Cervical Kyphosis

Pedicle subtraction metallectomy with complex posterior reconstruction for fixed cervicothoracic kyphosis: illustrative case

BACKGROUND

Iatrogenic cervical deformity is a devastating complication that can result from a well-intended operation but a poor understanding of the individual biomechanics of a patient's spine. Patient factors, such as bone fragility, high T1 slope, and undiagnosed myopathies often play a role in perpetuating a deformity despite an otherwise successful surgery. This imbalance can lead to significant morbidity and a decreased quality of life.

OBSERVATIONS

A 55-year-old male presented to the authors' clinic with a chin-to-chest deformity and cervical myelopathy. He previously had an anterior C2-T2 fixation and a posterior C1-T6 instrumented fusion. He subsequently developed screw pullout at multiple levels, so the original surgeon removed all of the posterior hardware. The T1 cage (original corpectomy) severely subsided into the body of T2, generating an angular kyphosis that eventually developed a rigid osseous circumferential union at the cervicothoracic junction with severe cord compression. An anterior approach was not feasible; therefore, a 3-column osteotomy/fusion in the upper thoracic spine was planned whereby 1 of the T2 screws would need to be removed from a posterior approach for the reduction to take place.

LESSONS

This case highlights the devastating effect of a hardware complication leading to a fixed cervical spine deformity and the complex decision making involved to safely correct the challenging deformity and restore function.

Patient-Reported Outcomes Following Anterior and Posterior Surgical Approaches for Multilevel Cervical Myelopathy

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

To compare health-related quality of life (HRQoL) outcomes between approach techniques for the treatment of multilevel degenerative cervical myelopathy (DCM).

SUMMARY OF BACKGROUND DATA

Both anterior and posterior approaches for the surgical treatment of cervical myelopathy are successful techniques in the treatment of myelopathy. However, the optimal treatment has yet to be determined, especially for multilevel disease, as the different approaches have separate complication profiles and potentially different impacts on HRQoL metrics.

MATERIALS AND METHODS

Retrospective review of a prospectively managed single institution database of patient-reported outcome measures after 3 and 4-level anterior cervical discectomy and fusion (ACDF) and posterior cervical decompression and fusion (PCDF) for DCM. The electronic medical record was reviewed for patient baseline characteristics and surgical outcomes whereas preoperative radiographs were analyzed for baseline cervical lordosis and sagittal balance. Bivariate and multivariate statistical analyses were performed to compare the two groups.

RESULTS

We identified 153 patients treated by ACDF and 43 patients treated by PCDF. Patients in the ACDF cohort were younger (60.1 ± 9.8 vs . 65.8 ± 6.9 yr; P < 0.001), had a lower overall comorbidity burden (Charlson Comorbidity Index: 2.25 ± 1.61 vs . 3.07 ± 1.64; P = 0.002), and were more likely to have a 3-level fusion (79.7% vs . 30.2%; P < 0.001), myeloradiculopathy (42.5% vs . 23.3%; P = 0.034), and cervical kyphosis (25.7% vs . 7.69%; P = 0.027). Patients undergoing an ACDF had significantly more improvement in their neck disability index after surgery (-14.28 vs . -3.02; P = 0.001), and this relationship was maintained on multivariate analysis with PCDF being independently associated with a worse neck disability index (+8.83; P = 0.025). Patients undergoing an ACDF also experienced more improvement in visual analog score neck pain after surgery (-2.94 vs . -1.47; P = 0.025) by bivariate analysis.

CONCLUSIONS

Our data suggest that patients undergoing an ACDF or PCDF for multilevel DCM have similar outcomes after surgery.

Posterior Preventive Foraminotomy before Laminectomy Combined with Pedicle Screw Fixation May Decrease the Incidence of C5 Palsy in Complex Cervical Spine Surgery in Patients with Severe Myeloradiculopathy

C5 palsy is a frequent sequela of cervical decompression surgeries for cervical myeloradiculopathy. Although many researchers have suggested various risk factors, such as cord shifting and the correction of lordotic angles, the tethering of the C5 root beneath the narrow foramen is an independent risk factor for C5 palsy. In this study, we tried to investigate different techniques for foramen decompression with posterior cervical fusion and assess the incidence of C5 palsy with each technique depending on the order of foraminal decompression. A combined 540° approach with LMS and uncovertebrectomy was used in group 1. Group 2 combined a 540° approach with pedicle screws and posterior foraminotomy, while posterior approach only with pedicle screws and foraminotomy was used in group 3. For groups 2 and 3, prophylactic posterior foraminotomy was performed before laminectomy. Motor manual testing to assess C5 palsy, the Neck Disability Index (NDI) and the Japanese Orthopedic Association (JOA) scores were determined before and after surgery. Simple radiographs, MRI and CT scans, were obtained to assess radiologic parameters preoperatively and postoperatively. A total of 362 patients were enrolled in this study: 208 in group 1, 72 in group 2, and 82 in group 3. The mean age was 63.2, 65.5, and 66.6 years in groups 1, 2, and 3, respectively. The median for fused levels was 4 for the three groups. There was no significant difference between groups regarding the number of fused levels. Weight, height, comorbidities, and diagnosis were not significantly different between groups. Preoperative JOA scores were similar between groups (p = 0.256), whereas the preoperative NDI score was significantly higher in group 3 than in group 2 (p = 0.040). Mean JOA score at 12-month follow-up was 15.5 ± 1.89, 16.1 ± 1.48, and 16.1 ± 1.48 for groups 1, 2, and 3, respectively; it was higher in group 3 compared with group 1 (p = 0.008) and in group 2 compared with group 1 (p = 0.024). NDI score at 12 months was 13, 12, and 13 in groups 1, 2, and 3, respectively; it was significantly better in group 3 than in group 1 (p = 0.040), but there were no other significant differences between groups. The incidence of C5 palsy was significantly lower in posterior foraminotomy groups with pedicle screws (groups 2 and 3) than in LMS with uncovertebrectomy (group 1) (p < 0.001). Thus, preventive expansive foraminotomy before decompressive laminectomy is able to significantly decrease the root tethering by stenotic lesion, and subsequently, decrease the incidence of C5 palsy associated with posterior only or combined posterior and anterior cervical fusion surgeries. Additionally, such expansive foraminotomy might be appropriate with pedicle screw insertion based on biomechanical considerations.

Patient-reported outcome measures in spine surgery: A systematic review

Background

Steadily increasing expenditure in the United States health-care system has led to a shift toward a value-based model that focuses on quality of care and cost-effectiveness. Operations involving the spine rank among some of the most common and expensive procedures performed in operating rooms nationwide. Patient-reported outcomes measures (PROMs) are a useful tool for reporting levels of outcome and analyzing patient recovery but are both under-utilized and nonstandardized in spine surgery.

Methods

We conducted a systematic review of the literature using the PubMed database, focusing on the most commonly utilized PROMs for spine disease as well as spinal deformity. The benefits and drawbacks of these PROMs were then summarized and compared.

Results

Spine-specific PROMs were based on the class of disease. The most frequently utilized PROMs were the Neck Disability Index and the modified Japanese Orthopaedic Association scale; the Oswestry Disability Index and the Roland-Morris Disability Questionnaire; and the Scoliosis Research Society 22-item questionnaire (SRS-22) for cervicothoracic spine disease, lumbar spine disease, and spinal deformity, respectively.

Conclusion

We found limited, though effective, use of PROMs targeting specific classes of disease within spine surgery. Therefore, we advocate for increased use of PROMs in spine surgery, in both the research and clinical settings. PROM usage can help physicians assess subjective outcomes in standard ways that can be compared across patients and institutions, more uniquely tailor treatment to individual patients, and engage patients in their own medical care.

Combined Anterior-Posterior Fusion Versus Posterior Alone Fusion for Cervical Myelopathy in Athetoid-Cerebral Palsy

STUDY DESIGN

Retrospective comparative study.

OBJECTIVES

Although some studies have discussed the use of lateral mass screws (LMSs) in patients with cerebral palsy (CP), it is unclear whether posterior LMS fixation alone is a suitable method. We aimed to compare the clinical, radiological, and surgical outcomes of 2 surgical modalities, namely, combined anterior-posterior (A-P) instrumented fusion and posterior fusion alone, in athetoid-type CP patients with cervical myelopathy (CM).

METHODS

We analyzed 63 patients with athetoid-CP and CM who underwent posterior fusion only with LMS (group A, 35 patients) and A-P fusion (group B, 28 patients). The primary outcome was the 1- and 3-year fusion rates for the surgical segments. The secondary outcomes included the clinical outcomes based on pain intensity determined using the visual analog scale score, neck disability index, and 17-point Japanese Orthopedic Association score, radiological, and surgical outcomes.

RESULTS

Fusion was achieved at 3 years postoperatively in 22 of 35 patients (63%) in group A and in 26 of 28 patients (93%) in group B (P = 0.02). The posterior neck pain intensity was also significantly lower in group B than in group A 2 and 3 years postoperatively (P = 0.02 and 0.01, respectively). The incidence of screw loosening and implant-related problems was higher in group A (60%) than in group B (21%) (P = 0.01). The other clinical and radiological parameters were similar between the groups.

CONCLUSIONS

For athetoid CP-induced CM, combined A-P fusion would result in superior clinical and radiological outcomes compared to posterior fusion alone.

Deep learning algorithm to evaluate cervical spondylotic myelopathy using lateral cervical spine radiograph

BACKGROUND

Deep learning (DL) is an advanced machine learning approach used in different areas such as image analysis, bioinformatics, and natural language processing. A convolutional neural network (CNN) is a representative DL model that is highly advantageous for imaging recognition and classification This study aimed to develop a CNN using lateral cervical spine radiograph to detect cervical spondylotic myelopathy (CSM).

METHODS

We retrospectively recruited 207 patients who visited the spine center of a university hospital. Of them, 96 had CSM (CSM patients) while 111 did not have CSM (non-CSM patients). CNN algorithm was used to detect cervical spondylotic myelopathy. Of the included patients, 70% (145 images) were assigned randomly to the training set, while the remaining 30% (62 images) to the test set to measure the model performance.

RESULTS

The accuracy of detecting CSM was 87.1%, and the area under the curve was 0.864 (95% CI, 0.780-0.949).

CONCLUSION

The CNN model using the lateral cervical spine radiographs of each patient could be helpful in the diagnosis of CSM.

Vertebral Body Rotational Osteotomy for Decompressing an Eccentrically Protruded Ossification of the Posterior Longitudinal Ligament: A Technical Note

Vertebral body sliding osteotomy has been reported as a technique to manage cervical myelopathy caused by ossification of the posterior longitudinal ligament. It involves mobilization and anteriorly translating the vertebral body and ossified mass as a whole. The main advantage of the procedure is decreased rate of complication such as dural tear, implant dislodgement, and pseudarthrosis, which demonstrates high rate in anterior cervical corpectomy and fusion. Vertebral body rotational osteotomy is a modification of vertebral body sliding osteotomy. It is indicated for laterally deviated ossified mass to achieve further decompression. This is a technical note describing the procedures of vertebral body rotational osteotomy.

Cervical Fusion-Requiring Mineral and Bone Disorder Disguised as Osteoporosis in a Chronic Kidney Disease Patient on Hemodialysis: A Case Report

Bony deformities and fragility fractures in end-stage renal disease (ESRD) patients on long-term hemodialysis can be caused by either osteoporosis or chronic kidney disease-mineral and bone disorder (CKD-MBD). Correct identification of the underlying mechanism is critical since the treatment methods differ, and one treatment approach could negatively affect the other. Cervical kyphosis, severe enough to require immediate surgical treatment, can be caused by uncontrolled CKD-MBD, albeit in limited cases. This report presents the case of a 61-year-old female with an 11-year history of hemodialysis treatment and severe cervical kyphosis with myelopathy, which required 2-stage spinal surgeries. Our report calls for a careful diagnostic approach in ESRD patients with skeletal disorders, the points to consider before calcium replacement, and early detection of fragility fractures in them. Moreover, early mobilization and weight-bearing after the surgical procedure may lead to better neurological and functional improvements.

Anterior Canal Reconstruction and Fusion for Myelopathy Caused by Degenerative Cervical Kyphosis and Stenosis With or Without Ossification of the Posterior Longitudinal Ligament

STUDY DESIGN

This was a retrospective study.

OBJECTIVE

To introduce an anterior surgical technique for myelopathy caused by degenerative cervical kyphosis and stenosis (DCKS) with or without ossification of the posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

The optimal approach in the treatment of DCKS remains a controversy because each anterior or posterior route surgery has advantages and disadvantages.

MATERIALS AND METHODS

In the period from June 2017 through June 2019, a consecutive cohort of adults diagnosed with DCKS underwent anterior canal reconstruction and fusion (ACRF). All patients underwent x-ray, computed tomography, and magnetic resonance imaging of the cervical spine. Radiologic assessment included kyphosis, canal area, canal reconstruction, OPLL, and spinal cord curvature and morphology. The Japanese Orthopaedic Association (JOA) scoring system was used to evaluate the neurological status. Surgery-related and implant-related complications were all recorded. Follow-up was carried out at 3, 6, 12, 24, and 36 months postoperation.

RESULTS

Fourty-one patients were included in the study, of which 19 presented with OPLL. Postoperatively, the canal area were significantly greater at last follow-up compared with preoperation (208.4 vs. 123.2 mm2; P=0.001). There was significant kyphosis correction (-17.6 vs. 8.5 degrees, P=0.001) at last follow-up. Ninety-six segmental canal reconstruction were performed, 89 (92.7%) reached bone fusion at both grooves with a mean time of 7.9 months. On sagittal magnetic resonance imaging, 33 (80.5%) patients presented with lordosis in the spinal cord curvature, 8 (19.5%) with straight. The mean JOA score at last follow-up was significantly better than preoperation (15.0 vs. 9.3 points; P<0.01). One patient presented with cerebrospinal fluid leakage, 1 with screw displacement and 2 with dysphagia.

CONCLUSION

ACRF, receiving good correction of kyphosis, amplified canal area, solid instrumented fusion and circumferential decompression, is an effective and safe surgical technique for cervical myelopathy caused by DCKS with or without OPLL.

LEVEL OF EVIDENCE

Level III-a retrospective analysis.

Short Plate with Screw Angle over 20 Degrees Improves the Radiologic Outcome in ACDF: Clinical Study

BACKGROUND

Anterior cervical discectomy and fusion surgery is a common procedure for degenerative cervical spine. This describes allospacer and implant-related outcomes, comparing medium plate-low screw angle and short plate-high screw angle techniques.

METHODS

From January 2016 to June 2019, 79 patients who underwent ACDF were prospectively enrolled. Patients were divided, depending on the plate-screw system used: medium plate-low screw angle (12.3 ± 2.5 to 13.2 ± 3.2 degrees), and short plate-high screw angle (22.8 ± 5.3 to 23.3 ± 4.7 degrees). Subsidence, ALOD, and sagittal cervical balance were analyzed using lateral cervical X-rays. NDI and VAS scores were also evaluated.

RESULTS

Age for medium plate-low-angled screw group is 58.0 ± 11.3 years, and 55.3 ± 12.0 in the short plate-high-angled screw group (p-value = 0.313). Groups were comparable in mean NDI (p-value = 0.347), VAS (p-value = 0.156), C2-C7 SVA, (p-value = 0.981), and lordosis angle (p-value = 0.836) at 1-year post-surgery. Subsidence was higher in the medium plate-low-angled screw than in the short plate-high-angled screw (25% and 8.5%, respectively, p-value = 0.045). ALOD is also more common in the medium plate group (p-value = 0.045).

CONCLUSION

Use of a short plate and insertion of high-angled screws (more than 20 degrees) has less chance of subsidence and occurrence of ALOD than the traditional technique of using medium plate and low angle.

Cervical Radiculopathy Focus on Characteristics and Differential Diagnosis

Cervical radiculopathy is characterized by neurological dysfunction caused by compression and inflammation of the spinal nerves or nerve roots of the cervical spine. It mainly presents with neck and arm pain, sensory loss, motor dysfunction, and reflex changes according to the dermatomal distribution. The most common causes of cervical radiculopathy are cervical disc herniation and cervical spondylosis. It is important to find the exact symptomatic segment and distinguish between conditions that may mimic certain cervical radicular compression syndromes through meticulous physical examinations and precise reading of radiographs. Non-surgical treatments are recommended as an initial management. Surgery is applicable to patients with intractable or persistent pain despite sufficient conservative management or with severe or progressive neurological deficits. Cervical radiculopathy is treated surgically by anterior and/or posterior approaches. The appropriate choice of surgical treatment should be individualized, considering the patient’s main pathophysiology, specific clinical symptoms and radiographic findings thoroughly.

Severe Cervical Spinal Kyphosis: Technical Case Reports on the Way of Microsurgical Management

A young man presented with quadriparesis due to severe kyphosis of the cervical spine. In the first posterior operation, the spinal cord was decompressed by laminectomies and posterior partial corpectomy through bilateral translateral mass and transforaminal approach followed by posterior stabilization and fusion. In the second operation, the cervical spine was stabilized and fused through an anterior approach. The patient recovered completely from his neurological deficit with very minimal neck movements. We report this case to describe the bilateral translateral mass and transforaminal partial posterior cervical corpectomy for spinal cord decompression followed by posterior and anterior stabilization and fusion.