The fractures in coal are the main migration and output channels of coalbed methane, directly influencing the permeability of the coal seams. It is of great significance to study the effect of fracture distribution in coals on the permeability of coal seam. The development rules of endogenetic and exogenetic fractures are different among various coal lithotypes. There is also difference in the fracture density for the same lithotype with different thicknesses. Through the observation and description of the macroscopic fractures in coal and the origin of fractures in coal, the effect of the coal lithotype and its thickness on fracture development in coal was discussed. It was found through the study that the density of fractures in vitrain band was the maximum for the same coal rank and thickness, followed by clarain band. There were few fractures developed in the durain band. However, the changes of fracture density in three types of bands presented different declining trends for low, medium and high coal rank. There were no fractures developed in the fusain. There were three variation patterns for the fracture densities at the same coal rank and coal lithotype: linear decrease, nonlinear decrease, and first decrease then remaining unchanged. However, the overall trend was that the fracture density decreased with the increase of thickness of coal band for the same coal rank and coal lithotype.
Kim, Jin-Woo;Bae, Tae-Hui;Kim, Woo-Seob;Kim, Han-Koo
Archives of Plastic Surgery
/
v.39
no.1
/
pp.31-35
/
2012
Background : Orbital roof fractures are frequently associated with a high energy impact to the craniofacial region, and displaced orbital roof fractures can cause ophthalmic and neurologic complications and occasionally require open surgical intervention. The purpose of this article was to investigate the clinical features and treatment outcomes of orbital root fractures combined with neurologic injuries after early reconstruction. Methods : Between January 2006 and December 2008, 45 patients with orbital roof fractures were admitted; among them, 37 patients were treated conservatively and 8 patients underwent early surgical intervention for orbital roof fractures. The type of injuries that caused the fractures, patient characteristics, associated fractures, ocular and neurological injuries, patient management, and treatment outcomes were investigated. Results : The patients underwent frontal craniotomy and free bone fragment removal, their orbital roofs were reconstructed with titanium micromesh, and associated fractures were repaired. The mean follow up period was 11 months. There were no postoperative neurologic sequelae. Postoperative computed tomography scans showed anatomically reconstructed orbital roofs. Two of the five patients with traumatic optic neuropathy achieved full visual acuity recovery, one patient showed decreased visual acuity, and the other two patients completely lost their vision due to traumatic optic neuropathy. Preoperative ophthalmic symptoms, such as proptosis, diplopia, upper eyelid ptosis, and enophthalmos were corrected. Conclusions : Early recognition and treatment of orbital roof fractures can reduce intracranial and ocular complications. A coronal flap with frontal craniotomy and orbital roof reconstruction using titanium mesh provides a versatile method and provides good functional and cosmetic results.
Journal of Korean Academy of Oral and Maxillofacial Radiology
/
v.25
no.2
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pp.471-482
/
1995
Bony remodeling pattern of condyle fractures in children are different from in adult for growing of condyle, also might affect treatment and prognosis of the condyle fracture. Subjects of this clinical and radiologic study were 26 temporomandibular joints diagnosed as condyle fracture in 23 patients under 15 years old age. They were treated with conservative method at Dental Hospital of Yonsei University from Jan., 1986 to Oct., 1994. Bony remodeling related with fracture pattern was evaluated. The results obtained are as follows: 1. The ratio of male to female in patients with condyle fracture was 1 : 0.9 and the difference of sex ratio was not noted. Comparing with preschool-age group and school-age group, age frequency was higher in preschool-age group(83%). 2. Fallen down(54%) was the most frequent cause of condyle fractures. Traffic accident and slip down were followed. 3. The most common clinical sign of condyle fractures was tenderness to paipation09 cases). Mouth opening limitation07 cases), swelling(7 cases), malocclusion(3 cases) were next in order. 4. According to sites of condyle fractures, unilateral fractures were in 20 patients and bilateral fractures in 3 patients, therefore total 23 patients-26 cases of condyle fracture were observed. According to fracture distribution, condyle fractures were in 10 patients(44%). Condyle fractures with symphysis fracture(9 patients, 39%), condyle fractures with ascending ramus fracture(2 patients, 9%), condyle fracture with mandibular body fracture(1 patient, 4%), and condyle fractures with mandibular angle fracture(1 patient, 4%) were followed. 5. In displacement pattern of fractured fragment of mandibular condyle, dispiacement(17 cases, 66%) was most common. Dislocation(5 cases, 19%) and deviation (4 cases, 15%) were next in order. 6. During the observation period of fractured condyles, remodeling patterns of fracture sites related with articular fossa were observed with usual condylar shape in 23 cases and with prominently different shape in 3 cases.
Journal of the Korean Association of Oral and Maxillofacial Surgeons
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v.41
no.1
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pp.3-10
/
2015
Objectives: We retrospectively evaluated the impact of mandibular third molars on the occurrence of angle and condyle fractures. Materials and Methods: This was a retrospective investigation using patient records and radiographs. The sample set consisted of 440 patients with mandibular fractures. Eruption space, depth and angulation of the third molar were measured. Results: Of the 144 angle fracture patients, 130 patients had third molars and 14 patients did not. The ratio of angle fractures when a third molar was present (1.26 : 1) was greater than when no third molar was present (0.19 : 1; odds ratio, 6.58; P<0.001). Of the 141 condyle fractures patients, the third molar was present in 84 patients and absent in 57 patients. The ratio of condyle fractures when a third molar was present (0.56 : 1) was lower than when no third molar was present (1.90 : 1; odds ratio, 0.30; P<0.001). Conclusion: The increased ratio of angle fractures with third molars and the ratio of condyle fractures without a third molar were statistically significant. The occurrence of angle and condyle fractures was more affected by the continuity of the cortical bone at the angle than by the depth of a third molar. These results demonstrate that a third molar can be a determining factor in angle and condyle fractures.
Park, Jongohk;Choi, Hyungon;Shin, Donghyeok;Kim, Jeenam;Lee, Myungchul;Kim, Soonheum;Jo, Dongin;Kim, Cheolkeun
Archives of Craniofacial Surgery
/
v.19
no.3
/
pp.190-193
/
2018
Background: This study was conducted to determine the effect of the distributional relationship between dental roots and the mandibular bone on single mandibular bone fractures, which are common craniofacial fractures. Methods: This was a retrospective, single-center study in Seoul, Korea. Patients with single mandibular fractures in the symphysis, parasymphysis, body, and angle area, with tooth structure involvement were included. The control group included patients with simple, bone-level lacerations without fractures. In total, 94 patients (72 males and 22 females) were included in the treatment group, and 125 (71 males and 54 females) were included in the control group. The height of the mandibular bone and the dental root were measured with panoramic radiography. The central incisor represented the symphysis area, the canine represented the parasymphysis area, the first molar represented the body area, and the second molar represented the angle area. Results: In the treatment group, symphysis fractures occurred in 16 patients (17%), parasymphysis fractures in 36 patients (38%), body fractures in 17 patients (18%), and angle fractures in 25 patients (27%). The ratios of the dental roots to the total height of the mandibular bone in the treatment group were 30.35%, 39.75%, 39.53%, and 36.27% for symphysis, parasymphysis, body, and angle areas, respectively, whereas in the control group, they were 27.73%, 39.70%, 36.76%, and 35.48%. The ratios of the treatment group were significantly higher than those of the control group. Conclusion: The results show that the higher ratio of the dental root to the height of the mandibular bone increases the fracture risk.
Objective : The treatment of multiple thoracolumbar spine fractures according to fracture continuity has rarely been reported. Herein we evaluate the clinical features and outcomes of multiple thoracolumbar fractures depending on continuous or noncontinuous status. Methods : From January 2010 to January 2016, 48 patients with acute thoracic and lumbar multiple fractures who underwent posterior fusion surgery were evaluated. Patients were divided into two groups (group A : continuous; group B : noncontinuous). We investigated the causes of the injuries, the locations of the injuries, the range of fusion levels, and the functional outcomes based on the patients' general characteristics. Results : A total of 48 patients were enrolled (group A : 25 patients; group B : 23 patients). Both groups had similar pre-surgical clinical and radiologic features. The fusion level included three segments (group A : 4; group B : 5) or four segments (group A : 19; group B : 5). Group B required more instrumented segments than did group A. Group A scored 23.5 and group B scored 33.4 on the Korean Oswestry Disability Index (KODI) at the time of last follow-up. In both groups, longer fusion was associated with worse KODI score. Conclusion : In this study, due to the assumption of similar initial clinical and radiologic features in both group, the mechanism of multiple fractures is presumed to be the same between continuous and noncontinuous fractures. The noncontinuous fracture group had worse KODI scores in long-term follow-up, thought to be due to long fusion level. Therefore, we recommend minimizing the number of segments that are fused in multiple thoracolumbar and lumbar fractures when decompression is not necessary.
Background: Diaphragmatic injuries following blunt or penetrating thoraco-abdominal trauma are rare, but can be life-threatening. Rib fractures are the most common associated injury in patients with a traumatic diaphragmatic injury (TDI). We hypothesized that the pattern of rib fracture injuries could dictate the likelihood of acute TDIs. Methods: A retrospective study was carried out between April 2014 and October 2018 to analyze patients with TDIs and rib fractures at a major trauma center in London, United Kingdom. Results: Over the study period, 1,560 patients had rib fractures, of whom 14 had associated diaphragmatic injuries. Left-sided diaphragmatic injuries were found in 8 patients (57%). A significant proportion of the rib fractures were located posterolaterally (44.9%). The highest frequency of fractures was found in ribs 5-10, which accounted for 74% of all the fractures. Ten patients underwent surgery, of whom 7 were diagnosed with a diaphragmatic injury intraoperatively after video-assisted thoracoscopic surgery assessment of the pleural cavity. Two patients died due to severe injuries of other organs and the remaining 2 patients were managed conservatively. Conclusion: Our series of patients demonstrates a relationship between significant rib fractures and diaphragmatic injuries in trauma patients, and the diagnostic difficulties in identifying the condition. We found that the location of the rib fractures and the pattern of injury in patients with TDIs were much lower and posterolateral in the chest wall without a preference for laterality. We suggest using a thoracoscope in patients undergoing chest wall surgery post-trauma to aid in diagnosing this condition.
Background: Although the zygomatic arch is an important structure determining facial prominence and width, no consensus exists regarding the classification of isolated zygomatic arch fractures, and the literature on this topic is scarce. To date, five papers have subdivided zygomatic arch fractures; however, only one of those proposed classifications includes the injury vector, although the injury vector is one of the most important factors to consider in fracture cases. Furthermore, the only classification that does include the injury vector is too complicated to be suitable for daily practice. In addition, the existing classifications are clinically limited because they do not consider greenstick fractures, nondisplaced fractures, or coronoid impingement. In the present study, we present a rearrangement of the previously published classifications and propose a modified classification of isolated zygomatic arch fractures that maximizes the advantages and overcomes the disadvantages of previous classification systems. Methods: The classification criteria for isolated zygomatic arch fractures described in five previous studies were analyzed, rearranged, and supplemented to generate a modified classification. The medical records, radiographs, and facial bone computed tomography findings of 134 patients with isolated zygomatic arch fractures who visited our hospital between January 2010 and December 2019 were also retrospectively analyzed. Results: We analyzed major classification criteria (displacement, the force vector of the injury, V-shaped fracture, and coronoid impingement) for isolated zygomatic arch fracture from the five previous studies and developed a modified classification by subdividing zygomatic arch fractures. We applied the modified classification to cases of isolated zygomatic arch fracture at our hospital. The surgery rate and injury severity differed significantly from fracture types I to VI. Conclusion: Using our modified classification, we could determine that both the injury force and the injury vector meaningfully influenced the surgery rate and the severity of the injuries.
The objective of the present study was to assess the prevalence, occurrence pattern, and clinical outcomes of transfixation pinning and casting (TPC) for fractures in Korean native calves, and to identify the advantages of the procedure. The study investigated 52 cases of bone fractures documented from January 2017 to December 2020. Hindlimb fractures (72%) were the most common in bone fractures (n = 50). The distribution of fractures was highest in the tibia (n = 15), followed by the metatarsal (n = 12), femur (n = 9), radius/ulna (n = 8), metacarpal (n = 3), humerus (n = 3), mandible (n = 1), and caudal vertebrae (n = 1). All cases were diagnosed via radiographic evaluation. Closed fractures (86%) were the most common, followed by open fractures (14%). Surgery was performed on 34 calves using intramedullary pin (IM pin), TPC, cross pin, flexible wire (F-wire), and/or plate fixation. The rest of the calves were treated with external coaptation (n = 12) or were not treated (n = 6). Subsequently, 24 calves with follow-up records were evaluated in the bone fracture cases (n = 50). Bone union was observed in 15 (62%) calves; 3 (12%) calves showed non-union; 4 (16%) calves were dead after surgery; and 2 (8%) calves were euthanized at the owner's request. Among the 24 follow-up surgery cases, the most successful cases were tibia fractures (75%) surgically treated using TPC and/or IM pin. These findings suggest that TPC surgery is effective in the management of fractures in Korean native calves.
The fractures of the cervical spine are relatively uncommon, but they may cause serious neurologic deficits temporarily or permanently. So, it is very important to treat the patients early by way of exact evaluation for the sites and the mechanisms of the injuries. The authors reviewed retrospectively 188 cervical spinal fractures in 100 patients from Sep. 1984 to Aug. 1990. Commonly involved levels were $C_5$ and $C_6$ in lower cervical level and $C_2$ in upper cervical level and the sites in each spine were body, lamina and odontoid process. The hyperflexion injury was the most common type of the cervical spinal fractures occupying 53% of all cervical fractures and cause more multiple fractures(2.26 fractures/patient) than in hyperextension(1.68 fractures/patient). In hyperflexion injuries, body, transverse and spinous process were commonly involved but lamina fracture was relatively common in hyperextension injury. The dislocations associated with fractures were developed most commonly in hyperflexion injury and 70% of these were anterior dislocation and the most commonly involved levels were $C_{5-6}$ and $C_{6-7}$. In conclusion, hyperflexion injury needs more close examination for the entire spinal levels than injuries of other mechanisms because it results in more severe fractures with or without dislocation and relatively frequent multiple fractures in different levels.
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