• Journal of Korean Neurosurgical Society
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• 제66권4호
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• pp.476-481
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• 2023

Objective : The latest version of the Leksell Gamma Knife Icon^TM allows for mask- and frame-based fixation. Although mask fixation provides fractionated treatment and immobilization using a noninvasive method, it is not free from collision. The authors investigated the collision problem with a modified mask fixation method. Methods : This study presents a case of two meningiomas in the frontal area, where a collision occurs in the occipital area. A modified mask fixation method was introduced to avoid the collision : first, the edges of the head cushion were cut off and polystyrene beads with a diameter of approximately 5 cm were removed. Next, the head cushion was sealed using a stapler. Finally, the head cushion was flattened in the adapter. We compared the shot coordinates, 3-dimensional (3D) error, clearance distance, and vertical depth of the head cushion between the initial and modified mask fixations. Results : When comparing the initial and modified mask fixations, the difference in the shot coordinates was +10.5 mm along the y-axis, the difference in the 3D error was approximately 18 mm, and the difference in clearance was -10.2 mm. The head cushion was approximately 8 mm deeper in the modified mask fixation. Conclusion : Based on these findings, we recommend a modified mask fixation method for gamma knife radiosurgery using ICON with a collision.

• The Korean Journal of Physiology and Pharmacology
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• 제18권2호
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• pp.103-108
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• 2014

Head restraining is an experimental technique that firmly secures the animal's head to a fixation apparatus for the precise control and sensing of behaviors. However, procedural and surgical difficulties and limitations have been obstructing the use of the technique in neurophysiological and behavioral experiments. Here, we propose a novel design of the head-restraining apparatus which is easy to develop and convenient for practical use. Head restraining procedure can be completed by sliding the head mounter, which is molded by dental cement during implantation surgery, into the port, which serves as matching guide rails for the mounter, of the fixation bar. So neither skull-attached plates nor screws for fixation are needed. We performed intracranial self stimulation experiment in rats using the newly designed device. Rats were habituated to acclimatize the head-restraint environment and trained to discriminate two spatially distinguished cues using a customized push-pull lever as an operandum. Direct electrical stimulation into the medial forebrain bundle served as reward. We confirmed that head restraining was stable throughout experiments and rats were able to learn to manipulate the lever after successful habituation. Our experimental framework might help precise control or sensing of behavior under head fixed rats using direct electrical brain stimulation as a reward.

• The Journal of Korean Physical Therapy
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• 제35권4호
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• pp.117-123
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• 2023

Purpose: In this study, subjects with femoral anterior glide type were examined to investigate the effects of femoral head anterior glide fixation during active straight leg raise on the strength of the hip flexor in a supine position. Methods: Fifteen subjects participated in this study. All subjects were classified through an evaluation form for femoral anterior glide type (FAGT). The strength of the hip flexor was measured during active straight leg raise test (ASLR test), and compared with and without femoral anterior glide fixation in a supine position. The fixation of the femoral head was achieved as per the therapist's manual guidelines. Paired t-test was applied to compare changes in the strength of the hip flexor according to fixation conditions. The level of statistical significance was set at α=0.05. Results: The strength of the hip flexor was lesser during the ASLR test with fixation compared to without fixation (p=0.007). Conclusion: The strength of the hip flexor decreases with fixation. Results of this study revealed a difference between hip flexor strength, with and without femoral anterior glide fixation during ASLR, in subjects with femoral anterior glide type.

• 대한치과교정학회지
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• 제43권6호
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• pp.263-270
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• 2013

Objective: To evaluate condylar head remodeling after mandibular set-back sagittal split ramus osteotomy (SSRO) with rigid fixation in skeletal class III deformities. The correlation between condylar head remodeling and condylar axis changes was determined using cone-beam computed tomography (CBCT) superimposition. Methods: The CBCT data of 22 subjects (9 men and 13 women) who had undergone mandibular set-back SSRO with rigid fixation were analyzed. Changes in the condylar head measurements and the distribution of the signs of condylar head remodeling were evaluated by CBCT superimposition. Results: The subjects showed inward rotation of the axial condylar angle; reduced condylar heights on the sagittal and coronal planes; and resorptive remodeling in the anterior and superior areas on the sagittal plane, superior and lateral areas on the coronal plane, and anterior-middle and anterior-lateral areas on the axial plane (p < 0.05). Conclusions: The CBCT superimposition method showed condylar head remodeling after mandibular set-back SSRO with rigid fixation. In skeletal class III patients, SSRO with rigid fixation resulted in rotation, diminution, and remodeling of the condylar head. However, these changes did not produce clinical signs or symptoms of temporomandibular disorders.

• Clinics in Shoulder and Elbow
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• 제20권4호
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• pp.236-239
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• 2017

After dual plating with a locking compression plate for comminuted intraarticular fractures of the distal humerus, the incidence of ulnar nerve injury after surgery has been reported to be up to 38%. This can be reduced by an anterior transposition of the ulnar nerve but some surgeons believe that extensive handling of the nerve with transposition can increase the risk of an ulnar nerve dysfunction. This paper reports ulnar nerve injuries caused by the incomplete insertion of a screw head in dual plating without an anterior ulnar nerve transposition for AO/OTA type C2 distal humerus fractures. When an anatomical locking plate is applied to a distal humeral fracture, locking screws around the ulnar nerve should be inserted fully without protrusion of the screw because an incompletely inserted screw can cause irritation or injury to the ulnar nerve because the screw head in the locking system usually has a slightly sharp edge because screw head has threads. If the change in insertion angle and resulting protruded head of the screw are unavoidable for firm fixation of fracture, the anterior transposition of the ulnar nerve is recommended over a soft tissue shield.

• 대한족부족관절학회지
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• 제18권2호
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• pp.76-79
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• 2014

In treatment of failure in ankle joint replacement therapy, talar avascular necrosis with massive bone defect, talus fracture with severe comminution and bone defect and ankle dislocation, treatment of large bone defects is considerably important for ankle joint stability and union, therefore, the choice of treatment for large bone defects is use of femoral head or iliac crest bone graft and rigid internal fixation. Because first generation total ankle arthroplasty performed for the first time using a cemented fixation technique requires a large amount of bone resection during re-surgery and there is some possibility of a larger bone defect after removal of implants, in cases where prosthesis for the defect is needed, performance of palliative femoral head or iliac crest bone graft and rigid internal fixation can be difficult. We report on a case of a 48-year-old woman who had experienced ankle pain for 25 years since undergoing total ankle arthroplasty. Because the patient had little ankle motion and rigid soft tissue despite a large bone defect caused by aseptic loosening, a good outcome was obtained only for the femoral cancellous bone graft using allo femoral head without internal fixation.

• Journal of Trauma and Injury
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• 제28권2호
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• pp.55-59
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• 2015

Purpose: To compare clinical and radiographic outcomes of between two and three Kirschner wire(K-wire) intramedullary fixation for fractures in the neck of the metacarpal bone. Methods: A single institutional retrospective review identified 28 cases of metacarpal fractures between March 2010 and August 2014. Each of the cases met the inclusion criteria for closed, extra-articular fractures of the neck of the metacarpal bone. The patient groups were divided by the number of K-wire. Outcomes were compared for range of motion of the metacarpophalangeal joint, radiographic parameters, and period until union. Results: The fractures were treated with either 2 Kirschner wire fixation (n=10) or 3 Kirschner wire fixation (n=18). The active range of motion of metacarpophalangeal joint and radiographic result showed no statistically significant difference between the two groups. The mean union period was 5.9 weeks. However, four cases suffered distal head perforation in 2 K-wire fixation group and one case in 3 K-wire fixation group. Conclusion: Multiple retrograde intramedullary Kirschner wire fixation is a good treatment of choice for fractures in the neck of the metacarpal bone. To prevent metacarpal head perforation, it is preferred to use three K-wires than two K-wires.

• 대한정형외과스포츠의학회지
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• 제5권1호
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• pp.75-80
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• 2006

목적: 해부학적 정복이 가능한 요골두 골절에 대하여 Acutrak 나사를 이용한 고정술의 치료 결과와 유용성에 대해 알아보고자 하였다. 대상 및 방법: 2001 년 5월부터 2003년 2월까지 본원에서 요골두 골절에 대해 수술한 12 예중 Acutrak 나사 고정술로 치료한 7 예를 대상으로 하였다. 추시 기간은 최소 6개월부터 최장 30개월로 평균 1.2년이었고, 평균 나이는 47세였다 손상의 원인은 낙상이 4예, 교통사고가 3예이었다. 치료 결과 평가 방법은 Mayo Clinic에서 발표한 Functional Rating index를 이용하였다 결과: Mayo Clinic의 Functional Rating Index를 이용한 기능적 평가상 우수가 2예, 양호가 5예였다 방사선학적 소견 상 모든 예에서 골유합 소견을 보였고, 부정 유합이나 나사 이완, 이소성 골형성, 감염, 외상 후 퇴행성 변화 등의 합병증은 없었고 수술 후 건측과 비교하여 운동장애도 보이지 않았다. 결론: 본원에서 시행한 요골두 골절의 Acutrak 나사 고정은 요골두 부분의 안전지대에 대한 고려없이 시행 가능하며 방사선학적 및 임상적 평가에서 만족할 만한 결과를 보였고, Acutrak 나사의 형태학적 특성상 골절의 선상 형태에 대하여 근위 요척골관절에 영향을 주지 않으며, 강한 고정력을 얻을 수 있는 술식으로 사료된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권5호
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• pp.382-387
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• 2021

Objectives: Zygomatic complex (ZMC) fractures comprise up to 40% of all facial fractures. Misaligned bone fragments and misplaced fixation hardware traditionally detected postoperatively on plain radiographs of the skull might require re-operation. The intraoperative O-Arm (Medtronic, USA) is a three-dimensional (3D) computed tomographic imaging system. Materials and Methods: This retrospective single-center study evaluated the utility of O-Arm scanning during corrective surgeries for ZMC and zygomatic arch (ZA) fractures from 2018 to 2020. Three females and 16 males (mean age, 31.52 years; range, 22-48 years) were included. Fracture instability (n=6) and facial deformity (n=15) were the most frequent indications for intraoperative 3D O-Arm scan. Results: The images demonstrated that all fracture lines were properly reduced and fixed. Another scan performed at the end of the fixation or reduction stage, however, revealed suboptimal results in five of the 19 cases, and further reduction and fixation of the fracture lines were required. Conclusion: Implementation of an intraoperative O-Arm system in ZMC and ZA fracture surgeries assists in obtaining predictable and accurate results and obviates the need for revision surgeries. The device should be considered for precise operations such as ZMC fracture repairs.

• 대한족부족관절학회지
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• 제13권1호
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• pp.91-94
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• 2009

Metatarsal head and neck fractures are injuries that often result from a direct blow of a heavy objects to the metatarsal head. The head is often impacted or displaced to the plantar aspect that if not treated may cause malunion which later induces painful plantar calluses. If the fracture fragment is large enough, closed reduction may be successfully performed, but when the fragment is small or closed reduction is unsuccessful, open reduction is needed. We present our reduction and fixation technique for the metatarsal head and neck fractures using antegrade intramedullary Kirschner wire (K-wire) without opening the fracture site or infringing the metatarsophalangeal (MTP) joint which allows immediate motion of the joint and partial weight bearing in a stiff soled shoe.