[Conservative treatment of atraumatic femoral head necrosis]. / Konservative Therapie der atraumatischen Hüftkopfnekrose.

BACKGROUND: Femoral head necrosis is a progressive disease that can progress within a relatively short time. Therefore, an early and clear diagnosis including stage classification and treatment is necessary to prevent or delay the onset of the femoral head and joint destruction. TREATMENT: In addition to the identification of possible risk factors and treatment, the question of the available treatment options arises. The present article deals with conservative treatment options and presents the published results in the sense of the currently available evidence and against the background of the S3 guideline on atraumatic femoral head necrosis. The results of physical therapy, drug therapy (iloprost and bisphosphonates ), electrotherapy, shockwave therapy, etc. are presented. In the early stages of femoral head necrosis with low expansion, alendronate gives positive results. Iloprost is also a successful conservative treatment option in the early stages of atraumatic femoral head necrosis (ARCO I and II). In stages ARCO III and IV, Ilomedin is no longer indicated. Anticoagulants, such as enoxaparin, have demonstrated an arthroprotective effect.

[Medial Unicompartmental Knee Arthroplasty Using Patient-Specific Instrumentation - Accuracy of Preoperative Planning, Time Saving and Cost Efficiency]. / Unilaterale mediale Schlittenprothesen mit patientenspezifischer Instrumentierung - Planungsgenauigkeit, Zeitersparnis und Kosteneffektivität.

BACKGROUND: In the past few years, patient-specific instrumentation (PSI) in knee endoprosthetics has been energetically marketed. PSI can enhance the accuracy of the size and alignment of the prosthesis components. It should also be possible to reduce hospital costs and operating time. It remains unclear whether these putative advantages are achieved in medial unicompartmental knee arthroplasty (UKA). PATIENTS/MATERIAL AND METHODS: Data from 22 patients (24 knees) were analysed retrospectively. The focus was on the reliability of preoperative surgical planning - particularly with regards to the level of experience of the five surgeons involved, who were split into two groups depending on their level of experience, as defined by EndoCert®. Another focus was on the evaluation of actual surgical time and cost effectiveness using PSI. RESULTS: In order to achieve an optimal outcome, preoperative surgical planning had to be modified intraoperatively to a great extent. The femoral component had to be adjusted intraoperatively in 41.7 % of all cases, the tibial component in 58.3 % and the polyethylene insert in 87.5 %. Surgeons equipped with less experience had to change preoperative planning more often than the more experienced surgeons. Utilising PSI increased the operating time of both the less experienced and the more experienced surgeons. PSI planning and lack of surgical experience were the main predictors of increased surgical time. Instead of lowering costs, utilizing PSI increased surgical costs by nearly 1300 $ per case. This was due to increased operating time, license fees and extraordinary expenditure for MRI scans. CONCLUSION: The advertised advantages of PSI were not supported by the data analysed. On the contrary, this technology leads to additional costs, greater operating time and insufficient accuracy in preoperative planning. As not a single study has yet demonstrated better outcomes in terms of alignment and/or function with PSI than with standard instrumentation, additional data are required before PSI can be recommended for routine use in medial UKA.

In Vivo Development of Transplant Arteriosclerosis in Humanized Mice Reflects Alloantigen Recognition and Peripheral Treg Phenotype of Lung Transplant Recipients.

Experimentally, regulatory T cells inhibit rejection. In clinical transplantations, however, it is not known whether T cell regulation is the cause for, or an epiphenomenon of, long-term allograft survival. Here, we study naïve and alloantigen-primed T cell responses of clinical lung transplant recipients in humanized mice. The pericardiophrenic artery procured from human lung grafts was implanted into the aorta of NODrag-/- /IL-2rγc-/- mice reconstituted with peripheral blood mononuclear cells (PBMCs) from the respective lung recipient. Naïve or primed allogeneic PBMCs procured 21 days post-lung transplantation with or without enriching for CD4+ CD25high T cells were used. Transplant arteriosclerosis was assessed 28 days later by histology. Mice reconstituted with alloantigen-primed PBMCs showed significantly more severe transplant arteriosclerosis than did mice with naïve PBMCs (p = 0.005). Transplant arteriosclerosis was equally suppressed by enriching for autologous naïve (p = 0.012) or alloantigen-primed regulatory T cells (Tregs) (p = 0.009). Alloantigen priming in clinical lung recipients can be adoptively transferred into a humanized mouse model. Transplant arteriosclerosis elicited by naïve or alloantigen-primed PBMCs can be similarly controlled by potent autologous Tregs. Cellular therapy with expanded autologous Tregs in lung transplantation might be a promising future strategy.

S3-Guideline non-traumatic adult femoral head necrosis.

INTRODUCTION: The treatment of adult non-traumatic avascular necrosis of the femoral head (AVN; N-ANFH) within an estimated incidence of 5000-7000 cases per annum in Germany remains a challenge. Risk factors include steroids, alcohol abuse, chemotherapy and immunosuppressive medication, but a genetic predisposition has been suggested. Early diagnosis of this often bilateral disease process is essential for successful conservative or joint preserving surgical management. In this review, we present the update German consensus S3 guideline "diagnosis and management for N-ANFH" as a concise summary. MATERIALS AND METHODS: This systematic review is based on the published literature from January 1, 1970 to April 31, 2013 (German and English language). Inclusion criteria were systematic reviews, meta-analyses and relevant peer review publications. We identified a total of 3715 related publications, of which 422 were suitable according to the SIGN criteria, but only 159 fulfilled our inclusion criteria. RESULTS AND CONCLUSIONS: Clinical suspicion of N-ANFH mandates radiographic evaluation. If radiographs are normal MRI scans are recommended, which should be evaluated according to the ARCO-classification. Differential diagnoses include transient osteoporosis, bone bruise, insufficiency fracture and destructive arthropathy. Untreated, subchondral fractures commonly occur within 2 years, during which the risk for contralateral involvement is high-thereafter unlikely. Conservative management with Ilomedin and Alendronat can be tried, but other pharmacological or physical treatments are inappropriate. No specific joint preserving procedure can be recommended, but core decompression should be considered in early stages if necrosis is <30 %. In ARCO stages IIIc or IV total hip arthroplasty (THA) should be contemplated, which offers similar outcome compared to osteoarthritis. Young age is the main risk factor for higher revision rates after THA for N-ANFH.

[S3 Guideline. Part 1: Diagnosis and Differential Diagnosis of Non-Traumatic Adult Femoral Head Necrosis]. / S3-Leitline. Teil 1: Diagnostik und Differenzialdiagnostik der atraumatischen Femurkopfnekrose (aFKN) des Erwachsenen.

Non-traumatic femoral head necrosis (FHN) is primarily a disease of the middle-aged adult. Early diagnosis, at a time with lacking or minimal clinical symptoms, is mandatory to consider conservative therapy or joint preserving operations as a therapeutic option. The new German S3 guideline about diagnosis and therapy of FHN is a cooperative effort of five professional medical societies, overall headed by the Deutsche Gesellschaft für Orthopädie und Orthopädische Chirurgie (DGOOC). This review (part I/III) cites and explains the statements of the S3 guideline as agreed on the use of imaging methods for diagnosis of FHN. A diagnostic algorithm is presented. FHN clinically has to be considered in case of equivocal pain of a hip joint with a minimum of 6 weeks duration, when risk factors can be revealed, groin pain at clinical investigation, limping, pain or limitation of movement in case of load, and no obvious differential diagnoses. Is an FHN clinically suspected, primarily radiographs of the pelvis ap and a Lauenstein projection of the hip involved should be carried out. When the radiographs are normal, an MRI of the hips should follow routinely. MRI allows the diagnosis of FNH with high accuracy. Furthermore, MRI reveals the site and the size of the necrotic area involved and evaluates the integrity of the joint surface and subchondral fractures. When ARCO stage II (ARCO: Association Research Circulation Osseous) is diagnosed and MRI does not allow one to determine the joint surface with certainty, a CT of the hip joints should be performed. The S3 guideline explains and recommends the use of the ARCO classification. Although, this classification of 1993 is still largely based on radiographs, the pragmatic use of an "extended" version seems reasonable. Today, classical radiographic criteria like impression of the joint surface and subchondral fractures ("crescent sign") are better to be evaluated by MRI, in cases of subtle findings MRI is even surpassed by CT. The extent of the necrosis in the femoral head as well as the size of the surface area involved is best revealed with MRI. Additionally, in the era of cross sectional imaging a stage "0" seems obsolete. The guideline also addresses practically important considerations about the differential diagnosis of misleading MRI findings. This especially holds true for bone marrow oedema in the femoral head which may be misinterpreted. The differentiating features between FHN, transient bone marrow oedema and destructive arthropathy are discussed.

[S3 Guideline. Part 3: Non-Traumatic Avascular Necrosis in Adults - Surgical Treatment of Atraumatic Avascular Femoral Head Necrosis in Adults]. / S3-Leitlinie. Teil 3: Atraumatische Femurkopfnekrose des Erwachsenen - Operative Therapie der atraumatischen Femurkopfnekrose des Erwachsenen.

The present article describes the guidelines for the surgical treatment of atraumatic avascular necrosis (aFKN). These include joint preserving and joint replacement procedures. As part of the targeted literature, 43 publications were included and evaluated to assess the surgical treatment. According to the GRADE and SIGN criteria level of evidence (LoE), grade of recommendation (EC) and expert consensus (EK) were listed for each statement and question. The analysed studies have shown that up to ARCO stage III, joint-preserving surgery can be performed. A particular joint-preserving surgery currently cannot be recommended as preferred method. The selection of the method depends on the extent of necrosis. Core decompression performed in stage ARCO I (reversible early stage) or stage ARCO II (irreversible early stage) with medial or central necrosis with an area of less than 30 % of the femoral head shows better results than conservative therapy. In ARCO stage III with infraction of the femoral head, the core decompression can be used for a short-term pain relief. For ARCO stage IIIC or stage IV core decompression should not be performed. In these cases, the indication for implantation of a total hip replacement should be checked. Additional therapeutic procedures (e.g., osteotomies) and innovative treatment options (advanced core decompression, autologous bone marrow, bone grafting, etc.) can be discussed in the individual case. In elective hip replacement complications and revision rates have been clearly declining for decades. In the case of an underlying aFKN, however, previous joint-preserving surgery (osteotomies and grafts in particular) can complicate the implantation of a THA significantly. However, the implant life seems to be dependent on the aetiology. Higher revision rates for avascular necrosis are particularly expected in sickle cell disease, Gaucher disease, or kidney transplantation patients. Furthermore, the relatively young age of the patient with avascular necrosis should be seen as the main risk factor for higher revision rate. The results after resurfacing (today with known restricted indications) and cemented as well as cementless THA in aFKN are comparable for the appropriate indication to those in coxarthrosis or other diagnoses. Regardless of the underlying disease endoprosthetic treatment in aFKN leads to good results. Both cemented and cementless fixation techniques can be recommended.

[S3 guideline. Part 2: Non-Traumatic Avascular Femoral Head Necrosis in Adults - Untreated Course and Conservative Treatment]. / S3-Leitlinie. Teil 2: Atraumatische Femurkopfnekrose des Erwachsenen - unbehandelter Verlauf und konservative Behandlung.

BACKGROUND: In Germany there are 5000 to 7000 new cases of atraumatic avascular necrosis of the femoral head in adults per year. It occurs mostly in middle age. An increased frequency of idiopathic cases can be observed. Chemotherapy, corticoids and kidney transplants are frequently associated with the disease. In most cases the disease occurs on both sides. Early diagnosis is of particular importance, since in early stages it is most likely to avoid late damage with joint destruction. Whereas previously the temporary operational joint preservation and subsequent joint replacement were often the only option of treatment, conservative and joint-preserving measures today play an increasing role. MATERIAL AND METHODS: After the AWMF guidelines for S3 guideline clinical questions were formulated. Over the period from 01/01/1970 to 31/05/2013 a literature search was conducted. Systematic reviews, metaanalyses, original papers and clinical trials of all designs were evaluated. There were a total of 3715 references, of which 422 for the assessment regarding SIGN were eligible and finally 180 were in accord with the defined inclusion and exclusion criteria. For the untreated course and the assessment of conservative measures, a total of 42 references was suitable. In formulating the recommendations the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system was used, which distinguishes A "shall", B "should" and 0 "can". RESULTS AND CONCLUSION: If left untreated, the aFKN within 2 years leads to a subchondral fracture and subsequent collapse. After the diagnosis of femoral head necrosis, the risk of a disease of the opposite side is high within the next 2 years, then unlikely. The sole conservative treatment brings no benefit for the treatment of atraumatic avascular necrosis in the adult. Although it improves function, less pain can be obtained, and surgical intervention can be delayed, the progression is not stopped. Conservative treatment must therefore always be part of the overall treatment. In ARCO stage I to II Iloprost may be considered as a pharmacological approach to reduce the pain and the bone marrow oedema. This also applies to alendronate. Since this is an off-label use, and thus a therapeutic trial, an appropriate patient education must take place. For the use of anticoagulants and statins, there is no recommendation. Also the hyperbaric oxygen therapy, shock waves and pulsating electromagnetic fields or electrical stimulation cannot be recommended.

[Bone marrow edema and atraumatic necrosis of the femoral head : Therapy]. / Knochenmarködem und atraumatische Femurkopfnekrose : Therapie.

BACKGROUND: An increase in interstitial bony fluid occurs in bone-marrow edema (BME). The exact pathogenetic processes still remain unknown. BME is an unspecific finding that can occur on its own or accompany multiple diseases and pathologies. GOAL: Literature review and presentation of new guidelines. MATERIAL AND METHODS: This is a narrative literature review followed by current advice for the therapy of atraumatic osteonecrosis of the hip, based on the recently published S3-guidelines for this disease. RESULTS AND DISCUSSION: The differentiation of at least 3 different etiologies is proposed (mechanic, reactive and ischemic). Difficult, but important, is the distinction between the mostly painful, but benign entities (BME syndrome, bone bruise) and the progressive pathologies (osteonecrosis, arthritis, CRPS, tumour). Treatment options are dependent on etiology and clinic and can often be symptomatic. Core decompression is the surgical gold standard, leading to immediate pressure relief and therefore reduction in pain. Recently, it was shown that intravenous administration of Iloprost and bisphosphonates are also effective in achieving a reduction of BME and pain, with considerable improvement in the accompanying symptoms. The combination of core decompression and infusion seems to be another possible optimization ofthe therapy, in particular in the treatment of osteonecrosis.

The prevalence of vitamin D deficiency in patients with vertebral fragility fractures.

Hypovitaminosis D has been identified as a common risk factor for fragility fractures and poor fracture healing. Epidemiological data on vitamin D deficiency have been gathered in various populations, but the association between vertebral fragility fractures and hypovitaminosis D, especially in males, remains unclear. The purpose of this study was to evaluate serum levels of 25-hydroxyvitamin D (25-OH D) in patients presenting with vertebral fragility fractures and to determine whether patients with a vertebral fracture were at greater risk of hypovitaminosis D than a control population. Furthermore, we studied the seasonal variations in the serum vitamin D levels of tested patients in order to clarify the relationship between other known risk factors for osteoporosis and vitamin D levels. We measured the serum 25-OH D levels of 246 patients admitted with vertebral fractures (105 men, 141 female, mean age 69 years, sd 8.5), and in 392 orthopaedic patients with back pain and no fractures (219 men, 173 female, mean age 63 years, sd 11) to evaluate the prevalence of vitamin D insufficiency. Statistical analysis found a significant difference in vitamin D levels between patients with vertebral fragility fracture and the control group (p = 0.036). In addition, there was a significant main effect of the tested variables: obesity (p < 0.001), nicotine abuse (p = 0.002) and diabetes mellitus (p < 0.001). No statistical difference was found between vitamin D levels and gender (p = 0.34). Vitamin D insufficiency was shown to be a risk factor for vertebral fragility fractures in both men and women.

[Electromagnetic navigation of transpedicular punctures: more precise than the standard?]. / Elektromagnetische Navigation transpedikulärer Punktionen: Präziser als der Standard?

AIM: Before clinical implementation of an approved electromagnetic tracking system (CAPPA IRAD EMT) an experimental trial was performed to investigate the accuracy of the system and its safety in application for transpedicular vertebral punctures in comparison to the classical fluoroscopic method. MATERIAL AND METHODS: A total of 110 transpedicular punctures were performed bilaterally using 11 vertebrae of 5 realistic artificial phantoms and 1 pedicle was punctured with the conventional technique using c-arm fluoroscopy and the other with the electromagnetic tracking system. As a target a radiopaque non-ferromagnetic marker was implanted bilaterally in the anterior wall of the vertebrae. For evaluation of the precision the distance from the end of the puncture to the target and the gradual deviation of the actual channel from the ideal trajectory were assessed in three-dimensional computer tomography. Calculations and statistical analysis were performed according to the Wilcoxon test by means of SPSS 16.0.1 for Windows. RESULTS: The mean distance from the target was 6.6 mm (± 3.9 mm standard deviation SD) with electromagnetic navigation compared to 3.2 mm (± 2.8 mm SD) with fluoroscopic assistance and the mean aberration from the ideal trajectory was 18.4° (± 4.6° SD) compared to 6.5° (± 3.5° SD), respectively. The difference of accuracy was highly significant regarding both parameters (p < 0.001). CONCLUSIONS: The minimum requirement for accuracy of transpedicular punctures could not be achieved with electromagnetic navigation. Unless proven otherwise, the lack of accuracy is attributed to unstable referencing. Despite evidence of successful employment for soft tissue punctures the system cannot currently be recommended for osseous applications of the spine.

[Dihydrotestosterone improves the osseointegration of cobalt-chromium implants]. / Dihydrotestosteron verbessert die knöcherne Einheilung von Kobalt-Chrom-Implantaten.

BACKGROUND: The osseointegration of actually rarely implanted cobalt-chromium implants can be critical in an elderly population. The aim of our study was to evaluate the effect of preoperative testosterone treatment on the osseointegration of cobalt-chromium implants. MATERIALS AND METHODS: Press-fit implantation of 1.6 mm-diameter cobalt-chromium-molybdenum (CoCrMo) implants was performed in rats without pre-treatment in one group (n = 10) and after pre-treatment with 1 mg dihydrotestosterone (DHT) 2 days before surgery in the other group (n = 10). After 14 days, the specimens were examined by a pull-out test, histology and histomorphometry. RESULTS: The biomechanical testing delivered inconsistent data leading to no significant difference (6.45 ± 6.94 N vs. 4.66 ± 3.77 N). Histology showed closed contact between surrounding tissue and the implants in both groups. The bone/implant contact area was significantly enhanced after treatment with DHT (42.23 % ± 9.25 vs. 57.57 % ± 16.71, p < 0.05), while the ratio of osteoid was reduced (38.68 % ± 16.7 vs. 27.38 % ± 13.02, not significant). CONCLUSIONS: Pre-treatment with DHT enhances osseointegration of cobalt-chromium implants through enhanced mineralisation of peri-implant tissue. The treatment might additionally shorten postoperative rehabilitation due to its positive effects on musculature.

Cell-free repair of small cartilage defects in the Goettinger minipig: which defect size is possible?

PURPOSE: Cartilage repair of full-thickness chondral defects in the knees of Goettinger minipigs was assessed by treatment with cell-free collagen type-I gel plugs of three different sizes. METHODS: In 6 adult Goettinger minipigs, three full-thickness chondral defects were created in the trochlear groove of one knee of the hind leg. These defects were treated with a cell-free collagen type-I gel plug of 8, 10, or 12 mm diameter. All animals were allowed unlimited weight bearing. After 1 year, the animals were killed. Immediately after recovery, a non-destructive biomechanical testing was performed. The repair tissue quality was evaluated immunohistologically, collagen type-II protein was quantified, and a semiquantitative score (O'Driscoll score) was calculated. RESULTS: After 1 year, a high number of cells migrated into the initially cell-free collagen gel plugs and a hyaline-like repair tissue had been created. The O'Driscoll scores were: 8 mm, 21.2 (SD, 2.8); 10 mm, 21.5 (SD, 1.6); and 12 mm, 22.3 (SD, 1.0). The determination of the e-modulus, creep and relaxation revealed that mechanical properties of the two smaller defects were closer to unaffected hyaline cartilage. CONCLUSIONS: As cell-free collagen type-I gel plugs of all three different sizes created hyaline-like repair tissue, this system seems suitable for the treatment of even larger defects.

[Undergraduate curricular training in musculoskeletal ultrasound: the impact of preexisting anatomic knowledge]. / Kurrikulare Ultraschallausbildung am Bewegungsapparat: Einfluss der anatomischen Vorbildung auf die Weitergabe von Basis-Skills an der Schulter.

OBJECTIVE: The aim of this study was to evaluate the impact of students preexisting anatomic proficiency to address the fundamental problems related to musculoskeletal ultrasound (MSUS) training by assessing the peer-assisted learning (PAL) system. METHODS: Students without anatomic knowledge (first semester, n = 38) and students in their fourth semester of medical school (n = 49) were randomly assigned to two groups: 1) The PAL group - teaching by a group of three minimally trained student-teachers and 2) the Staff group - students were taught by a group of three ultrasound-experienced operators. Sessions included both a theoretical and a praxis component (DEGUM/EULAR, Toshiba Nemio™ XG, 10 MHz). A multiple choice questionnaire (MCQ) and an objective structured clinical examination (OSCE) were performed. Qualitative differences were evaluated by the Likert scale. RESULTS: Exposure included three separate lessons (each 120 minutes, 65 minutes of active scanning). The results of the MCQ were better among the fourth semester students than among those without anatomic knowledge (p < 0.001). Among first semester students, the MCQ results were better for those who had been taught by medical staff than for those who had been instructed by means of PAL (4.3 vs. 3.1; p = 0.045). At no point during the practical evaluation did significant differences arise between students of fourth and first semesters after medical staff tutoring (19.6 vs. 19.7 points; p = 0.978). PAL did result in worse results with regard to practical MSUS competence levels in the students possessing no previous knowledge (OSCE score 16.1; p = 0.042). CONCLUSIONS: Although deficits in theoretical knowledge cannot be compensated for, basic MSUS content appears to be adequately transferable to students with limited anatomic knowledge. Thus, an early implementation of MSUS during medical school education would be prudent, provided that the training is performed by an experienced MSUS operator.

[Influence of disc prosthesis position on segmental motion in the lumbar spine]. / Einfluss der Position einer lumbalen Bandscheibenprothese auf das segmentale Bewegungsverhalten.

AIM OF THE STUDY: Total disc arthroplasty is reported to maintain segmental motion. From finite element studies a rather posterior and central implantation of the prosthesis is recommended. However, there is yet no in vitro study with cadaveric specimens investigating the topic of implant positioning. METHODS: Ten human lumbar spines were subjected to biomechanical testing. Flexion/extension and side-bending moments were applied from 2.5-7.5 Nm on a spine load simulator. First, the intact specimens were tested in 3 load cycles while motion was monitored with regard to the facet joints under different loads by an ultrasound-based system. An unconstrained total disc prosthesis was then implanted in a central position and the different load cycles were repeated. Finally the implant was positioned in a decentral position with an average offset of 6.2 mm for repetitive data acquisition. RESULTS: Comparison of the facet joint motion in central and eccentric prosthesis positions resulted in the following averaged differences. During flexion of the lumbar spine an average difference of the reference point excursions of 0.38 mm was recorded on the ipsilateral facet joint with reference to the decentral position. For extension, the difference was 0.33 mm on average, for right side bending a difference of 0.63 mm was recorded while left side bending resulted in an average difference of 0.24 mm. The deviation of the reference markers on the contralateral facet joint showed the following average differences: for flexion 0.23 mm and for extension 0.54 mm, respectively. For side bending right/left the differences amounted to 0.18 mm and 0.39 mm. With regard to segmental motion there was no statistically significant difference for both the ipsilateral (p = 0.0564) and the contralateral (p = 0.2593) reference marker. CONCLUSIONS: The comparison of the segmental motion after central and decentral implantation of a lumbar total disc prosthesis reveals differences that have, nevertheless, no statistical significance. However, for clinical use it is recommended to strive for a central position of the implant.

[Muscular trunk stability in professional and amateur volleyball players]. / Volleyballspezifische Rumpfmuskelkraft bei professionellen und nicht professionellen Volleyballspielern.

AIM: The aim of this study was to analyse the efficiency of muscular activity in the trunk stabilisation of professional volleyball players compared to a group of amateur hobby players. The results were compared amongst the groups as well as with a reference group consisting of asymptomatic individuals. The question to be answered was whether or not professional volleyball players possess a characteristic strength profile in their trunk musculature and if differences exist with regard to the individuals' competitive playing level. METHOD: In this comparative study 12 professional volleyball players (German Bundesliga) and 18 non-professional volleyball players were analysed with regard to their isometric strength profile in all three planes. The reference group was provided by the Proxomed company, which had previously analysed healthy untrained individuals (n = 1045) of various age groups. RESULTS: A sports-specific profile for the musculature of volleyball players revealed a significant reduction in the flexion and rotation strength as well as a well-developed lateral flexion strength (highly significant when compared to the reference group). With reference to the level played, better strength values in flexion and lateral flexion were found among the professional athletes. CONCLUSIONS: Professional volleyball players present with a characteristic trunk musculature strength profile. A detailed analysis of the muscle strength of the spine as part of a sports medicine work-up could prove helpful in preventing injuries and overuse problems in professional and hobby volleyball players.

[Comparison of trunk muscle strength of soccer players with and without low back pain]. / Vergleich der Rumpfmuskelkraft von Fussballspielern mit und ohne Rückenschmerzen.

AIM OF THE STUDY: Low back pain in soccer players is one of the frequently appearing disorders caused by overuse. Myogenic dysbalances are under discussion as possible reason for this problem. In the present study the muscular strength profile of the trunk musculature of soccer players with and without low back pain was evaluated. The results of the asymptomatic players were compared to those of players with low back pain; furthermore, the collected data were compared to those of an asymptomatic reference group. The question posed was whether soccer players show a specific strength profile caused by the special, sports-specific requirements and whether this strength profile differs between players with and without low back pain. METHOD: In the present study the isometric maximal strength of 18 soccer players with and 18 soccer players without low back pain was measured in all 3 planes. The reference group was provided by the Proxomed company, which had previously analysed 1045 healthy untrained individuals of various age groups. RESULTS: The soccer players showed a sport-specific profile for the musculature, which was determined by a significant reduction of the flexion and rotation strength (flex: Ø 5.21 N/kg vs. Ø 6.49 N/kg; Ø 5.78 N/kg vs. Ø 6.66 N/kg respectively; rotation: left 7.09 N/kg, right 8.69 N/kg vs. left/right 10.1 N/kg; left 7.22 N/kg, right 8.24 N/kg vs. left/right 10.0 N/kg, respectively) as well as by an increased lateral flexion strength to the right-hand side in comparison to the reference group (lat. flex. right: 9.87 N/kg, respectively, 10.67 N/kg vs. 8.3 N/kg). A statistically significant correlation between the muscular activity in the trunk stability of soccer players with and without low back pain could not be shown. CONCLUSION: Obviously sports-specific training with additional specific training of the trunk muscles is not sufficient for the development of a balanced strength of trunk musculature. In the present study an influence of the performance of the trunk musculature on the incidence of low back pain could not be shown.

[Biomechanical analysis of lumbar spine after implantation of a disk prosthesis and supplementary spinal fusion for management of complications]. / Biomechanische Analyse der Lendenwirbelsäule nach Implantation einer Bandscheibenendoprothese sowie ergänzender Spondylodese als Komplikationsmanagement.

STUDY DESIGN: The aim of our investigations was to study the question as to what extent the mono- and multisegmental mobility of the lumbar spine (LS) differs after implantation of a disc prosthesis (DP) and if, in case of postoperative complications (dislocation or migration of the disc prosthesis), a sufficient stability of the motion segment can be achieved with a spinal fusion. To answer these questions we examined in corpse the mobility of the LS before and after DP implantation as well as after spinal fusion by using a load simulator for mobility and stability investigations of the lumbar spine. METHOD: After radiological exclusion of higher degenerative changes (X-ray in two planes) and exclusion of high-grade osteoporosis by using a pQ-CT scan with measurement of the bone mineral density (T score > -3.0), the first step was the multisegmental measurement of the thirteen unfixated LS specimens without DP by automatic electromechanical load-bearing. The measurements of mobility of the LS were done in flexion, extension, side-bending and side-rotation with a reproducible load of 10 Nm. The analysis of the movements during flexion and extension as well as side-bending and side-rotation were done by an ultrasonic detection system (zebris). In the second step the excursions were measured after implantation of the DP in L3/4 and in the third step after additional dorsal spinal fusion. RESULTS: After implantation of the artificial disc in L3/4 the mobility in side-bending and side-rotation increases in comparison to the LS without surgery. For side-bending we found an increasing amount up to +74 % for the single motion segment L3/4 and +3 % for the total LS, respectively, for the side-rotation an increase of mobility up to +72 % for the single motion segment L3/4 and +30 % for the total LS. On the other hand a decreased mobility of -11 % for flexion and extension was found with an artificial disc in comparison to the lumbar spine. After additional dorsal spinal fusion of L3/4 the mobility obviously decreases in all directions (flexion/extension -74 %, side-bending -75 %, side-rotation -51 %). CONCLUSION: The DP preserves (flexion/extension) and, respectively, improves (side-rotation/side-bending) the mobility of the LS. In cases of complications like dislocation or migration of the DP and secondary degenerative changes, the dorsal spinal fusion with restricted movements of the LS afterwards is a possible treatment solution.

[Perineural cysts causing severe back pain and pathological fracture of the massa lateralis of the sacrum]. / Perineurale sakrale Zysten als Ursache von Ischialgie und pathologischer Massa-lateralis-Fraktur des Os sacrum.

We report on the case of an 81-year-old woman who was hospitalised because of severe pain at the sacro-iliacal joint radiating into the left leg without any accompanying neurological defect. X-rays demonstrated a step in the left massa lateralis of the sacrum, thus CT scans and MRI were performed, and multiple perineural cysts (Tarlov's cysts) were found. The patient underwent microsurgical treatment by fenestration of the cyst wall and evacuation of the fluid content in order to avoid further expansion of the cysts. Under consequent treatment with pain killers, complete mobilisation of the patient could be achieved. Ambulant follow-up by clinical controls and X-rays demonstrated a substantial resolution of the patient's preoperative symptoms. Symptomatic perineural cysts should be included into differential diagnosis of severe low back pain, thus CT or MRI scans should be performed in case of long-lasting or intrackable pain.

[Procalcitonin (PCT) as diagnostic tool for the monitoring of spondylodiscitis]. / Procalcitonin (PCT) als Verlaufsparameter der Spondylodiszitis.

AIM: The diagnosis of spondylodiscitis is often prolonged, but it is an important differential diagnosis of backache. The discrimination between a bacterial infection and an aseptic inflammation with laboratory examinations like ESG, CRP or leukocytes is not possible. The aim of the present study was to determine the value of procalcitonin (PCT) as a diagnostic tool and monitoring parameter for spondylodiscitis and for the discrimination between bacterial infection and aseptic inflammation of the spine. METHOD: A total of 17 patients with spondylodiscitis and 18 patients with disc herniation as control were included in this study and ESG, CRP, leukocytes, fibrinogen, PNM elastase und PCT were examined for 50 days. The median age was 65 (17-78) years and the ratio of males to females was 8 : 9 in patients with spondylodiscitis and 62 (32-87) years and 7 : 11 in patients with disc herniation. For microbiological examination, CT-guided punctures were performed in patients with spondylodiscitis. RESULTS: In 64 % of the 17 patients with spondylodiscitis a microbiological agent was detected, in 73 % of these cases staphylococcus aureus was isolated. The laboratory parameters indicating an infection were increased except for two cases in patients with spondylodiscitis, the mean value of CRP was 115 mg/dL. Influenced by the therapy these parameters decreased during the observation period. Except for one patient with an infection of a cardiac pacemaker, the PCT concentration was not elevated in both groups (< 0.5 ng/mL). In the group with disc herniation there were no elevated laboratory parameters during the entire observation period. CONCLUSION: PCT is not useful as diagnostic tool or monitoring parameter for spondylodiscitis. Furthermore, it is not useful for the discrimination between a bacterial infection and an aseptic inflammation of the spine.

[Intravertebral pressure during vertebroplasty - an in-vitro study]. / Intravertebrale Druckentwicklung bei der Vertebroplastie - Eine anatomische In-vitro-Untersuchung.

INTRODUCTION: Extravasation of bone cement into the vertebral venous system during cement injection has been reported to be a major complication of percutaneous vertebroplasty. Therefore, high injection pressures during cement application into the fractured vertebral body are considered as one possible cause of cement leakage or extravasation. The aim of the current study was to measure the increase in intravertebral pressure caused by cement injection during vertebroplasty compared to the baseline venous pressure for the ascending lumbar vene. MATERIAL AND METHODS: In context of a cadaver study of 19 unfixed lumbar cadaver spines (L2-L5) [9 female, 10 male, 72 +/- 4.1 years] 19 vertebroplasties have been performed under operative conditions through a transpedicular approach. A manometer was placed in the lateral corticalis of each vertebral body for dynamic pressure measurement during 4 cement application cycles. Average and maximal intravertebral pressures as well as the average intravertebral pressure over the time of cement application ["area under the curve" (AUC)] were calculated. RESULTS: Average intravertebral pressure (10.9 +/- 12.6 kPa [min.: - 15.2 +/- 24.7 kPa; max.: 56.1 +/- 70.1 kPa]) showed a 13.6-fold increase compared to the baseline venous pressure for the ascending lumbar vein and a 70-fold increase compared to maximal pressure. During the 4 cement application cycles a continuous increase of the average intravertebral pressure over the application cycle (AUC) occurred. CONCLUSION: The 13.6-fold increase in intravertebral body pressure caused by cement injection during percutaneous vertebroplasty in comparison to the baseline venous pressure for the ascending lumbar vein might be one possible cause of the high rate of extravasation of bone cement reported in the current literature.