Poor Placement Research Articles

A trick for visualisation of the radial tuberosity in a biceps tendon repair

The modified Henry approach to a biceps tendon repair allows a direct approach to the radial tuberosity although clear visualisation of it from this approach is difficult. It is particularly important to visualise the radial tuberosity well in order to avoid poor placement of the bone anchors, with the potential to give poor function of the biceps tendon. We have found using a Killian nasal speculum (Fig 1) allows excellent visualisation of the radial tuberosity while avoiding damage to surrounding structures (Fig 2). The radial tuberosity is directly visualised, minimising any risk of incorrect placement of drill holes for the anchor sutures.

What are reasonable expectations? Healthcare student perceptions of their programmes in the North West of England

Concerns about current levels of attrition from some healthcare programmes have emphasised the need to gain a greater insight into students' expectations and experiences. The aim of this study was to determine how students in the North West of England perceived their studies and to identify the factors that could contribute to students' dissatisfaction. A mixed methods sequential exploratory study. Nine universities in the North West of England. Phase one used narrative interviews with a purposive sample of 24 students to investigate their expectations and experiences. Data from these interviews were analysed using a thematic framework and direct quotes from key themes were incorporated into online survey for phase 2. Survey respondents were asked to rate their agreement to statements on a four-point Likert-type response format. There was also an opportunity to leave comments through open questions relating to each theme. A total of 1080 respondents completed the online survey in phase 2. The majority of students reported positive experiences of their course. There was strong agreement in the importance of the role of the personal tutor and of a supportive placement mentor. Some students indicated that the workload and academic level were a shock at first. Students identified difficulties around the cost of placement travel and the impact of placements on family life. Financial hardship was a frequently cited issue that students attributed to thoughts of discontinuation. Most students had positive learning experiences which meet their expectations. Students who have unmet expectations report poor placement experiences, lack of support, unexpectedly high workloads and financial difficulties. Clear guidance on the role of personal tutor and placement mentor is recommended.

Stereotactic Placement of Ventricular Catheters: Does It Affect Proximal Malfunction Rates?

Background: The majority of ventriculoperitoneal (VP) shunt malfunctions are due to proximal catheter failure. Ideal placement of Ommaya reservoirs is desired to avoid toxicity from intraparenchymal chemotherapy infusion. Objective: To determine whether stereotactic placement of ventricular catheters decreases the rate of Ommaya reservoir complications and the rate of proximal VP shunt failure. Methods: Under institutional review board approval, areview of a prospectively collected database was doneidentifying all patients who underwent stereotactic-guided placement of VP shunts and Ommaya reservoirs performed by a single surgeon between November 2007 and November 2009. Neuronavigation was used to preset a surgical plan consisting of an ideal entry point (usually frontal) and target point (ipsilateral foramen of Monro). The navigation probe was passed along this trajectory. After removal of the navigation probe, pre-sized ventricular catheters were passed without a stylet along the created path. Post-operative CT scans and clinical follow-up were assessed. Results: 70 patients (mean age 44.6 years) underwent 52 VP shunt and 18 Ommaya reservoir placement procedures. Rigid cranial fixation was used in all cases. All catheters were placed in a single pass. Mean operative time was 62 min. Mean follow-up was 16.3 months. No proximal malfunctions or Ommaya complications have been seen thus far. One patient required repositioning of an Ommaya reservoir as post-operative CT showed poor placement (1.4%). One patient with hydrocephalus due to cryptococcal meningitis developed an abdominal abscess and required removal of his entire shunt with subsequent replacement. One patient was noted to have a small amount of intraventricular hemorrhage; this did not result in any clinical change and did not require any further intervention. No other surgical complications were noted. Conclusion: In terms of results corroborating decreased proximal malfunction rates, we present the largest series of stereotactic-guided ventricular catheter placements to date. Though time in the operating room is increased due to navigation registration, actual operative time is comparable to procedures without navigation. A longer-term follow-up is needed to assess the longevity of our positive short-term results.

Minimally Invasive Cervical Spine Foraminotomy and Lateral Mass Screw Placement

This technique article describes accomplishing multilevel posterior cervical decompression and lateral mass screw placement through a tubular retraction system. Multilevel foraminotomy and instrumented fusion using lateral mass screw fixation can be achieved through a minimally invasive technique using specialized retractors and intraoperative fluoroscopic imaging. Minimally invasive surgical techniques have been adapted to the cervical spine with good results. These techniques have the theoretical advantages of reducing morbidity, blood loss, perioperative pain, and length of hospital stay associated with conventional open posterior spinal exposure. Minimally invasive access to the posterior cervical spine was performed with exposure through a paramedian muscle-splitting approach. With the assistance of a specialized tubular retraction system with a deep soft tissue expansion mechanism, multilevel posterior cervical decompression and fusion can be accomplished. Minimized access to perform multilevel posterior cervical foraminotomy and fusion can be safely accomplished with tubular retraction systems. Complications associated with these techniques can include inadequate decompression, improper instrumentation placement, or neurologic injury due to poor access and visualization. Multilevel foraminotomy and instrumented fusion using lateral mass screw fixation can be safely achieved using these techniques. Complications associated with these strategies are typically due to inadequate visualization, incomplete decompression, or poor placement of instrumentation. As with all minimally invasive spine techniques, the surgeon must ensure that goals of the surgery, both technical and clinical outcomes, are comparable to those of a conventional open procedure.

Strengthening of Slab Action in Transverse Direction of Damaged Deck of Prestressed Box Girder Bridge

The deck slab of a prestressed concrete (PSC) box girder bridge serves as an integral part of the structural box section, and any damage to the deck may seriously affect the load-resistance mechanism of the bridge. This paper discusses a case study of a PSC box girder that developed early damage to the deck because of the poor placement of concrete at the time of construction as established by in situ non- destructive and core tests. The possibility of total replacement of the top deck was ruled out because of the disruptive and tedious nature of the process, which could have endangered the overall stability of the box girder. Strengthening of the deck was performed by installing a series ofsteeljoistsattheundersideofthedeckslabandaddingathinoverlayofconcreteatthetoptorestoreittotherequisitestrength.Thisapproach was bestsuited, foritnotonlyimprovedthestressdistributioninthedeck,butalsomaintainedtheoriginalloadresistancemechanism provided by the prestressing arrangement in thegirder. The presented scheme was easy to implement and could beused for similar damages occurring to the deck of PSC box girder bridges. DOI: 10.1061/(ASCE)BE.1943-5592.0000318. © 2013 American Society of Civil Engineers. CE Database subject headings: Rehabilitation; Bridge decks; Prestressing; Box girders; Case studies. Author keywords: Rehabilitation; Bridge deck; Prestressed; Box girder.

Minimally Invasive Techniques for the Posterior Cervical Spine: Foraminal Decompression and Instrumented Fusion

Minimally invasive surgical techniques have been adopted to treat conditions in the posterior cervical spine. Through specialized tubular retraction systems and proper technique, multilevel posterior cervical foraminal decompression and instrumented fusion can be accomplished though a single incision. In this report we describe the techniques to perform both cervical foraminotomy and lateral mass fixation at 3 or more levels through an expanding tubular retractor. Complications may include inadequate decompression, poor placement of instrumentation, neurologic injury, or iatrogenic postoperative instability. Preoperative planning and careful technique can help avoid specific complications related to tubular access and poor visualization. The surgeon must always be prepared to convert to a traditional open procedure if an adequate decompression and/or fusion cannot be performed because of difficulties related to visualization, distorted anatomy, or improper access.

Cache index-aware memory allocation

Poor placement of data blocks in memory may negatively impact application performance because of an increase in the cache conflict miss rate [18]. For dynamically allocated structures this placement is typically determined by the memory allocator. Cache index-oblivious allocators may inadvertently place blocks on a restricted fraction of the available cache indexes, artificially and needlessly increasing the conflict miss rate. While some allocators are less vulnerable to this phenomena, no general-purpose malloc allocator is index-aware and methodologically addresses this concern. We demonstrate that many existing state-of-the-art allocators are index-oblivious, admitting performance pathologies for certain block sizes. We show that a simple adjustment within the allocator to control the spacing of blocks can provide better index coverage, which in turn reduces the superfluous conflict miss rate in various applications, improving performance with no observed negative consequences. The result is an index-aware allocator . Our technique is general and can easily be applied to most memory allocators and to various processor architectures. Furthermore, we can reduce inter-thread and inter-process conflict misses for processors where threads concurrently share the level-1 cache such as the Sun UltraSPARC-T2 ™ and Intel "Nehalem" by coloring the placement of blocks so that allocations for different threads and processes start on different cache indexes.

Padronização cirúrgica das abdominoplastias em âncora pós-gastroplastia

INTRODUCAO: Os autores propoem alteracoes na tecnica empregada nas dermolipectomias abdominais apos cirurgia bariatrica, com o intuito de corrigir imperfeicoes nos resultados obtidos com a padronizacao classica (i.e. resseccao de pele em bloco com manutencao da cicatriz umbilical). METODO: Sessenta e sete pacientes ex-obesos foram submetidos a dermolipectomia abdominal em âncora com resseccao parcelada de pele (primeiro o fuso vertical e apos o excesso horizontal), confeccao de neoumbigo e dermolipectomia pubiana associada. RESULTADOS: A nova padronizacao adotada permitiu reduzir as insatisfacoes previamente observadas, com melhor posicionamento da cicatriz horizontal e menor tensao na interseccao das cicatrizes. CONCLUSAO: A nova sistematizacao facilitou a marcacao pre-operatoria e permitiu refinar alguns aspectos que se mostravam insatisfatorios na experiencia com estes casos.

Essure Perforation and Chronic Pelvic Pain

Hysterosalpingography confirmed bilateral tubal occlusion, while showing the left microinsert in an abnormal configuration (Arrow). Transcervical (hysteroscopic) sterilization with Essure has become a common technique for permanent sterilization that is rapidly replacing traditional laparoscopic sterilization [1]. Performance of hysteroscopic sterilization in the office setting has been shown to be safe and feasible, with obvious advantages over laparoscopic sterilization with the patient under general anesthesia [2–7]. Evaluation of the Food and Drug Administration’s Manufacturer and User Facility Device Experience (MAUDE), which is a voluntary reporting database, revealed 20 reports released between January 2004 and January 2009 of pelvic pain requiring treatment after Essure placement. Most cases were related to poor placement. In 5 cases, the pain was attributed to a malpositioned device without perforation, and in 5 others, unilateral or bilateral cornual perforation was noted [8]. Other cases of tubal or cornual perforation with the Essure microinserts are reported in the literature [9,10]. Confirmation of tubal occlusion through hysterosalpingography (HSG) 3 months after insertion is still required per device labeling. Incorrect positioning of Essure has been associated with tubal patency on the 3-month HSG [11]. However, evidence of tubal occlusion on HSG does not necessarily rule out perforation or malposition. We present the case of a 37-year-old woman G4P2022 who presented with chronic pelvic pain for 1 year. The pain started after uncomplicated hysteroscopic sterilization with Essure by her primary gynecologist. The patient denied any history of pelvic pain before Essure placement. She had been on oral contraceptives (OCPs) for 10 years before Essure placement but decided to stop OCPs after a new diagnosis of

Microbiological quality of water from hand-dug wells used for domestic purposes in urban communities in Kumasi, Ghana

Assessment was done on the microbiological quality of water in hand-dug wells in urban communities in Kumasi, Ghana. A total of 256 water samples were taken from eight wells and examined for faecal coliforms, enterococci and helminths. High contamination levels were recorded in the wells, more so in the wet season, with faecal coliforms levels between 6.44 and 10.19 log units and faecal enterococci between 4.23 and 4.85 CFU per 100 ml. Influence on protection and lining of wells on water quality was not pronounced but mechanization reduced contamination significantly by about 3 log units. This study shows a stronger influence of poor sanitation and improper placement of wells on water quality compared to improvements made from lining and protection of wells. In the race to increase access to drinking water in poor urban settlements, quality of groundwater could be a major barrier, if provision of drinking water is not matched with improvements in sanitation and urban planning.

Young Investigator Abstract Session

Young Investigator Abstract Session

Contribution of computer‐assisted surgery in total wrist prosthesis: a comparative preliminary study of eight cases

The outcome of total wrist prostheses is disappointing due to complications, mainly loosening or absence of osseointegration. The main reason is poor placement. The aim of this study was to examine whether computer-assisted surgery (CAS) was advantageous in wrist prosthesis implantation. Our study group comprised eight patients. Group I was operated on with CAS and Group II without. In both groups, we used the RE-MOTION PGT prosthesis. In Group I, we used a navigation system to navigate the guide pin and K-wire of the radial component. The evaluation consisted of measuring the operating time, intra-operative stability and mobility and orientation of the prosthetic components on X-rays. The operating time was increased by 34 min with CAS. Intra-operative mobility in the two groups was comparable. There was no difference between the two groups with regard to the position of prosthetic components, except for the lateral view of the radial component. Our results show that CAS could improve placement of total wrist prostheses. All that is left to be done is to convince industrialists to invest in navigation systems dedicated to small joints.

Preliminary Findings at a Late Old Kingdom Fort in South Sinai, Including the Pottery, from the 2008 Season

The 2008 excavations at Ras Budran continued exposing the late Old Kingdom fort’s courtyard, finding baking installations, deep hollows filled by ash and sand, and parts of an underlying occupation layer that may reflect earlier activity at the fort (which needs further clarification). The exploration of a suggestive “chamber” in the eastern enclosure wall revealed it to be a modern disturbance. The project also concentrated on the western “bastion,” tracing it for 20 meters and finding evidence for salt encrustations and potential storm activity along the fort’s western side; one preliminary conclusion is that the sealing of the fort’s original entryway, and the subsequent abandonment and dismantling of the fort, may have been encouraged by a poor placement of the fort too close to the Red Sea and/or possibly increasingly harsher (winter) weather ca. 2300–2200 B.C. The study also contains Rexine Hummel’s analysis of the fort’s pottery fabrics, forms, and functions.

Trials and tribulations of clinical research teaching and training

Clinical research institutions have mushroomed in the country, though there is a generalized lack of experienced faculty. These institutes mostly confine themselves to theoretical aspects of clinical research, since there is lack of facilities for practical training. Students passing out of these institutes often find it difficult to get decent jobs and salaries at the entry level in the industry are poor. Poor placements of graduating students become major barriers for attracting quality students to the courses. This in turn affects the quality of people that the industry requires, in order to ensure a high growth rate of the industry. The industry, in addition to facing a severe crunch of high quality professionals, is also suffering from attrition that is a common feature. This attrition stems from, inter alia the industry’s demand for experienced people at the entry level. To improve overall standards of professionals entering clinical research, institutes and the industry need to get together and work in close co-operation. The industry and the institutes need to take positive steps if recent trends have to be reversed and clinical research as a whole has to move to a higher level. This article is based on the perceptions of the author, about the problems faced and offers some suggestions. Though these perceptions represent the reality, it is difficult to provide hard evidence that they do so.

Intraosseous ultrasonography to determine the accuracy of drill hole positioning prior to the placement of pedicle screws: an experimental study

Dorsal fixation with rods and pedicle screws (PSs) is the most frequently used surgery to correct traumatic and degenerative instabilities of the human spine. Prior to screw placement, screw holes are drilled along the vertebral pedicles. Despite the use of a variety of techniques, misplacement of screw holes, and consequently of the PSs, is a common problem. The authors investigated the usefulness of an intraspinal, intraosseous ultrasonography technique to determine the accuracy of drill hole positioning. An endovascular ultrasound transducer was used for the intraluminal scanning of bore holes in trabecular bovine bone, 12 pedicle drill holes in cadaveric human spine, and 4 pedicle drill holes in a patient undergoing thoracic spondylodesis. Seven of the experimental bore holes in the cadaveric spine were placed optimally (that is, inside the pedicle) and 5 were placed suboptimally (breaching the medial or lateral cortical surface of the pedicle). Computed tomography scans were obtained in the patient and cadaveric specimen after the procedure. The image quality achieved in examinations of native bovine bone tissue, the formalin-fixed human spine specimen, and human vertebrae in vivo was equal. The authors endosonographically identified correct intrapedicular and intravertebral positions as well as poor (cortex breached) placement of drill holes. Intraosseous ultrasonography is a promising technique for the investigation of PS holes prior to screw implantation, and may add to the safety of PS placement.

Temporary orthodontic anchorage devices for improving occlusion

The objective of the study was to provide insight into clinical and laboratory aspects of mini-screw implant (MI) research conducted in the Department of Orthodontics at Baylor College of Dentistry. Excerpts were selected from clinical and laboratory MI research utilizing one type of implant and one consistent placement protocol to illustrate the clinical usage of MI as skeletal anchorage during Class II bimaxillary correction. In addition, a translational animal model was utilized to illustrate possible side-effects of MI placement. Our studies have shown that successful and consistent clinical results are possible with MI use. Although iatrogenic trauma may occur during the placement of MI, a translational research model has provided data used to develop a placement protocol in order to avoid this dilemma. Absolute skeletal anchorage is a reality with MI use and can be used for successful orthodontic outcomes in the correction of Class II bimaxillary protrusion malocclusions to ideal Class I occlusions. Moreover, meticulous care has been shown to be essential with treatment planning and during placement of MI. Significant and extensive damage can occur with poor placement while healing is possible following minor trauma.

Bioactive titanium calcium phosphate coating for disc arthroplasty: analysis of 58 vertebral end plates after 6- to 12-month implantation

Background context From a biomechanical perspective, the successful outcome of total disc replacement is largely based on the mechanisms of acute fixation obtained at the index procedure and the extent of porous biological osseointegration at the prosthesis-bone interface, ensuring long-term device fixation. Purpose The present retrospective investigation quantifies the extent of porous osseointegration in cervical and lumbar disc arthroplasty implants containing a bioactive titanium/calcium phosphate coating. Study design Based on radiographic analysis and quantitative histomorphometry, the study was designed to determine the extent of porous osseointegration and whether osseointegration was affected by arthroplasty implant position. Outcome measures Quantitative histomorphometric analysis of trabecular apposition in metallic backed cervical and lumbar arthroplasty devices. Methods Twenty-nine disc arthroplasty devices underwent radiographic and histomorphometric analysis after 6- to 12-month implantation. The specimens included 12 cervical porous-coated motion devices implanted in a caprine model, and 17 lumbar Charité devices implanted in a non-human primate baboon. The two prosthetic-bone surfaces (superior and inferior) of each implant were examined for a total of 58 vertebral end plates. The operative motion segments were processed using undecalcified histologic technique with production of high-resolution light photomicrographs and microradiographs used for histomorphometric quantification of trabecular bone area at the implant interface. Based on plain film radiographs and histologic microradiographs, the technical accuracy of implant placement was classified as Ideal, Suboptimal, or Poor, with alignment referenced to the sagittal and coronal planes. Results The technical accuracy of implant placement in the cervical spine based on histologic microradiographs ranged from poor=8% (2 out of 24), suboptimal=17% (4 out of 24), to ideal=75% (18 out of 24), whereas accuracy of lumbar disc arthroplasty ranged from poor=20% (7 out of 34), suboptimal=52% (18 out of 34), and ideal=26% (9 out of 34). Based on histomorphometric analysis of the inferior and superior end plate surfaces, the trabecular apposition ranged from poor placement 21%±30% ingrowth, suboptimal 26%±33%, to ideal=44%±23% (p>.05). Similar findings were observed for the lumbar region; however, the suboptimal and ideal positions were closer in values with regard to trabecular apposition. Poor placement was 34%±29%, suboptimal 49%±19%, and ideal 51%±13%, but this was not statistically significant (p>.05). Conclusions The present study represents the largest analysis to date of any retrieved porous ingrowth disc replacement prostheses. A trend was observed of increase porous osseointegration with improved implant positioning; however, the small sample size and high standard deviations account for lack of statistical significance. Although osseointegration occurs despite nonideal intraoperative positioning, it remains imperative that surgeons strive for Ideal implant position.

Insertion of the Artificial Disc Replacement

Comparison of total disc replacement (TDR) with and without computer-assisted surgical navigation. To test and evaluate the accuracy of computer-assisted navigation for the lumbar spine by comparing the traditional C-arm-aided insertion of an arthroplasty device to the navigation-aided insertion of the implant. Previous studies have shown that poor placement of the CHARITE disc can be correlated to worse clinical results. Because of parallax effect, exclusive use of fluoroscopy could make placement of the artificial disc less accurate. False positioning may also lead to spondylolisthesis, disc degeneration of the adjacent segment, subsidence of the disc, and failure of the implant. Ten human cadaver spine specimens were used at 3 lumbar segments (L3-L4, L4-L5, and L5-S1). Before implantation, all artificial discs were planned for "ideal" placement on a digital computed tomography image. Fifteen lumbar intervertebral disc prostheses (Depuy, Raynham, MA) were placed using Vector Vision image guidance (BrainLAB AG, Munich, Germany), by an inexperienced TDR-surgeon. Fifteen lumbar intervertebral disc prostheses were placed with exclusive use of fluoroscopy by an experienced TDR-surgeon. After insertion, DICOM computed tomography scans were analyzed using computer software to assess placement accuracy of each disc prosthesis. The navigated placement of the disc was significantly more accurate. Only 3 navigated disc prostheses were suboptimal and none was poorly placed. Surgical computer-assisted navigation may be a useful tool in the hands of a spine surgeon to achieve more accurate placement of the disc prosthesis. Because of the parallax effect, computer-assisted navigation offers more placement accuracy than stan- dard fluoroscopy. Because the accurate placement of total disc prosthesis has been correlated with better clinical outcome, further study regarding the navigation of the TDR is essential.

Effectiveness of Pillar palatal implants for snoring management

Determine patient factors associated with the success and complications of using the Pillar palatal implants for snoring management. Retrospective series of 79 consecutive adult patients receiving Pillar implants for snoring management between January 2005 and December 2007. Multiple regression analysis was used to determine factors associated with initial and final bed partner satisfaction with the snoring result, and factors associated with Pillar-related complications. A total of 64 of 79 (81%) bed partners reported snoring improvement in patients after initial Pillar implantation; however, only 31 (39%) were satisfied with the level of reduction. Following secondary procedures, the number of satisfied bed partners improved to 52 (66%). Factors associated with final bed partner satisfaction included lower initial apnea-hypopnea index (AHI) (P = 0.029), Friedman tongue position I or II (P = 0.008), and shorter follow-up time (P = 0.001). Sixteen patients (20%) experienced procedure-related complications. Factors associated with Pillar complications included female gender (P = 0.001) and placement under general anesthesia (P = 0.009). Initial AHI values and tongue position scores are important determinants of final snoring success. Pillar implants placed in women and under general anesthesia may have a higher risk of poor placement and extrusion.

Effectiveness of Pillar Implants in Snoring Management

Objective Determine the effectiveness and complications of Pillar implants for snoring management in the course of routine clinical practice. Methods Retrospective series of adult patients receiving Pillar implants for snoring management between January 2005 and December 2007. Outcomes include procedure-related complications and patient satisfaction with snoring control. Results A total of 58 males and 12 females with an average age of 56 years (range, 33 to 74 years) underwent placement of Pillar implants for socially disruptive snoring. 21 patients were snorers, whereas 49 had mild to moderate degrees of sleep apnea. 41 patients were treated with 3 implants, and 24 patients received 4 or more implants. The procedure was performed in the outpatient setting in 47 cases and in the operating room in 23 cases. Complications included poor placement requiring removal (5 patients), and implant extrusion (4 patients). Complications were more common with implants placed in the OR, compared to the outpatient office (p=0.004). Of the patients with sufficient 3-month follow-up, 35/54 (65%) reported reduction in snoring, however only 28/54 (52%) were completely satisfied with the level of snoring reduction. When the satisfied patients were compared to dissatisfied patients, there were no noted differences in mean age, diagnosis of OSA, the use of adjunctive nasal surgery, or the number of implants placed. Conclusions Pillar implants offer satisfactory snoring reduction in approximately 50% of patients. Additional study is needed to determine factors that increase the probability of success. Implants placed under general anesthesia have a higher risk of poor placement and extrusion.