The Primary Study Of The Fracture Lines In The Quadrilateral Surface Of The Acetabulum Based On Three-dimensional Computerized Tomography Reconstruction

BackgroundThe fracture of acetabulum mostly occurs in young patients, and it more caused by high-energy injuries. Compared with other types of fracture, the incidence of the acetabular fractures is much lower, and most orthopedists have few opportunities to treat the acetabular fractures. Therefore, the minority of orthopedists in Third Grade Class Hospital have the chance to treat the acetabular fracture, and it even becomes a subspecialty. Although the procedure of the treatment of the acetabular fracture without complications is relatively simple, many patients with the acetabular fracture maybe combine with other organ injurys, and it makes orthopedic surgeons to communicate with other professional doctors, such as neurosurgery, cardiothoracic surgery, general surgery, urology, etc. If necessary, according to "Damage Control Orthopaedics, DCO", the acetabular fracture surgery should be performed after the other specialized treatment until the condition is relatively stable.In the current medical conditions, transfering to another department or hospital to treat the difficult acetabular fractures has no technical difficulties, but due to the grasp of acetabular fracture surgery indications and the doubt of treatment options, many patients of the acetabular fractures have missed the best times, lead to the treatment is not in a timely and effective manner.Judet and Letournel divided the acetabulum and the surrounding structure into the anterior column and the posterior column. The anterior column above the iliac crest obliquely downward from the forward ends by pubic symphysis pubis, constituted by a portion of the ilium and pubis. The posterior column go through the greater sciatic notch to the ischial tuberosity acetabular center, including the vertical portion and a portion of the ilium and ischium ischial linked. After the inverted " Y" shaped columns, such as a cradle shape with acetabulum. Inverted after column "Y" shape, such as a cradle-like holding the acetabulum, on the inner side of the quadrilateral surface joined to prevent from the inward displacement of the hip joint.Judet and Letournel have divided all the acetabular fractures into two categories: simple subgroup and complex subgroup, and each of the groups were divided in five types. The classified method of the acetabular fracture is helpful in preoperative evaluation and operation design. In these ten types of fractures, although not separately defined the quadrilateral surface fracture, apart from some simple fracture (simple anterior wall, posterior wall, partial anterior column fracture), other fractures can sweep quadrilateral surface.CT three-dimensional reconstruction have satisfactory results in the observation of the fracture line, helping surgeons to memory the fracture morphology, it is particularly important to determine whether need surgery, preoperative planning and intraoperative fracture location, especially for the junior orthopedists. CT three-dimensional reconstruction can construct the complex acetabulum structure, By rotating, removing the femur and keeping the half pelvic, we can observe the complete location of fracture line. Currently, according to the search, there is no domestic study of the fracture line in the quadrilateral surface. According to a new simplified classification method,which based on quadrilateral surface and vertical fracture line, T.Prasartritha devided the acetabular fracture into the wall acetabular fractures (W), transverse (T) and column (C) of three types, but he neither make detailed description and analysis on the quadrilateral surface of fracture line, or illustrate the performance of the new type in the classic Judet-Letournel type. Therefore, this study attempts to describe and analyze the fracture line in the quadrilateral surface and the relationship between the Judet-Letournel fracture type, fracture line and the acetabular fractures involving the anterior, posterior column.Operation is considered as the first choice of treatment for acetabular fractures. The principle of operation treatment of the acetabular fracture is through good recovery of weight-bearing anatomical reduction of the articular surface to obtain the perfect joint function, and the reduction effect determines the operation effect. However, due to the deep anatomical location of the acetabulum and the complex adjacent anatomical relationship, traditional surgery and internal fixation method excessive pursuit of fracture reduction and fixation stability, result in ignoring the Incision length, exposed widespread, the amount of bleeding and postoperative complications, such as iatrogenic sciatic nerve injury, heterotopic ossification, femoral head necrosis, which ultimately still cause great adverse effects on joint function in patients. At present, the research direction of acetabulum fracture internal fixation method is achieving stability by as little as possible fixation, and the purpose is to minimize the operation trauma as much as possible, shorten operation time, especially for the treatment with the complex acetabular fracture caused with massive trauma.The fracture of acetabulum involving the quadrilateral surface, in addition to the anterior column fracture, posterior column fracture, posterior column with posterior wall fracture, the rest are involving the anterior and posterior columns at the same time. In the treatment of these types of fractures, we can apply fixation methods, such as simple screw type, reconstruction plate and screw or cerclage wire. What’s particularly important is to select the appropriate surgical approach and internal fixation method according to the location of fracture line. As we all know, while double-column fixation is stronger than the single column, but anterior column and posterior column are fixed often separately. Although it increases the stability of the fracture fixation, it won’t reduce the trauma of surgery, for example, the double column fracture is treated with the reconstruction plate to fix anterior column and posterior column by the combined posterior and anterior approaches. The improvement of the acetabular fractures treatment level, the anterior column lag screw fixation, post-column technology becomes more reliable, as well as the emergence of various internal fixation instruments and assisted tools, are changing the traditional fixed pattern.Objective:1、To observe the fracture lines in the quadrilateral surface of the acetabular fracture, and analyze the relationship between fracture lines and the Judet-Letournal classification by collecting three-dimensional computerised tomography (3D-CT) reconstruction of the acetabular fracture.2、To analyze and state the relationship between the fracture line of the acetabular fracture in quadrilateral surface and the anterior column, posterior column.3、To discuss the concept of the treatment of the acetabular fractures, and put forward new explanations.Materials and methods:1、The description of the fracture lines in the quadrilateral surface of the acetabular fractureFirstly, we use "quadrilateral" method to define the quadrilateral surface, A, B, C, D respectively represent the intersection of the anterior column and the posterior column, ischial spine, posterior edge of the obturator ring, and the obturator groove. Line followed by four points constitute a square area is approximate the quadrilateral surface.Then, the fracture lines in the quadrilateral surface of the acetabular fracture were described in this "quadrilateral". Because of the people standing position, we will define the arcuate line approximate as oblique, according to the position, can be summarized the following basic single fracture lines：upper transverse, lower transverse, cis-oblique, trans-oblique, anterior vertical and posterior vertical. The fracture line through the ab side and ad side is defined as upper transverse, through the cb side and cd side is defined as lower transverse, through the ab side and cd side is defined as cis-oblique, through the be side and ad side is defined as trans-oblique, through ad side and cd side is defined as anterior vertical, through ab side and be side is defined as posterior vertical.2、The collection of CT three-dimensional reconstruction dataRetrieved from January2001to November2013, plus a row CT scan and three-dimensional reconstruction of the adult cases of the acetabular fractures, the fracture lines in the image data should be clearly observed in the quadrilateral surface, a total of171cases of complete cases (169cases unilateral,2cases were bilateral),86cases of left hip, right hip in87cases, a total of173patients hips;132males,39females; their age ranged17to74(average,41.6) years old.All acetabular fractures according to Judet-Letournel classification:19cases of anterior column fracture,19cases of posterior column fracture,32cases of transverse fracture,19cases of transverse with posterior wall fractures,9cases of posterior column with posterior wall fracture,20cases of anterior column and posterior hemi-transverse fracture,15cases of T type fracture,40cases of both-column fracture.3、Analysis of the relationship between the fracture lines and the Judet-letournel classification of the acetabular fractureThe fracture of the acetabulum Involving the quadrilateral surface concluding anterior column fracture, posterior column fracture, transverse fracture, transverse with posterior wall fracture, posterior column and posterior wall, anterior column with semi-transverse fracture, T type fracture, double columns fracture, these fractures were collected for Judet-letournel fracture classification. In each case the fracture line in quadrilateral surface of the acetabular fracture line is described, using the above method to summarize the relationship into the two forms.Result:1、According to Judet-letournel classification:19cases were of anterior column fracture,19cases of posterior column fracture,32cases of transverse fracture,19cases of transverse with posterior wall fracture,9cases of posterior column with posterior wall fracture,20cases of anterior column with semi-transverse fracture,15cases of T-type fracture,40cases of double-column fracture.2、Collection the acetabular fracture lines in the quadrilateral surface:224fracture lines were collected, there were71lines of upper transverse,0lower transverse,101cis-oblique,10trans-oblique,13anterior vertical and29posterior vertical;173fracture lines involving anterior column, there were67lines of upper transverse,85cis-oblique,9trans-oblique,12anterior vertical.191fracture lines involving anterior column, there were67lines of upper transverse,90cis-oblique,9trans-oblique and25posterior vertical;170fracture lines involving anterior column and posterior column simultaneous, there were63lines of upper transverse,74cis-oblique,8trans-oblique,8anterior vertical and17posterior vertical.3^The fracture involved anterior column, of them, upper transverse fracture lines accounted for38.7%(67/173), cis-oblique accounted for49.1%(85/173), trans-oblique accounted for5.2%(9/173), anterior vertical accounted for7.0%(12/173). The fracture involved posterior column, of them, upper transverse fracture lines accounted for35.1%(67/191), cis-oblique accounted for47.1%(90/191), trans-oblique accounted for4.7%(9/191), posterior vertical accounted for13.1%(25/191). The fracture involved anterior and posterior column, of them, transverse fracture lines accounted for37.1%(63/170), oblique accounted for48.2%(82/170), vertical accounted for14.7%(25/170).The fracture lines involved anterior column and posterior column are given priority to upper transverse and cis-oblique. The fracture lines of cis-oblique involved anterior column often in higher position,and they often locate around the arcuate line.Conclusion:1、Observation of the fracture line in the quadrilateral surface by the3D-CT reconstruction, can help a orthopedic surgeons, especially youngs, to deepen the understanding of the acetabular anatomy and Judet-Letournel typing. This study maybe has the guiding significance about the choice of operation approach, the reduction techniques, and the choice of the method of internal fixation. 2、The new pedicle screw fixation devices and related support tools can be used in a single surgical approach for the combined fixation between anterior column and posterior column, anterior column and posterior column have been effectively fixed to ensure the stability, in addition, it can shorten operative time, reduce the incidence of surgical trauma and postoperative complications. The combined fixation of anterior column and posterior column, which fixed the broken acetabulum into a whole, it is a new understanding of the surgical treatment of the acetabular fracture.