Limb traction is useful for reducing and immobilizing femoral shaft fractures; supracondylar and intercondylar fractures of the femur; condylar fractures of the upper end of the tibia; grossly infected or contaminated fractures of the tibia; and severe fractures of the ankle mortise with subluxation or dislocation or both. Neglected dislocations of the hip and knee, gross deformities and displacements due to traumatic, infectious, or rheumatoid conditions of the hip and knee, and deformities after poliomyelitis can all be corrected by continuous traction.
The most popular form of continuous traction of the extremities is skeletal traction (through bone). Skin traction, provided by straps of adhesive plaster applied on the skin, is generally confined to use on children, but can be helpful when transporting adults to hospital. On anaesthetic limbs, only skeletal traction should be used.
Skin traction
Equipment
See tray and equipment for Skin traction, Annex 1.
Technique
Sedate the patient (anaesthesia is unnecessary). Clean the limb with soap and water, and dry it. Prepare the skin with an antiseptic solution, preferably methylated spirit, and let it dry. If a commercial traction set (complete with adhesive tapes, traction cords, spreader bar, and foam protection for the malleoli) is not available, improvise the apparatus as described below.
Open a roll of adhesive strapping on a clean dry table and spread it with the adhesive surface up. (Use a size appropriate to the size of the patient; for an adult, a 7.5-cm wide, non-elastic tape is usually suitable.) For above-knee traction, measure a length of strapping that is twice the length of the limb from the greater trochanter to the sole of the foot (Fig. 10.1A). Add an extra 35 - 40 cm to accommodate the spreader and to leave enough space (10 - 15 cm) between the sole and the spreader to permit movement at the ankle. For below-knee traction, the length of strapping should be measured from the tibial condyles (Fig. 10.1B). For the treatment of compound fractures, traction should be applied just distal to the site of fracture and the strapping should be cut accordingly.
Place a square, wooden spreader of approximately 7.5 cm (with a central hole) in the middle of the length of strapping that you have spread on the table. Cut another length of strapping about 35-40 cm long and centre it on the spreader with the adhesive surface down. The spreader is now sandwiched between the two strappings (Fig. 10.1C).
Holding the patient’s ankle and foot, pull the limb steadily, elevating it from the bed. Instruct an assistant to hold the spreader with a loop of strapping projecting 10 - 15 cm beyond the sole of the foot. Apply the strapping to the medial and lateral sides of the limb, still elevated and held in moderate traction. Protect the malleoli, Achilles tendon insertion, and the head and neck of the fibula by placing strips of felt or cotton-wool padding under the strapping at these sites (Fig. 10.1D). For above-knee traction, the adhesive strapping should extend proximally to the groin on the medial side and to the greater trochanter on the lateral side. To avoid causing deformity due to external rotation, place the lateral strapping slightly posterior, and the medial strapping slightly anterior to the mid-lateral and mid-medial lines, respectively. Ensure that the strapping lies flat on the surface of the limb. Do nor cover the anterior border of the tibia or encircle the limb with strapping.
Now apply a crepe or ordinary gauze bandage firmly over the strapping beginning 2 - 5 cm proximal to the malleoli (Fig. 10.1E). Continue bandaging up the limb, over the strappings, up to the groin (or as appropriate to the level of traction). Elevate the end of the patient’s bed and attach a traction cord through the spreader with the required weight (Fig. 10.1F, G); this should normally not exceed 5 kg.
Fig. 10.1. Skin traction. Measuring the limb to determine length of strapping required (A); levels of tibial condyles, malleoli, and Achilles tendon (B); sandwiching the spreader between two strappings (C); applying strapping to the leg while protecting the malleoli (D); bandaging over the strapping (E); attaching traction (F, G).
Contraindications
Do not apply skin traction to a limb with abrasions, lacerations, ulcers of the skin, loss of sensation, impending gangrene, atrophic skin, or peripheral vascular disease. Skin traction is also contraindicated in the treatment of marked overriding of fracture fragments or of gross, long-standing deformities.
Complications
Possible complications include allergic reaction to the adhesive material (usually zinc oxide); blister formation or excoriation of the skin from the strapping slipping; pressure sores over the malleoli; and common peroneal nerve palsy. Most of these complications can be avoided by correct application of the adhesive strapping. The most important cause of common peroneal nerve palsy is lateral rotation of the limb, resulting in compression of the nerve at the upper end of the fibula. Avoid this by keeping the patient’s knee joint moderately flexed (up to 10°).
Skeletal traction
The best site for inserting traction pins is the metaphyseal region of a mature bone. The specific sites recommended for pin insertion, in order of frequency of clinical use, are described below (measurements are given for adults).
Proximal tibia (Fig. 10.2A, B): insert the pin approximately 2 cm distal to the tibial tubercle and 2 cm behind the anterior border of the tibia, from the lateral side to avoid the common peroneal nerve.
Distal tibia (Fig. 10.2A, B): insert the pin from the lateral side approximately 4 cm proximal to the most prominent part of the lateral malleolus. Place the pin proximal to the ankle mortise, parallel to the ankle joint, and midway between the anterior and posterior borders of the tibia. There will be resistance as the pin passes through both cortices of the tibia anterior to the fibula.
Calcaneum (Fig. 10.2C): insert the pin 4.5 cm inferior and 4 cm posterior to the tip of the medial malleolus, from the medial side to avoid damaging the posterior tibial artery and nerve or entering the subtalar joint.
Insertion of the pin through the distal end of the femur is not recommended at the district hospital.
Equipment
See tray and equipment for Skeletal traction. Annex 1.
Technique
Skeletal traction is most commonly applied through Steinmann’s pins (Fig. 10.2D) inserted under local anaesthesia. The patient should be supine. Prepare the skin with antiseptic. Infiltrate the skin and soft tissues down to the bone with 1% lidocaine (Fig. 10.2E). Make a small stab incision in the skin and introduce the pin through the incision horizontally and at right angles to the long axis of the limb. Proceed until the point of the pin strikes the underlying bone (Fig. 10.2F, G). Ideally the pin should pass through the skin and subcutaneous tissue, but not muscles.
Pins are best inserted with a T-handle (Fig. 10.2H) or hand drill. Use a mallet only to make a start in the cortex and always hammer gently. Advance the pin until it stretches the skin of the opposite side and make a small release incision over its point (Fig. 10.2I).
Dress the skin wounds separately with sterile gauze (Fig. 10.2J). Attach a stirrup to the pin, and lubricate with sterile petrolatum jelly the sire where it rotates on the pin. Cover the ends of the pin with guards (Fig. 10.2K), and apply traction (Fig. 10.2L).
Fig. 10.2. Skeletal traction through bone. Sites for insertion of Steinmann’s pins in the proximal and distal tibia (A, B) and in the calcaneum (C); Steinmann’s pin, introducer, chuck, and stirrup (D); infiltrating tissues with local anaesthetic (E); making an incision and inserting the pin (F-I); dressing skin wounds, attaching the stirrup, and covering the ends of the pin (J, K); applying traction, with the leg supported by a sling (L).
As a rough guide, 1/10-1/7 of the body weight provides adequate traction, though this will also depend on the degree of displacement of the fracture and the musculature of the limb. Traction must always be opposed by counter-traction, which can be provided by the weight of the patient’s body, by elevation of the appropriate end of the bed some 10 - 20 cm, or by placing a Thomas splint against the root of the limb (see pages 93-94).
When a Thomas splint is used, traction will be more comfortable if the limb is supported by pillows or pads, which also prevent posterior sagging of the fracture fragments.
Complications
Infection of the pin track is a common complication. Clinically the skin is inflamed; the wounds are moist; percussion over the bone elicits tenderness; and the pin becomes loose. If the infection is not controlled by repeated dressings and antibiotics, remove the pin and employ an alternative method of traction. If the bone is osteoporotic and the traction too heavy, the pin will cut through the bone. Accurate insertion of the pin avoids complications from damage to the neighbouring neurovascular bundles and from penetration into a neighbouring joint. Prevent possible stiffness in the joint or contractures of tendons by repeated active and assisted exercises.
