Biomedical subjects

Ye-Yeon Won

Publications and source records attributed to Ye-Yeon Won.

9 recordsLinked to original sources

PubMed2006

Delayed fracture of a ceramic insert with modern ceramic total hip replacement.

We report a case of ceramic liner fracture in a 34-year-old man that occurred 1 year 9 months after total hip arthroplasty with a BiCONTACT (Aesculap, Tuttlingen, Germany) ceramic-on-ceramic prosthesis. The ceramic liner was found within the metal shell in 4 large pieces and multiple small fragments in the peripheral portions. Its condition indicated that the possible mechanism of late ceramic liner chip fracture was repeated episodes of impingement between the prosthetic neck and the edge of the ceramic liner. Squatting, kneeling, and sitting cross-legged caused impingement. These positions are more common in Asian populations than in Western populations. After the joint was thoroughly irrigated, a new modular ceramic liner and a 28-mm ceramic head were implanted.

Adult↗

PubMed2006

Valgus intertrochanteric osteotomy for non-union of femoral neck fracture.

In spite of improved surgical techniques and fixation devices, non-union still reportedly occurs in 10-30% of cases of femoral neck fracture. A variety of methods of treatment that preserve the femoral head have been described, yet there are few reports on the results of valgus intertrochanteric osteotomy in cases of femoral neck non-union. We treated 11 such cases with valgus intertrochanteric osteotomy performed at one centre and using a single surgical technique. The cases were evaluated clinically and radiographically at a mean of 4.9 years. All of the non-unions were shown radiographically to have healed by an average of 12.5 weeks. Functional outcome was excellent for nine patients and poor for two who underwent subsequent total hip arthroplasty for avascular necrosis of the femoral head. We conclude that valgus intertrochanteric osteotomy is an effective treatment for femoral neck non-union, but avascular necrosis of the femoral head is a possible complication.

Adult↗

PubMed2005

Polyethylene liner failure in second-generation Harris-Galante acetabular components.

Polyethylene liner failure of cementless acetabular components has been reported to be the most common complication of current modular cups. We performed a retrospective review of 128 consecutive primary total hip arthroplasties in 111 patients who had a second-generation Harris-Galante cup (Harris-Galante II, Zimmer, Warsaw, Ind). The mean length of the follow-up period was 8.0 years (range 5-12.9 years), with 26 cups (20.2%) having undergone revision by that time. Twenty-two hips (17.3%) had failure of the polyethylene liner. We found that polyethylene liner failure remains the main cause of revision of this modular cup. The main difference between our population of patients and other populations that have used this cup and liner is our population's cultural inclination toward squatting and leg crossing, body positions that increased the risk of impingement and eccentric wear.

Acetabulum↗

PubMed2004

Maintenance of increased bone mass after recombinant human parathyroid hormone (1-84) with sequential zoledronate treatment in ovariectomized rats.

UNLABELLED: The concept of lose, restore, maintain (LRM) for reversing existing osteoporosis was tested in rats. The withdrawal of PTH results in the loss of the acquired bone mass, but sequential therapy with zoledronate quite effectively maintained the PTH(1-84)-acquired bone quantity and quality. INTRODUCTION: Because antiresorptive agents against osteoporosis are presently quite limited, strong anabolic agents such as human parathyroid hormone (hPTH) are quite helpful. However, because hPTH(1-34) is available only through injection and has a critical side effect of causing bone tumors during life-long administration in the rat, it would be practical to use PTH for the shortest possible duration to obtain the maximal effect. To determine the effectiveness of the osteoporosis-reversing concept of lose, restore, and maintain (LRM), recombinant hPTH(1-84) [rhPTH(1-84)] and the respective antiresorptive agents were sequentially studied. MATERIALS AND METHODS: Thirty-six, 20-week-old Sprague-Dawley rats were used. Treatment started at the 25th week after ovariectomy, which was performed at 20 weeks of age, with 5 weeks of rhPTH(1-84) 100 microg/kg/day, 5 days/week, followed by the respective sequential therapies for 5 weeks as follows: (1) ovariectomized rats (OVX; n = 6), (2) sham-operated rats (SHAM; n = 6), (3) OVX rats with PTH maintenance (PTH-M; n = 6), (4) OVX rats treated with PTH and then PTH was withdrawn (PTH-W; n = 6), (5) PTH-treated OVX rats treated with 17beta-estradiol (PTH-E; 10 microg/day SC, 5 days/week; n = 6), and (6) PTH-treated OVX rats treated with zoledronate (PTH-Z; 12.5 microg/kg SC weekly; n = 6). BMD of the right femora was measured by DXA. microCT was used to measure the structural parameters of the second lumbar vertebrae. Three-point bending test of the femora and compressive tests of vertebrae were also performed. RESULTS: Bone quantity data showed that the BMD and most of the microstructural parameters were significantly higher in the PTH-M and PTH-Z groups than in the OVX and PTH-W groups (p < 0.05). Measurement of the cortical thickness revealed that only the PTH-M group showed a significant increase (p = 0.001). The ultimate force (Fu) at the midshaft of the femora was similar in the treated groups and stronger than in the OVX group (p < 0.05). However, in the vertebrae, the Fu of the PTH-M and PTH-Z groups was significantly higher, by approximately 44-47%, than in the OVX and PTH-E groups and showed a higher tendency than in the PTH-W group. CONCLUSION: PTH withdrawal resulted in the loss of acquired BMD, and sequential therapy with antiresorptives prevented further loss (17beta-estradiol versus zoledronate). The zoledronate after rhPTH(1-84) as a sequential regimen was quite consistently effective.

Absorptiometry, Photon↗

PubMed2004

Assessment of bone graft substitutes in autopsy implant retrievals of the acetabulum in total hip arthroplasty.

Two autopsy retrievals of acetabular reconstruction with different bone graft substitutes were analyzed. One patient underwent surgery with hydroxyapatite (HA) granules, and the other with demineralized bone chips. Incorporation occurred with the biomaterial bone-graft substitute HA primarily in the superior part of the acetabulum, where the HA was in contact with host cortical bone. No bony union occurred with the demineralized bone chips because of motion and migration of the acetabular cup. No bone incorporation of either bone-graft substitute was observed in the medial wall defects in both patients. There were two important findings: (1) the 3- to 8-mm depth and 70% to 75% surface of union of the HA bone graft substitute to host cortical bone was the same as seen with morselized, fresh-frozen bone graft; and (2) union of graft material to host bone was dependent on secure fixation of the acetabular construct.

Acetabulum↗

PubMed2004

Pseudoaneurysm after tibial nailing.

This is a case report of a patient with a pseudoaneurysm of the anterior tibial artery after lateral to medial distal locking of an intramedullary nail for a tibia shaft fracture.

Aneurysm, False↗

PubMed2004

Comparison of proximal porous-coated and grit-blasted surfaces of hydroxyapatite-coated stems.

BACKGROUND: It remains controversial whether a proximal porous coating is superior to a grit-blasted surface with regard to providing femoral stem fixation in total hip arthroplasty. We examined the hypothesis that a proximal porous coating would provide better fixation than would a fully grit-blasted surface of otherwise identical proximally hydroxyapatite-coated stems. METHODS: In a prospective study, seventeen patients (thirty-four hips) underwent bilateral sequential total hip replacement with the Anatomic Porous Replacement at the same operation. A proximally porous-coated femoral stem was implanted on one side, and a stem of the same design but with a proximal grit-blasted surface was implanted in the contralateral hip. A proximal hydroxyapatite coating was applied to the metallic substrate of both stems. The patients were followed for a mean 2.5 years and then were assessed radiographically and clinically with the Harris hip score. RESULTS: With the numbers available, no significant clinical or radiographic differences were found between the two cohorts. Thirty of the thirty-four hips had an excellent result, two were rated good, and two were rated fair. All hips had stable osseous fixation of the stem radiographically. The two types of stems were associated with the same pattern of adaptive bone-remodeling. CONCLUSIONS: In the first two years following total hip arthroplasty, hydroxyapatite-coated proximally porous-coated femoral stems do not provide fixation that is superior to that provided by hydroxyapatite-coated grit-blasted stems. LEVEL OF EVIDENCE: Therapeutic study, Level II-1 (prospective cohort study). See Instructions to Authors for a complete description of levels of evidence.

Adult↗

PubMed2003

Correlations between microcomputed tomography and bone histomorphometry in Korean young females.

The bone mass and microarchitecture are important determinants of bone strength, with microarchitectural deterioration being one of the specific changes associated with osteoporosis. The purpose of this study was to evaluate and compare the results of microcomputed tomography (micro-CT) and histomorphometry of biopsied specimens. A bone biopsy was performed on the iliac crest of 10 normal premenopausal Korean women. Measurements of the bone mineral density (BMD), micro-CT, and bone histomorphometry were performed. The bone volume, as determined by both micro-CT and histomorphometry, was significantly correlated (r=0.88, p < 0.01). The osteoid surface was correlated with both the bone volume (r=0.84, p < 0.01) and the structure model index (SMI) (r= -0.89, p < 0.01) measured by micro-CT. The SMI was correlated with both the bone volume (r=-0.85, p < 0.01) and the total hip BMD (r=-0.65, p < 0.05). In conclusion, some, but not all of the parameters of the micro-CT, were well correlated with the bone histomorphometric results. Micro-CT and histomorphometry appear to be complementary techniques in the study of bone microarchitecture.

Adult↗

PubMed2003

Morphological study on the acetabular labrum.

For the diagnosis and treatment of the labral pathology, the cross sectional morphology of the labrum is needed. Fifty-four labra (male:female=44:10) from 32 adult Korean cadavers were cut in radial and perpendicular fashions to their longitudinal axis. Each labrum was divided into 8 segments, resulting 8 equally distanced points. To analyze the 432 cut surfaces, which consisted of 378 labra and 54 transverse acetabular ligaments cut surfaces, all dimensions of the cut surfaces were measured, and the attachment patterns, including the sublabral slit, observed. The shapes of the cut surfaces were classified into four types (3 subtypes of triangle and 1 quadrangle) and the attachment patterns into five types. At the anterior portion of the labrum, which other studies reported as the predilection area for labral tears, there were several common findings: 1) Tall triangular shapes were dominant (61.1%) or relatively common type (25.9%). 2) The average heights of the labrum were longer (7.4 and 7.0 mm) than at the other sites (4.0 - 6.8 mm). 3) The attachment types with no extra-extended portion (68.5%) and sublabral slits (39.0%) were most commonly observed. It was concluded that there were different types of cut surface and attachment patterns of the acetabular labrum, and these findings had a tendency to be distributed with some labral tears. These anatomical data are believed could be useful in the management of an acetabular labral pathology.

Acetabulum↗