Staple Fixation in Ulnar-Shortening Osteotomies.

Ulnar-sided wrist pain is commonly caused by the ulnar impaction syndrome. Ulnar-shortening osteotomy is a surgical treatment that is used to address ulnar impaction syndrome that fails conservative management. Unfortunately, hardware irritation and nonunion are well-known complications of this procedure. This case report details the course of two patients with nonunion after ulnar-shortening osteotomy who were treated with a combination of a nitinol compression staple and neutralization plate. Further investigation is required to determine the long-term outcomes and indications for nitinol-staple fixation for nonunion after ulnar-shortening osteotomy.

Suppressing Chondrocyte Hypertrophy to Build Better Cartilage.

Current clinical strategies for restoring cartilage defects do not adequately consider taking the necessary steps to prevent the formation of hypertrophic tissue at injury sites. Chondrocyte hypertrophy inevitably causes both macroscopic and microscopic level changes in cartilage, resulting in adverse long-term outcomes following attempted restoration. Repairing/restoring articular cartilage while minimizing the risk of hypertrophic neo tissue formation represents an unmet clinical challenge. Previous investigations have extensively identified and characterized the biological mechanisms that regulate cartilage hypertrophy with preclinical studies now beginning to leverage this knowledge to help build better cartilage. In this comprehensive article, we will provide a summary of these biological mechanisms and systematically review the most cutting-edge strategies for circumventing this pathological hallmark of osteoarthritis.

Shoulder conditions and health related quality of life and utility: a current concepts review.

Study of the outcome of treatment of shoulder conditions has emphasized subjective evaluation of outcomes including a variety of disease, region, and joint-specific tools. In response to the rapidly rising cost of health care, further interest has been directed to cost-effectiveness and value. Comparison of the outcomes of different shoulder conditions with each other, other musculoskeletal, and nonorthopedic conditions requires more generalized outcome tools, especially when considering cost-effectiveness and utility analysis. The concept of quality of life (QoL) was developed to satisfy this goal, and there are a variety of general health and QoL assessments tools available. The purpose of this study is to review the concept of health-related QoL and discuss health-related QoL measures as they relate to shoulder conditions.

Humeral Avulsion of the Glenohumeral Ligament: Diagnosis and Management.

¼: The most common type of humeral avulsion of the glenohumeral ligament (HAGL) is a purely ligamentous avulsion involving the anterior inferior glenohumeral ligament (IGHL), but other variants are seen, including posterior lesions and those with an osseous avulsion. ¼: A central lesion between the intact anterior and posterior bands of the IGHL is gaining recognition as a distinct clinical entity. ¼: HAGL lesions are most commonly seen in patients with anterior instability without a Bankart tear or in those with persistent symptoms despite having undergone a Bankart repair. ¼: Magnetic resonance imaging is the most sensitive imaging modality. An arthrogram is helpful with subacute and chronic lesions when the joint is not distended. Arthroscopy is the gold standard for diagnosis. ¼: While some have reported success with nonoperative management, surgical repair with either arthroscopic or open techniques has provided a high rate of successful outcomes; however, the literature is limited to mostly Level-IV and V evidence.

Protein tyrosine phosphatases in skeletal development and diseases.

Skeletal development and homeostasis in mammals are modulated by finely coordinated processes of migration, proliferation, differentiation, and death of skeletogenic cells originating from the mesoderm and neural crest. Numerous molecular mechanisms are involved in these regulatory processes, one of which is protein posttranslational modifications, particularly protein tyrosine phosphorylation (PYP). PYP occurs mainly through the action of protein tyrosine kinases (PTKs), modifying protein enzymatic activity, changing its cellular localization, and aiding in the assembly or disassembly of protein signaling complexes. Under physiological conditions, PYP is balanced by the coordinated action of PTKs and protein tyrosine phosphatases (PTPs). Dysregulation of PYP can cause genetic, metabolic, developmental, and oncogenic skeletal diseases. Although PYP is a reversible biochemical process, in contrast to PTKs, little is known about how this equilibrium is modulated by PTPs in the skeletal system. Whole-genome sequencing has revealed a large and diverse superfamily of PTP genes (over 100 members) in humans, which can be further divided into cysteine (Cys)-, aspartic acid (Asp)-, and histidine (His)-based PTPs. Here, we review current knowledge about the functions and regulatory mechanisms of 28 PTPs involved in skeletal development and diseases; 27 of them belong to class I and II Cys-based PTPs, and the other is an Asp-based PTP. Recent progress in analyzing animal models that harbor various mutations in these PTPs and future research directions are also discussed. Our literature review indicates that PTPs are as crucial as PTKs in supporting skeletal development and homeostasis.

Atraumatic Displaced Femoral Neck Insufficiency Fracture Because of Severe Hypocalcemia in a Pediatric Patient: A Case Report.

CASE: This is a case of a 14-year-old autistic boy who presented with an atraumatic transcervical femoral neck fracture in the setting of significant hypocalcemia and vitamin D deficiency. We discuss his surgical and medical management and metabolic derangements associated with atraumatic femoral neck fractures. CONCLUSION: Pediatric femoral neck fractures in the absence of trauma are uncommon and often have underlying metabolic abnormalities. In addition, autism poses unique challenges in caring for these patients who are at an increased risk of complications. Interdisciplinary care is integral to achieving successful outcomes.

Apolipoprotein E is a pancreatic extracellular factor that maintains mature ß-cell gene expression.

The in vivo microenvironment of tissues provides myriad unique signals to cells. Thus, following isolation, many cell types change in culture, often preserving some but not all of their in vivo characteristics in culture. At least some of the in vivo microenvironment may be mimicked by providing specific cues to cultured cells. Here, we show that after isolation and during maintenance in culture, adherent rat islets reduce expression of key ß-cell transcription factors necessary for ß-cell function and that soluble pancreatic decellularized matrix (DCM) can enhance ß-cell gene expression. Following chromatographic fractionation of pancreatic DCM, we performed proteomics to identify soluble factors that can maintain ß-cell stability and function. We identified Apolipoprotein E (ApoE) as an extracellular protein that significantly increased the expression of key ß-cell genes. The ApoE effect on beta cells was mediated at least in part through the JAK/STAT signaling pathway. Together, these results reveal a role for ApoE as an extracellular factor that can maintain the mature ß-cell gene expression profile.