Introduction

Total knee arthroplasty (TKA) is one of the most successful surgeries to relieve pain and dysfunction caused by severe arthritis. However, it is a still big problem that there is a possibility of death in pulmonary embolism (PE) after TKA. We previously reported that there was more incidence of asymptomatic PE than estimated in general by detail examinations. But it was difficult to whom we decided to perform additional examinations except the patients with some doubtful symptoms. Therefore, we investigated detail of PE patients after primary TKA to find out anything key point in PE.

Introduction

The treatment of osteonecrosis of the femoral head (ONFH) in young and active patients remains a challenge. The purpose of this study was to determine and compare the clinical and radiographic results of the two different hip resurfacing systems; hemi-resurfacing and metal-on-metal total hip resurfacing in patients with ONFH.

Introduction

Hip resurfacing has become a popular procedure for young active patients with osteonecrosis of the femoral head. However, it is not yet clear exactly how much osteonecrosis would permit this procedure and how much would be a contraindication. The aim of the present study was to analyze the resurfaced femoral head using finite element models and, in particular, to examine the influence of the extent of osteonecrosis and metaphysical stem shaft angles within the femoral head.

The position of the acetabular component affects the result of total hip arthroplasty(THA) in terms of postoperative dislocation, impingement, wear etc.

However, as it is much difficult to place the component in the appropriate position for the cases of severe acetabular deformity, we used a Computed tomography(CT)-based navigation for THA in such cases. Therefore, the purpose of this study was to estimate the accuracy of a CT-based navigation in terms of acetabular component positioning in THA for severe acetabular deformities.

13 patients (1 man, 12 women), 14 hips underwent THA using a posterolateral approach with a CT-based navigation. The diagnoses were severe developmental dysplasia (Crowe group III, IV) in 6, ankylosis in 3, destructive arthritis after infection in 2, Charcot joint, and arthrodesed hip. And, we evaluated the differences of component position from the center of the anterior pelvic plane(APP), anteversion angle, and inclination angle relative to APP between the intraoperative data from the navigation system and the data from postoperative CT. Considering the intra-observer error, the measurement was done three times respectively and the mean value was accepted. We also estimated the difference between the component size planned and that implanted.

The mean difference between intraoperative records and actual postoperative results of the component position shows 3.3 mm(range: 0–7.0, SD: 2.2) for the horizontal position, 3.2 mm(range: 0–9.7, SD: 4.5) for the vertical position, 4.4 mm(range: 2.0–7.7, SD: 1.6) for the antero-posterior position from the center of the APP, 1.3 degrees(range: 0–3.0, SD: 0.9) for the inclination and 2.9 degrees(range: 0.3–8.3, SD: 2.2) for the anteversion respectively. All components were placed in the safe zone by Lewinnek. The component size was predicted in 10/14(71.4%) hips. There were no complications related to the use of the navigation.

This study showed the accuracy of cup positioning using a CT-based navigation in THA for the cases of severe acetabular deformity. We concluded that this system was a useful tool for surgeon to identify orientation, implant acetabular component at the precise position and angle, and to reduce the incidence of some complications especially for patients with these severe acetabular deformities.

Objective: The treatment of osteonecrosis of the femoral head (ONFH) in young active patients remains a challenge. The purpose of this study was to determine and compare the clinical and radiographic results of the two different hip resurfacing systems, hemi-resurfacing and metal-on-metal total-resurfacing, in patients with ONFH.

Materials and Methods: We retrospectively reviewed 20 patients with 30 hips with ONFH who underwent hemi-resurfacing or total-resurfacing between November 2002 and February 2006. We mainly performed hemi-resurfacing for early stage ONFH, and total-resurfacing for advanced stage. Fifteen hips in 11 patients had a hemi-resurfacing component (Conserve, Wright Medical Co) with the mean age at operation of 50 years and the average follow-up of 5.5 years. Fifteen hips in 10 patients had a metal-on-metal total-resurfacing component (Birmingham hip resurfacing, Smith & Nephew Co.) with the mean age at operation of 40 years and the average follow-up of 5 years. Clinical and radiographic reviews were performed.

Results: The average postoperative JOA hip scores were 86 points in hemi-resurfacing, 96 points in total-resurfacing. The difference of pain score was a main factor to explain the difference of total JOA hip score in the two groups. Both implants were radiographically stable, but radiolucent lines around the metaphyseal stem were more frequent in total-resurfacing. In hemi-resurfacing patients, ten of 15 hips had groin pain or groin discomfort, three hips were revised to total hip arthroplasties (THA) because of femoral neck fracture, acetabular pro-trusio, and osteoarthritic change, respectively. On the other hand, in total-resurfacing patients, there were no revision and no groin pain.

Discussion: In the prosthetic treatment of young active patients with ONFH, it is theoretically desirable to choose an implant with conservative design in anticipation of the future revision surgery. Hemi-resurfacing hip arthroplasty is the most conservative implant for the treatment of ONFH. However, the results of hemi-resurfacing in this study have been very disappointing due to high revision rates and insufficient pain relief despite of the good implant stability. On the other hand, the pain relief and implant survivorship after total-resurfacing were superior to the results of hemi-resurfacing, although the usages of the total-resurfacing were for more advanced cases. These results suggested that total-resurfacing was a more valuable treatment option for active patients with ONFH than hemi-resurfacing

Introduction An international six-centre prospective observational cohort study.

Objective. To assess the feasibility of radical surgical excisional treatment of spinal metastasis

Materials and methods. Patients with histologically confirmed spinal metastasis originating from epithelial primary site mostly treated with instrumented surgery were studied. Surgical strategies were either radical excisional (enbloc and debulking) or palliative decompressive surgery. Outcomes assessed were measures of quality of life including pain, mobility, sphincter and neurological functions.

Results. A total of 223 patients with a mean age of 61 years and equal number of males and females were studied. Breast, renal, lung and prostate accounted for three quarters of tumours and 60% had metastasis that extended beyond one vertebra. Most patients presented with pain (92%), paraparesis (24%) and abnormal urinary sphincter 22% (5% were incontinent). Seventy four percent of patients underwent radical surgery, 92% of all patients had instrumented fixation. 73% of the radical group had improved pain control (63% for palliative group), 72% regained ability to walk (45% for palliative group), 92% maintained a functional neurological function of Frankel E/D (64% for palliative) and 55% had improved sphincter control (21% for palliative group).

Overall of all petients who underwent surgery, 71% had improved pain control, 53% regained mobility, 64% improved by at least one Frankel grade or maintained normal neurology and 39% regained normal urinary sphincter function. While 18% were bed bound preoperatively, only 5% were still in bed postoperatively. Perioperative mortality rate was 5.8% and morbidity was 21%. The median survival for the cohort was 352 days (11.7 months). The radical surgery group had a median survival of 438 days and the palliative group 112 days (P = 0.003).

Conclusion. Surgical treatment of spinal metastatic tumour is feasible with low mortality, an acceptably low morbidity and affords patients better quality of remaining life. Radical surgical excision has better outcome than palliative surgery in pain control and in neurological function rescue including regaining mobility and improvement in sphincter control.

Introduction: The purpose of this study was to evaluate the clinical results of Sugioka’s transtrochanteric rotational osteotomy (TRO) for osteonecrosis of the femoral head.

Materials and Methods: We reviewed 54 hips in 49 patients who underwent TRO between 1986 and 1998 (follow-up rate was 90%). The mean age of patients was thirty-six years. The average duration of follow-up was 116 months (range, 60 to 201 months). Risk factors for osteonecrosis was steroids in 23 patients, idiopathic in 15 patients, alcohol in 13 patients, and others in three patients. Using the staging system of The Japanese Investigation Committee of the Ministry of Health and Welfare, 16 hips were in Stage 2, 23 hips in Stage 3A, 13 hips in Stage 3B, and two hips in Stage 4. Clinical assessments were made according to the Japanese Orthopaedics Association hip scoring system (JOA score).

Results: The overall results were excellent (JOA score of 90 to 100 points) in 22 hips (40.7%), good (80 to 89 points) in 16 hips (29.6%), fair (65 to 79 points) in 3 hips (5.5%), and poor (fewer than 64 points) in 13 hips (24.1%). The result was influenced by post-operative complications, the ratio of transposed intact femoral articular surface to the acetabular weight-bearing area after TRO, and the pre-operative stage. All hips with a ratio less than 40% showed progressive collapse. All Stage 2 hips with the ratio more than 40% showed excellent or good results. Conversely, 19% and 25% of the hips were fair or poor in Stage 3A and 3B hips even though the ratio was more than 40%. All Stage 4 hips had poor results.

Discussion: We conclude that satisfactory results can be achieved using TRO by maintaining exact surgical technique and by limiting the surgical indications. The hips in early or intermediate stages with sufficient intact area are good candidates for TRO.

Introduction: In general a loose-balanced total knee arthroplasty (TKA) are believed to gain good postoperative range of motion (ROM), however, too much laxity is thought to be a cause for persistent pain and catastrophic long-term results.

Materials and methods: We measured the antero-posterior and medio-lateral laxity to evaluate the influence of stability after cruciate-retaining TKA on ROM, pain score in Knee Society score and Functional score at 4–7 years after the operation. Twenty-one knees in 15 patients with an average age of 68 years (range, 58–78) who had a PCL retaining TKA for osteoarthrosis were examined (YS-4, 16 knees; AGC-S, 5 knees). There were 12 women and 3 men. Anteroposterior laxity was examined using a KT 2000 arthrometer at 30-degree knee flexion. Mediolateral laxity was examined at full extension with manual stress x-rays.

Results: Average ROM was 112 degrees (range, 90–140 degrees), antero-posterior laxity was 9.7 mm (range, 2–27 mm) and mediolateral laxity was 10.6 degrees (range, 5–22 degrees). Knee Society pain score was 47 (range, 10–50) and Functional score was 82 (range, 40–100). No significant difference in ROM and clinical scores were noted between the lax and the stable knees. Correlations between ROM and anteroposterior or medio-lateral laxity were not significant (P = 0.55, P = 0.05, respectively; Spearman’s correlation efficient).

Discussion and conclusion: A loose-balanced TKA did not gain good post-operative ROM. No parameters suggested that lax knees got better flexion angle, worse pain score and functional score than stable knees.

Although bone loss and ligamentous instability are usually indications for the use of constraining prostheses in revision total knee arthroplasty (TKA), several reports have documented a high rate of failure with these prostheses. We therefore tried using the cruciate retaining augmentable type prosthesis (NexGen CRA) if a good intraoperative ligamentous balance could be obtained with revision TKA.

CRA was used on nine knees of seven patients with an average age of 71.7 years. The follow-up lasted for an average of 1.6 years. Clinical evaluation consisted of instability ratings, knee score, range of motion and %MA (mechanical axis) as an index of the alignment. These patients showed improvement varus instability from a mean of 7.0° preoperatively to a mean of 1.5° postoperatively, and in valgus instability from 5.3° to 1.3°.

The knee score was significantly improved from 41 to 81, but the %MA resulted in an unsatisfactory improvement from −8.8% to 34.0%. The femoral anatomical-mechanical angle (FAMA) was measured as a parameter of bowing deformity of the femur, and the knees were divided into two groups, the bowing group consisting of the knees with an FMA of more than 8° (n=6, average 9.0°), the normal group of knees with an FAMA of less than 7° in FAMA (n=3, average 6.7°). The postoperative %MA showed a mean value of 40.9% for the normal group, and 30.6% in the bowing group. These results demonstrated that the discrepancy between FAMA for the bowing group(=9.0°) and the valgus angle of the stem of the femoral component (6.0°) was the cause of the malalignment in the bowing group. These clinical results suggest that the cruciate retaining augmentable type prosthesis can be used successfully for selected revision cases, but that malalignment in knees with bowed femora may remain a problem.