Symposium on Common Orthopedic Problems
Foot Pain in Children Richard H. Gross, M.D.*
Foot pain in children is not an unusual complaint. The evaluation of such a complaint, however, is often confounded by the fact that most pediatricians have had little exposure to this type of problem during their training. In addition, there are divergent opinions by recognized authorities on the symptomatology and management of such common problems as the pronated foot.5. 7 The purpose of this paper is to outline an approach to the child with foot pain and to offer suggestions for the management of the more common problems.
Clinical Evaluation The evaluation of the child with foot pain begins with a history and physical examination. In taking the history, it is often helpful to question the child if possible. On occasion, a parent may give the physician a history he believes the physician expects to hear, and this may be especially true when a child has flat feet. Unfortunately, even cooperative children often fail to recall stepping on a foreign' body, so that the absence of a positive history is of relative value only. The patient should be asked to localize the area of pain by pointing to it with one finger, and to describe the nature of the pain as best he can (does it ache, stab, or hurt when weight bearing, is it relieved by rest, how often does it hurt?) It is helpful to know if the pain causes any restrictions of usual activities. Are there any indications of a systemic process, such as fever, malaise, or multiple other joints involved? What measures have been taken to alleviate the pain? Has the child been seen by another physician, podiatrist, or a chiropractor? After taking the history, the physician will have an idea of the location and severity of the pain, and whether it is the patient's problem or his parents. The feet are then examined, and the approach must vary depending on whether the child is old enough to cooperate. If· the child is uncooperative, the feet are first inspected in a non-weightbearing position, as occasionally the pathology is obvious (ingrown toenail). If no problem can be detected by inspection, the child is placed in a standing position and observed during attempts to walk. The site of the pain can often be *Associate Professor, Department of Orthopaedic Surgery, and Chief of Pediatric Orthopaedics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
Pediatric Clinics of North America- Vol. 24, No.4, November 1977
813
814
RICHARD
H.
GROSS
Table 1. Common Causes of Foot Pain in Children Extrinsic III fitting shoes (ingrown toenail) Foreign body Structural Hypermobile flat foot with tight heel cord Peroneal spastic flat foot (tarsal coalition) Accessory navicular (prehallux) Pes cavus Osteochondroses (?) Inflammatory Osteomyelitis Juvenile rheumatoid arthritis Rheumatic fever Trauma Stress fracture Fractures Sprains (adolescents) . Achilles tendonitis Tumors Osteoid osteoma Ewing's sarcoma Synovial sarcoma
suspected from the part of the foot the child tries to protect (does he toe walk, or heel walk?). If he has no difficulty walking barefoot, either there is no problem or the shoes must be suspected. Compare the width of the foot to the width of the shoe. Shoes of inadequate width are one of the most common sources of pain in this age group. The child is placed in supine position on the examination table or seated in his mother's lap if cooperation is hard to obtain. The foot is examined by palpation, determining whether it is supple and the site of localized tenderness, if it exists. Palpating suspected areas of localized tenderness should always be done last. Radiographs are then obtained unless the examination indicated a cause for the patient's pain which is not of bony origin. The approach can be more direct in the cooperative child who can relate a more accurate history and indicate the site of pain. The examination should still include inspection of the foot, palpation for localized tenderness, and observation with the patient standing and walking. The shoes should be inspected in the same manner as in the younger child. If radiographs are to be made, our routine is to obtain weight bearing anteroposterior and lateral views of the foot, and an oblique non-weightbearing view. The oblique view should be included, as occult fractures are sometimes evident on these views, and it is often the only standard view on which one can detect certain bony anomalies of the foot to be described later. If the problem is in the region of the ankle joint, separate views of the ankle must also be included. Occasionally xeroradiography is helpful for the detection of nonmetallic foreign bodies. It is not unusual, however, after complete evaluation, that the etiology cannot be ascertained. As in so many instances in clinical practice,
815
FOOT PAIN
Table 2. AGES
0
TO
6
Probable Causes of Foot Pain by Age AGES
6
TO
12
III fitting shoes Foreign body
III fitting shoes Foreign body
Occult fracture
Accessory navicular
Osteomyelitis JRA (if other joints involved) Rheumatic fever
Occult fracture Tarsal coalition (peroneal spastic flatfoot) Ingrown toenail Ewing's sarcoma
AGES
12
TO
19
III fitting shoes Foreign body Ingrown toenail Pes cavus Hypermobile flat feet with tight tendo Achilles Ankle sprains Stress fracture Ewing's sarcoma Synovial sarcoma
the pediatrician must evaluate his clinical assessment to aid in deciding whether to refer the patient, Our approach is to follow the patient's progress until the problem has resolved or the etiology becomes apparent. The more common causes of foot pain in children are outlined in Table 1. Table 2 indicates which conditions are more common in different age groups.
Extrinsic Causes III fitting shoes contribute much to foot misery, and may commence almost as soon as the infant is fitted with his first pair of shoes. "Corrective shoes" used for the treatment of clubfoot, metatarsus varus, or rotational problems can result in areas of increased pressure, especially if the deformity is not flexible. An infant can only express discomfort by irritability and fussiness, and if the shoes are responsible, they should be removed instead of "breaking them in." If a foot with a rigid deformity is fitted with a stiff nonyielding shoe, it is likely that pressure sores will develop (Fig. 1). Generally, casting is safer for correction of foot deformities, although shoes may be used to maintain correction in a flexible foot. Bleck, in an excellent review of the problems related to the shoeing of children, noted that the last of most corrective shoes are molded in such a manner that they would fit an adducted foot, but not a straight foot. 2 A tennis shoe was found to come closest to the straight outline of the majority of children's feet. A child with a straight foot placed in a shoe with a swung-in leather last shoe was apt to complain of pain in the region of the little toe, where the shoe compressed the foot. Many shoes are of inadequate width in the forefoot, and with time, calluses and corns result. Nothing more than a change to a shoe withan adequate width across the forefoot is necessary. Often, tennis shoes fulfill this need better than styled leather shoes.
816
RICHARD
H.
GROSS
Figure 1. Full thickness pressure sore in the great toe in a child treated with straight last shoes for a rigid metatarsus adductus deformity. (Courtesy of Robert Hufft, M.D.)
Ingrown toenails surprisingly are more common during the second decade of life than any other time. s The entity receives much less attention in the literature than it deserves and it is certainly worthwhile to be aware of simple preventive measures. The pediatrician can spare his patients a great deal of aggravation by informing them to square off the nail when trimming, rather than rounding the edges (Fig. 2). In~ growth is enhanced when tight fitting shoes compress the soft tissues about the nail. If ingrowth is minimal, proper toenail trimming, soaks, local hygiene, and the wearing of shoes of adequate width solve the problem. For chronically inflamed nails, removal of the ungual soft tissue fold, the nail margin and matrix, or both is usually done. However, if proper nail cutting is not done postoperatively, recurrence is usual (Fig. 3). Retained foreign bodies warrant referral to an orthopedist. Localization and removal can be frustrating and are best done under ideal operating room conditions. Foreign bodies that are not radiopaque can cause great difficulty. The author has seen a patient with a chronic draining sinus of several months duration in a foot, which was believed
Normal Nail Groove
Nail
Hypertrophied Soft Tissue
c Figure 2. A, A cross section of the distal phalanx of the great toe, showing the relationship of the nail with a normal nail groove on the left and an inflamed soft tissue fold which overlaps the nail on the right. B, When the nails are trimmed by rounding off the edges, the hypertrophied and inflamed soft tissue fold can overlap the nail, and ingrowth at the distal margin will occur. C, The correct way to trim the nail is to leave the edges squared to ensure that the trimmed edge of the nail, even if incurved, will protrude distally past the soft tissue fold and ingrowth will not occur.
T FOOT PAIN
817
Figure 3. Chronically inflamed ingrown toenails after repeated unsuccessful minor surgical procedures are deformed and hypertrophied. Ingrowth and inflammation of the soft tissue folds are still present. Total excision of the nail, the nail matrix, and the tuft of the distal phalanx was necessary.
possibly to be fungal in origin after surgical exploration did not reveal a foreign body. The sinus promptly healed when a 3 cm portion of a candied apple stick spontaneously extruded from the sinus, having not been discovered at the time of previous surgery. Structural Causes Most flexible flat feet are not painful, although there is some evidence that hypermobile flat feet associated with tight heel cords can be symptomatic in adolescence. 6 This accounts for only a small percentage of patients with flat feet. If this condition is suspected, orthopedic consultation is warranted. A bony bridge between two of the bones in the mid foot or hind foot, which is defined as "tarsal coalition," can be manifest by spasm of the peroneal muscles and a rigid spastic foot that is painful on attempted motion (Fig. 4). Although oblique radiographs often demonstrate this condition, sometimes only tomography will reveal the bony bridge. If detected early, excision of the bony bar is very effective, but if secondary degenerative changes have occurred, surgery is less effective.3 If the spasm involves the posterior tibial tendon on the medial side of the foot, an accessory navicular (often called a pre-hallus) is usually found (Fig. 5A). A prominence overlying the accessory bone, often reddened from shoe pressure, is noted, and may resemble an "extramedial malleolus" (Fig. 5B). The accessory navicular is found in perhaps 10 per cent of all feet, but the majority are asymptomatic and will fuse to the body of the navicular by the time of skeletal maturity. Although this condition is classically felt to accompany a flat foot, this has usually not been the case in our experience. Again, in symptomatic feet, simple surgical excision accompanied by rerouting the tendon is very effective. Although cavus (high arch) feet have not received the widespread notorietyof the flat foot, they are generally more symptomatic and a much
818
RICHARD
H.
GROSS
Figure 4. A. Prominence of peroneal tendons at the level at the lateral malleolus is characteristic of a peroneal spastic flat foot. Attempts to invert the foot, placing these tendons on stretch, will be painful for the patient. B, Oblique view demonstrating incomplete bony bridge between the navicular and the calcaneus. At the time of surgery, there was a complete bar with cartilage in the apparent defect on the x-ray. The bony-cartilaginous bar was firm, allowing no motion. Symptomatic relief followed excision of the bar. (Courtesy of Jack Spencer, M.D.)
more significant problem for the patient (Fig. 6). Neurological disorders, especially spinal dysraphism, Charcot-Marie-Tooth disease, or Friedreich's ataxia, should be suspected, especially when the cavus is progressive or asymmetric. 9 With localized areas of weight bearing (as opposed to the flat foot, where the load is shared by a large portion of the plantar surface), calluses under the metatarsal heads are common as are claw toes. Shoe correction with metatarsal pads or bars may assist in relief, but surgical intervention usually is eventually required. The orthopedic management of these feet can be difficult, but it is probably well to involve the orthopedist relatively early in the care of cavus feet. Again, it is difficult to overemphasize the relationship of cavus feet to neurological disorders. The osteochondroses (avascular necrosis) of the bones of the foot have been felt to be a source of pain. Often the osteochondritic process is an incidental radiographic finding and is not symptomatic. The navi-
FOOT PAIN
819
Figure 5. A, Accessory navicular (arrow) is not always an obvious finding. B, Clinical appearance.
Figure 6. Clinical appearance of cavus feet. Notice the clawing of the toes and the posture of the foot, with weight bearing entirely on the heel pad and the metatarsal heads.
820
RICHARD
H.
GROSS
Figure 7. Dense tarsal navicular (right) compared with normal navicular (left) indicative of osteochondrosis of the navicular- Kohler's disease.
culat is most often involved (Fig. 7). A similar process has been described on the calcaneus, but radiographs of asymptomatic feet are indistinguishable from those felt to represent an osteochondrosis. Arch supports may be used, but informing parents of the benign natural history is most useful, and usually minimal additional treatment is required. l l A shoe elevation or a "heel cup" is often helpful in relieving symptoms in the os calcis. An exception to this general rule is Freiberg's infraction, an osteochondrosis of the second metatarsal head which can result in long-term disability. This condition does not affect children under the age of 12. There is no effective way at present of preventing deformity in this entity.
Inflammatory Causes Septic arthritis rarely involves the ankle or foot as a primary focus, except with direct contamination with a foreign body. Osteomyelitis, however, can involve the foot, especially the os calcis and talus. This condition usually presents with fever and inability to walk, with localized swelling in the hind foot. Involvement of the foot alone in systemic conditions is unusual, and this fact can be helpful in differentiating the condition from juvenile rheumatoid arthritis or acute rheumatic fever. It is also unlikely that an unilateral inflammatory process is
821
FOOT PAIN
related to a systemic cause, but bilateral involvement should mandate a careful systemic workup. Bone scanning is often helpful prior to radiographic changes of osteomyelitis. Bone aspiration or blood cultures are necessary to establish the offending organism. Present management of this entity would indicate four weeks of appropriate intravenousantibiotic therapy if treatment is undertaken. Brodie's abscess is an abortive subacute form of osteomyelitis commonly involving the distal tibia and possibly involving the small bones of the foot (Fig. 8). Adolescent males are particularly susceptible and sustain an incidence 5 times greater than the general population.5 The sclerotic bony wall of these lesions inhibits the flow of systemic antibiotics and surgical excision is indicated. Traumatic Causes With the presence of the distal tibial epiphysis in the growing child, and the relative weakness of this structure compared with bone and ligaments, the growth plate is generally first to fail with stress. It is well to remember this when evaluating what might appear to be an ankle
Figure 8.
Figure 9.
Figure 8. Brodie's abscess of the distal tibia in an adolescent male. Notice that the density of the bone is increased surrounding the radiolucent defect. Figure 9. A stress fracture of the base of the fifth metatarsal in a skeletally mature patient was not visible on the initial films, with the fracture line being visible only two weeks after the time of the original complaint. The bony margins of the fracture site have resorbed, accounting for the radiographic lucency at this time.
822
RICHARD
H.
GROSS
sprain and obtain the appropriate radiographs, as ankle sprains in children are unusua1. 10 A more complete discussion of epiphyseal injuries is available elsewhere in this volume. In the adolescent, stress fractures can occur, especially when the patient undergoes a sudden increase in physical activity, such as the start of track season. The hallmark of these injuries is localized bony pain with a negative initial radiograph, which only shows changes at 10 to 14 days when fracture callus or resorption is noted. These injuries, however, are extremely rare under the age of 12 or 13, and most commonly involve the second metatarsal. A similar problem can occur at the base of the fifth metatarsal, the prominence on the lateral side of the mid foot. Occult fractures here also can sometimes be difficult to detect radiographically (Fig. 9). Symptoms of stress fractures are often subsiding by the time of positive radiographic findings, and treatment up to this point is expectant. If the diagnosis is suspected and the patient is unable to walk, casting is probably best, and certainly does no harm even if the suspicion of stress fracture is not confirmed. Achilles tendonitis is often seen in the same type of patient who is subject to stress fracture and is probably an "overuse" syndrome, resulting in small partial tears of the tendon. The condition is diagnosed by a localized tenderness in the tendon differentiated by palpation from bony tenderness in the calcaneus itself which is a different entity. Treatment of tendonitis consists of rest, immobilization, or a combination of the two. Local injections of steroid into the tendon should never be done, as they weaken the tendon while improving symptoms, and increase the chances of subsequent complete rupture. Tumors - Tumors of the feet are rare in children, although they occur with enough frequency so that one cannot be comfortable in excluding them from a differential diagnosis. The benign osteoid osteoma can affect the small bones of the foot, causing a dull pain, especially at night. Surgical excision is curative. In general, it is not particularly important for the pediatrician to be familiar with the unusual benign bone tumors in this area, but it is important to be aware that Ewing's sarcoma and synovial sarcoma, both tumors with a poor prognosis, often involve the foot.1 Ewing's tumor can involve a somewhat younger age group, whereas synovial sarcoma has a predilection for males later in the second decade. The important aspect in diagnosis is not to ignore persistent pain or swelling. Summary A general approach to the child with foot pain has been described. In that the pediatrician is so often the recipient of parent's questions about children's shoes, it is well for him to be aware of problems relating to poorly fitting shoes, probably the most common so~rce of complaints of foot pain in children. With a systematic approach, the pediatrician is very capable of managing the majority of such complaints.
823
FOOT PAIN
REFERENCES 1. Aegerter, E., and Kirkpatrick, J.:, Orthopaedic Disease. Philadelphia, W. B. Saunders Co., 1975. 2. Bleck, E.: The shoeing of children-Sham or science? Dev. Med. Child. Neurol., 13:188, 1971. 3. Cowell, H. R: Diagnosis and management of peroneal spastic flatfoot. AAOS Inst. Course Lectures, Vol. 24. St. Louis, C. V. Mosby Co., 1975, p. 94. 4. Devas, M. D.: Stress fractures in children. J. Bone Joint Surg., 45B:528, 1964. 5. Giannestras, N.: Foot Disorders Medical and Surgical Management. Philadelphia, Lea & Febiger, 1973. 6. Harris, R I., and Beath, T.: Hypermobile flat foot with short tendo Achilles. J. Bone Joint Surg., 30A:116, 1948. 7. Inman, V.: DuVries' Surgery of the Foot. St. Louis, C. V. Mosby Co., 1973. 8. James, C. C. M., and Lassman, L. P.: Spinal dysraphism: The diagnosis and treatment of progressive lesions in spina bifida occulta. J. Bone Joint Surg., 44B:828, 1962. 9.' Lloyd-Davies, R W., and Brill, G. C.: The etiology and out-patient management of ingrowing toe nails. Brit. J. Surg., 50:292, 1963. 10. Salter, R B.: Injuries of the ankle in children. Orthop. Clin. North Am., 5:147,1974. 11. Tachdjian, M. 0.: Pediatric Orthopaedics. Philadelphia, W. B. Saunders Co., 1972. Department of Orthopaedic Surgery University of Oklahoma Health Sciences Center Box 26901 Oklahoma City, Oklahoma 73190
Foot Pain in Children Richard H. Gross, M.D.*
Foot pain in children is not an unusual complaint. The evaluation of such a complaint, however, is often confounded by the fact that most pediatricians have had little exposure to this type of problem during their training. In addition, there are divergent opinions by recognized authorities on the symptomatology and management of such common problems as the pronated foot.5. 7 The purpose of this paper is to outline an approach to the child with foot pain and to offer suggestions for the management of the more common problems.
Clinical Evaluation The evaluation of the child with foot pain begins with a history and physical examination. In taking the history, it is often helpful to question the child if possible. On occasion, a parent may give the physician a history he believes the physician expects to hear, and this may be especially true when a child has flat feet. Unfortunately, even cooperative children often fail to recall stepping on a foreign' body, so that the absence of a positive history is of relative value only. The patient should be asked to localize the area of pain by pointing to it with one finger, and to describe the nature of the pain as best he can (does it ache, stab, or hurt when weight bearing, is it relieved by rest, how often does it hurt?) It is helpful to know if the pain causes any restrictions of usual activities. Are there any indications of a systemic process, such as fever, malaise, or multiple other joints involved? What measures have been taken to alleviate the pain? Has the child been seen by another physician, podiatrist, or a chiropractor? After taking the history, the physician will have an idea of the location and severity of the pain, and whether it is the patient's problem or his parents. The feet are then examined, and the approach must vary depending on whether the child is old enough to cooperate. If· the child is uncooperative, the feet are first inspected in a non-weightbearing position, as occasionally the pathology is obvious (ingrown toenail). If no problem can be detected by inspection, the child is placed in a standing position and observed during attempts to walk. The site of the pain can often be *Associate Professor, Department of Orthopaedic Surgery, and Chief of Pediatric Orthopaedics, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
Pediatric Clinics of North America- Vol. 24, No.4, November 1977
813
814
RICHARD
H.
GROSS
Table 1. Common Causes of Foot Pain in Children Extrinsic III fitting shoes (ingrown toenail) Foreign body Structural Hypermobile flat foot with tight heel cord Peroneal spastic flat foot (tarsal coalition) Accessory navicular (prehallux) Pes cavus Osteochondroses (?) Inflammatory Osteomyelitis Juvenile rheumatoid arthritis Rheumatic fever Trauma Stress fracture Fractures Sprains (adolescents) . Achilles tendonitis Tumors Osteoid osteoma Ewing's sarcoma Synovial sarcoma
suspected from the part of the foot the child tries to protect (does he toe walk, or heel walk?). If he has no difficulty walking barefoot, either there is no problem or the shoes must be suspected. Compare the width of the foot to the width of the shoe. Shoes of inadequate width are one of the most common sources of pain in this age group. The child is placed in supine position on the examination table or seated in his mother's lap if cooperation is hard to obtain. The foot is examined by palpation, determining whether it is supple and the site of localized tenderness, if it exists. Palpating suspected areas of localized tenderness should always be done last. Radiographs are then obtained unless the examination indicated a cause for the patient's pain which is not of bony origin. The approach can be more direct in the cooperative child who can relate a more accurate history and indicate the site of pain. The examination should still include inspection of the foot, palpation for localized tenderness, and observation with the patient standing and walking. The shoes should be inspected in the same manner as in the younger child. If radiographs are to be made, our routine is to obtain weight bearing anteroposterior and lateral views of the foot, and an oblique non-weightbearing view. The oblique view should be included, as occult fractures are sometimes evident on these views, and it is often the only standard view on which one can detect certain bony anomalies of the foot to be described later. If the problem is in the region of the ankle joint, separate views of the ankle must also be included. Occasionally xeroradiography is helpful for the detection of nonmetallic foreign bodies. It is not unusual, however, after complete evaluation, that the etiology cannot be ascertained. As in so many instances in clinical practice,
815
FOOT PAIN
Table 2. AGES
0
TO
6
Probable Causes of Foot Pain by Age AGES
6
TO
12
III fitting shoes Foreign body
III fitting shoes Foreign body
Occult fracture
Accessory navicular
Osteomyelitis JRA (if other joints involved) Rheumatic fever
Occult fracture Tarsal coalition (peroneal spastic flatfoot) Ingrown toenail Ewing's sarcoma
AGES
12
TO
19
III fitting shoes Foreign body Ingrown toenail Pes cavus Hypermobile flat feet with tight tendo Achilles Ankle sprains Stress fracture Ewing's sarcoma Synovial sarcoma
the pediatrician must evaluate his clinical assessment to aid in deciding whether to refer the patient, Our approach is to follow the patient's progress until the problem has resolved or the etiology becomes apparent. The more common causes of foot pain in children are outlined in Table 1. Table 2 indicates which conditions are more common in different age groups.
Extrinsic Causes III fitting shoes contribute much to foot misery, and may commence almost as soon as the infant is fitted with his first pair of shoes. "Corrective shoes" used for the treatment of clubfoot, metatarsus varus, or rotational problems can result in areas of increased pressure, especially if the deformity is not flexible. An infant can only express discomfort by irritability and fussiness, and if the shoes are responsible, they should be removed instead of "breaking them in." If a foot with a rigid deformity is fitted with a stiff nonyielding shoe, it is likely that pressure sores will develop (Fig. 1). Generally, casting is safer for correction of foot deformities, although shoes may be used to maintain correction in a flexible foot. Bleck, in an excellent review of the problems related to the shoeing of children, noted that the last of most corrective shoes are molded in such a manner that they would fit an adducted foot, but not a straight foot. 2 A tennis shoe was found to come closest to the straight outline of the majority of children's feet. A child with a straight foot placed in a shoe with a swung-in leather last shoe was apt to complain of pain in the region of the little toe, where the shoe compressed the foot. Many shoes are of inadequate width in the forefoot, and with time, calluses and corns result. Nothing more than a change to a shoe withan adequate width across the forefoot is necessary. Often, tennis shoes fulfill this need better than styled leather shoes.
816
RICHARD
H.
GROSS
Figure 1. Full thickness pressure sore in the great toe in a child treated with straight last shoes for a rigid metatarsus adductus deformity. (Courtesy of Robert Hufft, M.D.)
Ingrown toenails surprisingly are more common during the second decade of life than any other time. s The entity receives much less attention in the literature than it deserves and it is certainly worthwhile to be aware of simple preventive measures. The pediatrician can spare his patients a great deal of aggravation by informing them to square off the nail when trimming, rather than rounding the edges (Fig. 2). In~ growth is enhanced when tight fitting shoes compress the soft tissues about the nail. If ingrowth is minimal, proper toenail trimming, soaks, local hygiene, and the wearing of shoes of adequate width solve the problem. For chronically inflamed nails, removal of the ungual soft tissue fold, the nail margin and matrix, or both is usually done. However, if proper nail cutting is not done postoperatively, recurrence is usual (Fig. 3). Retained foreign bodies warrant referral to an orthopedist. Localization and removal can be frustrating and are best done under ideal operating room conditions. Foreign bodies that are not radiopaque can cause great difficulty. The author has seen a patient with a chronic draining sinus of several months duration in a foot, which was believed
Normal Nail Groove
Nail
Hypertrophied Soft Tissue
c Figure 2. A, A cross section of the distal phalanx of the great toe, showing the relationship of the nail with a normal nail groove on the left and an inflamed soft tissue fold which overlaps the nail on the right. B, When the nails are trimmed by rounding off the edges, the hypertrophied and inflamed soft tissue fold can overlap the nail, and ingrowth at the distal margin will occur. C, The correct way to trim the nail is to leave the edges squared to ensure that the trimmed edge of the nail, even if incurved, will protrude distally past the soft tissue fold and ingrowth will not occur.
T FOOT PAIN
817
Figure 3. Chronically inflamed ingrown toenails after repeated unsuccessful minor surgical procedures are deformed and hypertrophied. Ingrowth and inflammation of the soft tissue folds are still present. Total excision of the nail, the nail matrix, and the tuft of the distal phalanx was necessary.
possibly to be fungal in origin after surgical exploration did not reveal a foreign body. The sinus promptly healed when a 3 cm portion of a candied apple stick spontaneously extruded from the sinus, having not been discovered at the time of previous surgery. Structural Causes Most flexible flat feet are not painful, although there is some evidence that hypermobile flat feet associated with tight heel cords can be symptomatic in adolescence. 6 This accounts for only a small percentage of patients with flat feet. If this condition is suspected, orthopedic consultation is warranted. A bony bridge between two of the bones in the mid foot or hind foot, which is defined as "tarsal coalition," can be manifest by spasm of the peroneal muscles and a rigid spastic foot that is painful on attempted motion (Fig. 4). Although oblique radiographs often demonstrate this condition, sometimes only tomography will reveal the bony bridge. If detected early, excision of the bony bar is very effective, but if secondary degenerative changes have occurred, surgery is less effective.3 If the spasm involves the posterior tibial tendon on the medial side of the foot, an accessory navicular (often called a pre-hallus) is usually found (Fig. 5A). A prominence overlying the accessory bone, often reddened from shoe pressure, is noted, and may resemble an "extramedial malleolus" (Fig. 5B). The accessory navicular is found in perhaps 10 per cent of all feet, but the majority are asymptomatic and will fuse to the body of the navicular by the time of skeletal maturity. Although this condition is classically felt to accompany a flat foot, this has usually not been the case in our experience. Again, in symptomatic feet, simple surgical excision accompanied by rerouting the tendon is very effective. Although cavus (high arch) feet have not received the widespread notorietyof the flat foot, they are generally more symptomatic and a much
818
RICHARD
H.
GROSS
Figure 4. A. Prominence of peroneal tendons at the level at the lateral malleolus is characteristic of a peroneal spastic flat foot. Attempts to invert the foot, placing these tendons on stretch, will be painful for the patient. B, Oblique view demonstrating incomplete bony bridge between the navicular and the calcaneus. At the time of surgery, there was a complete bar with cartilage in the apparent defect on the x-ray. The bony-cartilaginous bar was firm, allowing no motion. Symptomatic relief followed excision of the bar. (Courtesy of Jack Spencer, M.D.)
more significant problem for the patient (Fig. 6). Neurological disorders, especially spinal dysraphism, Charcot-Marie-Tooth disease, or Friedreich's ataxia, should be suspected, especially when the cavus is progressive or asymmetric. 9 With localized areas of weight bearing (as opposed to the flat foot, where the load is shared by a large portion of the plantar surface), calluses under the metatarsal heads are common as are claw toes. Shoe correction with metatarsal pads or bars may assist in relief, but surgical intervention usually is eventually required. The orthopedic management of these feet can be difficult, but it is probably well to involve the orthopedist relatively early in the care of cavus feet. Again, it is difficult to overemphasize the relationship of cavus feet to neurological disorders. The osteochondroses (avascular necrosis) of the bones of the foot have been felt to be a source of pain. Often the osteochondritic process is an incidental radiographic finding and is not symptomatic. The navi-
FOOT PAIN
819
Figure 5. A, Accessory navicular (arrow) is not always an obvious finding. B, Clinical appearance.
Figure 6. Clinical appearance of cavus feet. Notice the clawing of the toes and the posture of the foot, with weight bearing entirely on the heel pad and the metatarsal heads.
820
RICHARD
H.
GROSS
Figure 7. Dense tarsal navicular (right) compared with normal navicular (left) indicative of osteochondrosis of the navicular- Kohler's disease.
culat is most often involved (Fig. 7). A similar process has been described on the calcaneus, but radiographs of asymptomatic feet are indistinguishable from those felt to represent an osteochondrosis. Arch supports may be used, but informing parents of the benign natural history is most useful, and usually minimal additional treatment is required. l l A shoe elevation or a "heel cup" is often helpful in relieving symptoms in the os calcis. An exception to this general rule is Freiberg's infraction, an osteochondrosis of the second metatarsal head which can result in long-term disability. This condition does not affect children under the age of 12. There is no effective way at present of preventing deformity in this entity.
Inflammatory Causes Septic arthritis rarely involves the ankle or foot as a primary focus, except with direct contamination with a foreign body. Osteomyelitis, however, can involve the foot, especially the os calcis and talus. This condition usually presents with fever and inability to walk, with localized swelling in the hind foot. Involvement of the foot alone in systemic conditions is unusual, and this fact can be helpful in differentiating the condition from juvenile rheumatoid arthritis or acute rheumatic fever. It is also unlikely that an unilateral inflammatory process is
821
FOOT PAIN
related to a systemic cause, but bilateral involvement should mandate a careful systemic workup. Bone scanning is often helpful prior to radiographic changes of osteomyelitis. Bone aspiration or blood cultures are necessary to establish the offending organism. Present management of this entity would indicate four weeks of appropriate intravenousantibiotic therapy if treatment is undertaken. Brodie's abscess is an abortive subacute form of osteomyelitis commonly involving the distal tibia and possibly involving the small bones of the foot (Fig. 8). Adolescent males are particularly susceptible and sustain an incidence 5 times greater than the general population.5 The sclerotic bony wall of these lesions inhibits the flow of systemic antibiotics and surgical excision is indicated. Traumatic Causes With the presence of the distal tibial epiphysis in the growing child, and the relative weakness of this structure compared with bone and ligaments, the growth plate is generally first to fail with stress. It is well to remember this when evaluating what might appear to be an ankle
Figure 8.
Figure 9.
Figure 8. Brodie's abscess of the distal tibia in an adolescent male. Notice that the density of the bone is increased surrounding the radiolucent defect. Figure 9. A stress fracture of the base of the fifth metatarsal in a skeletally mature patient was not visible on the initial films, with the fracture line being visible only two weeks after the time of the original complaint. The bony margins of the fracture site have resorbed, accounting for the radiographic lucency at this time.
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H.
GROSS
sprain and obtain the appropriate radiographs, as ankle sprains in children are unusua1. 10 A more complete discussion of epiphyseal injuries is available elsewhere in this volume. In the adolescent, stress fractures can occur, especially when the patient undergoes a sudden increase in physical activity, such as the start of track season. The hallmark of these injuries is localized bony pain with a negative initial radiograph, which only shows changes at 10 to 14 days when fracture callus or resorption is noted. These injuries, however, are extremely rare under the age of 12 or 13, and most commonly involve the second metatarsal. A similar problem can occur at the base of the fifth metatarsal, the prominence on the lateral side of the mid foot. Occult fractures here also can sometimes be difficult to detect radiographically (Fig. 9). Symptoms of stress fractures are often subsiding by the time of positive radiographic findings, and treatment up to this point is expectant. If the diagnosis is suspected and the patient is unable to walk, casting is probably best, and certainly does no harm even if the suspicion of stress fracture is not confirmed. Achilles tendonitis is often seen in the same type of patient who is subject to stress fracture and is probably an "overuse" syndrome, resulting in small partial tears of the tendon. The condition is diagnosed by a localized tenderness in the tendon differentiated by palpation from bony tenderness in the calcaneus itself which is a different entity. Treatment of tendonitis consists of rest, immobilization, or a combination of the two. Local injections of steroid into the tendon should never be done, as they weaken the tendon while improving symptoms, and increase the chances of subsequent complete rupture. Tumors - Tumors of the feet are rare in children, although they occur with enough frequency so that one cannot be comfortable in excluding them from a differential diagnosis. The benign osteoid osteoma can affect the small bones of the foot, causing a dull pain, especially at night. Surgical excision is curative. In general, it is not particularly important for the pediatrician to be familiar with the unusual benign bone tumors in this area, but it is important to be aware that Ewing's sarcoma and synovial sarcoma, both tumors with a poor prognosis, often involve the foot.1 Ewing's tumor can involve a somewhat younger age group, whereas synovial sarcoma has a predilection for males later in the second decade. The important aspect in diagnosis is not to ignore persistent pain or swelling. Summary A general approach to the child with foot pain has been described. In that the pediatrician is so often the recipient of parent's questions about children's shoes, it is well for him to be aware of problems relating to poorly fitting shoes, probably the most common so~rce of complaints of foot pain in children. With a systematic approach, the pediatrician is very capable of managing the majority of such complaints.
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REFERENCES 1. Aegerter, E., and Kirkpatrick, J.:, Orthopaedic Disease. Philadelphia, W. B. Saunders Co., 1975. 2. Bleck, E.: The shoeing of children-Sham or science? Dev. Med. Child. Neurol., 13:188, 1971. 3. Cowell, H. R: Diagnosis and management of peroneal spastic flatfoot. AAOS Inst. Course Lectures, Vol. 24. St. Louis, C. V. Mosby Co., 1975, p. 94. 4. Devas, M. D.: Stress fractures in children. J. Bone Joint Surg., 45B:528, 1964. 5. Giannestras, N.: Foot Disorders Medical and Surgical Management. Philadelphia, Lea & Febiger, 1973. 6. Harris, R I., and Beath, T.: Hypermobile flat foot with short tendo Achilles. J. Bone Joint Surg., 30A:116, 1948. 7. Inman, V.: DuVries' Surgery of the Foot. St. Louis, C. V. Mosby Co., 1973. 8. James, C. C. M., and Lassman, L. P.: Spinal dysraphism: The diagnosis and treatment of progressive lesions in spina bifida occulta. J. Bone Joint Surg., 44B:828, 1962. 9.' Lloyd-Davies, R W., and Brill, G. C.: The etiology and out-patient management of ingrowing toe nails. Brit. J. Surg., 50:292, 1963. 10. Salter, R B.: Injuries of the ankle in children. Orthop. Clin. North Am., 5:147,1974. 11. Tachdjian, M. 0.: Pediatric Orthopaedics. Philadelphia, W. B. Saunders Co., 1972. Department of Orthopaedic Surgery University of Oklahoma Health Sciences Center Box 26901 Oklahoma City, Oklahoma 73190
