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Bone & Joint Research
Vol. 11, Issue 11 | Pages 826 - 834
17 Nov 2022
Kawai T Nishitani K Okuzu Y Goto K Kuroda Y Kuriyama S Nakamura S Matsuda S

Aims

The preventive effects of bisphosphonates on articular cartilage in non-arthritic joints are unclear. This study aimed to investigate the effects of oral bisphosphonates on the rate of joint space narrowing in the non-arthritic hip.

Methods

We retrospectively reviewed standing whole-leg radiographs from patients who underwent knee arthroplasties from 2012 to 2020 at our institute. Patients with previous hip surgery, Kellgren–Lawrence grade ≥ II hip osteoarthritis, hip dysplasia, or rheumatoid arthritis were excluded. The rate of hip joint space narrowing was measured in 398 patients (796 hips), and the effects of the use of bisphosphonates were examined using the multivariate regression model and the propensity score matching (1:2) model.


The Bone & Joint Journal
Vol. 104-B, Issue 2 | Pages 200 - 205
1 Feb 2022
Orita K Goto K Kuroda Y Kawai T Okuzu Y Matsuda S

Aims

The aim of this study was to evaluate the performance of first-generation annealed highly cross-linked polyethylene (HXLPE) in cementless total hip arthroplasty (THA).

Methods

We retrospectively evaluated 29 patients (35 hips) who underwent THA between December 2000 and February 2002. The survival rate was estimated using the Kaplan-Meier method. Hip joint function was evaluated using the Japanese Orthopaedic Association (JOA) score. Two-dimensional polyethylene wear was estimated using Martell’s Hip Analysis Suite. We calculated the wear rates between years 1 and 5, 5 and 10, 10 and 15, and 15 and final follow-up.


The Bone & Joint Journal
Vol. 103-B, Issue 10 | Pages 1604 - 1610
1 Oct 2021
Takaoka Y Goto K Tamura J Okuzu Y Kawai T Kuroda Y Orita K Matsuda S

Aims

We aimed to evaluate the long-term outcome of highly cross-linked polyethylene (HXLPE) cemented acetabular components and assess whether any radiolucent lines (RLLs) which arose were progressive.

Methods

We retrospectively reviewed 170 patients who underwent 187 total hip arthroplasties at two hospitals with a minimum follow-up of ten years. All interventions were performed using the same combination of HXLPE cemented acetabular components with femoral stems made of titanium alloy. Kaplan-Meier survival analysis was performed for the primary endpoint of acetabular component revision surgery for any reason and secondary endpoint of the appearance of RLLs. RLLs that had appeared once were observed over time. We statistically assessed potential relationships between RLLs and a number of factors, including the technique of femoral head autografting and the Japanese Orthopaedic Association score.


Bone & Joint Research
Vol. 8, Issue 10 | Pages 451 - 458
1 Oct 2019
Kuroda Y Tanaka T Miyagawa T Kawai T Goto K Tanaka S Matsuda S Akiyama H

Objectives

Using a simple classification method, we aimed to estimate the collapse rate due to osteonecrosis of the femoral head (ONFH) in order to develop treatment guidelines for joint-preserving surgeries.

Methods

We retrospectively analyzed 505 hips from 310 patients (141 men, 169 women; mean age 45.5 years (sd 14.9; 15 to 86)) diagnosed with ONFH and classified them using the Japanese Investigation Committee (JIC) classification. The JIC system includes four visualized types based on the location and size of osteonecrotic lesions on weightbearing surfaces (types A, B, C1, and C2) and the stage of ONFH. The collapse rate due to ONFH was calculated using Kaplan–Meier survival analysis, with radiological collapse/arthroplasty as endpoints.


The Bone & Joint Journal
Vol. 101-B, Issue 7 | Pages 787 - 792
1 Jul 2019
Goto K Kuroda Y Kawai T Kawanabe K Matsuda S

Aims

In the 1990s, a bioactive bone cement (BABC) containing apatite-wollastonite glass-ceramic (AW-GC) powder and bisphenol-a-glycidyl methacrylate resin was developed at our hospital. In 1996, we used BABC to fix the acetabular component in primary total hip arthroplasty (THA) in 20 patients as part of a clinical trial. The purpose of this study was to investigate the long-term results of primary THA using BABC.

Patients and Methods

A total of 20 patients (three men and 17 women) with a mean age of 57.4 years (40 to 71), a mean body weight of 52.3 kg (39 to 64), and a mean body mass index (BMI) of 23.0 kg/m2 (19.8 to 28.6) were evaluated clinically and radiologically. Survival analyses were undertaken, and wear analyses were carried out using a computer-aided method.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_5 | Pages 6 - 6
1 Apr 2018
Goto K Katsuragawa Y Miyamoto Y Saito T Yamamoto T
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Aims

This study was conducted to investigate the influence of surgical experience on the outcomes and component positioning of total knee arthroplasty (TKA). We compared the outcomes and component positioning of simultaneous bilateral TKAs performed by supervisors and trainee surgeons.

Patients and Methods

A total of 20 patients (40 knees) who underwent simultaneous bilateral primary TKA using the same cruciate-retaining TKA system between 2011 and 2015 were included. The mean patient age was 76 years (range: 64 to 86 years). There were 2 males and 18 females. The first phase of the operation was performed on the knee that was more severely degenerated by one supervisor who had performed over 1000 TKAs. The other knee was operated on next by trainee surgeons who had performed less than 20 TKAs. The knees were categorized into two groups: those operated on by supervisors (group S) and those operated on by trainee surgeons (group T). Outcome measures included range of motion (ROM), Knee Score (KS), and Function Score (FS). We also evaluated operative time, alignment of the leg, and the orientation of components, which was determined on post-operative long-leg coronal films.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 56 - 56
1 Feb 2017
Kawata T Goto K So K Kuroda Y Okuzu Y Matsuda S
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Introduction

The long-term wear performance of highly cross-linked polyethylene (HXLPE) in cemented total hip arthroplasty (THA) has rarely been reported. Here we report a prospective randomized comparative analysis of radiographic wear after a minimum follow-up of 10 years in cemented THAs with either HXLPE or conventional polyethylene (CPE), and assess its clinical relevance.

Patients and Methods

From 1999 to 2001, we conducted 94 primary cemented THAs with a 22.225-mm head at our hospital as part of a prospective randomized trial. All surgeries were performed using a direct lateral approach with a trochanteric osteotomy (Dall's approach). The patients were divided into 4 groups. Twenty-six hips in group A were implanted with CPE sockets against zirconia heads and Charnley-type stems. HXLPE sockets (Aeonian, Kyocera Medical Corp) were implanted in all hips in the other 3 groups. Twenty-five hips in group B were implanted with zirconia heads and KC stems (Kyocera Medical Corp), 23 hips in group C with zirconia heads and distal cylindrical stems, and 20 hips in group D with stainless steel heads and C-stem (DePuy Inc). The sockets were highly cross-linked by gamma irradiation at a dose of 35 kGy, heat annealed at 110ºC, and sterilized with 25 kGy of gamma irradiation in nitrogen.

For radiographic evaluation, anteroposterior radiograms were taken for each patient annually, and every two years postoperatively for wear analyses. Two-dimensional head penetration was measured on each postoperative radiogram using a computer-aided technique.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 45 - 45
1 May 2016
So K Kuroda Y Goto K Matsuda S
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Introduction

Total hip arthroplasty (THA) for a highly dislocated hip can be problematic and technically challenging. Our previous study on cemented THA with subtrochanteric femoral shortening osteotomy revealed a high incidence (20%) of non-union. Therefore, in 2008, we introduced reverse hybrid THA using S-ROM stem for the treatment of a highly dislocated hip. The purpose of this study was to assess the short-term clinical outcomes of this new method.

Patients and methods

Between 2008 and 2014, 13 consecutive reverse hybrid THAs were performed on nine female patients with highly dislocated hips. The average age at the time of operation was 66 years (range, 55–85 years). The acetabular component was fixed in the true acetabulum with bone cement. Transverse osteotomy was performed below the lesser trochanter to shorten the femur and to prevent over-lengthening. The proximal sleeve of the S-ROM stem was then fixed within the proximal fragment, and the distal fin provided rotational stability of the distal fragment. Thus, the two fragments were fixed to each other with the S-ROM stem, and the resected segment was longitudinally cut for grafting at the junction. The postoperative follow-up period was an average of 4 years (range, 1–7 years), and no patients were lost. Preoperative and final Japanese Orthopaedic Association (JOA) hip score, operation time, bleeding amount, intraoperative and postoperative complications, bone healing at the osteotomy site, implant loosening, and revision surgery were retrospectively investigated.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_8 | Pages 5 - 5
1 May 2016
Goto K So K Kuroda Y Okuzu Y Matsuda S
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Background

Composite screws of uncalcined and unsintered hydroxyapatite (HA) particles and poly-l-lactide (PLLA) were developed as completely absorbable bone fixation devices. So far the durability of HA-PLLA composite screws is unclear when used for the fixation of acetabular bone graft in total hip arthroplasty under full-weight conditions. We have used this type of screw for the fixation of acetabular bone graft in cemented or reverse-hybrid total hip arthroplasty since 2003. Hence, we conducted a follow-up study to assess the safety and efficacy of these screws when used for cemented socket fixation.

Methods

During 2003–2009, HA-PLLA composite screws were used for fixation of acetabular bone graft in cemented or reverse-hybrid primary THA in 106 patients (114 cases). All the THAs were performed through direct lateral approaches, and postoperative gait exercise with full weight bearing usually started two days after surgery. One patient died of an unrelated disease and seven patients were lost to follow-up within 5 years. Finally, 98 patients (106 cases) were followed up for over 5 years and were reviewed retrospectively (follow-up rate, 93%). Radiographic loosening of the acetabular component was assessed according to the criteria of Hodgkinson et al., and the radiolucent line around the socket was evaluated in all zones, as described by DeLee and Charnley.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 7 - 7
1 Jan 2016
Goto K Kitamura N Koichi S Yokota M Wada S Yasuda K
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Introduction

Modular stems are commonly used to improve fixation in revision total knee arthroplasty (TKA). Hybrid fixation, in which cement is placed around the metaphysical portion of the component combined with an uncemented diaphyseal modular stem, has potential advantages including ease of insertion, improved component alignment, and ease of removal if needed. The aim of this study was to evaluate clinical results of revision total knee arthroplasty with uncemented modular stems using a hybrid fixation technique with a minimum 5-year follow-up.

Methods

23 revision TKAs were performed in 21 patients with hybrid fixation using uncemented modular stems. 3 patients (3 knees) had died of causes unrelated to the index arthroplasty at the time of the study, and 1 patient (1 knee) was lost to the follow-up. The remaining 19 knees were clinically and radiographically evaluated for the present study. The average follow-up time was 9.5 years. The average age of the patients was 70.5 years at the time of the revision surgery. The average time between the primary and revision surgeries was 10.6 years.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 8 - 8
1 Jan 2016
Goto K Fuyuya Y Masayuki S Matsuda S
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Postoperative peritrochanteric pain, which can be caused by non-union of the greater trochanter in those who have undergone total hip arthroplasty (THA) with trochanteric osteotomy, affects patient satisfaction. We reviewed 89 consecutive cases of primary THA performed with a mini-trochanteric direct lateral approach (Wafer approach), during which the anteroinferior trochanteric fragment (2 cm × 1 cm) attached to the anterior one-third or one-fourth of the gluteus medius muscle insertion and the entire insertion of the gluteus minimus muscle were osteotomized and detached using a curved chisel for exposure, while the origin of the vastus lateralis muscle remained intact. After completion of implantation, the detached fragment was fixed in the original position using 2 parallel braided sutures. If returning the trochanteric fragment to its original position was difficult, the tightened posterior tendinous portion of the gluteus minimus muscle was released to reduce the fragment easily and was then fixed. The surgeries, which included 19 cemented, 7 cementless, and 63 hybrid THAs, were performed between January 2012 and August 2013, and the patients [13 men, 76 women; average age, 65.6 years (38–86 years)] were followed for 6 months. The original diagnosis included primary osteoarthritis in 7 cases, osteoarthritis secondary to dysplasia in 75 cases, and avascular necrosis of the femoral head in 7 cases. X-ray examination including anteroposterior (AP) and lateral hip views was performed at 1, 3, and 6 months postoperatively, and a displacement of > 5 mm of the osteotomized fragment in either the AP or lateral view was considered fragment migration. The Japanese Orthopaedic Association (JOA) pain score was also recorded at 3 and 6 months postoperatively. We examined the possible factors affecting trochanteric migration and JOA pain score, including age, sex, THA type, leg lengthening, Crowe classification, and suture type. We also examined the correlation between trochanteric migration and JOA pain score. There were no peri- or post-operative complications including infection, deep venous thrombosis, dislocation, or periprosthetic fracture. No revision or radiographic loosening occurred in the follow-up period. Average leg lengthening was 9.8 mm (−4–21 mm), measured on the AP X-ray of the hip as the vertical interval between the pre- and postoperative positions of the lesser trochanter. There were 35 cases (39.3%) of trochanteric migration at postoperative 3 months. The Chi-square test and logistic regression analysis indicated that age, sex, Crowe classification, leg lengthening, and suture type did not affect trochanteric migration or JOA pain score. On the other hand, THA type did not affect trochanteric migration but did affect JOA pain score at postoperative 3 months. Patients who underwent cementless THA had worse JOA pain scores than the other patients. There was no correlation between trochanteric migration and JOA pain scores. The results indicated that trochanteric fragment migration often occurred in this series using the Wafer approach. Although the pain score is affected by many factors including thigh pain, hip abductor weakness, and wound irritation in the short term, it did not correlate with the trochanteric nonunion rate of this approach.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 110 - 110
1 Jan 2016
Kitamura N Goto K Kondo E Thoyama H Yasuda K
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Introduction

Ceramic total knee arthroplasty (TKA) was introduced as a new-generation of knee prostheses in clinical practice, and are expected to reduce polyethylene wear due to its resistance to abrasion and lubrication. In 1992, we developed a cruciate retaining LFA-I total knee prosthesis (KYOCERA Medical Co., Japan), which comprises an alumina ceramic femoral component and a titanium-alloy tibial component with a polyethylene insert. The purpose of this study was to evaluate clinical results in rheumatoid patients who were treated with the alumina-ceramic LFA-I prosthesis with a minimum 15-year follow-up period.

Methods

A total of 70 primary TKAs were performed in 51 patients between 1993 and 1996 using the cemented alumina-ceramic LFA-I prosthesis. Sixteen of these patients (20 knees) had died by the time of this study, of causes unrelated to the index arthroplasty, and 11 patients (16 knees) were lost to the follow-up. The remaining 34 knees were clinically and radiographically evaluated in the present study. The average follow-up time was 16.7 years. The average age of the patients was 58.2 years at the time of the operation. The clinical assessment was conducted with the Hospital for Special Surgery Knee rating score and the Knee Society scoring system. The component alignment and bone-implant interface were evaluated according to the Knee Society Roentgenographic Evaluation System.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 131 - 131
1 Jan 2016
Kuroda Y Manabu N So K Goto K Akiyama H Matsuda S
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Introduction

Ultra-high molecular weight polyethylene (UHMWPE) tape, which comprised threads of UHMWPE fibers with the thickness less than 0.5 mm, was developed as a flexible fixation device. We describe new techniques using UHMWPE tape for the reattachment of the osteotomised fragment and the repair of intraoperative calcar fractures in total hip arthroplasty (THA).

Patients & Methods

We reviewed the medical records and radiographs of the studied subjects after approval of this study by the institutional review board committee. Experiment 1: Between October 2011 and May 2012, 60 consecutive primary THAs were performed with the mini-trochanteric approach, which involved reattaching the osteotomised fragment using UHMWPE tape (Nesplon; Alfresa Pharma, Osaka, Japan). [Fig.1] By splitting the anterior one-fourth of the gluteus medius, the minitrochanteric osteotomy, a half-ellipsoid body about 15 mm long, 10 mm wide, and 5 mm deep, is performed using a curved chisel. After implanting of the prosthesis, the osteotomised fragment is reattached by using two 3-mm wide Nesplon tapes. Using 2.4 mm Kirshner wire, two sets of drill holes are created below the trochanteric bed of the femur. Nesplon tapes are passed through each drill hole and penetrated over the trochanteric fragment. Nesplon tape is tied using a double-loop sliding knot in conjunction with a special tightening gun tensioner up to 20 kgf. [Fig.2] The radiographic results were retrospectively analyzed to determine the incidence of nonunion and complications related to trochanteric site. Hip functional results were rated according to the Japanese Orthopedic Association (JOA) hip score. Experiment 2: Between July 2011 and May 2012, 5-mm wide Nesplon tapes were used for restoration of intraoperative femoral fractures in 4 primary THAs. For the repair of intraoperative proximal femoral fractures, 5-mm wide Nesplon tape is tightened with cerclage wiring technique using the gun tensioner up to 30 kgf. [Fig.3] The postoperative radiographic changes were analyzed.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 19 - 19
1 Jan 2016
So K Kuroda Y Goto K Matsuda S
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Introduction

In order to reduce polyethylene wear and incidence of osteolysis, and improve the long-term durability of total hip arthroplasty (THA), highly cross-linked polyethylene was introduced for clinical use in substitution for conventional polyethylene. We performed 35 cementless THAs between December 2000 and February 2002, and cross-linked polyethylene was used in these surgeries. The purpose of this study is to research linear wear rate of these hips, and to find the risk factor for high wear rate.

Patients and Methods

32 hips (26 patients) among the 35 could be evaluated at more than 10 years postoperatively. One hip required reoperations due to infection at 8 years postoperatively, and two were lost to followup in less than 10 years. There were 2 males and 24 females, and the observation period was 11.4 years in average (range 10?13 years). The age at the time of operation was 49.4 years in average (range 24?67 years), and body mass index was 22.4 in average (15?34). We used AHFIX total hip prostheses (KYOCERA Medical Corporation) for both acetabular and femoral replacement, and 22 mm Zirconia head was used in all cases. The median cup diameter was 46 mm (range 42?50). Osteolysis and loosening of the implant was evaluated on the anteroposterior radiograph of the hip. Using software for wear measurement (Hip Analysis Suite), linear wear rate and cup inclination angle were measured. Correlation between linear wear rate and age, BMI, cup inclination angle, and cup diameter was investigated using correlation coefficient.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_2 | Pages 5 - 5
1 Jan 2016
Goto K Kitamura N Kondo E Yokota M Wada S Thoyama H Yasuda K
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Introduction

Metals used for total knee arthroplasty (TKA) are well known for their good biocompatibility, but may be a source of a release of metal ions that can be a cause of local and systemic adverse effects, aseptic loosening, and hypersensitivity reactions. One of the major difficulties in performing TKA is the selection of implants for patients who are preoperatively diagnosed as subject to metal sensitivity. Alternative solutions in cases of hypersensitivity are implants without metal constituents or metallic implants treated with a non-sensitive surface process. The aim of this study was to evaluate clinical results in patients who had been preoperatively diagnosed with metal sensitivity and who subsequently were provided with the zirconia-ceramic LFA-III TKA, and with a minimum 5-year follow-up.

Methods

Five patients (8 knees) with metal sensitivity underwent TKA using cemented zirconia-ceramic LFA-III implants. The LFA-III implant (KYOCERA Medical Co., Japan) is composed of a zirconia ceramic femoral component and a titanium-alloy tibial component with a polyethylene insert. All patients were female andthe average age at the time of surgery was 76.1 years. The average follow-up time was 7.2 years. Clinical and radiographic assessments were conducted with the Knee Society scoring system.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 77 - 77
1 Jun 2012
Goto K Akiyama H Kawanabe K So K Nakamura T
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One cementless cup which had porous outer surface with Apatite-Wollastonite glass ceramic (AWGC) coating, was revised 13 years after primary THA because of massive osteolysis expanded to medial iliac wall along the screws. While many retrieved studies of hydroxyapatite-coated cup have been reported, there has been no report on the retrieved cup with AWGC coating. The purpose of this study was to describe this rare case in detail, confirm the bone ingrowth to the porous cup, and discuss on the effectiveness of porous surface with AWGC coating.

Case

The patient was a 64 old woman and complained of chronic mild pain around her left groin region. X-ray examination revealed that osteolysis had been expanding around the screws and extended proximally. The revision surgery was performed for the massive osteolysis through Hardinge antero-lateral approach. The retrieved implants included a cementless cup made of titanium alloy (QPOC cup, Japan Medical Materirals Inc.(JMM) Osaka, Japan), the outer surface of which was plasma-sprayed with titanium for porous formation and coated with AWGC in the deep layer. It was found that the polyethylene liner was destructed partially in the supero-lateral portion, but the cup was well fixed to the bone. The bone-attached area was found to be dispersed over the porous surface of the hemispherical cup. Histological examination revealed that matured bony tissue intruded into the porous surface of the cup, and contacted to bone directly, which was also demonstrated in the back-scattered electron image. It was also demonstrated that there were residual silicon (Si) rich regions on the porous surface by the SEM-EDX analysis, which indicated that constituents of AWGC still remained on the surface. On the other hand, the results of elementary analyses in the Si rich regions varied among the sections, which probably indicated that the extent of degradation and absorption of AWGC varied among the sections.

AWGC was one of the bioactive ceramics and reported to have an ability to bond to bone earlier than hydroxyapatite (HA). In the present case, though massive osteolysis occurred with aggressive wear, it did not expand on the porous surface, and rather progressed along the smooth surface of the screws. Considering that there are many clinical studies reporting poor clinical results of HA-coated smooth cups, bioactive ceramic coating may function well and bring superior clinical results when combined with porous coated substrate. In our study, though the cause of massive polyethylene wear and intrapelvic giant osteolysis could not be revealed, the porous cup with AW-GC bottom coating was well fixed and gained bone-ingrowth at the porous surface under osteolytic conditions, which may demonstrate the long-term durability of this surface treatment.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 416 - 416
1 Nov 2011
Nakamura T Fukuda C Imamura M Goto K Kokubo T
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Many types of bioactive bone cement have been developed to overcome the disadvantages of polymethyl-methacrylate (PMMA) bone cement, especially its lack of bone-bonding ability, which occasionally leads to aseptic loosening of prostheses used for arthroplasty. Earlier, we showed that bioactive bone cements containing either nano-sized or micron-sized titania (TiO2) particles had excellent in vivo osteoconductivity.

However, anatase phase titania particles contained in these bioactive bone cements raise concerns about their safety in vivo. We developed pure rutile micron-sized titania particles. because rutile is the only stable phase, whereas anatase is metastable.

In this study, polymethylmethacrylate (PMMA)-based bone cement containing pure rutile micron-sized titania (TiO2) particles were developed, and their mechanical properties and osteoconductivity are evaluated. The three types of bioactive bone cement were T10, T20, and T30, which contained 10, 20, and 30wt% TiO2, respectively.

Commercially available PMMA cement (PMMAc) was used as a control. Hardened cylindrical cement sample (φ2.5mm*10mm) was inserted manually on rabbit femur vertically. Push out test was performed for evaluation of bonding strength. For mechanical testing, the flexural strength, flexural modulus, and compressive strength were measured.

Results of this study revealed that polymethylmeth-acrylate (PMMA)-based bone cement containing pure rutile micron-sized titania particles has outstanding osteoconductivity in vivo, and their mechanical properties were exceeded that of commercially available PMMA cement. Interfacial shear strength of T10, T20 and T30 were 17.1~24.0MPa each at 12 weeks, and were significantly higher than PMMAc. In general, the interfacial bonding strength of bone cement depends mainly on its interdigitation with cancellous tissue, which is accomplished by the pressurized injection of the cement in paste form. On the other hand, we inserted the hardened specimens into oversized holes on rabbit femur in this study, because we intended to examine the osteoconductive and bone-bonding potentials of each material. The flexural strength, flexural modulus, and compressive strength were equivalent to or exceeded that of PMMAc.

These results show that bone cement containing pure rutile micron-sized titania particles is a promising material applied to prosthesis fixation as well as vertebroplasty.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 413 - 413
1 Nov 2011
Goto K Akiyama H Kawanabe K Sou K Nakamura T
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Poly-L-lactic acid (PLLA) is characterized by its biocompatibility and biodegradability, and is used clinically. In our hospital, we started to use PLLA screws instead of metallic or ceramic screws in the fixation of acetabular bone grafts in total hip arthroplasty (THA) in 1990, because there were concerns about the use of rigid and nonbioabsorble screws, which might contribute to the absorption of the grafted bone and induce metallosis or third-body wear when breakage of the screws occurs. The purpose of this study was to review a series of cemented THA for dysplasia, with structural autograft fixed with PLLA screws. We focused on the survival rate of the acetabular component and radiological change of the grafted bone–socket interface.

This study included 104 consecutive cemented total hip arthroplasties (80 patients) performed between July 1990 and December 1995 in our hospital. All patients were followed over 10 years and reviewed retrospectively. The grafted bone trimmed from the excised femoral head was fixed rigidly with 1 or 2 PLLA screws (cancellous lag screws 6.5 mm in bore diameter and 4.1 mm in grove diameter) (Fixsorb; Takiron Co., Ltd., Osaka, Japan).

X-ray photographs taken just after the primary operation showed an obscure but still visible radiolu-cent region corresponding to the inserted PLLA screws in many cases.

However, X-ray photographs at the final follow-up showed an unclear radiolucent zone at the sites of the PLLA screws, and the osteosclerotic line surrounding the site where the radiolucent zone had been found was confirmed in only 4 cases. Bone union was confirmed radiologically at the grafted site in every case, and there were no cases of early collapse or extravasation of the grafted bone. No positive resorption of the grafted bone was observed in any case. Kaplan–Meier survivorship analysis of socket revision, radiological loosening of the socket, and the appearance of a radiolucent line > 1 mm in the graft–socket interface as the endpoints indicated survival rates of 99%, 97.1%, and 63.5% at 10 years, and 96.6%, 90.2%, and 56.1% at 15 years, respectively.

The results of this study indicated that PLLA screws are safe and useful for the fixation of acetabular bone graft concomitant to cemented THA with a careful rehabilitation program. However, because of concern about the mechanical insufficiency of the PLLA screws for THA with an early weight-bearing rehabilitation program, we have used mechanically stronger and bioabsorbable screws made of forged composites of hydroxyapatite and PLLA since 2003.


The Journal of Bone & Joint Surgery British Volume
Vol. 93-B, Issue 9 | Pages 1194 - 1200
1 Sep 2011
Akiyama H Yamamoto K Tsukanaka M Kawanabe K Otsuka H So K Goto K Nakamura T

We retrospectively reviewed 40 hips in 36 patients who had undergone acetabular reconstruction using a titanium Kerboull-type acetabular reinforcement device with bone allografts between May 2001 and April 2006. Impacted bone allografts were used for the management of American Academy of Orthopaedic Surgeons Type II defects in 17 hips, and bulk bone allografts together with impacted allografts were used for the management of Type III defects in 23 hips. A total of five hips showed radiological failure at a mean follow-up of 6.7 years (4.5 to 9.3), two of which were infected. The mean pre-operative Merle d’Aubigné score was 10 (5 to 15) vs 13.6 (9 to 18) at the latest follow-up. The Kaplan-Meier survival rate at ten years, calculated using radiological failure or revision of the acetabular component for any reason as the endpoint, was 87% (95% confidence interval 76.3 to 97.7). A separate experimental analysis of the mechanical properties of the device and the load-displacement properties of bone grafts showed that a structurally hard allograft resected from femoral heads of patients with osteoarthritis should be preferentially used in any type of defect. If impacted bone allografts were used, a bone graft thickness of < 25 mm was acceptable in Type II defects.

This clinical study indicates that revision total hip replacement using the Kerboull-type acetabular reinforcement device with bone allografts yielded satisfactory mid-term results.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 111 - 111
1 Mar 2010
Akiyama H Kawanabe K Goto K So K Nakamura T
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Removal of femoral bone cement is required for preparation of proper implant bed for reimplantation of a new femoral component in revision total hip arthroplasty. Several devices and procedures have been developed for cement removal, including an extracorporal shock-wave lithotripter and YAG laser, as well as a high-powered drill or burr under the control of conventional fluoroscopic images and an intrafemoral endoscopy. Ultrasonic tools are efficient for removal of bone cement with minimal damage to bone. We use a high-powered burr to remove the deep femoral bone cement under the control of conventional fluoroscopic images, although the problem of this procedure is large exposure of X-ray and two dimensional viewing of burr position which can result in perforation in the third plane.

Computer-assisted fluoroscopic navigation system allows the surgeons to provide positional information about surgical instrument to target bones during operations. Two-dimensional image data are obtained using the fluoroscope with a reference frame and stored on a computer workstation. A camera interfaced with the computer then tracks the position of the patient and registered surgical instruments during the procedure. Taking advantage of the real-time guidance of computer-assisted fluoroscopic navigation system, we introduce a valuable technique using computer-assisted fluoroscopic navigation system for performing removal of the cement of the femoral canal in revision cemented total hip arthroplasty.