Cervicothoracic Spinal Dysraphism: Unravelling the Pandora's Box.

INTRODUCTION: Cervicothoracic spinal dysraphism (CTSD) is relatively rare with reported incidence of 1%-6.5%. The entity has a separate spectrum of associations with other anomaly such as split cord malformation, Chiari malformation, and corpus callosum agenesis as compared with its lumbosacral counterpart. In this study, we have highlighted the associated anomalies (AAs). To the best of our knowledge, this study is one of the largest series reported before.
MATERIALS AND METHODS: In this study, we included the patients with spinal dysraphism operated between December 2007 and December 2017 at the Department of Neurosurgery. All patients underwent neurological and radiological examinations followed by surgical excision of the sac and exploration of the intradural sac. Neurological, orthopedic, and urological abnormalities were analyzed in our retrospective description. The last available follow-up in hospital records was taken for outcome assessment.
RESULTS: Of 34 cases, 18 were women and 16 were men. Seven of nine patients in cervical group had AAs, whereas 22 of 25 patients in dorsal group had AA. In this study, we taken 6 patients with Chiari malformation, 4 with corpus callosum agenesis, 7 with hydrocephalus, and 16 with split cord malformation. The follow-up ranges from 1 year to 11 years with a mean of 59.45 months.
CONCLUSION: The management strategy and association with other congenital anomalies separate CTSD as different clinical entity as compared with their lumbosacral counterparts. These patients show relatively favorable outcome with regard to neurological, orthopedic, and urological symptoms. Early surgical intervention after proper radiological and clinical evaluation is recommended. Copyright:

Cervicothoracic spinal dysraphism (CTSD) is a separate clinical entity.

CTSD has higher incidence of associated anomalies.

The common clinical presentation is swelling without motor or sensory symptoms.

These patients have better surgical outcome.

Introduction

Spinal dysraphism of the cervical and the upper thoracic region (CTSD) is relatively rare with reported incidence of 1%–6.5%.[123] Children with these lesions are more likely to have near normal motor functions as compared with patients with lesions at lower regions (lower thoracic and lumbosacral) of the spine.[1234] The incidence of associated anomalies (AAs) in CTSD has been variedly reported and no study has focused on the AAs in the subsets of these patients.[1] In this study, we present our experience of patients with CTSD with special emphasis on the AAs (both neural and extra-neural).

Material and Methods

We included all patients with spinal dysraphism of CTSD operated between December 2007 and December 2017 at the Department of Neurosurgery. Upper thoracic spine was defined as at or above the sixth thoracic vertebra. All cases were retrospectively studied and all available data including age, sex, level of lesion, type of lesion, and AAs were recorded from hospital case records, outpatient files, and the hospital information system.

The patients with age over 16 years were excluded from the study. Written informed consent was obtained from the all the patients to use clinical and radiological details for publication. Ethical approval for this study was obtained from the ethics committee of our institution (Approval no. IEC 2017-95-MCh-EXP). The neurological condition at the last follow-up was noted from the records and when needed the relatives of the patients were contacted telephonically and the condition of the patients was ascertained over the phone.

In this study, 14 patients in had isolated swelling and 58.8% (n = 20) were less than 2 years old, so it was difficult to analyze them using standard scales such as American spinal injury association score. The deficit-free status in an operated case for swelling in cervical and thoracic region was considered as improved. The patients with new-onset neurological deficits, including urinary complaints or deterioration in motor power, were considered as deteriorated. Difficulty in walking included spastic weakness and lower motor neuron type weakness according to age of child, but excluded any orthopedic difficulty.

Results

Demographic profile

A total of 225 patients with spinal dysraphism were operated between December 2007 and December 2017. Among them, 34 patients with CTSD (9 [26.5%] were of cervical region and 25 [73.5%] were of thoracic region) were included in the study. The mean age at time of admission was 51.5 months (range 1–192 months). In total, 47.1% (n = 16) of cases were under age of 1 year and 55.9% of cases were under age of 2 years (n = 19). Six cases (17.6%) were age of over 10 years. There were 18 women and 16 men (4 of 9 women were in cervical and 14 of 25 women were in thoracic).

Clinical features

The most common presentation was isolated swelling (n = 14; 41.2%) [Figures 1 and 2]. Six patients (17.6%) had both swelling with constipation and walking difficulty. Four patients (11.8%) had swelling with constipation, but without walking difficulty. Fifteen patients had difficulty in walking (four patients were of age less than 1 year, 6 were of age between 1 and 10 years, and five were of age over 10 years). The urinary involvement (sphincteric involvement based on uroflowmetry [n = 4], in the form of retention with overflow [n = 2], or incontinence with loss of urinary bladder sensations [n = 2]) was found in eight patients.

Figure 1

Representative photographs of three patients in our series with CTSD

Figure 2

Representative photographs of two patients in our series with CTSD

One patient with cervical CTSD (cCTSD) had ulcer in the left great toe but a detailed sensory examination was not possible because of the small age of the child. Two or more levels were involved in five cases (one in cCTSD and four in tCTSD).

The AAs in patients with CTSD are presented in [Table 1].

Table 1

Associated anomalies in patients with cervical (N = 9) and upper thoracic (N = 25) spinal dysraphism in our series

Author name	Men	Women
Orakdogen et al.[12]	3	4
Kasliwal et al.[16]	5	5
Andronikou et al.[4]	1	5
Habibi et al.[1]	9	7
Duz et al.[18]	5	0
Salomao et al.[3]	11	7
Delashaw et al.[5]	0	4
Huang et al.[6]	6	4
Meyer-Heim et al.[2]	4	1
Pang et al.[7]	5	5
Total	49	42

Chiari malformation (CM)

There were six patients with CM (four in cervical group and two in dorsal group). Four of them presented with urinary difficulties and all six patients had swelling over the back. Of these 6, 5 had Type II CM and 1 had Type III CM. Three patients had difficulty in walking and one (1/6) patient had developmental delay. Among them, three (50%) had corpus callosum agenesis (CCA), whereas three (two in cervical group and one in dorsal group) had hydrocephalus. Of these, two patients (33.3%), both were at the same level as the swelling, had associated split cord malformation (SCM) and one had foot anomaly.

CCA

Of 34 patients, four (11.8%) had associated CCA. Three of these four patients belonged to the cervical group and one to dorsal myelomeningocele. Interestingly, all three patients in cervical group were at level C2 (high cervical). Among these four patients, three patients had urinary problems, whereas only one (dorsal group) had limb shortening. Three had associated SCM (two in cervical group and one in dorsal group). Two patients had CM and SCM associated with CCA(one in cervical and one in dorsal group). In addition, two patients had an associated hydrocephalus, whereas one had developmental delay. All four patients had syrinx.

Dermal sinus

Of 34 (23.5%) patients, eight had dermal sinus tract (all in dorsal group). Among these eight, two (25%) were men and the rest were women. Two patients had urinary symptoms and three had tuft of hairs. Six of these patients had dermal sinus tract, which was surgically excised. Two had an associated dermoid cyst. One had Hirschsprung’s disease (HD) and the other had associated neuroenteric cyst. Four (50%) had associated SCM. Of these four cases, three had the bony spur at the level of the dermal sinus. Two had associated hydrocephalus (one had associated dermoid cyst) and the other had foot anomaly).

Hydrocephalus

Of 34 (20.6%) patients, seven had hydrocephalus (three in cervical group and four in dorsal group). Of these seven, four presented with swelling and three had no swelling. Three (42.8%) had associated urinary problems, whereas two had dimple over the back and one had ulcer over the foot. Among these seven patients, three had associated CM and four (57.14%) had associated SCM (two each in cervical and dorsal group). Two had associated CCA (one in cervical group and one in dorsal group).

Orthopedic anomalies

Fifteen patients had orthopedic anomalies. Among them, two were in the cervical group and thirteen were in the dorsal group. Of these 15 cases, six (40%) were men and the rest were women.

One patient in cervical group had foot anomaly associated with CM. Six patients had foot anomalies in dorsal group and four of these six patients needed splintage with regular physiotherapy, whereas one patient underwent additional orthopedic surgery. One patient had pes cavitum. These patients were followed up and needed additional rehabilitative and orthopedic care.

Of 34 patients, six had spinal curvature anomaly either alone or associated with some other orthopedic anomaly. Of these six, one belonged to cervical group and rest five were in the dorsal group. Two patients had an isolated curvature anomaly (kyphoscoliosis), whereas three had Klippel–Feil syndrome. One patient of dorsal group had curvature anomaly in form of kyphoscoliosis toward left along with absent upper five ribs on the same side. These types of anomalies belong to a spectrum of costovertebral agenesis and are popularly known as Jarcho–Levin syndrome.

SCM

Of 34 patients, 16 (47.1%) were found of SCMs. Of 16 patients, 2 had Type I SCM and the rest 14 had Type II SCM (4 in cervical group and 12 in the dorsal group). Three (18.75%) had associated CCA and two (12.5%) had associated CM (both Type II), but none required additional surgery for the same. Four patients (two each in cervical group and dorsal group) had associated hydrocephalus. None of the patients deteriorated in postoperative period and follow-up. SCMs are commonly associated with CTSD.

Hydromyelia

Of 34 patients, 13 (38.2%) patients had syrinx. Of these 13, five patients were in the cervical group and eight were in the dorsal group. In the cervical group, only in four of five cases had the syrinx till C2. Four (30.8%) had an associated CM. Of these four patients, three belonged to cervical group and one to dorsal group. Furthermore, of the three patients of cervical group, one had Type III CM and the other two had Type II CM. Of 13 cases, four (30.8%) had associated CCA. Of these four patients, three belonged to cervical group and one to dorsal group. Of 13 cases, nine (69.2%) had associated SCM. Interestingly, all nine patients had Type II SCM. Five (38.4%) had associated hydrocephalus. Of these five, three belonged to cervical group and two belonged to dorsal group.

Surgical Findings

All patients underwent surgical excision of the sac and exploration of the indradural sac using the standard microsurgical technique. Laminotomy was performed at least one level above and one level below the involved segments so as to observe the normal dural tube. Multiple level involvement necessitated laminectomy at all the involved sites. A two-level laminectomy was performed in the two patients (SCM was found to be at a distant level in both the patients). In 31 patients, we found a tubular stalk protruding from the posterior surface of the cord and it was contained in the sac. The stalk penetrated the sac through a defect in the posterior midline structures and was adhered to the wall of the cyst either in the centre of the dome or eccentrically. The stalk was cut a few millimeters from the spinal cord.

A cystic mass was found inside the protruding dural sac in two patients. The outer cyst was communicating with the subarachnoid space and the inner cyst was communicating with the hydromyelic spinal cord (myelocystocele [MCC]) and one patient had only herniation of the meninges filled with cerebrospinal fluid (CSF) without any neural tissue. Fourteen cases had SCM with bony spur at an adjacent level and two cases had the SCM at a different level necessitating two-level laminectomy. The other two patients had fibrous band with SCM at adjacent level to the cystic dysraphism. One patient had both fibrous and bony spur.

Postoperative Course

Three patients had postoperative CSF leak (two patients were of cervical region and one had thoracic region lesion). One of them underwent reexploration, whereas the CSF leak in the other two patients subsided on acetazolamide and wound aspiration with daily dressing. Two patients deteriorated and one patient improved in follow-up period. One patient was operated elsewhere at an age of 2 years for swelling and was referred and admitted at our centre after 8 years for cervical cord tethering.

Follow-up

The mean follow-up in this study was 59.45 ± SD 38.2 months (95% confidence interval for mean 46.3–72.5 months; median follow-up 60 months, range 1–11 years).

Discussion

There are only a few series of CTSD in the literature and none of the series focuses on anomalies associated with these uncommon dysraphisms.[123456789] The largest series presented 18 patients of cervical and upper thoracic spinal dysraphisms and to the best of our knowledge, our series with 34 patients is one of the largest series on this entity.[1210]

A total of 225 cases of spinal dysraphisms presented to our centre over the 10 years’ study period and the prevalence of CTSD was 34/225 (15.1%) The reported incidence has varied from as less as 1.6% to as high as 9%.[1711] In our series, the prevalence is 15.1%, which is higher than the reported in the literature. The high prevalence in the series by Habibi et al. as well as in our series may be attributed to the fact that many patients with distal location of cystic dysraphism had severe neurological deficits and so parents did not want admission or surgery. In our series, there was no significant sex predilection (male-to-female ratio––17:18). In a series by Salamao et al.,[3] there was female predilection, but in a series by Habibi et al.,[1] there was male preponderance. By combining all major series, there appears to be a slight male predilection [Table 2].

Table 2

Sex ratio of patients in different studies published in the literature

S. no.	Study	CM	SCM	HCP	Syrinx	Curvature anomaly	CCA	Others
1	Orakdogen et al.[12]	2/7	1/7	2/7	1/7	--	--
2	Kasliwal et al.[16]	2/10	1/10	5/10	3/10			Subluxation of C1 over C2 1/10
								Thoracolumbar MMC in 2/10
3	Andronikou et al.[4]	4/6	3/6	2/6	2/6	--	2/6	Developmental delay 1/6
4	Habibi et al.[1]	4/16	1/16	8/16	2/16	--	--	Sacral MMC in 1, LipoMMC in 1, mature teratoma in 1
5	Duz et al.[18]	--	1/5	--	--	--	--	Klippel–Feil syndrome 1/5
6	Salomao et al.[3]	7/18	1/18	7/18	6/18	--		3/18 had impaired intellectual, Rib anomaly in 1, PCKD in 1, Klippel–Feil syndrome in 1, dermoid in 1, spina bifida occulta in 1
7	Delashaw et al.[5]	2/4	1/4	2/4	3/4	1/4	--	Klippel–Feil syndrome 2/4
								Subluxation C1 over C2 1/4
8	Huang et al.[6]	1/10	1/10	3/10	--	--	--	Sacral spina bifida occulta in 1
9	Meyer-Heim et al.[2]	3/5	--	2/5	--	1/5	--	Pes equines 2/5
								Mental retardation 2/5, periventricular Heterotopias in 1, ADHD 1/5, FSH muscular dystrophy in 1, thickened filum with lipoma in 1
10	Pang et al.[7]	4/9	4/9	6/9	--	--	--	LDM 5/9
11	Steinbok et al.[14]	5/8	--	5/8	3/8	--	--
12	Sun et al.[9]	5/8	--	5/8	3/8	1/8	--	Hemivertebrae 1/8, block vertebra in 1, thoracolumbar MMC in 1
13	This study cervical cases	4/9	4/9	3/9	5/9	1/9	3/9	8/25 had dermal sinus
								2/25 had chest wall deformity
14	This study thoracic	2/25	12/25	4/25	8/25	5/25	1/25	Multiple level involvement in 2
								Neuroenteric cyst in 1 and dermoid cyst in 1
	Total	45/135	30/119	54/135	36/111	9/51	6/40
		(33.3%)	(25.2%)	(40.0%)	(32.4%)	(17.6%)	(15.0%)

Associated Anomalies

CTSD are usually associated with other developmental anomalies. CM is the leading congenital anomaly associated with these lesions.[12] The other anomalies associated with these lesions are syringomyelia, hydrocephalus, SCM, lipomyelomeningoele, thickened filum terminale, Klippel–Feil anomaly, and hemivertebrae.[2121314]

CM

The incidence of CM varies from 10% to as high as 66.67% in various reported series.[49101119] In our series, the incidence was nearly 17% (6/34). The relatively low incidence in our series could be because of the fact that majority of our patients were of the thoracic group in which the incidence was only 2/25 (8%). If only the cervical lesions in our series were taken into consideration, the incidence of CM was 4/10 (40%) which is more in tune with the literature. On combining all major series [Table 3], the overall incidence of CM is 33% (45/135). Whether all patients with CM require surgery for CM also is not clear in the literature as the previous series does not clearly mention whether CM was operated on or not. It appears that CM was not operated on in majority of series.

Table 3

Comparative data analysis of associated anomalies in previous series and overall incidence

Patients	CM	SCM	HCP	Dermal sinus	CCA	Syrinx	Foot anomaly	Kyphoscoliosis	Others
Cervical group
1		y	y			y		y
7 m/F
2		y			y	y
5 m/F
3	y	y	y		y	y
16 y/F
4		y							High arched palate
6 y/M
5
1 y/F
6	y						y
6 m/M
7
4 m/M
8	y		y			y
7 m/M
9	y				y	y
3 y/M
Thoracic group
1		y
16 y/M
2		y
16 y/F
3		y		y			y	Y	Dermal sinus
18 m/M									Hirschsprung’s disease
4			y				y
9 y/F
5		y				y	y
1 m/M
6		y					y		Hemivertebrae at D8-9 bony and fibrous spur
2 y/F
7								Y	Fibrous spur
1 y/F									Lower ribs on left side absent
8				y		y
6 m/F
9		y		y		y
11 y/F
10	y	y	y		y	y
2 y/M
11		y				y	y		Pes cavitaum
8 y/F
12		y
14 y/F
13		y	y	y		y
6 m/F
14							y
25 m/M
15									Swelling at D5 level
14 y/M
16									Swelling at D4 level
1 m/M
17			y	y				y
6 m/F
18									Swelling at D2-3 level
1 m/M
19	y
1 m/F
20		y		y
6 y/F
21				y
1 y/M
22								y
6 y/M
23								y
1 m/F
24				y		y			Neuroenteric cyst
3 y/F
25		y				y
3 y/M

m/F is months (age) / Female (Gender), y/F is years (age) / Female (Gender), y/m is years (age) / Male (Gender), m/M is months (age) / Male (Gender), y is Yes (present)

Hydrocephalus

The incidence of hydrocephalus in literature ranges from nearly 28% to 66%.[71217] The overall incidence of hydrocephalus if all the major series are combined is nearly 40% [Table 3]. In series by Steinbok and Cochrane,[20] there was a perfect correlation between hydrocephalus and Type II CM but such correlation was not seen in series by Pang et al.[721] Even in our series, of six patients with CM only three had associated hydrocephalus. In series by Salomao et al.,[3] of seven cases of Type II CM, five had hydrocephalus (HCP). The embryogenesis of Type II CM and HCP in CTSD appears to be different and this is reflected in the lack of perfect association between the two. It appears that altered CSF flow in the herniated sac might be responsible for the development of HCP in these cases.

HCP has also been associated with the presence of MCC. In series by Habibi et al.,[1] both cases of MCC had HCP and similar finding was seen in series by Salomao et al.,[3] in which all three cases of MCC had associated HCP. However, in series by Andronikou et al., of three cases of MCC, only one had HCP. In our series, only one of two cases of MCC had hydrocephalus.[4]

In our series, all except one patient required diversion procedure in form of ventriculoperitoneal shunt. Similar need for diversion procedure in other series was seen in which almost all patients required diversion surgery.[78919202122]

CCA

The majority of series have not reported any association of CCA with CTSD but in series of six patients by Andronikou et al.[4], the authors found thin corpus callosum in two of their patients. Interestingly, all the cases of cervical group had cystic dysraphism at C2 level, indicating that a higher level might be more commonly associated with CCA. The fact that of 25 cases of thoracic CTSD in our series, only 1 had CCA, also points to fact that CCA is more likely to be associated with higher level of involvement. The overall incidence of CCA, if all the major series are combined, is nearly 15% [Table 3].

SCM

The incidence of SCM in the literature varies from as low as nearly 5% to as high as 50%.[418] In our series, 16 cases of 34 had associated SCM (47.1%). The overall incidence of SCM on combining all major series was 25.2% (30/119) [Table 3]. The incomplete fusion of the posterior part of the neural tube would give rise to a limited dorsal myeloschisis (LDM). The difference between LDM and a classical myelomenigocele is the degree of neurulation and a persistent endomesenchymal tract would be the cause of Type II SCM.

Bony spinal anomalies

Various bony anomalies have been reported with CTSD such as Klippel–Feil syndrome and hemivertebra.[12] We encountered bony abnormalities in the form of curvature anomalies (kyphoscoliosis), Klippel–Feil syndrome, hemivertebra, and foot anomalies. The majority of these cases were seen in the thoracic group. The most common bony anomaly encountered in our series was kyphoscoliosis and all except one had thoracic lesions. Curvature anomalies of the spine have also been reported in other series.[202122]

Foot deformity was seen in seven patients in our series. Foot deformity in the form of pes equinus (two of five cases) has also been reported in Meyer-Heim et al.[2] Hemivertebra was seen in two of our cases and another case was reported by Sun et al.[9] Rib anomalies also occasionally occur in CTSD.[15] Rib anomalies were seen in two of our patients. One patient had pes cavitum and in another patient there was absence of five ribs. Subluxation of C1 and C2 has also been reported but we did not encounter this anomaly in our study.[516]

Other anomalies

The impaired mentation has been reported in association with CTSD.[234] Two of our patients had developmental delay. Other reported associations are mental impairment, attention-deficit hyperactivity disorder (ADHD), and hindbrain herniation.[23] We encountered neuroenteric cyst in one case and a dermoid cyst in another case. Such tumors in association with CSDCT, though rarely, have been reported in the literature.[13] Polycystic kidney disease (PCKD) was reported in one case in series by Salomao et al. and one case, facioscapulohumeral dystrophy was reported in series by Meyer-Heim et al.[2] This case also had associated ADHD. One case in the same series also had periventricular heterotopias.

Conclusion

Cystic dysraphisms of CTSD are relatively uncommon lesions. Various anomalies are associated with these entities. The AAs are not only restricted to the neural structures but occasionally also involve extra-neural substrates. The most common anomalies associated are CMs, hydrocephalus, and hydromyelia. Tumors might also be found in association with these lesions in some rare cases. The appropriate imaging should be performed in these cases so as not to miss out on other anomalies.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.