical condition, neurologic or vascular damage may occur. Therefore an exact knowledge of the factors leading to destabilization is essential. In a biomechanical investigation, 10 fresh human cadaver cervical spine specimens were tested in a spine simulator. The tested segments were C4 to 7. In the first step, physiologic motion was investigated. Afterwards, the three steps of injury were dissection of the anterior longitudinal ligament, removal of the intervertebral disc/posterior longitudinal ligament, and dissection of the interspinous ligaments/ligamentum flavum. After each step, the mobility was determined. Regarding flexion and extension, an increase in motion of 8.36 % after the first step, 90.45 % after the second step, and 121.67 % after the last step was observed. Testing of lateral bending showed an increase of mobility of 7.88 %/27.48 %/33.23 %; axial rotation increased by 2.87 %/31.16 %/45.80 %. Isolated dissection of the anterior longitudinal ligament led to minor destabilization, whereas the intervertebral disc has to be seen as a major stabilizer of the cervical spine. Few finite-element studies showed comparable results. If a transfer to clinical use is undertaken, an isolated rupture of the anterior longitudinal ligament can be treated without surgical stabilization.

Safety and efficacy of denosumab in children with osteogenesis imperfect--a first prospective trial.

OBJECTIVES: Osteogenesis imperfecta (OI) is a rare hereditary disease leading to bone fragility. Denosumab as a RANK ligand antibody inhibiting osteoclast maturation has been approved for osteoporosis treatment in adults. Aim of this study was a 48-week, open-label, pilot study of the safety and efficacy of denosumab in 10 children with OI. METHODS: Ten patients (age range: 5.0-11.0 years; at least two years of prior bisphosphonate treatment) with genetically confirmed OI were studied. Denosumab was administered subcutaneously every 12 weeks with 1 mg/kg body weight. Primary endpoint was change of areal bone mineral density (aBMD) using dual energy x-ray absorptiometry of the lumbar spine after 48 weeks. Safety was assessed by bone metabolism markers and adverse event reporting. RESULTS: Mean relative change of lumbar aBMD was +19 % (95%-CI: 7-31%). Lumbar spine aBMD Z-Scores increased from -2.23±2.03 (mean±SD) to -1.27±2.37 (p=0.0006). Mobility did not change (GMFM-88 +2.72±4.62% (p=0.16); one-minute walking test +11.00±15.82 m (p=0.15). No severe side effects occurred. CONCLUSIONS: On average, there was a significant increase in lumbar spine aBMD percent change after 48 weeks of denosumab. There was no change in mobility parameters and no serious adverse events. Further trials are necessary to assess long-term side effects and efficacy.

Spinal cord injury without radiographic abnormality (SCIWORA) in adults: MRI type predicts early neurologic outcome.

OBJECTIVES: The present study aimed to analyse the clinical and neuroimaging features of a consecutive series of adult patients with spinal cord injury without radiographic abnormality (SCIWORA) receiving early magnetic resonance imaging (MRI), and to apply the recently proposed MRI classification system. METHODS: Grade of neurologic impairment at admission and discharge was reported according to the American Spinal Injury Association Impairment Scale (AIS). A detailed analysis and categorisation of the extra- and intramedullary MRI findings was performed, and the relationship between imaging type and neurological outcome was described. RESULTS: Twenty-six adult patients (17 male and 9 female) with SCIWORA were identified (mean age of 52 years). The distribution of the initial AIS grade was 8% A (n=2), 19% B (n=5), 31% C (n=8) and 42% D (n=11) at admission and 15% (n=4) C, 58% (n=15) D and 27% (n=7) E at discharge, respectively. Type I SCIWORA was found in 23% (n=6) and type II in 77% (n=20) (IIa: 0%, IIb: 25%, IIc: 75%). The mean improvement of AIS grade in patients with type I lesions was 1.5 (median 1, range 1-3) and 0.9 (median 1, range 0-3) in type II. CONCLUSION: The findings underline the prognostic role of early MRI for adult patients with SCIWORA and support the use of the recently introduced MRI classification system. LEVEL OF EVIDENCE: Prognostic study, level III.

Predictive validity of preoperative CT scans and the risk of pedicle screw loosening in spinal surgery.

INTRODUCTION: Pedicle screw fixation is the standard technique for the stabilization of the spine, a clinically relevant complication of which is screw loosening. This retrospective study investigates whether preoperative CT scanning can offer a predictor of screw loosening. METHODS: CT-scan attenuation in 365 patients was evaluated to determine the mean bone density of each vertebral body. Screw loosening or dislocation was determined in CT scans postoperatively using the standard radiological criteria. RESULTS: Forty-five of 365 patients (12.3 %; 24 male, 21 female) suffered postoperative screw loosening (62 of 2038 screws) over a mean follow-up time of 50.8 months. Revision surgeries were necessary in 23 patients (6.3 %). The correlation between decreasing mean CT attenuation in Hounsfield Units (HU) and increasing patient age was significant (p < 0.001). Mean bone density was 116.3 (SD 53.5) HU in cases with screw loosening and 132.7 (SD 41.3) HU in cases in which screws remained fixed. The difference was statistically significant (p = 0.003). CONCLUSION: The determination of bone density with preoperative CT scanning can predict the risk of screw loosening and inform the decision to use cement augmentation to reduce the incidence of screw loosening.

[Conservative treatment of nonspecific, chronic low back pain : Evidence of the efficacy - a systematic literature review]. / Konservative Therapie beim unspezifischen, chronischen Kreuzschmerz : Evidenz der Wirksamkeit - eine systematische Literaturanalyse.

OBJECTIVES: Non-specific chronic low back pain (NSCLBP): Which conservative therapy shows an evident effectiveness - A review of the current literature. MATERIALS AND METHODS: Our results are based on literature reviews of current randomised control studies, reviews and meta-analysis drawn from the Cochrane Library and Medline-Database between the years 2004 until 2015. German and English Studies were included. We focused on different conservative Treatments of NSCLBP, which are listed at, the NVL-Guidelines. Based on the given evidence we evaluated their effectiveness. RESULTS: As part of the review we identified 4657 Publications, 85 were included in this study. Therapeutic options such as bed rest, TENS, Massage, Spine Supports, Back Schools and Antidepressants showed no evident effectiveness. Injections, NSAR analgesic therapy, Thermotherapy and Opioid analgesic therapy indicated a short-time effectiveness. A long term success (> 6 weeks) however, can not be shown. Only the Movement therapy can, in the summation of the included studies, postulate an evident (Evidence Level I) long-term effect treating NSCLBP. Only a few therapy options indicate a significant evident effectiveness for treating NSCLBP conservatively. At short notice methods such as injection therapy, thermo-therapy and analgesic therapies with NSAR and/or opioids help coping the acute phase. In the long term only movement therapy seems to provide an evident effectiveness. In the case of therapy-refractory NSCLBP a multimodal therapy should be considered.

[Should we use hip-ankle radiographs to assess the coronal alignment after total knee arthroplasty?]. / Ist die postoperative Ganzbeinaufnahme nach Knie-TEP-Implantation notwendig?

BACKGROUND: There is no consensus on whether hip-ankle radiographs or rather standardized a­p knee-radiographs should be used to assess implant position and coronal alignment after total knee arthroplasty (TKA). This study investigates whether implant position and alignment after TKA can reproducibly be assessed using a­p knee-radiographs rather than hip-ankle radiographs. MATERIALS AND METHODS: This study was performed on 100 weight-bearing hip-ankle radiographs after conventional primary TKA. The true mechanical and anatomical femorotibial angle as well as coronal implant position was assessed on hip-ankle radiographs. The radiographs were then cropped to 80, 60 and 40 % of the leg-length and tibial coronal implant position, and the anatomical axis and a surrogate mechanical axis were obtained. The difference in the alignment parameters between the hip-ankle radiographs were statistically compared with the cropped radiographs and the inter-observer correlation coefficient (ICC) was calculated. RESULTS: The ICC for measurement of the mechanical femorotibial angle was higher in hip-ankle radiographs (0.95) when compared with a radiograph cropped to 40 % (0.61). There was a significant difference in the mechanical femorotibial angle between hip-ankle radiographs and any cropped radiograph. However, there were no significant differences in coronal implant position and the anatomical femorotibial angle between hip-ankle radiographs and any cropped radiograph. CONCLUSIONS: We conclude that standard a­p knee-radiographs are insufficient to assess the mechanical alignment following TKA. However, standard a­p knee-radiographs are appropriate to assess the implant position when referenced against the anatomical axes. Weight-bearing hip-ankle radiographs should be questioned as a routine after TKA.

Hypervascular cervical spine metastases: embolization by direct injection of Onyx-18.

PURPOSE: Spinal metastases are common in patients with cancer. Following lung and liver, spine is the most common site for cancers to metastasize. Many of them are hypervascularized. These cases are a particular challenge for the surgeon and represent a significant danger of massive blood loss during surgery. Hypervascularized metastases of the cervical spine also include the risk of postoperative bleeding with severe neurological impairment. We report a case of a 67-year-old women with breast cancer (BC) metastasis within the vertebral bodies of C3 and C4 with nearly complete bony destruction of the ventral column and intraspinal tumor masses compressing the spinal cord at level C3 and C4. The hypervascularized tumor was supplied by multiple minor vessels from both vertebral arteries, too small to be coiled individually. Due to an allergy to aspirin, intravascular stenting of the vertebral arteries was not an option. We decided to perform a preoperative direct injection of onyx-18 for embolization of the tumor. CONCLUSION: Presurgical direct injection of Onyx-18 for treating hypervascular spinal metastases of breast cancer seems to be an effective and safe technique and reduces intraoperative bleeding to a minimum.

The accuracy of 3D fluoroscopy-navigated screw insertion in the upper and subaxial cervical spine.

PURPOSE: Due to better primary stability and repositioning options, pedicle screws are increasingly used during posterior stabilization of the cervical spine. However, the serious risks generally associated with the insertion of screws in the cervical spine remain. The purpose of this study is to examine the accuracy of pedicle screw insertion with the use of 3D fluoroscopy navigation systems, also accounting for various spine levels. METHODS: Data of 64 patients were collected during and after screw implantation (axial and subaxial) in the cervical spine. 207 screws were implanted from C1 to C7 and analyzed for placement accuracy according to postoperative CT scans and following the modified Gertzbein and Robbins classification. RESULTS: The accuracy of most of the inserted screws was assessed as grade 2 according to the modified Gertzbein and Robbins classification. 93.9% of the screws implanted at C1 or C2, and 78.51% of the screws implanted at levels C3-C7 showed placement accuracy grade 2 or better, indicating pedicle wall perforation of <2 mm. Overall, seven complications were observed. In three cases, the vertebral artery was affected, leading to one fatality. Surgical revision was necessary once because of Magerl screw misplacement and three times due to impaired wound healing. No radicular symptoms resulted from screw malposition. CONCLUSION: Axial and subaxial screws can be inserted with a high grade of accuracy using 3D fluoroscopy-based navigation systems. Nevertheless, while this useful innovation helps to minimize the risks of misplacement, the surgery is still a challenge, as arising complications remain severe.

Injuries in competitive boxing. A prospective study.

Boxing remains a subject of controversy and is often classified as dangerous. But the discussion is based mostly on retrospective studies. This survey was conducted as a prospective study. From October 2012 to September 2013, 44 competitive boxers were asked to report their injuries once a month. The questionnaire collected general information (training, competition) and recorded the number of bouts fought, injuries and resulting lost days. A total of 192 injuries were recorded, 133 of which resulted in interruption of training or competition. Each boxer sustained 3 injuries per year on average. The injury rate was 12.8 injuries per 1 000 h of training. Boxers fighting more than 3 bouts per year sustain more injuries (p=0.0075). The injury rate does is not a function of age (age≤19 vs. > 19a, p=0.53). Injuries to the head and the upper limbs occur most frequently. The most common injuries are soft tissue lacerations and contusions. Head injuries with neurological symptoms rarely occur (4.2%). Boxing has a high injury rate that is comparable with other contact sports, but most injuries are minor. Injury frequency is not a function of whether the boxer competes in the junior or adult category. Athletes fighting many bouts per year have a greater risk of injury.

Lumbar lordosis and sacral slope in lumbar spinal stenosis: standard values and measurement accuracy.

STUDY DESIGN: Radiological study. PURPOSE: To asses standard values, intra- and interobserver reliability and reproducibility of sacral slope (SS) and lumbar lordosis (LL) and the correlation of these parameters in patients with lumbar spinal stenosis (LSS). METHODS: Anteroposterior and lateral X-rays of the lumbar spine of 102 patients with LSS were included in this retrospective, radiologic study. Measurements of SS and LL were carried out by five examiners. Intraobserver correlation and correlation between LL and SS were calculated with Pearson's r linear correlation coefficient and intraclass correlation coefficients (ICC) were calculated for inter- and intraobserver reliability. In addition, patients were examined in subgroups with respect to previous surgery and the current therapy. RESULTS: Lumbar lordosis averaged 45.6° (range 2.5°-74.9°; SD 14.2°), intraobserver correlation was between Pearson r = 0.93 and 0.98. The measurement of SS averaged 35.3° (range 13.8°-66.9°; SD 9.6°), intraobserver correlation was between Pearson r = 0.89 and 0.96. Intraobserver reliability ranged from 0.966 to 0.992 ICC in LL measurements and 0.944-0.983 ICC in SS measurements. There was an interobserver reliability ICC of 0.944 in LL and 0.990 in SS. Correlation between LL and SS averaged r = 0.79. No statistically significant differences were observed between the analyzed subgroups. CONCLUSION: Manual measurement of LL and SS in patients with LSS on lateral radiographs is easily performed with excellent intra- and interobserver reliability. Correlation between LL and SS is very high. Differences between patients with and without previous decompression were not statistically significant.