Fractures of the femur and injuries about the knee

Chapter 12 Fractures of the femur and injuries about the knee







4. Treatment of fractures of the femoral shaft: In the adult, internal fixation by intramedullary nailing is the commonest method of treatment. The prime advantage this has to offer is that it generally permits early mobilisation of the patient, thereby lessening the risks of pulmonary, circulatory, renal, joint and other complications, while promoting muscle activity, joint movements and functional recovery. It may also alleviate problems of bed occupancy (which is the historic reason for its introduction). Note, however, that nailing may have to be delayed in favour of damage control orthopaedics. (See p. 44.)


Intramedullary nailing is generally performed using an image intensifier to achieve a manipulative reduction; the fracture is not usually exposed unless this fails. There are many patterns of I-M nail, and much ongoing development. In most cases the maximum possible diameter of nail is chosen after any tight spots have been removed by reaming of the medullary canal. Nails are available for insertion from above (orthograde) through the tip of the trochanter or the piriform fossa, or from below (retrograde) via the knee joint. To prevent rotational instability, most nails allow the use of cross screws inserted above and below the level of the fracture, reducing the need for extensive reaming of the canal and reliance on a tight grip of the nail throughout its length to control this. The original plain intramedullary nail (Küntscher, clover-leaf and other patterns) is now seldom used.


















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20 Other methods of fixation: Plating: This is useful for rapid, rigid fixation in an ischaemic limb requiring vascular repair. Plating has a slightly increased risk of infection and non-union. Compression plating (but see p. 77 for alternatives) is best carried out engaging 8 cortices above and 8 below the fracture, and if possible an interfragmentary screw should be inserted. Compression plating with bone grafting is sometimes used in the treatment of non-union after intramedullary nailing.


21. Aftercare following I-M nailing: Postoperatively, and preferably when the patient is still on the table, the knee should be checked for instability. On return to the ward the limb should be supported on a Braun frame, gutter splint, or Thomas splint. Postoperative radiographs should include good quality views of the proximal and distal femur to exclude any condylar or missed subcapital fractures.


After the first few days care is dependent on the quality of fixation. If a tight-fitting, large-diameter nail is used, and if rotation is well controlled by interdigitating fragments or cross-screws, no external splintage is necessary. The knee may be mobilised and the patient allowed up on crutches. To avoid the risks of the nail bending or undergoing fatigue fracture many prefer to defer weight bearing for 8–10 weeks or until some callus appears. (Shorter periods may be considered when stronger titanium nails are used.) Where the fixation is less sound, a period of a few weeks with the leg cradled in a Thomas splint may be thought desirable.


After union of the fracture, but not before 12–18 months, some advocate removal of the nail in all but the very frail to reduce the risk of a comparatively minor injury causing a fracture of the femoral neck (from local stress concentrations at the end of the nail). This, however, is no longer routine.



































54. Thomas splint (x): Aftercare (v): In those cases where skeletal traction is employed, look for:





During the period a patient spends in bed he should practise quadriceps and general maintenance exercises. Splintage in children should be continued till union (6–12 weeks). In adults, mobilisation of the knee joint and/or the patient may be possible before union is complete.







59. Cast bracing (iv): The cast brace affords moderate support of the fracture, and mobilisation of the patient may be commenced – at first using crutches and with the hinges locked. After 1–2 weeks or as progress determines, flexion can be permitted and the crutches gradually discarded. The brace is worn until union is complete.


A number of commercially produced cast-bracing kits are available using materials other than plaster of Paris (e.g. the bucket may be formed from pre-cut plastic sheet which can be temporarily softened by heating and moulded to shape: resin plaster bandages and polyethylene hinges can be employed). In many cases these render the technique comparatively simple, with the result that the so-called weight-relieving calliper, tubed into the patient’s shoe, is now much less frequently employed for early mobilisation than it was in the past.







64. Special situations: (a) Fracture in the confused patient: Where there is a head injury or a senile confusional state, a patient being treated conservatively may try to remove his own splint; it is possible to prevent this by encircling it with plaster bandages laid on top of the normal crepe bandages (Tobruk splint). This procedure may also be used to give extra security when a patient is in transit.


(b) Metastatic fracture: If death is not imminent, intramedullary nailing is advised to relieve pain. Acrylic cement packed round any defect may give sufficient support to allow the patient to bear weight.


(c) Femoral shaft fracture with (acute) ischaemia of the foot: Nearly all will respond to reduction of the fracture which should be carried out under circumstances which will permit exploration should reduction fail. If the femoral artery is in fact divided, compression plating through the exploratory incision will usually give the rigid fixation that is required prior to the vessel reconstruction.


(d) Femoral shaft fracture with nerve palsy: The majority are lesions in continuity, the common peroneal element being most often affected. If there is reason to believe that there may be nerve division, exploration and internal fixation may have to be undertaken.


(e) Fracture of the femoral neck and shaft: This combination of injuries must be excluded in every case; note too that the ring of a Thomas splint may obscure the affected area. If the shaft fracture is proximal, both fractures may be treated by dynamic hip screw and long plate, but many prefer a Long Gamma 3 nail which is itself the choice in more distal fractures.


(f) Femoral neck fracture with dislocation of the hip: See p. 295.


(g) Fractures of the femoral shaft and patella: Note the following important points: 1. Early mobilisation of the knee is essential for retention of function. 2. Avoid patellar excision when mobilisation of the knee is going to be delayed. 3. Avoid if possible exposure of the femoral fracture and the creation of tethering adhesions between the femur and quadriceps.


The ideal management of this difficult combination of injuries is I-M nailing of the femoral fracture and immediate treatment of the patella appropriate to the type of fracture sustained. If the femoral fracture must be treated conservatively, it is best to leave even badly displaced or comminuted patellar fractures to unite by fibrous union; mobilise the knee as early as possible; excision of the patella can then be carried out as a late secondary procedure when no further flexion can be gained.


(h) Open fractures: Inspection of the fracture site to exclude intramedullary contamination should be part of the initial debridement. If internal fixation is indicated (especially where there are multiple injuries) the infection rate in Grade I and Grade II injuries is said to be no greater after a meticulous debridement and closed nailing than in closed fractures. Grade IIIA fractures with good skin cover and no medullary contamination can be nailed in reasonable safety if reaming is avoided. Grade III B & C open fractures must be carefully assessed, taking into account the greater risks of infection. In some cases nailing may still be advised, while in others the use of an external fixator may be considered safer. With the latter there is always the risk of pin track infections, and the possibility of infection being spread through the medullary canal if secondary nailing is undertaken. The chances of this occurring seem reduced if replacement nailing can be performed within the first week.



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Mar 20, 2017 | Posted by in ORTHOPEDIC | Comments Off on Fractures of the femur and injuries about the knee

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