3D Printer Application for Endoscope-Assisted Spine Surgery Instrument Development: From Prototype Instruments to Patient-Specific 3D Models

Comminuted Radial Head Fracture in All-arthroscopic Repair of Elbow Fracture-dislocation: Is Partial Excision of the Radial Head an Acceptable Treatment Option?

BACKGROUND: In elbow fracture-dislocation, partial excision of the comminuted radial head fracture that is not amenable to fixation remains controversial considering the accompanying symptoms. This study was undertaken to evaluate the results of radial head partial excision when the comminuted radial head fracture involved < 50% of the articular surface in all-arthroscopic repair of elbow fracture-dislocation. METHODS: Patients were divided into two groups based on the condition of the radial head fracture. In Group A, the patients had a radial head comminuted fracture involving < 50% of the articular surface, and underwent arthroscopic partial excision. Group B was the non-excision group comprising patients with stable and non-displacement fractures. Follow-up consultations were conducted at 6 weeks and at 3, 6, 12, and 24 months after surgery. RESULTS: In all, 19 patients (Group A: 11; Group B: 8) met the inclusion criteria and were enrolled in the study. At the final follow-up, all 19 patients showed complete resolution of elbow instability. No significant differences were observed in the range of motion, visual analogue scale score, and Mayo elbow performance score between groups. Radiological findings did not show any complications of the radiocapitellar joint. However, nonunion of the coracoid fracture was observed in 3 patients (Group A: 1; Group B: 2), without any accompanying instability and clinical symptoms. CONCLUSIONS: Considering that the final outcome is coronoid fracture fixation and lateral collateral ligament complex repair for restoring elbow stability, arthroscopic partial excision for radial head comminuted fractures involving < 50% of articular surface is an effective and acceptable treatment for elbow fracture-dislocation.

Comparing the Use of Single and Double Interlocking Distal Screws on a Polarus Intramedullary Nail for Humeral Shaft Fractures

BACKGROUND: Our aim was to make a comparative analysis of radiological and clinical outcomes of using either one or two interlocking distal screws on a Polarus intramedullary nail for the internal fixation of humeral shaft fractures. METHODS: From January 2008 to March 2014, we enrolled 26 patients with humeral shaft fractures who were operated on using intramedullary nails. The patients were divided into 2 groups according to how many interlocking distal screws were used to lock the Polarus nail: in group 1, a single interlocking distal screw was used in 12 patients; and in group 2, double interlocking distal screws, in 14 patients. We compared the degree of recovery of the displaced fracture fragments between the two groups. To compare the nonunion and shoulder function, we assessed each patient's modified American Shoulder and Elbow Surgerns (ASES) score. RESULTS: We found that 10 of 12 fractures achieved union in group 1, and 13 of 14 fractures, in group 2. We did not find a meaningful difference in the time to bone union between the two groups. The percentage of recovery of displaced fracture fragments until union was 66.9% for group 1 and 59.41% for group 2. At the final follow-up, we found that the scores for shoulder joint modified ASES was 78.7 for group 1 and 80.7 for group 2. CONCLUSIONS: Our results show that if locked appropriately, even a single screw on a Polarus nail can provide satisfactory radiological union and improved clinical outcome after intramedullary nailing of humeral shaft fractures.

Comparing the Use of Single and Double Interlocking Distal Screws on a Polarus Intramedullary Nail for Humeral Shaft Fractures

BACKGROUND: Our aim was to make a comparative analysis of radiological and clinical outcomes of using either one or two interlocking distal screws on a Polarus intramedullary nail for the internal fixation of humeral shaft fractures. METHODS: From January 2008 to March 2014, we enrolled 26 patients with humeral shaft fractures who were operated on using intramedullary nails. The patients were divided into 2 groups according to how many interlocking distal screws were used to lock the Polarus nail: in group 1, a single interlocking distal screw was used in 12 patients; and in group 2, double interlocking distal screws, in 14 patients. We compared the degree of recovery of the displaced fracture fragments between the two groups. To compare the nonunion and shoulder function, we assessed each patient's modified American Shoulder and Elbow Surgerns (ASES) score. RESULTS: We found that 10 of 12 fractures achieved union in group 1, and 13 of 14 fractures, in group 2. We did not find a meaningful difference in the time to bone union between the two groups. The percentage of recovery of displaced fracture fragments until union was 66.9% for group 1 and 59.41% for group 2. At the final follow-up, we found that the scores for shoulder joint modified ASES was 78.7 for group 1 and 80.7 for group 2. CONCLUSIONS: Our results show that if locked appropriately, even a single screw on a Polarus nail can provide satisfactory radiological union and improved clinical outcome after intramedullary nailing of humeral shaft fractures.

A Case of Complicated Silicosis with a Complex Clinical Course in a Glass Manufacturing Worker

We reported a case of complicated silicosis that occurred in a glass manufacturing plant worker who had presumably been exposed to low-concentration free silica for almost 20 years. To the best of our knowledge this report is the first in the Republic of Korea. The physician's first impression was cancer since the enlargement of neck and supraclavicuar lymph nodes had clearly progressed and metastasis was suspected in ultrasonography. However, it turned out to be reactive hyperplasia and anthracosis. Although lung cancer was suspected and tests were performed in 2 hospitals due to repetitive cough and dyspnea, along with weight loss of approximately 10% over the course of 7 months, the patient was eventually diagnosed with complicated silicosis and pneumothorax occurred after 1 year. Herein, we report this case with a literature review.

Proximal Femur and Lumbar Spine's DXA T-score Concurrence in Diagnosis of Osteoporosis / 대한골다공증학회지

OBJECTIVES: To evaluate the correlation between T-score of lumbar spine and that of proximal femur using dual energy x-ray absorptiometry (DXA) and the accuracy of the diagnosis of osteoporosis. MATERIAL AND METHODS: From December 2009 to January 2012, 300 female patients were selected who underwent bone mineral density (BMD) test using DXA. After measuring BMD of proximal femur and lumbar spine, the score of BMD in each age group was compared by two sites. Also, the concordance of the diagnosis of osteoporosis was evaluated. RESULTS: The result showed significantly lower T-score and BMD as it goes to the elderly group. As it goes for 60's age group and even more for 70's age group, lumbar spine showed lower BMD than proximal femur. In all age groups, lumbar spine and proximal femur T-score showed significant correlation; however, it showed the least states at 60's age group. Discordance rate of osteoporosis diagnosis was 33% and 47.3% each at lowest t-score and total t-score. 60's age group showed the highest discordance rate, and osteoporosis group showed the highest rate. CONCLUSIONS: When measuring BMD for diagnosis of osteoporosis, since it shows significant discordance between proximal femur and lumbar spine, it is necessary to measure BMD simultaneously on both parts.

Comparison of Ultrasonography and Magnetic Resonance Imaging in Measurement of Lumbar Spine Anatomic Structures / 대한정형외과학회잡지

PURPOSE: The aim of this study was to determine the usefulness of ultrasonography for lumbar anatomical structure measurement. MATERIALS AND METHODS: From January 2011 to April 2011, 41 patients (22 males, 19 females) with back pain who visited the outpatient department and underwent lumbar magnetic resonance imaging (MRI) were selected. In each level of L4 and L5, we measured the longest distance and horizontal distance between each inferior articular process based off a spinous process. We also measured the distance between the spinous process tip and the vertebral body posterior surface and the thickness and width of the multifidus muscle. All distances were measured with ultrasonography and MRI and the two measurement results were compared. RESULTS: Using ultrasonography and MRI, we measured the distance between the spinous process tip and the posterior surface of the body. The distances were 39.16+/-8.71 mm/39.53+/-6.01 mm at L4 and 38.32+/-9.66 mm/37.74+/-10.54 mm at L5. The right multifidus muscle thickness measurements were 32.13+/-10.79 mm/33.84+/-9 mm at L4 and 31.32+/-10.04 mm/32.84+/-12.28 mm at L5. The measuring distance between the spinous process center to the posterior vertebral body surface and thickness of multifidus muscles by ultrasonography and MRI had significant correlations (p<0.05). CONCLUSION: Limitations still exist in measuring the structure of lumbar anatomy with ultrasonography. However, measuring the distance between the spinous process center to the vertebral body posterior surface and multifidus muscle thickness was effective.

Corrigendum: Comparison of Ultrasonography and Magnetic Resonance Imaging in Measurement of Lumbar Spine Anatomic Structures / 대한정형외과학회잡지

This erratum is being published to correct of affiliation and add an acknowledgement.

Comparison between heparin-conjugated fibrin and collagen sponge as bone morphogenetic protein-2 carriers for bone regeneration

Bone morphogenetic protein-2 (BMP-2) is used to promote bone regeneration. However, the bone regeneration ability of BMP-2 relies heavily on the delivery vehicle. Previously, we have developed heparin-conjugated fibrin (HCF), a vehicle for long-term delivery of BMP-2 and demonstrated that long-term delivery of BMP-2 enhanced its osteogenic efficacy as compared to short-term delivery at an equivalent dose. The aim of this study was to compare the bone-forming ability of the BMP-2 delivered by HCF to that delivered by clinically utilized BMP-2 delivery vehicle collagen sponge. An in vitro release profile of BMP-2 showed that HCF released 80% of the loaded BMP-2 within 20 days, whereas collagen sponge released the same amount within the first 6 days. Moreover, the BMP-2 released from the HCF showed significantly higher alkaline phosphatase activity than the BMP-2 released from collagen sponge at 2 weeks in vitro. Various doses of BMP-2 were delivered with HCF or collagen sponge to mouse calvarial defects. Eight weeks after the treatment, bone regeneration was evaluated by computed tomography, histology, and histomorphometric analysis. The dose of BMP-2 delivered by HCF to achieve 100% bone formation in the defects was less than half of the BMP-2 dose delivered by collagen sponge to achieve a similar level of bone formation. Additionally, bone regenerated by the HCF-BMP-2 had higher bone density than bone regenerated by the collagen sponge-BMP-2. These data demonstrate that HCF as a BMP-2 delivery vehicle exerts better osteogenic ability of BMP-2 than collagen sponge, a clinically utilized delivery vehicle.

The Effect of Platelet Rich Plasma from Bone Marrow Aspirate with Added Bone Morphogenetic Protein-2 on the Achilles Tendon-Bone Junction in Rabbits

BACKGROUND: To determine if exogenously injected bone marrow derived platelet-rich plasma (PRP) plus bone morphogenetic protein (BMP)-2 could accelerate the healing of bone-tendon junction injuries and increase the junction holding strength during the early regeneration period. METHODS: A direct injury model of the bone-tendon junction was made using an Achilles tendon-calcaneus bone junction in a rabbit. In the PRP/BMP-2/fibrin group, 0.05 mL of bone marrow derived PRP and 100 ng/mL of BMP-2 both incorporated into 0.1 mL of fibrin glue were injected into Achilles tendon-calcaneus bone junctions. The effect of the intervention was tested by comparing the results of an intervention group to a control group. The results of biomechanical testing, and histological and gross analyses were compared between the 2 groups at the following time points after surgery: 2 weeks, 4 weeks, and 8 weeks. RESULTS: Histologic examinations showed that woven bone developed in tendon-bone junctions at 2 weeks after surgery in the PRP/BMP-2/fibrin group. Mechanical test results showed no significant difference between the PRP/BMP-2/fibrin and control groups at 2 and 4 weeks after surgery, but the mean maximal load in the PRP/BMP-2/fibrin group was significantly higher than in the control group (p < 0.05) at 8 weeks after surgery. CONCLUSIONS: Bone marrow derived PRP and BMP-2 in fibrin glue accelerated healing in a rabbit model of tendon-bone junction injury.

Enhanced skin wound healing by a sustained release of growth factors contained in platelet-rich plasma

Platelet-rich plasma (PRP) contains growth factors that promote tissue regeneration. Previously, we showed that heparin-conjugated fibrin (HCF) exerts the sustained release of growth factors with affinity for heparin. Here, we hypothesize that treatment of skin wound with a mixture of PRP and HCF exerts sustained release of several growth factors contained in PRP and promotes skin wound healing. The release of fibroblast growth factor 2, platelet-derived growth factor-BB, and vascular endothelial growth factor contained in PRP from HCF was sustained for a longer period than those from PRP, calcium-activated PRP (C-PRP), or a mixture of fibrin and PRP (F-PRP). Treatment of full-thickness skin wounds in mice with HCF-PRP resulted in much faster wound closure as well as dermal and epidermal regeneration at day 12 compared to treatment with either C-PRP or F-PRP. Enhanced skin regeneration observed in HCF-PRP group may have been at least partially due to enhanced angiogenesis in the wound beds. Therefore, this method could be useful for skin wound treatment.

Radiation-induced Necrosis Deteriorating Neurological Symptoms and Mimicking Progression of Brain Metastasis after Stereotactic-guided Radiotherapy / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Although radiation-induced necrosis (RIN) is not a tumor in itself, the lesion progressively enlarges with mass effects and diffuse peritumoral edema in a way that resembles neoplasm. To identify the RIN that mimics progression of brain metastasis, we performed surgical resections of symptomatic RIN lesions. Meterials and Methods: From June 2003 to December 2005, 7 patients received stereotactic-guided radiotherapy (SRT) for metastatic brain tumor, and they later underwent craniotomy and tumor resection due to the progressive mass effects and the peritumoral edema that caused focal neurological deficit. On MR imaging, a ring-like enhanced single lesion with massive peritumoral edema could not be distinguished from progression of brain metastasis. RESULTS: Four patients had non-small cell lung cancer, 2 patients had colorectal cancer and 1 patient had renal cell carcinoma. The mean tumor volume was 8.7 ml (range: 3.0~20.7 ml). The prescribed dose of SRT was 30 Gy with 4 fractions for one patient, 18 Gy for two patients and 20 Gy for the other four patients. The four patients who received SRT with a dose of 20 Gy had RIN with or without microscopic residual tumor cells. CONCLUSIONS: Early detection of recurrent disease after radiotherapy and identifying radiation-induced tissue damage are important for delivering adequate treatment. Therefore, specific diagnostic tools that can distinguish RIN from progression of metastatic brain tumor need to be developed.

Strategy for Management of Giant Invasive Pituitary Adenoma

OBJECTIVE: Giant invasive pituitary adenoma looks histologically benign, but these tumors have an aggressive clinical course. The authors review 10 cases and discuss the results obtained and the strategy to use for the management of giant invasive pituitary adenoma. METHODS: Out of a series of 155 pituitary adenomas treated surgically between 1994 and 2002, ten patients with giant invasive pituitary adenoma were selected and their clinical problems, radiologic findings, extent and invasiveness, hormonal and histologic findings and surgical results were analyzed retrospectively. RESULTS: There were 4 male and 6 female patients, with an average age of 47 years and an average follow-up period of 42 months. The average size of tumor was 50.7mm. These tumors revealed severe invasions into surrounding structures. 8 patients underwent transsphenoidal approach(TSA) operations, 1 patient with transcranial operation and 1 patient with combined TSA and transcranial operation. In all cases, subtotal resection was performed. The histologic findings were 2 prolactinomas and 8 hormonal non-function adenomas. The therapies administered after surgical removal consisted of conventional fractionated radiotherapy (2 patients), treatment with dopamine agonists to control hyperprolactinemia (2 patients), and treatment with hormone replacement (2 patients). CONCLUSION: Giant invasive pituitary adenomas are characterized by different forms of expansion and invasiveness and variable clinical problems. Because of their aggressive expansion and invasiveness, there are many different strategies which can be considered for their management. The authors obtain good results by choosing conservative surgical removal and multidisciplinary treatments with serial radiological and hormonal follow-up.

Magnetic Resonance Image Findings of Lumbar Prevertebral Aortocaval Structures in Korean Spinal Disorder Patients

OBJECTIVE: The purpose of this study is to evaluate the level of lumbar spine corresponding to the prevertebral major vascular structures and the distance of the prevertebral available disc space (DPADS) of L5-S1 between the common iliac arteries and veins with preoperative magnetic resonance imaging (MRI) study. METHODS: Three hundred and forty seven lumbar MRI films (200males and 147females) from spinal disorder patients were reviewed. The patients' age ranged 14 to 86 years (mean 45 years). The patients were divided into eight groups by 10-year interval from a teen to the eighties. There were evaluated age-related locational changes in the level of lumbar spine corresponding to the aortic bifurcation (AB) and the origin of inferior vena cava (OIVC). In addition, DPADS of L5-S1 between the common iliac arteries and veins were measured. RESULTS: The common sites of the AB for the entire subject group were at the upper body of L4 (from the upper body of L3 to the lower body of L5). The common sites of the OIVC for the entire subject group were at the level of the L4-L5 disc space (from the upper body of L4 to the lower body of L5). The age-related changes in the location of the AB with a downward shift were statistically significant (p< 0.05). Similarly, age-related changes were observed in the OIVC, although this was more prominent in females (p<0.05). The average DPADS of L5-S1 was 34.48+/-10.00 mm. There were 27 cases(7.8%) who had the DPADS less than 20mm, and this narrow DPADS could make it very difficult to access the anterior disc space of L5-S1 because recently the popularly used anterior lumbar fusion materials were over 10 mm in diameter. CONCLUSION: These results may be helpful to minimize potential vascular injury and morbidity in anterior lumbar spinal surgery.