- Email: [email protected]
Deficient dorsalis pedis flow in severe idiopathic clubfeet: Does Ponseti casting affect the outcome?
Accepted Manuscript Title: Deficient dorsalis pedis flow in severe idiopathic clubfeet. Does Ponseti casting affect the outcome? Authors: Ismail MUNAJAT, Mehran YOYSEFI, Nik Munirah NIK MAHDI PII: DOI: Reference:
S0958-2592(16)30138-9 http://dx.doi.org/doi:10.1016/j.foot.2017.05.003 YFOOT 1480
To appear in:
The Foot
Received date: Accepted date:
17-12-2016 7-5-2017
Please cite this article as: MUNAJAT Ismail, YOYSEFI Mehran, NIK MAHDI Nik Munirah.Deficient dorsalis pedis flow in severe idiopathic clubfeet.Does Ponseti casting affect the outcome?.The Foot http://dx.doi.org/10.1016/j.foot.2017.05.003 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Title: Deficient dorsalis pedis flow in severe idiopathic clubfeet. Does Ponseti casting affect the outcome?
Authors: Ismail MUNAJAT MBBS MMed* Mehran YOYSEFI MBBS MMed* Nik Munirah NIK MAHDI MBBS MMed¥
*
Department of Orthopaedics, School of Medical Sciences, Universiti Sains Malaysia (USM),
Kubang Kerian, 16150 Kota Bharu, Kelantan, Malaysia. ¥
Department of Radiology, School of Medical Sciences, Universiti Sains Malaysia (USM),
Kubang Kerian, 16150 Kota Bharu, Kelantan, Malaysia.
Corresponding author: Ismail Munajat, Department of Orthopaedics, School of Medical Sciences, Universiti Sains Malaysia (USM), Kubang Kerian, 16150 Kota Bharu, Kelantan, MALAYSIA Email : [email protected] ; Tel : +609-7676398 ; Fax : +609-7676389
Highlights:
Pirani severity scores of 5 and more are at higher risk of getting arterial deficiency
Dorsalis pedis artery is the one affected most
Ponseti casting is able to reconstitute the arterial flow in the majority of cases, which are initially deficient
Background Congenital clubfoot or Congenital Talipes Equinovarus (CTEV) is one of the most important congenital deformities in newborn. It is not a self-limiting disease; hence progressive feet deformity among untreated patients potentially affects the quality of life. Serial Ponseti manipulation and casting has been established as the most widely accepted treatment for CTEV over several years The severity of clubfoot has been correlated with the involvement of the soft tissue [1]. However, the relationship between the severity of the clubfoot and arterial deficiency has not been far investigated. Furthermore, a remarkable percent of the patients need a surgical intervention to release the contracted soft tissues and to facilitate the correction of the equines [2]. Deficiency in a specific artery in CTEV gives a signal to the orthopaedic surgeons to protect other dominant blood vessels during surgery. Furthermore, maintaining the corrected foot in a cast has to be well fitted and compliant to the regime. Studies on the association between arterial deficiency and clubfoot severity, and studies on the effect of Ponseti treatment on the arterial deficient clubfoot are still lacking. Therefore, the present study aims to investigate the association between severity of clubfoot and arterial deficiency as well as to find the effect of Ponseti treatment on the vascular status among feet with CTEV.
Method This prospective study was conducted from April 2011 to October 2012. A total number of 18 babies (24 feet) with congenital clubfeet and Pirani score ranging between 2 to 6 fulfilled the inclusion and exclusion criteria. Inclusion criteria were infants delivered with CTEV up to oneyear-old, babies who were never treated for CTEV elsewhere and population confined within the country. Exclusion criteria were patients who received unsuccessful or incomplete casting
treatment somewhere else, patients who had surgical correction before, syndromic patients with CTEV and patients who had other complex disorders such arthrogryposis, teratologic disorder and myelomeningocele. Eighteen normal babies (36 normal feet) were selected as control from postnatal ward. The severity of congenital clubfoot was assessed using Pirani severity score. The severity scores were grouped as follows; severity score 1(Pirani score 0.5 to 1.5), severity score 2(Pirani score 2 to 2.5), severity score 3(Pirani score 3 to 3.5), severity score 4(Pirani score 4 to 4.5), severity score 5(Pirani score 5 to 5.5) and severity score 6(Pirani score 6). Both study and control groups were subjected to Color Doppler Ultrasound for dorsalis pedis and posterior tibial arteries study before starting the Ponseti treatment. A single qualified radiologist performed the Color Doppler Ultrasound examination. For this purpose, Color Doppler Ultrasound machine (SIMENS-ACUSON S2000-USA) was employed. A normal artery is defined as an artery that is detectable and has antegrade flow while deficient artery is defined as an artery which is either not detectable or detected but has retrograde flow. All feet with CTEV underwent serial Ponseti manipulation and casting as a weekly basis until full correction. Second Color Doppler Ultrasound was performed in study group upon completion of Ponseti treatment just before applying the Dennis Brown Shoes as foot abduction brace. All data collection was recorded in SPSS (versions 20).
Results From 24 CTEV feet, 7(29.1%) had vascular abnormalities [Figure 1]. In these 7 feet, all dorsalis pedis had absent arterial flow [Figure 2a], while posterior tibial arteries were detectable with a normal antegrade flow [Figure 2c]. The remaining 17 CTEV feet (70.8%) had normal antegrade arterial flow. The arterial flow of dorsalis pedis and posterior tibial arteries were normal in all cases in the control group. Statistical comparison of the vascularity between study
and control group was not achievable; however, there was a noticeable difference in proportion between study and control group. All 7 CTEV feet with arterial abnormality were in the group of severity score 5 (71.4%) and 6 (28.5%). There was no arterial deficiency noted with severity score less than 5 [Figure 3]. The arterial abnormality and the severity of the Pirani score were not directly proportional. The mean of Pirani severity score in deficient vascular CTEV was 5.3, which was higher than the mean of Pirani severity in normal vascular CTEV (4.2). Analysis of these collected data, using Non-parametric Mann-Whitney test demonstrated that babies with higher severity score were associated with more abnormal vascularity compared with lower severity score (p=0.008). There was 85.7 % (6 of 7 feet) of arterial deficient feet reconstituted the blood flow after Ponseti treatment [Figure 2b] which was statistically significant (p= 0.031) as in table I. Only 1 foot remained arterial deficient despite full deformity correction after Ponseti treatment.
Discussion Several studies have been reported about the theories of pathogenesis behind CTEV [3, 4]. They had postulated the role of primary germplasm effect on the abnormality of the talus, but they have not found vascular abnormalities in their study. The vascular theory had been presented in clubfoot, which has explained that lack of anterior tibial artery leads to medial tightness and dysplasia of talus angle [4]. Studies have suggested a 3.7% to 12% prevalence of deficient dorsalis pedis arteries in normal feet [5, 6]. The prevalence of deficient dorsalis pedis artery in limbs with idiopathic clubfoot had been reported 84% in 16 feet with the age range of 1.3 to 13.5(average 6.3 years) using angiographic study [7]. Based on the data from above studies, deficient dorsalis pedis artery can still occur in the normal population in which the percentage may vary with different races and geographical areas. However, a study
comparing the prevalence of deficient posterior tibial artery in normal and in feet with CTEV is still lacking even though it may be less common. Edelson JG and Husseini N had encountered an incidence of pulseless vascularity (6.7%) in the severe clubfoot among children less than 3-years-old compared to the normal control (3.2%) [8]. An absent or anomalous posterior tibial artery is a very uncommon finding in patients with clubfoot and deficiency of posterior tibial artery is less common than dorsalis pedis artery in patients with congenital clubfoot [9, 10]. The exact aetiology on why the posterior tibial artery is less commonly involved remains unknown. In our opinion, due to the equinus and adduction deformities, dorsalis pedis artery is at a higher risk of being stretched and compressed over the deformed tarsal bones at the dorsum part of the foot compared to the posterior tibial artery at the posterior. In our study, there was no deficiency of posterior tibial arteries detected in the CTEV group. The posterior tibial artery was found to be absent in two patients at the time of an operative release procedure for clubfoot, and its arteriographic appearance of an absent posterior tibial artery was also studied [11]. Abnormal vascularity had been described as absent or retrograde flow [12]. Color Doppler Ultrasound is a perfect tool for assessing the presence of the arterial flow as well as the direction of the flow compared with conventional ultrasound. In our study, all of the arterial insufficiencies were detected as absent flow rather than retrograde flow. One of the critical initial assessments of CTEV is to determine the severity of the deformity. Some severity scoring systems have been described which include Lehman, Dimeglio and Pirani scoring systems. Scoring system should be practically simple, possible in a clinical setting, reliable, and able to envisage suitable plan for management [13, 14]. Pirani scoring system is chosen in this study because it is simple, fast and reliable. Furthermore, it does not use any radiation to complete the scoring unlike in Lehman scoring system. Although Dimeglio scoring is complex, however, this system is also one of the best-accepted scoring system [13].
Edelson JG and Husseini N had used Lehman’s scoring and a Doppler technique for a study on the arterial pulse in clubfoot and reported that the incidence of pulselessness increased with the severity and duration of deformity [8]. Their finding was rather consistent with our study whereby increasing the severity score was associated with increased incidence of arterial deficiency despite different severity scoring system used. However, our study revealed a higher percentage of arterial deficient feet (29.1%) in younger patients (less than 1-year-old) compared to only 7% in children under 3 years of their study. They also examined the relationship between the duration of deformity and the incidence of pulselessness which was good since it has never been studied before. However, to conduct a similar study now or near future on the duration of deformity might be less feasible since anxious parents tend to bring their babies with clubfeet earlier for treatment. A late presentation of clubfoot might be difficult to recruit for study owing to increasing public awareness and education towards clubfoot. Pulsed Color-Flow Doppler was used by Katz et al, in the analysis of arterial deficiency in idiopathic clubfoot and noted that the prevalence of deficiency of dorsalis pedis artery in clubfeet requiring surgery was 54% compared those that did not (20%) [12]. In contrast with our study, Katz et al, did not use any severity score to correlate with vascular deficiency but rather assuming that decision to treat a foot surgically was indicative of more severe involvement [12]. In our opinion, severe clubfeet which show poor progression with Ponseti casting warrant proper documentation of severity score once decision to discontinue casting has been made. A vascular assessment using Color Doppler Ultrasound can then be arranged before any surgical release. Several studies were attempted to find an effective way to demonstrate the lower limbs vascular malformation. Contrast angiography is presented as a gold standard for the diagnosis of arterial abnormalities [7]. The vascular pattern has been shown very well with this method. However, it is an invasive study with high risk of arterial damage, haemorrhage, ischemia and allergic
reaction. MRA have been applied for CTEV cases successfully, but contrast MRA is as invasive as contrast angiography if used for vascular assessment in CTEV [15, 16, 17]. Noncontrast MRA is a noninvasive method, but it has limitations such as time-consuming and needs for anaesthesia for babies. Therefore, Color Doppler Ultrasound was preferably chosen because of its safety and noninvasiveness during vascular assessment particularly in babies aged less than 15 weeks old like in this study. We also thought that Color Doppler Ultrasound was easy to use and radiation free. Initial Wave Doppler Ultrasound study on arterial blood vessel could not determine the difference in prevalence of vascular abnormality between CTEV cases and normal controls [8]. Pinto et al, later investigated the role of Color Doppler Ultrasound in assessing the vascular status in CTEV and they found that Color Doppler Ultrasound has not shown a significant variation of arterial morphology and flow speed between affected foot and normal contralateral side [17]. But they have noticed that patient with a larger diameter of anterior tibial artery had a better response to treatment, and more severe vascular abnormality of CTEV may be associated with the more resistant to deformity correction [17]. Based on above study, it seems that severe vascular abnormality is more likely to be associated with severe soft tissue involvement leading to a poor response to treatment, whereas, clubfeet with less vascular and soft tissue involvement may have a better response. There were few kinds of literature previously studied on the Doppler ultrasound used in the vascular assessment of CTEV. Yildirim T et al, evaluated the changes observed in the main arteries of the foot before and after the Ponseti technique using Doppler ultrasound [18]. It was found that Ponseti method resulted in normalisation of the arterial structures in extremities with congenital talipes equinovarus [2]. This finding was consistent with our study. However, we believe our study has an additional advantage as Color Doppler Ultrasound and Pirani severity
score were used. Compared to their study, we scored the clubfoot severity and analysed it with the patency of the arterial flow. There was a study by Merrill et al, who somewhat looked into arterial abnormalities in clubfoot not in early life presentation but rather when the clubfoot had recurrence [1]. They have shown that vascular abnormalities were present in all three patients with recurrent clubfoot, suggesting these anatomic abnormalities may be predictive of response to treatment [1]. However, that study was conducted in bigger children and adults aged from 6 to 60 years, and non-contrast MRA was used for vascular assessment instead of Color Doppler Ultrasound [1]. Based on above study, there will be a risk of recurrence in 6 feet with CTEV in the current study since the first Color Doppler Ultrasound revealed an arterial deficiency. A longer follow-up is needed to evaluate the outcome of these 6 clubfeet who resume the arterial flow after Ponseti treatment particularly in evaluating the risk of recurrence. The importance of this study is that when there is an absence of anterior tibial artery found during vascular assessment with Color Doppler Ultrasound, posterior tibial artery should be well protected if a surgical release of the clubfoot is needed in the future. If both anterior and posterior tibial arteries are absent during clubfoot assessment which is unusual, it will serve as a warning of potential precarious circulation to the foot, and peroneal artery may be dominant [11]. Severe congenital clubfoot with high Pirani severity score requiring surgery may warrant preoperative vascular assessment using Color Doppler Ultrasound to detect any arterial deficiency associated with the severity of the deformity. It may be beneficial to document foot vascularity using Color Doppler Ultrasound, particularly in severe CTEV before starting Ponseti casting.
Conclusion In conclusion, arterial deficiency is found in 29.1% of CTEV feet in the current study and all affected vessels are dorsalis pedis arteries. Pirani severity scores of 5 and more are at higher risk of getting an arterial deficiency. As much as 85.7% of arterial deficient CTEV feet regain their blood flow after Ponseti treatment. We believe the dorsalis pedis artery is present since birth with normal morphology, however, the deformity of the feet compresses it and makes it less patent, particularly with more severe deformity. We also believe that correcting the deformity alleviates the compression, thus, restores the patency of the arterial blood flow. Ponseti treatment is able to correct the deformity as well as to reconstitute the arterial flow in the majority of cases which are initially deficient.
Acknowledgement This study was approved by The Research Ethics Committee (Human) on 8th May 2011. This study was not funded by any organisation.
References [1] Merrill LJ, Gurnett CA, Siegel M, Pirani S, Dobbs MB. Vascular abnormalities correlate with decreased soft tissue volumes in idiopathic clubfoot. Clinical Orthopaedics and Related Research 2011; 469: 1442-1449. [2]
Chu A, Lehman WB. Persistent clubfoot deformity following treatment by the Ponseti
method. Journal of Pediatric Orthopaedics B 2012; 21:40-46 [3] Irani RN, Sherman MS. The pathological anatomy of clubfoot. The Journal of Bone and Joint Surgery Am 1963; 45: 45-52. [4]
Hootnick D, Packard Jr D, Levinsohn E, et al. The anatomy of a congenitally short limb
with clubfoot and ectrodactyly. Teratology 1984; 29: 155-164. [5]
Sarrafian S. Functional anatomy of the foot and ankle. Anatomy of the foot and ankle,
descriptive, topographic, functional. 2nd ed. Philadelphia: JB Lippincott; 1993; 474-602. [6] Huber JF. The arterial network supplying the dorsum of the foot. The Anatomical Record 1941; 80, 373-391. [7]
Greider TD, Siff S, Gerson P, Donovan M. Arteriography in club foot. The Journal of
bone and joint surgery Am 1982; 64: 837. [8]
Edelson JG, Husseini N. The pulseless club foot. J Bone Joint Surg Br 1984; 66: 700-
702. [9] Quillin SP, Hicks ME. Absent posterior tibial artery associated with clubfoot deformity: an unusual variant. Journal of Vascular and Interventional Radiology 1994; 5: 497-9. [10] Kitziger K, Wilkins K. Absent posterior tibial artery in an infant with talipes equinovarus. J Pediatr Orthop 1991; 11: 777-8. [11] Dobbs MB, Gordon JE, Schoenecker PL. Absent Posterior Tibial Artery Associated with Idiopathic Clubfoot: A Report of Two Cases. The Journal of Bone and Joint Surgery Am 2004; 86: 599-602.
[12]
Katz DA, Albanese EL, Levinsohn EM, Katz, Hootnick DR, Packard DS, Grant WD,
Mann KA, Albanese SA. Pulsed color-flow Doppler analysis of arterial deficiency in idiopathic clubfoot. Journal of Pediatric Orthopaedics 2003; 23: 84-87. [13]
Wainwright AM, Auld T, Benson MK, Theologist TN. The classification of congenital
talipes equinovarus. Journal of Bone & Joint Surgery, British Volume 2002; 84: 1020-1024. [14]
Dyer P, Davis N. The role of the Pirani scoring system in the management of clubfoot
by the Ponseti method. The Journal of Bone and Joint Surgery Br 2006; 88: 1082-1084. [15]
Kruse L, Gurnett CA, Hootnick DR, Dobbs MB. Magnetic resonance angiography in
clubfoot and vertical talus: a feasibility study. Clinical Orthopaedics and Related Research 2009; 467: 1250-1255. [16]
Marckmann P, Skov L, Rossen K, et al. Nephrogenic systemic fibrosis: suspected
causative role of gadodiamide used for contrast-enhanced magnetic resonance imaging. Journal of the American Society of Nephrology 2006; 17: 2359-2362. [17] Pinto JA, Blumetti FC, Iha LAN, Terasaka MK, Sodré H, Ishida A. Evaluation of arterial anatomy in congenital clubfoot with color doppler ultrasound. Acta Ortopédica Brasileira 2008; 16: 270-274. [18]
Yildirim T, Bursali A, Tonbul M, Sakizlioglu SS, Camurcu Y. Does the Ponseti
technique affect the vascular development in patients with congenital talipes equinovarus? J Pediatr Orthop B 2015; 24: 6-10.
40
Abnormal flow
Normal flow
36
35
Number of feet
30
25
20 17 15
10 7 5
0 0
CTEV GROUP
CONTROL GROUP
Fig 1: Bar graph shows the proportion of feet with arterial blood flow abnormality in CTEV and control groups
b
a
LT POSTERIOR TIBIAL A
c
Fig 2: Color Doppler Ultrasound shows the deficient of blood flow in dorsalis pedis artery prior to Ponseti casting (a), the presence of blood flow in dorsalis pedis artery after completed Ponseti casting (b) and the normal blood flow in posterior tibial artery prior to Ponseti casting (c).
Normal flow
Abnormal flow
40
37.5
35
9 feet
Percentage
30 25 20.8
20 15
12.5
10
0
0
1
4 feet
3 feet
4.1
5
0
5 feet
16.7
1 foot
0
2
8.3
0
3
0
4
2 feet
0
5
6
Severity score Fig 3: Bar graph shows the number and the percentage of feet having the normal and abnormal flows according to the severity score in all 24 feet with CTEV. Severity score 5 comprises 14 feet accounting for 58.3% of the CTEV group, among which 9 feet (37.5%) have normal arterial flow, and 5 feet (20.8%) have abnormal flow.
Table 1.
The proportion of vascular status pre and post Ponseti casting (n=24) Vascularity Post Ponseti casting p-valuea
Vascular status
Normal Vascularity Ponseti casting
Abnormal
17
0
Pre
0.031 Abnormal
a
Normal
6
1
. Binomial distribution – significant at p-value less than 0.05
S0958-2592(16)30138-9 http://dx.doi.org/doi:10.1016/j.foot.2017.05.003 YFOOT 1480
To appear in:
The Foot
Received date: Accepted date:
17-12-2016 7-5-2017
Please cite this article as: MUNAJAT Ismail, YOYSEFI Mehran, NIK MAHDI Nik Munirah.Deficient dorsalis pedis flow in severe idiopathic clubfeet.Does Ponseti casting affect the outcome?.The Foot http://dx.doi.org/10.1016/j.foot.2017.05.003 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Title: Deficient dorsalis pedis flow in severe idiopathic clubfeet. Does Ponseti casting affect the outcome?
Authors: Ismail MUNAJAT MBBS MMed* Mehran YOYSEFI MBBS MMed* Nik Munirah NIK MAHDI MBBS MMed¥
*
Department of Orthopaedics, School of Medical Sciences, Universiti Sains Malaysia (USM),
Kubang Kerian, 16150 Kota Bharu, Kelantan, Malaysia. ¥
Department of Radiology, School of Medical Sciences, Universiti Sains Malaysia (USM),
Kubang Kerian, 16150 Kota Bharu, Kelantan, Malaysia.
Corresponding author: Ismail Munajat, Department of Orthopaedics, School of Medical Sciences, Universiti Sains Malaysia (USM), Kubang Kerian, 16150 Kota Bharu, Kelantan, MALAYSIA Email : [email protected] ; Tel : +609-7676398 ; Fax : +609-7676389
Highlights:
Pirani severity scores of 5 and more are at higher risk of getting arterial deficiency
Dorsalis pedis artery is the one affected most
Ponseti casting is able to reconstitute the arterial flow in the majority of cases, which are initially deficient
Background Congenital clubfoot or Congenital Talipes Equinovarus (CTEV) is one of the most important congenital deformities in newborn. It is not a self-limiting disease; hence progressive feet deformity among untreated patients potentially affects the quality of life. Serial Ponseti manipulation and casting has been established as the most widely accepted treatment for CTEV over several years The severity of clubfoot has been correlated with the involvement of the soft tissue [1]. However, the relationship between the severity of the clubfoot and arterial deficiency has not been far investigated. Furthermore, a remarkable percent of the patients need a surgical intervention to release the contracted soft tissues and to facilitate the correction of the equines [2]. Deficiency in a specific artery in CTEV gives a signal to the orthopaedic surgeons to protect other dominant blood vessels during surgery. Furthermore, maintaining the corrected foot in a cast has to be well fitted and compliant to the regime. Studies on the association between arterial deficiency and clubfoot severity, and studies on the effect of Ponseti treatment on the arterial deficient clubfoot are still lacking. Therefore, the present study aims to investigate the association between severity of clubfoot and arterial deficiency as well as to find the effect of Ponseti treatment on the vascular status among feet with CTEV.
Method This prospective study was conducted from April 2011 to October 2012. A total number of 18 babies (24 feet) with congenital clubfeet and Pirani score ranging between 2 to 6 fulfilled the inclusion and exclusion criteria. Inclusion criteria were infants delivered with CTEV up to oneyear-old, babies who were never treated for CTEV elsewhere and population confined within the country. Exclusion criteria were patients who received unsuccessful or incomplete casting
treatment somewhere else, patients who had surgical correction before, syndromic patients with CTEV and patients who had other complex disorders such arthrogryposis, teratologic disorder and myelomeningocele. Eighteen normal babies (36 normal feet) were selected as control from postnatal ward. The severity of congenital clubfoot was assessed using Pirani severity score. The severity scores were grouped as follows; severity score 1(Pirani score 0.5 to 1.5), severity score 2(Pirani score 2 to 2.5), severity score 3(Pirani score 3 to 3.5), severity score 4(Pirani score 4 to 4.5), severity score 5(Pirani score 5 to 5.5) and severity score 6(Pirani score 6). Both study and control groups were subjected to Color Doppler Ultrasound for dorsalis pedis and posterior tibial arteries study before starting the Ponseti treatment. A single qualified radiologist performed the Color Doppler Ultrasound examination. For this purpose, Color Doppler Ultrasound machine (SIMENS-ACUSON S2000-USA) was employed. A normal artery is defined as an artery that is detectable and has antegrade flow while deficient artery is defined as an artery which is either not detectable or detected but has retrograde flow. All feet with CTEV underwent serial Ponseti manipulation and casting as a weekly basis until full correction. Second Color Doppler Ultrasound was performed in study group upon completion of Ponseti treatment just before applying the Dennis Brown Shoes as foot abduction brace. All data collection was recorded in SPSS (versions 20).
Results From 24 CTEV feet, 7(29.1%) had vascular abnormalities [Figure 1]. In these 7 feet, all dorsalis pedis had absent arterial flow [Figure 2a], while posterior tibial arteries were detectable with a normal antegrade flow [Figure 2c]. The remaining 17 CTEV feet (70.8%) had normal antegrade arterial flow. The arterial flow of dorsalis pedis and posterior tibial arteries were normal in all cases in the control group. Statistical comparison of the vascularity between study
and control group was not achievable; however, there was a noticeable difference in proportion between study and control group. All 7 CTEV feet with arterial abnormality were in the group of severity score 5 (71.4%) and 6 (28.5%). There was no arterial deficiency noted with severity score less than 5 [Figure 3]. The arterial abnormality and the severity of the Pirani score were not directly proportional. The mean of Pirani severity score in deficient vascular CTEV was 5.3, which was higher than the mean of Pirani severity in normal vascular CTEV (4.2). Analysis of these collected data, using Non-parametric Mann-Whitney test demonstrated that babies with higher severity score were associated with more abnormal vascularity compared with lower severity score (p=0.008). There was 85.7 % (6 of 7 feet) of arterial deficient feet reconstituted the blood flow after Ponseti treatment [Figure 2b] which was statistically significant (p= 0.031) as in table I. Only 1 foot remained arterial deficient despite full deformity correction after Ponseti treatment.
Discussion Several studies have been reported about the theories of pathogenesis behind CTEV [3, 4]. They had postulated the role of primary germplasm effect on the abnormality of the talus, but they have not found vascular abnormalities in their study. The vascular theory had been presented in clubfoot, which has explained that lack of anterior tibial artery leads to medial tightness and dysplasia of talus angle [4]. Studies have suggested a 3.7% to 12% prevalence of deficient dorsalis pedis arteries in normal feet [5, 6]. The prevalence of deficient dorsalis pedis artery in limbs with idiopathic clubfoot had been reported 84% in 16 feet with the age range of 1.3 to 13.5(average 6.3 years) using angiographic study [7]. Based on the data from above studies, deficient dorsalis pedis artery can still occur in the normal population in which the percentage may vary with different races and geographical areas. However, a study
comparing the prevalence of deficient posterior tibial artery in normal and in feet with CTEV is still lacking even though it may be less common. Edelson JG and Husseini N had encountered an incidence of pulseless vascularity (6.7%) in the severe clubfoot among children less than 3-years-old compared to the normal control (3.2%) [8]. An absent or anomalous posterior tibial artery is a very uncommon finding in patients with clubfoot and deficiency of posterior tibial artery is less common than dorsalis pedis artery in patients with congenital clubfoot [9, 10]. The exact aetiology on why the posterior tibial artery is less commonly involved remains unknown. In our opinion, due to the equinus and adduction deformities, dorsalis pedis artery is at a higher risk of being stretched and compressed over the deformed tarsal bones at the dorsum part of the foot compared to the posterior tibial artery at the posterior. In our study, there was no deficiency of posterior tibial arteries detected in the CTEV group. The posterior tibial artery was found to be absent in two patients at the time of an operative release procedure for clubfoot, and its arteriographic appearance of an absent posterior tibial artery was also studied [11]. Abnormal vascularity had been described as absent or retrograde flow [12]. Color Doppler Ultrasound is a perfect tool for assessing the presence of the arterial flow as well as the direction of the flow compared with conventional ultrasound. In our study, all of the arterial insufficiencies were detected as absent flow rather than retrograde flow. One of the critical initial assessments of CTEV is to determine the severity of the deformity. Some severity scoring systems have been described which include Lehman, Dimeglio and Pirani scoring systems. Scoring system should be practically simple, possible in a clinical setting, reliable, and able to envisage suitable plan for management [13, 14]. Pirani scoring system is chosen in this study because it is simple, fast and reliable. Furthermore, it does not use any radiation to complete the scoring unlike in Lehman scoring system. Although Dimeglio scoring is complex, however, this system is also one of the best-accepted scoring system [13].
Edelson JG and Husseini N had used Lehman’s scoring and a Doppler technique for a study on the arterial pulse in clubfoot and reported that the incidence of pulselessness increased with the severity and duration of deformity [8]. Their finding was rather consistent with our study whereby increasing the severity score was associated with increased incidence of arterial deficiency despite different severity scoring system used. However, our study revealed a higher percentage of arterial deficient feet (29.1%) in younger patients (less than 1-year-old) compared to only 7% in children under 3 years of their study. They also examined the relationship between the duration of deformity and the incidence of pulselessness which was good since it has never been studied before. However, to conduct a similar study now or near future on the duration of deformity might be less feasible since anxious parents tend to bring their babies with clubfeet earlier for treatment. A late presentation of clubfoot might be difficult to recruit for study owing to increasing public awareness and education towards clubfoot. Pulsed Color-Flow Doppler was used by Katz et al, in the analysis of arterial deficiency in idiopathic clubfoot and noted that the prevalence of deficiency of dorsalis pedis artery in clubfeet requiring surgery was 54% compared those that did not (20%) [12]. In contrast with our study, Katz et al, did not use any severity score to correlate with vascular deficiency but rather assuming that decision to treat a foot surgically was indicative of more severe involvement [12]. In our opinion, severe clubfeet which show poor progression with Ponseti casting warrant proper documentation of severity score once decision to discontinue casting has been made. A vascular assessment using Color Doppler Ultrasound can then be arranged before any surgical release. Several studies were attempted to find an effective way to demonstrate the lower limbs vascular malformation. Contrast angiography is presented as a gold standard for the diagnosis of arterial abnormalities [7]. The vascular pattern has been shown very well with this method. However, it is an invasive study with high risk of arterial damage, haemorrhage, ischemia and allergic
reaction. MRA have been applied for CTEV cases successfully, but contrast MRA is as invasive as contrast angiography if used for vascular assessment in CTEV [15, 16, 17]. Noncontrast MRA is a noninvasive method, but it has limitations such as time-consuming and needs for anaesthesia for babies. Therefore, Color Doppler Ultrasound was preferably chosen because of its safety and noninvasiveness during vascular assessment particularly in babies aged less than 15 weeks old like in this study. We also thought that Color Doppler Ultrasound was easy to use and radiation free. Initial Wave Doppler Ultrasound study on arterial blood vessel could not determine the difference in prevalence of vascular abnormality between CTEV cases and normal controls [8]. Pinto et al, later investigated the role of Color Doppler Ultrasound in assessing the vascular status in CTEV and they found that Color Doppler Ultrasound has not shown a significant variation of arterial morphology and flow speed between affected foot and normal contralateral side [17]. But they have noticed that patient with a larger diameter of anterior tibial artery had a better response to treatment, and more severe vascular abnormality of CTEV may be associated with the more resistant to deformity correction [17]. Based on above study, it seems that severe vascular abnormality is more likely to be associated with severe soft tissue involvement leading to a poor response to treatment, whereas, clubfeet with less vascular and soft tissue involvement may have a better response. There were few kinds of literature previously studied on the Doppler ultrasound used in the vascular assessment of CTEV. Yildirim T et al, evaluated the changes observed in the main arteries of the foot before and after the Ponseti technique using Doppler ultrasound [18]. It was found that Ponseti method resulted in normalisation of the arterial structures in extremities with congenital talipes equinovarus [2]. This finding was consistent with our study. However, we believe our study has an additional advantage as Color Doppler Ultrasound and Pirani severity
score were used. Compared to their study, we scored the clubfoot severity and analysed it with the patency of the arterial flow. There was a study by Merrill et al, who somewhat looked into arterial abnormalities in clubfoot not in early life presentation but rather when the clubfoot had recurrence [1]. They have shown that vascular abnormalities were present in all three patients with recurrent clubfoot, suggesting these anatomic abnormalities may be predictive of response to treatment [1]. However, that study was conducted in bigger children and adults aged from 6 to 60 years, and non-contrast MRA was used for vascular assessment instead of Color Doppler Ultrasound [1]. Based on above study, there will be a risk of recurrence in 6 feet with CTEV in the current study since the first Color Doppler Ultrasound revealed an arterial deficiency. A longer follow-up is needed to evaluate the outcome of these 6 clubfeet who resume the arterial flow after Ponseti treatment particularly in evaluating the risk of recurrence. The importance of this study is that when there is an absence of anterior tibial artery found during vascular assessment with Color Doppler Ultrasound, posterior tibial artery should be well protected if a surgical release of the clubfoot is needed in the future. If both anterior and posterior tibial arteries are absent during clubfoot assessment which is unusual, it will serve as a warning of potential precarious circulation to the foot, and peroneal artery may be dominant [11]. Severe congenital clubfoot with high Pirani severity score requiring surgery may warrant preoperative vascular assessment using Color Doppler Ultrasound to detect any arterial deficiency associated with the severity of the deformity. It may be beneficial to document foot vascularity using Color Doppler Ultrasound, particularly in severe CTEV before starting Ponseti casting.
Conclusion In conclusion, arterial deficiency is found in 29.1% of CTEV feet in the current study and all affected vessels are dorsalis pedis arteries. Pirani severity scores of 5 and more are at higher risk of getting an arterial deficiency. As much as 85.7% of arterial deficient CTEV feet regain their blood flow after Ponseti treatment. We believe the dorsalis pedis artery is present since birth with normal morphology, however, the deformity of the feet compresses it and makes it less patent, particularly with more severe deformity. We also believe that correcting the deformity alleviates the compression, thus, restores the patency of the arterial blood flow. Ponseti treatment is able to correct the deformity as well as to reconstitute the arterial flow in the majority of cases which are initially deficient.
Acknowledgement This study was approved by The Research Ethics Committee (Human) on 8th May 2011. This study was not funded by any organisation.
References [1] Merrill LJ, Gurnett CA, Siegel M, Pirani S, Dobbs MB. Vascular abnormalities correlate with decreased soft tissue volumes in idiopathic clubfoot. Clinical Orthopaedics and Related Research 2011; 469: 1442-1449. [2]
Chu A, Lehman WB. Persistent clubfoot deformity following treatment by the Ponseti
method. Journal of Pediatric Orthopaedics B 2012; 21:40-46 [3] Irani RN, Sherman MS. The pathological anatomy of clubfoot. The Journal of Bone and Joint Surgery Am 1963; 45: 45-52. [4]
Hootnick D, Packard Jr D, Levinsohn E, et al. The anatomy of a congenitally short limb
with clubfoot and ectrodactyly. Teratology 1984; 29: 155-164. [5]
Sarrafian S. Functional anatomy of the foot and ankle. Anatomy of the foot and ankle,
descriptive, topographic, functional. 2nd ed. Philadelphia: JB Lippincott; 1993; 474-602. [6] Huber JF. The arterial network supplying the dorsum of the foot. The Anatomical Record 1941; 80, 373-391. [7]
Greider TD, Siff S, Gerson P, Donovan M. Arteriography in club foot. The Journal of
bone and joint surgery Am 1982; 64: 837. [8]
Edelson JG, Husseini N. The pulseless club foot. J Bone Joint Surg Br 1984; 66: 700-
702. [9] Quillin SP, Hicks ME. Absent posterior tibial artery associated with clubfoot deformity: an unusual variant. Journal of Vascular and Interventional Radiology 1994; 5: 497-9. [10] Kitziger K, Wilkins K. Absent posterior tibial artery in an infant with talipes equinovarus. J Pediatr Orthop 1991; 11: 777-8. [11] Dobbs MB, Gordon JE, Schoenecker PL. Absent Posterior Tibial Artery Associated with Idiopathic Clubfoot: A Report of Two Cases. The Journal of Bone and Joint Surgery Am 2004; 86: 599-602.
[12]
Katz DA, Albanese EL, Levinsohn EM, Katz, Hootnick DR, Packard DS, Grant WD,
Mann KA, Albanese SA. Pulsed color-flow Doppler analysis of arterial deficiency in idiopathic clubfoot. Journal of Pediatric Orthopaedics 2003; 23: 84-87. [13]
Wainwright AM, Auld T, Benson MK, Theologist TN. The classification of congenital
talipes equinovarus. Journal of Bone & Joint Surgery, British Volume 2002; 84: 1020-1024. [14]
Dyer P, Davis N. The role of the Pirani scoring system in the management of clubfoot
by the Ponseti method. The Journal of Bone and Joint Surgery Br 2006; 88: 1082-1084. [15]
Kruse L, Gurnett CA, Hootnick DR, Dobbs MB. Magnetic resonance angiography in
clubfoot and vertical talus: a feasibility study. Clinical Orthopaedics and Related Research 2009; 467: 1250-1255. [16]
Marckmann P, Skov L, Rossen K, et al. Nephrogenic systemic fibrosis: suspected
causative role of gadodiamide used for contrast-enhanced magnetic resonance imaging. Journal of the American Society of Nephrology 2006; 17: 2359-2362. [17] Pinto JA, Blumetti FC, Iha LAN, Terasaka MK, Sodré H, Ishida A. Evaluation of arterial anatomy in congenital clubfoot with color doppler ultrasound. Acta Ortopédica Brasileira 2008; 16: 270-274. [18]
Yildirim T, Bursali A, Tonbul M, Sakizlioglu SS, Camurcu Y. Does the Ponseti
technique affect the vascular development in patients with congenital talipes equinovarus? J Pediatr Orthop B 2015; 24: 6-10.
40
Abnormal flow
Normal flow
36
35
Number of feet
30
25
20 17 15
10 7 5
0 0
CTEV GROUP
CONTROL GROUP
Fig 1: Bar graph shows the proportion of feet with arterial blood flow abnormality in CTEV and control groups
b
a
LT POSTERIOR TIBIAL A
c
Fig 2: Color Doppler Ultrasound shows the deficient of blood flow in dorsalis pedis artery prior to Ponseti casting (a), the presence of blood flow in dorsalis pedis artery after completed Ponseti casting (b) and the normal blood flow in posterior tibial artery prior to Ponseti casting (c).
Normal flow
Abnormal flow
40
37.5
35
9 feet
Percentage
30 25 20.8
20 15
12.5
10
0
0
1
4 feet
3 feet
4.1
5
0
5 feet
16.7
1 foot
0
2
8.3
0
3
0
4
2 feet
0
5
6
Severity score Fig 3: Bar graph shows the number and the percentage of feet having the normal and abnormal flows according to the severity score in all 24 feet with CTEV. Severity score 5 comprises 14 feet accounting for 58.3% of the CTEV group, among which 9 feet (37.5%) have normal arterial flow, and 5 feet (20.8%) have abnormal flow.
Table 1.
The proportion of vascular status pre and post Ponseti casting (n=24) Vascularity Post Ponseti casting p-valuea
Vascular status
Normal Vascularity Ponseti casting
Abnormal
17
0
Pre
0.031 Abnormal
a
Normal
6
1
. Binomial distribution – significant at p-value less than 0.05