Haematuria in two geldings caused by osteochondroma of the os pubis: Case reports and anatomic study of the os pubis in 41 cadaveric pelvises

Exostosis of the os pubis causing haematuria, and potentially cystorrhexis, in horses has not been described in the literature. In this study, 2 geldings that suffered from exercise-induced haematuria caused by an osteochondroma of the os pubis, and the assessment of 41 cadaveric pubic bones are reported on. The anatomy of the os pubis is highly variable. The prevalence of exostosis in the os pubis appears to be higher in male horses. Palpation and ultrasonography of the pelvis per rectum and cystoscopy are valuable diagnostic tools. Depending on the extent of changes in the bladder wall, surgical removal of the exostosis should be considered in order to prevent cystorrhexis. In horses that present with haematuria, closer assessment of the os pubis for the presence of an exostosis is warranted.

Preparing medical students for normal birth: an interactive workshop by pre-registration midwifery students.

There is an increasing recognition of the need to improve inter professional relationships within clinical practice (DoH, 2001). Evidence supports the assertion that health care professionals who are able to communicate and work effectively together and who have a mutual respect and understanding for one another’s roles will provide a higher standard of care (McPherson et al, 2001; Begley, 2008). Providing inter professional education within a University setting offers an opportunity for a non-threatening learning environment where students can develop confidence and build collaborative working relationships with one another (Saxell et al, 2009).
An inter-professional education initiative was developed in Queen’s University Belfast within the Schools of Nursing and Midwifery and Medicine and piloted in 2014. The aim of the collaboration was to introduce concepts of normal labour and birth to fourth year medical students prior to their obstetric and gynaecological placement in hospital. The teaching staff felt this would be an excellent opportunity for final year pre-registration midwifery students to demonstrate their knowledge and understanding on normality in labour and birth by preparing interactive workshops with the medical students. The midwifery students were provided with an outline agenda in relation to content for the workshop, but then were allowed creative licence with regard to delivery of the workshop. The workshops consisted of approximately 4 midwifery students to 12 medical students. Resources such as birthing balls, birth mannequins, dolls and pelvises were available to the students to increase interactivity. Significant emphasis was placed upon the importance of relationship building with women in labour and the concept of being ‘with woman’ was core to all elements of teaching. Midwifery students undertook acting roles such as the labouring woman, partner or a midwife role and acted out mini scenarios such as contacting for advice about early labour; positions for labour or positions for birth. Medical students were prompted to vocalise about their feelings towards labour and birth and encouraged to think about their role within the birth setting.
Preliminary evaluations of the workshops have been extremely positive from both the midwifery students and the medical students. The midwifery students have commented on the enjoyable aspects of team working for preparing for the workshop and also the confidence gained from teaching the medical students. The medical students have evaluated the teaching by the midwifery students positively and felt that it lowered their anxiety going into the labour setting. A number of midwifery and medical students have subsequently worked with one another within the practice setting which has been recognised as beneficial. Both Schools have recognised the benefits of this form of inter professional education and have subsequently made a commitment to embed it within each curriculum.

Iliac osteosynthesis with nylon clamp associated to polymethylmethacrylate bone cement - experimental study in dogs cadavers

Fractures of iliac body are generally consequences of traumas of great impact. These fractures lead to a lack of locomotor response and in specific cases, surgery is needed. Among the possible therapeutic lines, implants become a good option. In this paper, the authors used dog corpses to develop a surgery technique of iliac osteosynthesis, employing nylon clamps and bone cement of polymethylmethacrylate (PMMA). Sixteen hemi pelvises of eight dog corpses, which had its iliac bodies totally fractured previously, were utilized. The osteosynthesis was reached through the implantation of six nylon clamps, distributed equally between the bone fragments. With the use of the nylon clamps there were bone realignment and a contact surface to fixation of the biomaterial. The technique developed in corpses was easily executed, effective in reduction, alignment and stabilization of the fracture. The authors suggest more studies in vitro to evaluate immobilization resistance and functionality in dogs with this condition.

PS-GANS: A Patient-Specific, Gravity Assisted Navigation System for Acetabular Cup Placement

In this paper we propose a new system that allows reliable acetabular cup placement when the THA is operated in lateral approach. Conceptually it combines the accuracy of computer-generated patient-specific morphology information with an easy-to-use mechanical guide, which effectively uses natural gravity as the angular reference. The former is achieved by using a statistical shape model-based 2D-3D reconstruction technique that can generate a scaled, patient-specific 3D shape model of the pelvis from a single conventional anteroposterior (AP) pelvic X-ray radiograph. The reconstructed 3D shape model facilitates a reliable and accurate co-registration of the mechanical guide with the patient’s anatomy in the operating theater. We validated the accuracy of our system by conducting experiments on placing seven cups to four pelvises with different morphologies. Taking the measurements from an image-free navigation system as the ground truth, our system showed an average accuracy of 2.1 ±0.7 o for inclination and an average accuracy of 1.2 ±1.4 o for anteversion.

Anteroposterior pelvic radiographs to assess acetabular retroversion: high validity of the "cross-over-sign"

Acetabular retroversion has been proposed to contribute to the development of osteoarthritis of the hip. For the diagnosis of this condition, conventional AP pelvic radiographs may represent a reliable, easily available diagnostic modality as they can be obtained with a reproducible technique allowing the anterior and posterior acetabular rims to be visible for assessment. This study was designed to: (i) determine cranial, central, and caudal anatomic acetabular version (AV) from cadaveric specimens; (ii) establish the validity and reliability of the radiographic measurements of central acetabular anteversion; and (iii) determine the validity and reliability of the radiographic "cross-over-sign" to detect acetabular retroversion. Using 43 desiccated pelvises (86 acetabuli) the anatomic AVs were measured at three different transverse planes (cranially, centrally, and caudally). From these pelvises, standardized AP pelvic radiographs were obtained. To directly measure central AV, a modified radiographic method is introduced for the use of AP pelvic radiographs. The validity and reliability of this radiographic method and of the radiographic cross-over-sign to detect cranial acetabular retroversion were determined. The mean central and caudal anatomic AVs were approximately 20 degrees , and the mean cranial AV was 8 degrees . Cranial retroversion (AV < 0 degrees ) was present in 19 of 86 hips (22%). A linear correlation was found between the central and cranial AV. Below 10 degrees of central AV, all acetabuli were cranially retroverted. Between 10 degrees and 20 degrees , 30% of the acetabuli were cranially retroverted, and above 20 degrees , only 1 of 45 acetabuli was cranially retroverted. The radiographic measurement of the central AV (20.3 +/- 6.5 degrees ) correlated strongly with the anatomic AV (20.1 +/- 6.4 degrees ). The sensitivity of the cross-over-sign to detect a cranial acetabular anteversion of less than 4 degrees was 96%, its specificity 95%, and the positive predictive and negative predictive values 90% and 98%, respectively. Both the modified radiographic anteversion measurements and the cross-over-sign demonstrated substantial inter- and intraobserver reliability. Retroversion is almost exclusively a problem of the cranial acetabulum. The cranial AV is on average 12 degrees lower than the central AV, with the latter directly measurable from AP pelvic radiographs. A central AV of less than 10 degrees was associated with cranial retroversion. The presence of a positive cross-over-sign is a highly reliable indicator of cranial AV of <4 degrees.

Comparative Evaluation of Pelvic Allograft Selection Methods

This paper presents a firsthand comparative evaluation of three different existing methods for selecting a suitable allograft from a bone storage bank. The three examined methods are manual selection, automatic volume-based registration, and automatic surface-based registration. Although the methods were originally published for different bones, they were adapted to be systematically applied on the same data set of hemi-pelvises. A thorough experiment was designed and applied in order to highlight the advantages and disadvantages of each method. The methods were applied on the whole pelvis and on smaller fragments, thus producing a realistic set of clinical scenarios. Clinically relevant criteria are used for the assessment such as surface distances and the quality of the junctions between the donor and the receptor. The obtained results showed that both automatic methods outperform the manual counterpart. Additional advantages of the surface-based method are in the lower computational time requirements and the greater contact surfaces where the donor meets the recipient.

Percutaneous screw fixation of the iliosacral joint: optimal screw pathways are frequently not completely intraosseous

INTRODUCTION In iliosacral screw fixation, the dimensions of solely intraosseous (secure) pathways, perpendicular to the ilio-sacral articulation (optimal) with corresponding entry (EP) and aiming points (AP) on lateral fluoroscopic projections, and the factors (demographic, anatomic) influencing these have not yet been described. METHODS In 100 CTs of normal pelvises, the height and width of the secure and optimal pathways were measured on axial and coronal views bilaterally (total measurements: n=200). Corresponding EP and AP were defined as either the location of the screw head or tip at the crossing of lateral innominate bones' cortices (EP) and sacral midlines (AP) within the centre of the pathway, respectively. EP and AP were transferred to the sagittal pelvic view using a coordinate system with the zero-point in the centre of the posterior cortex of the S1 vertebral body (x-axis parallel to upper S1 endplate). Distances are expressed in relation to the anteroposterior distance of the S1 upper endplate (in %). The influence of demographic (age, gender, side) and/or anatomic (PIA=pelvic incidence angle; TCA=transversal curvature angle, PID-Index=pelvic incidence distance-index; USW=unilateral sacral width-index) parameters on pathway dimensions and positions of EP and AP were assessed (multivariate analysis). RESULTS The width, height or both factors of the pathways were at least 7mm or more in 32% and 53% or 20%, respectively. The EP was on average 14±24% behind the centre of the posterior S1 cortex and 41±14% below it. The AP was on average 53±7% in the front of the centre of the posterior S1 cortex and 11±7% above it. PIA influenced the width, TCA, PID-Index the height of the pathways. PIA, PID-Index, and USW-Index significantly influenced EP and AP. Age, gender, and TCA significantly influenced EP. CONCLUSION Secure and optimal placement of screws of at least 7mm in diameter will be unfeasible in the majority of patients. Thoughtful preoperative planning of screw placement on CT scans is advisable to identify secure pathways with an optimal direction. For this purpose, the presented methodology of determining and transferring EPs and APs of corresponding pathways to the sagittal pelvic view using a coordinate system may be useful.

Injury study of the femur-pelvic complex in automobile crash environment. Final report.

National Highway Traffic Safety Administration, Washington, D.C.