ASSESSMENT

The acute fracture usually presents with a history of trauma and pain, swelling, and tenderness. Deformity may not be present if the fracture is not displaced. A careful clinical examination to assess areas of point tenderness will make the interpretation of radiographic findings easier. In the child, palpation should begin a distance away from the suspicious area and move slowly toward the affected site.

Plain films are the mainstay in the radiographic assessment of these injuries and should be performed first. Two views taken at 90 degrees to each other are standard. Long-bone films should include the joint above and below the site of injury to avoid missing a dislocation or a second fracture at a distance from the more obvious one. Remember, two fractures often occur in the same extremity; the proximal one is most often missed. Comparison radiographs of the opposite limb are taken any time there is confusion with normal anatomy, especially in the child. Oblique views may be helpful in uncertain cases. Never accept inadequate radiographs. Evaluate the whole picture, and always look for a second injury.

Special studies are required on occasion. Computed tomographic (CT) scanning provides excellent bone visualization. Magnetic resonance imaging (MRI) provides better assessment of soft tissues. Bone scanning can detect subtle bone injuries, but very often, simply repeating plain films, sometimes adding oblique views, 2 weeks after an injury may reveal abnormalities in the patient whose initial films appeared normal. (By this time, the fracture line may become more apparent because healing has occurred.)

Among the fractures most commonly missed on initial examination are those involving the scaphoid, the talar neck, the radial head, and the tibial plateau. In addition, the Lisfranc injury in the foot and the undisplaced growth plate fracture may not always be obvious. Finally, a lumbar compression fracture often occurs in conjunction with an acute calcaneous fracture, but may not be recognized initially unless a search for it is made. (The heel fracture is usually so painful and apparent that the patient may not appreciate the back injury until moving around.) Each of these injuries is discussed in subsequent chapters.

INITIAL CARE

All major long-bone fractures should be splinted before the patient is transported. Careless handling of the extremity that further damages the soft tissue should be avoided, but it is wise to correct any significant rotational or angular misalignment before applying a splinting device. This is done by gentle traction in the long axis of the limb. However, do not pull the protruding bone ends of an open fracture back into the wound. If this happens, be certain the surgeon is made aware that the fracture was compound.

A variety of splinting devices are available that make transfer of the patient more comfortable (Fig. 2-6). Their use should be only temporary, however, until the diagnosis is confirmed roentgenographically. These splints should not be kept on more than a few hours, and certainly not overnight. They are very uncomfortable and are not meant for extended use. They fit poorly and do not allow for proper care of the soft tissue and control of swelling.

Fig. 2-6 A and B, “Universal” temporary splints used for emergency transfer. (Unfortunately, universal splints do not fit anyone well.) These devices should not be used for more than a few hours. They become very uncomfortable after a short while.

If definitive treatment of the fracture is to be delayed, a bulky, well-padded soft dressing supplemented with plaster splints, sometimes called the “Robert Jones” dressing, should be applied (Fig. 2-7). This dressing is made by first applying several layers of cast padding or cotton roll circumferentially to the extremity. Plaster splints may then be added, and the entire dressing is secured with gauze or elastic bandage. Precut padded plaster splints should not be used alone without first dressing the limb circumferentially in several layers of cast padding. Remember: the treatment of the soft tissue is as important as the protection of the fracture.

Fig. 2-7 A well-padded bulky dressing reinforced with plaster splints should be applied as soon as possible. Start with many layers of cast padding, because this dressing is temporary and is designed to control swelling and maintain fracture position. After padding is applied, plaster or fiberglass splints are added, and the splints are secured with an elastic bandage or roller gauze. An elastic bandage alone should never be used. It does not immobilize nor “reduce” swelling. It may, in fact, do more harm by further compressing the already compromised lymphatic and venous drainage systems. Short arm splints should be well padded around the wrist. Otherwise, the wrist and hand may “hang” over the edge of the plaster and pain may result.

The extremity is then elevated above the level of the heart, and ice is applied to control swelling. The neurologic and circulatory status of the extremity distal to the injury should always be checked and recorded (Table 2-1). A complete neurologic examination is usually unnecessary. If the patient can extend the thumb and flex and spread the fingers, the major nerves (radial, median, and ulnar) of the upper extremity are functioning; if the patient can flex and extend the toes, the major nerves (posterior tibial and peroneal) to the lower extremity are intact. If a neurologic or vascular impairment is present, it is often relieved by reduction of the fracture or dislocation. If a neurologic impairment persists following the reduction, it is usually treated by simple observation and exercises to prevent contractures. The prognosis is generally good for complete recovery. Circulatory impairment that persists requires immediate vascular evaluation. The initial neurologic examination is particularly important because if a deficit is discovered only after treatment, it may not be able to be determined whether it was present before or occurred as a result of treatment.

Table 2-1 Occasional Neurovascular Complication of Common Injuries

THE ELEMENTS OF CLOSED REDUCTION

Most common fractures can be treated by manual reduction and immobilization, but for this procedure to be successful, certain mechanical aspects of the fracture should be understood. Whenever a bone has been broken and the fractured ends separate, the soft tissue (mainly periosteum) on the side opposite the direction of displacement ruptures and allows the fracture to angulate and rotate (Fig. 2-8). The tissue on the side to which the displacement occurs remains intact, although it may be stripped off of the bone. This intact soft tissue forms a “hinge” that can be used in the treatment of many fractures to help guide the displaced distal fragment or fragments into place and to help maintain that position.

Fig. 2-8 A typical fracture with an intact “periosteal hinge” on the concave side.

Many methods can be used to place bones back into their original position. Most of these require that the distal fragment be placed into apposition to the proximal one. Some fractures require only a “push” back into place (Fig. 2-9). Others need a more complicated maneuver that incorporates traction and manipulation of the fragments (Fig. 2-10). The nature of the fracture and its displacement determine which method is necessary.

Fig. 2-9 A, An epiphyseal fracture that simply requires that the distal fragment be gently pushed back into place. B, A transverse fracture that may be reduced by simple traction. C, An oblique “toggle” type of fracture that will require a more complicated manipulation. Even though the fracture fragments are not shortened, they must be angulated to accomplish the reduction. Simple traction would only tighten the soft tissue hinge and prevent reduction of this fracture.

Fig. 2-10 A, Typical Colles’ fracture. B, The distal fragment is disimpacted, and the deformity is increased. Thumb pressure and traction are applied. C, The distal fragment is pushed distally to reduce the dorsal cortex. D, The reduction is completed by volar pressure and held with three-point cast molding (arrows) to keep the soft tissue hinge tight.

Before any reduction is attempted, each fracture should be thoroughly studied and a complete mental plan developed. This plan should include every detail in the manipulation, including where the operator will be positioned, how the extremity will be grasped and held, and where the assistant should be positioned. In general, most reductions are accomplished as follows: (1) a variable amount of traction is applied to the distal fragment with countertraction on the proximal fragment; (2) the deformity is increased, if necessary (reproduce the injury), and rotational misalignment is then corrected; (3) the distal fragment is then reduced and the angular deformity corrected. The periosteal hinge will usually prevent overreduction. A cast is then applied to hold the position. The cast should be properly molded to prevent recurrence of the deformity in the cast by keeping tension on the soft tissue hinge and prevent recurrence of the deformity in the cast (see Fig. 2-10, D). Even casts that are applied to undisplaced fractures should be molded to avoid the loss of position that occasionally occurs in spite of protection (Fig. 2-11).

Fig. 2-11 A, An undisplaced fracture of the distal radius treated with a loosely fitted cast. B, Marked posterior angulation present at the time of cast removal. (Fortunately, the deformity was expected to correct with growth.)

Utilization of this manipulative method and the soft tissue hinge applies only to transverse or short oblique fractures that are stable after their irregular bone ends are engaged. It does not work with long oblique or spiral fractures or with markedly comminuted ones, because their ends cannot be engaged to prevent shortening.

Questions often arise as to what constitutes an adequate reduction. In general, the following principles are valid:

ANESTHESIA

Adequate anesthesia can usually be obtained by direct infiltration of the fracture hematoma on the extensor side under sterile conditions with 5 to 10 mL of a local anesthetic. If a local anesthetic is to be used, the procedure should be undertaken soon after the injury. Otherwise, the hematoma may clot, and the anesthetic will not spread through the fracture as well. Regional anesthetics are also helpful because they eliminate the need to add more volume of fluid to an already swollen area. Digital or metacarpal blocks work well for finger fractures. General anesthesia is often necessary, especially in children.

The intravenous or Bier block is useful in forearm and wrist fractures, although the movement of the extremity required to perform the block is sometimes uncomfortable. An intravenous line is always established in the other upper extremity in the event of a complication. Light sedation is administered. A small needle is then inserted into an appropriate distal vein on the injured extremity, and a double tourniquet is applied to the upper portion of the limb. The extremity is then exsanguinated up to the tourniquet with an elastic wrap or, if this is painful, simply elevated for 3 minutes to empty the venous system. The proximal tourniquet is then inflated above the systolic blood pressure, and any elastic wrap is removed. The venous system is then filled, depending on the size of the patient, with 30 to 50 mL of a 0.5% solution of lidocaine mixed with nonbacteriostatic normal saline. The needle is then removed from the involved extremity. After a few minutes, the fracture can be manipulated. If the proximal tourniquet becomes painful, it can be released after the lower one has been inflated because the lower tourniquet is now in an area that has adequate anesthesia.

After the procedure has been completed, the tourniquet is slowly and intermittently released to avoid the undesirable central nervous system (CNS) and cardiovascular side effects that occasionally occur when the anesthetic enters the general circulation. These are early CNS irritability followed by sedation. Seizures, tremors, and bradycardia have even rarely been reported. Both tourniquets should not be released until at least 20 minutes have passed after the lidocaine injection, even if the procedure takes less time.

EXTERNAL IMMOBILIZATION

Casts are applied for three reasons: (1) to immobilize the ends of a fracture, (2) to allow ambulation, and (3) to hold the position of reduction. A cast never completely immobilizes a fracture. If properly applied, however, it provides enough relative immobilization to allow the fracture to heal. A variety of materials are available for casting. Plaster of Paris is easy to manipulate, has a long shelf-life, and is relatively low in cost. Synthetic casting materials are becoming increasingly popular because of their light weight and strength. Also, less material is usually needed than for plaster. However, a disadvantage for the generalist using these materials is that they have a relatively short shelf-life (2 to 3 months in some cases), and they are also more expensive. When storing synthetic materials, be certain to turn the packages occasionally so that the material does not become dry. Commonly used materials are 2-, 3-, and 4-inch stockinette; 3- and 4-inch cast padding; and 2-, 3-, 4-, and 5-inch plaster or Lightcast rolls.

Some physicians occasionally prefer splints (usually anterior and posterior) to circular casts as primary care to avoid possible circulatory and swelling complications. These splints are sometimes called “sugar tongs” if the units are continuous. The splint system, shaped like an elongated U, is held in position by gauze or an elastic bandage (Fig. 2-12). It can be easily loosened or tightened if needed. Always apply cast padding to the limb first.

Fig. 2-12 The sugar tong splint. It is made from a long continuous piece of padded plaster or fiberglass splint material, usually 3 or 4 inches wide, and extends from the palm around the elbow to the dorsum of the hand. Always apply circular cast padding around the limb first. Roller gauze or elastic bandage is applied over the splint to secure it in place. Similar splints can be used to stabilize ankle injuries and even humeral fractures.

Whenever a cast is used, the extremity should always be held in the position of function while the cast is being applied, unless the extremity must be positioned otherwise, such as for maintenance of fracture position (Fig. 2-13). Casts are always applied in the same orderly sequence. The assistant holds the extremity in the proper position, and a single layer of stockinette, although not always necessary, may be applied (Fig. 2-14). Cast padding is then applied, beginning at one end and proceeding to the other to a double thickness by overlapping the roll 50% each turn. Do not overpad because the cast will be loose, but do place “donut” pads over bony prominences or other areas of concern (peroneal nerve at the fibular neck, ulnar styloid, both malleoli, and the olecranon process).

Fig. 2-13 Proper joint positions for casting. A, The ankle is in too much equinus. B, If the position is changed to the proper position of 90 degrees after the padding or plaster has been applied, a painful cast ridge may develop. C, Proper position and length of the short arm cast. Note that the metacarpophalangeal joints should be able to be completely flexed to a right angle and the cast should not extend beyond the distal palmar crease or too far down on the small finger. The patient should also be able to fan the fingers. The elbow joint is usually casted at 90 degrees and the knee at 30 degrees if they are included in the cast. All short leg walking casts should be long enough to include the plantar aspect of the metatarsal heads.

Fig. 2-14 The cast. A, A stockinette may first be applied. Any folds in front should be trimmed. B, Beginning at one end, cast padding is added while overlapping each roll by half. C, The plaster is removed from the water after the bubbles cease. The ends are pinched shut, and the roll is gently squeezed to expel excess water. Less water or excess wringing causes faster drying. Using the larger sizes may help avoid premature drying of the roll. Wet plaster makes a smoother cast. D, Beginning at one end, the plaster is pushed onto the extremity by using gentle pressure by the thenar eminence against the middle of the roll. The roll should remain in contact with the limb and is usually not lifted from it. Additional rolls are started where the last one ended. The roll is applied so that the opening side faces the operator and not the extremity. Rolling is continuous, and each layer is rubbed so that all layers fuse together. The short leg cast should always extend under the metatarsal heads for support. E, Tucks or pleats are taken as often as necessary to guide the roll and to accommodate any tapering of the limb. The stockinette is folded back and incorporated into the cast. F, Reinforcing splints five to ten layers thick applied to the sides or back add a great deal of strength without adding much weight. They are particularly useful at the ankle, where the cast is weakest and breakage is most common. G, The cast is molded with the flat surface of the hands, if necessary, and trimmed, especially at the small toe. H, Cast boots function better than walking heels; there are fewer repairs and a better gait. Wait 48 hours for the cast to cure before allowing weight bearing on plaster (1 hour for lightcast). I, Roentgenogram of a portion of a short arm cast showing a cast of even thickness without excessive padding between the cast and the skin. J and K, Casts are removed with the cast saw and spreader. The cast is removed by cutting down through both sides. Do not saw back and forth with the blade. It is better to pick the blade up and move it every time the plaster is cut through. Counterpressure with the thumb and/or index finger on the cast will prevent the blade from injuring the underlying skin. Cut the cast at right angles to the material. Sharp blades cut easier with less force and therefore less potential for skin injury. A hot blade may mean a dull blade. While cutting, the cast may be pulled or pushed away from the skin to give more room. Edema that holds the limb against the cast or the presence of soft rheumatoid skin may increase the chance of the cast saw abrading the skin. L, The sectioned cast showing even, fused plaster that is properly contoured and molded. It is as thick at the end as it is in the middle. The use of wider rolls will result in a more even cast than the use of many small rolls. Two 4-inch rolls of plaster will suffice for an adult short arm cast (or two 2-inch rolls of Lightcast). Three 6-inch rolls are necessary for an adult short arm cast (or three 4-inch rolls of Lightcast).

The plaster roll is then placed in lukewarm water and left until the bubbling ceases. Plaster sets more slowly in cold water, thus allowing more time to work. Warmer water causes plaster to set more quickly. Never use hot water. After removal from the water, the ends of the plaster are pinched together, and the roll is gently twisted. This removes some of the water but not the plaster. The plaster roll is then applied to the limb in the same manner as the cotton was; that is, starting at one end and going up and down the extremity while overlapping by 50% each turn. Moderate tension is used during the application, with greater tension being used on the proximal fleshy part of the extremity. Tucks or pleats are taken frequently to allow the plaster to be smooth and even on parts of the extremity that taper. This also avoids ridges or transverse creases. The roll is applied by pushing it with the thenar eminence and should be kept close to or on the extremity at all times.

The cast should be of uniform thickness, about 0.6 cm. No two turns should be made at the same spot, except at the ends of the cast. Thus, the plaster is applied evenly end to end and will not be any thicker at the fracture site than elsewhere. Each layer should be applied moist to allow each turn to bond to the next layer. If this does not occur, a cast results that is several individual layers thick rather than one single thickness. The plaster should be worked and smoothed during the application of each layer.

While the plaster is setting, it is contoured and molded with the flat of the palm or thenar eminence to apply the proper three-point fixation. Overzealous rubbing while in the late drying phase may cause the plaster to crumble while it is setting.

Lightcast is easier to apply, because tucks and reinforcing splints are not necessary. Always wear gloves because the bonding material adheres to the skin and is difficult to remove. Use cool water for Lightcast.

As a general rule, a cast should immobilize one joint above and below the fracture, although short arm casts are often used for wrist fractures and short leg casts for ankle fractures. Two rolls of 4-inch plaster or 2-inch Lightcast are sufficient for a short arm cast. Three rolls of 6-inch plaster or 4-inch Lightcast are adequate for a short leg cast.

If the fracture is inherently stable, the cast merely acts as a splinting device. Fractures that require reduction or those that are unstable use the cast to hold the position by maintaining three-point tension on the soft tissue hinge, two of the points being the operator’s hands that mold the cast into a flat appearance. The third point is a wide area of the proximal portion of the cast. It is unnecessary to apply direct pressure there.

Although fiberglass can withstand water, the cast cannot become wet because the padding will hold water and the skin will macerate. There is, however, a very effective waterproof cast liner available; it comes in rolls and allows the Lightcast to be submerged in water. The liner is applied instead of the stockinette and cast padding. It is rolled on in the same manner as cast padding, overlapping 50% to have a double thickness. Lightcast is then applied in the usual fashion. The liner works best with short arm casts. When used with short leg casts, the material sometimes rolls up at the heel, making walking uncomfortable. After the patient swims or bathes, the water drains out as a result of gravity. Most casts will be dry in 30 to 60 minutes. If the cast has been in salt water or chlorinated water, it should be rinsed and then allowed to dry. Some skin changes do occur because of moisture, but they are usually minor. The cast may be slightly more difficult to remove over the liner because it does not “pop” apart quite as easily. Overall, patients are pleased with the liner, especially younger and more active ones.

AFTERCARE

After cast application, the extremity is elevated above the horizontal level of the heart, and ice is applied for 48 to 72 hours. The patient is closely observed for signs and symptoms of circulatory obstruction or acute compartment syndrome. (Excessive pain may be the only early clue.) Hospitalization may even be necessary in some cases. The cast must be split and spread at the earliest sign of circulatory embarrassment. If discomfort secondary to swelling is the only problem, spreading the plaster alone is usually sufficient, but if there is concern for the circulatory status of the extremity, the entire cast, cotton, and every bit of stockinette should be split completely down to the skin and spread apart. If the problem persists, the entire cast should be removed, although this is usually unnecessary.

Plaster splits more easily to relieve swelling than Lightcast does. It needs to be cut on only one side and spread. The opposite side will usually crack and keep the split open. Fiberglass must be cut slightly on the opposite side. Otherwise, it springs back.

It is often difficult to differentiate among fracture pain, acute compartment syndrome, arterial injury, and nerve palsy, especially in an anxious patient. Peripheral nerve testing will usually rule out nerve palsy, and if peripheral pulses are present, arterial injury is unlikely. The acute compartment syndrome is a condition that develops when perfusion of nerve and muscle decreases to the point where it is unable to sustain viability. Pressure inside the natural fascial compartments of the arm or leg may rise, usually because of fracture bleeding, which then obstructs venous outflow. This leads to a further increase in tissue pressure and necrosis, sometimes within a few hours. A compartment syndrome should be suspected if there is (1) pain on passive stretching of the muscles of the affected compartment, (2) paresthesias or sensory loss, and (3) tenseness of the involved compartment. Paralysis may also occur. Arterial injury or compartment syndrome secondary to swelling in a tight cast could lead to Volkmann’s ischemic contracture if untreated (Fig. 2-15). This is a rare complication and most commonly occurs after severe elbow injuries, high tibial fractures, and metatarsal fractures. It is considered a surgical emergency.

Fig. 2-15 Drawing of a typical Volkmann’s ischemic contracture. Contractures and severe muscle loss are the usual end result. The deformity often persists despite prolonged attempts at reconstructive surgery and therapy.

Movement of all joints that are not immobilized is encouraged as soon as possible. Fewer vasomotor disturbances, less swelling, and a faster recovery will result. Painful pressure sores may develop rapidly under a cast. Remember: the pain will subside when tissue necrosis has occurred. These pressure areas, although rare in a properly padded cast, should be treated or at least evaluated before skin necrosis occurs. If a “window” must be cut in a cast to assess the status of the skin or the cast must be split, the window and padding should always be replaced to prevent edema of the soft tissue from swelling through the hole or the split section. If a cast has been properly applied, it should not require changing during the course of treatment, even after swelling subsides. If the cast telescopes, however, and there is danger of losing the position of the fracture, it should be changed.

Itching beneath the cast is common. It can sometimes be controlled by ice or over-the-counter antihistamines or by blowing warm air into the cast with a hair dryer. The use of any instrument to scratch the area, such as a coat hanger, should be avoided. The cast can be covered with a stockinette to keep it from snagging clothing. It can be kept dry during bathing by wrapping it with a plastic trash bag and avoiding the main flow of the shower. If the cast becomes slightly wet, it can be dried with a hair dryer. If the cast is too wet, it will need to be changed.

Ecchyhmosis, which may alarm the patient, may become visible in a few days either distal or proximal to the site of injury because of the migration of blood by dependent drainage through the tissue planes. Commonly, the toes become bruised in appearance with ankle fractures and the fingers with wrist fractures.

Roentgenograms are repeated at weekly intervals for 2 to 3 weeks mainly to assess the position of the fracture. Healing changes may not be visible for some time. The length of time required for complete healing varies with the age of the patient, the nature and site of the fracture, and the specific bone involved. As a rule, fractures in children and fractures near the ends of the bone (metaphysis) heal more rapidly than do those in the relatively avascular midshaft (diaphysis). Long spiral fractures also heal more quickly than transverse shaft fractures because a larger area of bone is available.

Fracture healing is a clinical judgment, and the determination as to when a cast may be removed is not made on the basis of the roentgenogram alone. Roentgenographic evidence of complete healing may actually lag several weeks behind true clinical union. In general, the cast may be removed when sufficient time has passed for the particular bone under treatment to heal. This varies with the type of fracture and the age of the patient. Clinical and roentgenographic assessments are made after the cast has been removed, and if the fracture has no motion and is not tender to palpation, pressure, or stress, then sufficient healing has probably occurred to allow the cast to be left off. If any doubt exists, a removable protective splint may be applied for 2 to 3 more weeks, and gradual resumption of activity is allowed. If motion, tenderness, or swelling is present, suggesting a slow or delayed union, another circular cast or protective splint is applied, and the fracture is reassessed in 2 to 3 weeks.

NOTE: An occasional patient may become very light-headed or even pass out when the cast is removed. Always be alert to this possibility.

REHABILITATION

It is important that the patient be kept informed of the entire treatment plan from start to finish. This should include what to expect after the cast has been removed: stiffness for several weeks, swelling, callous bumps, increased hair on the arms and legs in children, or a temporary limp. These usually subside in a few weeks. It is equally important not to let the patient become active too quickly after the cast has been removed. Allow some time for the bone to regain its strength (4 to 6 weeks).

Rehabilitation is actually begun at the time of the injury by controlling excessive soft tissue swelling. Scar formation is thus diminished, and earlier normal function is the end result once the fracture has healed. As soon as possible, the patient is instructed to move any joints that are not immobilized by the cast and perform some meaningful tasks at home or work. Isometric exercises in the cast may prevent excessive atrophy.

After cast removal, active mobilization of joints that were immobilized by the cast is begun. A repetitive exercise that the patient may perform at home is preferable to most forms of physical therapy. Exercise in a swimming pool is an excellent method of restoring strength, mobility, and confidence after many injuries. Most extremities are able to regain most of their motion and strength within 4 to 6 weeks after the cast has been removed, but it is not uncommon for some stiffness, weakness, and swelling to persist longer. Formal physical therapy is usually unnecessary.

Discourage the patient from scratching the skin excessively immediately after cast removal. The skin can be somewhat tender at this time. Gentle bathing and the application of a mild skin lotion help restore the skin to normal. Some temporary increase in lower extremity swelling commonly occurs after short leg cast removal because of the loss of the soft tissue compression effect of the cast. Support hose may be needed temporarily.

A bone scan may remain positive up to 2 years after cast removal and signifies ongoing fracture remodeling and strengthening. Wait at least 2 months after cast removal before allowing most sports activities.

ADDITIONAL PRINCIPLES

PRINCIPLES OF TREATMENT

Fig. 2-16 A, Fracture of the upper portion of the humerus in a 6-year-old patient. An attempt was made to reduce the fracture, but the position could not be improved and was accepted. B, The same patient approximately 10 months later. Although the two roentgenograms are not in the same position of rotation, the remodeling and realignment are obvious.

NOTE: Remodeling is the process of smoothing off of the sharp bone ends. It occurs in adults as well as children. Only children who have growth left, however, have the ability to straighten or realign mild fracture deformities.

THE EPIPHYSEAL PLATE

Two types of epiphyses exist in growing bones: the pressure epiphysis and the traction epiphysis (apophysis). Pressure epiphyses occur at the ends of long bones and contribute to the longitudinal growth of the bone. Traction apophyses, such as the iliac crest and trochanters of the hip, contribute primarily to the contour of the bone and little to actual longitudinal growth. They are present at the attachment of major muscles and respond to traction rather than to pressure. The epiphyseal plate itself consists of several zones or layers (Fig. 2-17). The zone nearest the joint is the germinal cell layer. Moving away from the joint are the zone of proliferation, the zone of hypertrophic cartilage, and the zone of provisional calcification. Epiphyseal fractures may be categorized according to the type of injury, the relationship of the fracture line to the germinal cell layer, and the prognosis. Salter’s classification is commonly used.

Fig. 2-17 The epiphyseal plate. Most epiphyseal fractures occur through the zone of hypertrophic cartilage.

Most epiphyseal fractures occur irregularly through the weakest zone, the zone of hypertrophic cartilage. They are usually transverse and do not travel vertically across the germinal cell layer. These fractures are classified by Salter and Harris as type I or type II, and the prognosis for normal healing is good (Fig. 2-18). Manipulative reduction is usually successful. Overzealous attempts to correct minor persistent deformities during the reduction should not be made because these mild deformities usually correct themselves with growth. Further damage to the growth plate may be caused by overaggressive treatment.

Fig. 2-18 Epiphyseal fractures. A, Type I. B, Type II. C, Type III. D, Type IV. E, Type V crushing fracture. (From Salter and Harris.)

Fractures that do traverse the growth plate vertically (types III and IV) may disturb the growth, causing an angular deformity to develop as growth continues. Cross-union may even occur across the epiphyseal plate, leading to complete cessation of growth. These fractures are also frequently intraarticular, and accurate reduction is mandatory to prevent growth disturbance from occurring and to restore the joint surface. Surgery is usually necessary to accomplish these goals. Type V fractures are crush injuries that have a poor prognosis (Fig. 2-19). Frequently, no definite fracture line is visible.

Fig. 2-19 Salter type V crush fracture that resulted in a complete bony bridge (arrow) being formed in the medial aspect of the lower femoral epiphysis.