Australas Radio1 1992; 36: 131-134
Midshaft Tibial Stress Fractures in Children (Report of Four Cases) K.KOZLOWSKI,M.D.,M. AZOUZ, M.D.,I.R. BARRETT,F.R.A.C.S. D. HOFF, M.D. AND J.S. SCOUGALL, M.D. Departments of Radiology and Orthopaedic Surgery Royal Alexandra Hospital for Children, Sydney, Australia and Department of Radiology The Montreal Children's Hospital, Montreal, Canada.
INTRODUCTION Four children with mid-tibial stress fractures are reported. All the patients showed diagnostic changes on plain X-rays. The suggestion of osteoid osteoma on nuclear scan examination in one patient, and the diagnosis of inclusion dermoid, foreign body granuloma or osteoid osteoma in another patient, led to unnecessary bone biopsies being performed. In children, with typical X-ray appearances of mid-tibial stress fracture, further imaging examinations are not only unnecessary but may even be misleading. Mid-shaft tibia stress fractures in childhood are uncommon and often misdiagnosed. The purpose of this paper is to report four children with this entity and discuss the role of nuclear scan, CT and MR in the diagnosis, which is usually easily recognised on plain X-rays. MATERIAL Four children, three boys and a girl aged between 8 and 13 years are presented. The clinical and radiographic data are summarised in Table 1 and Figures 1-4. DISCUSSION Tibial stress fractures in adults are well recognised (1-4). Morris and Blickenstaff (5) recognise six zones of the tibia which may develop transverse or longitudinal fatigue fractures. These are: medial plateau, upper shaft, mid-shaft, distal shaft ('junction of the middle and distal thirds), and the distal Key words: Stress fracture Tibia Childhood
Address for cnrrespnndenc:
Dr.K. Kozlowski Royal Alexandra Hospital for Children Camperdown 2050 NSW Australia
Australasian Radiology, Vol. 36. No. 2, May. 1992
TABLE 1
Clinical and Radiographic data of the patients with mid-tibd stress Iraetrures NAME-SEX History
AGE
Clinical findings X-Ray Remarks Examination (Plain X-Rays)
ML-F 8 y.0.
Swelling of the midshaft of the 1. tibia for 4 weeks
HA-M 9 y.0.
Born with a short r.ley! and r. fibular hypoplasia. 16.3.88 leg lengthening Stress fracture procedure -right tibial osteotomy. 21.11.90stress fracture. Pain in the r.tibia for Hard, bone Nuclear scan: low grade 1 vear after exercise consistexv swelling Stress fracture wriosteal reaction in the oiduring karate. midshaft of both tibiae. in the mid:shaft of Most likely stress reaction. Swelling in the mid- the r.tibia shaft of the r.tibia Suggestion of stress fracture or osteoid ostmrna in the ttibia Biopsy: increased osteoclastic/ost&lastic activity. No osteoid osteorna nidus. No inflammatory changes. Appearances consistent with X-ray diagnosis of old stress fracture. Stress fracture CT - unusual appe;uances in Swelling on the Swelling and anterior l.leg tenderness in the the r.tibial shaft. Diagnosis: enlarging over the midshaft of the inclusion demoid, foreign last 10 months. Ltibia. body granuloma, osteoid Active in sport, osteoma. Nuclear scan: especially basketball stress fracture of the I.tibia Stress reaction in the ttibia
GG-M 11 v.0.
MJ-M 13 y.0.
Hard swelling of Stress frwture Bone scan (of the Lleg only) the anterior mid-Tech + Gallium -. portion of the 1.tibia Because of delayed healing bone biopsy perfamed 4 years after initial diagnosis. Histology: non specific. Healine " of healed fracture.
tibia (4-6cm above the tip of the medial malleolus). A sixth rare longitudinal type involves a major part of the bone. The only common tibial stress fracture in children involves the proximal tibia (6) followed by the distal tibia. In a series of 16 cases of stress fracture in children there were 10 in the tibia 7 in the upper shaft and 3 in the distal shaft (7). Other stress fractures of the tibia in childhood are rare. The mid-shaft tibial stress fracture is a common disorder of ballet dancers (8-10). It also occurs in adult and adolescent athletes and is seen sporadically in soldiers, jugglers and runners.
-
Surprisingly there are only a few isolated reports of this injury in childhood (1 I). The clinical history of mid-shaft tibial stress fractures is that of increasing pain during physical exercise. Later localised tenderness and swelling may be present. No radiological abnormality is seen initially. Cortical thickening (10) and subperiosteal new bone formation ( 1 1) are Submitted for publication on: 17th May, 1991 Resubmitted for publication on: 17th September, 1991 Accepted for publication on: 24th September. 1991
131
K. KOZLOWSKI et a1
FIGURE 1 - Mid-tibid s u e s tiacturn. Girl (8). Almond shaped sclerotic area confluent with anterior tibial cortex with linear. horizontal radio-lucency (arrow) representing stress fracture.
early radiographic findings. Usually only the anterior side of the cortex is affected. A fracture line may appear weeks or months later depending on physical activity. Case 2 is interesting in that the fracture followed a Wagner leg lengthening procedure. Overuse associated with fibular hypoplasia was considered the precipitating factor (Figures 2A and B). It is our impression that the stress reaction stage is encountered more often than the fracture line stage. Therefore children who have a clinical history suspicious of tibial stress fracture with normal X-ray findings, or who show equivocal or minimal changes in the mid-shaft of the tibia suggestive of stress reaction, should initially have a comparative view of the contralateral leg performed. This will help to evaluate minimal changes (Figures 4 A and B). Before proceeding to other expensive and time consuming examinations the child should be rested and, if the pain decreases, a follow-up X-ray examination should be performed in 14-21 days. This clin132
FIGURE 2A - and B. Mid-tibid stress fracture. Boy (9). Shortening of the right leg with fibular hypoplasia. (A), Good bony union after leg lengthening operation. (B), Stress fracture (anOWed).
ico-radiographic test will confirm a stress reaction or stress fracture and exclude malignant bone tumour, histiocytosis X or osteomyelitis which may in rare instances present with similar symptoms and signs. In a situation requiring a prompt diagnosis a nuclear scan can be performed. Isotope scanning is an examination of extreme sensitivity but little specificity. If the increased uptake is limited to the mid-shaft of both tibiae, with no other bone being affected, then the diagnosis is stress reaction or stress fracture until proved otherwise (Figure 4C). Symmetrical mid-tibia1 uptake virtually excludes diagnoses such as osteomyelitis or tumour. Isotope scanning was performed once in Cases 1 and 3 and twice in Case 4. Bilateral symmetrical uptake, limited to the mid-shaft of the tibia, should leave no doubt about the diagnosis. The possibility of osteoid osteoma suggested in Case 3 was followed by a biopsy. Biopsy was also performed in Case 1 because of slow
HGURE 2B
healing of the stress fracture. This is a potentially hazardous procedure which may be followed by infection or secondary fracture. The histology of stress fracture itself is uncharacteristic and may even be misleading.
A CT scan may rarely show a fracture line which is not seen on plain radiography (12-14). Usually in the stress stage it shows increased bone marrow density, endosteal and periosteal new bone formation and soft tissue oedema. These changes will be more marked in the stress fracture stage. The CT examination report in Case 4 was misleading as it suggested alternative diagnoses (Figure 4D). This led to an unnecessary biopsy being performed.
MR examination like nuclear scan is extremely sensitive but non-specific. It shows a long segment of low signal replacement of bone marrow in the region of the fracture on T1 weighted images. These appearances, if bilateral, may be helpful in the diagnosis of unclear cases (15). Australusion Radiology. Val. 36. No. 2 , Mu?. 1992
MIDSHAFT TIBIAL STRESS FRACTURES IN CHILDREN
FIGURE 3 - Mid-tibia1 stress fracture. Boy ( 11). Sclerosis of the mid-shaft of the ripht tibia kteriorly with a horizontal fracture line in its lower part (mowed). Nuclear scan raised the possibility of osteoid osteoma. This was followed by open biopsy.
FIGURE 4c Ausrralasian Radiology. Vol.36, No. 2. Moy. 1992
FIGURE 4A-D - Mid-tibial s m s fracture. Boy (13). (A & B), Stress fracture in the left tibia (armwed) and stress reaction in the right tibia. (C), Nuclear scan shows characteristic features of stress fracture and stress reaction. There is bilateral, symmetrical increased radionuclide accumulation in the mid-shaft of both the tibiae, more marked on the left. The focal, intense uptake in the anterior cortex represents a stress f r a c ~ r e(armwed). (D). scan demonstrates cort~cdsclerosis at the antero-lateral a s m t of the tibia1 mid-shaft with a round radiolucent area which contained a large sclerotic nidus. This was repotted as inclusion dennoid, foreign body granuloma or osteoid osteoma. No fracture l i e was shown on CT examination. ~~~
~~
~
FIGURE 4B
~~~~~~~~~
FIGURE 4D
133
K. KOZLOWSKI et al In conclusion plain X-rays of both tibiae are diagnostic in most cases of mid-tibia1 stress fractures in children. In doubtful cases nuclear scan should be performed. CT scan and MR are required only in exceptional situations ( 16). REFERENCES Devas MB. Stress fractures of the tibia in athletes or “shin soreness”. J Bone Jt Surg. 1958 4OB: 227-239. 2. Giladi M, Ahronson 2. Stein M, Danon YL, Milgrom CH. Unusual distribution and onset of stress fractures in soldiers. Clin M o p . 1985; 192: 142-146. 3. Hallel T, Amit S, Segal D. Fatigue fractures of tibiai and femoral shaft in soldiers. Clin Orthop. 1976; 118: 3543. 1.
134
4. Orava S, Jormakka E, Hulkko A. Stress fractures in young athletes. Acta Orthop Traumat Surg. 1981; 9 8 271-274. 5. Moms MJ, Blickenstaff LD. Fatigue fractures. A clinical study. Ed Charles C Thomas Springfield USA 1967pp66-1 12. 6. Kozlowski K, Pietron K, Puk E. Fracture de contrainte du tibia chez I’enfant. Ann Radiol. 1968: 11: 679-684. 7. Orava S , Hulkko A. Stress fracture of the mid-tibia1 shaft. Acta M o p Scand. 1984; 55: 35-37. 8. Burrows HJ.Fatigue infarction of the middle of the tibia in ballet dancers. J Bone Jt Surg. 1956; 38B: 83-94. 9. Nussbaum AR, Treves ST,Micheli L. Bone stress lesions in ballet dancers: scintigraphic assessment. AJR. 1988; 150: 851-855. 10. Schneider HJ,King AY, Bronson JL, Miller EH. Stress injuries and developmental change of lower extremities in ballet dancers. Radiology. 1974; 113: 627-632.
11. Devas MB. Stress fractures in children. J Bone Jt Surg. 1963; 45B: 528-541. 12. Murcia M, Brennan RE, Edeiken J. Computed tomography of stress fracture. Skeletal Radiol. 1982: 8: 193-195. 13. Sommer K, Meuerman KOA. Computed tomography of stress fracture. J Comput Assist Tomogr. 1982; 6 109-115. 14. Yousem D, Magid D, Fishman EK, Kuhajda F, Siegelman SS. Computed tomography of stress fractures. J Comput Assist Tomogr. 1986; 1 0 92-95. 15. Lee KJ, Yao L. Stress fractures: MR imaging. Radiology 1988; 169 217-220. 16. Horev G, Koremich L, Ziv N, Grunebaum M. The enigma of stress fractures in the pediatric age: clarification or confusion through the new imaging modalities. Pediatr Radiol 1990; 20: 469471.
Australasian Radiology. Vid. 36. No. 2 . May. 1992
Midshaft Tibial Stress Fractures in Children (Report of Four Cases) K.KOZLOWSKI,M.D.,M. AZOUZ, M.D.,I.R. BARRETT,F.R.A.C.S. D. HOFF, M.D. AND J.S. SCOUGALL, M.D. Departments of Radiology and Orthopaedic Surgery Royal Alexandra Hospital for Children, Sydney, Australia and Department of Radiology The Montreal Children's Hospital, Montreal, Canada.
INTRODUCTION Four children with mid-tibial stress fractures are reported. All the patients showed diagnostic changes on plain X-rays. The suggestion of osteoid osteoma on nuclear scan examination in one patient, and the diagnosis of inclusion dermoid, foreign body granuloma or osteoid osteoma in another patient, led to unnecessary bone biopsies being performed. In children, with typical X-ray appearances of mid-tibial stress fracture, further imaging examinations are not only unnecessary but may even be misleading. Mid-shaft tibia stress fractures in childhood are uncommon and often misdiagnosed. The purpose of this paper is to report four children with this entity and discuss the role of nuclear scan, CT and MR in the diagnosis, which is usually easily recognised on plain X-rays. MATERIAL Four children, three boys and a girl aged between 8 and 13 years are presented. The clinical and radiographic data are summarised in Table 1 and Figures 1-4. DISCUSSION Tibial stress fractures in adults are well recognised (1-4). Morris and Blickenstaff (5) recognise six zones of the tibia which may develop transverse or longitudinal fatigue fractures. These are: medial plateau, upper shaft, mid-shaft, distal shaft ('junction of the middle and distal thirds), and the distal Key words: Stress fracture Tibia Childhood
Address for cnrrespnndenc:
Dr.K. Kozlowski Royal Alexandra Hospital for Children Camperdown 2050 NSW Australia
Australasian Radiology, Vol. 36. No. 2, May. 1992
TABLE 1
Clinical and Radiographic data of the patients with mid-tibd stress Iraetrures NAME-SEX History
AGE
Clinical findings X-Ray Remarks Examination (Plain X-Rays)
ML-F 8 y.0.
Swelling of the midshaft of the 1. tibia for 4 weeks
HA-M 9 y.0.
Born with a short r.ley! and r. fibular hypoplasia. 16.3.88 leg lengthening Stress fracture procedure -right tibial osteotomy. 21.11.90stress fracture. Pain in the r.tibia for Hard, bone Nuclear scan: low grade 1 vear after exercise consistexv swelling Stress fracture wriosteal reaction in the oiduring karate. midshaft of both tibiae. in the mid:shaft of Most likely stress reaction. Swelling in the mid- the r.tibia shaft of the r.tibia Suggestion of stress fracture or osteoid ostmrna in the ttibia Biopsy: increased osteoclastic/ost&lastic activity. No osteoid osteorna nidus. No inflammatory changes. Appearances consistent with X-ray diagnosis of old stress fracture. Stress fracture CT - unusual appe;uances in Swelling on the Swelling and anterior l.leg tenderness in the the r.tibial shaft. Diagnosis: enlarging over the midshaft of the inclusion demoid, foreign last 10 months. Ltibia. body granuloma, osteoid Active in sport, osteoma. Nuclear scan: especially basketball stress fracture of the I.tibia Stress reaction in the ttibia
GG-M 11 v.0.
MJ-M 13 y.0.
Hard swelling of Stress frwture Bone scan (of the Lleg only) the anterior mid-Tech + Gallium -. portion of the 1.tibia Because of delayed healing bone biopsy perfamed 4 years after initial diagnosis. Histology: non specific. Healine " of healed fracture.
tibia (4-6cm above the tip of the medial malleolus). A sixth rare longitudinal type involves a major part of the bone. The only common tibial stress fracture in children involves the proximal tibia (6) followed by the distal tibia. In a series of 16 cases of stress fracture in children there were 10 in the tibia 7 in the upper shaft and 3 in the distal shaft (7). Other stress fractures of the tibia in childhood are rare. The mid-shaft tibial stress fracture is a common disorder of ballet dancers (8-10). It also occurs in adult and adolescent athletes and is seen sporadically in soldiers, jugglers and runners.
-
Surprisingly there are only a few isolated reports of this injury in childhood (1 I). The clinical history of mid-shaft tibial stress fractures is that of increasing pain during physical exercise. Later localised tenderness and swelling may be present. No radiological abnormality is seen initially. Cortical thickening (10) and subperiosteal new bone formation ( 1 1) are Submitted for publication on: 17th May, 1991 Resubmitted for publication on: 17th September, 1991 Accepted for publication on: 24th September. 1991
131
K. KOZLOWSKI et a1
FIGURE 1 - Mid-tibid s u e s tiacturn. Girl (8). Almond shaped sclerotic area confluent with anterior tibial cortex with linear. horizontal radio-lucency (arrow) representing stress fracture.
early radiographic findings. Usually only the anterior side of the cortex is affected. A fracture line may appear weeks or months later depending on physical activity. Case 2 is interesting in that the fracture followed a Wagner leg lengthening procedure. Overuse associated with fibular hypoplasia was considered the precipitating factor (Figures 2A and B). It is our impression that the stress reaction stage is encountered more often than the fracture line stage. Therefore children who have a clinical history suspicious of tibial stress fracture with normal X-ray findings, or who show equivocal or minimal changes in the mid-shaft of the tibia suggestive of stress reaction, should initially have a comparative view of the contralateral leg performed. This will help to evaluate minimal changes (Figures 4 A and B). Before proceeding to other expensive and time consuming examinations the child should be rested and, if the pain decreases, a follow-up X-ray examination should be performed in 14-21 days. This clin132
FIGURE 2A - and B. Mid-tibid stress fracture. Boy (9). Shortening of the right leg with fibular hypoplasia. (A), Good bony union after leg lengthening operation. (B), Stress fracture (anOWed).
ico-radiographic test will confirm a stress reaction or stress fracture and exclude malignant bone tumour, histiocytosis X or osteomyelitis which may in rare instances present with similar symptoms and signs. In a situation requiring a prompt diagnosis a nuclear scan can be performed. Isotope scanning is an examination of extreme sensitivity but little specificity. If the increased uptake is limited to the mid-shaft of both tibiae, with no other bone being affected, then the diagnosis is stress reaction or stress fracture until proved otherwise (Figure 4C). Symmetrical mid-tibia1 uptake virtually excludes diagnoses such as osteomyelitis or tumour. Isotope scanning was performed once in Cases 1 and 3 and twice in Case 4. Bilateral symmetrical uptake, limited to the mid-shaft of the tibia, should leave no doubt about the diagnosis. The possibility of osteoid osteoma suggested in Case 3 was followed by a biopsy. Biopsy was also performed in Case 1 because of slow
HGURE 2B
healing of the stress fracture. This is a potentially hazardous procedure which may be followed by infection or secondary fracture. The histology of stress fracture itself is uncharacteristic and may even be misleading.
A CT scan may rarely show a fracture line which is not seen on plain radiography (12-14). Usually in the stress stage it shows increased bone marrow density, endosteal and periosteal new bone formation and soft tissue oedema. These changes will be more marked in the stress fracture stage. The CT examination report in Case 4 was misleading as it suggested alternative diagnoses (Figure 4D). This led to an unnecessary biopsy being performed.
MR examination like nuclear scan is extremely sensitive but non-specific. It shows a long segment of low signal replacement of bone marrow in the region of the fracture on T1 weighted images. These appearances, if bilateral, may be helpful in the diagnosis of unclear cases (15). Australusion Radiology. Val. 36. No. 2 , Mu?. 1992
MIDSHAFT TIBIAL STRESS FRACTURES IN CHILDREN
FIGURE 3 - Mid-tibia1 stress fracture. Boy ( 11). Sclerosis of the mid-shaft of the ripht tibia kteriorly with a horizontal fracture line in its lower part (mowed). Nuclear scan raised the possibility of osteoid osteoma. This was followed by open biopsy.
FIGURE 4c Ausrralasian Radiology. Vol.36, No. 2. Moy. 1992
FIGURE 4A-D - Mid-tibial s m s fracture. Boy (13). (A & B), Stress fracture in the left tibia (armwed) and stress reaction in the right tibia. (C), Nuclear scan shows characteristic features of stress fracture and stress reaction. There is bilateral, symmetrical increased radionuclide accumulation in the mid-shaft of both the tibiae, more marked on the left. The focal, intense uptake in the anterior cortex represents a stress f r a c ~ r e(armwed). (D). scan demonstrates cort~cdsclerosis at the antero-lateral a s m t of the tibia1 mid-shaft with a round radiolucent area which contained a large sclerotic nidus. This was repotted as inclusion dennoid, foreign body granuloma or osteoid osteoma. No fracture l i e was shown on CT examination. ~~~
~~
~
FIGURE 4B
~~~~~~~~~
FIGURE 4D
133
K. KOZLOWSKI et al In conclusion plain X-rays of both tibiae are diagnostic in most cases of mid-tibia1 stress fractures in children. In doubtful cases nuclear scan should be performed. CT scan and MR are required only in exceptional situations ( 16). REFERENCES Devas MB. Stress fractures of the tibia in athletes or “shin soreness”. J Bone Jt Surg. 1958 4OB: 227-239. 2. Giladi M, Ahronson 2. Stein M, Danon YL, Milgrom CH. Unusual distribution and onset of stress fractures in soldiers. Clin M o p . 1985; 192: 142-146. 3. Hallel T, Amit S, Segal D. Fatigue fractures of tibiai and femoral shaft in soldiers. Clin Orthop. 1976; 118: 3543. 1.
134
4. Orava S, Jormakka E, Hulkko A. Stress fractures in young athletes. Acta Orthop Traumat Surg. 1981; 9 8 271-274. 5. Moms MJ, Blickenstaff LD. Fatigue fractures. A clinical study. Ed Charles C Thomas Springfield USA 1967pp66-1 12. 6. Kozlowski K, Pietron K, Puk E. Fracture de contrainte du tibia chez I’enfant. Ann Radiol. 1968: 11: 679-684. 7. Orava S , Hulkko A. Stress fracture of the mid-tibia1 shaft. Acta M o p Scand. 1984; 55: 35-37. 8. Burrows HJ.Fatigue infarction of the middle of the tibia in ballet dancers. J Bone Jt Surg. 1956; 38B: 83-94. 9. Nussbaum AR, Treves ST,Micheli L. Bone stress lesions in ballet dancers: scintigraphic assessment. AJR. 1988; 150: 851-855. 10. Schneider HJ,King AY, Bronson JL, Miller EH. Stress injuries and developmental change of lower extremities in ballet dancers. Radiology. 1974; 113: 627-632.
11. Devas MB. Stress fractures in children. J Bone Jt Surg. 1963; 45B: 528-541. 12. Murcia M, Brennan RE, Edeiken J. Computed tomography of stress fracture. Skeletal Radiol. 1982: 8: 193-195. 13. Sommer K, Meuerman KOA. Computed tomography of stress fracture. J Comput Assist Tomogr. 1982; 6 109-115. 14. Yousem D, Magid D, Fishman EK, Kuhajda F, Siegelman SS. Computed tomography of stress fractures. J Comput Assist Tomogr. 1986; 1 0 92-95. 15. Lee KJ, Yao L. Stress fractures: MR imaging. Radiology 1988; 169 217-220. 16. Horev G, Koremich L, Ziv N, Grunebaum M. The enigma of stress fractures in the pediatric age: clarification or confusion through the new imaging modalities. Pediatr Radiol 1990; 20: 469471.
Australasian Radiology. Vid. 36. No. 2 . May. 1992
