header advert
Results 1 - 20 of 20
Results per page:
Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_10 | Pages 6 - 6
1 Oct 2020
Maruyama M Moeinzadeh S Guzman RA Takagi M Yang YP Goodman SB
Full Access

Introduction

In early stage osteonecrosis of the femoral head (ONFH), core decompression (CD) is often performed; however, approximately 30% of CD cases progress to femoral head collapse. Bone healing can be augmented by preconditioning MSCs (pMSCs) with inflammatory cytokines. Another immunomodulatory approach is the timely resolution of inflammation using cytokines such as IL-4. We investigated the efficacy of pMSC and genetically modified MSCs that over-express IL-4 (IL4-MSCs) on steroid-associated ONFH in rabbits.

Methods

Thirty-six male skeletally mature NZW rabbits received methylprednisolone acetate (20mg/kg) IM once 4 weeks before surgery. There were 6 groups:

CD alone – a 3 mm drill hole

+ injection into the CD of:

hydrogel (HG) - 200 μl of hydrogel carrier

MSCs–1 million rabbit MSCs

pMSC - LPS (20 μg/ml) + TNFα (20 ng/ml) preconditioned MSCs

IL4-MSCs – rabbit IL-4 over-expressing MSCs

IL4-pMSCs – preconditioned IL-4 over-expressing MSCs

Eight weeks after surgery, femurs were harvested, and evaluated by microCT, biomechanical, and histological analyses.


Bone & Joint Research
Vol. 8, Issue 10 | Pages 481 - 488
1 Oct 2019
Nathan K Lu LY Lin T Pajarinen J Jämsen E Huang J Romero-Lopez M Maruyama M Kohno Y Yao Z Goodman SB

Objectives

Up to 10% of fractures result in undesirable outcomes, for which female sex is a risk factor. Cellular sex differences have been implicated in these different healing processes. Better understanding of the mechanisms underlying bone healing and sex differences in this process is key to improved clinical outcomes. This study utilized a macrophage–mesenchymal stem cell (MSC) coculture system to determine: 1) the precise timing of proinflammatory (M1) to anti-inflammatory (M2) macrophage transition for optimal bone formation; and 2) how such immunomodulation was affected by male versus female cocultures.

Methods

A primary murine macrophage-MSC coculture system was used to demonstrate the optimal transition time from M1 to M2 (polarized from M1 with interleukin (IL)-4) macrophages to maximize matrix mineralization in male and female MSCs. Outcome variables included Alizarin Red staining, alkaline phosphatase (ALP) activity, and osteocalcin protein secretion.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_6 | Pages 115 - 115
1 Mar 2017
Maruyama M Yoshida K Tensho K Wakabayashi S Shimodaira H Tanaka M
Full Access

Background

Although the wear of conventional polyethylene liner becomes a serious problem in a long term follow up after total knee arthroplasty, there are few reports of measuring the polyethylene wear.

Questions/purposes

Is it possible to measure the linear wear rates in the non-cross-linked polyethylene liner used in the Press Fit Condylar (PFC) Sigma total knee system? Does the polyethylene wear influence on the clinical results?


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 140 - 140
1 Feb 2017
Maruyama M Wakabayashi S Ota H Tensho K Nakasone J
Full Access

Introduction

Acetabular bone deficiency, especially proximal and lateral deficiency, is a difficult technical problem during primary total hip arthroplasty (THA) in developmental hip dysplasia (DDH). We report a configuration-based classification of hip, including a definition of shallow acetabulum. We also report a new reconstruction method using a medial reduced cemented socket and additional bulk bone in conjunction with impaction morselized bone grafting (Ad-BBG method). We aimed to evaluate usefulness of the classification and the method's clinical/radiographic outcomes.

Methods

Forty percent of 330 THAs for DDH were defined as shallow dysplastic hips. The Ad-BBG method was performed on 102 hips (78% of shallow hips). For the 24 remaining hips, THA was performed using the conventional interposition bulk bone grafting (8 hips)or without bone grafting by using rigid lateral osteophyte (16 hips). Operative Technique: Theresected femoral head was sectioned at 1–2-cm thickness, and a suitable size of the bulk bone graft was placed on the lateral iliac cortex and fixed by polylactate absorbable screws. Autogenous impaction morselized bone grafting, with or without hydroxyapatite granules, was performed along with the implantation of medial reduced cemented socket. Radiographic criteria used for determining loosening were migration or a total radiolucent zone between the prosthesis/bone cement and host bone. The follow-up period was 10.2 ± 2.6 (range, 6.0–15.0) years.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 31 - 31
1 May 2016
Maruyama M Shimodaira H
Full Access

OBJECTIVE OF THE STUDY

The objective of this study is to establish the medium-term clinical and radiological results with the cementless three-dimensional Vektor-Titan stem compared with conventional cementless stem, such as PerFix stem. The latter stem has a double-wedge design with a rounded distal portion for canal filling (Fig. 1).

MATERIALS AND METHODS

From July, 2004, to May, 2010, fifty seven Vektor-Titan stems and 150 PerFix stems were implanted for the patients with osteoarthritis, avascular necrosis, femoral neck fracture, and rheumatoid arthritis in our hospital. The results were evaluated clinically using Japanese Orthopedic Association (JOA) scores and the Merle d’Aubigne and Postel (M&P) scores. Radiographs were analyzed retrospectively. The criteria used for determining loosening were migration or a total radiolucent zone between the prosthesis/bone cement and host bone, wherein the width increased progressively or change of position, i.e., migration or subsidence of the prosthesis. Migration of the socket seen on the radiograph was defined as either the presence of a ≥2-mm position change or rotation. Position changes of the stem seen on the radiograph were defined as the presence of a progressive subsidence of ≥2 mm or change of position, e.g., varus or valgus. The follow-up period was 9.2 ± 2.6 (range, 5.0–14.0) years.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_9 | Pages 22 - 22
1 May 2016
Maruyama M Wakabayashi S Ota H Nakasone J
Full Access

Introduction

Acetabular bone deficiency, especially proximal and lateral deficiency, is a difficult technical problem during primary total hip arthroplasty (THA) in developmental hip dysplasia (DDH). We report a configuration-based acetabular classification, a modification of the Crowe's classification, of DDH, including a definition of shallow acetabuli. We also report a new reconstruction method using a medial reduced cemented socket andadditional bulk bone in conjunction with impaction morselized bone grafting (Ad-BBG method). We aimed to evaluate usefulness of the classification and the method's clinical/radiographic outcomes.

Methods

One hundred thirty one hips of 330 THAs for DDH (40%) were defined shallow. The Ad-BBG methodwas performed on 102 hips (78% shallow hips). For the 24 remaining hips, THA was performed using the conventional interposition bulk bone grafting (Ip-BBG) (8 hips)or without bone grafting by using rigid lateral osteophyte (16 hips). Japanese Orthopaedic Association (JOA) scores and the Merle d'Aubigne and Postel (M&P) scores were used in follow-up; radiographs were analyzed retrospectively. The criteria used for determining loosening were migration or a total radiolucent zone between the prosthesis/bone cement and host bone. The follow-up period was 9.2 ± 2.6 (range, 5.0–14.0) years.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_8 | Pages 122 - 122
1 May 2016
Maruyama M Koyama S
Full Access

BACKGROUND

During revision hip arthroplasty, removal of a well-fixed, ingrown metal acetabular component may not be possible. Therefore, a new polyethylene liner can be cemented into the existing shell via the cement locking mechanism. We report the indications, technique, and results of cementing an acetabular liner into a well-fixed cementless acetabular shell.

PATIENTS AND METHODS

All patients were given informed consent to participate in this study, and the study was approved by our hospital institutional review board. Of 95 revision total hip arthroplasty (THA) between 2005 and 2014, five hips in 5 patients (4 female and a male) were operated by the cemented socket into metal shell technique. The mean age was 70.6 years (range, 59–84 years) (Table 1).


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 21 - 21
1 Jan 2016
Maruyama M Tensho K Wakabayashi S Hisa K
Full Access

BACKGROUND

There is no report of additional type of bulk bone grafting (Ad-BG) method with impaction morselized bone graft for reconstruction of shallow dysplastic hip in total hip arthroplasty. The purpose of this study was to define the shallow acetabulum and to evaluate the clinical and radiographic results of primary total hip arthroplasty (THA) with Ad-BG method.

MATERIALS and METHODS

With modification of Crowe's classification, shallow dysplasia was defined and classified (Fig. 1). Between October 1999 and August 2008, 120 hips of 302 THAs for dysplastic hip were defined as shallow and Ad-BG was done in 96 hips (80% of shallow hips). For 24 hips with shallow dysplasia, THA were performed by using conventional type of interpositional bulk bone graft (Ip-BG) (8 hips) or without bone graft by using rigid lateral osteophyte. All patients were followed clinically using the Japanese Orthopaedic Association (JOA) score and also Merle d'Aubigne and Postel (M&P) scores in a prospective fashion, and radiographs were analyzed retrospectively. The criteria used for determining loosening were migration or total radiolucent zone between the prosthesis (or bone cement) and host bone. The mean follow-up periods were 8.0 ± 2.3 (5.0–13.5) years.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 411 - 411
1 Dec 2013
Maruyama M Tensho K Wakabayashi S Hisa K
Full Access

BACKGROUND:

Although most radiographs used for polyethylene wear measurements have been taken with the patient in the supine position in order to assess penetration by the femoral head into the acetabular polyethylene socket, we have questioned the effect of weight-bearing on the position of the head within the socket. The current study aimed to determine the effect of weight bearing, i.e. standing on the two-dimensional radiographic position of the femoral head within the socket.

PATIENTS AND METHODS:

A total of three hundred and fifty patients (three hundred and eighty three hips) who had had a total hip arthroplasty had digital radiographs made a set of anteroposterior radiographs for each patient: one radiograph was made with the patient supine and one was made with the patient standing in full weight bearing on the replaced hip. The patients were divided into the following two groups: 1) seventy-five patients (eighty-three hips) with conventional polyethylene (CON) (group-1); 2) two hundred and seventy-five patients (three hundred hips) with highly cross-linked polyethylene (XPL) (group-2).

The set of radiograph was taken at three weeks postoperatively and at the time of semiannual follow-up. The average ceramic femoral head penetration was measured with radiographs taken in the standing or supine position at the final follow-up and compared with those of three weeks postoperatively. A single researcher with use of a computerized measurement system performed all measurements on the radiographs of the two-dimensional position of the head. Follow-up period were 13.5 ± 1.0 (range. 11.0–15.5) years in group-1 and 7.6 ± 2.1 (range. 5.0–12.6) years in group-2.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 534 - 534
1 Dec 2013
Shimodaira H Tensho K Maruyama M
Full Access

BACKGROUD/PURPOSE

Recently, the use of a large diameter femoral head has been discussed as a means to reduce the risk of hip dislocation after total hip arthroplasty (THA). Although it has been clear that increasing the head size increases the oscillation angle and hip stability, a consensus on the usefulness of a larger head size has not been reached due to an increased propensity for bone impingement. We studied the effect of the range of motion (ROM) and bone impingement caused by increasing the femoral head size using a 3D simulation system.

PATIENTS AND METHODS

All patients who had undergone a primary THA in our hospital from October 2010 were selected, and we excluded those with severe osteoarthritis, severe dysplasia (Crowe group), or excessive femoral neck anteversion (35°). This resulted in 60 patients (16 men and 44 women), with a mean age of 66.6 years (range, 47–83 years). The diagnoses were osteoarthritis in 42 hips, osteonecrosis in 11 hips, rheumatoid arthritis in four hips, and femoral neck fracture in three hips. A virtual hip model was generated from the preoperative CT scan and a component was virtually implanted via computer simulation software (Zed Hip, LEXI, Japan). The acetabular cup was implanted with an inclination of 45°, anteversion of 20°, and the femoral stem was implanted into the femur recreating the same head height with an anteversion of 25°. We defined three leg positions: (A) maximum flexion (B) internal rotation with hip in 90°of flexion and 20°of adduction as posterior dislocation, and (C) external rotation with hip in 0°of extension as anterior dislocation. In each leg position, range of motion up to the impingement and the type of impingement (implant or bone) was assessed with 22-, 26-, 28-, 32-, and 36 mm femoral head sizes.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 599 - 599
1 Dec 2013
Maruyama M Yoshida K Kitagawa K
Full Access

We reported a case of the acetabular depression fracture in conjunction with a central fracture dislocation of the hip that was treated with a unique surgical technique.

CASE REPORT:

A 76-year-old man suffered a left acetabular fracture with severe left hip joint pain and walking disability. Acetabular fracture was not apparent on the initial radiographs including anteroposterior and oblique views of the pelvis. However, computed tomography (CT) scanning showed displaced acetabular depression fracture (a third fracture fragment) in the center of the weight-bearing area with fracture of the ilium and spontaneous reposition of central dislocation of the hip (Fig. 1, 2). It seemed that this fracture fragment created incongruity of the acetabular articular surface and the potential for hip joint instability. Therefore, the patient was treated with open reduction and internal fixation.

SURGICAL TECHNIQUE:

To perform the procedure, the patient was placed in the lateral decubitus position. A direct lateral approach to the hip was used for exposure. The vastus lateralis was released 1 cm distal from its origin, trochanteric osteotomy was done by the Gigli saw. To observe the hip articular surface and to identify the fracture fragment, the femoral head was posterior dislocated with excision of teres ligamentum after T-shaped capsulotomy. The depressed fragment in the acetabulum was identified under direct vision but could not be reduced. Therefore, the outer cortex of the ilium was fenestrated in a size of 2 × 2 cm so that a 1-cm-wide levator was inserted to the depressed fragment at 2 cm proximal from the hip articular surface through the fenestrated window (Fig. 3). Subsequently, the displaced bone fragment was pushed down by using the levator to the adequate articular joint level. The fragment was stabilized with packed cancellous bone graft harvested from the osteotomized greater trochanter. The removed outer cortex of the ilium from fenestrated site was repositioned and fixed by a reconstruction plate and screws. The osteotomized greater trochanter was reattached and fixed with two cannulated cancellous hip screws.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 76 - 76
1 Mar 2013
Ichinohe S Tajima G Kamei Y Maruyama M Shimamura T
Full Access

It is very difficult to perform total knee arthroplasty (TKA) for severe varus bowing deformity of femur. We performed simultaneous combined femoral supra-condyle valgus osteotomy and TKA for the case had bilateral varus knees with bowing deformity of femurs.

Case presentation

A 62-year-old woman consulted our clinic with bilateral knee pain and walking distability. She was diagnosed rickets and had bilateral severe varus bowing deformity of femurs from an infant. Her height was 133 cm and body weight was 51 kg. Bilateral femur demonstrated severe bowing and her knee joint demonstrated varus deformity with medial joint line tenderness, no local heat, and no joint effusion. Bilateral knee ROM was 90 degrees with motion crepitus. Bilateral lower leg demonstrated mild internal rotation deformity. Bilateral JOA knee score was 40 Roentgenogram demonstrated knee osteoarthritis with incomplete development of femoral condyle. Mechanical FTA angles were 206 degree on the right and 201 on the left. She was received right simultaneous femoral supra-condyle valgus osteotomy with TKA was performed at age 63. Key points of surgical techniques were to use the intramedullary guide for valgus osteotomy as temporary reduction and fixation then performed mono-cortical locking plate fixation. Several mono cortical screws were exchanged to bi-cortical screws after implantation of the femoral component with long stem. Cast fixation performed during two weeks and full weight bearing permitted at 7 weeks after surgery. Her JOA score was slightly improved 50 due to other knee problems at 9 months after surgery, her right mechanical FTA was decreased to 173, and she received left simultaneous femoral supra-condyle valgus osteotomy with TKA as the same technique at April of this year. She has been receiving rehabilitation at now.

Conclusions

Most causes of varus knee deformity are defect or deformity of medial tibial condyle and TKA for theses cases are not difficult to use tibial augment devices. However the cases like our presentation need supra-femoral condyle osteotomy before TKA. It was easy and useful to use intramedullary guide for valgus osteotomy as temporary reduction and fixation then performed mono-cortical locking plate fixation before TKA.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 254 - 254
1 Mar 2013
Maruyama M Wakabayashi S Tensho K
Full Access

BACKGROUND

Hybrid total hip arthroplasty (THA) commonly recognized as cementless hemi-spherical acetabular component combined with cemented femoral stem. We have done so called “reverse” hybrid THA with cemented socket and cementless stem and compared with all-cemented THAs.

PATIENTS AND METHODS

We have been collecting data on total hip arthroplasty since November, 1993. Reverse hybrid hip replacements were used mainly from February, 2001. We evaluated data on 272 reverse hybrid THAs (223 patients) from this year onward until May, 2010, and compared the results with those from 283 all-cemented THAs (237 patients) between 1993 and May, 2010. Eighty percent or more of patients had diagnosed as secondary osteoarthritis of the hip joint due to dysplasia in our hospitals. Highly cross linked ultrahigh molecular polyethylene (CLP) socket was introduced in October, 1999. We used conventional (not cross linked polyethylene) socket for 82 hips (cemented group-1) operated before October, 1999 and CLP socket for 201 hips (cemented group-2) in all-cemented cases. We used the Kaplan-Meier method for estimation of prosthesis survival and relative risk of revision. The endpoint was radiological loosening or revision. Socket linear wear rates were also assessed in radiographically. Clinical assessment was performed using the Japanese Orthopedic Association (JOA) scores and Merle d'Aubigne & Postel scores.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 253 - 253
1 Mar 2013
Maruyama M
Full Access

OBJECTIVE OF THE STUDY

The objective of this study is to establish the short-term and medium-term clinical and radiological results with the cementless three-dimensional Vektor-Titan stem (Figure 1). This three-dimensional tapered stem has been given to evaluate the extent to which the implant design achieves an optimal proximal anchoring property, thus reducing bone atrophy and avoiding stress shielding in the proximal femur.

MATERIAL AND METHODS

From July, 2004, to May, 2010, 80 Vektor-Titan stems were implanted in 75 patients in the Shinonoi General Hospital. Forty two patients (42 hips) with femoral neck fracture (FNF) and one patients (2 hips) with aseptic necrosis of the femoral head (ANF) were died or impossible to come outpatient clinic for postoperative follow-up due to serious illness not related to the surgery. Of 32 patients (36 hips) with a minimum two-year follow-up, 23 patients (23 hips) with FNF and 9 patients (13 hips) with ANF were analyzed in the study. Demographics and clinical outcomes of the patients were shown in Table 1. The results were evaluated clinically using Japanese Orthopedic Association (JOA) Scores and radiologically within the scope of a retrospective cohort study.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XL | Pages 107 - 107
1 Sep 2012
Maruyama M
Full Access

BACKGROUND

Our modified procedure for rotational acetabular osteotomy (RAO) aimed to reduce operative invasion of soft tissue and to minimize incision length.

SURGICAL TECHNIQUE

A shortened skin incision (10–15 cm versus 20–30 cm in traditional RAO) is curved over greater trochanter and exposed by transtrochanteric approach. Medial gluteus muscle is retracted to expose the ilium without detachment from iliac crest. Similarly the rectus femoris muscle tendon was retracted, not excised, from the anterior inferior iliac spine. The lateral part of the osteotomized ilium is cut in lunate and trapezoid shape to form the bone graft instead of the outer cortical bone of the ilium.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 139 - 139
1 Jun 2012
Maruyama M Tensho K Wakabayashi S Kitagawa K
Full Access

BACKGROUND

Acetabular defects are encountered in both primary total hip arthroplasty (THA) in patients with developmental dysplasia of the hip (DDH) and in revision THA. The purpose of this study was to evaluate the clinical and radiographic results of one method of acetabular reconstruction for THA using a hydroxyapatite (HA) block with either an autogenous graft or allograft of impacted morsellized bone in conjunction with a cemented socket.

METHODS

Fourteen hips in 14 patients (all female; average age, 64 years) were treated with the above technique in primary (11 DDH) or revision THA (three loosened sockets). All patients were followed clinically in a prospective fashion, and radiographs were analyzed retrospectively. One initial patient had 16-year follow-up, whereas the remaining 13 patients had follow-up between four and 5.5 years.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 140 - 140
1 Jun 2012
Maruyama M
Full Access

Internal fixation for supracondylar fracture of the femur after total knee arthroplasty (TKA) is technically difficult and troublesome because the distal bony fragment is often osteoporotic and too small to fix by screws or K-wires. In addition, the femoral component interferes with the screws or K-wires to be inserted from distal direction for fixation of the fracture.

Patients and Methods

Four knees in 4 patients (all female; average age, 81.5 +/− 2.6 years) with the fracture after TKA were treated with revision TKA. Follow-up period was between six months and 3 years postoperatively

Operative technique

All operations were performed with the patient in the supine position and using a curved anterior (Payer) approach with or without osteotomy of the tuberositas tibiae. The femoral component was removed with detachment from fractured bony fragments. New femoral component with long stem for fixation of the fracture were inserted with bone cement in each case.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 144 - 144
1 Mar 2010
Tensho K Kodaira H Yasuda G Saito N Maruyama M Terayama K
Full Access

Long term outcome of cementless femoral stem with use of transtrochanteric approach was evaluated by clinical outcome and radiological change.

37 joints in 33 patients who underwent surgery in our department more than 15 years before (from 1986 to 1993) were studied. Used implants were Omnifit (Fit group, 19 joints: all joints were microstructured) and Ominiflex (Flex group, 18 joints: all joints were microstructured). The preoperative diagnosis was secondary osteoarthritis caused by dysplasia of hip (29 joints), osteonecrosis of femoral head (2 joints), rheumatoid arthritis (4 joints), and others (2 joints). Mean age at surgery was 51 years (Fit group, 54.2 years; Flex group, 50.2 years) and average postoperative follow-up period was 17.8 years (Fit group, 19 years; Flex group, 16.5 years). Clinical outcome was evaluated by Japanese Orthopedic Association hip score (JOA score) and absence or presence of thigh pain. In radiological evaluation, the fixation of implant was evaluated by Engh’s classification and the presence or absence of stress shielding, spot welds, radiolucent line, osteolysis, and sinking were studied.

JOA score for Fit and Flex group was significantly improved from 35 to 79.3 points and 37 to 76.9 points, respectively. Improvement of pain and gait ability was marked. Thigh pain was observed in 1 joint only, in the Flex group. Radiological examination for Fit and Flex group showed bone ingrowth 100% and 61% of patients, respectively, showing good fixation for both groups. Radiological sign of Fit and Flex group showed stress shielding in 91% and 84%, spot welds in 73% and 44%, radiolucent line in 12% and 19%, osteolysis in 5.2% and 5%, and sinking in 0% and 11% of patients, respectively. Revision caused by loosening of stem was in only 1 joint in Flex group.

For first generation of Omnifit/Omniflex stem, many cases of early loosening caused by surface structure characteristics had been reported. Long-term outcome in our department was relatively good compared to these earlier reports. Good initial placement of femoral component and sufficient canal fill ratio with use of transtrochanteric approach is one factor of this better result.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 113 - 113
1 Mar 2010
Maruyama M Kitagawa K Ono S Tensho K
Full Access

A seventy-one-years old, female, has been treated by hemodialysis from 1977 due to renal failure. In April 19, 1985, she had Charnley Low Friction Arthroplasty for right hip joint. She often felt mild pain on the joint from 2000. Radiograph showed central migration of the socket and huge cystic bone defect of the acetabulum surrounded by thin cortical bone like an egg-shell form. Tear drop (acetabular floor) was diminished due to massive bone destruction or severe osteolysis. CT showed that the diameter of the cavity was approximately 10 cm. In March 1, 2002, the socket was upside down and moving freely in the cavity. The patient could not weight-bear on right lower extremity but walk without two crutches. Hemiarthroplasty for her left hip joint (contra-lateral side) was done in June 26, 2006, due to femoral neck fracture. Because of continuous right hip joint pain and walking disturbance, she underwent revision surgery in May 20, 2008. At the surgery, the cavity was empty except for the socket and fibrous tissue. Impaction grafting by using morselized allograft including porous and solid hydroxyapatite granules (100 g and 40 g each) was done after the socket and the tissue were extracted. A custom made all polyethylene socket (73 × 68 mm in diameter) was fixed by polymethylmetacrylate bone cement. Postoperative course was uneventful. She can walk with one crutch and ride on/off a vehicles without help four months postoperatively.

It is often difficult to reconstruct acetabulum with large bone defect in revision total hip arthroplasty. Especially, almost of support rings with hook cannot be applied in the case that the tear drop is destructive or absorbed. Impaction bone grafting is commonly used for reconstruction of bone defect in revision surgery. However, the extremely thick graft for large bone defect is at risk of collapsing lead to implant migration. The socket used in the case was custom made jumbo type to reduce the thickness of impaction grafting. It seems to be one of resolution to use the custom made jumbo socket for the case with large defect of acetabulum in revision total hip Arthroplasty.


The Journal of Bone & Joint Surgery British Volume
Vol. 77-B, Issue 2 | Pages 213 - 218
1 Mar 1995
Maruyama M

A clay containing hydroxyapatite (HA) was developed for use as a filling material between an uncemented implant and bone. It consists of 55% HA granules greater than 0.1 mm in size with a homogeneous pore distribution and a porosity of 35% to 48% in a saline solution of sodium alginate (6%). Ti-6A1-4V alloy rods with smooth surfaces were implanted into the distal medullary canal of one osteotomised tibia of 32 Japanese white rabbits. Sixteen rods were inserted with HA clay and 16 without the clay to act as a control group. Six of each group were killed at one week and ten at 12 weeks postoperatively. The pull-out strength of the implants with HA clay was significantly greater at 12 weeks (p < 0.05), as was the percentage of the area of the new bone (p < 0.05). The study suggests that HA clay has an osteoconductive property, allowing adequate bone fixation across a gap at an early stage. The use of HA clay to enhance the early stability of uncemented components may help to improve the functional outcome of total joint arthroplasty.