Fractures in the Immature Foot

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June Reed
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1 Fractures in the Immature Foot Kaye E. Wilkins, M.D. Clinical Professor Orthopaedics & Pediatrics University of Texas Health Science Center at San Antonio San Antonio, Texas (210)

2 FRACTURES IN THE IMMATURE FOOT INCIDENCE Fractures of the foot in children are rare. The foot and ligamentous structures are very flexible - thus, the forces are often transmitted proximally to the tibia and femur (FIGURE 1). When they do occur, fractures in the pediatric foot are usually simple and require very little active treatment. Some fractures do require active intervention such as fractures of the: talus, calcaneus, navicular, tarsal metatarsal fracture dislocations, 5 th metatarsal base and shaft, metatarsal neck fractures, and great toe avulsions. 2

3 FRACTURES OF THE TALUS Fractures of the Neck These are rare in children. The adult to children ration is 10:1. The mechanism is usually a forced dorsiflexion of the neck of the talus against the anterior lip of the distal tibia. The head and neck remain pronated but are dorsally displaced and abducted (FIGURE 2). The diagnosis is usually made with the radiographic technique of Canale and Kelly which delineates the anterior-posterior outline of the neck of the talus. 4 This view is taken with the foot pronated 15 and the x-ray tube angled 75 to the table-top. This view separates the talar neck from the underlying calcaneus. 3

4 In treating these fractures, if they are nondisplaced, cast immobilization and nonweightbearing until they are healed is usually sufficient. Displaced fractures usually require a manipulative closed reduction which involves reversing the deformity by 4

5 plantar flexing and supinating the forefoot (FIGURE 3). The acceptable limits of reduction are less than 5mm displacement and less than 5 of malalgulation. If one is unable to achieve satisfactory closed reduction, the fracture must be reduced surgically. In the anterior approach the safe interval is between the extensor hallicus longus and tibialis anterior. The surgical dissection should be kept to a minimum. Internal fixation has no proven effect on preventing avascular necrosis but is felt to hasten union. The complications include avascular necrosis which can occur as high as 30% even in undisplaced fractures. Weightbearing probably has no effect upon the 5

6 development of avascular necrosis. Weight bearing should be allowed when the fracture is healed or when the technicium scan has become nonreactive. Fortunately, a crushed, deformed talar dome may produce a reasonable function in the child. Fractures of the Lateral Process This is a fracture of the area of the talus which involves both the fibular-talar and subtalar joint. It often is misdiagnosed as an ankle sprain. Treatment usually consists of open reduction and internal fixation if the fragment is large enough or excision if it is small. Transchondral Fractures (Dome) Early radiographs may be negative and thus require bone scan or MRI for the diagnosis. 1 There are two types which include: posteromedial lesions produced by inversion and plantar flexion of the foot with external rotation of the tibia. The anterolateral lesions are caused by inversion and dorsiflexion and may have an associated rupture of the fibular collateral ligament system. 2 Canale and Belding doubted that the medial lesions were traumatic in origin. 3 It is felt that surgical excision gives better results if the lesions are symptomatic. The 6

7 anterolateral lesions can be removed directly. The posteromedial lesions may need to have an osteotomy performed of the medial malleolus to reach the posterior location on the dome. Recently, Greenspoon and Rosman described a technique of bone-grafting the medial lesions by approaching the talus through the non-articular medial surface. 8 FRACTURES OF THE CALCANEUS Incidence The incidence is very rare in children occurring only 1/20th that of adults. 19 It is greater in males in adolescence. The female incidence is equal through all age groups. 18 It may be a cause of an occult limp in toddlers. 20 Mechanism In children, it is less from falls but more from direct injury, that is, lawn mowers with open fractures. The child=s calcaneus is more flexible and thus less likely to crush. A fall from a height is more common in children with joint depressions (FIGURE 4). More often, children have other associated injuries with the fracture of the calcaneus. 7

8 Diagnosis Often, these findings are subtle on x-ray. 7,21 It requires a minimum of 4 views (lateral, axillary, dorsoplantar, oblique dorsoplantar) to visualize adequately the fracture on plain x-rays. 18 In infants with normal radiographs, radio nucleotide scan imaging or MRI may be helpful. This may be another type of the so-called Atoddler@ fractures. 20 To adequately evaluate the articular surface of the subtalar joint, CT scans are very helpful. 6,16 In those patients sustaining a fall from a significant height, the physician should always check the lumbar spine for an associated compression fracture. 8

9 Classification Schmidt and Weiner describe three groups. 19 First there is the extra-articular which involves mainly the body of the calcaneus and the nonarticulating surface. This is more common in the younger child. Secondly, there is the intra-articular which usually is due to a fall from heights and is more common in older children and adolescents. In this one, the articular surface is depressed. Finally, there is the loss of bone with the loss of the achilles tendon insertion which is usually associated with some type of open laceration, i.e., lawn mower injuries. With the event of CT scans, Cosby and Fitzgibbons described three groups of diaplacement of the articular surface. 6 This classification is useful in determining outcomes of non-operative treatment. In Type I, these are small fractures and are not displaced less than 2mm. These usually do well with nonoperative treatment. In the Type II, the articular surface is displaced greater than 2mm and can be treated nonoperatively but may have poorer results than Type I. In Type III, these fractures are comminuted with multiple small fragments and do poorly even with operative treatment. Management 9

10 In the younger individuals remodeling may correct with minor joint incongruities. Thus, the patient is treated non-weightbearing until the fracture is healed. In the older child with joint depression, the fracture must be treated with open reduction and internal fixation using a lag screw via lateral approach. FRACTURES OF THE NAVICULAR Fractures of the navicular in children are rare and often may be missed. They may even be recognized only on a CT scan. If there is much incongruity of the joint surface, surgical reduction may be required. FRACTURES OF THE CUBOID These are often overlooked. They are often called a Anutcracker@ fracture because they are due to compressive forces of the cuboid between the calcaneus and the two lateral metatarsals. 9 If a cuboid fracture is present one must always check for associated tarsal metatarsal disruptions. If the lateral cortex is incongruent, this can disrupt the function of peroneus longus as it courses through its adjacent sheath. 17 This fracture also has been described as occurring as a stress fracture in infants who toeout

11 TARSAL-METATARSAL FRACTURE DISLOCATIONS Anatomical Factors In this area, the ligaments are stronger on the plantar aspect. The second metatarsal is recessed in its articular surface which makes it more stable. Mechanisms There are two mechanisms that account for this fracture pattern. The first is due to flexion-abduction forces which produces a fracture in the base of the second metatarsal and crush fracture of the cuboid. The second involves violent plantar flexion in which the foot is loaded in a tiptoe position resulting in rupture of the weaker dorsal ligamentous structures. Treatment The undisplaced fractures (less than 2mm) can usually be treated conservatively with elevation and a compression dressing. The displaced fractures may require a closed reduction in which Chinese finger-trap traction is applied to the toes. These may require medial and lateral pins to stabilize the fractures. Some, if they are markedly displaced, may require open reduction with pin fixation. 11

12 METATARSAL FRACTURES Fifth Metatarsal Fractures of the base of the fifth metatarsal (metaphyseal) are seen in the younger age group. One must differentiate this fracture from the apophysis. The apophyseal line is usually is parallel to the metaphyseal shaft whereas the metaphyseal fracture line is perpendicular to the metatarsal shaft. This is not a true avulsion fracture by the peroneus brevis. The fracture occurs because of greater integrity of the ligamentous insertion between the metatarsal and cuboid than the metaphyseal bone. Treatment. Usually these are immobilized only for comfort. Warn the parents beforehand that this fracture may be slow to heal completely or that the fracture will also have some late displacement. Neither condition of which is of any functional or cosmetic significance. Diaphyseal fractures are usually seen in older teenagers. This is the true AJones@ fracture in which there is very slow healing. This usually requires stabilization with a screw placed axially up the intramedullary canal. 12

13 Stress Fractures These manifest by the classical signs of increased pain with activity, decreased pain with rest. X-ray changes may not occur for 3-4 weeks. It needs to be remembered that stress fractures can occur in young children as well. 5 If it is a diaphyseal fracture, union may be delayed even with stress fractures. Osteochondral Fractures of the Metatarsal Head These are often missed. They interfere with extensor tendon function and may be painful. Excision is usually the treatment of choice. Fractures of Metatarsal Shafts These are usually the result of a direct blow to the foot. Thus, soft tissue injury often is a major factor. Fasciotomies may be necessary. Metatarsal Neck This is the result of bending forces distally on the metatarsal area. Closed reduction is usually accomplished by finger-trap traction followed by application of a 13

14 well-moulded cast. It must be remembered that bayonet apposition is acceptable as long as there is not significant dorsal or plantar angulation. Open reduction is done via a dorsal approach in which the pins are inserted distally, then retrograded proximally into the shaft. The most common complication is growth arrest which can occur if the distal physis is involved. PHALANGEAL FRACTURES These are usually simple fractures treated by closed reduction with buddy taping. The one exception in which operative management is required is an avulsion of the proximal phalanx of the great toe by the collateral ligament. If there is significant displacement of the collateral fragment, open reduction may be required. COMPARTMENT SYNDROMES Unfortunately, this is often unrecognized early. This entity must be suspected in those injuries that have a significant crushing mechanism. The clinical findings 12 include sensory loss of 50%. Pain on passive dorsiflexion of the toes is the most reliable clinical sign. Compartment pressure measurement will help make the diagnosis. Measurements greater than 30 mm Hg. indicate abnormal compartment pressures. It 14

15 must be remembered that intra-articular calcaneal fractures can increase the pressure in the central plantar muscle compartment. Unrecognized compartment syndromes in the foot can lead to claw toe deformities. 11,13 Fasciotomy is the treatment of choice and must include both dorsal interosseous and plantar compartment 15

16 REFERENCES 1. Anderson, I.F.; Crichton, K.J.; Gratlan-Smith, T., et. al.: Osteochondral Fractures of the Dome of the Talus. J. Bone Joint Surg., 71A: , Berndt, A.L. and Harty, M.: Transchondral Fractures (Osteochondritis Dessicans) of the Talus. J. Bone Joint Surg., 41A: , The most complete review of the types, mechanisms of injury and treatment of this injury in the orthopedic literature. Differentiates medial from lateral injuries. Found conservative management gave as poor results in children as in adults. Describes four states in these injuries. 3. Canale, S.T. and Belding, R.H.: Osteochondral Lesions of the Talus. J. Bone Joint Surg., 62A:97-102, Reviewed 29 patients and found lateral lesions associated with trauma and more likely to be symptomatic. Medial lesions often were less symptomatic. Gives treatment recommendations using Berndt and Harty classifications. 4. Canale, S.T. and Keely, F.B.: Fractures of the Neck of the Talus. Long term Evaluation of 71 Cases. J. Bone Joint Surg., 60A: , One of the most extensive reviews of talar fractures. Twelve of 16

17 their cases were 16 years or younger. Described radiographic techniques of evaluation. Gave guidelines for acceptable reduction. 5. Childress, H.M.: March Foot in a Seven Year Old Child. J. Bone & Joint Surg., 28A:877, Crosby, L.A. and Fitzgibbons, T.: Computerized Tomography Scanning of Acute Intra-articular Fractures of the Calcaneus, A New Classification System. J. Bone & Joint Surg., 72A: , DeBeer, J. D.; Maloon, S., and Hudson, D.A.: Calcaneal Fractures in Children.S. Af. Med. J., 76:53-54, Greenspoon, J. and Rosman, M.: Medial Osteochondritis of the Talus in Children: Review and New Surgical Management. J. Pediatr. Orthop., 7: , Hermel, M.B., and Gershon-Cohen, J.: The Nutcracker Fracture of the Cuboid by Indirect Violence. Radiology, 60: , Letts, R.M. and Gibeaut, D.: Fracture of the Neck of the Talus in Children. Foot and Ankle, 1:74-77, Report on 12 cases of fractures of the talar neck in children. Four 17

18 cases were younger than 3 years of age. Noted avascular necrosis in undisplaced fractures. 11. Manoli, A. and Weber, T.G.: Fasciotomy of the Foot: An Anatomical Study with Special Reference to Release of Calcaneal Compartment. Foot & Ankle, 10: , Meyerson, M.D.: Management of Compartment Syndromes of the Foot. Clin. Orthop., 271: , Mittlmeier, T.; Machler, G.; Lob, G., et al.: Compartment Syndrome after Intra-articular Calcaneal Fracture. Clin. Orthop., 269: , Three recent articles emphasizing the need to recognize and treat -aggressively compartment syndromes in the foot. 14. Mulfinger, G.L., and Tureta J.: The Blood Supply of the talus. J. Bone Joint Surg., 52B: , Describes the blood supply of the talus as coming from three sources. Points out the vulnerability of the neck to developing avascular necrosis in fractures. 15. Nicostro, J. F. and Haupt, H.A.: Probable Stress Fracture of Cuboid in an Infant. J. Bone & Joint Surg., 66A: ,

19 16. Pablot, S.M.; Daneman, A.; Stringer, D.A. and Carroll, N.: The Value of Computed Tomography in the Early Assessment of Comminuted Fractures of the Calcaneus. A Review of Three Patients. J. Pediatr. Orthop., 5: , Phillips, R.D.: Dysfunction of Peroneus Longus after Fracture of Cuboid. J. Foot Surg., 24:99-102, Rasmussen, F. and Schantz, K.: Radiologic Aspects of Calcaneal Fractures in Childhood and Adolescence. Acta Radiologica. (Diag), 27: , Schmidt, T.L. and Weiner, D.S.: Calcaneal Fractures in Children. An Evaluation of the Nature of the Injury in 56 Children. Clin. Orthop., 171: , Reviews patterns of these injuries in children. Less common injury from fall than adults. Higher incidence of injury by lawn mower or direct blows. Higher incidence of other associated fractures, fewer intra-articular fractures. 20. Starshak, R.J.; Simons, G.W. and Sty, J.R.: Occult Fracture of Calcaneus - Another Toddlers Fractures. Radiology, 14:37-40, Wiley, J.J., and Profitt, A.: Fractures of the Os Calcis in Children. Clin. Orthop., 19

20 188: , Wylie, J.J.: Tarsometatarsal Joint Injuries in Children. Pediatr. Orthop., 1: , Describes three common mechanisms of injury. Found patterns of injury similar to adult. Eighteen cases reviewed. All treated with manipulative reduction, with or without percutaneous pin fixation. Results were uniformly good. 20

Surgery-Ortho. Fractures of the tibia and fibula. Management. Treatment of low energy fractures. Fifth stage. Lec-6 د.

$Surgery-Ortho. Fractures of the tibia and fibula. Management. Treatment of low energy fractures. Fifth stage. Lec-6 د.$ Fifth stage Lec-6 د. مثنى Surgery-Ortho 28/4/2016 Indirect force: (low energy) Fractures of the tibia and fibula Twisting: spiral fractures of both bones Angulatory: oblique fractures with butterfly segment.