Influence de la morphologie sacro-pelvienne dans l'évolution du spondylolisthesis L5-S1 développemental

La spondylolyse et le spondylolisthésis sont une déformité bien connue dans le domaine de l’orthopédie. Par contre, il persiste des confusions et des débats sur différents aspects de cette pathologie incluant l’étiologie, l’histoire naturelle et le traitement. Récemment, deux études ont démontré l’influence significative de la morphologie du sacrum dans le spondylolisthésis par Inoue et al. et Whitesides et al.4,5 Ces trouvailles ont renouvelé l’intérêt dans l’évaluation radiologique de la balance sagittale de cette condition. L’objectif principal de ce travail est d’évaluer l’influence de la forme et l’orientation du sacrum chez les patients atteints de spondylolisthésis. Pour ce faire, nous avons construit une base de données de patients présentant un spondylolisthésis et d’un groupe contrôle. Par la suite les radiographies de ces sujets ont été analysées par un programme d’ordinateur afin de calculer tous les paramètres pertinents. Ce travail nous a tout d’abord permis de déterminer à partir des radiographies de 120 volontaires pédiatriques et plus de 130 patients pédiatriques atteints de la spondylolisthésis, les valeurs moyennes et la variation des paramètres angulaires qui influencent l’équilibre sagittal du rachis. Cette base de données est la première existante dans la population pédiatrique. Ces données seront d’une grande utilité pour le futur lors d’études concernant diverses conditions spinales. Nous avons remarqué une différence significative de la morphologie sacrée chez les sujets présentant le spondylolisthésis. Par ailleurs, l’étude de corrélation nous a également permis d’établir une forte relation entre le sacrum, le bassin et la colonne dans le profil sagittal. Finalement, ce travail a permis une meilleure compréhension globale de la posture sagittale chez les sujets normaux et chez les sujets atteints du spondylolisthésis qui pourra servir pour mieux analyser cette condition et pour ajuster les traitements selon l’analyse.

Spondylolisthésis, morphologie et orientation sacro-pelviennes chez une population de jeunes gymnastes

De multiples études ont rapporté une prévalence augmentée de spondylolyse et de spondylolisthésis chez certains groupes d’athlètes, en particulier les gymnastes, pouvant atteindre jusqu’à 40 à 50%. À cela s’ajoute le fait que plusieurs études récentes ont démontré une association entre le spondylolisthésis et une morphologie et orientation sacro-pelviennes déviante de la normale. La morphologie et l’orientation sacro-pelviennes chez les gymnastes ainsi que leur relation avec le spondylolisthésis n’ont jamais été analysées. L’objectif de cette étude était donc d’évaluer la prévalence du spondylolithésis au sein d’une cohorte de gymnastes ainsi que les caractéristiques démographiques et paramètres de morphologie et orientation sacro-pelviennes associés. Afin d’atteindre cet objectif, une évaluation des caractéristiques démographiques et des paramètres radiologiques d’une cohorte de 92 jeunes gymnastes a été menée. Les deux études présentées ont démontré une prévalence de spondylolisthésis chez les jeunes gymnastes de 6.5%, similaire à celle retrouvée dans la population générale. Le nombre d’heures d’entraînement hebdomadaire a été le seul facteur statistiquement différents entre les gymnastes avec et ceux sans spondylolisthésis. Nos résultats ont aussi démontré que les gymnastes atteints d’un spondylolisthésis présentent une morphologie et une orientation sacro-pelviennes sagittales différentes, en terme d’incidence pelvienne (p = 0.02) et d’angle de table sacrée (p = 0.036), de celles des gymnastes sans spondylolisthésis. Nos observations supportent donc l’importance du rôle de la morphologie et de l’orientation sacro-pelviennes dans le développement du spondylolisthésis.

Minimal-invasive percutaneous reduction and transsacral screw fixation for U-shaped fractures

STUDY DESIGN Technical note and case series. OBJECTIVE To introduce an innovative minimal-invasive surgical procedure reducing surgery time and blood loss in management of U-shaped sacrum fractures. SUMMARY OF BACKGROUND Despite their seldom appearance, U-shaped fractures can cause severe neurological deficits and surgical management difficulties. According to the nature of the injury normally occurring in multi-injured patients after a fall from height, a jump, or road traffic accident, U-shaped fractures create a spinopelvic dissociation and hence are highly unstable. In the past, time-consuming open procedures like large posterior constructs or shortening osteotomies with or without decompression were the method of choice, sacrificing spinal mobility. Insufficient restoration of sacrococcygeal angle and pelvic incidence with conventional techniques may have adverse long-term effects in these patients. METHODS In a consecutive series of 3 patients, percutaneous reduction of the fracture with Schanz pins inserted in either the pedicles of L5 or the S1 body and the posterior superior iliac crest was achieved. The Schanz pins act as lever, allowing a good manipulation of the fracture. The reduction is secured by a temporary external fixator to permit optimal restoration of pelvic incidence and sacral kyphosis. Insertion of 2 transsacral screws allow fixation of the restored spinopelvic alignment. RESULTS Anatomic alignment of the sacrum was possible in each case. Surgery time ranged from 90 to 155 minutes and the blood loss was <50 mL in all 3 cases. Two patients had very good results in the long term regarding maintenance of pelvic incidence and sacrococcygeal angle. One patient with previous cauda equina decompression had loss of correction after 6 months. CONCLUSIONS Percutaneous reduction and transsacral screw fixation offers a less invasive method for treating U-shaped fractures. This can be advantageous in treatment of patients with multiple injuries.

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.

The Effects of Postural Loading, Sacral Orientation, and Age on Sex Differences in Lumbar Functional Morphology and Health

Thesis (Ph.D.)--University of Washington, 2016-06

THE INCIDENCE OF PELVIC ENDOMETRIOSIS IN ROCHESTER, MINNESOTA, 1970-1979

The primary objectives of the study were to measure the incidence of pelvic endometriosis among white females of reproductive age (15-49 years) in Rochester, Minnesota, during the period 1970-1979 and to determine the risk of endometriosis by age, marital status, nun status, and educational attainment in this population. An historical prospective design was used. Incident (newly diagnosed) cases were identified from community medical records, and person-years of risk in the study population were estimated from census data.^ Almost two-thirds of the incident cases had surgically verified endometriosis, while the remainder were diagnosed by clinical findings alone. Incidence rates were prepared first with histologically confirmed cases only and then with the successive inclusion of less certain cases: surgically visualized, clinically probable, and clinically possible. On this basis, overall incidence rates were 108.8 to 246.9 newly diagnosed cases per 100,000 person-years. The incidence of pelvic endometriosis was lowest for women 15-19 years of age, increased markedly through age 44, and then declined for women 45-49 years of age. A significantly greater risk of pelvic endometriosis in never married women was detected only when the numerator was limited to histologically confirmed cases. Among never married women 20-49 years of age, no significant difference in the risk of pelvic endometriosis by nun status was detected, but a trend toward a lower incidence in nuns was observed. Women with education beyond high school had a significantly higher incidence of endometriosis than women with less education.^ Cases in the four diagnostic groups differed greatly by age and marital status but were similar with respect to virtually all other characteristics, once age differences were considered. Reproductive history characteristics described included: age of menarche; history of menopause; total pregnancies; ages of first pregnancy, marriage, and sexual intercourse; years from menarche to first intercourse; years of ovulatory cycling; difficulty becoming pregnant; and delay of the first pregnancy by choice. How these characteristics of incident cases differ from those of women free of endometriosis needs to be studied in future research. ^

A Rare Abdomino-Pelvic Tumor: Paraganglioma

Paragangliomas are rare tumors, with a reported incidence of 2–8 per million. They are chromaffin cell tumors that develop from the neural crest cells and may be divided in tumors derived from the parasympathetic or sympathetic ganglia. We report a case a of a 32-year-old nulliparous woman, referred to our Infertility Clinic. Abdomino-pelvic ultrasound identified a large abdominopelvic tumor, without ovarian origin (both ovaries were identified and had normal morphology). Magnetic Resonance Imaging suggested a right adnexal multicystic, vascularized mass close to iliac vessels and questioning an ovarian origin. At exploratory laparotomy, a 10 cm encapsulated and vascularized mass was found beginning just below right renal artery and extending to the level of the broad ligament. This mass was totally excised and histopathology was consistent with Paraganglioma.

Treatments for invasive carcinoma of the cervix: What are their impacts on the pelvic floor functions?

Aims: Describe the impact of surgery, radiotherapy and chemoradiation in the pelvic floor functions in cervical cancer patients. Materials and Methods: A prospective study with women submitted to radical hysterectomy (RH) (n = 20),exclusive radiotherapy (RT) (n= 20)or chemoradiation (CT/RT)(n = 20)for invasive cervical cancer. Urinary, intestinal and sexual function, as well as vaginal length and pelvic floor musclecontraction were evaluated. Comparisons between groups were performed by Kruskal-Wallis and Chi-square tests (p < 0.05). Results: The groups were similar in stress urinary incontinence incidence (p = 0.56), urinary urgency (p = 0.44),urge incontinence (p = 0.54),nocturia(p = 0.53), incomplete bowel emptying (p = 0.76),bowel urgency(p = 0.12)and soilage(p = 0.43). The CT/ RT group presented a higher urinary frequency(p < 0.001)and diarrhea(p = 0.025). Patients in the RH group were more sexually active(p = 0.01) and experienced less dyspareunia (p = 0.021). Vaginal length was shorter in RT group (5.5 ± 1.9 cm) and CT/ RT(.3 ± 1.5 cm) than in the RH group (7.4 ± 1.1 cm) (p < 0.001). Pelvic floor muscle contraction was similar (p = 0.302). Conclusions: RT and CT/RT treatment for cervical carcinoma are more associated to sexual and intestinal dysfunctions.

Timing of progression from Chlamydia trachomatis infection to pelvic inflammatory disease: a mathematical modelling study

Background Pelvic inflammatory disease (PID) results from the ascending spread of microorganisms from the vagina and endocervix to the upper genital tract. PID can lead to infertility, ectopic pregnancy and chronic pelvic pain. The timing of development of PID after the sexually transmitted bacterial infection Chlamydia trachomatis (chlamydia) might affect the impact of screening interventions, but is currently unknown. This study investigates three hypothetical processes for the timing of progression: at the start, at the end, or throughout the duration of chlamydia infection. Methods We develop a compartmental model that describes the trial structure of a published randomised controlled trial (RCT) and allows each of the three processes to be examined using the same model structure. The RCT estimated the effect of a single chlamydia screening test on the cumulative incidence of PID up to one year later. The fraction of chlamydia infected women who progress to PID is obtained for each hypothetical process by the maximum likelihood method using the results of the RCT. Results The predicted cumulative incidence of PID cases from all causes after one year depends on the fraction of chlamydia infected women that progresses to PID and on the type of progression. Progression at a constant rate from a chlamydia infection to PID or at the end of the infection was compatible with the findings of the RCT. The corresponding estimated fraction of chlamydia infected women that develops PID is 10% (95% confidence interval 7-13%) in both processes. Conclusions The findings of this study suggest that clinical PID can occur throughout the course of a chlamydia infection, which will leave a window of opportunity for screening to prevent PID.

Is Pelvic Lymph Node Dissection Necessary in Patients with a Serum PSA<10ng/ml Undergoing Radical Prostatectomy for Prostate Cancer?

OBJECTIVE: Controversy persists concerning the role of pelvic lymph node dissection (PLND) in patients with preoperative PSA values <10ng/ml undergoing treatment for prostate cancer with a curative intent. The aim of this study was to determine the incidence of lymph node metastasis in this subgroup of patients. METHODS: Patients with clinically localized prostate cancer and a serum PSA<10ng/ml, without neoadjuvant hormonal or radiotherapy, with negative staging examinations who underwent radical retropubic prostatectomy with bilateral extended PLND and with >/=10 lymph nodes detected by the pathologist in the surgical specimen, were included in the study. RESULTS: A total of 231 patients with a median serum PSA of 6.7ng/ml (range 0.4-9.98) and a median age of 62 years (range 44-76) were evaluated. A median of 20 (range 10-72) nodes were removed per patient. Positive nodes were found in 26 of 231 patients (11%), the majority of which (81%) had a Gleason score >/=7 in the surgical specimen. Of the patients with a Gleason score >/=7 in the prostatectomy specimen 25% had positive nodes, whereas only 3% with a Gleason score incidence of positive nodes in patients with clinically localized prostate cancer, a serum PSA<10ng/ml and a Gleason score >/=7 in the prostatectomy specimen was 25% after extended PLND. It seems that in this patient group extended PLND, including removal of nodes along the internal iliac vessels, is warranted.

Incidence of severe reproductive tract complications associated with diagnosed genital chlamydial infection: the Uppsala Women's Cohort Study

OBJECTIVE: To estimate the cumulative incidence of severe complications associated with genital chlamydia infection in the general female population. METHODS: The Uppsala Women's Cohort Study was a retrospective population based cohort study in Sweden, linking laboratory, hospital, and population registers. We estimated the cumulative incidence of hospital diagnosed pelvic inflammatory disease, ectopic pregnancy, and infertility, and used multivariable regression models to estimate hazard ratios according to screening status. RESULTS: We analysed complete data from 43 715 women in Uppsala aged 15-24 years between January 1985 and December 1989. Follow up until the end of 1999 included 709 000 woman years and 3025 events. The cumulative incidence of pelvic inflammatory disease by age 35 years was 3.9% (95% CI 3.7% to 4.0%) overall: 5.6% (4.7% to 6.7%) in women who ever tested positive for chlamydia, 4.0% (3.7% to 4.4%) in those with negative tests, and 2.9% (2.7% to 3.2%) in those who were never screened. The corresponding figures were: for ectopic pregnancy, 2.3% (2.2% to 2.5%) overall, 2.7% (2.1% to 3.5%), 2.0% (1.8% to 2.3%), and 1.9% (1.7% to 2.1%); and for infertility, 4.1% (3.9% to 4.3%) overall, 6.7% (5.7% to 7.9%), 4.7% (4.4% to 5.1%), and 3.1% (2.8% to 3.3%). Low educational attainment was strongly associated with the development of all outcomes. CONCLUSIONS: The incidence of severe chlamydia associated complications estimated from ours, and other population based studies, was lower than expected. Studies that incorporate data about pelvic inflammatory disease diagnosed in primary care and behavioural risk factors would further improve our understanding of the natural history of chlamydia. Our results provide reassurance for patients, but mean that the benefits of chlamydia screening programmes might have been overestimated.

Outcome after radical cystectomy with limited or extended pelvic lymph node dissection

PURPOSE: We compared recurrence patterns and survival of patients with urothelial bladder cancer undergoing radical cystectomy who either had limited or extended pelvic lymph node dissection at 2 institutions between 1987 and 2000. MATERIALS AND METHODS: Two consecutive series of patients treated with radical cystectomy and limited pelvic lymph node dissection (336; Cleveland Clinic) and extended pelvic lymph node dissection (322; University of Bern) were analyzed. All cases were staged N0M0 prior to radical cystectomy, and none were treated with neoadjuvant radiotherapy or chemotherapy. Patients with PTis/pT1 and pT4 disease were excluded from analysis. Pathological characteristics based on the 1997 TNM system and recurrence patterns were determined. RESULTS: The overall lymph node positive rate was 13% for patients with limited and 26% for those who had extended pelvic lymph node dissection. The 5-year recurrence-free survival of patients with lymph node positive disease was 7% for limited and 35% for extended pelvic lymph node dissection. The 5-year recurrence-free survival for pT2pN0 cases was 67% for limited and 77% for extended pelvic lymph node dissection, and the respective percentages for pT3pN0 cases were 23% and 57% (p <0.0001). The 5-year recurrence-free survival for pT2pN0-2 cases was 63% for limited and 71% for extended pelvic lymph node dissection, and for pT3pN0-2 cases the respective figures were 19% and 49% (p <0.0001). Incidence of local and systemic failure correlated closely with pathological stage for both series. CONCLUSIONS: Our data suggest that limited pelvic lymph node dissection is associated with suboptimal staging, poorer outcome for patients with node positive and node negative disease, and a higher rate of local progression. Extended pelvic lymph node dissection allows for more accurate staging and improved survival of patients with nonorgan confined and lymph node positive disease.

What are predictors for patients' quality of life after pelvic ring fractures?

Background Our knowledge of factors influencing mortality of patients with pelvic ring injuries and the impact of associated injuries is currently based on limited information. Questions/purposes Weidentified the (1) causes and time of death, (2) demography, and (3) pattern and severity of injuries in patients with pelvic ring fractures who did not survive. Methods We prospectively collected data on 5340 patients listed in the German Pelvic Trauma Registry between April 30, 2004 and July 29, 2011; 3034 of 5340 (57%) patientswere female. Demographic data and parameters indicating the type and severity of injury were recorded for patients who died in hospital (nonsurvivors) and compared with data of patients who survived (survivors). The median followup was 13 days (range, 0–1117 days). Results A total of 238 (4%) patients died a median of 2 days after trauma. The main cause of death was massive bleeding (34%), predominantly from the pelvic region (62% of all patients who died because of massive bleeding). Fifty six percent of nonsurvivors and 43% of survivors were male. Nonsurvivors were characterized by a higher incidence of complex pelvic injuries (32% versus 8%), less isolated pelvic ring fractures (13% versus 49%), lower initial blood hemoglobin concentration (6.7 ± 2.9 versus 9.8 ± 3.0 g/dL) and systolic arterial blood pressure (77 ± 27 versus 106 ± 24 mmHg), and higher injury severity score (ISS) (35 ± 16 versus 15 ± 12). Conclusion Patients with pelvic fractures who did not survive were characterized by male gender, severe multiple trauma, and major hemorrhage.

Emergency stabilization of the pelvic ring: Clinical comparison between three different techniques

Background: Emergency devices for pelvic ring stabilization include circumferential sheets, pelvic binders, and c-clamps. Our knowledge of the outcome of these techniques is currently based on limited information. Methods: Using the dataset of the German Pelvic Trauma Registry, demographic and injury-associated characteristics as well as the outcome of pelvic fracture patients after sheet, binder, and c-clamp treatment was compared. Outcome parameters included transfusion requirement of packed red blood cells, length of hospital stay, mortality, and incidence of lethal pelvic bleeding. Results: Two hundred seven of 6137 (3.4%) patients documented in the German Pelvic Trauma Registry between April 30th 2004 and January 19th 2012 were treated by sheets, binders, or c-clamps. In most cases, c-clamps (69%) were used, followed by sheets (16%), and binders (15%). The median age was significantly lower in patients treated with binders than in patients treated with sheets or c-clamps (26 vs. 47 vs. 42 years, p = 0.01). Sheet wrapping was associated with a significantly higher incidence of lethal pelvic bleeding compared to binder or c-clamp stabilization (23% vs. 4% vs. 8%). No significant differences between the study groups were found in sex, fracture type, blood haemoglobin concentration, arterial blood pressure, Injury Severity Score, the incidence of additional pelvic packing and arterial embolization, need of red blood cell transfusion, length of hospitalisation, and mortality. Conclusions: The data suggest that emergency stabilization of the pelvic ring by binders and c-clamps is associated with a lower incidence of lethal pelvic bleeding compared to sheet wrapping.

Sample size considerations using mathematical models: an example with Chlamydia trachomatis infection and its sequelae pelvic inflammatory disease.

BACKGROUND The success of an intervention to prevent the complications of an infection is influenced by the natural history of the infection. Assumptions about the temporal relationship between infection and the development of sequelae can affect the predicted effect size of an intervention and the sample size calculation. This study investigates how a mathematical model can be used to inform sample size calculations for a randomised controlled trial (RCT) using the example of Chlamydia trachomatis infection and pelvic inflammatory disease (PID). METHODS We used a compartmental model to imitate the structure of a published RCT. We considered three different processes for the timing of PID development, in relation to the initial C. trachomatis infection: immediate, constant throughout, or at the end of the infectious period. For each process we assumed that, of all women infected, the same fraction would develop PID in the absence of an intervention. We examined two sets of assumptions used to calculate the sample size in a published RCT that investigated the effect of chlamydia screening on PID incidence. We also investigated the influence of the natural history parameters of chlamydia on the required sample size. RESULTS The assumed event rates and effect sizes used for the sample size calculation implicitly determined the temporal relationship between chlamydia infection and PID in the model. Even small changes in the assumed PID incidence and relative risk (RR) led to considerable differences in the hypothesised mechanism of PID development. The RR and the sample size needed per group also depend on the natural history parameters of chlamydia. CONCLUSIONS Mathematical modelling helps to understand the temporal relationship between an infection and its sequelae and can show how uncertainties about natural history parameters affect sample size calculations when planning a RCT.