Operative treatment of unstable injuries of the cervicothoracic junction

Awake Cranial Traction and Isolated Anterior Cervical Discectomy and Fusion in the Treatment of Traumatic Subaxial Cervical Facet Joint Dislocations: Analysis of a Cohort of 70 Patients and Predictors of Surgical Failure

BACKGROUND

Cervical facet dislocations are among the most common traumatic spinal injuries. The management of this type of lesions is still controversial. The objective of the present study was to analyze the results of subaxial cervical facet dislocations submitted to an isolated anterior cervical discectomy and fusion (ACDF) after attempted closed reduction with cranial traction and to identify risk factors for treatment failure.

METHODS

All patients who were operated on in a tertiary trauma center during an 11-year period (2008-2018) for traumatic single-level cervical facet joint dislocation (AO C F4 injuries) were retrospectively reviewed. Age, use of cranial traction, dislocation characteristics, neurologic injury, surgical data, and follow-up records were reviewed. A minimum of 18 months follow-up was required.

RESULTS

A total of 70 patients with a mean age of 56 years (18-90) (72% men) were identified. The C6-C7 level was the most frequently affected (36/70 cases). Spinal cord injury (SCI) was present in 34% of the cases. Bilateral dislocations and rigid spines were risk factors for SCI. Cranial traction was performed in 59 cases with success in 52 cases (88%). There were 3 failures after anterior fusion, which required revision surgery with a 360° fusion, all occurring at the C7-T1 level.

CONCLUSIONS

Cranial traction of the cervical spine is an effective and fast way to achieve closed reduction of cervical facet dislocations. After successful reduction, ACDF, as a single procedure, offers an excellent surgical option. All cases of failure occurred at the C7-T1 level, suggesting that a 360° fusion may be needed at this level.

LEVEL OF EVIDENCE: 3

Efficacy of Early (≤ 24 Hours), Late (25-72 Hours), and Delayed (>72 Hours) Surgery with Magnetic Resonance Imaging-Confirmed Decompression in American Spinal Injury Association Impairment Scale Grades C and D Acute Traumatic Central Cord Syndrome Caused by Spinal Stenosis

The therapeutic significance of timing of decompression in acute traumatic central cord syndrome (ATCCS) caused by spinal stenosis remains unsettled. We retrospectively examined a homogenous cohort of patients with ATCCS and magnetic resonance imaging (MRI) evidence of post-treatment spinal cord decompression to determine whether timing of decompression played a significant role in American Spinal Injury Association (ASIA) motor score (AMS) 6 months following trauma. We used the t test, analysis of variance, Pearson correlation coefficient, and multiple regression for statistical analysis. During a 19-year period, 101 patients with ATCCS, admission ASIA Impairment Scale (AIS) grades C and D, and an admission AMS of ≤95 were surgically decompressed. Twenty-four of 101 patients had an AIS grade C injury. Eighty-two patients were males, the mean age of patients was 57.9 years, and 69 patients had had a fall. AMS at admission was 68.3 (standard deviation [SD] 23.4); upper extremities (UE) 28.6 (SD 14.7), and lower extremities (LE) 41.0 (SD 12.7). AMS at the latest follow-up was 93.1 (SD 12.8), UE 45.4 (SD 7.6), and LE 47.9 (SD 6.6). Mean number of stenotic segments was 2.8, mean canal compromise was 38.6% (SD 8.7%), and mean intramedullary lesion length (IMLL) was 23 mm (SD 11). Thirty-six of 101 patients had decompression within 24 h, 38 patients had decompression between 25 and 72 h, and 27 patients had decompression >72 h after injury. Demographics, etiology, AMS, AIS grade, morphometry, lesion length, surgical technique, steroid protocol, and follow-up AMS were not statistically different between groups treated at different times. We analyzed the effect size of timing of decompression categorically and in a continuous fashion. There was no significant effect of the timing of decompression on follow-up AMS. Only AMS at admission determined AMS at follow-up (coefficient = 0.31; 95% confidence interval [CI]:0.21; p = 0.001). We conclude that timing of decompression in ATCCS caused by spinal stenosis has little bearing on ultimate AMS at follow-up.

Traumatic Fracture: Dislocation of Cervicothoracic Junction-Grand Round Presentation of C7-T1 Instabilities and Different Instrumentation Techniques

Introduction

Acute traumatic cervicothoracic junction spinal lesions are rare disorders and poorly documented. We report a case of a traumatic cervicothoracic fracture-dislocation. We present our experience in the operative treatment of an unstable fracture-dislocation at the cervicothoracic junction. Materials and Method. A seventy-year-old man was transferred to our hospital. We found paresthesia in the corresponding dermatome of C7 and C8 bilaterally. Initial CT scan shows vertebral body fracture of T1 with retropulsion into the spinal canal and anteroposterior dislocation of cervicothoracic junction type C according to AOSpine subaxial injury. Traumatic disc material at C7-T1 was removed by anterior cervical discectomy and fusion of C6-T2. Fixation was done from C6 to T2 in the prone position.

Results

At one-year postoperative follow-up, radiographs revealed bony fusion at the level of C7-T1, and the patient had no major functional disability.

Conclusion

We opted for the ventral-dorsal approach in our case for maximum stabilization and to prevent mechanical complications.

Reoperation rates for symptomatic nonunions in posterior cervicothoracic fusions with and without bone morphogenetic protein in a cohort of 450 patients

OBJECTIVE

Fusions across the cervicothoracic junction have been challenging because of the large biomechanical forces exerted resulting in frequent reoperations for nonunions. The objective of this study was to investigate a retrospective cohort using chart review of posterior cervicothoracic spine fusions with and without bone morphogenetic protein (BMP) and to determine the reoperation rates for symptomatic nonunions in both groups.

METHODS

Between January 2009 and September 2013, posterior cervicothoracic spine fusion cases were identified from a large spine registry (Kaiser Permanente). Demographics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Reoperations for symptomatic nonunions were adjudicated via chart review. Logistic regression was used to estimate odds ratios and 95% confidence intervals. Kaplan-Meier curves for the non-BMP and BMP groups were generated and compared using the log-rank test.

RESULTS

In this cohort there were 450 patients (32.7% with BMP) with a median follow-up of 1.4 years (interquartile range [IQR] 0.5–2.7 years). Kaplan-Meier curves showed no significant difference in reoperation rates for nonunions using the log-rank test (p = 0.088). In a subset of patients with more than 1 year of follow-up, 260 patients were identified (43.1% with BMP) with a median follow-up duration of 2.4 years (IQR 1.6–3.3 years). There was no statistically significant difference in the symptomatic operative nonunion rates for posterior cervicothoracic fusions with and without BMP (0.0% vs 2.7%, respectively; p = 0.137) for more than 1 year of follow-up.

CONCLUSIONS

This study presents the largest series of patients using BMP in posterior cervicothoracic spine fusions. Reoperation rates for symptomatic nonunions with more than 1 year of follow-up were 0% with BMP and 2.7% without BMP. No statistically significant difference in the reoperation rates for symptomatic nonunions with or without BMP was found.

Construct Type and Risk Factors for Pseudarthrosis at the Cervicothoracic Junction

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The primary goal is to compare the clinical results of 2 types of constructs commonly used at the cervicothoracic junction: small rods (3.2-mm/3.5-mm rods) or transitional constructs. The secondary goal is to perform a case-control study of risk factors for pseudarthrosis at the cervicothoracic junction.

SUMMARY OF BACKGROUND DATA

Various constructs have been used to stabilize across the cervicothoracic junction; however, no study to date has objectively compared their outcome. Our hypothesis was that both constructs would have similar fusion and complication rates.

METHODS

A retrospective review of a prospectively collected database revealed 135 patients with the aforementioned constructs and having followed up with imaging at 6 months, 12 months, and 24 months. Univariate analysis comparing the 2 different construct groups was performed. Multivariate analysis for risk factors of pseudarthrosis was also performed.

RESULTS

There were a total of 10 patients with pseudarthrosis at 2-year follow-up. There was no difference in pseudarthrosis rate between the small rods (7%) and transitional constructs (8.6%) (P = 0.99). The overall construct lengths were similar (5.8 levels in small rods, 6.7 levels in transitional construct). Blood loss was higher in transitional constructs (574 ± 69 mL) than in small rods (236 ± 53 mL) (P < 0.001). Transitional constructs also had longer operating times (249 min) than small rods (207 min) (P < 0.03). Overall complication rate was higher in the transitional constructs (P < 0.03). Tobacco use, corpectomy, lack of an anterior construct, and construct length were all risk factors for cervicothoracic junction pseudarthrosis in the multivariate analysis.

CONCLUSION

Overall pseudarthrosis rates were similar between small rods and transitional constructs. There was higher complications rate, blood loss, and operating time associated with transitional constructs. Pseudarthrosis risk factors at the cervicothoracic junction include tobacco use, corpectomy, lack of an anterior construct, and longer constructs.

LEVEL OF EVIDENCE

3.

Surgical planning and neurological outcome after anterior approach to remove a disc herniation at the C7-T1 level in 19 patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The purpose of this study was to report the neurological presentation, outcome and surgical planning in a series of patients with a symptomatic single-level C7-T1 disc herniation who underwent anterior surgical discectomy and fusion.

SUMMARY OF BACKGROUND DATA

Disc herniations at C7-T1 are uncommon, and there are few large series in the literature describing anterior treatment of such herniations.

METHODS

We performed a retrospective study of patients who underwent surgery for a C7-T1 disc herniation and reviewed the medical records, operative reports, and imaging studies. The surgeons' view line was drawn and its relation to the manubrium and the great vessels was determined on T1 sagittal magnetic resonance imaging. The location of the herniated disc in the spinal canal was determined using a T2 axial magnetic resonance imaging and classified as central, foraminal, and central/foraminal. Loss of muscle strength was evaluated preoperatively and at the last follow-up according to the classification of the Medical Research Council. The disc space was approached anteriorly by a standard cervical supramanubrial Smith-Robinson approach.

RESULTS

We identified 19 patients who had undergone C7-T1 discectomy and fusion. The mean age of the sample was 54.26 ± 8.65 years. There was a higher proportion of male patients (57.9%, 11/19). The clinical presentation was predominantly motor deficit in 15/19 cases (78.9%) in intrinsic hand muscles, and usually improved after surgery. The mean follow-up period was 27.05 ± 15.10 months. All the patients underwent an anterior cervical supramanubrial approach with microdiscectomy and fusion. Anterior cervical plate fixation was used in 9/19 cases (47.3%). In the rest of the cases, a stand-alone intervertebral device was placed.

CONCLUSION

An anterior cervical supramanubrial approach was easily accomplished in all patients. Motor deficit was the most common surgical indication.

LEVEL OF EVIDENCE

4.

Anterior approach to the cervicothoracic junction: proposed indication for manubriotomy based on preoperative computed tomography findings

Object

The purpose of this study was to present straightforward preoperative methods to define the need for manubriotomy in the anterior surgical approach to the cervicothoracic junction.

Methods

Preoperative MR imaging and CT scanning studies were performed in all patients. The CT images with sagittal reconstructions including the manubrium were done to apply the so-called surgeons' view line. This line is parallel to the inferior plateau of the superior healthy vertebrae or the vertebrae above the herniated intervertebral disc, and the decision concerning the need for manubriotomy depends on the correlation between this line and the manubrium.

Results

Preoperative planning of the need for manubriotomy was correct in all cases. Manubriotomy was never performed in C-7 corpectomy or C7–T1 discectomy cases; nevertheless, manubriotomy was needed in half of the cases when the T-1 corpectomy was the lowest level to be resected (8 cases), and in 4 cases the lowest level to be approached was T-2. The mean surgical time, bleeding volume, postoperative pain intensity, and length of hospital stay were less in the cervicotomy than in the manubriotomy group.

Conclusions

By using the surgeons' view line and its correlation with the manubrium, the need for manubriotomy can be predicted without compromising decompression and reconstruction. The statistical differences observed in the surgical variables between the manubriotomy and cervicotomy cases justified the use of preoperative evaluation of the need for manubriotomy as an aid to surgical planning and to give the patient and family realistic expectations about the surgery.

Spine surgery in neurological lesions of the cervicothoracic junction: multicentric experience on 33 consecutive cases

Surgical treatment of the cervico-thoracic junction (CTJ) in the spine require special evaluation due to the anatomical and biomechanical characteristics of this spinal section. The transitional zone between the mobile cervical and the relatively rigid thoracic spine can be the site of serious unstable traumas or neoplastic lesions. Frequently, injury is associated with neurological impairment due to the small caliber of the spinal canal and/or spinal cord vascular insufficiency. The authors considered 33 neurologic lesions of the CTJ (21 traumas, 10 tumors, 2 infections) treated by means of decompression, fixation, and fusion by different type of instrumentation. Surgical procedure was posterior in 26 cases, anterior in 1 and combined in 6. Major general complications were not found in patients undergoing anterior approach. Biomechanical failure was found in two patients operated by T1 body replacement and C7-T2 anterior plate. Serious cardio-respiratory complications were related to 2 polytrauma patients who underwent posterior surgery. Follow-up evaluation showed spinal stability and fusion in 88% of cases, improvement of the neurological deficits in 42% (19% improved to ASIA E), no or only occasional pain in 75% of patients. In the experience, recovery of spinal realignment and stability is essential to avoid disability due to back pain in trauma patients. In spinal tumors, back pain was related to local recurrence. Neurological outcomes can be unsatisfactory due to the initial serious impairment. There is no type of instrumentation more effective than other. In each single lesion, the most suitable type of instrumentation should be employed, considering morphology, biomechanics, and familiarity of the spinal surgeon with different implants and constructs. Therefore, we prefer to use posterior cervicothoracic fixation in T1 lesions with involvement of the vertebral body and subsequently replace the body with cage without anterior stabilization.

Surgical management of two- versus three-column injuries of the cervicothoracic junction: biomechanical comparison of translaminar screw and pedicle screw fixation using a cadaveric model

STUDY DESIGN

An in vitro cadaveric biomechanical study.

OBJECTIVE

To determine the stability of translaminar screws compared to pedicle screws at T1-T2 for constructs bridging the cervicothoracic junction.

SUMMARY OF BACKGROUND DATA

Instrumented fixation of the cervicothoracic junction is challenging both biomechanically, due to the transition from the mobile cervical to the rigid thoracic spine, and technically, due to the anatomic constraints of the T1-T2 pedicles. For these reasons, an alternate fixation technique at T1-T2 that combines ease of screw insertion and a favorable safety profile with biomechanical stability would be clinically beneficial.

METHODS

A 6-degree of freedom spine simulator was used to test multidirectional flexibility in 8 human cadaveric specimens. Flexion, extension, lateral bending, and axial rotation were tested in the intact condition, followed by destabilization via a simulated 2-column injury at C7-T1. Specimens were reconstructed using C5-C6 lateral mass screws and either translaminar or pedicle screws placed at T1, followed by caudal extension to T2. A 3-column injury at C7-T1 was then performed and specimens were tested using a posterior only approach with either translaminar or pedicle screws placed at T1 and T1-T2. Finally, anterior fixation at C7-T1 was added and multidirectional flexibility testing performed as previously described.

RESULTS

Following a 2-column injury at C7-T1, there were no significant differences in segmental flexibility at C7-T1 between translaminar and pedicle screw fixation when placed at T1-T2 (P>0.05). For a 3-column injury treated posteriorly, translaminar screws at T1-T2 provided increased flexibility compared to pedicle screws in flexion/extension (P<0.05). There were no differences in segmental flexibility at C7-T1 between the 2 techniques following the addition of anterior fixation (P>0.05).

CONCLUSION

Translaminar screws in the upper thoracic spine offer similar stability to pedicle screw fixation for constructs bridging the cervicothoracic junction. Small differences in range of motion must be weighed clinically against the potential benefits of translaminar screw insertion at T1-T2.

The use of pedicle screw-rod system for the posterior fixation in cervico-thoracic junction

OBJECTIVE

In cervico-thoracic junction (CTJ), the use of strong fixation device such as pedicle screw-rod system is often required. Purpose of this study is to analyze the anatomical features of C7 and T1 pedicles related to screw insertion and to evaluate the safety of pedicle screw insertion at these levels.

METHODS

Nineteen patients underwent posterior CTJ fixation with C7 and/or T1 included in fixation levels. Seventeen patients had tumorous conditions and two with post-laminectomy kyphosis. The anatomical features were analyzed for C7 and T1 pedicles in 19 patients using computerized tomography (CT). Pedicle screw and rod fixation system was used in 16 patients. Pedicle violation by screws was evaluated with postoperative CT scan.

RESULTS

The mean values of the width, height, stable depth, safety angle, transverse angle, and sagittal angle of C7 pedicles were 6.9 +/- 1.34 mm, 8.23 +/- 1.18 mm, 30.93 +/- 4.65 mm, 26.42 +/- 7.91 degrees, 25.9 +/- 4.83 degrees, and 10.6 +/- 3.39 degrees. At T1 pedicles, anatomic parameters were similar to those of C7. The pedicle violation revealed that 64.1% showed grade I violation and 35.9% showed grade II violation, overall. As for C7 pedicle screw insertion, grade I was 61.5% and grade II 38.5%. At T1 level, grade I was 65.0% and grade II 35.0%. There was no significant difference in violation rate between the whole group, C7, and T1 group.

CONCLUSION

C7 pedicles can withstand pedicle screw insertion. C7 pedicle and T1 pedicle are anatomically very similar. With the use of adequate fluoroscopic oblique view, pedicle screw can be safely inserted at C7 and T1 levels.

A computed tomography-based feasibility study of translaminar screw fixation in the upper thoracic spine

OBJECT

Translaminar screws (TLSs) offer an alternative to pedicle screw (PS) fixation in the upper thoracic spine. Although cadaveric studies have described the anatomy of the laminae and pedicles at T1-2, CT imaging is the modality of choice for presurgical planning. In this study, the goal was to determine the diameter, maximal screw length, and optimal screw trajectory for TLS placement at T1-2, and to compare this information to PS placement in the upper thoracic spine as determined by CT evaluation.

METHODS

One hundred patients (50 men and 50 women), whose average age was 41.7 +/- 19.6 years, were selected by retrospective review of a trauma registry database over a 6-month period. Patients were included in the study if they were over the age of 18, had standardized axial bone-window CT imaging at T1-2, and had no evidence of spinal trauma. For each lamina and pedicle, width (outer cortical and cancellous), maximal screw length, and optimal screw trajectory were measured using eFilm Lite software. Statistical analysis was performed using the Student t-test.

RESULTS

The T-1 lamina was estimated to accommodate, on average, a 5.8-mm longer screw than the T-2 lamina (p < 0.001). At T-1, the maximal TLS length was similar to PS length (TLS: 33.4 +/- 3.6 mm, PS: 33.9 +/- 3.3 mm [p = 0.148]), whereas at T-2, the maximal PS length was significantly greater than the TLS length (TLS: 27.6 +/- 3.1 mm, PS: 35.3 +/- 3.5 mm [p < 0.001]). When the lamina outer cortical and cancellous width was compared between T-1 and T-2, the lamina at T-2 was, on average, 0.3 mm wider than at T-1 (p = 0.007 and p = 0.003, respectively). In comparison with the corresponding pedicle, the mean outer cortical pedicle width at T-1 was wider than the lamina by an average of 1.0 mm (lamina: 6.6 +/- 1.1 mm, pedicle: 7.6 +/- 1.3 mm [p < 0.001]). At T-2, however, outer cortical lamina width was wider than the corresponding pedicle by an average of 0.6 mm (lamina: 6.9 +/- 1.1 mm, pedicle: 6.3 +/- 1.2 mm [p < 0.001]). At T-1, 97.5% of laminae measured could accept a 4.0-mm screw with 1.0 mm of clearance, compared with 99.5% of T-1 pedicles; whereas at T-2, 99% of laminae met this requirement, compared with 94.5% of pedicles. The ideal screw trajectory was also measured (T-1: 49.2 +/- 3.7 degrees for TLS and 32.8 +/- 3.8 degrees for PS; T-2: 51.1 +/- 3.5 degrees for TLS and 20.5 +/- 4.4 degrees for PS).

CONCLUSIONS

Based on CT evaluation, there are no anatomical limitations to the placement of TLSs compared with PSs at T1-2. Differences were noted, however, in lamina length and width between T-1 and T-2 that must be considered when placing TLS at these levels.

Trans-upper-sternal approach to the cervicothoracic junction

From August 1999 to February 2006, 11 patients with cervicothoracic lesions (eight males, three females; age range, 17-77 years) were surgically treated using the trans-upper-sternal approach. Combined cervicothoracic incision and upper sternotomy facilitated exposure for tumor resection, partial or subtotal removal of the involved vertebrae, and spinal cord decompression. The spinal column then was stabilized. Neurologic status was assessed using the Frankel classification. Followup for a minimum of 10 months (mean, 31 months; range, 10-56 months) revealed one patient had a chyle leak (50 mL) 1 day after surgery, which resolved after 2 days of drainage. One patient had a transient vocal cord paresis, which recovered within 3 months of surgery. All the patients had improved neurologic function. No nonunions or instrument-related complications developed. Stability of the vertebral column was maintained during followup in all patients. The trans-upper-sternal approach can provide excellent exposure for reconstruction of the cervicothoracic junction. Special care must be taken to avoid injury to the recurrent laryngeal nerve and the thoracic duct.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Useful C8 and T1 function seen immediately after a complete cervical spinal cord injury: report of 2 cases

BACKGROUND

Because of the rarity of cervicothoracic spine injuries, detailed reports on the neurologic examination after complete cord injuries are scarce. A few retrospective case series scantily documented the intrinsic hand function after C7-T1 complete cord injuries. A complete cervical cord injury with useful C8 and T1 motor function present immediately after the injury has not been reported to date.

CASE DESCRIPTION

Functional C8 and T1 motor strength at the time of the initial neurologic examination was seen in 2 cases in which a complete C7-T1 injury resulted in paraplegia. Serial neurologic examinations were performed to document useful C8 and T1 motor function and maintenance of the neurologic status after surgical treatment.

CONCLUSIONS

Patients can present with useful lower cervical root function (C8 and T1) when first seen at admission after a complete cervical cord injury. Careful neurologic examination must be performed at admission in patients with lower cervical spine injuries because useful intrinsic hand function can be present and must not be overlooked.

Anterior approach to the cervicothoracic junction: case series and literature review

OBJECTIVES: the authors report their experience with the anterior approach to the cervicothoracic junction at C7 to T4 vertebral bodies, how the radiological investigation was performed in order to define the need for manubriotomy, how was the surgical pitfalls and the clinical evaluation. METHODS: prospective cohort study with 14 patients who underwent an anterior approach to the cervicothoracic surgery during the period of January 1996 to January 2009. The patients underwent radiographic evaluation with computed tomography and magnetic resonance before surgery in order to identify when the manubriotomy was necessary. The surgery was usually performed from the left side through an anterior Smith-Robinson approach and manubriotomy when necessary. Mesh and cervical plate system were used for stabilization when corpectomy was performed. Nevertheless, in the cases with discal herniation C7-T1, the reconstruction was done with PEEK and cervical plate system. RESULTS: the mean age was 63 years old (range, 30-77 years) and seven of the patients were men. The majority of cases had metastatic disease (n=8) or disc herniation (n=4). There were two complications related to the surgical procedures: one patient with dysphonia caused by a local hematoma and other one with lung infection. The mean surgical time, bleeding volume, pain intensity, medication intake and length of hospital stay were lower in the cases in which manubriotomy was not necessary. CONCLUSIONS: the anterior approach to the cervicothoracic junction is effective and presents low morbidity rate. In cases of injuries involving the C7 vertebral body and C7-T1 intervertebral disc herniation, a transcervical approach without the manubriotomy was indicated; when a T1 and/or T2 corpectomy was necessary, the transmanubrial approach usually was necessary in order to provide a good working space to perform a corpectomy and reconstruction. Performing manubriotomy increases surgical time, bleeding, pain intensity, analgesic drugs intake and the length of hospital stay.

Surgery in the cervicothoracic junction with an anterior low suprasternal approach alone or combined with manubriotomy and sternotomy: an approach selection method based on the cervicothoracic angle

Object

The authors propose an easy MR imaging method to measure and categorize individual anatomical variations within the cervicothoracic junction (CTJ). Furthermore, they propose guidelines for selection of the appropriate approach based on this new categorization system.

Methods

In the midsagittal section of the cervicothoracic MR imaging studies obtained in 95 Chinese patients, a triangle was drawn among 3 points: the suprasternal notch (SSN), the midpoint of the anterior border of the C7/T1 intervertebral disc, and the corresponding anterior border in the CTJ at the level of the SSN. The angle above the SSN was specified as the cervicothoracic angle (CTA). The spatial position between the brachiocephalic vein (BCV), the aortic arch, and the CTA was also measured. Based on these measurements involving the CTA, 3 different patient-specific categorizations are proposed to assist surgeons with selection of the appropriate anterior approach to the CTJ. Three categories of operative approach based on whether the most caudal part of the lesion site was above, within, or below the area of the CTA were classified. The patients were divided into long- or short-necked groups based on whether their own CTA was greater than (long necked) or less than (short necked) the average CTA. Finally, a left BCV was called superiorly located when it coursed above the manubrium. The method was evaluated in 21 patients with spinal bone tumors in the CTJ to illustrate the measurement of both the CTA and the great vessels, and corresponding approach selections.

Results

In this series of 95 patients, the most common vertebra above the SSN was T-3, especially the upper one-third of T-3. The mean CTA was 47.64°. The left BCV was superior to the manubrium in 21.1% of the 95 cases, and 93.6% of the left BCVs were at the T-2 and T-3 levels. Type A and most Type B lesions could be addressed via a low suprasternal approach, or this approach combined with manubriotomy, if necessary. Type C lesions falling below the CTA will need alternative exposure techniques, including manubriotomy, sternotomy, lateral extracavitary, or thoracotomy. The spinal levels that could be exposed in the long-necked CTJ group were always 1 or 2 vertebral levels lower than those in the short-necked CTJ group during the anterior low suprasternal approach without the manubriotomy.

Conclusions

Imaging of the thoracic manubrium should be routinely included on MR imaging studies obtained in the CTJ. It is important for the surgeon to understand the pertinent anatomy of the individual patients and to determine the feasible surgical approaches after evaluating the CTA and vascular factors preoperatively. An anterior low suprasternal approach, or this approach combined with manubriotomy, is applicable in most of the cases in the CTJ. It should be cautioned that preoperatively unrecognized variations of the left BCV above the SSN might result in potential intraoperative trauma during an anterior approach.

Tratamento cirúrgico das doenças da transição cervicotorácica

OBJETIVO: avaliar o resultado do tratamento cirúrgico de pacientes portadores de doenças na transição cervicotorácica da coluna vertebral. MÉTODOS: foram avaliados, retrospectivamente, 20 pacientes: nove (45%) apresentavam lesões traumáticas, sete (35%) lesões neoplásicas e quatro (20%) doenças degenerativas. No grupo de pacientes com lesões traumáticas, foi realizada fixação posterior em cinco deles (55,5%), fixação anterior em um (11,1%) e abordagem combinada (anterior e posterior) em três (33,3%). Dos sete pacientes com lesões tumorais, quatro (57,1%) foram submetidos ao tratamento cirúrgico pela abordagem combinada e três (42,8%) pela abordagem posterior isolada. No grupo de pacientes com doenças degenerativas da coluna vertebral, três (75%) foram tratados pela abordagem posterior e um (25%) de forma combinada. Todos os pacientes foram avaliados por meio de parâmetros clínicos (dor e déficit neurológico), radiológicos (manutenção da redução, soltura ou quebra dos implantes) e funcionais (SF-36, escala de dor e trabalho de Denis). RESULTADOS: os 20 pacientes foram seguidos por um período que variou de seis meses a 11 anos (média de 44,6 meses ± 29,02). Dos 13 pacientes que apresentavam déficit neurológico, oito apresentaram melhora do nível na escala de Frankel (61,5%) e cinco pacientes (38,4%) permaneceram com o quadro inalterado. Como complicações um paciente (5%) apresentou soltura do implante e quatro pacientes evoluíram com infecção pós-operatória (20%). Segundo as escalas de dor e trabalho de Denis, 80% dos pacientes apresentavam pouca ou nenhuma dor (P1 e P2) e 70% dos pacientes tinham retornado ao trabalho (W1, W2 e W3). Os pacientes que não apresentavam déficit neurológico (Frankel E) obtiveram escores mais altos de qualidade de vida pelo questionário SF-36, quando comparados aos escores dos pacientes que mantinham alterações neurológicas (Frankel A-D). CONCLUSÃO: o tratamento das doenças da transição cervicotorácica da coluna vertebral apresenta detalhes adicionais aos demais segmentos da coluna vertebral. Na vigência de tratamento cirúrgico, existem pontos a serem respeitados como a anatomia relacionada ao acesso cirúrgico, as características anatômicas peculiares das vértebras e a biomecânica singular desse segmento da coluna vertebral.

Posterior stabilization strategies following resection of cervicothoracic junction tumors: review of 90 consecutive cases

Object

In this retrospective analysis the authors describe the assessment and outcomes of 90 patients who underwent placement of posterior instrumentation at the cervicothoracic junction following the resection of a primary or metastatic tumor during a 10-year period.

Methods

All patients underwent a posterolateral laminectomy including uni- or bilateral facetectomy, and 44 patients additionally required vertebral body resection and reconstruction. In patients who underwent C-6 or C-7 decompression, the posterior instrumentation strategies changed from the use of lateral mass plate systems (LMPSs) to lateral mass screw/rod systems (LMSRSs). Similarly, for T1–3 tumor decompression, the strategy shifted from sublaminar hook/rod systems (SHRSs) to the use of pedicle screw systems (PSSs) in which the surgeon used either a 6.25-mm rod or dual-diameter rods with or without a connector.

Results

The overall surgical complication rate was 19% including fixation failure in 11 patients (12%), 6 of whom required reoperation. Fixation failure rates for cervical decompression decreased from 2 (29%) of 7 patients in the LMPS group to 0 (0%) of 8 in the LMSRS group (p = 0.2). The fixation failure rates for thoracic decompression were 7 (15%) of 48 patients in the SHRS group, and there was a decrease to 2 (7%) of 27 in the PSS group (p = 0.48). Neurological and functional outcomes including American Spinal Injury Association, Eastern Cooperative Oncology Group, and Medical Research Council muscle strength and pain scores remained stable or improved in 94, 96, 100, and 96% of patients, respectively.

Conclusions

Current posterior instrumentation strategies involving LMSRSs and PSSs provide excellent and safe stabilization of the cervicothoracic junction following resection of primary or metastatic tumors.

Anterior surgical management of the cervicothoracic junction lesions at T1 and T2 vertebral bodies

Lesions of the cervicothoracic junction have a high propensity for causing instability and present unique challenges in the surgical treatment. Several surgical approaches to this region have been described in the literature. We report our experience in the surgical treatment of six patients with unstable lesions involving the cervicothoracic junction at T1 and T2 vertebral bodies. The patients underwent an anterior left Smith-Robinson approach and manubriotomy. Mesh and cervical plate system were used for stabilization and reconstruction of the region. No complication related to the surgical procedure was observed. In our experience, in injuries involving the T1 and T2 vertebral bodies, the transmanubrial approach offers good working room to remove the lesions and anterior reconstruction.

The cervicothoracic junction

The cervicothoracic junction (CTJ) represents a unique region in the spine because of its biomechanical properties. It is predisposed to various traumatic injuries, tumor, and iatrogenic instability. It is also a difficult region to access anteriorly because of the vital structures ventral to the CTJ. The development of new surgical techniques and new instrumentation has allowed better access and fixation to the CTJ.

A Comparative Biomechanical Analysis of Spinal Instability and Instrumentation of the Cervicothoracic Junction

OBJECTIVE

Stabilization of the cervicothoracic junction is challenging but commonly required in patients with traumatic, neoplastic, congenital, and postlaminectomy conditions. Although extensive research has been performed on stabilization of the cervical spine, there remains a paucity of published data on instrumentation at the cervicothoracic junction. Using 2-column, 3-column, and corpectomy instability models, a biomechanical analysis was performed on the effects of increasing the number of posterior segmental fixation points and/or anterior column reconstruction at the cervicothoracic junction.

METHODS

Multidirectional flexibility testing was performed utilizing a 6-degree-of-freedom spine simulator and 7 fresh-frozen human cadaveric spines (occiput-T6). After intact spine analysis, each specimen was destabilized and reconstructed as follows: (1) C7/T1 2-column injury with posterior instrumentation; (2) C7/T1 3-column injury with posterior instrumentation; (3) C7/T1 3-column injury with anterior interbody cage/plate and posterior instrumentation; and (4) C7/T1 3-column injury plus C7 corpectomy with anterior cage/plate and posterior instrumentation. All reconstruction groups were tested with posterior instrumentation (screws connected by dual-diameter rods) from C5-T1, C5-T2, and C5-T3.

RESULTS

For 2-column injuries, there were no statistically significant differences in flexibility (P>0.05), although there was a trend toward reduced flexibility with increasing levels of thoracic fixation. For 3-column injuries, posterior fixation alone resulted in excessive flexibility in flexion/extension even with instrumentation to T3 (P<0.05). With the addition of anterior column instrumentation, there were no observed differences in flexion/extension and lateral bending. For axial rotation, instrumentation to T1 alone demonstrated increased motion relative to the intact spine (P<0.05). The 3-column injury with corpectomy model demonstrated similar flexibility properties to the 3-column injury model.

CONCLUSIONS

With 3-column instability posterior segmental fixation alone from C5-T3 was inadequate, and the addition of anterior instrumentation restored flexibility to the intact condition. There was a strong trend toward reduced flexibility with increasing levels of thoracic fixation in all instability models.

Role of intraoperative Iso-C based navigation in challenging spine trauma

BACKGROUND

Pedicle screw fixation is the most preferred method of stabilizing unstable spinal fractures. Pedicle screw placement may be difficult in presence of fractured posterior elements, deformed spine, gross instability and spinal pathology. Challenging spine-fracture fixation is defined as the presence of one or more of the following: 1) obscured topographical landmarks as in ankylosing spondylitis, 2) fractures in occipitocervical or cervicothoracic regions and 3) preexisting altered spinal alignment. We report a series of pedicle screw insertion with guidance of navigation in difficult fixation problems..

MATERIALS AND METHODS

Fourteen patients [hangman's fracture (n=3), odontoid fracture (n=4), C1C2 fracture (n=1) and spinal fracture with coexistent ankylosing spondylitis (n=6)] underwent posterior stabilization. Intraoperatively after surgical exposure, images were acquired by Iso-C 3D C-arm and transferred to navigation system. Instrumentation was performed with navigational assistance. Postoperatively, placements of pedicle screws were evaluated with radiographs and CT scan.

RESULTS

Sixty-seven pedicle screws (cervical, n=33; thoracic, n=6; lumbar, n=26; sacral n=2) and 15 lateral mass screws were inserted with navigation guidance. The average time of image data acquisition by Iso-C 3D C-arm and its transfer to workstation was 4 minutes (range, 2-6 minutes). Postoperative CT scan revealed ideal placement of screws in 63 pedicles (94%), grade 1 cortical breaches (<2 mm) in 3 pedicles (4.5%) and grade 2 cortical breach (2-4 mm) in one pedicle (1.5%). There were no neurovascular complications. Deep infection was encountered in one case, which settled with debridement.

CONCLUSIONS

Intraoperative Iso-C 3D C-arm based navigation is a useful adjunct while stabilizing challenging spinal trauma, rendering feasibility, accuracy and safety of pedicle screw placement even in difficult situations.

Translaminar screw fixation in the upper thoracic spine

Object

The use of pedicle screws (PSs) for instrument-assisted fusion in the cervical and thoracic spine has increased in recent years, allowing smaller constructs with improved biomechanical stability and repositioning possibilities. In the smaller pedicles of the upper thoracic spine, the placement of PSs can be challenging and may increase the risk of damage to neural structures. As an alternative to PSs, translaminar screws can provide spinal stability, and they may be used when pedicular anatomy precludes successful placement of PSs. The authors describe the technique of translaminar screw placement in the T-1 and T-2 vertebrae.

Methods

Seven patients underwent cervicothoracic fusion to treat trauma, neoplasm, or degenerative disease. Nineteen translaminar screws were placed, 13 at T-1 and six at T-2. A single asymptomatic T-2 screw violated the ventral laminar cortex and was removed.

The mean clinical and radiographic follow up exceeded 14 months, at which time there were no cases of screw pull-out, screw fracture, or progressive kyphotic deformity.

Conclusions

Rigid fixation with translaminar screws offers an attractive alternative to PS fixation, allowing the creation of sound spinal constructs and minimizing potential neurological morbidity. Their use requires intact posterior elements, and care should be taken to avoid violation of the ventral laminar wall.

A perspective for the selection of surgical approaches in patients with upper thoracic and cervicothoracic junction instabilities

OBJECTIVE

To reach the upper thoracic vertebrae, a number of extensive approaches have been proposed. The purpose of this study is to provide a clear perspective for the selection of surgical approaches in patients who undergo vertebral body resection, reconstruction, and stabilization for upper thoracic and cervicothoracic junction instabilities.

METHODS

Seventeen patients with upper thoracic or cervicothoracic junction (C7-T6) instability underwent surgery between January 1999 and May 2004. All patients presented with pain and/or neurological deficits. The causes of instabilities were 10 traumas and 7 pathological fractures. The approach chosen was primarily dictated by 3 factors including (1) type of injury, (2) level of lesion, and (3) time of admission. Ventral surgical approach was performed to all pathological and traumatic fractures causing anterior spinal cord compression. Level of lesion determined the selection of the type of ventral surgical approach, namely, supramanubrial, transmanubrial, or lateral transthoracic. On the other hand, combined (anterior and posterior) approach was performed to all late admitted trauma patients.

RESULTS

Twelve anterior, 2 combined (anterior and posterior), and 3 posterior approaches were performed in this study. Anterior approaches included 3 transmanubrial, 5 upper lateral transthoracic, and 4 supramanubrial cervical dissection procedures for decompression, fusion, and plate-screw fixation depending on the levels of the lesion. The mean follow-up period was 18 months, ranging from 10 to 58 months. Nonunion or instrument-related complications were not observed. The postoperative neurological conditions were statistically significantly better than the preoperative ones (P = .003).

CONCLUSION

Consideration of the type of injury, level of lesion, and time of admission can provide a perspective for the selection of side of surgical approach for this transitional part of the spinal column. This study also suggests that supramanubrial cervical approach achieves sufficient exposure up to T2, transmanubrial approach for T3, and lateral transthoracic approach below T3.

Fractures and Dislocations of the Cervicothoracic Junction

Presented is a retrospective review of case notes and all available imaging studies in seven patients with acute fractures-dislocations of the cervicothoracic junction. Imaging studies included radiographs (five cases), computed tomography (six cases), and magnetic resonance imaging (seven cases). The study group consisted of five men and two women with mean age at presentation of 43.6 years (range 25-69 years). Four patients had been in road traffic accidents, whereas three patients had had falls. Three patients sustained complete neurologic deficits with no recovery, whereas the remaining four had no abnormal neurology or mild deficit at presentation and were normal at final follow-up. The injury was missed initially in three cases. The commonest injury pattern was traumatic spondylolisthesis of C7 on T1 with multilevel neural arch fractures, resulting in increased anteroposterior canal dimensions (four cases). Bilateral pars fractures of C7 and pure facet dislocation were seen in one case each. Neurologic deficit was related to the degree of anterior displacement of C7 on T1. Fracture-dislocation at the cervicothoracic junction is a rare injury with a variation of injury patterns and neurologic outcome.

Surgical treatment of tumors involving the cervicothoracic junction

OBJECT

Tumors involving the cervicothoracic junction can have a high propensity for causing instability, with kyphosis and spinal cord compression resulting. Treatment with decompression only can lead to further instability and worsening neurological status. In this article, the authors review their surgical experience in the treatment of 19 patients with tumors involving the cervicothoracic junction. The various approaches and instrumentation techniques involved in decompression and stabilization of the cervicothoracic junction are also reviewed.

METHODS

Aggressive instrumentation-augmented fusion after decompression of the cervicothoracic region can provide for immediate stabilization and early rehabilitation. Recent development of new hardware such as dual-diameter transition rods, polyaxial screws, and interlocking devices have enhanced the ability to fashion a strong construct for stabilization of the cervicothoracic junction.

CONCLUSIONS

Familiarity with complex instrumentation techniques and various surgical approaches to the cervicothoracic junction will be required for effective treatment of tumors causing instability of this region.