BACKGROUND: Thoracic epidural capillary hemangioma is exceedingly rare, with only a few reported cases. The typical presentation usually includes chronic, progressive symptoms of spinal cord compression in middle-aged adults. To the authors\' knowledge, this case is the first report in the literature of acute traumatic capillary hemangioma rupture.
METHODS: A 22-year-old male presented with worsening lower extremity weakness and paresthesias after a fall onto his spine. Imaging showed no evidence of spinal fracture but revealed an expanding hematoma over 24 hours. Removal of the lesion demonstrated a ruptured capillary hemangioma.
CONCLUSIONS: This unique case highlights a rare occurrence of traumatic rupture of a previously unknown asymptomatic thoracic capillary hemangioma in a young adult.

BACKGROUND: Sacroiliac joint (SIJ) dysfunction can lead to significant pain and disability, greatly impairing quality of life. Arthrodesis may take up to 1 year to occur, after which revision can be considered. There is a need for highly accurate and reproducible techniques for revision that allow for purchase through undisturbed bone to prevent prolonged pain and disability. Moreover, a minimally invasive technique for revision would be favorable for recovery, particularly in elderly patients.
METHODS: An 84-year-old man with a prior history of lumbar fusion presented with severe buttock pain limiting ambulation and sitting because of the failure of arthrodesis after SIJ fusion 1 year earlier. He underwent revision using a triangular titanium implant (TTI) in an S2-alar-iliac (S2-AI) trajectory under robotic guidance, which is a novel technique not yet described in the literature. The patient\'s pain largely resolved, he was able to ambulate independently, and his quality of life improved tremendously. There were no complications of surgery.
CONCLUSIONS: Placement of a TTI using an S2-AI trajectory is a safe and effective method for revision that can be considered for elderly patients. Robot-assisted navigation can be used to facilitate an accurate and reproducible approach using a minimally invasive approach.

BACKGROUND: Neck pain is often chronic and disabling. Cervical facet joint injections and epidural steroid injections are frequently used to manage chronic neck pain and cervicogenic headaches. While minimal side effects are commonly associated with these treatments, severe complications are exceedingly rare.
METHODS: The authors report 4 cases of iatrogenic neurological injury after radiofrequency ablation (RFA) and epidural steroid injections. One patient experienced left shoulder, scapular, and arm pain with left arm and hand weakness that developed immediately after RFA for chronic neck pain. Electromyography/nerve conduction velocity (EMG/NCV) studies confirmed denervation changes in the left C8-T1 distribution. Three patients complained of numbness and weakness of the hands immediately after an interlaminar cervical epidural block. One of these patients underwent EMG/NCV that confirmed denervation changes occurring in the left C8-T1 distribution.
CONCLUSIONS: Spine surgeons and pain management specialists should be aware of neurological injuries that may occur after cervical RFA and epidural steroid injections, especially after a multilevel cervical procedure and with severe cervical spinal stenosis. EMG/NCV studies plays an important role in detecting and localizing neurological injury and in differentiating from conditions that mimic cervical root injuries, including brachial plexus trauma due to positioning and Parsonage-Turner syndrome.

Nerve root injuries associated with anterior lumbar interbody fusion (ALIF) are uncommonly reported in the literature. This case series and review aims to describe the etiology of L5 nerve root injury following ALIF at L5-S1.
The authors performed a single-center retrospective review of prospectively collected data of patients who underwent surgery between 2017 and 2019 who had postoperative L5 nerve root injuries after stand-alone L5-S1 ALIF. They also reviewed the literature with regard to nerve root injuries after ALIF procedures.
The authors report on 3 patients with postoperative L5 radiculopathy. All 3 patients had pain that improved. Two of the 3 patients had a neurological deficit, one of which improved.
Stretch neuropraxia from overdistraction is an important cause of postoperative L5 radiculopathy after L5-S1 ALIF. Judicious use of implants and careful preoperative planning to determine optimal implant sizes are paramount.

Nonfunctioning pituitary adenomas present without biochemical or clinical signs of hormone excess and are the second most common type of pituitary adenomas. The 2017 WHO classification scheme of pituitary adenomas differentiates null-cell adenomas (NCAs) and silent gonadotroph adenomas (SGAs). The present study sought to highlight the differences in patient characteristics and clinical outcomes between NCAs and SGAs.
The records of 1166 patients who underwent transsphenoidal surgery for pituitary adenoma between 2012 and 2019 at a single institution were retrospectively reviewed. Patient demographics and clinical outcomes were collected.
Of the overall pituitary adenoma cohort, 12.8% (n = 149) were SGAs and 9.2% (n = 107) NCAs. NCAs were significantly more common in female patients than SGAs (61.7% vs 26.8%, p < 0.001). There were no differences in patient demographics, initial tumor size, or perioperative and short-term clinical outcomes. There was no significant difference in the amount of follow-up between patients with NCAs and those with SGAs (33.8 months vs 29.1 months, p = 0.237). Patients with NCAs had significantly higher recurrence (p = 0.021), adjuvant radiation therapy usage (p = 0.002), and postoperative diabetes insipidus (p = 0.028). NCA pathology was independently associated with tumor recurrence (HR 3.64, 95% CI 1.07-12.30; p = 0.038), as were cavernous sinus invasion (HR 3.97, 95% CI 1.04-15.14; p = 0.043) and anteroposterior dimension of the tumor (HR 2.23, 95% CI 1.09-4.59; p = 0.030).
This study supports the definition of NCAs and SGAs as separate subgroups of nonfunctioning pituitary adenomas, and it highlights significant differences in long-term clinical outcomes, including tumor recurrence and the associated need for adjuvant radiation therapy, as well as postoperative diabetes insipidus. The authors also provide insight into independent risk factors for these outcomes in the adenoma population studied, providing clinicians with additional predictors of patient outcomes. Follow-up studies will hopefully uncover mechanisms of biological aggressiveness in NCAs and associated molecular targets.

Postoperative C5 palsy affects 7%-12% of patients who undergo posterior cervical decompression for degenerative cervical spine pathologies. Minimal evidence exists regarding the natural history of expected recovery and variables that affect palsy recovery. The authors investigated pre- and postoperative variables that predict recovery and recovery time among patients with postoperative C5 palsy.
The authors included patients who underwent posterior cervical decompression at a tertiary referral center between 2004 and 2018 and who experienced postoperative C5 palsy. All patients had preoperative MR images and full records, including operative note, postoperative course, and clinical presentation. Kaplan-Meier survival analysis was used to evaluate both times to complete recovery and to new neurological baseline-defined by deltoid strength on manual motor testing of the affected side-as a function of clinical symptoms, surgical maneuvers, and the severity of postoperative deficits.
Seventy-seven patients were included, with an average age of 64 years. The mean follow-up period was 17.7 months. The mean postoperative C5 strength was grade 2.7/5, and the mean time to first motor examination with documented C5 palsy was 3.5 days. Sixteen patients (21%) had bilateral deficits, and 9 (12%) had new-onset biceps weakness; 36% of patients had undergone C4-5 foraminotomy of the affected root, and 17% had presented with radicular pain in the dermatome of the affected root. On univariable analysis, patients\' reporting of numbness or tingling (p = 0.02) and a baseline deficit (p < 0.001) were the only predictors of time to recovery. Patients with grade 4+/5 weakness had significantly shorter times to recovery than patients with grade 4/5 weakness (p = 0.001) or ≤ grade 3/5 weakness (p < 0.001). There was no difference between those with grade 4/5 weakness and those with ≤ grade 3/5 weakness. Patients with postoperative strength < grade 3/5 had a < 50% chance of achieving complete recovery.
The timing and odds of recovery following C5 palsy were best predicted by the magnitude of the postoperative deficit. The use of C4-5 foraminotomy did not predict the time to or likelihood of recovery.

Although French psychiatrist-turned-neurosurgeon Jean Talairach (1911-2007) is perhaps best known for the stereotaxic atlas he produced with Pierre Tournoux and Gábor Szikla, he has left his mark on most aspects of modern stereotactic and functional neurosurgery. In the field of psychosurgery, he expressed critique of the practice of prefrontal lobotomy and subsequently was the first to describe the more selective approach using stereotactic bilateral anterior capsulotomy. Turning his attention to stereotaxy, Talairach spearheaded the team at Hôpital Sainte-Anne in the construction of novel stereotaxic apparatus. Cadaveric investigation using these tools and methods resulted in the first human stereotaxic atlas where the use of the anterior and posterior commissures as intracranial reference points was established. This work revolutionized the approach to cerebral localization as well as leading to the development of numerous novel stereotactic interventions by the Sainte-Anne team, including tumor biopsy, interstitial irradiation, thermal ablation, and endonasal procedures. Together with epileptologist Jean Bancaud, Talairach invented the field of stereo-electroencephalography and developed a robust scientific methodology for the assessment and treatment of epilepsy. In this article the authors review Talairach\'s career trajectory in its historical context and in view of its impact on modern stereotactic and functional neurosurgery.

Proximal junctional kyphosis (PJK) is a structural complication of spinal fusion in 5%-61% of patients treated for adult spinal deformity. In nearly one-third of these cases, PJK is progressive and requires costly surgical revision. Previous studies have suggested that patient body habitus may predict risk for PJK. Here, the authors sought to investigate abdominal girth and paraspinal muscle size as risk factors for PJK.
All patients undergoing thoracolumbosacral fusion greater than 2 levels at a single institution over a 5-year period with ≥ 6 months of radiographic follow-up were considered for inclusion. PJK was defined as kyphosis ≥ 20° between the upper instrumented vertebra (UIV) and two supra-adjacent vertebrae. Operative and radiographic parameters were recorded, including pre- and postoperative sagittal vertical axis (SVA), sacral slope (SS), lumbar lordosis (LL), pelvic tilt, pelvic incidence (PI), and absolute value of the pelvic incidence-lumbar lordosis mismatch (|PI-LL|), as well as changes in LL, |PI-LL|, and SVA. The authors also considered relative abdominal girth and the size of the paraspinal muscles at the UIV.
One hundred sixty-nine patients met inclusion criteria. On univariate analysis, PJK was associated with a larger preoperative SVA (p < 0.001) and |PI-LL| (p = 0.01), and smaller SS (p = 0.004) and LL (p = 0.001). PJK was also associated with more positive postoperative SVA (p = 0.01), ΔSVA (p = 0.01), Δ|PI-LL| (p < 0.001), and ΔLL (p < 0.001); longer construct length (p = 0.005); larger abdominal girth-to-muscle ratio (p = 0.007); and smaller paraspinal muscles at the UIV (p < 0.001). Higher postoperative SVA (OR 1.1 per cm), smaller paraspinal muscles at the UIV (OR 2.11), and more aggressive reduction in |PI-LL| (OR 1.03) were independent predictors of radiographic PJK on multivariate logistic regression.
A more positive postoperative global sagittal alignment and smaller paraspinal musculature at the UIV most strongly predicted PJK following thoracolumbosacral fusion.

L5-S1 stand-alone anterior lumbar interbody fusion (ALIF) is a reliable technique to treat symptomatic degenerative disc disease but remains controversial for treatment of isthmic spondylolisthesis. In the present study the authors aimed to identify risk factors of instrumentation failure and pseudarthrosis after stand-alone L5-S1 ALIF and to evaluate whether instrumentation failure influenced the rate of fusion.
The study included 64 patients (22 [34.4%] male and 42 [65.6%] female, mean age 46.4 years [range 21-65 years]) undergoing stand-alone L5-S1 ALIF using radiolucent anterior cages with Vertebridge plating fixation in each vertebral endplate. Clinical and radiographic data were reviewed, including age, sex, pelvic parameters, segmental sagittal angle (SSA), C7/sacro-femoral distance (SFD) ratio, C7 sagittal tilt, lumbar lordosis (LL), segmental LL, percentage of L5 slippage, L5-S1 disc angle, and posterior disc height ratio. Univariate and multivariate analyses were used to identify risk factors of instrumentation failure and pseudarthrosis.
At a mean follow-up of 15.9 months (range 6.6-27.4 months), fusion had occurred in 57 patients (89.1%). Instrumentation failure was found in 12 patients (18.8%) and pseudarthrosis in 7 patients (10.9%). The following parameters influenced the occurrence of instrumentation failure: presence of isthmic spondylolisthesis (p < 0.001), spondylolisthesis grade (p < 0.001), use of an iliac crest bone autograft (p = 0.04), cage height (p = 0.03), pelvic incidence (PI) (p < 0.001), sacral slope (SS) (p < 0.001), SSA (p = 0.003), and LL (p < 0.001). Instrumentation failure was statistically linked to the occurrence of L5-S1 pseudarthrosis (p < 0.001). On multivariate analysis, no risk factors were found.
L5-S1 isthmic spondylolisthesis and high PI seem to be risk factors for instrumentation failure in case of stand-alone L5-S1 ALIF, findings that support the necessity of adding percutaneous posterior pedicle screw instrumentation in these cases.

The sacrum forms the distal end of the spine and communicates with the pelvis. Fractures involving the sacrum are complex and may disrupt this vital communication. Neglecting these fractures may result in malunion, which often causes significant alteration in the pelvic parameters and sagittal balance. Management of ensuing deformities is complex and poorly described. The authors present a case of sacral malunion with sagittal imbalance treated with a low lumbar osteotomy.