Subchondral insufficiency fracture of the femoral head (SIF) is a recently proposed concept. It is generally seen in elderly people, however, some young adults have also been reported to suffer from this fracture. The purpose of this study was to investigate the clinical results of a transtrochanteric anterior rotational osteotomy (ARO) performed in young adults with SIF. This study focused on young SIF cases (age range from 10 to 29 years). Five patients were diagnosed to have SIF at our institution and conservative treatment was initially performed. The symptoms resolved in 1 case while the other 4 cases showed progression of a collapse. In these 4 cases, ARO was performed, since the fractured area was located in the anterosuperior portion of the femoral head. The average age of the patients was 22 years (range, 16 to 29 years) at the time of surgery, consisting of 2 men and 2 women.Introduction
Methods
Subchondral insufficiency fracture of the femoral head (SIF) often occurs in osteoporotic elderly patients. Patients usually suffer from acute hip pain without any obvious antecedent trauma. Radiologically, a subchondral fracture is seen mainly in the superolateral portion of the femoral head. The T1-weighted magnetic resonance (MR) images show a low-intensity band in the subchondral area of the femoral head, which tends to be irregular, disconnected, and convex to the articular surface. This low-intensity band in SIF was histologically proven to correspond to the fracture line with associated repair tissue. Some cases of SIF resolve after conservative treatment, while others progress until collapse, thereby requiring surgical treatment. The prognosis of SIF remains unclear. This study investigated the risk factors that influence the prognosis of SIF based on the progression of the collapse. Between June 2002 and June 2008, seventeen patients diagnosed as SIF were included in this study. Sequential radiographs were evaluated for the presence of progression of the collapse. The clinical profiles, including the age, body mass index (BMI), follow-up period and Singh index were examined. The morphological characteristics of the low intensity band on the T1-weighted magnetic resonance images were also examined, with regard to the band length, band thickness and band length ratio; which is defined as a proportion of the band length to the weight-bearing portion of the femoral head.Introduction
Methods
Subchondral insufficiency fracture (SIF) needs to be differentiated from osteonecrosis. The purpose of this study was to evaluate the imaging and histopathological findings of patients 60 years or older with radiological evidence of subchondral collapse of the femoral head. We reviewed 77 consecutive hips in 56 patients aged 60 years or older, which showed subchondral collapse on radiographs. According to the shapes of low-intensity bands on T1-weighted images of magnetic resonance imaging (MRI), the patients were divided into 2 groups. Group A showed a concavity of the articular surface: characteristic appearances of osteonecrosis, and Group B showed an irregular convexity of the articular surface: characteristic appearances of SIF.Introduction
Methods
The objective of this study was to investigate the incidence of steroid-induced osteonecrosis (ON) among male and female rabbits. Forty-seven adult rabbits (male, n = 24; female, n = 23) were injected once intramuscularly into the right gluteus medius muscle with 20 mg/kg of methylprednisolone acetate. Hematological examinations were performed just before and at 1 and 2 weeks after the corticosteroid injection. Two weeks after the injection, both femora and humeri were histopathologically examined for the presence of ON, and the bone marrow fat cells were examined morphologically.Introduction
Methods
In Japan, idiopathic osteonecrosis of the femoral head (ONFH) is designated as a specified rare and intractable disease in patients for whom medical care is subsidized through the Specified Disease Treatment Research Program. Each patient is approved for the subsidy based upon a prefectural governmental review after filing an application together with a clinical research form documenting the patient's medical history, laboratory/clinical findings, and treatment. The purpose of this study was to conduct a fact-finding study of ONFH patients in the Fukuoka Prefecture based on clinical research forms of the Specified Disease Treatment Research Program. The distribution by gender and age of ONFH patients who filed an application for subsidy under this program between 1999 and 2008 was investigated on the basis of clinical research forms in the Fukuoka Prefecture. For comparative purposes, we also investigated the distribution by gender and age of ONFH patients who had a final diagnosis of ONFH at our institution during the past three years.Background
Methods
Transposition osteotomy of the acetabulum (TOA) was the first periacetabular osteotomy for the osteoarthritis hips due to acetabular dysplasia, in which the acetabulum was transposed with articular cartilage. TOA improves coverage of the femoral head to restore congruity and stability, and also prevent further osteoarthritis deterioration and induce regeneration of the joint. Many good clinical outcomes have been reported for such periacetabular osteotomies for osteoarthritis of the hips at an early stage. In contrast, the clinical outcome is controversial for those hips at an advanced stage, in which the joint space has partly disappeared. The purpose of this study was to investigate whether TOA is an appropriate option for treatment of osteoarthritis of the hips at the advanced stage by comparing with matched control hips at the early stage. Between 1998 and 2001, TOA was performed in 104 hips of 98 patients. Sixteen of 17 hips (94%) with osteoarthritis at the advanced stage were examined and compared with 37 matched control hips at the early stage. The mean age at the operation was 48(38–56) and the mean follow-up period was 88 (65–107) months. TOA corrected the acetabular dysplasia and significantly improved containment of the femoral head. No hips had secondary operations including THA. Clinical scores were also significantly improved in both of the groups. In the advanced osteoarthritis cases, there was a tendency for abduction congruity before transposition osteotomy of the acetabulum to reflect the clinical outcome. TOA is a promising treatment option for the advanced osteoarthritis of the hips as well as for those patients at the early stage when preoperative radiographs show good congruity or containment of the joint.
In recent years, the progressive technology of hemodialysis provides long-term survival for renal failure patients. On the other hand, avascular necrosis of the femoral head from the use of steroids or renal osteodystorophy or femoral neck fracture due to amyloid arthropathy have increased. In such cases, bipolar femoral head prosthesis (FHP) and total hip replacement (THR) are usually performed. But it is at risk of developing severe complications, such as early loosening or infection of the implant. The aim of this study is to evaluate the stability of the cementless stems in radiograms and clinical results after FHP or THR using three types cementless prosthesis in hemodialysis patients. The study included 14 patients (19 hips) on hemodialysis who underwent FHP or THR using three types cementless prosthesis at our institution between 1983 to 2005 and we could follow up at least two years. There were 8 women (11 hips) and 6 men (8 hips) with an average age of 43.9 years (range, 20–88). The average follow-up was 6.75 years. The average hemodialysis term was 10.5 years. Three types of hip prosthesis (7 stems were CLS, 6 stems were IMC, 6 stems were Duetto S-I) has been used for the treatment at our institution in the past. The initial diagnosis was avascular necrosis of the femoral head in 8 hips, femoral neck fracture in 5, osteoarthritis in 4 and amyloid arthropathy in two. We assessed at least 3° of varus-valgus deviation or at least 3 mm of subsidence as aseptic loosening of stems, and assessed radiolucent line and stress shielding of the stems in radiograms, also. As for clinical results, we measured postoperative infection rate and revision rate. Aseptic loosening of stems were identified in 3 hips (15.8%). Radiolucent lines were identified in 5%–26% of hips categolised by Gruen’s classification zone I-VII, although their zones differed according to the stem model. Stress shieldings were identified in 10 hips (53%), most of which were level 1, according to the criteria described by Engh et al. Infection rate and revision rate were 5.3% (1 hip) and it was a long-term hemodialysis patient. Several studies report, there is a high probability that early loosening of the stems is associated with amyloid deposition. We experienced early loosening of the stems in our case and considered prevention of amyloid deposition very important in improving the prognosis of the arthroplasty. We must follow carefully hemodialysis patients after an operation because their nutrition level is low and their bodies are compromised due to steroids use and their postoperative infection rate is high.
Several stems have been used for revision of total hip replacement (THR). Moreover, management of proximal femoral bone loss at the time of revision THR remains one of the challenges for hip surgeons. Recently, impaction bone grafting has been suggested to resolve this problem, but it is a demanding technique that results in frequent complications. We have used the Wagner self-locking stem with cancellous chip allograft for reconstruction of proximal femoral bone defect during revision surgery since 1992. This study evaluated the midterm results of using Wagner revision stem with bone allograft for femoral revision of THR. We could evaluate forty-one femoral revisions performed between 1992 and 2005 using Wagner revision stem with bone allograft. All patients had been followed for a minimum of three years with a mean follow-up of 8.6 years. Preoperative radiological femoral bone defects were assessed and classified by Gustillo’s classification. Subsidence of the stem was measured on radiograms taken immediately after revision surgery and again at the latest follow-up. Femoral component fixation was graded as radiographic ingrowth, fibrous stable, or unstable according to the criteria described by Engh et al. The incidence of surgical complications was examined. Allografts were assessed for incorporation into host bone as evidenced by trabecular bridging of the host-graft interface. A clear reduction in density or breakdown of the allograft was defined as bone resorption. Kaplan-Meier survival analysis was performed. The end point was revision because of mechanical loosening of the stem. Bone defects were classified as: 10 hips type I, 20 hips type II, and 7 hips type III and 4 hips were a periprosthetic fracture. Subsidence was measured at the time of last follow-up in six hips (3, 3, 12, 16, 21, 30 mm). At the latest follow-up 37 of 41 stems were stable. Allograft incorporation could clearly be observed in the proximal femoral bone defects of 31 stems. Three stems were defined as showing bone resorption. Surgical complications included 11 intraoperative fractures, two femoral shafts were perforated during reaming, one dislocation postoperatively, and 3 greater trochanter pseudoarthroses. There was one deep infection, and these cases were excluded from survivorship analysis. One unstable stem and one stem with infection had to be revised. Kaplan-Meier survival was 97.1 % at 10 years. Wagner self-locking stem with allograft for reconstruction for proximal femoral bone defect in revision surgery is a beneficial procedure. However, because there is a high incidence of intraoperative fractures, surgery should be performed carefully.
Combined anteversion (CA) is defined as the sum of the anteversions of acetabular and femoral components. In this study, we determined the appropriate CA in a variety of femoral versions using a total hip arthroplasty model. In addition, we also examined the usefulness of a changeable neck to improve range of hip motion in these cases. Using a THA model, the range of motion (ROM) was tested in various CA values obtained by changing the anteversion of a cup in six increments after setting the femoral anteversion to 20° or 60° anteversion and 20° retroversion. The angle of the changeable neck was changed in 11 increments of 5°. To evaluate stability, the range of internal rotation at 90° flexion, the external rotation at 0° extension, and the range flexion was measured when any impingement occurred prior to dislocation. We defined the required ROM that met 40° internal rotation, 30° external rotation, and 110° flexion. In normal 20° anteversion group, the required ROM was achieved with CA between 30° and 50° without using any changeable necks. In excessive anteversion 60° group, the range of external rotation was less than 10° even when the acetabular component was set 10° retroverted, because of the bone impingement between the greater trochanter and the posterior acetabulum. When 25° retroverted changeable neck was used, ROM improved to 30° external rotation and satisfied the required ROM. In 20° retroversion group, the internal rotation angle was 31° even when the acetabular component was opened 35° anteverted, because of anterior neck-liner impingement. When 25° anteverted changeable neck was used, ROM improved to 39° internal rotation and 130° flexion. In cases with normal anteversions, the required ROM can be achived by adjusting CA. In cases with excessive anteversion or retroversion, there was a limitation of the CA adjustment. The use of changeable necks allows for further improvement of ROM by compensating femoral anteversions.
Treating Crowe type 3 or 4 of hips tends to be technically difficult when performing total hip arthroplasty (THA) due to the severely dysplastic acetabulum and proximal femur in addition to a high dislocation of the hip. Since the socket is limited to being placed at the original hip center, a femoral shortening osteotomy is often required in order to prevent neurovascular problems. This osteotomy will need the stability of the femoral stem with both the proximal and the distal femoral bones. We used the modular S-ROM stem, which has a valuable proximal structure and a distal flute structure to stabilize the stem with the proximal and distal femoral fragments. The purpose of this study was to report the clinical and radiographic results of the primary THA with a shortening osteotomy while also using the S-ROM prosthesis. Between 1994 and 2004, primary THA using the S-ROM prosthesis was performed on 7 hips in 6 cases (1 male, 5 females). Crowe type 3 or 4 was observed in one and 6 hips, respectively. The mean age at operation was 56 years old (range 51~60). The mean follow-up period was 41 months (range 24~56 months). Four hips had previously undergone a subtrochanteric valgus osteotomy. All hips underwent a step-cut femoral osteotomy at the proximal metaphysis for the shortening and/or correction of angulations with on-lay chip bone grafts. All of the used stems were straight type. The clinical outcome was evaluated using the clinical scoring system of hip joints established by the Japanese Orthopaedic Association (JOA). According to a 100 point scale, pain was determined to be 40, ROM was 20, gait was 20 and ADL was 20. No hips had undergone any revision surgery as of the most recent follow-up. Union was achieved at the osteotomy site in all hips. Neither osteolysis nor a loosening of the implant was radiographically observed. The mean JOA score before THA and at the last follow-up was 41 (31–48) and 81 (62–91) points, respectively. The mean postoperative days to start full weight bearing was 53 days (range 49~70). In two cases (28%), a procedure using circular wiring was performed to treat a crack in the proximal femur. The S-ROM prosthesis was thus found to be useful for primary THA with a shortening metaphyseal femoral osteotomy for hips in patients with Crowe type 3 or 4 developmental dysplasia.
Management of severe acetabular bone loss at the time of revision total hip replacements (THR) remains has been one of the greater challenges for hip surgeon. Recently, many methods of acetabular reconstruction have been described and various materials are used for supplement of the bone stock deficiency in acetabular revision THR. The purpose of this study was to evaluate the midterm results of the using support ring with bone allografts in acetabular revision THR.
From 1990 to 2005, forty-six acetabular revisions using supporting ring with bone allografts were performed at our institution. All patients were followed up for a minimum of three years with a mean follow-up of 7.5 years. Pre-operative radiological acetabular bone defects were assessed and classified by author’s classification (Itoman’s classification). Radiological analysis involved a general qualitative evaluation. The position of the acetabular reinforcement ring was measured on radiograms, taken immediately after revision surgery and again at the time of last follow-up. Using a MEM template, cranio-central migration and cup inclination angle were measured. Kaplan-Meier survivorship analysis was performed. The end point was revision because of mechanical loosening of the acetabular implant. We used thirty-six Ganz rings, six Müller rings, three Kerboull T-plate and two Burch-Schneider anti-protrusion cages. The acetabular bone defects were classified as: 10 hips Type B (central defect), 9 hips Type C (cranial defect), 27 hips Type D (cranial-central defect). Migration of acetabular component was defined as a change of >
5mm in the cranial or central direction of the cup or a change in the cup inclination angle of >
5° at the time of last follow-up. All the Eleven acetabular components which had defined as loose were Type D. One acetabular component was revised because of mechanical loosening, four were revised because of infection, and one was broken polyethylene liner. Kaplan-Meier survivorship of these reconstructions was 96.2 % at 10 years. Allograft reconstruction of acetabular bone defect in revision total hip replacement is beneficial procedure. The remaining pelvic bone is usually in poor condition, therefore, it is necessary to ensure primary fixation with the reinforcement ring with bone allografts.
