Young-Joon Kwon

Objective: Postoperative delirium is a common disorder after surgery in the older population leading to difficulty in the postoperative period. However, there are currently insufficient understanding and few studies on postoperative delirium in spine surgery. The purpose of the present study was to evaluate the incidence and risk factors leading to postoperative delirium after spine surgery in an age-matched cohort. Methods: This study retrospectively reviewed the incidence of delirium in 3,581 patients who underwent spine surgery from 2005 to 2019 at a single institution. The authors reviewed the patient history for unmodifiable and modifiable factors in the past, pre-and postoperative blood lab results, and intraoperative factors. Results: Each patient in the delirium group was age-matched with 2 patients in the delirium-negative group with the allocated propensity score (1:2). Overall incidence rate of postoperative delirium was 3.07% (110/3,581). The incidence of postoperative delirium increased with increasing age. Multivariate analysis shows that smoking history (p=0.008), the use of psychiatric medication (p=0.004), the use of steroids (p=0.041), preoperative C-reactive protein (CRP; p=0.001), blood chloride (Cl) levels (p=0.006), fasting blood glucose levels (p=0.004), Intraoperative transfusions (p=0.044), and postoperative CRP (p=0.040), erythrocyte sedimentation rate (p≤0.001), and blood Cl levels (p=0.005) were identified as significant risk factors for postoperative delirium. Conclusion: It is important to recognize and check the significant risk factors of postoperative delirium after spine surgery. Dedicated perioperative care should be performed to prevent postoperative delirium in patients with the risk factors.

Objectives:To compare the reliability of two recently reported MR grading systems of cervical neural foraminal stenosis (CNFS) and their correlation with clinical manifestations.Methods:We evaluated 188 patients (M:F = 80:108, mean age of 41 years) who visited our institution and underwent oblique sagittal MR imaging of the cervical spine. Two radiologists evaluated the MRI findings for the presence and grade of CNFS at the narrowest point, with the grading systems (Park, Kim and mKim systems) suggested by Park et al. and Kim et al. More than one positive neurologic sign and more than one neurologic clinical symptom was considered a positive neurologic manifestation (PNM) of each foraminal stenosis. Inter-observer agreement between two readers was analyzed using kappa statistics. Nonparametric correlation analysis (Spearman’s correlation) was used to evaluate correlation coefficients (R) to assess the relationship between CNFS grade and clinical manifestations.Results:Both the Park and mKim systems demons...

To report long-term clinical and radiological outcomes of minimally invasive posterior cervical foraminotomy (MI-PCF) performed in patients with unilateral single-level cervical radiculopathy. Of forty-six patients who underwent MI-PCF for unilateral single-level radiculopathy between 2005 and 2013, 33 patients were included in the study, with a mean follow-up of 32.7 months. Patients were regularly followed for clinical and radiological assessment. Clinical outcome was measured by visual analogue scale (VAS) for the neck/shoulder and arm, and the neck disability index (NDI). Radiological outcome was measured by focal/global angulation and disc height index (DHI). Outcomes after MI-PCF were evaluated as changes of clinical and radiological parameters from the baseline. Mixed effect model with random patients' effect was used to test for differences in the clinical and radiological parameters repeat measures. There were no complications and all patients had an uneventful recovery during the early postoperative period. VAS scores for neck/shoulder and arm improved significantly in the early postoperative period (3 months) and were maintained with time (p<0.001). NDI improved significantly post-operatively and tended to decrease gradually during the follow-up period (p<0.001). There were no statistically significant changes in focal and global angulation at follow-up. Percent DHIs of the upper adjacent or operated disc were maintained without significant changes with time. During the follow-up, same site recurrence was not noted and adjacent segment disease requiring additional surgery occurred in two patients (6%) on the contra-lateral side. MI-PCF provides long-term pain relief and functional restoration, accompanied by good long-term radiological outcome.

Lumbar spinal stenosis is a common degenerative spine disease that requires surgical intervention. Currently, there is interest in minimally invasive surgery and various technical modifications of decompressive lumbar laminectomy without fusion. The purpose of this study was to present the author's surgical technique and results for decompression of spinal stenosis. The author performed surgery in 57 patients with lumbar spinal stenosis between 2006 and 2010. Data were gathered retrospectively via outpatient interviews and telephone questionnaires. The operation used in this study was named central decompressive laminoplasty (CDL), which allows thorough decompression of the lumbar spinal canal and proximal two foraminal nerve roots by undercutting the lamina and facet joint. Kyphotic prone positioning on elevated curvature of the frame or occasional use of an interlaminar spreader enables sufficient interlaminar working space. Pain was measured with a visual analogue scale (VAS). Surgical outcome was analyzed with the Oswestry Disability Index (ODI). Data were analyzed preoperatively and six months postoperatively. The interlaminar window provided by this technique allowed for unhindered access to the central canal, lateral recess, and upper/lower foraminal zone, with near-total sparing of the facet joint. The VAS scores and ODI were significantly improved at six-month follow-up compared to preoperative levels (p75% of initial VAS score) of back/buttock and leg was observed in 75.0% and 76.2% of patients, respectively. CDL is easily applied, allows good field visualization and decompression, maintains stability by sparing ligament and bony structures, and shows excellent early surgical results.

Kwon YJ. J Korean Med Sci. 2013 Jun;28(6):939-945. https://doi.org/10.3346/jkms.2013.28.6.939

Objective: One of the main limitations of vertebroplasty is the excessive pressure required for injection of sufficient cement into a vertebral body. Kyphoplasty can be used to reduce injection pressure by making a void with a balloon tamp. The author presents a technique of making small voids to reduce cement delivery pressure during vertebroplasty that involves a simple modification of the conventional technique. Methods: The author performed this modified vertebroplasty in 48 patients with an acute vertebral compression fracture. Small voids and micro-connections with the fracture gaps in the vertebral body were created using a curved probe placed into the vertebral body through a working cannula. Visual analogue scale (VAS) scores were measured preoperatively and at 1 week and 3 months postoperatively. Forty patients with osteoporotic VCFs were followed for a mean period of 6months. Results: All 48 patients showed a significant reduction in visual analogue pain scores at 1 week and 3 months postoperatively versus preoperative levels (pConclusion: The described modification of vertebroplasty involving the creation of small cavities using a curved probe appears to control cement injection easily during the procedures and minimize cement leakage-related complications.