Analysis of Sacrococcygeal Morphology in Koreans Using Computed Tomography

Rotational V-Y Fasciocutaneous Advancement Island Flap to Cover Deep Sacrococcygeal Defects due to Pilonidal Disease, Pressure Ulcers, and Other Inflammatory Conditions

The sacrococcygeal area supports the lower body and endures mechanical forces during movement. However, current treatment methods for deep caudal sacrococcygeal defects have limitations, resulting in insufficient tissue for deep pocket obliteration and considering only the two-dimensional advancement plane in a three-dimensional defect topology. Our study proposes using a rotational V-Y fasciocutaneous advancement island flap to reconstruct deep caudal sacrococcygeal defects. By considering the three-dimensional nature of the defect, we distinguish a coccygeal plane of the V-Y flap from a sacral plane and set different directions and depths of movement for each plane. From March 2016 to July 2022, 12 patients underwent successful treatment with this surgery, and no complications or recurrences were observed in the study group. Our research found that patients in our study exhibited a smaller intercoccygeal angle than the average angle of the general Korean population, as previously reported. This implies a more pronounced curvature between the sacral and coccygeal planes. Therefore, our methods, which consider the three-dimensional structures of sacrococcygeal pathology, are significant. This technique provides a mechanically robust reconstruction after resecting deep sacrococcygeal pathology, with well-padded tissue to prevent dead space and wound disruption.

Does Sacrococcygeal Skeletal Morphology and Morphometry Influence Pressure Injury Formation in Adults?

GENERAL PURPOSE

To present a study that investigated sacrococcygeal skeletal structure as a possible nonmodifiable intrinsic risk factor for pressure injury and identify possible issues caused by its morphology.

TARGET AUDIENCE

This continuing education activity is intended for physicians, physician assistants, nurse practitioners, and nurses with an interest in skin and wound care.

LEARNING OBJECTIVES/OUTCOMES

After participating in this educational activity, the participant will:1. Recognize the background information the authors considered when planning and conducting their study of sacrococcygeal skeletal structure as a possible pressure injury risk factor.2. Identify the characteristics of the two groups of study participants.3. Choose the results of the study clinicians may consider when implementing evidence-based practice.

Sacralization of Coccygeal Vertebra: A Descriptive Observational Study in Bangladesh

Background: In the sacrococcygeal region, anatomical variation is due to the sacralization of the coccygeal vertebra, which is the due union of/fusion of the fifth sacral with the first coccygeal vertebra of five couples of sacral foramina under-detected or asymptomatic beyond radiological assessment. That is why it is challenging to know the cause of coccydynia, caudal block failure, the difficult second stage of labor, and perineal tears. The present study aims to improve knowledge about the anatomical variation of sacralization of the coccygeal vertebra. Additionally, to find the prevalence of sacralization of coccygeal vertebra in Sylhet, Bangladesh.

Methods: This study was performed on 60 parched, totally calcified, typical sacra of mature-age individuals of undetermined sexes, fulfilling the inclusion criteria from the bone bank of the osteology museum of the Department of Anatomy, Sylhet MAG Osmani Medical College, Sylhet, Bangladesh, from July 2017 to June 2018. Sex determination of the collected unknown sacra was conducted using discriminant function analysis. It was found that 50% (30) were male and 50% (30%) were female. The unpaired t-tests and chi-square were utilized to determine the statistical significance.

Results: Out of 60 sacra, eight (13.33%) samples presented with sacralization. This study found that males had significantly higher straight (p=0.05) and curved (p=0.05) lengths of sacrococcygeal vertebrae. The sacrococcygeal curvature index (SCI) showed statistically significant (p=0.05) differences between the sexes.

Conclusion: Sacralization may exert an impact on the caudal block. It could extend the second stage of the labor process with perineal tears. Therefore, knowledge about the anatomical variation of the coccygeal vertebra is essential.

A novel radiological classification for displaced os coccyx: the Benditz-König classification

BACKGROUND

Treatment of coccygodynia is still a challenging entity. Clear surgical selection criteria are still lacking. The aim of the investigation was to establish a novel radiological classification for surgical decision-making in coccygodynia cases.

MATERIAL AND METHODS

Retrospective analysis of standing and sitting X-rays of coccygodynia patients referred to a single centre from 2018 to 2020. The sacro-coccygeal angle (SCA), the intra-coccygeal angle (ICA) and the difference of the intervertebral disc height (∆IDH) were measured. All coccyges were distributed in subtypes and correlated with the patients' treatment.

RESULTS

In total, 138 patients (female/male: 103/35) with a mean age of 45.6 ± 15.4 years were included in the study. In total, 49 patients underwent coccygectomy. Four different subtypes of displaced coccyges were identified: Type I with a non-segmented coccyx, anterior pivot, increased SCA and ICA from standing to sitting, ∆IDH = 1.0 ± 1.5 mm. Type II with a multisegmented coccyx, anterior pivot, increased SCA and ICA standing/sitting, ∆IDH = 1.1 ± 1.6 mm. Type III showed a posterior pivoted coccyx, negative SCA and ICA, ∆IDH = 0.6 ± 1.6 mm. Type IV is characterized by an anterior-posterior dissociation of the tail bone with a positive SCA, and the ICA shifted from a posterior to an anterior orientation. ∆IDH was - 0.6 ± 1.8 mm.

CONCLUSION

The presented radiological classification could help to facilitate the surgical decision-making for patients with displaced os coccyx. In addition, lateral and sitting X-rays were easy to perform and did not need unnecessary ionizing radiation like in CT scans and were more cost-effective than MRI investigations. The subtypes III and especially IV were more likely leading to surgery.

Morphological Features of the Coccyx in the Turkish Population and Interrelationships Among the Parameters: A Computerized Tomography-Based Analysis

Introduction

The coccyx is well-known to be a highly variable structure considering its morphology. To our knowledge, the relationship between the coccygeal types and other morphological features has not been studied yet. In addition to the interrelations among morphological parameters, this study investigated the morphology and morphometry of coccyx more extensively in the adult Turkish population using computerized tomography images.

Methods

Five hundred subjects who underwent pelvic computerized tomography were included in this study. In addition to coccyx type and the counts of coccygeal vertebrae and segments, the presence of coccygeal deviation, sacrococcygeal joint (SCJ) fusion, SCJ subluxation, intercoccygeal joint (ICJ) fusion, and coccygeal spicule were evaluated. The coccygeal length, sacrococcygeal angle, and intercoccygeal angle were measured on the digital workstation. The findings were subjected to statistical analyses.

Results

The coccygeal vertebra count ranged between three to five, with an average of 4.04 ± 0.48. The range of coccygeal segment count was between one and five, with an average of 2.53 ± 1.02. ICJ fusion in any segment, SCJ fusion, and SCJ subluxation were identified in 397 subjects (79.4%), 343 subjects (68.6%), and 17 subjects (3.4%), respectively. The coccyx types from the most common to the least common were as follows: type 2, type 1, type 3, type 4, and type 5. Coccygeal deviation to the left side was observed in 71 subjects (14.2%), while coccygeal deviation to the right side was observed in 61 subjects (12.2%). A coccygeal spicule was identified in 73 subjects (14.6%). The subjects’ mean age demonstrated no significant difference considering the ICJ fusion (p=0.271), SCJ subluxation (p=0.51), coccygeal spicule (p=0.337), features of coccygeal deviation (p=0.83), and coccyx types (p=0.11). The subjects with SCJ fusion (50.7 ± 18.3 years) were significantly older than the subjects without SCJ fusion (46.5 ± 18.5 years) (p=0.016). The differences between the coccyx types considering the rate of SCJ fusion (p=0.002), ICJ fusion (p=0.04), and spicule presence (p<0.001) as well as the coccygeal vertebra count (p<0.001) were significant.

Conclusion

The presence of coccygeal spicule, a risk factor for coccydynia, is reported to be 14.6% in this study group that represents the Turkish population. This study indicates an association between the coccyx types and the frequency of SCJ fusion, ICJ fusion, and spicule presence and consequently suggests the significance of the coccyx type among the morphological features to cause susceptibility to coccydynia. Due to the multiplicity of the pain generators in the coccygeal region that is established by previous reports, the comparisons of different human populations and the knowledge on the interrelations between the morphologic parameters might facilitate the comprehension of the etiology of coccydynia. The clarification of interrelationship existence among the coccygeal morphological parameters requires further investigations.

Three-dimensional evaluation of the coccyx movement between supine and standing positions using conventional and upright computed tomography imaging

Currently, no three-dimensional reference data exist for the normal coccyx in the standing position on computed tomography (CT); however, this information could have utility for evaluating patients with coccydynia and pelvic floor dysfunction. Thus, we aimed to compare coccygeal parameters in the standing versus supine positions using upright and supine CT and evaluate the effects of sex, age, and body mass index (BMI) on coccygeal movement. Thirty-two healthy volunteers underwent both upright (standing position) and conventional (supine position) CT examinations. In the standing position, the coccyx became significantly longer and straighter, with the tip of the coccyx moving backward and downward (all p < 0.001). Additionally, the coccygeal straight length (standing/supine, 37.8 ± 7.1/35.7 ± 7.0 mm) and sacrococcygeal straight length (standing/supine, 131.7 ± 11.2/125.0 ± 10.7 mm) were significantly longer in the standing position. The sacrococcygeal angle (standing/supine, 115.0 ± 10.6/105.0 ± 12.5°) was significantly larger, while the lumbosacral angle (standing/supine, 21.1 ± 5.9/25.0 ± 4.9°) was significantly smaller. The migration length of the tip of the coccyx (mean, 7.9 mm) exhibited a moderate correlation with BMI (r = 0.42, p = 0.0163). Our results may provide important clues regarding the pathogenesis of coccydynia and pelvic floor dysfunction.

Epidemiology and risk factors of coccyx fracture: A study using national claim database in South Korea

INTRODUCTION

Coccyx fracture usually is a low-energy trauma caused by a backward fall onto a slippery floor of ice. The exact epidemiology of the coccyx fracture is not known. Moreover, the effects of seasonality and weather on the fracture incidence have not been reported. The purpose of this study was to evaluate the annual incidence, gender-preponderance, age-distribution, seasonal variation and climatic risk factors of the coccyx fracture.

METHODS

We identified coccyx fractures, which occurred in South Korea from 2010 to 2018, using nationwide data of Korean Health Insurance Review and Assessment Service (HIRA). International Classification of Diseases-10th Revision (ICD-10) code S322 was used for the identification. Annual incidence of the coccyx fracture was calculated, and the fractures were correlated with gender, age, month of diagnosis and climatic factors.

RESULTS

A total of 238,906 patients were diagnosed with coccyx fracture with an average of 26,545 patients at year. Male to female ratio was 1:2.6. The annual incidence of coccyx fracture was 119.75/100,000 persons in 2018; 33.44/100,000 in male and 86.30/100,000 in female. The incidence rate was the highest at puberty (age of 10-14 years) in male, and at menopause (age of 50-54 years) in female. The incidence was frequent in winter followed by summer. The incidence of coccyx fracture was negatively correlated with the temperature (Pearson correlation factor= -0.67, P<0.01) in winter, while it was positively correlated with the temperature in summer (Pearson correlation coefficient = 0.66, p<0.01). In generalized linear model, old age, female gender, recent year, summer and winter, low temperature and high amount of precipitation appeared as risk factors for coccyx fracture.

CONCLUSIONS

The epidemiologic patterns of coccyx fracture were comparable to other osteoporotic fractures. Findings of our study can be used for epidemiological awareness and prevention campaigns of coccyx fracture.

The Efficacy of Extracorporeal Shock Wave Therapy for Chronic Coccydynia

OBJECTIVE

Coccydynia is a disorder that decreases quality of life with significant functional failure. Extra-corporeal shock wave therapy (ESWT) is used to treat several painful musculoskeletal disorders.

SUBJECTS AND METHODS

The medical records of 34 patients (29 females, 5 males) who had been treated with ESWT between 2017 and 2018 for chronic coccydynia were evaluated. Visual analog scale (VAS) scores were noted at the initial consultation, at each session, and during the initial and follow-up (at 6 months) examinations after the treatment. The 36-item short form (SF-36) quality of life scale survey was conducted at the beginning and end of the treatment. MRI was performed before the start of the procedure and 1 month after the end of the treatment.

RESULTS

The mean VAS score was 9.6 (9-10) before the treatment and 3.4 (0-2) after the treatment (p < 0.05). The VAS score decreased to ≤3 in 79.4% of patients. Bone marrow edema regressed in 6% of patients. Significant improvement was observed in all of the SF-36 parameters, except for two.

CONCLUSION

In our patient group, ESWT provided effective pain control. In order to evaluate the efficacy of ESWT more accurately and sensitively, prospective randomized studies with longer follow-up periods, in which ESWT is compared with different energy doses and different treatment methods, are needed.

Morphological evaluation of the coccyx with multidetector computed tomography

PURPOSE

This study aims to evaluate the morphology of the coccyx in adults with multidetector computed tomography and to contribute to the classification of the coccyx using intercoccygeal and sacrococcygeal angle measurements.

METHODS

The pelvic computed tomography images of 224 patients were retrospectively evaluated. The multiplanar reconstruction and 3D volume rendering images of the coccyx were obtained from all patients at sagittal and coronal planes. The morphology of the coccyx, number of bone segments, the presence of scoliosis, and presence of sacrococcygeal and intercoccygeal fusion were evaluated. After the measurement of coccygeal length, width, and thickness, intercoccygeal and sacrococcygeal angles were also calculated in all patients.

RESULTS

The morphological classification showed that 136 patients (60.7%) had type 1, 65 patients (29%) had type 2, and 17 patients (7.6%) had type 3 coccyx. The intercoccygeal angle was zero degree in five patients (type 0) and one patient had retroverted coccyx (type 5). The coccyx had four segments in 155 patients (69.2%), three segments in 52 patients (23.2%), five segments in 15 patients (6.7%), two segments in one patient (0.4%), and one segment in one patient (0.4%).

CONCLUSION

We determined patients with an intercoccygeal angle of zero degree, which is not mentioned in the literature before, and we propose to use the term "type 0" for these patients in the classification of coccyx. The coccygeal measurements and classification will be instructive for the radiologists and have a guiding role for the future studies.

Coccygeal Morphology on Multislice Computed Tomography in a Tertiary Hospital in India

Study Design

A retrospective, cross-sectional study of 213 patients who presented for abdominal computed tomography (CT) scans to assess coccygeal morphology in the Indian population.

Purpose

There have been relatively few studies of coccygeal morphology in the normal population and none in the Indian population. We aimed to estimate coccygeal morphometric parameters in the Indian population.

Overview of Literature

Coccygeal morphology has been studied in European, American, Korean, and Egyptian populations, with few differences in morphology among populations.

Methods

A retrospective analysis of 213 abdominal CT scans (114 males and 99 females; age, 7–88 years; mean age, 47.3 years) was performed to evaluate the number of coccygeal segments, coccyx type, sacrococcygeal and intercoccygeal fusion and subluxation, coccygeal spicules, sacrococcygeal straight length, and sacrococcygeal and intercoccygeal curvature angles. Results were analyzed for differences in morphology with respect to sex and coccyx type.

Results

Types I and II coccyx were the most common. Most subjects had four coccygeal vertebrae; 93 subjects (43.66%) had partial or complete sacrococcygeal fusion. Intercoccygeal fusion was common, occurring in 193 subjects. Eighteen subjects had coccygeal spicules. The mean coccygeal straight length was 33.8 mm in males and 31.5 mm in females; the mean sacrococcygeal curvature angle was 116.6° in males and 111.6° in females; the mean intercoccygeal curvature angle was 140.94° in males and 145.10° in females.

Conclusions

Type I was the most common coccyx type in our study, as in Egyptian and Western populations. The number of coccygeal vertebrae and prevalence of sacrococcygeal and intercoccygeal fusion in the Indian population were similar to those in the Western population. The mean coccygeal straight length and mean sacrococcygeal curvature angle were higher in males, whereas the intercoccygeal curvature angle was higher in females. Information on similarities and differences in coccygeal morphology between different ethnic populations could be useful in imaging and treating patients presenting with coccydynia.