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The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 1 | Pages 32 - 36
1 Jan 2012
Nho J Lee Y Kim HJ Ha Y Suh Y Koo K

A variety of radiological methods of measuring version of the acetabular component after total hip replacement (THR) have been described. The aim of this study was to evaluate the reliability and validity of six methods (those of Lewinnek; Widmer; Hassan et al; Ackland, Bourne and Uhthoff; Liaw et al; and Woo and Morrey) that are currently in use. In 36 consecutive patients who underwent THR, version of the acetabular component was measured by three independent examiners on plain radiographs using these six methods and compared with measurements using CT scans. The intra- and interobserver reliabilities of each measurement were estimated. All measurements on both radiographs and CT scans had excellent intra- and interobserver reliability and the results from each of the six methods correlated well with the CT measurements. However, measurements made using the methods of Widmer and of Ackland, Bourne and Uhthoff were significantly different from the CT measurements (both p < 0.001), whereas measurements made using the remaining four methods were similar to the CT measurements. With regard to reliability and convergent validity, we recommend the use of the methods described by Lewinnek, Hassan et al, Liaw et al and Woo and Morrey for measurement of version of the acetabular component.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 88 - 88
1 Mar 2010
KIM Y YOO JJ YOON KS KOO K LEE Y KWON YS KIM HJ
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Background: Ceramic-on-ceramic couplings are an attractive alternative bearing surfaces to eliminate or reduce problems related to polyethylene wear debris. Past disappointing experiences with alumina ceramic bearings have led to many improvements in the manufacture and the design of ceramic implants. The purpose of this study was to report the results of contemporary alumina-on-alumina total hip arthroplasties (THAs) with regard to wear, osteolysis, and fracture of the ceramic after a 10-year minimum follow-up.

Methods: We evaluated the results of a series of 66 primary alumina-on-alumina THAs with a metal-backed socket and a cementless stem in 59 patients. All of the patients were 64 years old or younger (mean, 42 years), and a single surgeon performed all of the procedures. They were evaluated clinically and radiographically at the 120 to 126 months follow-up (average, 123 months). During the follow-up, special regards were addressed to wear, periprosthetic osteolysis and ceramic failure.

Results: During the follow-up period, two patients (two hips) had died with the prosthesis in situ as the result of an unrelated medical condition. The mean Harris hip score was 94 points at the latest follow-up evaluation. All of the prostheses had radiographic evidence of a bone ingrowth. No implant was loosened radiographically and no implant was revised. Ceramic wear was not detectable in the 28 hips where differentiation of the femoral head from the cup was possible on radiographs. Periprosthetic osteolysis was observed in no hip. A fracture of the alumina femoral head and a peripheral chip fracture of the alumina insert occurred in one hip following a major motor vehicle accident. A periprosthetic femoral fracture, which required open reduction and internal fixation with metal cables, had occurred in one hip. This fracture healed without problem.

Conclusion: The results of contemporary alumina-on-alumina THAs with a metal-backed socket and a cementless stem were encouraging after a minimum follow up of 10 years. We believe that these improved alumina-on-alumina bearing implants offer a promising option for younger active patients.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 74 - 74
1 Mar 2010
Breitbart E Meade S Yeh S Al-Zube L Azad V Lee Y Livingston-Arinzehand T Lin S
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Introduction/Background: Diabetes Mellitus (DM) is a disease affecting over 21 million Americans resulting in numerous systemic effects, one of which is impaired bone healing. This study was designed to determine the osteoinductive capacity of MSC augmentation in allograft incorporation within a critical size femoral defect model in rats with DM.

Materials/Methods: A 5mm critical size defect was created in the right femur of 40 male DM BB Wistar. Groups: DM/Allograft(All)+DBM and Non-DM/All+DBM: In two groups, the defect was filled with an allograft from a normal non-DM donor rat filled with approximately 0.05mm3 of DBM. DM/All+DBM/MSCs: In the experimental group, the defect was filled with All+DBM, and loaded with 10×106 MSC/mL. Histomorphometry: Animals were sacrificed at 4 and 8 weeks post-surgery, the femurs were processed for undecalcified histomorphometry, and seven areas of interest were measured.

Results: At 4 and 8 weeks the average bone formation within the defect and total bone formation in the DM/All+DBM/MSC group and at 8 weeks the average total bone formation in the Non-DM/All+DBM group was significantly increased compared to the DM/All+DBM group. No significance was found comparing the Non-DM/All+DBM and DM/All+DBM/MSC groups.

Discussion/Conclusions: This study reveals decreased amount of new bone formation in DM animals compared to Non-DM animals, showing the detrimental effects of DM upon allograft incorporation in a critical size defect. MSC augmentation resulted in new bone formation in DM animals similar to Non-DM animals, suggesting a potential role for MSC as an advjuvant during the process of allograft incorporation.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 118 - 119
1 Mar 2010
Lee K Young K Lee Y Kim J Park S Kim D
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Recently with the introduction of operations using various instrument of total ankle arthroplasty, we are showing quite satisfactory short term results on the treatment of resolved pain of ankle joint. However, there have been reports of high probability of complication from total ankle arthroplasty to other arthroplasty applied to other joints. Therefore in order to make the results of ankle arthroplasty superior, it is necessary to reduce these complications. We try to analyze complications that occur often and come up with the best results.

There were 45 cases of 42 patients of HINTEGRA® (Newdeal SA, Lyon, France) model from November 2004 to August 2006. Follow up averaged 33.5 months, the average age of patients was 61.1 years, with 14 males and 28 females. We evaluated the complications and analyzed the causes of failures. There was a total 15 cases of complications; 5 cases of medical impingement syndrome, 3 cases of varus malposition, 2 cases of delayed healing of wound, 1 case of peroneal nerve problem, medial malleolar fracture, postoperative deep infection and gouty arthritis pain and Achilles tendinitis.

Our conclusion is that total ankle arthroplasty had more complication rate than other joint arthroplasty, so we need a more meticulous preoperative and perioperative care.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_III | Pages 455 - 455
1 Sep 2009
Bistolfi A Bracco P Lee Y Crova M Thornhill T Bellare A
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The performance of ultra-high molecular weight polyethylene (UHMWPE) used in total joint replacement prosthesis depends on its wear resistance, oxidation resistance and mechanical properties. Several studies have now established that radiation crosslinking by applying a dose of 50–100 kGy gamma or electron beam radiation followed by remelting to quench free radicals fulfils the criterion of high wear resistance as well as oxidation resistance. However, post-irradiation remelting leads to a decrease in several mechanical properties of UHMWPE including fracture toughness and resistance to fatigue crack propagation, which are deemed important for components in joints where they are subjected to high stresses, such as in tibial components.

In this study, we used uniaxial compression and high-pressure crystallization to disentangle UHMWPE, expecting that this would assist in increasing its crystallinity since disentangled polymer chains would be more readily incorporated into crystalline lamellae, thereby increasing overall crystallinity. This could then result in an increase in some mechanical properties of irradiated, remelted UHMWPE since high crystallinity is associated with high modulus and yield stress. Uniaxial compression of irradiated, remelted GUR 1050 UHMWPE at 130C to a compression ratio up to 2.5 followed by remelting to recover crystallographic orientation showed no statistically significant increase in crystallinity (p> 0.05, ANOVA). High-pressure crystallization at 500 MPa and temperatures in a range of 130-220C also did not show statistically significant increase in crystallinity of irradiated, remelted UHMWPE. However high-pressure crystallization at 500MPa pressure and 240C, where crystallization occurs via the hexagonal phase, increased the crystallinity from 46.2% to 56.4% (p< 0.05, ANOVA).

We conclude that high-pressure crystallization via the hexagonal phase is more effective than uniaxial compression followed by strain recovery or high-pressure crystallization via the orthorhombic phase in increasing the crystallinity of irradiated, remelted UHMWPE, with potential to recover some mechanical properties.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 214 - 214
1 Nov 2002
Lee Y Hui JH Loke K Lee E Hui H
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Objective: To determine the efficacy and safety of pamidronate combined with intramedullary rodding in improving bone mineralisation and reducing fracture incidence in children with osteogenesis imperfecta (O.I.).

Methods: A prospective pilot, open study was performed in which intravenous pamidronate was administered at 1.5 mg/kg bi-monthly to 12 children with O.I., over 18 – 28 months. The children were serially monitored for symptoms, anthropometric measurements, fracture incidence, biochemical assessments of calcium metabolism, bone mineral density (BMD), serum alkaline phosphatase (ALP), urinary N-telopeptides, and spine X-rays. Intra-medullary rodding of fractures were performed with when there was definite angulation of bones.

Results: The number of fractures decreased from 4 to 0.85 fractures/year during pamidronate therapy (p< 0.05). After 18 months of treatment, there was significant improvement in Areal BMD z scores of the lumbar spine from −2.38 to −1.76 (p < 0.05) and in the Volumetric BMD, which increased from 0.06 to 0.09 g/cm3 (p < 0.05). At 18 months, urine N-telopeptide levels (bone resorption marker), decreased from 439.7 to 222.3 BCE/Cr (p < 0.05), and serum ALP (bone formation marker) from 225.0 to 143.5 U/L (p < 0.05), reflecting reduced bone turnover. This may represent a net reduction in bone resorption, and provides a biochemical explanation for the increase in bone mineralisation. Height standard deviation scores were not affected, and there were no significant adverse effects.

Conclusion: 18 months cyclical pamidronate is effective in improving bone mineralisation, and reducing fracture incidence in O.I. Pamidronate therapy, which was safe, and when combined with intra-medullary rodding, can potentially improve the quality of life by improving mobility and preventing post-fracture deformities, thus offering new hope for children afflicted with OI.