Aims

The aim of this study was to evaluate the time course of changes in parameters of diffusion tensor imaging (DTI) such as fractional anisotropy (FA) and apparent diffusion coefficient (ADC) in patients with symptomatic lumbar disc herniation. We also investigated the correlation between the severity of neurological symptoms and these parameters.

We compared the results ten years after an inverted V-shaped high tibial osteotomy with those of a historical series of conventional closing-wedge osteotomies. The closing-wedge series consisted of 56 knees in 51 patients with a mean follow-up of 11 years (10 to 15). The inverted V-shaped osteotomy was evaluated in 48 knees in 43 patients at a mean follow-up of 14 years (10 to 19). All the patients were scored using the Japanese Orthopaedic Association rating scale for osteoarthritis of the knee and radiological assessment.

The pre-operative grade of osteoarthritis was similar in both groups. Post-operatively, the knee function score was graded as satisfactory in 63% (35) of the closing-wedge group but in 89% (43) of the inverted V-shaped osteotomy group. Post-operative radiological examination showed that delayed union and loss of correction occurred more often after a closing-wedge osteotomy than after an inverted V-shaped procedure.

Our study suggests that the inverted V-shaped osteotomy may offer more dependable long-term results than traditional closing-wedge osteotomy.

Total knee arthroplasty (TKA) after proximal tibial valgus osteotomy is thought to be technical demanded and its outcome is not as sufficient as primary TKA. Purpose of this study is to identify particular surgical procedures and outcome of TKA after proximal tibial valgus osteotomy in the different type of osteotomies. Fourteen TKA after proximal tibial valgus osteotomies were underwent for 13 patients with osteoarthritis. Average age at surgery was 72 years old. The mean duration from proximal tibial valgus ostetomy to TKA was 9 years and 10 months and the mean follow up period after TKA was three years and nine months. Four closed wedged osteotomies, five modified Levy’s reversed V shaped osteotomies and five domed osteotomies were underwent before TKA. The V-Y lengthening of quadriceps tendon or osteotomy of the tibial tubercle was necessary for each one knee. Both knee had patella infera due to previous osteotomies of tibial tubercle for patello- femoral osteoarthritis. 11 lateral releases including release of lateral collateral ligament and two lengthening of iliotbial tract were needed to achieve sufficient ligament balance. The stems of tibial components could be placed almost centrally especially in knees, which had reversed V shaped oseteotomies and laterally in knees, which had domed or closed wedged osteotomies. Clinical results evaluated by Japan Orthopedic Association score had improved from 53 points before TKA to 84 points after TKA. This study suggests that 1) approach is difficult in the knee, which had previous osteotomy of tibial tubercle, 2) lateral release including lateral collateral ligament and iliotibial tract is necessary to achieve sufficient ligament balance, 3) the stem of tibial component might be placed laterally in knees, which had previous domed oseteotomy or closed wedged osteotomy, 4) outcome of TKA after proximal valgus osteotomy is as good as primary TKA.

The aim of the study was to compare clinical results after cruciate-retaining total knee arthroplasty (TKA) between the ceramic and the Co-Cr alloy condylar prostheses.

In a prospective semi-randomised study, 218 patients underwent cruciate-retaining TKA with the Co-Cr alloy prosthesis (Kinemax®, Howmedica) or the LFA-I® prosthesis (Kyocera) composed of an alumina ceramic femoral component and a titaniumalloy tibial component with a UHMWPE insert. In each surgery, both components were fixed with PMMA cement. All the patients underwent the same postoperative management. Finally, 110 knees with the ceramic prosthesis and 84 knees with the Co-Cr prosthesis were followed up for 24 to 124 months (the average of 56 months).

Two revisions were performed in each group (tibial tray breakage and infection in the ceramic group, and loosening and infection in the Co-Cr group). In the remaining patients, there were no significant differences in the HSS knee score (85 and 86 points, respectively) and the ROM (112 and 113 degrees) between the two groups. In radiological evaluation, a radiolucent line was more frequently observed with the significance (p< 0.05) in the Co-Cr alloy group (9.5 %) than in the ceramic group (2.7 %).

In the mid-term follow-up evaluations, the clinical results of the ceramic TKA are equivalent to those of the Co-Cr alloy TKA. In addition, the ceramic prosthesis showed some statistical tendency of superiority to the Co-Cr prosthesis concerning the radiolucent line. These results encouraged us to conduct a long-term follow-up study on the ceramic total knee prosthesis.

We followed, prospectively, 77 patients (90 hips) with early-stage, non-traumatic osteonecrosis of the femoral head for a mean period of nine years. At the time of final review, 56 (62%) were symptomatic. Using the Cox model, the initial radiological stage, the progression of staging, the reduction in size of the lesions and the percentage of necrotic volume on MRI were identified as risk factors.

Using the Harris score of < 70 or surgery as the endpoint, the cumulative rates of survival were 60.0% at one year, 43.3% at two years, 38.9% at five years and 37.2% at ten years. Survival curves demonstrated that clinical deterioration could occur 90 months after the initial diagnosis, suggesting that asymptomatic patients should be followed carefully for several years. Radiological time-dependent reduction in size without progressive collapse may represent repair even when the collapse is minimal.

Since 1982, 21 patients were operated at our hospital including 12 males and 9 females. The average age were 59.4 years, the average duration of HD was 15.5 years, and DSA was in the cervical spine in 14 cases, and the lumbar spine in 7. Symptoms were pain in 21 patients (100%) and neurological deficits in 19 (90%). Histological examination of respected specimen revealed amyloid deposits in all cases.

We classified the X-rays changes from DSA in stage 0 (no change) to stage 3 (end stage), and as type A (kyphosics), B (subluxation), C (amyloid deposits in soft tissues), and D (spontaneous fusion).

All 21 cases were classified as stage 3. The 14 cervical spine cases belonged to type A or B, but all 7 lumbar spine cases belonged to type C or were combined types.

In the 14 cervical spine cases, spinal fusion was done to stabilize the spine (AO plate in 3, Axis plate in 2, Olerud system in 2, and others in 7).

In contrast, posterior decompression (laminoplasty with or without spinal fusion) was done in all 7 lumbar spine cases.

The results were evaluated from the JOA scores. The score improved from 6.1 to 10.1 points (full score:17) in cervical patients and it improved from 12.2 to 20.2 points (full score:29) in lumbar patients. One patient died 2 days after surgery because of massive blood loss.

Twenty-one operations for DSA were investigated. Surgical strategies were decompression, stabilization, or combination. In addition, minimum invasive procedure should be considered for the patients with high-risk and the poor bone quality.