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?

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.

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.

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.

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).

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.