Pathoanatomy of pertrochanteric fractures - a postmortem study

History Subtrochanteric fractures occur in the proximal region of the femur. Anatomically speaking, the subtrochanteric region of the femur is defined as the interval between the lesser trochanter and approximately 5 cm below it, toward the isthmus of the femur [1, 13]. Subtrochanteric fractures are relatively common, accounting for approximately 10% to 30% of all hip fractures [4, 16]. The subtrochanteric region is subject to tensile and compressive stressors that are substantially greater than the patient's body weight [11] as well as rotational and bending forces that directly influence the observed fracture patterns. These fractures commonly have short proximal fragments of comminution, which are pulled into flexion by the forces of the iliopsoas attaching on the lesser trochanter [9, 10]. Additionally, the comminution can be deformed into an abducted and externally rotated position as a result of the pull on the greater trochanter by the abductor muscles. This proximal abduction deformity can be further amplified as the distal fragment is pulled into an adducted position by the adductor's attachment on the femoral shaft [1, 13]. These muscular-deforming forces make avoiding varus, flexion, or external rotation fracture malreduction more difficult and challenge the fixation construct. Given the complexity of the fracture pattern and anatomy within this region, many fracture classifications have been developed to create a treatment algorithm for surgeons. Subtrochanteric fractures were initially thought to be a subset of comminuted intertrochanteric fractures. A study performed by Boyd and Griffin [3] in 1949 analyzed 300 trochanteric fractures, allowing the authors to develop a classification system based on prognosis and the perceived difficulty of fracture reduction. They divided trochanteric fractures into four designations. The first, Type I, designates a fracture with a linear break extending along the intertrochanteric line from the greater to the lesser trochanter. Notably, with these fractures, the fracture is reduced and maintained in the most simple manner of those within this system [3]. A Type II fracture is comminuted with a fracture line in a similar orientation as Type I, but with points of comminution along the adjacent cortical bone. The reduction of these fractures rises in difficulty with the increasing degree of comminution. In the Boyd and Griffin classification, a Type III fracture is subtrochanteric and may have comminution. The authors noted that there may be elements of Type I and II fractures found within Type III fractures (intertrochanteric extension, cortical comminution, etc) and are accordingly the most difficult of the first three to reduce and fix. Finally, a Type IV fracture is comminuted and extends through the entire trochanteric region and usually into the diaphysis. Frequently there are fracture lines in at least two planes, and consequently fixation must be similarly oriented in two orientations [3]. Many years later, the Fielding classification, described by Dr Joseph William Fielding in 1973, was one of the first to describe fracture patterns within the subtrochanteric region. His classification focused predominantly on the anatomic location of the fracture with Type 1 fractures occurring at the lesser trochanter, Type 2 between 2.5 and 5 cm below the lesser trochanter, and Type 3 occurring 5 to 7.5 cm below the lesser trochanter [7, 8]. Although it was at the forefront of describing subtrochanteric fractures, the Fielding classification was limited as a result of its low reproducibility and its inability to describe more complex fracture patterns [1, 7, 8, 10]. In 1978, Dr Frank Seinsheimer III developed the Seinsheimer classification, a dedicated classification of subtrochanteric femur fractures that incorporated the number of fractured fragments as well as involvement of the medial or lateral cortex [1, 19]. At the time he noted that mechanical failure of pertrochanteric femur fracture fixation often exceeded 20%. Even so, few except Magliato and Fielding had presented a classification system of proximal femur fractures that attempted to describe morphology patterns that contributed to this higher incidence of treatment failure [19]. To have been included in his study, part of the fracture plane must lie between two horizontal lines: (1) at the level of the inferior aspect of the lesser trochanter; and (2) another line 5 cm below that. Notably, as a result of these parameters, this classification system included intertrochanteric femur fractures with distal extension as well as diaphyseal fractures with proximal extension provided that a fracture line crossed this zone. Fractures were classified based on postinjury radiographs and were divided into eight categories based on the number of major fragments, the shape of the fragments, and their location. The first, Type I fractures, are nondisplaced or had < 2 mm of displacement. Type II fractures are two-part fractures and are further subdivided into (II-A) transverse fractures; (II-B) spiral fractures with the lesser trochanter attached to the proximal segment; and (II-C) spiral fractures with the lesser trochanter attached to the distal segment. Type III fractures are three-part fractures and are subdivided into two subcategories: (IIIA) a spiral fracture with the lesser trochanter as part of a third fragment as well as an inferior spike of cortex; and (IIIB) a spiral fracture of the proximal one-third of the femur with the third fragment consisting of a butterfly fragment. Type IV fractures are comminuted fractures with four or more fragments. Finally, Type V fractures are any subtrochanteric fractures with extension through the greater trochanter. Through this work, Seinsheimer concludes that Type IIIA fractures have the highest incidence of fixation failure [19]. Although descriptive, the Seinsheimer classification offered little guidance on what treatment approach to use for a given fracture [1, 19]. In 1992, Dr Thomas Russell and Dr John Charles Taylor published their classification system to describe subtrochanteric fractures. The Russell-Taylor classification accounts for involvement of the fracture within the piriformis fossa and its extension into the lesser trochanter [1, 18]. The aim of this classification was to guide surgeons in treating the injury and to assist with implant selection, which differed from other, established subtrochanteric fracture classifications [1, 18]. By underscoring the unique anatomy of the proximal femur, particularly the extension of the fracture plane into the greater trochanter (lateral wall) or the presence of stability in the lesser trochanteric region (medial cortex), this descriptive schema identifies four different fracture morphologic patterns and was developed to provide the surgeon with direction in determining the proper modality of surgical fixation [5]. All in all, there are > 15 described classification schemas for fractures of the subtrochanteric region [1, 15]. Many classification systems were generated based on the anatomic location of fractures, number of fractured fragments, degree of comminution, or simply on the perceived stability of the fracture pattern [1]. Of these, the Russell-Taylor classification was one of the first to incorporate treatment options for surgeons and has proven useful in identifying the presence or absence of disruption of the lesser trochanter (medial calcar) and the greater trochanter (piriformis fossa). Although there is no predominantly accepted classification scheme for this fracture pattern, the system described by Russell and Taylor is used fairly often in the orthopaedic community as a result of its simplicity and emphasis on surgical planning and treatment [2, 11, 20, 23]. Because this classification system remains one of the most recognizable and routinely used for subtrochanteric fractures, the purpose of this article is to investigate and critically analyze the Russell-Taylor classification and its effectiveness and use in orthopaedic surgery today, particularly as a tool to guide the identification of stable or unstable fracture patterns and to predict the need for reoperation in the perioperative period [9, 17, 23]. Purpose The aim of this classification was to guide surgeons in determining the integrity of the proximal fragment and whether plating or intramedullary nailing would be the ideal mode of fixation [18]. First, the classification identified whether the piriformis fossa was disrupted and, second, evaluated the extent of lesser trochanter involvement (Fig. 1) [12]. This information was felt to be critical in deciding whether to use a standard locking intramedullary nail that extended from the greater to the lesser trochanter or to perform reconstruction nailing with a cephalomedullary device [11, 18, 20, 22]. One reason the integrity of the piriformis fossa was highlighted in this system was the previously held belief that fractures disrupting the piriformis fossa may benefit from plating rather than nailing; surgeons were concerned that fixation of the proximal fragment would be lost with use of a piriformis starting point in these situations [1, 11, 18]. As a result of disruption of the piriformis fossa, like in Type 2 fractures, Russell et al. suggested that hip screw implants were a superior option, rather than intramedullary devices, when the fracture pattern involved the piriformis fossa (Types 2-A and 2-B) [9, 10, 13]. However, with more advanced nailing techniques through the greater trochanter, the nail "falling out of the back" of the proximal fragment has become less problematic [11, 18] and ultimately diminished the utility of the Russell-Taylor classification system [1, 11, 18].Fig. 1: This image describes the four types of fractures described by the Russell-Taylor classification system. Type 1-A fractures describe fractures that do not involve the piriformis fossa. Type 1-B fractures do not involve the piriformis fossa but do involve the lesser trochanter. Type 2-A describes fractures through the piriformis fossa but not involving the lesser trochanter. Type 2-B are fractures involving both the lesser trochanter and piriformis fossa [14, 18]. Reprinted with permission from N. G. Lasanianos and N. K Kanakaris et al. [10].Classification Type 1: Fractures not involving the piriformis fossa of the femur. Subdivided into: Type 1-A: Fractures that extend below the lesser trochanter of the femur; and Type 1-B: Fractures that involve the lesser trochanter of the femur. Type 2: Fractures that do involve the piriformis fossa of the femur. Subdivided into: Type 2-A: Fracture patterns with a stable medial buttress; and Type 2-B: Fracture patterns with no medial femoral cortex stability. Validation There are multiple classification systems that have been developed to describe subtrochanteric fractures [1, 15]. Two studies have analyzed the inter- and intraobserver reliability of the Russell-Taylor classification system: Guyver et al. [10] and Imerci et al. [12]. Guyver et al. [10] analyzed various subtrochanteric descriptive classifications, one of which was the Russell-Taylor classification system. In this study, four observers analyzed 32 subtrochanteric fractures and compared the reliability of the classification system. The observers were asked to evaluate the same fracture patterns on two separate occasions to assess intraobserver reliability [7]. Their study concluded that the mean κ value for interobserver reliability and intraobserver reliability was κ = 0.35 (fair) and κ = 0.25 (fair), respectively. However, the study by Imerci et al. [12] had an alternative conclusion. Their study utilized 35 patients with subtrochanteric fractures that were classified 6 weeks apart by 16 observers, eight of whom were specialists and eight of whom were assistants [12]. Imerci et al. [12] concluded that there was substantial agreement regarding interobserver reliability of the specialists with κ = 0.695 and 0.754 on first and second evaluations, respectively. Similarly, there was also substantial agreement for the interobserver score of assistants with κ values of 0.695 and 0.749 on their first and second evaluations, respectively, as well. Furthermore, the intraobserver reliability scores among specialists were determined as nearly perfect at 0.955 (range, 0.75-1.00) and 0.915 (range, 0.82-0.97) and 0.855 (range, 0.75-0.96) and 0.90 (range, 0.79-0.97) for the assistants. Based on the results by Guyver et al. [10], the Russell-Taylor classification's low inter- and intraobserver reliability would indicate that this system has a high risk of miscommunication, misdiagnosis, and erroneous surgical decision-making. In contrast, Imerci et al. [12] advocated that the Russell-Taylor classification was more reliable and reproducible than other classifications for subtrochanteric fractures analyzed in their study. Imerci et al. [12] stated that, as a result of a larger volume of images analyzed and more observers participating in evaluation, their study was more reliable than the Guyver et al. [10] study. Limitations According to Guyver et al. [10], the greatest limitation of the Russell-Taylor classification is that the intra- and interobserver reliability of this system is limited, typically in the range of "fair" or worse [10]. As noted, this means that the classification should be used with great care, if at all. However, Imerci et al.'s [12] results showed almost perfect repeatability and the interobserver reliability was substantial, encouraging the overall use of this classification system among surgeons. The stark contrast between these studies indicates that additional studies should be performed to better evaluate the descriptive capacity of the Russell-Taylor classification system. Regardless of the inter- and intraobserver reliability in identifying and describing these fractures, this classification system continues to have limited value with regard to treatment approach [1, 10]. As stated, the Russell-Taylor classification was created primarily to guide surgeons with surgical treatment. When the system was developed, fracture patterns that did not extend into the piriformis fossa (mainly Russell-Taylor Type 1 fractures) were best treated with intramedullary nailing, typically using a cephalomedullary nail with a piriformis entry point [15]. However, with newer orthopaedic implant designs and expanding surgical indications, most subtrochanteric fractures now are treated with intramedullary nails regardless of their Russell-Taylor classification, further limiting the system's utility [1, 10, 11, 14]. Although the Russell-Taylor classification's reproducibility and reliability are debated among authors, the addition of trochanteric-starting intramedullary nails have diminished this system's overall clinical relevance. Starr et al. [21] performed a randomized study that found no difference in outcome regarding a trochanteric versus piriformis fossa entry portal in fixation of this fracture pattern. They suggested that the quality of the fracture reduction was more important than whether the piriformis fossa was disrupted [21]. Another limitation of this classification system is that the degree of comminution is often not fully appreciated on radiographic imaging, especially in elderly patients with osteoporotic bone [23]. As such, intraoperative findings often reveal additional complexity to the injury, further complicating surgery. Finally, the lack of well-defined parameters encompassing the subtrochanteric anatomic region adds an element of vagueness to the already complex issue at hand. Loizou et al. [15] identified 15 different classification methods for subtrochanteric fractures with only eight classification systems defining which area of the bone was the subtrochanteric region. Although generally accepted as 5 cm distal to the lesser trochanter, Loizou et al. [15] found that there was no anatomic agreement among the different classifications on the distal border of the subtrochanteric region, particularly in those fractures that crossed anatomic boundaries [15]. Conclusion An ideal classification system needs to be reliable, reproducible, and able to accurately communicate between surgeons involved in care [3]. The Russell-Taylor classification, although not perfect with regard to reliability and reproducibility, remains one of the most widely known classifications for subtrochanteric femur fractures [2, 11, 20, 23]. With advancements in reduction techniques, nailing procedures, and improved versatility of implants, there is decreased clinical utility of the Russell-Taylor classification system. Although the classification system aids in describing the fracture's pattern, at this point, this system is of limited clinical relevance. Recognizing the variability in describing these fracture patterns, as concluded by Guyver et al. [10] and Imerci et al. [12], the authors of this study recommend caution while using the Russell-Taylor classification to describe fracture patterns. Furthermore, we recommend against its use to guide treatment of patients with subtrochanteric femur fractures. With such a commonly used classification system, additional studies must be done to resolve and conclude whether the reproducibility and reliability of this classification system are consistent and efficacious to maximize the potential to treat patients safely [2, 11, 20]. Given the complex nature of this fracture pattern and the detrimental effect on quality of life after injury, one can infer that an all-inclusive and fully descriptive classification system would also be equally complex [6]. Nonetheless, because of its historic significance to the study, orthopaedic trauma, and its relative familiarity, the Russell-Taylor classification may serve a role in describing the initial fracture pattern, even as the advent of trochanteric starting intramedullary nails and advanced orthopaedic implants have limited its clinical relevance.

Patterns of Carpal Deformity in Scaphoid Nonunion: A 3-Dimensional and Quantitative Analysis

Introduction:Two methods using cannulated headless screws can be used for scaphoid fractures: Inserting the screw through the distal fragment and then into the proximal fragment through a palmar approach under direct vision or fluoroscopic guidance and inserting the screw in the proximal-to-distal direction through a dorsal approach with fluoroscopic guidance. These methods are sometimes difficult to use in oblique fractures when trying to achieve screw fixation perpendicular to the fracture plane.The most common mechanism of injury in the scaphoid fracture is forceful wrist hyperextension and punching something. Less commonly, a direct blow to the wrist also can cause a fracture. The mechanism of fracture by a direct blow to the wrist is not completely clear.Case Presentation:We experienced two rare cases of scaphoid fracture in goalkeepers sustained when they saved a goal by contacting the soccer ball with the palm of their hand. Both fractures were proximal oblique fractures. We performed through a dorsal approach to insert the screws in the distal-to-proximal direction under direct vision assisted with fluoroscopy. Bone union was noted after surgery in both cases. They returned to their occupations without wrist pain.We investigated the relationship between the fracture line and wrist position using a fresh cadaver. The experiment revealed that the fracture line of the scaphoid matched the dorsal edge of the articular surface of the radius with the wrist in 30° of dorsiflexion and 20° of ulnar deviation.Conclusion:In this report, we reported rare cases of scaphoid fracture due to contact with the soccer ball on the palm. We propose a surgical approach for an oblique fracture of the proximal scaphoid that used guide wires and screws, but was performed through a dorsal, and not palmar, approach to insert the screws in the distal-to-proximal direction.We presume that coronal shear stress to the scaphoid bone occurred when the palm contacted the ball with the wrist positioned at 30° dorsiflexion and 20° ulnar deviation.

Our goal was to analyze the movement of acute scaphoid waist fracture fragments and adjacent bones in a common coordinate system. Our hypothesis was that the distal scaphoid fragment flexes and pronates and the proximal fragment extends. Computed tomography (CT) scans of patients diagnosed with an acute scaphoid waist fracture were evaluated using a 3-dimensional (3D) model. The scans of 57 nondisplaced and 23 displaced fractures were compared with a control group of 27 scans showing no pathological involvement of the wrist. Three anatomical landmarks were labeled on the distal and proximal fragments of the scaphoid, the lunate, and the trapezium. Each set of labels formed a triangle representing the bone or fragment. Four landmarks were labeled on the distal radial articular surface and used to create a common coordinate system. The position of each bone or fragment was calculated in reference to these coordinates. The displaced fracture group showed significant extension, supination, and volar translation of the proximal scaphoid fragment when compared with the other groups. The lunate tended toward a supinated position, which was not statistically significant. The distal scaphoid fragment and the trapezium showed no movement. In acute displaced scaphoid fractures, it is the proximal fragment that displaces and should be reduced. The typical "humpback" deformity is actually a "proximal extension" deformity, the consequence of displacement of the proximal fragment of the scaphoid (with the lunate). Manipulating only the proximal fragment (with the lunate) may be technically easier and more effective than manipulating both fragments.

Subxiphoid video-assisted thoracoscopic surgery (VATS) is considered a safe and feasible operation for anterior mediastinal mass resection. However, diaphragmatic injury, presented as tearing or puncturing, may occur during subxiphoid VATS despite of low incidence. This study aims to explore risk factors for diaphragmatic injury in subxiphoid VATS, as well as strategies to reduce occurrence of the injury. We retrospectively reviewed clinical records of 44 consecutive adult patients who underwent subxiphoid VATS. These patients were divided into two groups: diaphragmatic injury group and non-injury group. Perioperative outcomes and anatomic features derived from 3D CT reconstructions were compared between the two groups. Significant differences were observed in operation time (223.25 ± 92.57 vs. 136.28 ± 53.05, P = 0.006), xiphoid length (6.47 ± 0.85 vs. 4.79 ± 1.04, P = 0.001) and length of the xiphoid below the attachment point on the diaphragm (24.86 ± 12.02 vs. 14.61 ± 9.25, P = 0.029). Odds ratio for the length of the xiphoid below the attachment point on the diaphragm was 1.09 (1.001-1.186), P = 0.048 by binary logistic regression analysis. We identified the length of the xiphoid below the attachment point on the diaphragm as an independent risk factor for diaphragm injury during subxiphoid VATS. Prior to subxiphoid VATS, a 3D chest CT reconstruction is recommended to assess the patients' anatomic variations within the xiphoid process. For patients with longer xiphoid process, a higher incision at the middle and upper part of the xiphoid process, and partial xiphoid process resection or xiphoidectomy is preferred.

Biomechanics: The biomechanical concept of compression nailing consists of the use of an intramedullary device that is inserted into the medullary cavity without jamming and that allows a relative movement of the fragments after locking. First, the implant is firmly attached to the distal main fragment, using conventional locking screws at the nail tip. Next, the other main fragment, which contains the nail entry portal, is fixed via a locking screw in a longitudinal slot in the nail. The compression screw is inserted, and produces distraction between the proximal part of the nail and the locking screw in the slot. This distraction results in relative movement between the intramedullary nail and the proximal fragment, compressing the fixed distal fragment against the proximal. Indications: Whether or not compression nailing can be used depends on the axial stability of the fracture or osteotomy. Therefore, simple fracture patterns, nonunions and elective osteotomies are excellent indications. The same is true for fusions of the knee or the ankle joint, providing that there are no major bone defects. Benefits: The chief benefits of compression nailing are controlled fragment apposition, and superior stability, especially to rotational forces, as compared with conventional intramedullary nailing techniques. The favorable biomechanical conditions provided allow early full weight bearing, and ensure a high rate of bony union. With implants and instruments optimized for compression nailing, this technique should widen the scope and enhance the outcome of intramedullary nailing.

Does 3D CT reconstruction help the surgeon to preoperatively assess calcaneal fractures?

Purpose: The purpose of this study is to analyze the clinical and radiographic results of treatment of unstable pertrochanteric hip fractures in which the fracture line is extended distally or the width of the canal is wide using a long intramedullary nail. Materials and Methods: From January 2005 to January 2010, we conducted an analysis of 20 cases of unstable pertrochanteric hip fractures (over AO/OTA 31 A2.2) treated using a long intramedullary nailing and followed up for more than 12 months. Using postoperative and last follow-up radiographs, we measured TAD, Cleveland index, neck-shaft angle, sliding length of the lag screw, and union time. Clinically, we measured the operation time, the amount of transfusion, and Parker and Palmer’s mobility score. Results: The mean bony union time was 16.4 weeks(10-21 weeks). The mean sliding length of the lag screw was 4.3 mm(1-10 mm) and the mean varus angulation after surgery was 5.1。(3-8。). The mean operative time was 118 min(60-140 min), and the mean transfusion amount was 2.0 pint(0-4 pint). According to Parker and Palmer’s mobility score, mean preoperative score was 7.5 points and mean postoperative score at last follow-up was 6.9 points. Conclusion: In treatment of unstable pertrochanteric hip fractures, when the fracture line was extended to below the lesser trochanteric level or the medullary canal width was wide, use of a long intramedullary nail showed excellent clinical and radiologic results and can be regarded as a good treatment option.

The aim of this study is to determine normal glenopolar angle (GPA) values on bone specimens of the scapula and compare them with various radiological views and CT examination. GPA values were measured on 100 mature, dry, non-paired scapulae, 20 pairs of dry scapulae, 50 AP radiographs of the shoulder, 50 Neer I views, 50 AP chest radiographs and 20 3D CT reconstructions of the scapula. Measurements made on bone specimens of the scapula showed an average GPA value of 42.3°; the mean absolute side-to-side difference was on average 1.6°. The average GPA measured on 50 AP shoulder radiographs was 35.9°, on Neer I views 40.6° and AP chest radiographs 37.1°, with the mean absolute side-to-side difference on average 4.9°; on 3D CT the average GPA was 43.0° and the mean absolute side-to-side difference on average 1.4°. GPA values depend on the method of measurement used. Measurements made on 3D CT reconstructions and Neer I views showed almost the same values as those measured on bone specimens. The values measured on AP shoulder views and AP chest radiographs were statistically significantly lower. Side-to-side variability (right and left) measured on 3D CT reconstructions was insignificant, and the obtained values corresponded to the values from bone specimens. Therefore, the best method to measure the GPA is a 3D CT reconstruction and an exact Neer I projection.

Intramedullary fixation is the mainstay of treatment for femur fractures in the adult trauma population. With subtrochanteric fractures, accurate reduction and stable fixation become technically challenging. Adjuvant blocking screws in the proximal fragment can effectively be used to prevent varus and apex anterior malalignment when intramedullary nails are used in these fractures. Blocking screws decrease the canal volume, thereby allowing the intramedullary device to control the proximal segment. This aids in improving alignment between the proximal and distal fragments during reduction. We review the cases of six patients with proximal femur fractures who were treated with intramedullary nailing in conjunction with the placement of blocking screws.

Objective To accurately quantify three-dimensional in vivo kinematics of fractured scaphoid in wrist flexion-extension and radial-ulrar deviation, and to provide the theoretic bases for clinical application. Methods The bilateral wrists of 10 adult volunteers with scaphoid fractures were imaged by spiral CT at neutral position, at 15°, 30°, 45° and 60° of wrist flexion-extension, at 10° and 20° of radial deviation and at 10°, 20°, 30° and 40° of ulnar deviation. The 3D quantitative measurement and analysis of fractured scaphoid were performed in our computer-operated simulation system. The 3D kinematic data of the proximal and distal fragments of the fractured scaphoid were measured using the center of articular surface of the distal radius as reference. The kinematic data from the healthy side scaphoid were also acquired for comparison. Results After the scaphoid was fractured, being compared with the normal scaphoid, the proximal fragment of the scaphoid did not show obvious changes of rotation and translation. The changes of the distal fragment of the scaphoid were significant. When the wrist was positioned at 10° radial deviation and 30° extension, the distance between the centroids of distal and proximal fragment models was the smallest. Conclusion In the treatment of scaphoid fractures, the wrist should be kept at 10° radial deviation and 30° extension to ensure shortest distance between the fracture fragments and hence satisfactoiy reduction. The study provided some theoretic and technical reference for treatment of scaphoid fractures. Key words: Scaphoid bone; Fractures; bone; Imaging; three-dimensional; Kinematics; In vivo

Purpose Currently, treating femoral neck fractures (FNFs) with the inverted triangle configuration requires alignment between the femoral neck’s long axis and the axis of cannulated compression screws (CCS). To address whether the ‘parallel’ alignment is the most effective approach for fractures with varying Pauwels angles, we employed finite element analysis (FEA) to investigate how different angles between fracture line and CCS affect stability, based on various Pauwels angles. This study aims to offer improved guidance for treating FNFs with the inverted triangle configuration. Methods FNF models with Pauwels angles of 40°, 50°, 60°, and 70° were developed. The CCS were positioned in an inverted triangle configuration based on the angle between the fracture line and CCS. Using FEA, we compared the biomechanical properties of each model to evaluate the stability by evaluating five key parameters: maximal stress in the proximal femoral fracture fragment (MPFS) and implants (MIS), maximal displacement of the bone (MBD) and implants (MID), and maximal relative displacement of the fragments (MRD). Results For Pauwels angles of 40°, 50°, 60°, and 70° across different FNF models, various parameters exhibited similar results. The MPFS showed an upward trend with a decrease in the angle, whereas the MIS, MBD, MID, and MRD all exhibited downward trends. Conclusion The FEA results suggest that decreasing the angle between the fracture line and the CCS for the treatment of FNF can increase the tension resistance of the model, thus increasing the model’s stability.

Spinal cord lesions are not detectable on roentgenograms and computed tomography (CT) scans. Magnetic resonance images (MRIs) are able to make soft-tissue lesions visible. Interpretations of MRIs, CT scans, and roentgenograms were compared in 25 patients and three postmortem specimens with spinal cord injuries. In 14 patients and one specimen with normal roentgenograms and CT scans, the MRI demonstrated ten soft-tissue injuries as minimal displacement of the vertebral bodies or as a high signal intensity in the disc space, indicating a hematoma. Seven of the ten patients demonstrating soft-tissue injuries also had an intramedullary lesion, while in five of the 15 patients with normal CT scans, only a medullary lesion was present on MRI. In 11 patients and two postmortem specimens, fractures were seen on roentgenograms and CT scans. In these patients, the CT was superior to the MRI in detecting small bony fragments, but the medullary lesions were visible only on the MRIs. An intramedullary low signal intensity corresponded to macroscopically visible hemorrhages in the three postmortem specimens. The MRI provided important information in patients with neurologic deficits. No obvious pathologic changes were evident on the roentgenograms and CT scans. The MRI also demonstrated intramedullary and extramedullary soft-tissue lesions and was useful in establishing a diagnosis and in choosing appropriate therapy. CT, on the other hand, was superior in detecting small bony fragments and fracture lines.

Three-dimensional computed tomography mapping and morphological study of distal radius fracture (OTA/AO types 23B and 23C).

The recent progress in understanding the biomedical basis for temporomandibular joint. (TMJ) therapy as well as in computer and imaging technologies is beginning to provide novel insights into TMJ reconstruction, rational diagnostic and therapeutic strategies. Several methods are available for imaging the TMJ. These include basic radiography (such as panorexes and corrected tomograms), ultrasonography, magnetic resonance imaging, and spiral or conebeam computed tomography. The latter technologies allow the joint to be visualized as sections in different planes and can also be rendered as 3 D volumetric reconstructions to enhance diagnostic capabilities. The aim of the study is demonstrate patient's therapy including 1 year recall. This contribution deals with 3D analysis of the mathematical and computer modeling of biomechanics of the jaw. Case report monitors step by step treatment plan, preprosthetic surgery, mandibular reconstruction and process of healing. 3D- CT was used to monitor the patient with dental cysts. The mathematical and computer TMJ models analysis using overlapping of 3D CT before and after 1 year therapy shows the stability of TMJ partial prosthesis reconstruction. Mathematical modeling and mathematical simulation of the reconstruction of patient jaw and/or patient TMJ may predict the joint loading of the reconstructed condyle. Our study demonstrated practical use of 3D images during TMJ therapy. Although many of the disorders involving the temporomandibular joint and associated structures can be diagnosed clinically on the basis of the history and physical findings, there are others that require the use of various imaging techniques to make an accurate diagnosis or to determine the extent of involvement. Imaging the hard and soft tissues of the temporomandibular joint can be used not only for treatment planning but also long-term treatment evaluation.