Experimental guide wire placement for total shoulder arthroplasty in glenoid models: higher precision for patient-specific aiming guides compared to standard technique without learning curve.

Background: Patient-specific aiming devices (PSAD) may improve precision and accuracy of glenoid component positioning in total shoulder arthroplasty, especially in degenerative glenoids. The aim of this study was to compare precision and accuracy of guide wire positioning into different glenoid models using a PSAD versus a standard guide.

Methods: Three experienced shoulder surgeons inserted 2.

Tendon Repair Leads to better Long-Term Clinical Outcome than Debridement in Massive Rotator Cuff Tears.

Introduction: Massive tears in the rotator cuff are debilitating pathologies normally associated with loss of function and pain. Tendon reconstruction is seen as the standard treatment in order to preserve shoulder function and to inhibit cuff associated osteoarthritis. However, the effect on longer-term shoulder function and patient satisfaction is unknown.

Resurfacing of the humeral head: An analysis of the bone stock and osseous integration under the implant.

Cementless-surface-replacement-arthroplasty (CSRA) of the shoulder aims for functional joint restoration with minimal bone loss. Good clinical results have been reported, but due to the radiopaque metal shell no data is available on the structure, osseous integration, and bone stock under the implant. 14 hemi-CSRAs (4 manufacturers) with two geometries (crown [n = 7]/ stem [n = 7] fixation) were retrieved from patients undergoing revision due to glenoidal erosion.

Straight proximal humeral nails are surrounded by more bone stock in comparison to bent nails in an experimental cadaveric study.

Background: In the management of proximal humeral fractures intramedullary implants with bent and straight shape of the proximal part of nail are available. Based on data from previous studies on bone distribution in the humeral head, we hypothesized, that higher densities might exist in the bone stock surrounding straight nails in comparison to their angulated counterparts. With a known positive correlation between bone density and mechanical stability, this could indicate potentially higher rigidity of osteosyntheses done with straight implants.

Long-term functional outcomes (median 10 years) after locked plating for displaced fractures of the proximal humerus.

Background: Locked plating has become an accepted treatment for displaced fractures of the proximal humerus. However, to our knowledge, long-term outcomes have not been reported.

Methods: Between February 2002 and March 2004, 121 patients with displaced proximal humeral fractures were treated by open reduction and locking plate fixation.

Sequential effects in continued visual search: using fixation-related potentials to compare distractor processing before and after target detection.

To search for a target in a complex environment is an everyday behavior that ends with finding the target. When we search for two identical targets, however, we must continue the search after finding the first target and memorize its location. We used fixation-related potentials to investigate the neural correlates of different stages of the search, that is, before and after finding the first target.

[Reverse shoulder arthroplasty for primary fracture treatment. Displaced three and four part fractures of the proximal humerus in the elderly patient].

The treatment of comminuted three and four part fractures of the proximal humerus in elderly patients with degenerative rotator cuff tears is challenging. Primary reverse total shoulder arthroplasty (RSA) is an alternative; however, functional outcome is still unclear due to a lack of study results. The aim of this study was to examine the functional results of RSA and to compare them with the results after reconstruction and locking plate osteosynthesis 1 year after surgery.

[Proximal humerus fractures. Decisive factors for therapy choice, treatment and complications].

The majority of proximal humerus fractures are treated conservatively resulting in satisfying results. Fractures which need to be treated operatively are challenging for the therapist, postoperative treatment and the patient. It is inadequate to establish a therapy concept only by using radiological images and the resulting classification.

Individual differences in solving arithmetic word problems.

Background: With the present functional magnetic resonance imaging (fMRI) study at 3 T, we investigated the neural correlates of visualization and verbalization during arithmetic word problem solving. In the domain of arithmetic, visualization might mean to visualize numbers and (intermediate) results while calculating, and verbalization might mean that numbers and (intermediate) results are verbally repeated during calculation. If the brain areas involved in number processing are domain-specific as assumed, that is, that the left angular gyrus (AG) shows an affinity to the verbal domain, and that the left and right intraparietal sulcus (IPS) shows an affinity to the visual domain, the activation of these areas should show a dependency on an individual's cognitive style.

Investigating the influence of proficiency on semantic processing in bilinguals: an ERP and ERD/S analysis.

In this study, we presented sentences either ending with high or low probability cloze words or semantically incongruent words to investigate the influence of L2 proficiency on electrophysiological correlates of semantic processing in bilinguals. Event-related potentials (ERPs) as well as the oscillatory dynamics of the EEG signal, specifically, frequency power changes expressed as event-related (de)synchronization (ERD/S), were analyzed. Replicating earlier results, we found an N400 on semantically incongruent words, as well as on low cloze probability words.

Significant benefit for older patients after arthroscopic subacromial decompression: a long-term follow-up study.

Background: Patients suffering from isolated subacromial impingement (SI) of their shoulder but who are resistant to other therapies benefit substantially from arthroscopic subacromial decompression (ASD) if they are young (<60 years). Although physical demands rise notably in the older population, it still remains unclear if surgery leads to better results in these patients. Therefore, the aim of this study was to focus on the impact of age on the functional outcome in elderly patients suffering from SI.

X-treme CT analysis of cancellous bone at the rotator cuff insertion in human individuals with osteoporosis: superficial versus deep quality.

Purpose: Rotator cuff (RC) repair-especially in the elderly population-is problematic since the patients suffer to a high extent from bone mineral density loss at the reattachment site. Therefore, the study was primarily driven by the question whether it is possible to reach more or qualitatively better cancellous bone and thus a more stable postoperative result if anchors with greater length are used for RC repair and/or the conventional anchors are screwed deeper into the bone. In anatomical terms, the question is raised whether cancellous bone is of better quality close to or far off the RC enthesis.

Age and gender as determinants of the bone quality of the greater tuberosity: a HR-pQCT cadaver study.

Background: Age-dependent trabecular changes of the humeral head might weaken the fixation of suture anchors used for rotator cuff (RC) repair. This might lead to suture anchor loosening and thus compromise the integrity of the repair. The aim of this study was to analyze whether the trabecular microstructure within the RC footprint is influenced by age, gender or handedness.

Footprint reconstruction in a rotator cuff tear associated cyst of the greater tuberosity: augmented anchorage.

Tears of the rotator cuff (RC) complicated by bone cysts at the footprint might represent a challenge for the shoulder surgeon. This might be additionally aggravated in elderly patients with inferior bone quality due to osteopenia or osteoporosis. In this report we present a technique for open repair of RC tears by augmenting the cystic lesion at the greater tuberosity using bone void filler in combination with a double row anchor reconstruction technique.

Tension band wiring of the olecranon: is it really a dynamic principle of osteosynthesis?

The tension band principle as applied to transverse olecranon fractures fixed by tension band wiring is based on the premise that distraction forces on the outer cortex of the ulna during elbow flexion are converted to compression forces on the articular surface of the olecranon at the fracture site. In view of some clinical outcomes, where hardware failure and secondary dislocations occur, the question arises if the dynamic compression theory is correct. Compressive forces during active flexion and extension after tension band wiring of a transverse osteotomy of the olecranon were measured in 6 fresh frozen human cadaveric models using a pressure-sensor in the osteotomy gap.

The Munich Shoulder Questionnaire (MSQ): development and validation of an effective patient-reported tool for outcome measurement and patient safety in shoulder surgery.

Background: Outcome measurement in shoulder surgery is essential to evaluate the patient safety and treatment efficiency. Currently this is jeopardized by the fact that most patient-reported self-assessment instruments are not comparable. Hence, the aim was to develop a reliable self-assessment questionnaire which allows an easy follow-up of patients.

The Influence of verbalization on the pattern of cortical activation during mental arithmetic.

Background: The aim of the present functional magnetic resonance imaging (fMRI) study at 3 T was to investigate the influence of the verbal-visual cognitive style on cerebral activation patterns during mental arithmetic. In the domain of arithmetic, a visual style might for example mean to visualize numbers and (intermediate) results, and a verbal style might mean, that numbers and (intermediate) results are verbally repeated. In this study, we investigated, first, whether verbalizers show activations in areas for language processing, and whether visualizers show activations in areas for visual processing during mental arithmetic.

Fibrocartilage in various regions of the human glenoid labrum. An immunohistochemical study on human cadavers.

Purpose: The nature and the distribution of fibrocartilage at the human glenoid labrum are unclear, and a better understanding may help to restore its function in open and arthroscopic Bankart repair. Aim of this study was to describe the fibrocartilage extent within the labrum at clinically relevant sites of the glenoid in order to relate the molecular composition of the labrum to its mechanical environment.

Methods: Twelve fresh frozen human cadaveric shoulders (mean age 38 years) were obtained, and sections perpendicular to the glenoid rim at the 12, 2, 3, 4, 6 and 9 o' clock position were labelled with antibodies against collagen I and II, aggrecan and link protein.

Comparison of intraosseous versus central venous vascular access in adults under resuscitation in the emergency department with inaccessible peripheral veins.

Introduction: Current European Resuscitation Council (ERC) guidelines recommend intraosseous (IO) vascular access, if intravenous (IV) access is not readily available. Because central venous catheterisation (CVC) is an established alternative for in-hospital resuscitation, we compared IO access versus landmark-based CVC in adults with difficult peripheral veins.

Methods: In this prospective observational study we investigated success rates on first attempt and procedure times of IO access versus central venous catheterisation (CVC) in adults (≥ 18 years of age) with inaccessible peripheral veins under trauma or medical resuscitation in a level I trauma centre emergency department.

[Comparison of regional distribution of cancellous bone in osteoporotic and non-osteoporotic distal radii].

Background: In cases of distal radius fractures information about the regional distribution of cancellous bone is essential for adequate fixation of osteosynthesis material.

Materials And Methods: Using quantitative computed tomography (qCT) measurements 12 distal radii were divided into 2 groups (good and bad bone quality). High-resolution CT scans were obtained at 13 locations (1-40 mm distant from radial styloid processes).

Treatment of distal humeral fractures using conventional implants. Biomechanical evaluation of a new implant configuration.

Background: In the face of costly fixation hardware with varying performance for treatment of distal humeral fractures, a novel technique (U-Frame) is proposed using conventional implants in a 180 degrees plate arrangement. In this in-vitro study the biomechanical stability of this method was compared with the established technique which utilizes angular stable locking compression plates (LCP) in a 90 degrees configuration.

Methods: An unstable distal 3-part fracture (AO 13-C2.

Malfunction of a Heimlich flutter valve causing tension pneumothorax: case report of a rare complication.

Background: Thoracic injuries play an important role in major trauma patients due to their high incidence and critical relevance. A serious consequence of thoracic trauma is pneumothorax, a condition that quickly can become life-threatening and requires immediate treatment.Decompression is the state of the art for treating tension pneumothorax.