Objective

Recently, the short stem, taken on preservation of the femoral bone, is available on total hip arthroplasty and on femoral head prosthetic replacement. The handling of the short stem is easier than that of standard stem on implantation of femur. However, it would be difficult to make the direction of stem axis straight in femoral marrow cavity. Actually we experienced that the lateral cortical bone of the proximal femur was ground unevenly on rasping for implantation of the short stem. The aim of this study was to identify the efficacy of dulled rasp on implanting the short stem.

Background

Previously, the Coonrad-Morrey elbow system has typically been performed using linked-type total elbow arthroplasty (TEA) implants. However, this implant have been reported to be associated with some problems, such as wearing down, loosening, the complexity of the necessary surgical techniques and inappropriate implant size for Asian people.

The Discovery elbow system (Biomet Inc., Warsaw, US) has recently been developed and it has many advantages when compared to Coonrad-Morrey implant, but the treatment outcome for this system is unclear in patients with rheumatoid arthritis (RA).

Atlanto-axial subluxation (AAS) presents with marked frequency among patients with instability in rheumatoid arthritis (RA) patients. This study investigated the morphology of the atlanto-occipital joint (AOJ) in AAS patients due to RA using computed tomography, and examined the relationship between its morphology and other radiographic results

Twenty-six consecutive patients with AAS due to RA treated by surgery were reviewed. In all patients, the AOJ was morphologically evaluated using sagittal reconstruction view on computed tomography before surgery. Moreover, the ADI value was investigated at the neutral position, and atlanto-axial angle (AAA) at the neutral and maximal flexion position in preoperative lateral cradiographs. The morphology of the AOJ was classified into three types as follows: a normal type which showed a maintenance of the joint space, a narrow type which showed a disappearance of the joint space and a fused type which showed the fusion of the AOJ.

The pre-operative CT image of the AOJ demonstrated a normal type bilaterally in six cases (Group A). In 15 cases (Group B), CT image demonstrated narrowing on at least one side of the AOJ. In five cases (Group C), CT images demonstrated fusion on at least one side of the AOJ. The average ADI value at the flexion position was 10.7 mm in Group A, 11.7 mm in Group B, and 12.6 mm in Group C. There was no significant difference among those groups. The average ADI value at the neutral position before surgery was 2.8 mm in Group A, 5.9 mm in Group B, and 10.4 mm in Group C. There was no significant difference between Group A and B, and Group B and C; however, there was a significant difference between Group A and C (p < 0.004). The average AAA value was 25.3 degrees in Group A, 19.3 degrees in Group B and 3.4 degrees in Group C. There was no significant difference between Group A and B; however, there was a significant difference between Group A and C (p < 0.002), and Group B and C (p < 0.007).

This study showed that fusion or ankylosis of the AOJ induced an enlargement of the ADI and anterior inclination of the atlas in the neutral position—despite the fact that normal findings of AOJ showed a slight displacement of the atlas to axis in RA patients showing AAS involvement.

We retrospectively reviewed 71 histopathologically-confirmed bone and soft-tissue metastases of unknown origin at presentation. In order to identify the site of the primary tumour all 71 cases were examined with conventional procedures, including CT, serum tumour markers, a plain radiograph, ultrasound examination and endoscopic examinations, and 24 of the 71 cases underwent 2-deoxy-2-[F-18] fluoro-D-glucose positron emission tomography (FDG-PET). This detected multiple bone metastases in nine patients and the primary site in 12 of the 24 cases; conventional studies revealed 16 primary tumours. There was no significant difference in sensitivity between FDG-PET and conventional studies.

The mean maximal standardised uptake value of the metastatic tumours was significantly higher than that of the primary tumours, which is likely to explain why FDG-PET did not provide better results. It was not superior to conventional procedures in the search for the primary site of bone and soft-tissue metastases; however, it seemed to be useful in the staging of malignancy.

We prospectively examined the physical and imaging findings, including MRI, of 23 patients with spontaneous osteonecrosis of the knee after obtaining informed consent to acquire tissue specimens at surgery. There were four men and 19 women, with a mean age of 67.5 years (58 to 77). Plain radiographs were designated as stages 1, 2, 3 or 4 according to the classification of Koshino. Five knees were classified as stage 1, five as stage 2, seven as stage 3 and six as stage 4. The histological specimens were stained with haematoxylin and eosin and tetrachrome.

In the early stages of the condition, a subchondral fracture was noted in the absence of any features of osteonecrosis, whereas in advanced stages, osteonecrotic lesions were confined to the area distal to the site of the fracture which showed impaired healing. In such cases, formation of cartilage and fibrous tissue, occurred indicating delayed or nonunion. These findings strongly suggest that the histopathology at each stage of spontaneous osteonecrosis is characterised by different types of repair reaction for subchondral fractures.

Human bone-marrow mesenchymal stem cells have an important role in the repair of musculoskeletal tissues by migrating from the bone marrow into the injured site and undergoing differentiation. We investigated the use of autologous human serum as a substitute for fetal bovine serum in the ex vivo expansion medium to avoid the transmission of dangerous transfectants during clinical reconstruction procedures.

Autologous human serum was as effective in stimulating growth of bone-marrow stem cells as fetal bovine serum. Furthermore, medium supplemented with autologous human serum was more effective in promoting motility than medium with fetal bovine serum in all cases. Addition of B-fibroblast growth factor to medium with human serum stimulated growth, but not motility. Our results suggest that autologous human serum may provide sufficient ex vivo expansion of human bone-marrow mesenchymal stem cells possessing multidifferentiation potential and may be better than fetal bovine serum in preserving high motility.

We have compared the concentrations of stromal-cell-derived factor-1 (SDF-1), matrix metalloproteinase-1 (MMP-1), MMP-9 and MMP-13 in serum before and after synovectomy or total knee replacement (TKR). We confirmed the presence of SDF-1 and its receptor CXCR4 in the synovium and articular cartilage by immunohistochemistry. We established chondrocytes by using mutant CXCR4 to block the release of MMPs.

The level of SDF-1 was decreased 5.1- and 6.7-fold in the serum of patients with OA and RA respectively, after synovectomy compared with that before surgery. MMP-9 and MMP-13 were decreased in patients with OA and RA after synovectomy. We detected SDF-1 in the synovium and the bone marrow but not in cartilage. CXCR4 was detected in articular cartilage. SDF-1 increased the release of MMP-9 and MMP-13 from chondrocytes in a dose-dependent manner. The mutant CXCR4 blocked the release of MMP-9 and MMP-13 from chondrocytes by retrovirus vector.

Synovectomy is effective in patients with OA or RA because SDF-1, which can regulate the release of MMP-9 and MMP-13 from articular chondrocytes for breakdown of cartilage, is removed by the operation.

Between 1978 and 1999, surgical treatment for talocalcaneal coalitions which failed to respond to any conservative treatment was performed. Materials consisted of 46 patients (50 feet), including 26 males (29 feet) and 20 females (21 feet). The patients’ age at the time of operation ranged from 8 to 66 years (average, 22.5 years). Major symptoms included local pain (43 feet), tumor (19 feet), numbness of the plantar side (17 feet), peroneal muscle spasm (13 feet), and varus instability of the ankle (3 feet). Major signs included limited motion of the subtalar joint (50 feet), palpation of tumor (34 feet), sensory disturbance of the plantar side (14 feet), peroneal spastic flat foot (3 feet), and limited dorsiflexion of the ankle due to contracture of the gastrocnemius muscle (2 feet). The regions of the coalitions included middle type (36 feet), posterior type (9 feet), and diffuse type (3 feet). The coalitions were all incomplete unions, that is to say fibrous or cartilaginous unions.

Surgical treatments were as follows: coalitions were excised and subtalar joints were mobilized in 31, resections alone were carried out on 16, and 3 feet underwent arthrodesis of the subtalar joint. Results of surgical treatments were evaluated using our own clinical scoring system. 28 feet were excellent, 13 were good, 8 were fair, and one foot was poor.

In principle, the purpose of surgical treatment of these coalitions involved excising the tumor to release the plantar nerve from compression and resection the coalition to gain physiological subtalar motion. However, patients experiencing osteoarthrotic changes and whose coalitions occupy most of the subtalar joint should undergo an arthrodesis of the subtalar joint.

Purpose: In recent years, many reports have described spontaneous resorption of lumbar disc herniation evaluated with Gd-enhanced MRI. We also found retrospectively that sequestrated lumbar disc herniation with Gd-enhanced MRI would disappear, and that patient with this type of lumbar disc herniation would improve clinically. But there is a question that Gd-enhanced MRI is really needed to speculate the prognosis of sequestrated lumbar disc herniation. The purpose of this study is to clarify the prognostic value of Gd-enhanced MRI for sequestrated lumber disc herniation.

Materials and methods: Since Nov. 1995, 22 patients of sequestrated lumber disc herniation were treated non-operatively under the speculation of getting good clinical result prospectively. From Nov. 1995 to Oct. 1997, 9 patients with sequestrated lumbar disc herniation with ring-enhancement on Gd-enhanced MRI were treated non-operatively (Group A). From Nov. 1997 to July 2000, 13 patients with sequestrated lumbar disc herniation were treated non-operatively without Gd-enhanced MRI examination (Group B). Clinical results and the last MRI findings of Group A were compared with that of Group B.

Results: In Group A, all cases were treated non-operatively and all of them improved clinically within a month of the first MRI examinations. Mean period of NSAID administration was 37 days (range 14–67 days), and the last MRI examinations revealed that the herniated masses disappeared in 5 cases and that the size of herniations diminished in 4 cases. All of 9 cases obtained good clinical results. In Group B, all cases were treated non-operatively but one, whose clinical symptoms were not improved within a month of the first MRI examination. Mean period of NSAID administration was 38 days (range 7–110 days), and the last MRI examinations revealed that the herniated masses disappeared in 5 cases and that the size of herniations diminished in 5 cases. Remaining 2 cases, the second MRI was not examined for some reasons. All of 12 cases obtained good clinical results. There were no differences between Group A and Group B by means of clinical results.

Conclusions: Gd-enhanced MRI is not needed to speculate the prognosis of sequestrated lumbar disc herniation. In the case of sequestrated lumbar disc herniation, good clinical result could be obtained without Gd-enhanced MRI examination at the first MRI examination.

We have analysed retrospectively the relationship between the axial parameters of alignment of the lower limb and the recurrence of varus deformity after high tibial osteotomy. We studied 29 patients (37 knees) with a mean age at surgery of 66 years. The mean follow-up was for 7.4 years (5 to 10.5). Recurrence of varus deformity was defined as an increase in the femorotibial angle of 3° or more, compared with that obtained six months after the operation. There were four patients (four knees) with recurrence of varus deformity. They had a greater varus inclination of the distal femur than those without varus recurrence.

An association between varus inclination of the distal femur and horizontal obliquity of the joint surface was observed. Excessive obliquity prevents the shift of weight-bearing to the lateral compartment, and may cause a recurrence of varus deformity after high tibial osteotomy.

We performed positron emission tomography (PET) with ¹⁸fluorine-fluoro-2-deoxy-D-glucose (FDG) on 55 patients with tumours involving the musculoskeletal system in order to evaluate its role in operative planning. The standardised uptake value (SUV) of FDG was calculated and, to distinguish malignancies from benign lesions, the cases were divided into high (≥ 1.9) and low (< 1.9) SUV groups.

The sensitivity of PET for correctly diagnosing malignancy was 100% with a specificity of 76.9% and an overall accuracy of 83.0%. The mean SUV for metastatic lesions was twice that for primary sarcomas (p < 0.0015).

Our results suggest that the SUV may be useful in differentiating malignant tumours from benign lesions. However, some of the latter, such as schwannomas, had high SUVs so that biopsy or wide resection was selected as the first operation. Thus, some other quantitative analysis may be required for preoperative planning in cases of high-SUV neurogenic benign tumours. The reverse transcription-polymerase chain reaction revealed that the RNA message of a key enzyme in glucose metabolism, phosphohexose isomerase (PHI)/autocrine motility factor, was augmented in only high FDG-uptake lesions, suggesting that a high expression of the PHI message may be associated with accumulation of FDG in musculoskeletal tumours.

We studied 37 patients with varus osteoarthritis of the knee to determine the influence of the bone mineral density (BMD) on the varus deformity. There were 15 men (21 knees) and 22 women (38 knees). The mean age of the men was 69 years and of the women 68 years. BMD was measured in the L1–L4 spinal region using dual X-ray absorptiometry.

In the women a low level of BMD was associated with varus deformity originating at the proximal tibia, but a high level was predominantly linked with deformity originating in the joint space. Similar findings were obtained in the men.

Our results suggest that a low BMD predisposes to trabecular microfractures and consequently increased stress on the articular cartilage. A low BMD does not preclude osteoarthritic change in the knee.

We report six patients with isolated paralysis of the infraspinatus and discuss the diagnosis, pathology, treatment, and outcome over a mean follow-up period of 33 months. Four patients were shown to have space-occupying lesions at the spinoglenoid notch by MRI or ultrasonography or both, and ganglia were confirmed and removed surgically in three, with good results. Ganglia at this site are not uncommon and should be included in the differential diagnosis of patients presenting with shoulder pain and weakness.