The Posterior Cranial Vertical Line: A Novel Radiographic Marker for Classifying Global Sagittal Alignment.

OBJECTIVE: To define a novel radiographic measurement, the posterior cranial vertical line (PCVL), in an asymptomatic adult population to better understand global sagittal alignment. METHODS: We performed a multicenter retrospective review of prospectively collected radiographic data on asymptomatic volunteers aged 20-79. The PCVL is a vertical plumb line drawn from the posterior-most aspect of the occiput. The horizontal distances of the PCVL to the thoracic apex (TA), posterior sagittal vertical line (PSVL, posterosuperior endplate of S1), femoral head center, and tibial plafond were measured. Classification was either grade 1 (PCVL posterior to TA and PSVL), grade 2 (PCVL anterior to TA and posterior to PSVL), or grade 3 (PCVL anterior to TA and PSVL). RESULTS: Three hundred thirty-four asymptomatic patients were evaluated with a mean age of 41 years. Eighty-three percent of subjects were PCVL grade 1, 15% were grade 2, and 3% were grade 3. Increasing PCVL grade was associated with increased age (p < 0.001), C7-S1 sagittal vertical axis (SVA) (p < 0.001), C2-7 SVA (p < 0.001). Additionally, it was associated with decreased SS (p = 0.045), increased PT (p < 0.001), and increased knee flexion (p < 0.001). CONCLUSION: The PCVL is a radiographic marker of global sagittal alignment that is simple to implement and interpret. Increasing PCVL grade was significantly associated with expected changes and compensatory mechanisms in the aging population. Most importantly, it incorporates cervical alignment parameters such as C2-7 SVA. The PCVL defines global sagittal alignment in adult volunteers and naturally distributes into 3 grades, with only 3% being grade 3 where the PCVL lies anterior to the TA and PSVL.

Functional Outcome After Spinal Meningioma Surgery. A Nationwide Population-Based Study.

OBJECTIVE: To describe and analysed the functional outcome (FO) after spinal meningioma (SM) surgery. METHODS: We processed the système national des données de santé (SNDS) i.e. , the French national administrative medical database to retrieve appropriate cases. We analysed the International Classification of Diseases 10 codes to assess the FO. Logistic models were implemented to search for variables associated with a favourable FO i.e. , a patient being independent at home without disabling symptom. RESULTS: A total of 2,844 patients were identified of which 79.1% were female. Median age at surgery was 66 years, interquartile range (IQR) (56-75). Ninety-five point nine percent of the SMs were removed through a posterior ± lateral approach and 0.7% need an associated stabilisation. Benign meningioma represented 92.9% and malignant 2.1%. Median follow-up was 5.5 years, IQR (2.1-8), and at data collection 9% had died. The FO was good and increased along the follow-up: 84.3% of the patients were alive and had not associated symptoms at one year, 85.9% at 2 and 86.8% at 3 years. Nonetheless, 3 years after the surgery 9.8% of the alive patients still presented at least one disabling symptom of which 2.7% motor deficit, 3.3% bladder control problem, and 2.5% gait disturbance. One point seven percent were care-provider dependent and 2.1% chair or bedfast. In the multivariable logistic regression an older age at surgery (odds ratio [OR], 0.37; 95% confidence interval [CI], 0.29-0.47, p < 0.001), a high level of comorbidities (OR, 0.71; 95% CI, 0.66-0.75, p < 0.001), and an aggressive tumor (OR, 0.49; 95% CI, 0.33-0.73; p < 0.001) were associated with a worse FO. CONCLUSION: FO after meningioma surgery is favourable but, may be impaired for older patients with a high level of comorbidities and aggressive tumor.

Cervical Inclination Angle: Normative Values in an Adult Multiethnic Asymptomatic Population.

OBJECTIVE: The role of the craniocervical complex in spinal sagittal alignment has rarely been analyzed but it may play a fundamental role in postoperative mechanical complications. The aim of the study is to analyze the normative value of the cervical inclination angle (CIA) in an adult asymptomatic multiethnic population. METHODS: Standing full-spine EOS of adult asymptomatic volunteers from 5 different countries were analyzed. The CIA was analyzed globally and then in each decade of life. Different ethnicities were compared. Comparisons between different groups was performed using a t-test and statistical significance was considered with a p-value < 0.05. RESULTS: EOS of 468 volunteers were analyzed. The global mean CIA was 80.2° with a maximum difference of 9° between T1 and T12 (p < 0.001). The CIA remains constant until 60 years old then decreases significantly passing from a mean value before 20 years old of 82.25° to 73.65° after 70 years old. A statistically significant difference was found between the Arabics and other ethnicities with the formers having an inferior CIA: this was related to a mean older age (p < 0.05) and higher body mass index (p < 0.05) in the Arabics. CONCLUSION: The CIA remains constant until 60 years old and then reduces slightly but never under 70°. This angle is helpful to evaluate the lever arm at the upper instrumented vertebra after an adult spinal deformity surgery and could predict the occurrence of a proximal junctional kyphosis when its value is lower than normal. Further clinical studies must confirm this theory.