The vascular basis of the hemi-hamate osteochondral free flap. Part 2: surgical anatomy and clinical application

Purpose

The free vascularised hemi-hamate flap combines the utility of providing a small osteochondral portion of hamate for reconstruction, while providing a means of vascularisation to preserve articular cartilage after transfer. In Part 1 of this series, we highlighted the vascular approaches to such a technique. The current study investigates the bony architecture of the hamate, with particular emphasis on its utility for a range of osteochondral defects in the hand.

Methods

A morphometric assessment of the hamate as a potential osteochondral flap donor site for resurfacing digital phalangeal heads (either total or unicondylar) and/or bases was thus undertaken. This anatomic study was undertaken using in vivo imaging performed for a range of clinical indications, with computed tomographic angiography (CTA) and digital subtraction angiography (DSA) of the upper limb included. Bony and vascular measurements and relationships were recorded and assessed both quantitatively and qualitatively. A clinical case is presented, highlighting the application of these measurements.

Results

The mean digital artery diameter was 0.7 mm with a mean distance between digital artery and interphalangeal joint surface (i.e. pedicle length) of 1.18 mm. Mean hamate dimensions comprised a transverse width 16.62 mm, lateral width of 14.29 mm and ridge height of 1.43 mm. Measurements of the phalangeal bases, condyles and total phalangeal heads were recorded, and the optimal hamate harvest approaches demonstrated. Despite perceived differences, in all cases there was statistical similarity demonstrated between the fragments.

Conclusion

The hemi-hamate osteochondral flap can be applied to a range of osteochondral defects in the hand and may offer new options to the hand surgeon.     

Outcomes of endodontically treated cracked teeth: a systematic review and meta-analysis

Clinical Oral Investigations - Systematic review analyzing the treatment outcomes of cracked teeth that received endodontic treatment is unavailable. The purpose of this study was to examine the...     

The Impact of Music on Patient Satisfaction,Anxiety, and Depression in Patients Undergoing Gynecologic Surgery

PurposeThe project piloted a perioperative music listening program to explore the feasibility and acceptability of the use of music in a perioperative setting for female surgical patients in an academic hospital in Singapore. The aim was also to examine the most commonly chosen music genres, timing, and length of time listening to music for perioperative patients to assess the impact of music on patients' satisfaction, anxiety, and depression.DesignThis was a quality improvement project.MethodsMusic playlists developed by a music therapist were installed on three iPod Touch^TM devices (Apple, Cupertino, CA). After obtaining consent, female patients undergoing elective gynecologic day surgery selected their preferred music from the playlists on the iPods to listen to during the preoperative and postoperative periods. Patients' anxiety and depression were measured using the Hospital Anxiety and Depression Scale and the three-level version of the EuroQol five-dimensional questionnaire. Patients' satisfaction with listening to music, duration, and chosen music genres were recorded.FindingsIn the project, 135 patients listened to music during the preoperative period, and 70 patients chose to listen to music in the postoperative period. Patients were satisfied with the music listening program in both the preoperative (95.5%) and the postoperative (91.5%) periods. In the preoperative period, the most popular music genres were Disney songs (17.7%), classical music (11.6%), and the Piano Guys (7.5%). In the postoperative period, the most favorable music genres were classical music (26.3%), Disney songs (7.9%), and the Beatles (7.9%). This project suggests that music listening may be associated with patients' decreased anxiety and depression as measured by the three-level version of the EuroQol five-dimensional questionnaire questionnaire (P = .008).ConclusionsImplementation of a music listening program in perioperative settings is feasible and accepted well by patients as evidenced by the high satisfaction scores. The project addressed patients' satisfaction, anxiety, and depression before and after elective surgery. The findings suggest that music listening is a safe, inexpensive, and effective intervention in perioperative settings.     

In vitro and in vivo evaluation of heparin mediated growth factor release from tissue‐engineered constructs for anterior cruciate ligament reconstruction

Anterior cruciate ligament (ACL) rupture is a common injury often necessitating surgical treatment with graft reconstruction. Due to limitations associated with current graft options, there is interest in a tissue‐engineered substitute for use in ACL regeneration. While they represent an important step in translation to clinical practice, relatively few in vivo studies have been performed to evaluate tissue‐engineered ACL grafts. In the present study, we immobilized heparin onto electrospun polycaprolactone scaffolds as a means of incorporating basic fibroblast growth factor (bFGF) onto the scaffold. In vitro, we demonstrated that human foreskin fibroblasts (HFFs) cultured on bFGF‐coated scaffolds had significantly greater cell proliferation. In vivo, we implanted electrospun polycaprolactone grafts with and without bFGF into athymic rat knees. We analyzed the regenerated ACL using histological methods up to 16 weeks post‐implantation. Hematoxylin and eosin staining demonstrated infiltration of the grafts with cells, and picrosirius red staining demonstrated aligned collagen fibers. At 16 weeks postop, mechanical testing of the grafts demonstrated that the grafts had approximately 30% the maximum load to failure of the native ACL. However, there were no significant differences observed between the graft groups with or without heparin‐immobilized bFGF. While this study demonstrates the potential of a regenerative medicine approach to treatment of ACL rupture, it also demonstrates that in vitro results do not always predict what will occur in vivo. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:229–236, 2015.     

STEAP: a prostate-specific cell-surface antigen highly expressed in human prostate tumors

In search of novel genes expressed in metastatic prostate cancer, we subtracted cDNA isolated from benign prostatic hypertrophic tissue from cDNA isolated from a prostate cancer xenograft model that mimics advanced disease. One novel gene that is highly expressed in advanced prostate cancer encodes a 339-amino acid protein with six potential membrane-spanning regions flanked by hydrophilic amino- and carboxyl-terminal domains. This structure suggests a potential function as a channel or transporter protein. This gene, named STEAP for six-transmembrane epithelial antigen of the prostate, is expressed predominantly in human prostate tissue and is up-regulated in multiple cancer cell lines, including prostate, bladder, colon, ovarian, and Ewing sarcoma. Immunohistochemical analysis of clinical specimens demonstrates significant STEAP expression at the cell-cell junctions of the secretory epithelium of prostate and prostate cancer cells. Little to no staining was detected at the plasma membranes of normal, nonprostate human tissues, except for bladder tissue, which expressed low levels of STEAP at the cell membrane. Protein analysis located STEAP at the cell surface of prostate-cancer cell lines. Our results support STEAP as a cell-surface tumor-antigen target for prostate cancer therapy and diagnostic imaging.     

Actions of endothelin-1 on swine ovarian (granulosa) cells.

We have investigated the regulatory actions of endothelin-1 (ET-1) on inositol phosphate accumulation, cytosolic free Ca2+ ion concentrations ([Ca2+]i), and basal and FSH-stimulated progesterone and cAMP accumulation by swine granulosa cells in serum-free cultures. ET-1 induced a rapid stimulation of phosphoinositide hydrolysis in populations of granulosa cells, as inferred by the rapid appearance of soluble inositol polyphosphates in response to ET-1 exposure. At the single cell level, fura-2 videomicroscopy was used to measure [Ca2+]i in individual granulosa cells. We observed cell-cell variability in the threshold concentration of ET-1 required to induce a rise in [Ca2+]i. More than 75% of granulosa cells responded to maximal doses of ET-1. The following parameters of [Ca2+]i were influenced by ET-1 concentration: percentage of responding cells, lag time for the onset of response, amplitude, and kinetics of the response. Two types of ET-1-mediated [Ca2+]i rises were observed. One type exhibited rapid Ca2+ kinetics, reaching at least a 2-fold increase above basal (spike phase) within 1-10 sec and returning to a new steady state (plateau phase) 2 min after onset. The other mode of response had slower [Ca2+]i kinetics, in which 50 sec or more were required to double [Ca2+]i, which remained at this level throughout the observation period (2.5 min). These responses to ET-1 were specific and were not initiated by vasopressin or tumor necrosis factor-alpha. In cell population studies using monolayer cultures of swine granulosa cells, ET-1 inhibited FSH-stimulated accumulation of progesterone and cAMP. The ET-1-mediated inhibition of FSH-stimulated accumulation of progesterone required at least 4 h of ET-1 exposure. The ET-1-mediated inhibition of both the FSH-stimulated accumulation of progesterone and cAMP after 24-h incubation was mimicked by an activator of protein kinase-C, phorbol 12-myristate 13-acetate, but not by an inactive phorbol. These observations in either single cells or populations of swine ovarian (granulosa) cells are consistent with a possible regulatory role of an ET-1-activated intracellular signaling pathway involving inositol phosphates, [Ca2+]i, and protein kinase-C in the mammalian granulosa cell.     

Inhibition of translation by poliovirus: inactivation of a specific initiation factor.

Translation of vesicular stomatitis virus (VSV) mRNA, like host mRNA translation, is inhibited in cells infected with poliovirus. To study the mechanism of poliovirus-induced inhibition of protein synthesis, we prepared extracts from poliovirus-infected and uninfected HeLa cells. Poliovirus mRNA was translated in lysates from both infected and uninfected cells, while VSV mRNA was translated only in the lysate from uninfected cells. Addition of purified translation initiation factors to the extract from infected cells showed that one factor, eIF-4B, could restore VSV mRNA translation in the infected lysate, but did not increase poliovirus mRNA translation. Further experiments involving translation of VSV mRNA in mixed extracts from poliovirus-infected and uninfected cells showed (i) that there was not an excess of an inhibitor of VSV mRNA translation in the infected lysate, but (ii) that an acitivity that caused a slow inactivation of eIF-4B was present in the infected lysate. Inactivation of eIF-4B appears to be the mechanism by which poliovirus infection causes a selective inhibition of translation.     

Multiple Genetic Mutations Associated with Polymyxin Resistance in Acinetobacter baumannii

We studied polymyxin B resistance in 10 pairs of clinical Acinetobacter baumannii isolates, two of which had developed polymyxin B resistance in vivo. All polymyxin B-resistant isolates had lower growth rates than and substitution mutations in the lpx or pmrB gene compared to their parent isolates. There were significant differences in terms of antibiotic susceptibility and genetic determinants of resistance in A. baumannii isolates that had developed polymyxin B resistance in vivo compared to isolates that had developed polymyxin B resistance in vitro.