- Email: [email protected]
The measurement of the rotational deformities with computed tomography in femoral shaft fractures of the children treated with early spica cast
European Journal of Radiology 47 (2003) 38 /42 www.elsevier.com/locate/ejrad
The measurement of the rotational deformities with computed tomography in femoral shaft fractures of the children treated with early spica cast Sema Bulut a,*, Okay Bulut b, Fikret Tas¸ a, Hulusi Eg˘ilmez a a b
Faculty of Medicine, Department of Radiology, Cumhuriyet University, Sivas 58140, Turkey Faculty of Medicine, Department of Orthopedics, Cumhuriyet University, Sivas 58140, Turkey Received 30 April 2002; received in revised form 12 July 2002; accepted 16 July 2002
Abstract Twenty-eight children with femoral shaft fractures, treated with early spica cast, were evaluated with computed tomography (CT), for their femoral shaft rotational deformities. The femoral torsion angles were measured on both sides. If the torsion angle of the fractured side was more than the other side, it was considered as an internal rotational deformity and if it was less, it was considered as an external rotational deformity. Internal rotational deformities were detected in nine cases and external rotational deformities were detected in 17 cases. Rotational deformity was not observed in two cases. Four cases, with a rotational deformity more than 108, were corrected with a gypsotomy through the level of the fracture. We concluded that a rotational deformity, which is an important complication in conservative treatment of the femoral shaft fractures in children, can be determined exactly with CT and corrections on the spica cast can be made with a gypsotomy. # 2002 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Femoral shaft fracture; Child; Rotational deformity; Computed tomography; Early spica cast
1. Introduction Torsion angle of the femoral neck is the angle between the plane of the femoral neck (cervical plane) and the plane of the femoral condyles (condylar plane). If the torsion angle of the femoral neck is greater than 08, this condition is called ‘‘the positive torsion angle of the femoral neck’’ (positive TAFN) or ‘‘anteversion’’. If it is smaller than 08, this condition is called ‘‘the negative torsion angle of the femoral neck’’ (negative TAFN) or ‘‘retroversion’’. In normal newborn, the torsion angle of the femoral neck (TAFN) is between /348 and /408. This angle becomes smaller after the newborn period and in adults it is between /108 and /158 [1,2].
* Corresponding author. Tel.: /90-346-2191280; fax: /90-3462191284. E-mail address: [email protected] (S. Bulut).
The femoral neck anteversion angle is an important factor for hip stability and normal walking. Sometimes, abnormal femoral neck anteversion angle can be associated with many clinical problems. In the early childhood, harmless deformities, and in the adults, osteoarthritis of the hip and the knee can be seen. In most of the cases, it is associated with minor functional problems in childhood during growth. The child must be examined carefully and an accurate diagnosis must be established. If there is a severe functional disability, derotational osteotomy should be done in the late childhood [3]. In the childhood period, femoral distortion is seen in various congenital diseases such as congenital hip dislocation. This deformity can also be seen in the fractures of the femur. The femoral shaft fractures of the children are usually treated conservatively, except some special indications. The management of the femoral fractures in children depends on various factors such as the age, the type of the fracture, existence of additional trauma and the preference of the clinician. The desired
0720-048X/02/$ - see front matter # 2002 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 7 2 0 - 0 4 8 X ( 0 2 ) 0 0 2 5 6 - 5
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
aim is to achieve the least complication and the least deformity [4]. In children, between 3 and 10 years, treatment of femoral fractures is controversial. Immediate or early spica casting, traction followed by application of a cast brace or spica cast, or surgical treatment procedures (external fixations, intramedullar nailing) can be applied. In the literature, there are numerous reports of satisfactory results by closed reduction and early cast immobilization. Best results with early or immediate spica casting method seem to be obtained in infants and in young children [5]. If the anteversion angle of the femur is more than 108, this has been the criterion of significant deformity. Malkawi et al. [6] found that two-thirds of the patient, among 31 children with femoral fractures, had asymptomatic rotational deformities below 108. In another study, one-third of the children with femoral fractures, treated with conservative therapy, had significant rotational deformities between 108 and 308 [7]. Newton and Mubarak [8] analyzed the financial aspects of femoral shaft fractures’ treatment in 58 children and adolescents, and determined that the total charges were lowest for those treated with early spica casting. Certainly, cost is a major factor for this conservative treatment. The deformities on frontal and sagittal plane (angular deformities) can be determined easily with conventional roentgenograms, but the deformities on transverse plane cannot be determined easily. The deformities on transverse plane (rotational deformities) can be determined easily with computed tomography (CT) through the cross-sectional imaging [9 /11]. In this study, we presented a new method called ‘‘the early spica cast supported with CT’’ in the treatment of the femoral shaft fractures of the children between 3 and 10 years. After the early application of spica cast, rotational deformities were calculated by means of the measurement of femoral anteversion with CT. The fractures, with a rotational deformity greater than 108, were corrected with a gypsotomy through the level of the fracture and the rotational correction was achieved on the femur shaft before the callus formation.
39
on the same day. The spica cast was applied between 2 and 6 days after the trauma and the cast was incorporated to a supracondylar Kirschner wire. During the measurement of the angle of the femoral torsion with CT, sedation was not required in any of the cases. Toshiba TCT-60 AX and Picker PQS model machines were used. Scanogram was performed before the CT scans (Fig. 1). As the CT scanning protocol, we used 2 s for the scan time, 125 mA, 120 kV, 1.25 spiral pitch and we did not use X-ray filter. After the scanogram, 3 mm thickness, axial cross-sections were made from both proximal femoral heads, trochanter minors and distally at the level of intercondylar notch (Fig. 2). The transcondylar axis was traced on the cross-sections of the femoral condyles. When the femoral head and neck were observed in the same cross-section, the head and neck axis was drawn. When the femoral head and neck could not be observed on the same cross-section, femoral head and neck cross-sections were taken individually and these two cross-sections were superposed (Fig. 3), and then the head and neck axis was drawn [12,13]. The transcondylar axis was superposed on the femoral head and neck axis, and then the angle of femoral torsion was directly measured (Fig. 4). The measurement was made on both femurs. The differences of the femoral torsion angle between the fractured and normal femurs were calculated as a rotational deformity. When the torsion angle of the fractured side (TAFN-f) is more than the normal side, it was considered as an internal rotational deformity. If the torsion angle of the fractured side is less than normal side (TAFN-n) it was considered as an external deformity. With the spica cast application, the fractures of the children, whose rotational deformities were greater than 108, were corrected with a gypsotomy through the level of the fracture. Also, the rotational corrections were
2. Materials and method Twenty-eight children with femoral shaft fracture were admitted to the Department of Orthopedics and Traumatology Clinics of the Cumhuriyet University Medical Faculty Hospital. On the first day of the fracture, supracondylar skeletal traction was performed with Kirschner wire. Traction and reduction were made as biplane (frontal and sagittal) with X-ray control. After closed reduction and early spica cast application, the angle of the femoral torsion was measured with CT
Fig. 1. Scanogram. There was a complete fracture on the shaft of the left femur. There is a Kirschner wire on the distal metaphysis of the left femur.
40
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
Fig. 3. Superposed image of the femoral head and neck.
3. Results
Fig. 2. Axial CT images of the femoral head (a), femoral neck (b), femoral condyles at the level of intercondylar notch (c).
achieved on the femur shafts before the callus formation. We did not use CT controls, not to give the children more radiation. After this treatment, we evaluated them clinically for 1 year.
Thirteen of the patients were girls and 15 were boys. The ages of the children were between 3 and 10 (mean 5.8) years. Right femoral shaft fracture was determined in 12 cases and left femoral shaft fracture was determined in 16 cases. Early spica cast was performed between 2 and 6 (mean 4.6) days. The measurement of the femoral head and neck axis was obtained in 12 cases through a single cross-section and in 16 cases measurements were performed by the superposition method. Rotational deformity was not observed in two cases. Internal rotational deformity was seen in nine cases and external rotational deformity was seen in 17 cases. In the cases with external rotational deformity, the angles were between 18 and 148 (mean 6.418) and in the cases with internal rotational deformity, the angles were between 28 and 238 (mean 7.448). Only four patients demonstrated rotational deformity greater than 108 and two of them were external deformities and the other two were internal deformities (Table 1). Four cases, with a rotational deformity more than 108, were corrected with a gypsotomy through the level of the fracture. After early spica cast practice, the patients were discharged from the hospital. After 1 week, their radiographic and clinical controls were made and in three patients the deformities that were seen in frontal and sagittal planes were corrected with gypsotomy. Conservative treatment with spica cast was continued between 6 and 10 (mean 8) weeks. All the patients were controlled clinically during 1 year and we did not see any rotational problem.
4. Discussion Various radiological methods such as axial, biplane and fluoroscopic methods had been used for the measurement of TAFN before CT. The rate of the error
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
41
Fig. 4. Schematic drawing. (a) Scanogram; (b) axial image of the femoral head (section A), femoral neck (section B), femoral condyles (section C); (c) axis of the femoral head and neck (superimposed image section A/B), transcondylar axis (section C) and measurement of TAFN.
Table 1 TAFN for normal (TAFN-n) and fracture (TAFN-f) femurs and their rotational deformity degrees (external or internal) Case TAFN-n (8) TAFN-f (8) Rotational number deformity (8)
Gypsotomy
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
/ / / / / / / / / / / / / / / / / / / / / / / / / / / /
18 17 22 17 16 6 5 18 16 25 15 7 27 20 /4 19 21 16 24 11 20 21 18 17 30 23 19 16
9 4 22 40 8 8 /3 13 8 25 17 /7 22 19 0 12 24 12 20 29 14 26 16 11 27 29 13 20
9 external rotation 13 external rotation 0 23 internal rotation 8 external rotation 2 internal rotation 8 external rotation 5 external rotation 8 external rotation 0 2 internal rotation 14 external rotation 5 external rotation 1 external rotation 4 internal rotation 7 external rotation 3 internal rotation 4 external rotation 4 external rotation 18 internal rotation 6 external rotation 5 internal rotation 2 external rotation 6 external rotation 3 external rotation 6 internal rotation 6 external rotation 4 internal rotation
with these methods was between /58 and /88. Recently, it was reported that CT was a valuable method for the measurement of TAFN [1,9,10,14/16]. Femoral anteversion is generally defined as torsion of the proximal femur, relative to distal femur. The femoral torsion takes place anywhere from the trochanteric region to the supracondylar region. In order to assess the rotational deformity of the fractured site, the
femoral anteversion of the unfractured site should be evaluated. For this purpose, femoral anteversion has to be measured bilaterally. Various conventional radiographic methods were formerly used for the measurement of the anteversion. Recently, the anteversion angle is measured with CT, ultrasonography (US) and magnetic resonance (MR) imaging. However, some controversy exists about the sensitivity and reliability of US. While some authors reported successful results with US in the measurement of TAFN, others believe that US is inferior to CT. However, the measurement of the femoral anteversion with CT is generally accepted as the most reliable method [17 /21]. Compared with CT as the gold standard, MR imaging is recommended for preoperative planning in pediatric patients with femoral rotation osteotomies [20]. We could not measure the femoral anteversion angle with magnetic resonance imaging because of the metallic Kirschner wire. Usually, femoral head and neck cannot be seen in the same cross-section. In these cases, we performed a superposition technique as well as techniques used by some authors [12,13]. In 16 cases, the measurements were made with the superposition technique and in 12 cases they were made without superposition. The rotational problems of the lower limb may cause early degenerative osteoarthritis and impairs the hip biomechanics. Angular deformities seen after child femoral shaft fractures have a high potential of spontaneous correction in sagittal and coronal planes. However, the spontaneous correction potential of the rotational deformities cannot be assessed. There is a statistically significant trend by pediatric orthopedist to treat older children femur fractures operatively and younger children non-operatively. The consensus treatment is age-dependent [22]. It is generally believed that the rotational deformities more than 108 have been the criteria of significant deformity, but they are generally well tolerated if the angle is less than 108 [5,6]. In another study, it is found
42
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
that significant post-traumatic femoral torsional deformities in children confirm the poor remodeling potential. Follow-up CT for 1 year showed no significant correction of the deformity [23]. Therefore, the early diagnosis and early correction of the rotational deformity of a fractured femur cannot be overemphasized. In this study, rotational deformities of fractured femurs in children were determined with CT before callus formation. Rotational deformities were detected on 26 out of 28 cases. On four cases, rotational deformities were measured over 108. In two cases, 138 and 148 external rotation deformities and in the remaining two cases, 188 and 238 internal rotation deformities were performed following early spica cast application. The deformities with an anteversion angle greater than 108 were corrected promptly with a gypsotomy through the level of the fracture. The deformities smaller than 108 were handled conservatively without any complications [6]. One year after treatment, clinical examination revealed no rotational deformity. Herein, we presented a new method called ‘‘the early spica cast supported with CT’’ in the treatment of the femoral shaft fractures of the children between 3 and 10 years. In this method, a rotational deformity, which is an important complication in conservative treatment, can be exactly determined with CT in time and an early corrective gypsotomy can be made promptly.
References [1] Mesgarzadeh M, Revesz G, Bonakdarpour A. Femoral neck torsion angle measurement by computed tomography. J Comput Assist Tomogr 1987;11(5):799 /803. [2] Murphey MD. The hip. In: Haaga JR, Lanzieri CF, Sartoris DJ, Zerhouni EA, editors. Computed tomography and magnetic resonance imaging of the whole body. St. Louis: Mosby, 1994:1448 /763. [3] Gulan G, Mativinovic D, Nemec B, Rubinic D, Ravlic-Gulan J. Femoral neck anteversion: values, development, measurement, common problems. Coll Antropol 2000;24(2):521 /7. [4] Tachdijian MO. Pediatric orthopedics. 2nd ed. Vol. 4. Philadelphia, PA: WB Saunders Company, 1990:3013 /30. [5] Kasser JR. Femoral shaft fractures. In: Rockwood Jr. CA, editor. Fractures in children, 4th ed., vol. 3. Lippincott-Raven, 1996. pp. 1195 /230.
[6] Malkawi H, Shannak A, Hadidi S. Remodeling after femoral shaft fractures in children treated by the modified Blount method. J Pediatr Orthop 1986;6:421 /9. [7] Verbeek H. Does rotational deformity following femur shaft fracture correct during growth? Reconstr Surg Travmatol 1979;17:77 /81. [8] Newton P, Mubarak S. Financial aspects of femoral shaft fractures. J Pediatr Orthop 1994;14:508 /12. [9] Starker M, Hanusek S, Rittmeister M, Thoma W. Validation of computerized tomography antetorsion angle measurement of the femur. Z Orthop Ihre Grenzgeb 1998;136(5):420 /7. [10] Hermann KL, Egund N. CT measurement of anteversion in the femoral neck: the influence of femur positioning. Acta Radiol 1997;38(4):527 /32. [11] Staheli LT, Corbett M, Wyss C, King H. Lower extremity rotational problems in children. J Bone Joint Surg A 1985;67(1):39 /46. [12] Mahboubi S, Horstmann H. Femoral torsion: CT measurement. Radiology 1986;160(3):843 /4. [13] Anda S, Terjesen T, Kvistad KA, Svenningsen S. Acetabular angles and femoral anteversion in dysplastic hips in adults: CT investigation. J Comput Assist Tomogr 1991;15(1):115 /20. [14] Lausten G, Jorgensen F, Boesen J. Measurement of anteversion of the femoral neck: ultrasound and computerised tomography compared. J Bone Joint Surg B 1989;71(2):237 /9. [15] Grutzner P, Hochstein P, Simon R, Wentzensen A. Determination of torsion angle after shaft fractures of the lower extremity */ clinical relevance and measurement techniques. Chirurg 1999;70(3):276 /84. [16] Wissing H, Buddenbrock B. Determining rotational errors of the femur by axial computerized tomography in comparison with clinical and conventional radiologic determination. Unfallchirurgie 1993;19(3):145 /7. [17] Terjesen T, Anda S. Femoral anteversion in children measured by ultrasound. Acta Orthop Scand 1987;58:403 /7. [18] Upadhyay SS, O’neil T, Burwell RG, Mouton A. A new method using ultrasound for measuring femoral anteversion (torsion): technique and reliability. Br J Radiol 1987;60:519 /23. [19] Berman L, Mitchell R, Katz D. Ultrasound assessment of femoral anteversion: a comparison with computerised tomography. J Bone Joint Surg Br 1987;69:268 /70. [20] Tomczak RJ, Guenther KP, Rieber A, Mergo P, Ros PR, Brambs HJ. MR imaging measurement of the femoral antetorsional angle as a new technique: comparison with CT in children and adults. Am J Roentgenol 1997;168(3):791 /4. [21] Rimondi E, Busacca M, Molinari M, Rollo G, Andrisano A, Mmartini A, Monti C. Study of torsion defects of the lower limbs using computerized tomography. Radiol Med (Torino) 1995;89(1 /2):22 /7. [22] Sanders JO, Browne RH, Mooney JF, Raney EM, Horn BD, Ander DJ, Hennrikus WL, Robertson WW. Treatment of femoral fractures in children by pediatric orthopedists: results of 1998 survey. J Pediatr Orthop 2001;21(4):436 /41. [23] Davids JR. Rotational deformity and remodeling after fracture of the femur in children. Clin Orthop 1994(302):27 /35.
The measurement of the rotational deformities with computed tomography in femoral shaft fractures of the children treated with early spica cast Sema Bulut a,*, Okay Bulut b, Fikret Tas¸ a, Hulusi Eg˘ilmez a a b
Faculty of Medicine, Department of Radiology, Cumhuriyet University, Sivas 58140, Turkey Faculty of Medicine, Department of Orthopedics, Cumhuriyet University, Sivas 58140, Turkey Received 30 April 2002; received in revised form 12 July 2002; accepted 16 July 2002
Abstract Twenty-eight children with femoral shaft fractures, treated with early spica cast, were evaluated with computed tomography (CT), for their femoral shaft rotational deformities. The femoral torsion angles were measured on both sides. If the torsion angle of the fractured side was more than the other side, it was considered as an internal rotational deformity and if it was less, it was considered as an external rotational deformity. Internal rotational deformities were detected in nine cases and external rotational deformities were detected in 17 cases. Rotational deformity was not observed in two cases. Four cases, with a rotational deformity more than 108, were corrected with a gypsotomy through the level of the fracture. We concluded that a rotational deformity, which is an important complication in conservative treatment of the femoral shaft fractures in children, can be determined exactly with CT and corrections on the spica cast can be made with a gypsotomy. # 2002 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Femoral shaft fracture; Child; Rotational deformity; Computed tomography; Early spica cast
1. Introduction Torsion angle of the femoral neck is the angle between the plane of the femoral neck (cervical plane) and the plane of the femoral condyles (condylar plane). If the torsion angle of the femoral neck is greater than 08, this condition is called ‘‘the positive torsion angle of the femoral neck’’ (positive TAFN) or ‘‘anteversion’’. If it is smaller than 08, this condition is called ‘‘the negative torsion angle of the femoral neck’’ (negative TAFN) or ‘‘retroversion’’. In normal newborn, the torsion angle of the femoral neck (TAFN) is between /348 and /408. This angle becomes smaller after the newborn period and in adults it is between /108 and /158 [1,2].
* Corresponding author. Tel.: /90-346-2191280; fax: /90-3462191284. E-mail address: [email protected] (S. Bulut).
The femoral neck anteversion angle is an important factor for hip stability and normal walking. Sometimes, abnormal femoral neck anteversion angle can be associated with many clinical problems. In the early childhood, harmless deformities, and in the adults, osteoarthritis of the hip and the knee can be seen. In most of the cases, it is associated with minor functional problems in childhood during growth. The child must be examined carefully and an accurate diagnosis must be established. If there is a severe functional disability, derotational osteotomy should be done in the late childhood [3]. In the childhood period, femoral distortion is seen in various congenital diseases such as congenital hip dislocation. This deformity can also be seen in the fractures of the femur. The femoral shaft fractures of the children are usually treated conservatively, except some special indications. The management of the femoral fractures in children depends on various factors such as the age, the type of the fracture, existence of additional trauma and the preference of the clinician. The desired
0720-048X/02/$ - see front matter # 2002 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 7 2 0 - 0 4 8 X ( 0 2 ) 0 0 2 5 6 - 5
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
aim is to achieve the least complication and the least deformity [4]. In children, between 3 and 10 years, treatment of femoral fractures is controversial. Immediate or early spica casting, traction followed by application of a cast brace or spica cast, or surgical treatment procedures (external fixations, intramedullar nailing) can be applied. In the literature, there are numerous reports of satisfactory results by closed reduction and early cast immobilization. Best results with early or immediate spica casting method seem to be obtained in infants and in young children [5]. If the anteversion angle of the femur is more than 108, this has been the criterion of significant deformity. Malkawi et al. [6] found that two-thirds of the patient, among 31 children with femoral fractures, had asymptomatic rotational deformities below 108. In another study, one-third of the children with femoral fractures, treated with conservative therapy, had significant rotational deformities between 108 and 308 [7]. Newton and Mubarak [8] analyzed the financial aspects of femoral shaft fractures’ treatment in 58 children and adolescents, and determined that the total charges were lowest for those treated with early spica casting. Certainly, cost is a major factor for this conservative treatment. The deformities on frontal and sagittal plane (angular deformities) can be determined easily with conventional roentgenograms, but the deformities on transverse plane cannot be determined easily. The deformities on transverse plane (rotational deformities) can be determined easily with computed tomography (CT) through the cross-sectional imaging [9 /11]. In this study, we presented a new method called ‘‘the early spica cast supported with CT’’ in the treatment of the femoral shaft fractures of the children between 3 and 10 years. After the early application of spica cast, rotational deformities were calculated by means of the measurement of femoral anteversion with CT. The fractures, with a rotational deformity greater than 108, were corrected with a gypsotomy through the level of the fracture and the rotational correction was achieved on the femur shaft before the callus formation.
39
on the same day. The spica cast was applied between 2 and 6 days after the trauma and the cast was incorporated to a supracondylar Kirschner wire. During the measurement of the angle of the femoral torsion with CT, sedation was not required in any of the cases. Toshiba TCT-60 AX and Picker PQS model machines were used. Scanogram was performed before the CT scans (Fig. 1). As the CT scanning protocol, we used 2 s for the scan time, 125 mA, 120 kV, 1.25 spiral pitch and we did not use X-ray filter. After the scanogram, 3 mm thickness, axial cross-sections were made from both proximal femoral heads, trochanter minors and distally at the level of intercondylar notch (Fig. 2). The transcondylar axis was traced on the cross-sections of the femoral condyles. When the femoral head and neck were observed in the same cross-section, the head and neck axis was drawn. When the femoral head and neck could not be observed on the same cross-section, femoral head and neck cross-sections were taken individually and these two cross-sections were superposed (Fig. 3), and then the head and neck axis was drawn [12,13]. The transcondylar axis was superposed on the femoral head and neck axis, and then the angle of femoral torsion was directly measured (Fig. 4). The measurement was made on both femurs. The differences of the femoral torsion angle between the fractured and normal femurs were calculated as a rotational deformity. When the torsion angle of the fractured side (TAFN-f) is more than the normal side, it was considered as an internal rotational deformity. If the torsion angle of the fractured side is less than normal side (TAFN-n) it was considered as an external deformity. With the spica cast application, the fractures of the children, whose rotational deformities were greater than 108, were corrected with a gypsotomy through the level of the fracture. Also, the rotational corrections were
2. Materials and method Twenty-eight children with femoral shaft fracture were admitted to the Department of Orthopedics and Traumatology Clinics of the Cumhuriyet University Medical Faculty Hospital. On the first day of the fracture, supracondylar skeletal traction was performed with Kirschner wire. Traction and reduction were made as biplane (frontal and sagittal) with X-ray control. After closed reduction and early spica cast application, the angle of the femoral torsion was measured with CT
Fig. 1. Scanogram. There was a complete fracture on the shaft of the left femur. There is a Kirschner wire on the distal metaphysis of the left femur.
40
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
Fig. 3. Superposed image of the femoral head and neck.
3. Results
Fig. 2. Axial CT images of the femoral head (a), femoral neck (b), femoral condyles at the level of intercondylar notch (c).
achieved on the femur shafts before the callus formation. We did not use CT controls, not to give the children more radiation. After this treatment, we evaluated them clinically for 1 year.
Thirteen of the patients were girls and 15 were boys. The ages of the children were between 3 and 10 (mean 5.8) years. Right femoral shaft fracture was determined in 12 cases and left femoral shaft fracture was determined in 16 cases. Early spica cast was performed between 2 and 6 (mean 4.6) days. The measurement of the femoral head and neck axis was obtained in 12 cases through a single cross-section and in 16 cases measurements were performed by the superposition method. Rotational deformity was not observed in two cases. Internal rotational deformity was seen in nine cases and external rotational deformity was seen in 17 cases. In the cases with external rotational deformity, the angles were between 18 and 148 (mean 6.418) and in the cases with internal rotational deformity, the angles were between 28 and 238 (mean 7.448). Only four patients demonstrated rotational deformity greater than 108 and two of them were external deformities and the other two were internal deformities (Table 1). Four cases, with a rotational deformity more than 108, were corrected with a gypsotomy through the level of the fracture. After early spica cast practice, the patients were discharged from the hospital. After 1 week, their radiographic and clinical controls were made and in three patients the deformities that were seen in frontal and sagittal planes were corrected with gypsotomy. Conservative treatment with spica cast was continued between 6 and 10 (mean 8) weeks. All the patients were controlled clinically during 1 year and we did not see any rotational problem.
4. Discussion Various radiological methods such as axial, biplane and fluoroscopic methods had been used for the measurement of TAFN before CT. The rate of the error
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
41
Fig. 4. Schematic drawing. (a) Scanogram; (b) axial image of the femoral head (section A), femoral neck (section B), femoral condyles (section C); (c) axis of the femoral head and neck (superimposed image section A/B), transcondylar axis (section C) and measurement of TAFN.
Table 1 TAFN for normal (TAFN-n) and fracture (TAFN-f) femurs and their rotational deformity degrees (external or internal) Case TAFN-n (8) TAFN-f (8) Rotational number deformity (8)
Gypsotomy
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
/ / / / / / / / / / / / / / / / / / / / / / / / / / / /
18 17 22 17 16 6 5 18 16 25 15 7 27 20 /4 19 21 16 24 11 20 21 18 17 30 23 19 16
9 4 22 40 8 8 /3 13 8 25 17 /7 22 19 0 12 24 12 20 29 14 26 16 11 27 29 13 20
9 external rotation 13 external rotation 0 23 internal rotation 8 external rotation 2 internal rotation 8 external rotation 5 external rotation 8 external rotation 0 2 internal rotation 14 external rotation 5 external rotation 1 external rotation 4 internal rotation 7 external rotation 3 internal rotation 4 external rotation 4 external rotation 18 internal rotation 6 external rotation 5 internal rotation 2 external rotation 6 external rotation 3 external rotation 6 internal rotation 6 external rotation 4 internal rotation
with these methods was between /58 and /88. Recently, it was reported that CT was a valuable method for the measurement of TAFN [1,9,10,14/16]. Femoral anteversion is generally defined as torsion of the proximal femur, relative to distal femur. The femoral torsion takes place anywhere from the trochanteric region to the supracondylar region. In order to assess the rotational deformity of the fractured site, the
femoral anteversion of the unfractured site should be evaluated. For this purpose, femoral anteversion has to be measured bilaterally. Various conventional radiographic methods were formerly used for the measurement of the anteversion. Recently, the anteversion angle is measured with CT, ultrasonography (US) and magnetic resonance (MR) imaging. However, some controversy exists about the sensitivity and reliability of US. While some authors reported successful results with US in the measurement of TAFN, others believe that US is inferior to CT. However, the measurement of the femoral anteversion with CT is generally accepted as the most reliable method [17 /21]. Compared with CT as the gold standard, MR imaging is recommended for preoperative planning in pediatric patients with femoral rotation osteotomies [20]. We could not measure the femoral anteversion angle with magnetic resonance imaging because of the metallic Kirschner wire. Usually, femoral head and neck cannot be seen in the same cross-section. In these cases, we performed a superposition technique as well as techniques used by some authors [12,13]. In 16 cases, the measurements were made with the superposition technique and in 12 cases they were made without superposition. The rotational problems of the lower limb may cause early degenerative osteoarthritis and impairs the hip biomechanics. Angular deformities seen after child femoral shaft fractures have a high potential of spontaneous correction in sagittal and coronal planes. However, the spontaneous correction potential of the rotational deformities cannot be assessed. There is a statistically significant trend by pediatric orthopedist to treat older children femur fractures operatively and younger children non-operatively. The consensus treatment is age-dependent [22]. It is generally believed that the rotational deformities more than 108 have been the criteria of significant deformity, but they are generally well tolerated if the angle is less than 108 [5,6]. In another study, it is found
42
S. Bulut et al. / European Journal of Radiology 47 (2003) 38 /42
that significant post-traumatic femoral torsional deformities in children confirm the poor remodeling potential. Follow-up CT for 1 year showed no significant correction of the deformity [23]. Therefore, the early diagnosis and early correction of the rotational deformity of a fractured femur cannot be overemphasized. In this study, rotational deformities of fractured femurs in children were determined with CT before callus formation. Rotational deformities were detected on 26 out of 28 cases. On four cases, rotational deformities were measured over 108. In two cases, 138 and 148 external rotation deformities and in the remaining two cases, 188 and 238 internal rotation deformities were performed following early spica cast application. The deformities with an anteversion angle greater than 108 were corrected promptly with a gypsotomy through the level of the fracture. The deformities smaller than 108 were handled conservatively without any complications [6]. One year after treatment, clinical examination revealed no rotational deformity. Herein, we presented a new method called ‘‘the early spica cast supported with CT’’ in the treatment of the femoral shaft fractures of the children between 3 and 10 years. In this method, a rotational deformity, which is an important complication in conservative treatment, can be exactly determined with CT in time and an early corrective gypsotomy can be made promptly.
References [1] Mesgarzadeh M, Revesz G, Bonakdarpour A. Femoral neck torsion angle measurement by computed tomography. J Comput Assist Tomogr 1987;11(5):799 /803. [2] Murphey MD. The hip. In: Haaga JR, Lanzieri CF, Sartoris DJ, Zerhouni EA, editors. Computed tomography and magnetic resonance imaging of the whole body. St. Louis: Mosby, 1994:1448 /763. [3] Gulan G, Mativinovic D, Nemec B, Rubinic D, Ravlic-Gulan J. Femoral neck anteversion: values, development, measurement, common problems. Coll Antropol 2000;24(2):521 /7. [4] Tachdijian MO. Pediatric orthopedics. 2nd ed. Vol. 4. Philadelphia, PA: WB Saunders Company, 1990:3013 /30. [5] Kasser JR. Femoral shaft fractures. In: Rockwood Jr. CA, editor. Fractures in children, 4th ed., vol. 3. Lippincott-Raven, 1996. pp. 1195 /230.
[6] Malkawi H, Shannak A, Hadidi S. Remodeling after femoral shaft fractures in children treated by the modified Blount method. J Pediatr Orthop 1986;6:421 /9. [7] Verbeek H. Does rotational deformity following femur shaft fracture correct during growth? Reconstr Surg Travmatol 1979;17:77 /81. [8] Newton P, Mubarak S. Financial aspects of femoral shaft fractures. J Pediatr Orthop 1994;14:508 /12. [9] Starker M, Hanusek S, Rittmeister M, Thoma W. Validation of computerized tomography antetorsion angle measurement of the femur. Z Orthop Ihre Grenzgeb 1998;136(5):420 /7. [10] Hermann KL, Egund N. CT measurement of anteversion in the femoral neck: the influence of femur positioning. Acta Radiol 1997;38(4):527 /32. [11] Staheli LT, Corbett M, Wyss C, King H. Lower extremity rotational problems in children. J Bone Joint Surg A 1985;67(1):39 /46. [12] Mahboubi S, Horstmann H. Femoral torsion: CT measurement. Radiology 1986;160(3):843 /4. [13] Anda S, Terjesen T, Kvistad KA, Svenningsen S. Acetabular angles and femoral anteversion in dysplastic hips in adults: CT investigation. J Comput Assist Tomogr 1991;15(1):115 /20. [14] Lausten G, Jorgensen F, Boesen J. Measurement of anteversion of the femoral neck: ultrasound and computerised tomography compared. J Bone Joint Surg B 1989;71(2):237 /9. [15] Grutzner P, Hochstein P, Simon R, Wentzensen A. Determination of torsion angle after shaft fractures of the lower extremity */ clinical relevance and measurement techniques. Chirurg 1999;70(3):276 /84. [16] Wissing H, Buddenbrock B. Determining rotational errors of the femur by axial computerized tomography in comparison with clinical and conventional radiologic determination. Unfallchirurgie 1993;19(3):145 /7. [17] Terjesen T, Anda S. Femoral anteversion in children measured by ultrasound. Acta Orthop Scand 1987;58:403 /7. [18] Upadhyay SS, O’neil T, Burwell RG, Mouton A. A new method using ultrasound for measuring femoral anteversion (torsion): technique and reliability. Br J Radiol 1987;60:519 /23. [19] Berman L, Mitchell R, Katz D. Ultrasound assessment of femoral anteversion: a comparison with computerised tomography. J Bone Joint Surg Br 1987;69:268 /70. [20] Tomczak RJ, Guenther KP, Rieber A, Mergo P, Ros PR, Brambs HJ. MR imaging measurement of the femoral antetorsional angle as a new technique: comparison with CT in children and adults. Am J Roentgenol 1997;168(3):791 /4. [21] Rimondi E, Busacca M, Molinari M, Rollo G, Andrisano A, Mmartini A, Monti C. Study of torsion defects of the lower limbs using computerized tomography. Radiol Med (Torino) 1995;89(1 /2):22 /7. [22] Sanders JO, Browne RH, Mooney JF, Raney EM, Horn BD, Ander DJ, Hennrikus WL, Robertson WW. Treatment of femoral fractures in children by pediatric orthopedists: results of 1998 survey. J Pediatr Orthop 2001;21(4):436 /41. [23] Davids JR. Rotational deformity and remodeling after fracture of the femur in children. Clin Orthop 1994(302):27 /35.