Contribution of MRI and imaging exams in the diagnosis of lumbar pseudarthrosis.

INTRODUCTION: The diagnosis of pseudoarthrosis is based on imaging and clinical exam findings. The standard for pseudarthrosis diagnosis remains postoperative observation through computer tomography (CT) and patient's symptoms. This can be further augmented by dynamic X-ray imaging or nuclear positron emission tomography (PET) CT to demonstrate an absence of fusion by showing a persistence of mobility. However, there is not a uniform diagnostic approach that is a standard of care amongst spine practioners. The aim of this study is to describe the timeline and diagnostic analysis for pseudoarthrosis between the initial surgery and follow-up procedure. METHODS: This is a single-center retrospective observational study. The aim was to enroll patients reoperated for pseudarthrosis after 1 or 2 level lumbar fusions, between August 1st, 2008 and August 1st, 2018. The exams were reviewed by one surgeon and one radiologist, defining a status either in favor of pseudarthrosis, or against it, or inconclusive, based on the radiological criteria mentioned below. We then investigated different combinations of exams and their specific chronology before a diagnosis was established. RESULTS: Forty-four patients were included, 70.5% male and with a mean age of 47.3 years. The median time between the 2 surgeries was 23.7 months. Plain X-rays supported the diagnosis in 38.7% of cases, dynamic X-rays showed hypermobility in 50% of cases. The CT-scan demonstrated pseudarthrosis in 94,4% of cases. A MODIC 1 signal was observed in 87,2% of cases on MRI. SPECT-CT showed a tracer uptake in 70% of cases. CONCLUSION: Reducing the time to reintervention is a key objective for improving the management and clinical outcomes of these patients. We suggest that MRI is an additional tool in combination with CT in the assessment of suspected mechanical pseudarthrosis, in order to optimize the diagnosis and shorten the time to revision surgery. LEVEL OF EVIDENCE: IV.

Iliocava junction to L4-L5 disc anatomical relationship in L5-S1 isthmic spondylolisthesis.

BACKGROUND: Anterior lumbar interbody fusion finds a place in L5-S1 isthmic spondylolisthesis (ISPL) treatment. Extension of this arthrodesis at L4-L5 level is sometimes required. Anterior approach of the L4L5 disc is considered difficult due to the anatomical relationship between the iliocava junction (ICJ) and the spine. HYPOTHESIS: Does the lumbosacral deformation induced by ISPL allows anterior approach of L4-L5 disc between the iliac? STUDY DESIGN: Retrospective radiographic analysis of consecutive patients. METHODS: This retrospective imaging study of a continuous series of 97 patients treated for an L5-S1 ISPL involved radiological parameters specific to ISPL and pelvic-sagittal balance. The distance between the ICJ and the L4 lower endplate was measured in millimeters. The factors influencing this distance were sought in order to identify a predictive model of high ICJ. RESULTS: The ICJ took a cranial position with respect to the L4-L5 disc with an average distance of 1.8mm±16.4. This distance was statistically higher in the case of high-grade ISPL (p<0.01). The high ICJ position was correlated with a high Taillard index (r=0.39; CI95% [0.13; 0.61]; p<.001) and a low lumbar-sacral angle (LSA) (r=-0.33; CI95% [-0.56; -0.06]; p<0.01). Among the parameters specific to spino-pelvic statics, pelvic incidence, pelvic tilt and lumbar lordosis had similar correlations (r>0.30). CONCLUSION: ISPL induces a geometric deformation of the lumbosacral hinge which modifies its anatomical relations with the ICJ. The anterior approach technique of L4-L5 disc in the presence of an L5-S1 ISPL is possible between the iliac veins for the large displacement and low LSA forms. LEVEL OF EVIDENCE: IV, retrospective analysis.

Anterior Cervical Idiopathic Hyperostosis and Dysphagia: The Impact of Surgical Management-Study of a Series of 11 Cases.

OBJECTIVE: To assess the efficacy and safety of surgery for dysphagia in anterior cervical idiopathic hyperostosis. METHODS: This retrospective study included 11 consecutive patients presenting with dysphagia and anterior cervical idiopathic hyperostosis. Computed tomography scans and dynamic swallowing fluoroscopies were performed. The site of compression and the size and position of osteophytes were measured. The clinical outcomes and complications were recorded. RESULTS: Two patients with anterior esophageal compression were found to have dysphagia caused by lower esophageal sphincter dysfunction. In the remaining 9 patients, the level of maximal compression was between C3 and C5 with the size of the osteophytes ranging from 8 to 17 mm. Intubation was challenging in 7 patients. Postoperative transient worsening of dysphagia was encountered in 3 patients. Two patients experienced severe complications including aphagia and respiratory compromise. Within 2 months of the operation, all patients reported satisfactory improvement of symptoms and a considerable gain in quality of life. No recurrence had occurred at final follow-up. CONCLUSIONS: Anterior cervical hyperostosis causing dysphagia typically affects older men and results from compression between C3 and C5 from osteophytes of variable sizes. Operative intervention can provide long-lasting resolution of symptoms but is complicated by difficulty in endotracheal intubation, postoperative dysphagia, and rarely respiratory compromise. A systematic preoperative ear, nose, and throat consultation is recommended to reduce these complications.

Cervical disc herniation: which surgery?

PURPOSE: Cervical disc herniation is a common pathology. It can be treated by different surgical procedures. We aimed to list and analyzed every available surgical option. We focused on the comparison between anterior cervical decompression and fusion and cervical disc arthroplasty. RESULTS: The anterior approach is the most commonly used to achieve decompression and fusion by the mean of autograft or cage that could also be combined with anterior plating. Anterior procedures without fusion have shown good outcomes but are limited by post-operative cervicalgia and kyphotic events. Posterior cervical foraminotomy achieved good outcomes but is not appropriate in a case of a central hernia or ossification of the posterior ligament. Cervical disc arthroplasty is described to decrease the rate of adjacent segment degeneration. It became very popular during the last decades with numerous studies with different implant device showing encouraging results but it has not proved its superiority to anterior cervical decompression and fusion. Anterior bone loss and heterotopic ossification are still to be investigated. CONCLUSION: Anterior cervical decompression and fusion remain the gold standard for surgical treatment of cervical disc herniation.

Instrumented Circumferential Fusion in Two Stages for Instable Lumbar Fracture: Long-Term Results of a Series of 74 Patients on Sagittal Balance and Functional Outcomes.

OBJECTIVE: To report the radiologic and functional results of a multicenter, prospective case series of patients with comminuted lumbar fractures treated with 2-stage circumferential arthrodesis. METHODS: A multicenter prospective case series of 74 patients with comminuted lumbar fractures was analyzed. The strategy entailed initial posterior osteosynthesis, followed by physical replacement with an expandable titanium cage filled with autologous bone via retroperitoneal lumbotomy. The mechanism of lesion formation and epidemiologic characteristics were recorded. Clinical and quality-of-life analyses (visual analog scale [VAS], Oswesty Disability Index [ODI], Short Form 12 [SF-12]) were performed over a minimum observation period of 1 year. Radiologic parameters, including deformity measurements, were recorded at each evaluation. Fusion was analyzed by means of a 1-year monitoring scan. RESULTS: The mean patient age was 38.1 years, and median duration of follow-up was 2.1 years (interquartile range, 1.3-2.9). The distribution of fractures according to the Magerl classification scheme was as follows: A, 64.8%; B, 16.7%; C, 18.5%. At the last follow-up, fusion was considered certain in 57 cases (77%). The mean VAS score was 2.1 ± 1.3, mean ODI was 14.7 ± 8.0, mean SF-12 Physical Component Summary score was 43.2 ± 9.3, and mean SF-12 Mental Component Summary score was 50.8 ± 5.9. Correction of the regional sagittal deformity was significant during the postoperative period, with a mean increase in lordosis of 9.0° (P < 0.0001). The loss of mean correction at the last follow-up (-2.9°) was not significant. CONCLUSIONS: Circumferential arthrodesis, including posterior osteosynthesis and physical replacement with an expandable cage and autologous graft, is applicable to the treatment of comminuted lumbar fractures. A high rate of fusion was obtained with significant and long-lasting correction of the sagittal deformity. Functional scores measured at 1 year suggest mild disability. The ODI, SF-12, and VAS scores were positively correlated with fusion at the last follow-up.

CT analysis of C2 pedicles morphology and considerations of useful parameters for screwing.

INTRODUCTION: Surgery of cervical spine steadily requires realizing posterior osteosynthesis. The anchoring of instrumentation in C2 steadily constitutes an important stake of prognosis. Pedicle screwing is one of the best options and remains associated with a low morbidity. The aim of this CT study is to provide, from a wide population, the descriptive anatomical parameters of C2 pedicles. The data enable this analysis of feasibility of C2 pedicles screwing. MATERIALS AND METHODS: A continuous and retrospective series have explored 100 CT scans of the cervical spine without finding C2 fracture. The software OSIRIX v5.0.2 has been used. The dimensions of the pedicles in C2 as length, diameter, and distance from the vertebral foramens have been measured from the preset posterior entry point. Their orientation has been described in the axial and sagittal plan by the pedicle transverse angle, the sagittal angle and the pedicle-lamina angle used as a visible mark during the procedure. At least, the feasibility of pedicle screwing has been evaluated using a diameter criterion higher than 4 mm. RESULTS: The dimensions analysis of 200 studied pedicles has found an average length as 26.18 mm, an average diameter as 5.18 mm and an average distance between the entry point and the vertebral foramen as 9.06 mm. Their orientations have an average PTA as 36.6° and a SA as 25.8°. The average of the PLA was 81.3. The screwing feasibility has been evaluated as 92.5 % in the whole series. CONCLUSION: These morphological data come from a large series give some help for the C2 pedicle screwing preoperative planning. These lean on 3D measures but also on accessible mark during the procedure and despite the difference of the patient orientation. A CT preoperative planning of the pedicle screwing remains essential because more than 7 % of the pedicles have a diameter lower than 4 mm.