AKHTAR M KHAN Taken from an Article that was once on the Hope Hospital Website but now
sadly gone Introduction Fractures of the lower limb are common especially in the elderly. They are often associated with considerable morbidity and lengthy hospitalisation and an understanding of lower limb trauma is important.
FRACTURES OF THE FEMORAL NECK (INTRA-CAPSULAR) This is one of the commonest fractures of the elderly, with vast number of the patients being women in the ages between 60-80 years. The fracture usually arises due to a fall on the greater trochanter. The classification commonly used to describe the displacement of the femoral head is referred to as the Gardens classification which is composed of the following stages:
grade1: incomplete impacted fracture of the femoral neck. grade 2: complete undisplaced fracture. grade 3: complete fracture with moderate displacement. grade 4: severely displaced fracture. Pauwels classification however refers to the angle the fracture line makes with the horizontal
Grade 1 Grade 2 Grade 3
Clinically the patient complains of pain in the hip and the limb may be shortened and externally rotated. The principles of treatment are accurate reduction, secure fixation and early mobilisation. In order to decide the type of internal fixation it is important to recall to attention the blood supply to the femoral head. This is by means of intramedullary vessels in the femoral neck, ascending cervical branches in the capsular retiniculum and vessels following the ligamentum fovea. The intramedullary supply is always disrupted by the fracture and the retinicular vessels may also be disrupted if there is displacement of the femoral head.
Blood supply of the proximal femur
As a result of the pattern of blood supply the greater the degree of displacement in femoral neck fractures the greater the incidence of avascular necrosis of the femoral head, therefore grade 1 and 2 gardeners fractures are treated by means of A.O screws and grades 3 or 4 with a hemiarthroplasty. The exceptions to this rule are young patients in whom all grades are treated initially with A.O screws. Management.
Which case X-match 2 units.
Subcapital fracture treated with A.O cannulated screws
INTERTROCHANTERIC FRACTURES OF THE FEMUR These fractures by definition are extracapsular. In contrast to intracapsular fractures there is seldom avascular necrosis of the femoral head due to the presence of intact retinicular vessels. The fracture is caused by a fall on to the greater trochanter and the fracture runs between the lesser and greater trochanter and the proximal fragment tends to displace into varus and there may be a degree of comminution of the postero-medial cortex. The fractures are treated by surgical reduction using a dynamic hip screw.
Management. This is similar to subcapital fractures but the consent is for a Dynamic Hip screw. The classification used for these fractures is referred to as the Jensons classification.
This is usually a fracture of young adults and the fracture pattern may vary considerably depending on the cause. A spiral fracture is usually produced by a fall in which the foot has been anchored whilst a twisting force is transmitted to the femur. Transverse and oblique fractures are often due to direct violence. In addition the fractures may be comminuted or segmental. It has to be remembered that up to two units of blood may be lost from a femoral shaft fracture and that shock may be present therefore it is important to ensure that blood is available. Provisional stabilisation of the fracture may be accomplished by the use of a Thomas splint. There is various methods of treatment which include traction, traction followed by bracing, intramedullary nailing or external fixators.
Intramedullary fixation of femoral shaft fracture
These are produced as a result of direct violence or due to a fall in elderly patients. Clinically the knee is swollen and painful and movement should not be tested, however a record of the neurovascular status should be documented. Radiologically the fracture is seen just above the femoral condyles and the fracture pattern may be transverse or comminuted and the distal fragment is often tilted backwards due the action of the gastrocnemius.
Distal femoral fractures
If the fracture is only slightly displaced or reduces easily with the knee in flexion then it may be treated satisfactorily by traction through the proximal tibia. If closed reduction fails open reduction and fixation with a dynamic condylar screw may be needed.
Management.
Postoperativly unprotected weight bearing is not allowed until the fracture has united.
These are caused by varus or valgus force combined with axial loading. They commonly arise due to road traffic accidents or may be due to a fall from height in which the knee is forced in to valgus or varus. Radiologically lateral, oblique and A.P views will demonstrate the fracture. The fracture pattern is composed of six different types:
Type 1: Wedge fracture of lateral tibial plateau. Lag screws alone suffice for fixation Type 2: lateral tibial wedge fracture with a associated depression.
Fixation is with a buttress Type 3: Depression of lateral.tibial plateau but no associated wedge fracture Type 4: Medial tibial plateau fracture Type 5: bicondylar fracture of both plateau. Type 6: The hallmark of this fracture is the separation of the metaphysis and the diaphysis
Various methods of treatment are indicated involving traction, bracing and operative by means of buttress plating with bone grafting if there is significant depression. Management.
Open reduction of tibial plateau fracture
Fractures of the patella may be caused by direct or indirect trauma. The direct injury may be due to a fall on the knee and fracture is usually easily visible in A.P radiographs.
Displaced fracture of patella treated with circalage wire and screws
In the presence of an undisplaced or minimally displaced fracture were the extensor mechanism is intact the treatment is usually a plaster cylinders three to four weeks. In the presence of comminuted fractures the extensor mechanism may still be intact however patello-femoral osteoartheritis is a common complication. Displaced transverse fractures were the extensor mechanism is disrupted management involves K-wire insertion with tension banding.
FRACTURES OF THE TIBIA AND FIBULA These are relatively common fractures due to the subcutaneous nature of the tibia and in addition open fractures of the tibia are more common then in any other long bone. The method of fracture is usually blunt trauma and the risk of complications is directly related to the degree and nature of soft tissue damage. The fracture pattern is also variable depending upon the nature of the injury and subsequently different method of treatment exist. The principles of management are to limit soft tissue damage and preserve skin cover, to prevent or recognise compartment syndrome, to obtain fracture alignment, encourage healing and to preserve the function of the adjacent joints.
Fracture mid shaft of tibia, note the associated fracture of the fibula
Fractures of the shaft of the tibia are usually cased by rotational forces and lead to spiral fractures .If the fibula remains intact then the displacement of the tibial fracture is usually slight and angulation may be may less then 5 degrees. These fractures can often be managed conservatively with an above knee cast. Fractures of the fibula may be due to direct violence or may occur in association with external rotation and abduction injuries of the ankle. It is important to exclude ankle injuries in the presence of fibular fractures. Fractures of both bones usually occur as a result of direct trauma with road traffic being the commonest cause. The fracture pattern varies considerably depending on the forces involved. Treatment may be composed of: 1. Plaster application following reduction. 2. Insertion of os-calcis pin with subsequent immobilisation in plaster. 3. Internal fixation by means of plates or intramedullary devices. 4. External fixation. The indications for operative management of tibial shaft fractures include: 1. Primary Definite:
Relative:
2. Secondary
The ankle is usually injured by indirect forces with the foot either being externally rotated, inverted, everted or less commonly internally rotated on the tibia. The important factor in ankle fractures is the stability of the ankle mortice. If the mortice is stable ,that is to say the no abnormal movement of the talus is possible the injury is usually easily managed. If the ankle mortice is stable the aim of treatment is to protect the ankle until healing has occurred the mortice is disrupted then it must be reconstructed and held until bone and soft tissue healing is complete.
There is various classifications of ankle fractures however a simple one is noted below: First degree: fracture of one malleolus, no talar shift with a stable ankle mortice. Second degree: bimalleolar fracture or a fracture of one malleolus with ligament tear leading to instability of the ankle. Third degree: trimalleolar fracture with instability in the mediolateral and anteroposterior direction. Fourth degree: supra-syndesmotic fracture of the fibula, possible tearing of the inferior tib- fibular ligament and diastasis. Fifth degree: vertical impaction fracture of the distal articular surface of the tibia.
Bimalleolar fracture of the ankle
The aims of treatment are to restore the position of the talus within the ankle mortice, ensure the joint line is parallel to the ground, the articular surface is in normal congruity and stabilise the fracture until healing has occurred.
Open reduction and internal fixation of bimalleolar fracture
An important point to remember is that ankle injuries may present as fracture-dislocations. In these injuries the skin may be tented and neurovascular structures may be compromised by the displaced bone. It is imperative that the dislocation be reduced immediately, time should not be wasted getting radiographs. Reduction should be carried out using opiate analgesia with emetics and Entanox. It is not important that exact anatomical reduction is achieved as long as the skin tension is reduced and the circulation is restored. Following reduction the foot is stabilised in a below knee back slab.
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