FRACTURES OF THE SACRUM AND COCCYX

Abstract

Although fracture sacrum constitutes a small ratio of all fracture, yet it is of significant importance and this is due the presence of the sacral roots which may be injured with such fractures resulting in neurological symptoms , weakness of the lower limb , urinary , rectal and sexual dysfunction . The most common cause of injury is motor car accident, however fall from - eights , motorcycle accidents & cruch injury form considerable percent of the causative injury . A fewer part is caused due to either miscellaneous or unknown cause , resulting in vertical shearing or lateral compression injuries or transverse fracture of the sacrum . On the other hand fracture coccyx occurs due to direct fall on the buttocks in the sitting position . Diagnosis of these type of fractures may be very difficult and may be missed , where as high as 70% of sacral fractures may be missed on plain radiographs , and this is because the radiographic complexity of the sacrum , the overlying soft tissue, gas shadows and associated injuries in patient with pelvic fracture And so C.T . Scan is mandatory when fracture sacrum is expected, also MRI may play a great role in diagnosis . Physical findings in a patient with fracture sacrum are usually dominated by associ_ ted traumatic injuries. However there are several findings that may lead to diagnose of sacral fractures , among these are marked tenderness , abrasions , heamatomas or open wounds over the sacral region which are formed by the causative trauma , also palpable sacral deformity felt by P/ R examination Sensory examination is more important than motor examination and this is because most of the muscle supply by the sacral roots have an additional nerve supply by the lumbar roots . On the other side fracture coccyx present by severe pain during defecation as well as pain on rectal examination . Sacral fracture is always due to direct trauma to the sacrum however nontraumatic sacral fracture may exit e.g . Insufficiency fracture and stress fracture. Classification of traumatic sacral fracture is a great issue for struggles. Schmidek classified it according to the caustive trauma I . e direct and indirect , Bonnin classified it under six headings : 1- Juxtailiac marginal fracture. 2. Fractures that extent through the first or second sacral foramen with associated upward displacement of the lateral mass of the sacrum. 3. Compressed and comminuted fractures of the upper sacrum . 4 . Fissure fracture extending through the first to fourth sacral foramina and separating the lateral mass from the main body of the sacrum . 5. Traction fracture at the insertion of the sacrotuberous ligament. 6 . Transverse fracture through the level of the third sacral foramen. However, the most recent published classification system by Denis et at, appears to have several distinct advantages over other classifications system . In this system the sacrum is divided into three zones: Zone I is the region of the ala , zone II is the region of the neural foramina , zone III is the region of the central spinal canal . The management of• fracture sacrum was at least as difficult as their diagnosis and classification . This is because patients with fracture sacrum are frequently associated with life threatening injuries . So many authors have chosen to manage these fracture conservatively i.e bed rest with owithout traction . However the unstable fracture causes significant pain and prevents safe patient mobilization from the recumbent position , so most authorities agree that internal fixation of sacrum is indicated when it is unstable . It is difficult to determine the best treatment of sacral fracture from a review of literature . Most series are small or describe several techniques for internal fixations . Methods used for the stabilisation of sacral fracture include : Transiliac sacral b;us , posterior reconstruction plates , local osteosynthesis with plate applied to the sacral lamina ; and ilio- sacral screw fixation with either open or closed reduction , Fixation of the sacrum using transiliac rod is method for open reduction and internal fixation where a large Steinmann pin was fixed from the outer aspect of one ilium through the opposite ilium . Internal fixation with iliosacral screw is a popular method for the stabilization of sacroiliac dislocation and sacral fracture . This technique achieves fixation between the ilium and the sacrum by directing screw from the external surface of the posterior iliac wing into the body of the 1 st sacral vertebra to gain interfragmentary compression .