Cationic polymer-mediated genetic transduction into cultured human chondrosarcoma-derived HCS-2/8 cells

The usefulness of three types of cationic polymer, i.e., degraded polyamidoamine (PAMAM) dendrimer (SuperFect Transfection Reagent; Oiagen), linear polyethylenimine (PEI; ExGen 500; Euromedex), and branched PEI in gene delivery into chondrocytes was examined comparatively. A plasmid vector containing the Escherichia coli LacZ (pSES.beta) was combined with one of the three cationic polymers at various molar ratios and the resultant complex (polyplex) was used to transduce a human chondrocyte-like cell line, HCS-2/8. Gene expression was evaluated by an O-nitrophenyl beta-D-galactopyranoside (ONPG) assay and by staining with 0.05% 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-gal; Nacalai Tesque). The ONPG assay showed that the highest delivery rate was achieved when 2microg of pSES.beta was combined with either 21 microg of dendrimer, 1.7microg of linear PEI, or 2.0microg of branched PEI. At the same DNA/polymer ratios, the proportions of X-gal-stained cells were also the highest (31.3 +/- 7.5%, 30.3 +/- 9.0%, and 8.3 +/- 3.1%, respectively). LacZ expression reached the highest level 3 days after the dendrimer-mediated transduction, and gradually declined, returning to the background level on day 14. Possible cytotoxicity was examined by trypan blue staining and phase contrast microscopic observations. Neither cytotoxicity nor morphological change was induced at the optimal dose of each polymer. The cationic polymers, particularly the degraded dendrimer and linear PEI, would be a useful nonviral vector for gene delivery to cells of chondrocytes.

Osteonecrosis of the femoral head that developed after long-term topical steroid application

This is a report of a 52-year-old man who developed osteonecrosis of the femoral head (ONF) following long-term application of steroid for facial eczema. Before hip pain appeared, the patient had applied 2-3g/day of 0.05% clobetasol propionate for 2 years and 10 months. This steroid is classified as being in the strongest category. ONF was diagnosed based on radiographic and magnetic resonance imaging findings, and the patient received surgical treatment for both hips. ONF was also confirmed by pathological examination of a specimen obtained from the right femoral head during surgery. Because there were no risk factors for ONF besides topical steroid application, this case was considered as ONF associated with topical steroid. Even when steroids are for external use, their dosage and administration should be monitored, and the risk of ONF should also be considered.

Electrophysiological course of uraemic neuropathy in haemodialysis patients

The objective of this study was to confirm electrophysiologically both the presence and course of uraemic neuropathy in haemodialysis patients. Nerve conduction studies of the lower extremities were done in 70 haemodialysis patients and 20 normal volunteers. Compared with that in normal volunteers, the distal motor latency in the tibial nerve of patients was prolonged significantly (p<0.05), and the minimal F wave latency in the tibial nerve was also prolonged significantly (p<0.05). Motor conduction velocity in the tibial nerve was reduced significantly (p<0.05), and sensory nerve conduction velocity in the medial plantar nerve also was reduced significantly (p<0.05). These results suggest the presence of uraemic neuropathy in haemodialysis patients. Twenty patients were investigated by a follow up study five years later. Parameters from F wave conduction studies, which were thought to be the most useful in the evaluation of neuropathy, showed no significant differences between the initial and follow up trials. These observations suggest that uraemic neuropathy does not progress during haemodialysis. These results also suggest that most haemodialysis patients showed electrophysiological evidence of uraemic neuropathy, but no remarkable electrophysiological change in uraemic neuropathy during haemodialysis was recognised.

Bone reaction induced by femoral stem of titanium alloy endoprosthesis for malignant bone tumors at the distal femur

We demonstrated radiological evaluations after limb salvage surgery with an uncemented titanium endoprosthesis possessing a rotating hinge-type knee joint for 7 patients with malignant bone tumors at the distal femur. Although radiographically, cortical hypertrophy and new bone formation at the junction between implant and cortex appeared in all cases, there was a small quantity of subsidence of the implant in all cases. Loosening of the stem was found in 2 patients at 4 and 9 years after surgery. However, after revision surgery, the function restored as before. The latest average functional score according to the system of the International Society of Limb Salvage was good, being 73%.

Prediction of mechanical properties of healing fractures using acoustic emission

The objective of this study was to develop a non-destructive method for monitoring fracture healing with acoustic emission (AE). Experimentally produced fractures of the rat femur were tested in tension and in torsion at 4, 6, 8 and 12 weeks after fracture. AE signals were monitored during these mechanical tests. The values for load and torque at the initiation of the AE signal were defined as new mechanical parameters. The apparent density and ash density of the fracture site were also measured at each time period. Tensile strength, tensile stiffness, maximum torque and torsional stiffness of the fracture site increased with time. The AE signal was detected before complete specimen failure. Load and torque for initiation of AE increased proportionally with increasing mechanical properties. The mineral density, however, reached a plateau at 8 weeks, when callus mechanical strength was approximately 50% of control. Load for initiation of AE was strongly correlated with the strength (r = 0.98), stiffness (r = 0.88), and failure strain (r = -0.63) of the callus. Torque for initiation of AE was highly correlated with the maximum torque (r = 0.95) and torsional stiffness (r= 0.93) of the callus. The findings of the present study indicated that some mechanical properties of healing fractures could be estimated by monitoring AE signals.

Effect of acetabular cup position and orientation in cemented total hip arthroplasty

Long-term clinical results of total hip arthroplasty for patients with developmental acetabular dysplasia of the hip have been reported, but placement of the femoral head center or cup orientation remains controversial, especially with a severe anterolateral shallow acetabulum or dislocated femoral head. Results of 41 Müller and 34 Harris Design 2 cemented total hip arthroplasties were evaluated for developmental dysplasia of the hip. The femoral head center and acetabular cup inclination angle were measured from the interteardrop line. Linear wear and wear direction were measured using the Livermore technique. The best position of the femoral head center was less than 35 mm vertically from the interteardrop line and 25 mm laterally from the teardrop. Femoral head center analysis showed that hips with the cup in a lateral and superior cup position all were revised, but a superior and medial position combined with a cup inclination angle less than 40 degrees did not require revision. Hips with a cup inclination angle more than 45 degrees had superior and lateral penetration patterns of the polyethylene. However, hips with an inclination angle less than 35 degrees and medial placement had medial head penetration patterns. With these all-polyethylene monolithic cemented cups, regardless of the femoral head diameter or cup thickness, better long-term results occurred with a cup inclination angle of 40 degrees or less and medial position of the cup.

Characteristic features of the acetabular labrum in healthy children

Radial magnetic resonance images of the acetabular labrum were obtained on 40 hips of healthy children. There were no right-left or male-female differences. In children aged 11 years or younger, the labrum on the antero-superior weightbearing portion was triangular in shape, and there was an insular-shaped or linear high-intensity area inside; on the mid-superior portion, the labrum appeared as a regular triangular, low-intensity area; and on the postero-superior portion, it was flat. In children aged 12 and 13 years, the shape of the labrum in each portion was similar to that of the younger children, but the high signal intensity area on the antero-superior portion appeared less frequently. The size of the labrum relative to the femoral head was greater in younger children.

Primary total knee arthroplasty for supracondylar/condylar femoral fracture in osteoarthritic knees

Supracondylar or condylar femoral fractures require extended treatment and often result in loss of knee range of motion. We present 3 cases in which femoral fractures and preexisting painful knees secondary to osteoarthritis were treated using total knee arthroplasty with a stemmed femoral implant. The patients were all women aged 83, 84, and 87 years old. All fractures united within 3 months, and the patients could walk with 1 cane within 2 months. Primary total knee arthroplasty should be considered as a treatment for supracondylar/condylar femoral fractures in osteoarthritic knees.

Computed tomography measurement of the surgical and clinical transepicondylar axis of the distal femur in osteoarthritic knees

To assess rotational alignment of the distal femur, 2 types of transepicondylar axes have been used in the literature. We compared surgical and clinical epicondylar axes in the measurement of rotational alignment of the femur in planning for total knee arthroplasty (TKA). We examined 48 patients who were candidates for TKA. Computed tomography images of both knees were obtained, and condylar twist angle and posterior condylar angle were measured. The medial sulcus was detected in only 33 knees. The more severe the grade of osteoarthritis, the more difficult it was to detect the medial sulcus. The most prominent point of medial epicondyle was detectable in all knees. We recommend the use of the clinical epicondylar axis in computed tomography measurement in selective planning for TKA.

Blood flow and blood volume in the femoral heads of healthy adults according to age: measurement with positron emission tomography (PET)

OBJECTIVE

To deepen understanding of hemodynamics in the femoral head, i.e., the essential factor in clarifying pathogenesis of hip disorders, this study examined blood flow and blood volume in the femoral heads of healthy adults, and their changes with age, by using positron emission tomography (PET).

METHODS

In 16 healthy adult males (age: 20-78 years old, mean age: 42 years), blood flow was measured by means of the H2(15)O dynamic study method, and blood volume was measured by means of the (15)O-labeled carbon monoxide bolus inhalation method.

RESULTS

Blood flow was 1.68-6.47 ml/min/100 g (mean +/- SD: 3.52 +/- 1.2), and blood volume was 1.67-6.03 ml/100 g (mean +/- SD: 3.00 +/- 1.27). Blood flow significantly decreased (p < 0.01) with age, and blood volume significantly increased (p < 0.05).

CONCLUSION

PET was useful in the measurement of blood flow and blood volume in the femoral heads. With age, physiological hemodynamic changes also increased in femoral heads.

Sympathetic skin response evoked by respiratory stimulation as a measure of sympathetic function

OBJECTIVES

To compare respiratory and electrical methods of evoking a sympathetic skin response (SSR).

METHODS

SSRs evoked by both electrical and respiratory stimulation were recorded from the palms of 47 healthy volunteers. Expiration and inspiration were used as separate stimuli. The correlation coefficients between the amplitude and latency of the SSR from the palm electrodes and the various components of heart rate variability were calculated.

RESULTS

Waveform patterns of the SSRs obtained from electrical stimulation showed varied responses to and habituation to this type of stimulation. On the other hand, no subjects showed a phase change in SSR waveform patterns between the first and last expiratory stimuli. The potentials recorded after expiratory stimulation had significantly greater amplitudes than those recorded after electrical stimuli. The low frequency component of heart rate variability induced by expiratory stimulation was significantly greater than that induced by electrical stimulation. The SSR may also correlate strongly with the change of respiratory rate since a more rapid pressure change occurs during expiratory movement than during inspiratory movements.

CONCLUSIONS

The SSR evoked by expiratory stimulation is more reliable than either electrical stimulation or inspiratory stimulation for determining sympathetic function.

[Postoperative rupture of abdominal aortic aneurysm in patients with ischemic heart disease and other organ disease]

We experienced two cases of rupture of an abdominal aortic aneurysm during the early postoperative period of coronary artery bypass grafting (CABG). A 71-year-old man on hemodialysis (HD) was diagnosed with ischemic heart disease (IHD) and abdominal aortic aneurysm (AAA) of 70 mm in size. After CABG, he developed symptoms of acute pancreatitis and died of rupture of AAA on the 12th postoperative day. A 74-year-old man with early gastric cancer was diagnosed with IHD and AAA of 70 mm. After CABG and gastrectomy, he died of rupture of AAA due to anticoagulant therapy on the 3rd postoperative day. One-stage operation should be performed in patients with IHD, AAA more than 60 mm in size and other organ disease. It is important to control blood pressure and anticoagulant therapy appropriately during the early postoperative period when graft replacement for AAA is not performed simultaneously. Careful observation is required to establish the differential diagnosis of acute pancreatitis and impending rupture of AAA in patients on HD.

Intradiscal solid phase displacement as a determinant of the centripetal fluid shift in the loaded intervertebral disc

STUDY DESIGN

The movement of cross sections of the monofilament nylon threads inserted into the axially loaded intervertebral disc was traced with magnetic resonance imaging (MRI). This technique allowed the observation of the sequential solid phase displacement of the loaded intervertebral disc.

OBJECTIVES

To clarify sequential solid phase displacement of the axially loaded intervertebral disc to elucidate the cause of centripetal fluid shift within a disc.

SUMMARY OF BACKGROUND DATA

We already have reported that there is a centripetal fluid shift within the axially loaded intervertebral disc during the early phase of loading. We assumed that there should be an elaborate intradiscal matrix displacement that generates a pressure gradient within the disc to cause a centripetal fluid shift.

METHODS

Thirteen freshly obtained bovine caudal intervertebral discs were prepared. Three to five monofilament nylon threads were inserted into each disc in the anterior-posterior direction to trace the intradiscal solid phase displacement on the midcoronal MR images. Sequential displacement of the disc matrix was recorded during a 294 N axial loading.

RESULTS

Relatively large centrifugal expansion at the inner layer of the anulus fibrosus compared with less centrifugal expansion of the outer anulus fibrosus was observed in accord with gradual creep of the disc thickness.

CONCLUSIONS

The uneven displacement of the intradiscal solid phase observed in the present study expels the fluid phase from the inner anulus fibrosus, thus resulting in accumulation of fluid phase in the nucleus pulposus. The present study suggests the presence of a mechanism that retains water within the normal intervertebral disc, in spite of an external load, because it forms a water-abundant nucleus pulposus, which is surrounded by an anulus fibrosus with decreased water permeability caused by fluid loss. A more detailed analysis is required to clarify topographic volumetric changes within the disc.

Hyaluronan suppressed nitric oxide production in the meniscus and synovium of rabbit osteoarthritis model

Nitric oxide (NO) plays an important role in cartilage degeneration, and NO donors induce meniscus degeneration and synovium inflammation. This study evaluated the effect of intraarticular injections of hyaluronan (HA) on NO production in meniscus and synovium using an experimental osteoarthritis (OA) model. Thirty-six New Zealand white rabbits underwent unilateral anterior cruciate ligament transection (ACLT), and were divided into three groups. Four weeks after ACLT, the HA group started to receive intraarticular HA injections once a week for 5 weeks; the vehicle group started to receive the carrier of HA; and the no injection group, no treatment. All ACLT knees were harvested at the 9th week. Meniscus and synovium sections were examined by immunohistochemistry for nitrotyrosine. The pieces of these two tissues were cultured for 24 h. Culture supernatants were analyzed for nitrite concentration. The amount of NO produced by the meniscus was much larger than that produced by the synovium. NO productions in the meniscus and synovium of the HA group were significantly lower than those of the other groups. The results suggest that the inhibition of NO production in meniscus and synovium might be a part of the mechanism of the therapeutic effect of HA on OA.

Non-traumatic osteonecrosis of the femoral head treated with transtrochanteric anterior rotational osteotomy combined with vascularized iliac bone grafting

A 49-year-old Japanese man who had non-traumatic osteonecrosis of the femoral head with a wide necrotic lesion received transtrochanteric anterior rotational osteotomy combined with vascularized iliac bone grafting. After the bone graft (6 x 1.5 cm) was collected, the femoral head was anteriorly rotated by 90 degrees. A bone tunnel of 1.2 cm in diameter was prepared on the necrotic lesion adjacent to the intact area from the anterior part of the femoral neck to inside the femoral head. The bone graft was trimmed to the size of this bone tunnel, and inserted up to immediately below the articular surface. In the monitoring using T1-weighted magnetic resonance imaging (MRI), the low signal-intensity area between the bone graft and intact area had disappeared, and a high signal-intensity area on the weight-bearing portion of the femoral head had extended. With modifications on the insertion point of the bone graft, transtrochanteric anterior rotational osteotomy combined with vascularized iliac bone graft would be a useful means to preserve the femoral head in large non-traumatic osteonecrosis of the femoral head.

A 10- to 13-year follow-up study of Harris-Galante type prosthesis in total hip arthroplasty

Long-term clinical results of Harris-Galante type prosthesis in total hip arthroplasty (THA) were evaluated in 27 hip joints of 25 patients (2 men and 23 women). Seventeen joints also received bone grafting on the acetabulum. Mean follow-up period was 11 years and 3 months. Clinical out-come was evaluated using the hip score of the Japanese Orthopaedic Association, and the score was good and stable during the monitoring period. Implant stability, bone changes around the implant, and the occupancy rate of the stem in the medullary space were radiologically examined. As a result of stem, there was subsidence in 3 joints and loosening in 6. There were no cases of cup loosening. A pedestal was found in 12 joints, and 4 of them which were associated with a radiopaque line had stem loosening. Among the 21 joints without loosening, 8 had a pedestal but they were not associated with a radiopaque line. The 2 joints which developed osteolysis did not have loosening. Stem loosening was related to the stem occupancy rate in the distal part of the medullary cavity. Postoperative stem occupancy rate could be an important indicator for long-term clinical results. Stems for cementless THA should be designed to have a high occupancy rate in the distal part, and stems should also be carefully chosen to meet individual differences.

Bombelli's valgus-extension osteotomy for osteoarthritis due to acetabular dysplasia: results at 10 to 14 years

Severe osteoarthritis due to acetabular dysplasia (n = 17) was treated with valgus-extension osteotomy, and the patients' clinical outcomes 10-14 years after operation were evaluated according to clinical factors (Japanese Orthopaedic Association hip score; JOA score) and by roentgenography. The mean JOA score 10 years or later had improved by 22 points compared with the preoperative score. On roentgenography, joints which had preoperative roof osteophyte had better postoperative formation of roof osteophyte. The JOA score was higher in the 12 joints which had osteophyte 5 mm or longer than in those joints with osteophyte that was 5 mm or shorter. Postoperative joint space widening occurred in 15 joints (88.2%) 3-6 months postoperatively, and it reached the maximum at 3-5 years. In patients who had a large bone cyst in the femoral head preoperatively, the cyst collapsed, and deformation of femoral head occurred after operation, but remodeling of the joint surface occurred naturally and the congruity improved. In the 6 joints in which the preoperative acetabular head index was less than 60% and the acetabular angle was larger than 30 degrees, the JOA score at 10 years or later was lower than that of the other joints. Based on these findings, valgus-extension osteotomy was evaluated as a useful surgical method for advanced or terminal osteoarthritis in young or middle-aged patients. Predictive factors for long-term prognosis would be the preoperative length of roof osteophyte, joint space widening, and the degree of femoral head covering.

Histological findings of bone marrow edema pattern on MRI in osteonecrosis of the femoral head

Sequential magnetic resonance imaging (MRI) was performed on a 38-year-old woman with systemic lupus erythematosus who had received corticosteroid and had developed non-traumatic osteonecrosis of the femoral head. The initial MR finding was a band lesion on the T1-weighted image, which had been present before the onset of symptoms. At the onset of symptoms, a diffuse bone marrow edema pattern, with a low signal intensity on T1 and high signal intensity on T2-weighted images, was noted around the band lesion, extending to the femoral neck. Histopathologically, this region was found to consist of serous exudate, focal interstitial hemorrhage, and mild fibrosis, without any evidence of extension of osteonecrosis. It should be noted that extension of a low signal intensity area on MRI after the onset of hip pain may not be the result of the extension of osteonecrosis, but may represent concomitant edema due to collapse.

Ceramic endoprosthesis for aggressive giant cell tumors near the knee: eight cases followed for more than 10 years

Eight patients with locally aggressive giant cell tumor were treated with marginal resection and implantation of a ceramic endoprosthesis with a non-hinged knee joint. The patients have been followed-up for between 10 to 16 years. Newly formed bone appeared at the junction between implant and cortex and in 2 cases subsidence of the implant was seen. All the patients had good function of the knee and no revision was needed.

Extra-articular wide tumor resection and limb reconstruction in malignant bone tumors invading the knee joint

We demonstrate our procedure of extra-articular wide tumor resection and its clinical outcome. The knee joint including the femorotibial, patellofemoral and the proximal tibiofibular joints was totally resected without any view of articular cartilage and synovium. The resected limb was reconstructed with endoprosthesis of the knee joint. The average score of the limb function evaluated by ISOLS criteria was 69.3% in all patients. The limb function of these patients was almost the same as that of the patients who received the intra-articular procedure. The procedure of extra-articular resection was theoretically necessary and clinically practical.

Effectiveness of activated vitamin D3 on improving prognosis of osteosarcoma patients

We examined the survival prognosis of patients with osteosarcoma after orally administering the active form of vitamin D3, 1alpha (OH) D3 (alphaD3). The 29 patients, ranging in age from 9 to 58 years (mean, 19 years), with osteosarcoma were treated in our department between 1983 and 1995. The surgical stage was IIB in all patients. Among the 29 patients, alphaD3 was administered to 18 patients, and the remaining 11 patients served as controls. These patients underwent chemotherapy mainly with adriamycin and cisplatin, and wide tumor resection. In the alphaD3-treated group, the 5- or 10-year survival rate was 61.1%, while in the untreated group, the 5-year survival rate was 63.6%, and 10-year survival rate was 33.9%. Prognosis of the patients treated with alphaD3 tended to be better than that of untreated patients, but there was no significant difference in the survival rate between the groups (p=0.3823). The survival rate in the group treated with a total dose of alphaD3 more than 1,500 microg was also higher than that in the untreated group, but the difference was not significant (p=0.0740). Therefore, we concluded that alphaD3 at the dose used in this study was not effective in improving the prognosis of osteosarcoma patients.