Anterolateral femoral bowing and loss of thigh muscle are associated with occurrence of atypical femoral fracture: Effect of failed tension band mechanism in mid-thigh.

BACKGROUND: The purpose of this study was to characterize anterolateral bowing of the femur using X-rays and muscular atrophy in the mid-thigh using computed tomography (CT) in patients with atypical femoral fractures (AFFs). We then compared the results with those of an intertrochanteric fracture to understand whether these measures act as causative factors of AFFs. METHODS: From January 2009 to December 2015, 37 patients with complete AFF and 12 patients with incomplete AFF were enrolled in this study. Lateral femoral bowing, anterior femoral bowing, cross-sectional area (CSA), and attenuation coefficient of thigh muscles in the AFF group are measured and compare with those in the intertrochanteric fracture group. RESULTS: Lateral and anterior femoral bowing in the AFF group were significantly higher than those in the intertrochanteric fracture group. The level of fracture was found to be significantly associated with lateral and anterior femoral bowing (r = 0.569, r2 = 0.324, p < 0.001; r = -0.530, r2 = 0.281, p < 0.001, respectively). Total CSA and CSA of anterior and medial compartments were significantly lower in the AFF group (p < 0.05). The attenuation coefficient of the total thigh muscle and all three compartments in the AFF group were significantly lower than those in the intertrochanteric fracture group (p < 0.05). CONCLUSIONS: This study demonstrated that anterolateral femoral bowing and loss of thigh muscle were highly associated with the occurrence of AFFs.

The reliability and accuracy of measuring anteversion of the acetabular component on plain anteroposterior and lateral radiographs after total hip arthroplasty.

There is no single standardised method of measuring the orientation of the acetabular component on plain radiographs after total hip arthroplasty. We assessed the reliability and accuracy of three methods of assessing anteversion of the acetabular component for 551 THAs using the PolyWare software and the methods of Liaw et al, and of Woo and Morrey. All measurements of the three methods had excellent intra- and inter-observer reliability. The values of the PolyWare software, which determines version of the acetabular component by edge detection were regarded as the reference standard. Although the PolyWare software and the method of Liaw et al were similarly precise, the method of Woo and Morrey was significantly less accurate (p < 0.001). The method of Liaw et al seemed to be more accurate than that of Woo and Morrey when compared with the measurements using the PolyWare software. If the qualified lateral radiograph was selected, anteversion measured using the method of Woo and Morrey was considered to be relatively reliable.

Polymorphism in interleukin-6 gene is associated with bone mineral density in patients with adolescent idiopathic scoliosis.

Low bone mass and osteopenia have been described in the axial and peripheral skeleton of patients with adolescent idiopathic scoliosis (AIS). Recently, many studies have shown that gene polymorphism is related to osteoporosis. However, no studies have linked the association between IL6 gene polymorphism and bone mass in AIS. This study examined the association between bone mass and IL6 gene polymorphism in 198 girls with AIS. The polymorphisms of IL6-597 G-->A, IL6-572 G-->C and IL6-174 G-->A and the bone mineral density in the lumbar spine and femoral neck were analysed and compared with their levels in healthy controls. The mean bone mineral density at both sites in patients with AIS was decreased compared with controls (p = 0.0022 and p = 0.0013, respectively). Comparison of genotype frequencies between AIS and healthy controls revealed a statistically significant difference in IL6-572 G-->C polymorphism (p = 0.0305). There was a significant association between the IL6-572 G-->C polymorphism and bone mineral density in the lumbar spine, with the CC genotype significantly higher with the GC (p = 0.0124) or GG (p = 0.0066) genotypes. These results suggest that the IL6-572 G-->C polymorphism is associated with bone mineral density in the lumbar spine in Korean girls with AIS.

Posterior lumbar interbody fusion for adult isthmic spondylolisthesis: a comparison of fusion with one or two cages.

Between March 2000 and February 2006, we carried out a prospective study of 100 patients with a low-grade isthmic spondylolisthesis (Meyerding grade II or below), who were randomised to receive a single-level and instrumented posterior lumbar interbody fusion with either one or two cages. The minimum follow-up was for two years. At this stage 91 patients were available for review. A total of 47 patients received one cage (group 1) and 44 two cages (group 2). The clinical and radiological outcomes of the two groups were compared. There were no significant differences between the two groups in terms of post-operative pain, Oswestry Disability Score, clinical results, complication rate, percentage of post-operative slip, anterior fusion rate or posterior fusion rate. On the other hand, the mean operating time was 144 minutes (100 to 240) for patients in group 1 and 167 minutes (110 to 270) for those in group 2 (p = 0.0002). The mean blood loss up to the end of the first post-operative day was 756 ml (510 to 1440) in group 1 and 817 ml (620 to 1730) in group 2 (p < 0.0001). Our results suggest that an instrumented posterior lumbar interbody fusion performed with either one or two cages in addition to a bone graft around the cage has a low rate of complications and a high fusion rate. The clinical outcomes were good in most cases, regardless of whether one or two cages had been used.

Posterior lumbar interbody fusion and posterior instrumentation in the surgical management of lumbar tuberculous spondylitis.

There are few reports of the treatment of lumbar tuberculous spondylitis using the posterior approach. Between January 1999 and February 2004, 16 patients underwent posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation. Their mean age at surgery was 51 years (28 to 66). The mean follow-up period was 33 months (24 to 48). The clinical outcome was assessed using the Frankel neurological classification and the Kirkaldy-Willis criteria. On the Frankel classification, one patient improved by two grades (C to E), seven by one grade, and eight showed no change. The Kirkaldy-Willis functional outcome was classified as excellent in eight patients, good in five, fair in two and poor in one. Bony union was achieved within one year in 15 patients. The mean pre-operative lordotic angle was 27.8 degrees (9 degrees to 45 degrees ) which improved by the final follow-up to 35.8 degrees (28 degrees to 48 degrees ). Post-operative complications occurred in four patients, transient root injury in two, a superficial wound infection in one and a deep wound infection in one, in whom the implant was removed. Our results show that a posterior lumbar interbody fusion with autogenous iliac-bone grafting and pedicle screw instrumentation for tuberculous spondylitis through the posterior approach can give satisfactory results.

Pineal gland metabolism in patients with adolescent idiopathic scoliosis.

The scoliosis observed in chickens after pinealectomy resembles that seen in humans with an adolescent idiopathic scoliosis, suggesting that melatonin deficiency may be responsible. However, to date there have been no studies of pineal gland glucose metabolism in patients with adolescent idiopathic scoliosis that might support this hypothesis. We examined the excretion of urinary 6-sulfatoxyl-melatonin as well as the glucose metabolism of the pineal gland in 14 patients with an adolescent idiopathic scoliosis and compared them with those of 13 gender-matched healthy controls using F-18 fluorodeoxyglucose brain positron emission tomography. There was no significant difference in the level of urinary 6-sulfatoxyl-melatonin or pineal gland metabolism between the study and the control group. We conclude that permanent melatonin deficiency is not a causative factor in the aetiology of adolescent idiopathic scoliosis.

Posterior lumbar interbody fusion with an autogenous iliac crest bone graft in the treatment of pyogenic spondylodiscitis.

There are few reports on the treatment of pyogenic lumbar spondylodiscitis through the posterior approach using a single incision. Between October 1999 and March 2003 we operated on 18 patients with pyogenic lumbar spondylodiscitis. All underwent posterior lumbar interbody fusion using an autogenous bone graft from the iliac crest and pedicle screws via a posterior approach. The clinical outcome was assessed using the Frankel neurological classification and the criteria of Kirkaldy-Willis. Under the Frankel classification, two patients improved by two grades (C to E), 11 by one grade, and five showed no change. The Kirkaldy-Willis functional outcome was excellent in five patients, good in ten and fair in three. Bony union was confirmed six months after surgery in 17 patients, but in one patient this was not achieved until two years after operation. The mean lordotic angle before operation was 20 degrees (-2 degrees to 42 degrees ) and the mean lordotic angle at the final follow-up was 32.5 degrees (17 degrees to 44 degrees ). Two patients had a superficial wound infection and two a transient root injury. Posterior lumbar interbody fusion with an autogenous iliac crest bone graft and pedicle screw fixation via a posterior approach can provide satisfactory results in pyogenic spondylodiscitis.

Effects of peripheral benzodiazepine receptor ligands on proliferation and differentiation of human mesenchymal stem cells.

The peripheral benzodiazepine receptor (PBR) has been known to have many functions such as a role in cell proliferation, cell differentiation, steroidogenesis, calcium flow, cellular respiration, cellular immunity, malignancy, and apoptosis. However, the presence of PBR has not been examined in mesenchymal stem cells. In this study, we demonstrated the expression of PBR in human bone marrow stromal cells (hBMSCs) and human adipose stromal cells (hATSCs) by RT-PCR and immunocytochemistry. To determine the roles of PBR in cellular functions of human mesenchymal stem cells (hMSCs), effects of diazepam, PK11195, and Ro5-4864 were examined. Adipose differentiation of hMSCs was decreased by high concentration of PBR ligands (50 microM), whereas it was increased by low concentrations of PBR ligands (<10 microM). PBR ligands showed a biphasic effect on glycerol-3-phosphate dehydrogenase (GPDH) activity. High concentration of PBR ligands (from 25 to 75 microM) inhibited proliferation of hMSCs. However, clonazepam, which does not have an affinity to PBR, did not affect adipose differentiation and proliferation of hMSCs. The PBR ligands did not induce cell death in hMSCs. PK11195 (50 microM) and Ro5-5864 (50 microM) induced cell cycle arrest in the G(2)/M phase. These results indicate that PBR ligands play roles in adipose differentiation and proliferation of hMSCs.

The role of inducible nitric oxide synthase in aseptic loosening after total hip arthroplasty.

We collected 16 samples of the membrane which surrounds loose hip prostheses from patients undergoing revision operations for aseptic loosening. To serve as the control group, samples of the synovial tissue and the fibrous capsular tissue were collected from 11 patients undergoing primary hip arthroplasties. Analyses of the expression levels of inducible nitric oxide synthase (iNOS), tumour necrosis factor-alpha (TNF-alpha), and cytosolic phospholipase A2 (cPLA2) mRNAs were performed by a reverse transcription polymerase chain reaction, and the content of nitrite was measured by the Griess reaction using sodium nitrite as the standard. The expression levels of iNOS, TNF-alpha, and cPLA2 mRNAs in the membranes were significantly higher than those in the control samples (p < 0.05). The expression levels of iNOS mRNA and the nitrite content in the membranes significantly correlated with those of TNF-alpha and cPLA2 mRNAs, respectively. In addition, the expression levels of iNOS, TNF-alpha, and cPLA2 mRNAs were significantly higher in membranes from cementless than in those from cemented implants (p < 0.05). Our results suggest that the expression levels of iNOS, TNF-alpha, and cPLA2 mRNAs in the membranes are regulated by closely-related mechanisms and that these have a significant role in aseptic loosening.

Natural progress of a bone scan after cementless hydroxyapatite-coated total hip arthroplasty.

To establish the natural progress pattern of postoperative bone uptake, a periprosthetic quantitative technetium-99m methylene diphosphonate scintiscan was done on 80 asymptomatic hips (62 patients) with uncomplicated cementless hydroxyapatite-coated total hip arthroplasties and 20 healthy control hips (10 subjects) without previous surgery. The patients were studied in eight groups at scheduled intervals of 1 to 48 months. There were 10 hips in each group. The measurement of bone uptake in the healthy untreated control group indicated that the uptake ratio in the proximal femur was physiologically higher in the metaphyseal area than in the diaphyseal area and the uptake ratio in the acetabulum appeared to be much higher than that of the proximal femur. In the patient group, the uptake ratio around the femoral stem area and the acetabular cup area showed a statistically significant decrease between 1 and 3 months after surgery and changed little after 3 months. Comparing the result of the patient group with that of the healthy untreated control group, the uptake ratio decreased much faster in the hydroxyapatite-coated metaphyseal zone than in the noncoated diaphyseal zone of the femoral stem area. In the acetabular cup area, the uptake ratio decreased fast, as in the hydroxyapatite-coated metaphyseal zone of the femoral stem area. Based on these clinical results, a quantitative bone scan may be a helpful diagnostic procedure for evaluating postoperative progress when used in conjunction with clinical symptoms and radiologic examinations.

Catastrophic progression of the disassembly of a modular acetabular component.

Disassembly of a metal-backed modular acetabular component used for total hip arthroplasty is becoming more common. If the acetabular disassembly is detected early, the revision procedures are relatively simple. In the case of long-term sustained disassembly, however, there are more complicated problems, and more difficult revision procedures are needed. We report a case of long-term sustained disassembly of a modular acetabular component in order to alert orthopaedic surgeons of the catastrophic progression to more severe complications, such as the loosening of the metal-acetabular component and severe acetabular osteolysis.

Avascular necrosis after fracture-separation of the distal end of the humerus in children.

Fracture-separation of the distal end of the humerus in children has been reported infrequently, and may be misdiagnosed as a fracture of the condyle or a traumatic dislocation of the elbow. We discuss eight cases of a seldom reported complication following fracture-separation of the distal end of the humerus. This complication consists of dissolution of the trochlea within three to six weeks postinjury and a defect of the medial or central part of the condyle that develops later. The fractures were severely displaced fracture-separation of the distal end of the humerus with large medial or lateral metaphyseal fragment, but initially misdiagnosed as a fracture of the medial, lateral condyle or a traumatic dislocation of the elbow in six of eight cases. We performed open reduction in six cases because of initial misdiagnosis or because of difficulty in satisfactory closed reduction. We speculated that this complication is due to avascular necrosis of the distal end of the humerus, and that fracture-separation of the distal end of the humerus is more common than reported.