Proximal junction kyphosis (PJK) is a common imaging finding after long-level fusion, and proximal junctional failure (PJF) is an aggravated form of the progressive disease spectrum of PJK. This includes vertebral fracture of upper instrumented vertebra (UIV) or UIV+1, instability between UIV and UIV+1, neurological deterioration requiring surgery. Many studies have reported on PJK and PJF after long segment instrumentation for adult spinal deformity (ASD). In particular, for spine deformity surgeons, risk factors and prevention strategies of PJK and PJF are very important to minimize reoperation. Therefore, this review aims to help reduce the occurrence of PJK and PJF by updating the latest contents of PJK and PJF by 2023, focusing on the risk factors and prevention strategies of PJK and PJF. We conducted a search on multiple database for articles published until February 2023 using the search keywords “proximal junctional kyphosis,” “proximal junctional failure,” “proximal junctional disease,” and “adult spinal deformity.” Finally, 103 papers were included in this study. Numerous factors have been suggested as potential risks for the development of PJK and PJF, including a high body mass index, inadequate postoperative sagittal balance and overcorrection, advanced age, pelvic instrumentation, and osteoporosis. Recently, with the increasing elderly population, sarcopenia has been emphasized. The quality and quantity of muscle in the surgical site have been suggested as new risk factor. Therefore, spine surgeon should understand the pathophysiology of PJK and PJF, as well as individual risk factors, in order to develop appropriate prevention strategies for each patient.

Objective: To identify risk factors and establish radiographic criteria for distal junctional failure (DJF) in patients with adult spinal deformity (ASD), who underwent fusion surgery stopping at L5.Methods: This retrospective study was undertaken from January 2016 to December 2020. Patients with ASD who underwent fusion surgery (≥5 levels) stopping at L5 were analyzed. DJF was defined as symptomatic adjacent segment pathology at the lumbosacral junction necessitating consideration for revision surgery. Demographic data and radiographic measurements were compared between the DJF and non-DJF groups. Receiver operating characteristic curve analysis was performed to identify the radiographic cutoff value for DJF.Results: Among 76 patients, 16 (21.1%) experienced DJF. DJF was associated with older age, antidepressant/anxiolytic medication, longer level of fusions, and worse preoperative sagittal alignment. Antidepressant/anxiolytic medication (odds ratio, 5.60) and preoperative pelvic incidence (PI)–lumbar lordosis (LL) mismatch>40° (odds ratio, 5.87) were independent risk factors for DJF. Without both factors, the incidence of DJF has been greatly reduced (9.1%). Two radiographic criteria were determined for DJF: last distal junctional angle (DJA)>-5° and Δ last DJA–post DJA>5°. When both criteria were met, the sensitivity and specificity of the DJF were 93.3% and 91.7%, respectively.Conclusion: Use of antidepressant/anxiolytic medication and preoperative PI–LL mismatch >40° were independent risk factors for DJF. DJF could be diagnosed using postoperative changes in the DJA. If both criteria were met, DJF could be strongly suggested.

Background/Objectives: Transforaminal endoscopic lumbar discectomy (TELD) is a minimally invasive spinal surgery known for its effectiveness, lower complication rates, faster recovery, and ability to be performed under local anesthesia. However, foraminal narrowing or access pain during the transforaminal approach can delay or hinder surgery in patients with far-lateral lumbar disc herniation (LDH). The objectives of this study were to identify predictive factors from preoperative magnetic resonance imaging (MRI) findings and demographics and discuss the optimization of surgical strategies. Methods: This retrospective study included 75 patients with far-lateral LDH who underwent TELD. Preoperative demographics and MRI findings were analyzed. Surgical data, including operative time, length of hospital stay, and intraoperative pain, were recorded. Postoperative outcomes, including complications, revision surgeries, and global outcomes based on the modified Macnab criteria, were evaluated. Preoperative clinical and radiological factors affecting the operative data and results were analyzed. Results: A higher foraminal stenosis grade was significantly correlated with prolonged operative time (p < 0.01) and extended hospital stay (p < 0.01). Extraforaminal LDH was associated with more severe access pain (p < 0.01) owing to increased nerve root irritation. Access pain was significantly correlated with operative time (p < 0.01) and hospital stay (p < 0.01). Appropriate surgical techniques and intraoperative pain management can mitigate these challenges. Conclusions: Preoperative MRI findings, particularly the grade of foraminal narrowing and herniation zone, can predict surgical difficulty and outcomes in TELD for far-lateral LDH. These insights can guide tailored strategies to reduce access pain and improve procedural success under local anesthesia.

Rationale: Osteopetrosis is a rare hereditary skeletal disorder characterized by increased bone density resulting from defective osteoclast-mediated bone resorption. This condition may lead to cranial nerve compression syndromes, with trigeminal neuralgia (TN) occurring infrequently. Patient concerns: We report the case of a 26-year-old woman with autosomal dominant osteopetrosis who presented with intractable, electric shock-like facial pain consistent with TN that was refractory to medical therapy. Diagnoses: Imaging revealed marked posterior fossa crowding with evidence of neurovascular compression of the left trigeminal nerve root entry zone, further compounded by cranial hyperostosis. Interventions: A staged surgical approach was undertaken. The first stage involved suboccipital craniectomy with C1 laminectomy to decompress the posterior fossa and restore cerebrospinal fluid dynamics. The second stage comprised microvascular decompression via a retrosigmoid approach after optimization of the intracranial space. Outcomes: Following completion of the staged surgical intervention, the patient achieved complete resolution of facial pain without neurological deficits. Symptom relief was sustained over a 5-year follow-up period, with no evidence of recurrence. Lessons: A staged decompressive approach represents an effective and durable treatment option for TN secondary to osteopetrosis, particularly in cases with markedly compromised posterior fossa anatomy. Initial posterior fossa decompression facilitates a safer and more effective subsequent microvascular decompression by improving the surgical corridor.

Background/Objectives: Transforaminal endoscopic lumbar foraminotomy (TELF) is increasingly used for lumbar foraminal stenosis, but direct comparisons with open lumbar foraminotomy remain limited. We compared 2-year clinical and perioperative outcomes between the procedures. Methods: We retrospectively reviewed consecutive patients who underwent single-level TELF or open lumbar foraminotomy between January 2020 and January 2024. The primary outcome was the change in leg-pain visual analog scale (VAS) score from baseline to 24 months. Results: Of 159 eligible patients, 147 completed 2-year follow-up (TELF, n = 72; open, n = 75). Improvement in leg-pain VAS score was 5.93 ± 1.60 points after TELF and 5.57 ± 1.44 points after open foraminotomy (mean difference, 0.36; 95% confidence interval, −0.14 to 0.85; p = 0.157). Two-year pain, disability, modified MacNab, complication, and reoperation outcomes did not differ significantly. TELF was associated with a shorter operative time (59.80 ± 15.37 vs. 81.20 ± 21.65 min), hospital stay (1.93 ± 0.68 vs. 6.84 ± 2.85 days), and return-to-work interval among patients who returned to work (3.91 ± 1.20 vs. 8.71 ± 2.45 weeks; all p < 0.001). Conclusions: TELF and open lumbar foraminotomy showed similar observed 2-year clinical outcomes, whereas the TELF treatment pathway was associated with faster perioperative recovery. These observational differences should not be interpreted as equivalence or as effects of surgical technique alone. Complete removal of the medial tip of the superior articular process is presented as a technical consideration for adequate foraminal decompression during TELF; its independent effect on outcomes was not evaluated.

Objective : This study aimed to evaluate the clinical and radiographic results of patients with adolescent idiopathic scoliosis (AIS) operated by a single neurosurgeon.Methods : A total of 139 consecutive patients with AIS who underwent corrective surgery by a single neurosurgeon were investigated between January 2011 and January 2024. Segmental instrumentation with pedicle screws was utilized for deformity correction. Demographic information, structural type of curve using Lenke classification, degree of correction achieved, total numbers of fusion levels, complications, and clinical/radiographic results were evaluated.Results : Most patients were adolescent girls (105 vs. 34) with an average age of 15.9 vs. 16.0, respectively. The average duration of follow-up was 4.5 years (0.1–13.0). Nine patients (6.6%) had levoscoliosis, and the remaining 130 had dextroscoliosis. Chiari malformation with syringomyelia was incidentally diagnosed in four patients (2.8%). Of the patients having Chiari malformation, two (50%) had levoscoliosis. The mean number of fused levels was 11.2. The mean value of the Cobb angle of the major structural curvature was 63.4° (43°–125°). The major structural curve’s average percentage of correction was 78.8%. The final postoperative SRS-22 average score significantly improved to 4.3±0.4 compared with the preoperative score of 3.8±0.5 (p<0.001). After the surgery, there were no observed cases of neurological deficits or need for screw repositioning. Revision fusion extension surgery was performed on one patient to treat postoperative shoulder imbalance.Conclusion : Patients with AIS treated by a neurosurgeon had acceptable clinical and radiographic results. However, AIS surgery necessitates a fundamental comprehension of pediatric spinal deformities, which is crucial. Furthermore, spine surgeons should be careful with patients who have levoscoliosis.