Sacrococcygeal dimensions and curvature are associated with resection quality in rectal cancer excision.

BACKGROUND: Technical factors affect oncologic outcomes in rectal cancer surgery. The anatomy of the bony pelvis can affect technical aspects of surgery, but is seldom considered preoperatively. We performed a morphometric analysis of the bony pelvis in patients having rectal cancer resection to assess its effect on surgical specimen quality. METHODS: We performed a retrospective analysis of a prospectively maintained database of patients who had resection for rectal cancer from January 2014 to December 2017. Preoperative magnetic resonance imaging (MRI) and computed tomography (CT) images were accessed and measurements of sacrococcygeal distance, sacrococcygeal recess depth/area, sacrococcygeal angulation, anteroposterior pelvic inlet/outlet, pubic height and interspinous distance were made. Outcome measures included anatomical variation, operating time and mesorectal specimen grade. In patients having extra-levator abdominoperineal excision (eLAPE) with coccygectomy, the completeness of coccygeal resection was assessed by postoperative CT scan. Data were analysed using binomial and multinomial logistic regression and linear regression. RESULTS: One hundred and twenty-two consecutive rectal cancer resections were performed (39 open, 42 laparoscopic, 12 laparoscopic-converted and 29 robotic). The median age was 72 years (range: 29-88 years). The male:female ratio was 83:39. Eighty-one patients had anterior resection, 8 had low Hartmann's resection and 32 had APE. Of those who had APE, 21 had eLAPE (all with coccygectomy). Females had a larger pelvic inlet (female: 124.9 mm, male: 114.9 mm), interspinous diameter(female:112.8 mm, male:97.6 mm), sacrococcygeal depth (female:42.6 mm, 39.35 mm) and sacrococcygeal area recess than males (female: 3697 mm2, male: 3481.5 mm2). Males had a greater pubic height (female: 51.8 mm, male: 54.05 mm) and greater sacrococcygeal distance (female: 116.7 mm, male: 123.65 mm) than females. In patients having anterior resection, tumour distance from the anal verge (p = 0.004), sacrococcygeal distance (p = 0.006) and sacrococcygeal curvature (p = 0.002) were associated with specimen quality. In patients who had eLAPE, median preoperative coccygeal length was 41 mm (IQR: 35.1-45.5). The median length of coccygeal resection was 9 mm (IQR: 1-17.45 mm). The median length of coccyx remaining postoperatively was 33 mm (IQR: 21.35-39 mm). CONCLUSIONS: Sacrococcygeal curvature and distance as well as tumour distance from the anal margin were associated with specimen quality in anterior resection. Coccygectomy was not performed as completely as surgeons thought. Surgeons should include sacrococcygeal bony anatomy in rectal cancer surgical planning to potentially improve outcomes in both anterior resection and eLAPE approaches.

Are fibroid and bony pelvis characteristics associated with urinary and pelvic symptom severity?

BACKGROUND: Urinary and pelvic floor symptoms often are attributed to size and location of uterine fibroid tumors. However, direct supporting evidence that links increased size to worsening symptoms is scant and limited to ultrasound evaluation of fibroid tumors. Because management of fibroid tumors is targeted towards symptomatic relief, the identification of fibroid and pelvic characteristics that are associated with worse symptoms is vital to the optimization of therapies and prevention needless interventions. OBJECTIVE: We examined the correlation between urinary, pelvic floor and fibroid symptoms, and fibroid size and location using precise uterine fibroid and bony pelvis characteristics that were obtained from magnetic resonance imaging. STUDY DESIGN: A retrospective review (2013-2017) of a multidisciplinary fibroid clinic identified 338 women who had been examined via pelvic magnetic resonance imaging, Pelvic Floor Distress Inventory questionnaire (score 0-300), and a Uterine Fibroid Symptoms questionnaire (score 1-100). Multiple linear regression analysis was used to assess the influence of clinical factors and magnetic resonance imaging findings on scaled Pelvic Floor Distress Inventory and Uterine Fibroid Symptoms scores. Data were analyzed with statistical software. RESULTS: Our cohort of 338 women had a median Pelvic Floor Distress Inventory of 72.7 (interquartile range, 41-112.3). Increased Pelvic Floor Distress Inventory score was associated with clinical factors of higher body mass index (P<.001), noncommercial insurance (P<.001), increased parity (P=.001), and a history of incontinence surgery (P=.003). Uterine volume, dominant fibroid volume, dimension and location, and fibroid tumor location relative to the bony pelvis structure did not reach significance when compared with pelvic floor symptom severity. The mean Uterine Fibroid Symptoms score was 52.0 (standard deviation, 23.5). An increased Uterine Fibroid Symptoms score was associated with dominant submucosal fibroid tumors (P=.011), body mass index (P<.0016), and a clinical history of anemia (P<.001) or any hormonal treatment for fibroid tumors (P=.009). CONCLUSION: Contrary to common belief, in this cohort of women who sought fibroid care, size and position of fibroid tumors or uterus were not associated with pelvic floor symptom severity. Whereas, bleeding symptom severity was associated with dominant submucosal fibroid tumor and previous hormonal treatment. Careful attention to clinical factors such as body mass index and medical history is recommended when pelvic floor symptoms are evaluated in women with uterine fibroid tumors.

Analysis of Pelvic Fracture Healing Status in 198 Cases.

ABSTRACT: Objective To analyze the relationship between the number of pelvic ring fractures, the location of fracture and Tile type of pelvic fracture and pelvic fracture healing status. To discuss how to understand the pelvic malunion, severe pelvic malunion and bony pelvis deformity （destruction） in Classification of the Impairment Related to Injury. Methods One hundred and ninety-eight cases of evaluation of body impairment class of pelvic fracture caused by traffic accident accepted by Zhongcheng Institute of Forensic Science in 2016 were collected. The cases were statistically analyzed in terms of the distribution of the number of pelvic ring fracture, the location of pelvic ring fracture and Tile type of pelvic fracture in various healing statuses. Results There were 16 cases without pelvic ring fracture, 18 cases of single pelvic ring fracture, 91 cases of 2 pelvic ring fractures, 73 cases of 3 or more pelvic ring fractures, 136 cases of anterior or posterior pelvic ring fractures, 46 cases of simultaneous anterior and posterior ring fractures. There were 34 cases of Tile A type, 130 cases of Tile B type and 24 cases of Tile C type. Statistical analysis results showed that, the differences in distribution of the number of pelvic ring fracture, the location of pelvic ring fracture and Tile type of pelvic ring fracture in various healing statuses had statistical significance （P<0.05）. Conclusion In determination of the healing status of pelvic fracture, preliminary judgment can be made by using the number of pelvic ring fracture, status of pelvic ring fracture and Tile type of pelvic fracture. Caution is required when dealing with single pelvic fractures （including dislocations）, and determining the destruction of bony pelvis.

Selective pressures in the human bony pelvis: Decoupling sexual dimorphism in the anterior and posterior spaces.

OBJECTIVES: Sexual dimorphism in the human bony pelvis is commonly assumed to be related to the intensity of obstetrical selective pressures. With intense obstetrical selective pressures, there should be greater shape dimorphism; with minimal obstetrical selective pressures, there should be reduced shape dimorphism. This pattern is seen in the nondimorphic anterior spaces and highly dimorphic posterior spaces. Decoupling sexual dimorphism in these spaces may in turn be related to the differential influence of other selective pressures, such as biomechanical ones. MATERIALS AND METHODS: The relationship between sexual dimorphism and selective pressures in the human pelvis was examined using five skeletal samples (total female n = 101; male n = 103). Pelvic shape was quantified by collecting landmark coordinate data on articulated pelves. Euclidean distance matrix analysis was used to extract the distances that defined the anterior and posterior pelvic spaces. Sex and body mass were used as proxies for obstetrical and biomechanical selective pressures, respectively. RESULTS: MANCOVA analyses demonstrate significant effects of sex and body mass on distances in both the anterior and the posterior spaces. A comparison of the relative contribution of shape variance attributed to each of these factors suggests that the posterior space is more influenced by sex, and obstetrics by proxy, whereas the anterior space is more influenced by body mass, and biomechanics by proxy. CONCLUSIONS: Although the overall shape of the pelvis has been influenced by obstetrical and biomechanical selective pressures, there is a differential response within the pelvis to these factors. These results provide new insight into the ongoing debate on the obstetrical dilemma hypothesis.

Pelvic osteotomy in cloacal exstrophy: A changing perspective.

BACKGROUND: The type of osteotomy and pelvic fixation in the management of primary cloacal exstrophy (CE) closure is variable. The purpose of this study was to evaluate primary CE closure outcomes with osteotomy, immobilization, and multi-staging procedure trends over time. METHODS: An institutional database was retrospectively reviewed for patients who underwent primary CE closure from 1960 to 2020. Demographics, osteotomy, fixation, and outcomes were noted. Subanalyses by location of primary closure (AH=author's hospital; OH=outside hospital). RESULTS: Out of 122 patients, multi-stage became more common than single-stage procedures (p = 0.019), with multi-stage associated with higher success rates (77.4% v 45.7%; p = 0.001). The use of any osteotomy increased over time (p = 0.007), with a posterior approach falling out of favor and increasing prevalence of a combined osteotomy (p<0.001). The use of any osteotomy compared to no osteotomy was associated with successful closure (77.6% v 41.7%; p = 0.007). The combined, posterior, and anterior approaches were associated with 90%, 76.2%, and 60.9% successful primary closure rates, respectively (p<0.001). Fixation modalities changed over time as Buck's traction (p<0.001) and external fixation (p<0.001) became more prevalent. Spica casting has become less common (p = 0.0002). Immobilization type was associated with success rates with Buck's (92.1%; p<0.001) and external fixation (86.0%; p<0.001) performing best. CONCLUSIONS: The use of osteotomy and fixation in the CE spectrum has changed markedly. In this cohort, a staged approach with combination osteotomy was associated with better outcomes when using a multidisciplinary team approach. LEVEL OF EVIDENCE: This is a retrospective comparative study (Type of Study: Treatment; Evidence Level: III).

Cement Plug Fragmentation Following Percutaneous Cementoplasty of the Bony Pelvis: Is it a Frequent Finding in Clinical Practice?

PURPOSE: To report the rate of fragmentation of the cement plug following percutaneous cementoplasty with polymethylmethacrylate (PMMA) in the bony pelvis (i.e., pelvic bones or sacrum). MATERIALS AND METHODS: Post-interventional and follow-up CT scans of 56 patients (36 men; mean age of 68.4 ± 15.4) with a total of 98 percutaneous cementoplasty procedures were analyzed. Indications for treatment included painful malignant tumors (42.9%; 42/98) and insufficiency fractures (57,1%; 56/98). Fragmentation of PMMA was recorded for each cement plug. RESULTS: Mean interval between the procedure and the last available CT scan was 29.3 ± 18.8 months. There was no significant difference between the length of follow-up of malignant lesions (27.6 ± 15.1 months) and insufficiency fractures (29 ± 20.5 months) (p = 0.69). Fragmentation was diagnosed following 2/98 (2%) procedures, both in the malignant lesions group. The time intervals between the procedure and the first visualization of cement fragmentation were 6 for the first and 24 months for the second patient. CONCLUSION: Fragmentation of the PMMA plug following percutaneous cementoplasty in the bony pelvis is a rare finding at midterm follow-up. It was only observed in cementoplasty performed in malignant lesions and seems to be more a consequence of local mechanical stresses than as a result of porosity.

Shortened pubic bones in bladder exstrophy: a congenital or acquired phenomenon?

OBJECTIVE: It is accepted that the length of the anterior segment of the pelvis in classic bladder exstrophy is shorter than that of controls. However, studies performed involve children with a wide range of ages. By studying children with classic bladder exstrophy under the age of 1 year, the authors aim to ascertain if there is a congenital pubic bone length discrepancy associated with bladder exstrophy. MATERIAL AND METHODS: Fourteen classic bladder exstrophy patients under 1 year of age and 14 age-matched controls were identified. Three-dimensional (3D) computerized tomography was used to measure the length of the superior pubic ramus bilaterally. In the exstrophy group, scans were performed before bladder closure. The Mann-Whitney U test was used and p < 0.05 was considered significant. RESULTS: There was no significant difference (p = 0.76) in the median age in cases (72 days) and controls (64 days). The median superior pubic ramus length was 19.1 mm in the exstrophy group and 20 mm in the control group (p = 0.99). CONCLUSIONS: Superior pubic ramus length in children under 1 year of age with classic bladder exstrophy is not statistically different from that in control subjects. Therefore, the authors hypothesize that the previously described shortening of the pubic bones is an acquired phenomenon, which may develop after the first year of life.