Louis Chenin

Minimally invasive transforaminal lumbar interbody fusion with the ROSA(TM) Spine robot and intraoperative flat-panel CT guidance.

BackgroundCircumferential arthrodesis is commonly used to treat degenerative lumbar diseases. Minimally invasive techniques may enable faster recovery and reduce the incidence of postoperative infections.MethodsWe report on the surgical technique of a transforaminal lumbar interbody fusion (TLIF) procedure performed with the assistance of a new robotic device (ROSATM Spine) and intraoperative flat-panel CT guidance.ConclusionsThe combined use of this new robotic device and intraoperative CT enables accurate and safe arthrodesis in the treatment of degenerative lumbar disc diseases.

Evaluation of Screw Placement Accuracy in Circumferential Lumbar Arthrodesis Using Robotic Assistance and Intraoperative Flat-Panel Computed Tomography

BACKGROUNDnNeuronavigation has become a common means of placing pedicle screws in vertebral arthrodesis, because it reduces the incidence of complications related to poor screw positioning.nnnOBJECTIVEnThe To evaluate the accuracy of pedicle screw placement during lumbar arthrodesis performed with the new ROSA Spine robot and intraoperative flat-panel computed tomography (fpCT) guidance.nnnMETHODSnWe performed a descriptive, observational, retrospective, single-center study of patients having undergone transforaminal lumbar interbody fusion (TLIF) for degenerative pathologies with the ROSA Spine robot and intraoperative fpCT guidance. The primary endpoint was the presence or absence of pedicle wall breach, as assessed from the fpCT scan. Screw placement was graded according to Ravis classification.nnnRESULTSnTwenty-five patients were operated on between November 2014 and July 2016; 21 underwent minimally invasive TLIF, and 4 underwent open TLIF. The mean ± standard deviation operating time was 241 ± 49.8 minutes. Of the 110 screws placed, 101 (91.8%) were completely within the pedicle (Ravi grade A), 5 (4.5%) had axa0pedicle wall breach <2 mm (grade B), 2 (1.8%) had a pedicle wall breach of 2-4 mm (grade C), and 2 had pedicle wall breach >4 mm (grade D) (1.8%). One screw (axa0grade D) was replaced during surgery. None of the breaches were symptomatic.nnnCONCLUSIONSnWhen coupled with fpCT, the ROSA Spine robot is a reliable, accurate means of performing lumbar pedicle screwing.

Microsurgical anatomy of branches of musculocutaneous nerve: clinical relevance for spastic elbow surgery.

PurposeThe neurotomy of musculocutaneous nerve is a treatment for patients who suffer from spastic elbow flexion when medical and reeducative treatments have failed. It consists in sectioning motor branches of musculocutaneous nerve which are destined to the biceps brachii and brachialis muscles, both being the main elbow flexor muscles. The aim of this study was to analyse the distance, where each motor branch arises from the musculocutaneous nerve to both biceps brachii and brachialis muscles, to establish precisely the localisation and length of the necessary incision to reach its branches for surgery.Materials and methodsEighteen musculocutaneous nerves from ten cadavers were dissected. None of them reported with a previous pathology. The cadavers were laid on the back with 30–35° of abduction, a complete extension, and supination of the upper limb.ResultsThe localization of motor branches was to be found in the middle third of the upper arm, with an average from the base of the humeral major tubercle of 11.46, 12.40, and 12.87xa0cm for the biceps brachii and 16.36, 19.10, and 16.88xa0cm for the brachialis muscle.ConclusionThe incision needed to reach the motor branches of the musculocutaneous nerve should be localised between 10 and 20xa0cm from the major humeral tubercle and may be shorter than usual.

Robot-Assisted Radiofrequency Ablation of a Sacral S1-S2 Aggressive Hemangioma

BACKGROUNDnAggressive vertebral hemangiomas are rare tumors of the spine. The treatment management strategy usually consists of vertebroplasty, radiation therapy, or, in rare cases of surgical strategy.nnnCASE DESCRIPTIONnWe present a case of a bulging sacral S1-S2 hemangioma in the spinal canal that could not be managed in the usual manner.nnnCONCLUSIONnHere we demonstrate the usefulness of radiofrequency ablation technique as an alternative treatment, as well as robotic assistance for optimal placement of the ablation probe within the lesion.

A median sacral artery anterior to the iliocaval junction: a case report—anatomical considerations and clinical relevance for spine surgery

Background and importanceThe median sacral artery (MSA) is a relatively small vessel that always arises from the posterior, terminal part of the infrarenal aorta. In most cases, the MSA runs behind the iliocaval junction. Here, we describe a very rare case of an MSA running in front of this junction.Case reportDuring a human cadaveric dissection of the retroperitoneal area, we unexpectedly observed that the MSA passed in front of the left common iliac vein.ConclusionThe anatomy of the MSA has been extensively described and variations are quite rare. On the basis of this specific case, knowledge of the anatomic interactions between the MSA and other lumbar retroperitoneal vessels may help to avoid potential complications during surgery.

Microsurgical anatomy of the Adamkiewicz artery-anterior spinal artery junction

PurposeThe aim of this study is to describe the anterior spinal artery–Adamkiewicz artery (ASA–AKA) junction and establish a classification allowing defining the neurological risk in either thoracoabdominal aorta aneurysm treatment and in anterior or transforaminal thoracolumbar spine surgery.MethodsFifteen spinal cords of fresh cadavers were dissected. Both lumbar arteries and ASA were injected with strongly diluted red-colored silicon.ResultsThe dural crossing of AKA was located on the left side in 86xa0% of cases, between T8 and T10 in 73.33xa0% of cases and L1–L2 in 26.67xa0% of cases. The average diameter of the ascending branch of AKA was 1.10xa0mm (range 0.8–1.9xa0mm), and its average length was 30.27xa0mm (range 12.3–60xa0mm). The AKA’s arch average diameter was 11.3xa0mm (range 9–20xa0mm) with an open downward angle average of 20.1° (range 11°–30°). The descending branch of AKA which was a continuation of ASA had an average diameter of 1.33xa0mm (range 0.8–1.86xa0mm). The ASA at the top of the arch had an average diameter of 0.74xa0mm (range 0.2–1.77xa0mm). According to these findings, we have proposed a new classification with two types of junctions. The type I and its variant correlated to high neurological risk were present in 93.33xa0% of cases. The type II, correlated to medium or low neurological risk, was present in 6.67xa0% of cases.ConclusionThese anatomical findings allow a planning of the neurological risk before thoracoabdominal aorta aneurysm or thoracolumbar anterior or transforaminal spine surgery.

An unusual, duplicate origin of the anterior choroidal artery with aneurysm: a case report

Background and importanceAneurysms of the anterior choroidal artery (AChoA) are rare and often difficult to treat. Variations may be present and must be identified prior to treatment. We report a unique case of a ruptured aneurysm located at the origin of a duplicate branch of the AChoA.Clinical presentationA 56-year-old male was admitted to our university hospital for coma. A brain CT scan showed a subarachnoid hemorrhage, and CT angiography revealed a duplication of the right AChoA, with an aneurysm located at the branch’s origin. We decided to embolize this aneurysm. Four weeks later, our patient was able to transfer to the rehabilitation unit.ConclusionTo the best of our knowledge, this is one of the first descriptions of an aneurysm located at the origin of a duplicate branch of the AChoA.

Unilateral duplicated abducens nerve coursing through both the sphenopetroclival venous gulf and cavernous sinus: a case report

In this anatomy report, we describe the first case of abducens nerve duplication limited to the sphenopetroclival venous gulf and the cavernous sinus. The objective point of division of the two duplicated roots was localized at the gulfar face of the dural porus, just distal to the unique cisternal trunk of the abducens nerve, as it pierced the petroclival dural mater. In the gulfar segment, both roots traveled through a variant of Dorello’s canal called the “petrosphenoidal canal” and remained separated through the posterior half of the cavernous sinus. Both roots finally fused in the anterior half of the cavernous sinus to innervate the lateral rectus muscle as a single trunk. Although many variants of the abducens nerve have been reported over the recent decades, this anatomic variation has never been previously described and enriches the continuum of abducens nerve variations reported in the literature data. Awareness of this variation is crucial for neurosurgeons, especially during clival or petrosal surgical approaches used for resection of skull base chordomas.

A case of Erdheim-Chester disease with spinal cord compression and sphenoid sinus involvement

Erdheim-Chester disease is a rare form of non-Langerhans cell histiocytosis. It is an inflammatory disorder associated with BRAF V600E mutation in 50% of cases. This multisystem disease is rarely associated with spinal involvement. Neurological involvement is an independent predictive factor of poor prognosis. The diagnosis is histopathological based on CD68-positive and CD1A-negative histiocytes. Treatment with interferon-alpha is an independent predictor of survival in Erdheim-Chester disease and vemurafenib has also been shown to be effective for BRAF V600E mutation. We report a clinical case of a 51-year-old patient with multiple and rare locations of Erdheim-Chester disease, particularly at the sphenoid sinus.

Cortical and subcortical functional neuroanatomy for low-grade glioma surgery

Knowledge of the encephalon anatomy is crucial for neurosurgical practice, especially the main cortical functional structures and their connections. General organisation of the encephalon is presented with frontal, parietal, occipital, temporal, limbic and insular lobes and their Brodmann correspondence. Secondly, subcortical anatomy will be presented with main white matter fasciculi in three separated categories: association, commissural and projection fibers. Main association fibers are inferior occipitofrontal fasciculus, superior longitudinal fasciculus, arcuate fasciculus, inferior longitudinal fasciculus, uncinate fasciculus, and cingulum. Commissural fibers include anterior commissure, corpus callosum and fornix. Projection fibers are internal capsule and optic radiations.