• Advances in biomechanics and applications
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• 제1권3호
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• pp.169-185
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• 2014

Computational multibody models of the elbow can provide a versatile tool to study joint mechanics, cartilage loading, ligament function and the effects of joint trauma and orthopaedic repair. An efficiently developed computational model can assist surgeons and other investigators in the design and evaluation of treatments for elbow injuries, and contribute to improvements in patient care. The purpose of this study was to develop an anatomically correct elbow joint model and validate the model against experimental data. The elbow model was constrained by multiple bundles of non-linear ligaments, three-dimensional deformable contacts between articulating geometries, and applied external loads. The developed anatomical computational models of the joint can then be incorporated into neuro-musculoskeletal models within a multibody framework. In the approach presented here, volume images of two cadaver elbows were generated by computed tomography (CT) and one elbow by magnetic resonance imaging (MRI) to construct the three-dimensional bone geometries for the model. The ligaments and triceps tendon were represented with non-linear spring-damper elements as a function of stiffness, ligament length and ligament zero-load length. Articular cartilage was represented as uniform thickness solids that allowed prediction of compliant contact forces. As a final step, the subject specific model was validated by comparing predicted kinematics and triceps tendon forces to experimentally obtained data of the identically loaded cadaver elbow. The maximum root mean square (RMS) error between the predicted and measured kinematics during the complete testing cycle was 4.9 mm medial-lateral translational of the radius relative to the humerus (for Specimen 2 in this study) and 5.30 internal-external rotation of the radius relative to the humerus (for Specimen 3 in this study). The maximum RMS error for triceps tendon force was 7.6 N (for Specimen 3).

• Clinics in Shoulder and Elbow
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• 제20권1호
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• pp.30-36
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• 2017

Background: Isolated infraspinatus tear is very rare and clinical features are not as well known, therefore the purpose of this study was to evaluate clinical characteristics and outcomes of isolated infraspinatus tear that authors experienced. Methods: Authors reviewed 288 cases of full-thickness rotator cuff tear involving infraspinatus between 2010 and 2015, and retrospectively analyzed six cases of isolated infraspinatus tear. Perioperative clinical characteristics, postoperative functional outcomes of 6 months were investigated. Functional evaluation included visual analogue scale (VAS), range of motions, American Shoulder and Elbow Surgeons (ASES) score, and Constant score. Results: Calcific tendinitis was accompanied in 4 cases (66.7%). Three of them received steroid injection or aspiration or extracorporeal shockwave therapy. Mean preoperative pain VAS was 7.1 (range, 5-9), and mean postoperative pain VAS at 6 months later was 1.6 (range, 0-5). Preoperative muscle strength by isokinetic muscle performance test showed 52% deficit of abduction and 37.6% deficit of external rotation. All 6 patients had arthroscopic repair of the infraspinatus tendon. All the patients at the 6 months follow-up exhibited clinical improvement in the Constant score (67.8 [range, 45-77] to 89.3 [range, 81-100], p=0.029), and ASES score (52.3 [range, 30-77] to 90.0 [range, 80-100], p=0.002). There was no healing failure on imaging. Conclusions: Isolated infraspinatus tendon tear was frequently accompanied by calcific tendinitis, but pathophysiologic relationship should need more study. To rule out neurogenic etiology, magnetic resonance imaging and electromyography would be helpful. Arthroscopic infraspinatus tendon repair and supraspinatus debridement showed relatively good result in painful shoulder.

• Clinics in Shoulder and Elbow
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• 제21권4호
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• pp.207-212
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• 2018

Background: Delaminated rotator cuff tear is known to be a degenerative tear having a negative prognostic effect. This study undertook to compare the anatomical and clinical outcomes of delaminated tears and single layer tears. Methods: Totally, 175 patients with medium to large rotator cuff tears enrolled for the study were divided into 2 groups, based on the tear pathology: single layer tear (group 1) and delaminated tear (group 2). Preoperatively, length of the remnant tendon, muscle atrophy of supraspinatus (SS), and fatty degeneration of SS and infraspinatus (IS) muscles were assessed on magnetic resonance imaging (MRI). For follow-up, the repair integrity of the rotator cuff was evaluated by ultrasonography. Clinical outcomes were assessed by evaluating the Constant score (CS) and Korean Shoulder Score (KSS). Results: Retears were detected in 6 cases of group 1 (6.5%) and 11 cases of group 2 (13.3%). Although higher in group 2, the retear rate was significantly not different (p=0.133). Preoperative MRI revealed length of remnant tendon to be $15.46{\pm}3.60mm$ and $14.17{\pm}3.16mm$ (p=0.013), and muscle atrophy of SS (occupation ratio) was $60.54{\pm}13.15$ and $56.55{\pm}12.88$ (p=0.045), in group 1 and group 2, respectively. Fatty degeneration of SS and IS in both groups had no significant differences. Postoperatively, no significant differences were observed for CS and KSS values between the groups. Conclusions: Delaminated rotator cuff tears showed shorter remnant tendon length and higher muscle atrophy that correlate to a negative prognosis. These prognostic effects should be considered during delaminated rotator cuff tear treatment.

• 대한영상의학회지
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• 제82권6호
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• pp.1388-1401
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• 2021

회전근개(rotator cuff) 수술 후 영상은 통증이나 장애가 수술 후 새로 발생하거나 혹은 증상이 없어도 일상적으로 시행된다. 수술 후 영상은 MRI나 초음파 등을 통해 얻으며 일반적으로 복구된 힘줄(건)의 완전성을 확인하고자 하는 것이 목적이다. MRI는 술 후 해부학적 구조 변경을 전반적으로 확인할 수 있고 수술 후 합병증 등을 객관적으로 확인할 수 있지만 여러가지 수술에 사용된 물질들이 화질을 나쁘게 하여 술 전 영상에 비하여 진단 정확도가 떨어진다. 초음파는 복구된 회전근개의 상태를 역동적으로 확인할 수 있고 회복에 사용되는 수술기구들로부터 생기는 인공물도 피할 수 있다. 영상 소견이 항상 임상 증상이나 예후와 일치하지는 않으나 재건된 건의 두께보다는 삼각근하 액체 저류가 통증과 기능 회복에 있어 중요하다. 긴장 탄성도 검사도 예후를 예측하는데 유용한 방법이 될 수 있다.

• Investigative Magnetic Resonance Imaging
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• 제18권3호
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• pp.225-231
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• 2014

목적: 슬관절에서 대퇴이두건과 외측 측부인대는 병합건을 형성하여 비골에 붙는다고 알려져있다. 그러나 대퇴이두건과 외측 측부인대는 여러 형태로 비골두에 붙는다. 우리는 자기공명영상을 이용하여 대퇴이두건과 외측 측부인대의 부착 형태를 분류하였고 외측 측부인대가 비골두에 붙는지 여부를 분석하였다. 대상과 방법: 2012년 7월부터 2012년 12월 사이에 슬관절 자기공명영상을 촬영한 470명의 환자의 총 494개의 자기공명영상을 후향적으로 평가하였다. 224명의 남자, 246명의 여자가 포함되었으며 나이는 10세에서 88세(평균, 48.6세) 범위였다. 배제기준은 이전의 수술을 받거나 영상질이 나쁜 경우였다. 3T 지방억제 수소밀도 강조영상을 이용하여 대퇴이두건과 외측 측부인대의 비골부착 형태를 다음과 같이 분류하였다: 유형 I (외측 측부인대가 대퇴이두건 장골의 전방팔과 직접팔 사이로 지나간다), 유형 II (외측 측부인대가 대퇴이두건 장골의 전방팔과 합쳐진다), 유형 III (대퇴이두건과 외측 측부인대가 병합건을 형성한다), 유형 IV (외측 측부인대가 대퇴이두건의 전방으로 돌아 외측으로 지나간다), 유형 V (외측측부인대가 대퇴이두건 장골의 직접팔의 후방으로 지나간다). 결과: 슬관절 자기공명영상의 494 증례 가운데, 유형 I이 433 (87.65%)예, 유형 II가 21 (4.25%)예, 유형 III이 2 (0.4%)예, 유형 IV가 16 (3.23%)예, 유형 V가 22 (4.45%)예 였다. 대퇴이두건과 외측 측부인대가 비골두에 붙지않는 경우는 26 (5.26%)예 였다. 결론: 대퇴이두건과 외측 측부인대의 비골두 부착은 자기공명영상에서 다양한 형태를보인다. 외측 측부인대는 어떤 환자에서는 비골두에 부착하지 않는다.

• Journal of Korean Neurosurgical Society
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• 제48권2호
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• pp.153-156
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• 2010

The authors present a rare case of clear cell ependymoma that developed in the cauda equina. A 54-year-old man was admitted to hospital with intermittent lower back pain. A neurological examination conducted on admission revealed no sensory or motor disturbance. Deep tendon reflexes in both lower extremities were normal. Magnetic resonance images demonstrated a 1.0 cm-sized intradural mass at the filum terminale. Gross total resection was performed via total laminectomy of L1 and L2. The tumor was confirmed to be clear cell ependymoma by histopathologic examination. His symptom was relieved after surgery.

• Clinics in Shoulder and Elbow
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• 제19권4호
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• pp.237-240
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• 2016

Retear patterns after arthroscopic rotator cuff repair are classified into two patterns according to retear location. Type 1 is when the retear pattern occurs directly on the tendon at the bone repair site using the suture anchor repair method. Type 2 is when the retear pattern occurs at the musculocutaneous junction with a healed footprint in patients who undergo the suture bridge method. Here, the authors report another retear pattern, which was identified as a type 2 retear on magnetic resonance imaging in patients who had undergone arthroscopic rotator cuff repair by the suture-bridge technique. This pattern was different from the type 2 retear and occurred at the portion of the cuff away from the healed rotator cuff under the view of the arthroscope.

• The Korean Journal of Pain
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• 제24권2호
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• pp.69-73
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• 2011

Although the incidence of partial-thickness rotator cuff tears (PTRCTs) was reported to be from 13% to 32% in cadaveric studies, the actual incidence is not yet known. The causes of PTRCTs can be explained by either extrinsic or intrinsic theories. Studies suggest that intrinsic degeneration within the rotator cuff is the principal factor in the pathogenesis of rotator cuff tears. Extrinsic causes include subacromial impingement, acute traumatic events, and repetitive microtrauma. However, acromially initiated rotator cuff pathology does not occur and extrinsic impingement does not cause pathology on the articular side of the tendon. An arthroscopic classification system has been developed based on the location and depth of the tear. These include the articular, bursal, and intratendinous areas. Both ultrasound and magnetic resonance image are reported with a high accuracy of 87%. Conservative treatment, such as subacromial or intra-articular injections and suprascapular nerve block with or without block of the articular branches of the circumflex nerve, should be considered prior to operative treatment for PTRCTs.

• 고신대학교 의과대학 학술지
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• 제33권2호
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• pp.257-262
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• 2018

Guillain-$Barr{\acute{e}}$ syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) are demyelinating neurologic disorders with different target organs. Although they share similar pathogenetic mechanism, reports of simultaneous occurrence of the 2 disorders are rare. A 2 year 6 month old girl visited our hospital for fever, cough, and general weakness. Although the muscle power of extremities showed mild weakness and voiding difficulty, initial deep tendon reflex of both knees and ankles was normal. A nerve conduction study to evaluate the weakness revealed the absence of F waves. Cerebrospinal fluid analysis demonstrated pleocytosis with lymphocyte predominance and elevated protein levels. Magnetic resonance imaging showed abnormal T2 hyperintensity in pons, medulla and spinal cord. Serum anti-GD1b antibody was positive. Based on clinical findings, laboratory findings, nerve conduction study, and neuroimaging, the diagnosis of GBS and ADEM was made. This is the first case of GBS accompanied by ADEM in Korea.

• Clinics in Shoulder and Elbow
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• 제26권3호
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• pp.330-339
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• 2023

Rupture of the pectoralis major muscle typically occurs in the young, active male. Acute management of these injuries is recommended; however, what if the patient presents with a chronic tear of the pectoralis major? Physical exams and magnetic resonance imaging can help identify the injury and guide the physician with a plan for management. Nonoperative management is feasible, but is recommended for elderly, low-demand patients whose functional goals are minimal. Repair of chronic tears should be reserved for younger, healthier patients with high functional demands. Although operative management provides better functional outcomes, operative treatment of chronic pectoralis tears can be challenging. Tendon retraction, poor tendinous substance and quality of tissue, muscle atrophy, scar formation, and altered anatomy make direct repairs complicated, often necessitating auto- or allograft use. We review the various graft options and fixation methods that can be used when treating patients with chronic pectoralis major tears.