80. Proximal Tibia
From Primary Surgery
80.1 Infracondylar fractures of the tibia
An infracondylar fracture is the result of a blow to the patient's leg fracturing his tibia and fibula 5 cm below his knee, as in A, Fig. 80-1. Although his lower leg may bend in any direction, there is usually only slight lateral shift and no overlap or rotation. The fracture does not enter his knee. You can treat him in a long leg cast, just as you would if his fracture were more distal in his tibia. If the fragments are displaced, manipulate them into position, and apply a long leg cast (81.4) for 6 weeks. Then remove it and start protected weight bearing in crutches.
80.2 T-shaped fractures of the shaft of the tibia into the knee
An adult falls from a height, drives the shaft of his tibia up between the condyles of his femur, and injures the soft tissues of his knee severely. The condyles of his tibia may split apart, as in B Fig. 80-1, so that the shaft of his tibia rides up between them. Distal tibial traction (80.5) will often reduce these fractures adequately.
80.3 Fractures of a tibial condyle (`bumper fractures')
This fracture is usually the result of a blow to the outer side of the patient's knee from the bumper of a car, which fractures one of the condyles of his tibia, usually the lateral one. There are three varieties of this fracture: (1) His lateral condyle may split vertically and hinge outwards, as in C, Fig. 80-1, while his fibula remains intact. (2) The articular surface of his lateral condyle may be depressed or pulped without harming his fibula, as in D, in this figure. Minor varieties of this fracture may be difficult to see on an X-ray, so look carefully. (3) The lateral condyle of his tibia may be displaced downwards, leaving its articular surface unharmed, while breaking the neck of his fibula (E). Fortunately, you can usually neglect the displacement of most of these fractures. Distal tibial traction (80.5) with early knee movement will usually give a patient full movement in his knee.
80.4 Comminuted fractures of the upper tibia
In a comminuted fracture of the upper tibia the fragments are usually held in a sleeve of intact periosteum, as in F, Fig. 80-1. If so, you may be able to reduce them by strong traction, and then treat him in distal tibial traction (80.5).
80.5 Treating fractures of the proximal tibia-distal tibial traction
The treatment for fractures of the proximal tibia differs considerably from the treatment of those of its shaft. If the patient's knee joint is not involved you can treat him in a long leg cast, in the same way as you would if the fracture were more distal in his tibia. But if the fracture enters his knee joint and disturbs its articular surface, he will need early active movements to mould the articular surfaces of his disturbed knee joint into place. Perkins traction is not safe because a pin through his upper tibia would pass too close to the fracture line, or through it, and might cause osteomyelitis, or infect his knee. The alternative is to put the pin through his lower tibia-the middle of his tibia is unsuitable because it is much too hard. If the articular surface of a patient's knee joint is disturbed, distal tibial traction is much better than a cast, because it reduces most of the displacement, it maintains reduction, and it provides early movement without weight bearing. Early movement helps the surfaces of his knee to slide over one another and minimizes stiffness.
FRACTURES OF THE UPPER TIBIA
If you are going to refer the patient for internal fixation, do so early, within the first week, because the cancellous bone of his tibia soon becomes soft and difficult to fix.
If he has a tense haemarthrosis, aspirate it.
If necessary, apply any of the following manoeuvres under
anaesthesia, before applying distal tibial traction.
If his lateral tibial condyle is displaced, put a strong varus strain on his knee, while you try to mould the displaced
fragments proximally into place.
If his tibial condyles are comminuted, flex and extend his knee a few times to mould the fragments into shape. If they
are much displaced, ask an assistant to pull on the patient's
leg while you try to squeeze them into place between your
hands.
If the fragments are difficult to reduce, insert a distal tibial Steinmann pin. While the patient is still anaesthetized, apply 10 to 15 kg traction for a few minutes through this pin, and manipulate his knee as above. Send him back to the ward in
bed with traction applied.
DISTAL TIBIAL TRACTION See Section 70.11. Use an ordinary
bed with a pulley over the end. Apply 5 kg or one fourteenth
of the patient's body weight. Place a pillow lengthwise under
his lower leg.
CAUTION ! (1) Never put a pad directly under his heel, or pressure sores will form. Instead, support his lower leg to keep his heel off the bed. (2) Don't put a pillow under his knee where it may obstruct the vessels or press on his popliteal nerves.
Next day, encourage him to move his hip, his ankle, and the joints of his tarsus and toes. Exercise his leg gently at first, and then more vigorously.
Put a sling under his lower thigh, with a cord passing over an overhead pulley as in Fig. 80-2, and ending in a handle so that he can raise his thigh, and exercise his knee. He should eventually be able to bend it to 90°. Don't put a sling directly under his knee, because it may injure his common peroneal nerve. A sling is essential because you cannot lower the fracture boards and let him dangle his leg, as you can with Perkins traction.
LATER CARE He should have fully controlled flexion and extension of his knee of at least 90° by 4 weeks. Continue to apply traction for 6 weeks, then get him up and teach him to walk on crutches for another 6 weeks, as in Section 77.1, without weight bearing but following the normal movements of walking. Follow this by partial weight bearing with crutches for 6 more weeks.
At 12 weeks he should be walking without a stick, unless he is old and frail. If traction is continued for too short a time, there is risk of lateral angulation. Most patients can move their injured knees and walk normally at 6 months.
80.6 Fractures of the tibial spine
In this uncommon injury a child falls on his bent knee, drives his femur posteriorly on his tibia, and pulls his anterior cruciate ligament away from its insertion into his tibia. As it comes away, it brings with it a wedge-shaped piece of his tibial plateau, which is usually called the 'tibial spine'. His knee fills with blood, either immediately, or not until the following day; it is tender all over, and he cannot move it. A lateral X-ray shows a thin flake of bone anteriorly between his tibia and his femur. The AP view may look almost normal. This injury is worse than it looks, because much translucent cartilage may be pulled up with the small bony fragment. The diagnosis is often missed. If the loose fragment remains caught in his knee, he will lose the last 10° of full extension.
FRACTURES OF THE TIBIAL SPINE Aspirating blood from
the child's tensely swollen knee joint will immediately relieve
his pain. Anaesthetize him and try to extend his knee fully.
This will not reduce the fracture completely, but you can
usually reduce it enough to permit full extension.
If you cannot fully extend his knee, refer him.
If you can extend his knee, hold it in full extension (not overextended) and apply a plaster cylinder (79.2) from the upper part of his thigh to just above the heads of his metatarsals. Allow him up immediately, and teach him to walk as naturally as possible. Leave the cylinder on for 6 weeks. Knee movements will then return gradually as he uses his leg.
If he presents late, and you cannot extend his knee, even under anaesthesia, refer him for open reduction.
80.7 Avulsion of the tibial tuberosity
During childhood a projection of the proximal tibial epiphysis forms the tibial tuberosity and the attachment of the patellar tendon. At any age until early adult life when the epiphysis unites, sudden contraction of a child's quadriceps may tear his tibial tuberosity away from his tibia.
AVULSION OF THE TIBIAL TUBEROSITY Treatment depends
on the degree of separation.
If separation is mild, immobilize the child's knee in extension in a plaster cylinder for 4 weeks.
If separation is severe, anaesthetize him, try to push his tuberosity back into place, then apply a plaster cylinder in extension.
If closed reduction fails, refer him for open reduction.
80.8 Displacement of the proximal tibial epiphysis
Treat this rare injury in the same way as displacement of the lower tibial epiphysis. Study the X-ray carefully, and try to push the child's displaced epiphysis back into place. If his epiphyseal line is crushed (a Salter Harris Type V lesion, Fig. 69-8), a severe deformity will develop that will later need osteotomy.
