Patellaluxation

The patella dislocation is defined as a non-recurring or recurrent dislocation of the patella from the patella surface of the femur. In general the patella dislocates in the lateral direction. Patella dislocations are subdivided in congenital, habitual or traumatic dislocations. Furthermore patella dislocations are differentiated in recurrent and chronic dislocations. Etiology of patella dislocations is not consistent and can be due to genu valgum, patella dysplasia or patella alta etc. Frequently the patella reposes spontaneously after dislocation. Besides examination of the knee, x-ray and magnetic resonance tomography belong to clinical diagnostics of the knee joint. Decision between conservative and operative therapy is addicted to accompanying injuries like fractures or ligamental injuries.     

S100B in underweight and weight-recovered patients with anorexia nervosa

Anorexia nervosa (AN) commonly arises during adolescence, leading to interruptions of somatic and psychological development as well as to cortical atrophy and reductions of brain volume. While most brain changes shift towards normal with weight restoration, it is not certain whether they are related to the loss of brain cells, neuropil or merely due to fluid shifts. We measured S100B serum concentrations and psychometric characteristics in 34 patients with acute AN, 19 weight-recovered patients and 35 healthy control women (HCW). Plasma tryptophan and leptin levels were determined as markers for malnutrition and neuroendocrine adaptation to semi-starvation. Peripheral S100B concentrations of acute and former AN patients were not elevated and not statistically different from HCW. BMI, peripheral leptin levels and measures of psychopathology as well as executive cognitive functioning did not correlate with S100B. Plasma tryptophan was positively related to S100B. Our results are in line with our previous findings showing unaltered GFAP and NSE plasma levels in patients with acute AN. Together they do not support hypotheses comprising the degeneration of glial or neuronal cells to explain common signs of brain atrophy in patients with acute AN.     

Assessment of metastatic liver disease in patients with primary extrahepatic tumors by contrast-enhanced sonography versus CT and MRI

AIM: To evaluate contrast-enhanced ultrasonography (CEUS) using SonoVue(?) in the detection of liver metas-tases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI and clinical/histological data. METHODS: It is an international multicenter study, and there were 12 centres and 125 patients (64 males, 61 females, aged 59±11 years) involved, with 102 patients per protocol. Primary tumors were colorectal in 35%, breast in 27%, pancreatic in 17% and others in 21%. CEUS using SonoVue(?) was employed with a low-mechanical-index technique and contrast-specific software using Siemens Elegra, Philips HDI 5000 and Acuson Sequoia; continuous scanning for at least five minutes. RESULTS: CEUS with SonoVue(?) increased significantly the number of focal liver lesions detected versus unen-hanced sonography. In 31.4% of the patients, more lesions were found after contrast enhancement. The total numbers of lesions detected were comparable with CEUS (55), triple-phase spiral CT (61) and MRI with a liver-specific contrast agent (53). Accuracy of detection of metastatic disease (i.e. at least one metastatic lesion) was significantly higher for CEUS (91.2%) than for un-enhanced sonography (81.4%) and was similar to that of triple-phase spiral CT (89.2%). In 53 patients whose CEUS examination was negative, a follow-up examination 3-6 months later confirmed the absence of metastatic lesions in 50 patients (94.4%). CONCLUSION: CEUS is proved to be reliable in the detection of liver metastases in patients with known extra-hepatic primary tumors and suspected liver lesions.     

Thrombocytes are effectors of the innate immune system releasing human beta defensin-3

Background

Thrombocyte concentrate i.e. platelet-rich plasma (PRP) has become a popular adjunct for many surgical procedures. It is believed to improve bone and soft tissue healing. Recently antimicrobial effects of the autologous preparation were reported by several groups. In this study we investigated the antimicrobial effect of PRP against gram-negative microbes which frequently cause severe complications in orthopaedic trauma surgery.

Methods

Platelet-rich plasma was produced from liquid preserved thrombocyte concentrates. ELISA, Western blot and immunohistochemistry were preformed to investigate the release and content of platelet concentrates. A radial diffusion assay was used to detect antimicrobial effects of PRP.

Results

We detected the human beta defensin-3 in bactericidal concentrations in platelet preparations by ELISA, Western blot and immunohistochemistry. In antimicrobial testing we demonstrated effective inhibition of Escherichia coli (ATCC 11303), Bacterium megaterium (ATCC 14581), Klebsiella pneumoniae (ATCC 13883), Enterococcus faecalis (ATCC 29212) and Proteus mirabilis (ATCC21100).

Conclusion

With this study we demonstrate antimicrobial action of a popular adjunct for orthopaedic and trauma surgery against gram-positive and gram-negative bacteria. We have identified a possible mechanism of action via the secretion of HBD-3 as a first line defence in contaminated wounds and in elective application of PRP. This finding supports a broader spectrum of clinical indications for an autologous platelet preparation.     

A Biomechanical Evaluation to Optimize the Configuration of a Hinged External Fixator for the Primary Treatment of Severely Displaced Intraarticular Calcaneus Fractures with Soft Tissue Damage

The purpose of this investigation was to develop an optimized hinged external fixator for the primary treatment of dislocated, intra-articular calcaneus fractures with associated soft tissue damage. To this end, a calcaneus model was made out of a polyurethane block, and a steel cylinder served as the ankle joint and was connected to a synthetic model of the tibia via a metal clamp. A saw cut served as the fracture in the model. A Steinmann nail and Schanz screw were placed in defined positions in the model and connected medially and laterally with longitudinal support rods. The fixator allowed a total of 20 degrees of plantar- and dorsiflexion, with rotation in the virtual axis of the upper ankle joint. Changes in the model fracture were measured during cyclical strain, and at different screw positions in the model tibia and calcaneus. Miniature force sensors located on the longitudinal support rods, and a plantar tension spring, were used to measure pressure and tension. Reproducible values were determined and, with the optimal configuration, shifting within the osteotomy was minimal. In the experimental configuration, optimal tibial screw placement was 70 mm proximal to the rotation axis of the upper ankle joint, and optimal placement of the Steinmann nail was in the posterior surface of the calcaneus. These findings indicated that the hinged fixator allows 20 degrees of ankle movement without alteration of the rotation axis, and suggest that this type of external fixator can be used in all types of calcaneal fracture regardless of the soft tissue damage. ACFAS Level of Clinical Evidence: 5c.     

A new semirigid implant for instrumentation of scoliosis: preliminary report

A new set of pedicle screws, lamina and pedicle hooks, longitudinal rods and a titanium cable was developed to overcome the increasingly obvious hazards of overly rigid spinal instrumentation. Results of the first 12 consecutive scoliosis patients with this new system are reported, with an average follow-up time of 18 months. No major complications occurred. The average correction of the deformity was well within the range of more rigid systems. The new Dorsal Dynamic Spondylodesis (DDS) system proved to be easy to use, fast, powerful, safe, versatile, and biomechanically sound. Reduction of stress-shielding effects and protection of adjacent segments can be expected, and the system warrants future application in selected prospective cases with long-term follow-up.     

Assessment of the technical usability and efficacy of a new portable dry-electrode EEG recorder: First results of the HOMEONE study

ObjectivesThe HOME project is intended to provide evidence of diagnostic and therapeutic yield of a patient-controlled EEG home-monitoring for neurological outpatients.MethodsThis study evaluated the technical and practical usability and efficacy of a new portable dry-electrode EEG recorder in comparison to conventional EEG devices based on technical assessments and inter-rater comparisons of EEG record examinations of office-based practitioners and two experienced neurologists.ResultsThe technical assessment was based on channel-wise comparisons of band power values derived from power spectra as observed in two recording modalities. Slight yet significant differences were observed only in the Delta-frequency band (1.5–4 Hz). The fraction of automatically detected artifact segments was larger in the new portable recordings than in conventional recordings (20% vs. 11%, median). Overall, 93% of raters’ stated diagnostic findings gathered from conventional devices were concordant with stated diagnostic findings gathered from the new portable device.ConclusionThe new EEG device was shown to have technical comparability to and a high concordance rate of diagnostic findings with conventional EEG devices.SignificanceThe new portable dry-electrode EEG device is suitable to meet the HOME projects’ goal of establishing a patient-controlled EEG home-monitoring in the routine care of neurological outpatients.Trial registrationDRKS DRKS00012685. Registered 09 August 2017, retrospectively registered.