Medial Dislocation of the Long Head of the Biceps without Concomitant Subscapularis Tear: A Case Report.

INTRODUCTION: Medial dislocation of the long head of the biceps tendon (LHBT) is classically known as a pathognomonic finding for a subscapularis or at least a rotator cuff (RC) injury. However, this case report outlines a young active individual with symptomatic medial dislocation of the long head of the biceps with associated posterior instability, without a corresponding RC injury. CASE REPORT: An 18-year-old male complained of the left shoulder pain and crepitus after a shoulder injury while playing hockey a year prior. Magnetic resonance imaging demonstrated medial dislocation of the LHBT without subscapularis or supraspinatus tendon injury. The patient complained of instability in the shoulder and exam findings supported posterior instability of the glenohumeral joint. Arthroscopic debridement of the glenohumeral joint with arthroscopic posterior capsulorrhaphy and open biceps tenodesis was performed. The patient regained full and painless range of motion at 2-year follow-up. CONCLUSION: Medial dislocation of the LHBT can occur without injury to the subscapularis tendon. Furthermore, a capsulorrhaphy with open biceps tenodesis and closure of the rotator interval may provide a successful outcome for this rare injury pattern.

Image, geometry and finite element mesh datasets for analysis of relationship between abdominal aortic aneurysm symptoms and stress in walls of abdominal aortic aneurysm.

These datasets contain Computed Tomography (CT) images of 19 patients with Abdominal Aortic Aneurysm (AAA) together with 19 patient-specific geometry data and computational grids (finite element meshes) created from these images applied in the research reported in Journal of Surgical Research article "Is There A Relationship Between Stress in Walls of Abdominal Aortic Aneurysm and Symptoms?"[1]. The images were randomly selected from the retrospective database of University Hospitals Leuven (Leuven, Belgium) and provided to The University of Western Australia's Intelligent Systems for Medicine Laboratory. The analysis was conducted using our freely-available open-source software BioPARR (Joldes et al., 2017) created at The University of Western Australia. The analysis steps include image segmentation to obtain the patient-specific AAA geometry, construction of computational grids (finite element meshes), and AAA stress computation. We use well-established and widely used data file formats (Nearly Raw Raster Data or NRRD for the images, Stereolitography or STL format for geometry, and Abaqus finite element code keyword format for the finite element meshes). This facilitates re-use of our datasets in practically unlimited range of studies that rely on medical image analysis and computational biomechanics to investigate and formulate indicators and predictors of AAA symptoms.

Is There a Relationship Between Stress in Walls of Abdominal Aortic Aneurysm and Symptoms?

BACKGROUND: Abdominal aortic aneurysm (AAA) is a permanent and irreversible dilation of the lower region of the aorta. It is typically an asymptomatic condition that if left untreated can expand to the point of rupture. In simple mechanical terms, rupture of an artery occurs when the local wall stress exceeds the local wall strength. It is therefore understandable that numerous studies have attempted to estimate the AAA wall stress and investigate the relationship between the AAA wall stress and AAA symptoms. MATERIALS AND METHODS: We conducted computational biomechanics analysis for 19 patients with AAA (a proportion of these patients were classified as symptomatic) to investigate whether the AAA wall stress fields (both the patterns and magnitude) correlate with the clinical definition of symptomatic and asymptomatic AAAs. For computation of AAA wall stress, we used a very efficient method recently presented by the Intelligent Systems for Medicine Laboratory. The Intelligent Systems for Medicine Laboratory's method uses geometry from computed tomography images and mean arterial pressure as the applied load. The method is embedded in the software platform BioPARR-Biomechanics based Prediction of Aneurysm Rupture Risk, freely available from http://bioparr.mech.uwa.edu.au/. The uniqueness of our stress computation approach is three-fold: i) the results are insensitive to unknown patient-specific mechanical properties of arterial wall tissue; ii) the residual stress is accounted for, according to Y.C. Fung's Uniform Stress Hypothesis; and iii) the analysis is automated and quick, making our approach compatible with clinical workflows. RESULTS: Symptomatic patients could not be identified from the plots (pattern) of AAA wall stress and stress magnitude. Although the largest stress was predicted for a patient who suffered from AAA symptoms, the three patients with the smallest stress were also symptomatic. CONCLUSIONS: The results demonstrate, contrary to the common view, that neither the wall stress magnitude nor the stress distribution appears to be associated with the presence of clinical symptoms.

Near-simultaneous bilateral reverse total shoulder arthroplasty for the treatment of bilateral fracture dislocations of the shoulder.

A man in his mid-80s presented with bilateral posterior fracture dislocations of the humerus after suffering a seizure. He had Parskinson's disease and lived with his wife at home. His left shoulder was not felt to be reconstructable. The initial treatment plan was to perform reverse total shoulder arthroplasty (rTSA) on the left and non-operatively reduce his right shoulder. A left rTSA was performed, but his right shoulder was unstable due to a glenoid fracture and soft tissue instability. In order to preserve the patient's quality of life, a right rTSA was performed 4 days later. In the follow-up period, the patient was able to regain enough pain-free range of motion on activities of daily living. The patient died from complications of Parkinson's disease 10 months postoperatively.

How do health professionals decide whether an interpreter is needed for families in neonatal and pediatric units?

OBJECTIVE: To examine how health professionals decide whether family members require an interpreter. METHODS: 69 health professionals, doctors, nurses, and allied health, from neonatal and pediatric units participated. Interviews used a verbal protocol analysis, which elicited their thoughts about using interpreters, including how they decided if an interpreter was needed. RESULTS: Five themes captured the decision-making process health professionals use. Of these, three themes described the goals and beliefs participants brought to their interactions with family members: Ensuring understanding, Addressing socioemotional needs, and Who decides. The theme Assessing understanding was prominent within the interaction, while the final theme was Contextual factors influencing decision making. No differences were found between mono and multilingual participants, and few differences between health professional groups. CONCLUSION: Health professionals find it difficult to assess whether a family member needs an interpreter and there is no consistency in how they make this decision, with some using heuristics and others a more systematic approach. Health professionals have beliefs about the purpose of an interpreter that potentially limit the voice of family members. PRACTICE IMPLICATIONS: Health professionals need training to assist them in decisions about whether an interpreter is needed, including a decision tool and knowledge about policies.

Optimization of the racking hitch knot: how many half hitches and which suture material provide the greatest security?

BACKGROUND: Reliable methods of fixation of soft tissue and bone are of utmost importance in reconstructive shoulder surgery and in many orthopaedic applications. Current methods of securing lesser tuberosity osteotomies performed during shoulder arthroplasty and tuberosity fixation performed during repair of proximal humeral fractures often rely on alternating half hitches or surgeon's knots regardless of the suture configuration used passing through the tissue (eg, Mason-Allen, Krackow). The racking hitch knot in contrast to half hitches allows sequential tightening, even under tension, with minimal risk of knot slippage or premature locking. These knot characteristics allow the surgeon to stepwise improve their reduction before committing and locking a construct, preventing hanging knots or under-tensioned repairs. However, little data exist to support the use the racking hitch knot to guide decision making regarding how to back up the knot or to explain the effect of suture material on security and strength. QUESTIONS/PURPOSES: The objectives of our study were (1) to identify the optimal number of half hitches necessary to maintain knot security for a single knot; (2) to evaluate if a difference exists in the relative behavior of racking hitch knots when tied using different suture materials; and (3) to define the biomechanical differences between the racking hitch and two other knot configurations commonly used in shoulder surgery (Weston and square knots). METHODS: Using an Instron device we tested the effect of adding supplemental half hitches (from one to four) to the racking hitch. Additionally, a selection of commercially available braided nonabsorbable polyethylene sutures and different knot configurations (racking hitch, Weston knot, and square knot) also were tested. Data were compared using ANOVA. RESULTS: Increasing the number of half hitches improved knot performance in peak load testing and cyclic testing, revealing a significant difference between the racking hitch supplemented with one and four half hitches (199.2 N versus 428.8 N, p < 0.05). Force Fiber™ #2 (359.6 N) and FiberWire(®) #2 (302 N) showed increased loads to failure compared with Ethibond Excel™ #2 or Force Fiber™ #3/4, whereas Ethibond Excel™ had the least amount of slippage during cyclic testing (0.09 mm). The racking hitch knot had considerably higher loads to failure (359.6 N) than the Weston (145.2 N) or square (77 N) knots. CONCLUSIONS: The racking hitch knot exhibited significantly higher loads to failure and comparable knot slippage (elongation during cyclic testing) when compared with other commonly used knots. According to the biomechanical data, the addition of four half hitches to supplement the racking hitch and the choice of FiberWire(®) #2 or Force Fiber™ #2 suture resulted in increased knot security. CLINICAL RELEVANCE: This knot adds a tool to the arsenal for surgeons best suited for repairs requiring a high degree of knot security and reliable tissue tensioning.

A classification-based treatment algorithm for Kienböck disease: current and future considerations.

Kienböck disease is an isolated disorder of the carpal lunate associated with characteristic, and often progressive, clinical and radiographic changes. Appropriate intervention at specific disease stages represents the best opportunity to achieve good outcomes. As understanding of the disease improves, new therapeutic and diagnostic innovations have surfaced that further augment existing treatment options. Biologic, not just traumatic, processes may explain the onset and progression through the disease continuum. In addition to observing the obvious osseous changes, there has been renewed interest in understanding the vascular and cartilaginous manifestations of the disorder. Recognition of these factors can permit focused areas of intervention, including gene and cell-based therapies in the earliest stages. New diagnostic techniques are also being investigated. Advanced imaging modalities can facilitate the earlier recognition of Kienböck disease and enhance the assessment of lunate vascularity. Moreover, diagnostic arthroscopy permits us to directly visualize and characterize affected structures, including cartilage. Finally, there has been much recent interest in the natural history of Kienböck disease. Infantile, juvenile, and geriatric forms have been described. It has been suggested that the disease pathway in these individuals may differ from the typical adult patient population. Integrating these contemporary findings with the classic information on Kienbock disease can permit a more sophisticated approach to stage-specific treatment. This article reexamines the current classification systems to account for these emerging concepts.