Surgeons Plan Research Articles

Describing Crouzon and Pfeiffer syndrome based on principal component analysis

Crouzon and Pfeiffer syndrome are syndromic craniosynostosis caused by specific mutations in the FGFR genes. Patients share the characteristics of a tall, flattened forehead, exorbitism, hypertelorism, maxillary hypoplasia and mandibular prognathism. Geometric morphometrics allows the identification of the global shape changes within and between the normal and syndromic population. MethodsData from 27 Crouzon-Pfeiffer and 33 normal subjects were landmarked in order to compare both populations. With principal component analysis the variation within both groups was visualized and the vector of change was calculated. This model normalized a Crouzon-Pfeiffer skull and was compared to age-matched normative control data. ResultsPCA defined a vector that described the shape changes between both populations. Movies showed how the normal skull transformed into a Crouzon-Pfeiffer phenotype and vice versa. Comparing these results to established age-matched normal control data confirmed that our model could normalize a Crouzon-Pfeiffer skull. ConclusionsPCA was able to describe deformities associated with Crouzon-Pfeiffer syndrome and is a promising method to analyse variability in syndromic craniosynostosis. The virtual normalization of a Crouzon-Pfeiffer skull is useful to delineate the phenotypic changes required for correction, can help surgeons plan reconstructive surgery and is a potentially promising surgical outcome measure.

A rule-based algorithm can output valid surgical strategies in the treatment of AIS.

Variability in surgical strategies for the treatment of adolescent idiopathic scoliosis (AIS) has been demonstrated despite the existence of classifications to guide selection of AIS curves to include in fusion. Decision trees and rule-based algorithms have demonstrated their potential to improve reliability of AIS classification because of their systematic approach and they have also been proposed in algorithms for selection of instrumentation levels in scoliosis. Our working hypothesis is that a rule-based algorithm with a knowledge base extracted from the literature can efficiently output surgical strategies alternatives for a given AIS case. Our objective is to develop a rule-based algorithm based on peer-reviewed literature to output alternative surgical strategies for approach and levels of fusion. A literature search of all English Manuscripts published between 2000 and December 2009 with Pubmed and Google scholar electronic search using the following keywords: "adolescent idiopathic scoliosis" and "surgery" alternatively with "levels of fusion" or "approach". All returned abstracts were screened for contents that could contain rules to include in the knowledge base. A dataset of 1,556 AIS cases treated surgically was used to test the surgical strategy rule-based algorithm (SSRBA) and evaluate how many surgical treatments are covered by the algorithm. The SSRBA was programmed using Matlab. Descriptive statistic was used to evaluate the ability of the rule-based algorithm to cover all treatment alternatives. A SSRBA was successfully developed following Lenke classification's concept that the spine is divided into three curve segments [proximal thoracic (PT), main thoracic (MT) and thoracolumbar/lumbar (TL)]. Each of the 1,556 AIS patients in the dataset was ran through the SSRBA. It proposed an average of 3.78 (±2.06) surgical strategies per case. Overall, the SSRBA is able to match the treatment offered by the surgeon in approach and level of fusion 70% of the time (with one vertebral level leeway). This study is to the author's knowledge the first attempt at proposing an algorithm to output all surgical alternatives for a given AIS case. It uses a rule-based algorithm with a knowledge base extracted from peer-reviewed literature in an area with great variability. When tested against a database of AIS patients treated surgically, the SSRBA developed has the ability to propose a surgical plan with respect to approach and levels of fusion that match the surgeon's plan in a great majority of cases. Since this SSRBA seems to output multiple valid surgical strategies, it could allow the comparisons of various strategies and the outcomes achieved in similar cases in large databases for a given case and guide surgical treatment.

Repair of combined cheek and nose defects: categorization and utilization.

Combined cheek and nose soft tissue defects can represent a formidable challenge to the reconstructive surgeon. It is important for the surgeon to think of these defects as four separate categories: cheek with nasal sidewall, cheek with nasal sidewall and exposed bone, cheek with nasal sidewall plus ala, and cheek with simple posterior ala defect. This categorization will help the surgeon plan the repair and provide a successful aesthetic outcome. There are multiple repair options that the surgeon can use, and the surgeon should be facile with all types. It is universally agreed that the cheek defect must be repaired prior to undertaking the repair of the nasal defect.

Patient-specific total knee arthroplasty: the importance of planning by the surgeon

The purpose of the study was to evaluate the accuracy of the planning of the patient-specific pin guides in total knee arthroplasty (TKA). This planning was performed primarily by a technician of the company and offered to the surgeon. All parameters of the implantation can either be modified or accepted by the surgeon. The hypothesis was that the plan needs preoperative intervention by the surgeon. A prospective study in 50 patients was carried out. All patients received the same posterior-stabilised implant with patient-specific instrumentation. All surgical parameters (coronal, sagittal, rotational alignment, femoral and tibial resection levels and implant sizes) were checked by the orthopaedic surgeon and changed if necessary. Preoperatively, the femoral size was changed in 8 patients (16 %), the femoral flexion in 23 patients (46 %), the femoral shift in 34 patients (68 %), the tibial size in 24 patients (48 %) and the tibial rotation in all patients. The epicondylar axis was accepted in 47 patients (94 %) in the technician plan. Mean planning time was 8 ± 4 min. Intraoperatively, the femoral anterior-posterior size was in 50 patients (100 %) the same as in the surgeon and in 42 patients (84 %) the same as in the technician plan (p = 0.003). The tibial component implanted was in 42 patients (84 %) the same as in the surgeon and in 19 patients (38 %) the same as in the technician plan (p < 0.0001). A femoral distal recut was necessary in 31 patients (62 %) and a change of the tibial proximal cut in 17 patients (34 %) during surgery. Intraoperatively, no changes of the femoral and tibial alignment, the femoral anterior-posterior size, the femoral flexion, the femoral shift, the femoral and tibial rotation were necessary. Postoperatively, the coronal mechanical overall axis was within ±3° in 47 patients (94 %) with a maximum deviation of 5.6°. Significant changes of the technician plan were necessary to get an accurate preoperative plan. Intraoperative changes were significant less compared to the surgeon than to the technician plan. No major changes (alignment, femoral anterior-posterior size and rotation) of the surgeon plan were necessary. Surgeons using patient-specific pin guides in TKA may verify the default plan provided by the technician. A blind reply on the technician plan may be not recommended. Therapeutic study, Level III.

Editor’s Spotlight/Take 5: Orthopaedic Surgeons Frequently Underestimate the Cost of Orthopaedic Implants (DOI 10.1007/s11999-012-2757-x)

Editor’s Spotlight/Take 5: Orthopaedic Surgeons Frequently Underestimate the Cost of Orthopaedic Implants (DOI 10.1007/s11999-012-2757-x)

Setting Time Comparison of Four Antimicrobial Laden Calcium Sulfate Plasters

ABSTRACT Background The surgeon may implant calcium sulfate pellets (aka gypsum) as a resorbable antimicrobial vehicle at the surgical site in severe cases of osteomyelitis. Gypsum setting times with or without antibiotic additives are found scattered throughout the literature, but often factors known to alter setting time are either not disclosed or not held constant between experiments. To our knowledge, no prior study compares the setting time of calcium sulfate plaster mixed with the four commonly used antibiotics under constant conditions as presented here. Purpose To compare the setting times of calcium sulfate hemihydrate mixtures containing vancomycin, cefazolin, tobramycin, or amphotericin B. Materials and methods Groups consisted of samples comprised of 6.3 gm calcium sulfate hemihydrate (CSH) mixed with approximately 1/4th a vial of lyophilized antimicrobial (vancomycin, cefazolin, tobramycin or amphotericin B) with CSH powder to normal saline ratio of 1.7 gm/ml and mixed for 30 seconds at controlled speed and humidity. Each sample initial setting time (Ti) and final setting time (Tf) were established by Gillmore needles method according to ASTM standard C266- 08 apparatus specifications. Results Kruskal-Wallis one-way analysis of variance by ranks revealed that antibiotic type affected the initial and final setting times of gypsum (p &lt; 0.05). Post hoc analysis using Dunn's multiple comparisons indicated that there was no difference between control Ti (7.2 ± 1.1 min) and that of vancomycin or cefazolin group (9.8 ± 1.7 or 14.2 ± 1.3 min, respectively, p &gt; 0.05), but the Ti of the tobramycin and amphotericin B groups (31.8 ± 5.7 and 140.4 ± 18.0 min) differed from the control Ti (p &lt; 0.05). Likewise, there was no difference of control Tf (p &gt; 0.05, 12.2 ± 1.1 min) when compared to vancomycin or cefazolin groups (22.2 ± 6.9 or 25.7 ± 4.1 min), but that the Tf of tobramycin and amphotericin B groups (76.3 ± 5.9 and 200.0 ± 21.1 min) each differed from the control group (p &lt; 0.05). Conclusion This experiment is aimed to help surgeons plan when they should begin preparing their calcium sulfate antibiotic beads during surgery. As a general guideline, allow 15 minutes to set when adding a 1 gm vial of vancomycin or cefazolin, 30 minutes for adding a 1.2 gm vial tobramycin, and 2.5 hours for adding a 50 mg vial of amphotericin B. Kroger J, Beaufond P, Inceoglu S, Maskiewicz V, Cheng W, Brier-Jones JE. Setting Time Comparison of Four Antimicrobial Laden Calcium Sulfate Plasters. The Duke Orthop J 2013;3(1):36-40.

Can Hip Anatomy Be Reconstructed With Femoral Components Having Only One Neck Morphology? A Study on 466 Hips

This extensive radiographic study asks if there is a statistical relationship between the size of the stem that will best fit the femur and the vertical and lateral offsets of the reconstructed acetabular center, what is the distribution of vertical and lateral offsets in this large and if there is a statistical difference among surgeons in the planned location of the reconstructed acetabular center. On 466 radiographs, five surgeons separately templated stem size and acetabular cup location. The vertical and horizontal coordinates of the reconstructed acetabulum center were measured relative to the planned position of the stem. We found a strong correlation between the stem size and the average lateral and vertical offsets. Acetabular reaming associated with the anatomic variability of native femoral necks, leads to a span of 36mm in lateral offset, and a span of 39mm in vertical offset. Statistically significant differences were also found in the way surgeons plan acetabular reaming.

LinDOS: A Linear Distraction Osteogenesis Simulation System for Maxillofacial Surgery Based on FEM

Developmental craniofacial deformity often has serious infection on the patient's chewing, language ability, swallowing, breathing and other related functions. Currently, internal and linear Distraction Osteogenesis (DO) are main surgery solutions of bone transportation and recovery in clinic. In this paper, we present a computer system called LinDOS for maxillofacial system reconstruction and visualization, maxillofacial tissues stress distribution analysis, as well as linear distraction osteogenesis simulation. Both design architecture and the function modules of the system are described in detail. The system can be employed as an assistant tool of maxillofacial preoperative planning and postoperative prediction for maxillofacial surgeons.

An optimal design for patient‐specific templates for pedicle spine screws placement

Currently, pedicle screws are positioned using a free-hand technique or under fluoroscopic guidance, with error in the range 10-40%, depending on the skill of the surgeon. After spine CT acquisition, each vertebra is segmented and the surgeon plans screw positioning in a virtual environment, then the template is designed around the chosen trajectories. This design is based on surgical and mechanical considerations to obtain an optimal solution to guarantee template stability, simple positioning and minimized intervention invasiveness. In vitro evaluation on synthetic spine models and ex vivo animal tests on porcine specimens were performed, with the insertion of 28 Kirschner wires. During the in vitro tests, all the surgeons rendered positive evaluations regarding the device and considered template placement to be easy. Ex vivo tests were evaluated by CT examination, which showed that 96.5% of the Kirschner wires had been correctly inserted. The proposed solution is a promising, simple, highly precise, low-cost solution to safely performing posterior stabilization. Such a solution would be of interest even in hospitals in which a few spine interventions are performed per year, and for which it is not reasonable to purchase the equipment required for robotic or navigated approaches.

Thoracic Surgery Workforce: Report of STS/AATS Thoracic Surgery Practice and Access Task Force—Snapshot 2010

The Society of Thoracic Surgeons (STS) and the American Association for Thoracic Surgery (AATS) have intermittently surveyed their combined membership. These manpower surveys have provided snapshots of thoracic surgery, documenting practice changes over time. At this critical time in US health care reform the physician workforce is of critical importance. This survey updates the data obtained from the 2000 and 2005 surveys. The survey instrument was updated from the 2005 survey. It was received by 5,265 surgeon members of the STS/AATS during November and December 2009. There was a superb 50% return rate. The data were entered into a comprehensive database. Perception Solutions, Inc, independently performed the analysis. The median age of the active US thoracic surgeons is 52.9 years. Women comprise 3.4% of adult cardiac, 5.2% of congenital heart, and 7.9% of general thoracic surgeons. The decision to pursue a career in thoracic surgery was made before or in medical school by 45.3% of surgeons. The majority of survey respondents had a mean of 8.7 years of residency training after medical school graduation. The cumulative average educational debt was $56,000. Overall career satisfaction was 46% (very or extremely satisfied). Database participation was 84%. Operative volume over the past 12 months decreased for 30% of surgeons. Malpractice premiums have steadily increased over the past 5 years from $55,947 to $59,673. The number of additional years the currently active US cardiothoracic surgeon plans to practice is 12.6 years. Therefore, the projected retirement age of the thoracic surgery workforce will be 65. This is consistent among all surgeons: adult cardiac, 66 years; congenital heart, 65 years; and general thoracic, 67 years. These data give a clear profile of the specialty at this time. The major challenges remain length of training and educational debt of the thoracic surgeon. Case volume, scope of practice, malpractice costs, and career satisfaction remain major elements to provide a positive environment to recruit new surgeons in to the specialty. The resident pool has contracted while the workforce ages and retirement looms. Significant shortages may develop as the US population ages in the environment of health care reform.

Thoracic Surgery Workforce: Report of STS/AATS Thoracic Surgery Practice and Access Task Force—Snapshot 2010

The Society of Thoracic Surgeons (STS) and the American Association for Thoracic Surgery (AATS) have intermittently surveyed their combined membership. These manpower surveys have provided snapshots of thoracic surgery, documenting practice changes over time. At this critical time in US health care reform the physician workforce is of critical importance. This survey updates the data obtained from the 2000 and 2005 surveys. The survey instrument was updated from the 2005 survey. It was received by 5265 surgeon members of the STS/AATS during November and December 2009. There was a superb 50% return rate. The data were entered into a comprehensive database. Perception Solutions, Inc, independently performed the analysis. The median age of the active US thoracic surgeons is 52.9 years. Women comprise 3.4% of adult cardiac, 5.2% of congenital heart, and 7.9% of general thoracic surgeons. The decision to pursue a career in thoracic surgery was made before or in medical school by 45.3% of surgeons. The majority of survey respondents had a mean of 8.7 years of residency training after medical school graduation. The cumulative average educational debt was $56,000. Overall career satisfaction was 46% (very or extremely satisfied). Database participation was 84%. Operative volume over the past 12 months decreased for 30% of surgeons. Malpractice premiums have steadily increased over the past 5 years from $55,947 to $59,673. The number of additional years the currently active US cardiothoracic surgeon plans to practice is 12.6 years. Therefore, the projected retirement age of the thoracic surgery workforce will be 65. This is consistent among all surgeons: adult cardiac, 66 years; congenital heart, 65 years; and general thoracic, 67 years. These data give a clear profile of the specialty at this time. The major challenges remain length of training and educational debt of the thoracic surgeon. Case volume, scope of practice, malpractice costs, and career satisfaction remain major elements to provide a positive environment to recruit new surgeons in to the specialty. The resident pool has contracted while the workforce ages and retirement looms. Significant shortages may develop as the US population ages in the environment of health care reform.

Rapid Prototyping for Treatment of Cranial Reconstruction Surgery

Design methods for medical rapid prototyping (RP) of personalized cranioplasty implants are presented in this paper. RP offers an easier way to design customized implants and manufacture them within a very short period. Computed tomography (CT) scans were acquired on a General Electric CT scanner and converted to solid models using Mimics software from Materialise. Stereo lithography patterns were prototyped using Objet build style on a Eden 250.The models helped the surgeons plan and rehearse the surgery well in advance. RP biomedical model is greatly convenient to diagnosis and treatment planning. It could decrease the operation time and the risk of misinterpretation of the medical problem. A physical biomedical model also facilitates surgery planning and makes the rehearsal and simulation of the operation possibly.

Automated preoperative planning of femoral stem in total hip arthroplasty from 3D CT data: Atlas-based approach and comparative study

Atlas-based methods for automated preoperative planning of the femoral stem implant in total hip arthroplasty are described. Statistical atlases are constructed from a number of past preoperative plans prepared by experienced surgeons in order to represent the surgeon's expertise of the planning. Two types of atlases are considered. One is a statistical distance map atlas, which represents surgeon's preference of the contact pattern between the femoral canal (host bone) and stem (implant) surfaces. The other is an optimal reference plan, which is selected as the best representative plan expected to minimize the deviation from the surgeon's preferred contact pattern. These atlases are fitted to the patient data to automatically generate the preoperative plan of the femoral stem. In this paper, we formulate a general framework of atlas-based implant planning, and then describe the methods for construction and utilization of the two proposed atlases. In the experiments, we used 40 cases to evaluate the proposed methods and compare them with previous methods by defining the errors as differences between automated and surgeon's plans. By using the proposed methods, the positional and orientation errors were significantly reduced compared with the previous methods and the size error was superior to inter-surgeon variability in size selection using 2D templates on an X-ray image reported in previous work.

Value of chest CT in the diagnosis and management of tracheobronchial foreign bodies

The aim of the present study was to investigate the value of chest multidetector computed tomography (CT) in the evaluation of children with suspected foreign body aspiration. Chest CT was performed in 45 consecutive children with suspected foreign body aspiration, and plain chest X-ray was conducted at the same time. Multiplanar reformatted imaging was carried out after multidetector CT. Rigid bronchoscopy and removal of the foreign body was performed under general anesthesia. All 42 patients (100%) with tracheobronchial foreign bodies were identified on chest CT. Three patients avoided unnecessary operations due to negative CT scans. For the patients with tracheobronchial foreign bodies, the occurrence of unilateral hyperlucent lung and post-obstructive lobar or segmental infiltrates on plain chest X-ray was 42.9% (18/42) and 4.8% (2/42), respectively. Twenty-two of the 42 patients (52.4%) had no abnormalities on plain X-ray. The difference between multidetector CT and plain X-ray results was statistically significant (P < 0.001). Surgical plans were designed and appropriate foreign body forceps were selected based on the CT scans. All foreign bodies were removed successfully, and no severe complications were observed. The location, shape, and volume of the foreign bodies found at surgery were consistent with the CT images. The diagnosis of foreign body aspiration of the airway in children can be accomplished by using chest multidetector CT. It is often useful in delineating the exact shape, location, volume and form of a bronchial foreign body and can help the surgeon plan for operative bronchoscopy and safe removal of the foreign body.

Factors predictive of complex Mohs surgery cases

Background: Mohs surgery allows excision of skin cancer in a tissue-sparing fashion that minimizes recurrence risk. While the indications for Mohs surgery are well established, factors predictive of complex Mohs cases are less studied. Objective: To determine patient, tumor, and surgeon characteristics associated with complex Mohs cases. Methods: A retrospective review was performed for a 3-year period (7/2006–6/2009) to identify Mohs cases requiring ≥4 stages (“complex”), and a control population requiring ≤3 stages (“non-complex”). Surgical logs for four fellowship-trained Mohs surgeons were reviewed. Results: 77 complex cases (51 academic practice vs. 26 private practice) were compared with 154 control cases (102 academic practice vs. 52 private practice). There were no significant differences in patient age, gender, immunosuppression, academic (2.7% complex) versus private practice (3.5% complex), or surgeons' years of experience. Factors associated with complexity included: recurrent tumors (p < 0.001; odds ratio (OR) 6.88; 95% confidence interval (CI) 2.8–17); basal cell carcinoma (BCC) with infiltrative or morpheaform histology (p = 0.0019; OR 3.0; 95% CI 1.5–6.3); tumors of the nose (p = 0.0168; OR 2.05; 95% CI 1.1–3.7), especially nasal tip (p = 0.0103; OR 3.68; 95% CI 1.3–10.6) and ear (p = 0.0178; OR 3.0; 95% CI 1.2–7.9), especially helix (p = 0.00744; OR 5.9; 95% CI 1.5–22.7); tumors with pre-operative size >1 cm (p = 0.018; OR 2.0; 95% CI 1.1–3.6); and tumors involving >1 cosmetic subunit (p = 0.0072; OR 5.0; 95% CI 1.5–16.7). Complex tumors had greater post-operative area (10.6 ± 1.3 vs. 3.6 ± 0.7 cm2; p < 0.0001), and more often required flap/graft repair (p < 0.0001; OR 6.9; 95% CI 3.7–13.1). Limitations: A retrospective study representing a single geographic area. Conclusions: Mohs cases are similar in complexity whether in academic or private practice. Recurrent/aggressive histology tumors, tumors >1 cm, and tumors on the nose or ear are more likely to prove surgically complex. Advanced knowledge of these factors may be useful pre-operatively as Mohs surgeons plan their scheduled cases.

Predictors of outcome after elective endovascular abdominal aortic aneurysm repair and external validation of a risk prediction model

Endovascular abdominal aortic aneurysm (AAA) repair (EVAR) has been associated with lower operative mortality and morbidity than open surgery but comparable long-term mortality and higher delayed complication and reintervention rates. Attention has therefore been directed to identifying preoperative and operative variables that influence outcomes after EVAR. Risk-prediction models, such as the EVAR Risk Assessment (ERA) model, have also been developed to help surgeons plan EVAR procedures. The aims of this study were (1) to describe outcomes of elective EVAR at the Royal Brisbane and Women's Hospital (RBWH), (2) to identify preoperative and operative variables predictive of outcomes after EVAR, and (3) to externally validate the ERA model. All elective EVAR procedures at the RBWH before July 1, 2009, were reviewed. Descriptive analyses were performed to determine the outcomes. Univariate and multivariate analyses were performed to identify preoperative and operative variables predictive of outcomes after EVAR. Binomial logistic regression analyses were used to externally validate the ERA model. Before July 1, 2009, 197 patients (172 men), who were a mean age of 72.8 years, underwent elective EVAR at the RBWH. Operative mortality was 1.0%. Survival was 81.1% at 3 years and 63.2% at 5 years. Multivariate analysis showed predictors of survival were age (P = .0126), American Society of Anesthesiologists (ASA) score (P = .0180), and chronic obstructive pulmonary disease (P = .0348) at 3 years and age (P = .0103), ASA score (P = .0006), renal failure (P = .0048), and serum creatinine (P = .0022) at 5 years. Aortic branch vessel score was predictive of initial (30-day) type II endoleak (P = .0015). AAA tortuosity was predictive of midterm type I endoleak (P = .0251). Female sex was associated with lower rates of initial clinical success (P = .0406). The ERA model fitted RBWH data well for early death (C statistic = .906), 3-year survival (C statistic = .735), 5-year survival (C statistic = .800), and initial type I endoleak (C statistic = .850). The outcomes of elective EVAR at the RBWH are broadly consistent with those of a nationwide Australian audit and recent randomized trials. Age and ASA score are independent predictors of midterm survival after elective EVAR. The ERA model predicts mortality-related outcomes and initial type I endoleak well for RBWH elective EVAR patients.

Radiological evalution of civilian gunshot injuries in Nauth, Nnewi

This study is meant to evaluate Civilian gunshot injuries in the city of Nnewi with a view of finding the pattern of injuries and background ofaffected individual. It is also aimed to bring to the fore the fact that even our easily available plain radiographic studies will localize the pellets, identify some important damages caused by the pellets and help us in planning for management even in the absence of other complex radiological investigative modalities like computed Tomographic scanners, Magnetic Resonance Imaging (MRI), Angiographic studies and interventional techniques /procedures. All gunshot injuries investigated in the Department of Radiology, Nnamdi Azikiwe University Teaching Hospital, Nnewi (NAUTH) between December 1998 – April 2000 were qualified for this work. The films were reviewed as to location of the pellets to enable the surgeon plan for possible extraction. Twenty-five (25) such patients were reviewed in this study. This showed a male/female ratio of 8.1. The age range of subjects was between 18 – 65 years with a mean age of 35years. The model age involved was 20 – 30 years. The commonest site involved as shown by this study was the lower limb ( from pelvic 5 to the foot). The main source of referral was the Accident & Emergency Unit.

Adverse effects of preoperative steroid use on surgical outcomes

Background Preoperative steroid use has been associated with increased postoperative complications. We sought to establish these risks using data from the National Surgical Quality Improvement Program (NSQIP). Methods NSQIP public use files from 2005 to 2008 were analyzed for preoperative steroid use and postoperative adverse events. Results Of 635,265 patients identified, 20,434 (3.2%) used steroids preoperatively. Superficial surgical site infections (SSI) increased from 2.9% to 5% using steroids (odds ratio, 1.724). Deep SSIs increased from .8% to 1.8% (odds ratio, 2.353). Organ/space SSIs and dehiscence increased 2 to 3-fold with steroid use (odds ratios, 2.469 and 3.338, respectively). Mortality increased almost 4-fold (1.6% to 6.0%; odds ratio, 3.920). All results were significant ( P < .001). Conclusions Previous concerns related to surgical risks in patients on chronic steroid regimens appear valid. These results may assist in counceling patients regarding the increased risk of surgery. They may also help the surgeon plan and modify the procedure if possible.

Clinical value of chest CT in the diagnosis and management of tracheobronchial foreign bodies

Objective The purpose of this study was to investigate the value of chest CT in the evaluation ofchildren with suspected foreign body aspiration. Methods Chest CT was performed in 45consecutive children with suspected foreign body aspiration. The patients were examined with 16-slice Multidetector CT (MDCT) using 100 ～ 150 kV,30 ～ 50 mA, 1 mm section thickness. 1.2 pitch ratio, and 0.6 ～1.0 mm reconstruction interval. multiplanar reformatted (MPR) imaging were carried out after MDCT examinations. Results Chest CT revealed all foreign bodies in 42 of the 45 patients. Three patients with suspected foreign body aspiration did not show evidence of foreign body on CT,and they were treated with antibiotics for one week. These patients avoided unnecessary operations and recovered completely. The other 42 patients had evidence of foreign bodies in their bronchi. We designed the surgerical plan and selected appropriate foreign body forceps based on the CT scans. All of the foreign bodies were removed successfully, and no severe complications were observed. The location, shape, and volume of the foreign bodies found at surgery were consistent with the CT images. Conclusion The diagnosis of foreign body aspiration of the airwayin children can be accomplished by using chest CT. It is often useful in delineating the exact shape, location, volume and form of a bronchial foreign body and can help the surgeon plan for operative bronchoscopy and safe removal of the foreign body. Key words: Foreign body,aspiration ; Computerized tomography ; Rigid bronchoscopy ;

Uncemented custom femoral components in hip arthroplasty

Background and purpose We have developed an individually designed, uncemented femoral component for achievement of improved strain distribution and fixation to the bone, to make uncemented stems more applicable in femurs of abnormal size and shape, and to improve the joint mechanics. Here we describe the design of the implant and present the results of a prospective clinical study with at least 7 years of follow-up.Patients and methods The prostheses are produced by CAD-CAM technique. The design of the stem is based on CT information, and the neck design is based on the surgeon's planning of the center of rotation, femoral head offset, and leg length correction. The first-generation stem produced before 2001 had a proximal HA coating and a sand-blasted distal part that was down-scaled to avoid contact with compact bone. The second-generation stem had a porous coating beneath the HA layer and the distal part of the stem was polished.The implant was used in 762 hips (614 patients) from 1995 until 2009. 191 of these hips were followed for 7 years and 83 others were followed for 10 years, and these hips are included in the present study. Mean age at surgery was 48 (20–65) years. Congenital dysplasia of the hip was the reason for osteoarthritis in 46% and 57% of the hips in respective groups. Merle d'Aubigné score was recorded in 152 and 75 hips in the two groups. Prostheses followed for 10 years, and almost all in the 7-year group, were first-generation stems.Results The 7- and 10-year cumulative revision rates were 1.1% and 2.4%, respectively, with stem revision for any reason as endpoint. The clinical results were similar at 7 and 10 years, with Merle d'Aubigné scores of 17. Intraoperative trochanteric fissures occurred in 2 of the 191 operations (1.0%); both healed after wiring. In hips followed for 7 years, 2 periprosthetic fractures occurred; exchange of the stem was necessary in both. One additional fracture occurred between 7 and 10 years, and it was treated successfully with osteosynthesis. The rate of dislocation was 1.6% and 2.4%, respectively. There was no radiographic loosening at follow-up.Interpretation Use of a custom femoral stem gives a reliable fixation and promising medium-term clinical results in femurs of normal and abnormal shape and dimension. The individual design, which enables optimized joint mechanics, gives a low risk of mechanical complications.