Relief from pain after Bombelli's valgus-extension osteotomy, and effectiveness of the combined shelf operation.

Between 1979 and 1993, we treated 67 hips in 58 patients with severe osteoarthritis caused by congenital dislocation of the hip, employing Bombelli's valgus-extension osteotomy. The mean age of the patients was 43.6 years (range, 23-59 years). The mean follow-up period was 9.7 years (range, 5-16 years). Thirty-three of the 67 joints were followed-up for more than 10 years after the operation. Of the 67 joints, 31 were operated on by Bombelli's valgus-extension osteotomy combined with a shelf operation (combined group), and 36 by Bombelli's valgus-extension osteotomy alone (single group). Clinical evaluation was made according to the Japanese Orthopaedic Association (JOA) hip score system (JOA hip score). In order to assess the effectiveness of this operation in regard to sustained relief from pain after the operation, Kaplan-Meier survivor analysis was performed on the basis of pain score on the JOA hip score. The end-point of the Kaplan-Meier analysis was defined as a score of less than 20 points on the pain score at the time of follow-up or conversion to total hip arthroplasty. In order to analyze the factors that exacerbated pain and to assess the effectiveness of the combined shelf operation, the degree of superior displacement of the femoral head (measured from roentgenograms) after the operation was examined in relation to the pain score. The mean JOA hip score improved, from 56.1+/-11.0 before the operation to 77.0+/-16.1 at the latest follow-up. Kaplan-Meier analysis showed a survival rate of 79.4% 10 years after the operation. Superior displacement of the femoral head had gradually progressed with time after the operation in patients with and without the combined shelf operation. Displacement of the femoral head was positively correlated with the acetabular angle of the weight-bearing surface (WBS angle) (sourcil) preoperation. The mean pain score in the combined group was significantly higher than that in the single group 6 to 9 years after the operation. The results of our assessments led us to conclude that Bombelli's valgus-extention osteotomy is satisfactory as far as clinical and radiological evaluations are concerned, as relief from the pain has continued for more than 10 years after the operation. The combined shelf operation is effective for relieving pain in severe osteoarthritis caused by congenital dislocation of the hip.

Epidemiology of cervical and trochanteric fractures of the proximal femur in 1994 in Tangshan, China.

The purpose of this study was to determine the incidence of cervical and trochanteric fractures of the proximal femur in 1994 in Tangshan City, China. There are many reports on hip fracture incidence in many countries, suggesting that there are many factors affecting hip fractures. We visited 15 hospitals with an orthopaedic department within Tangshan City, and reviewed the medical records and radiographs of all patients with hip fractures occurring between January 1 and December 31, 1994. The population of Tangshan in 1994 was determined to be 1,454,543 (746,015 males and 708,528 females). The population of those over 65 years of age was 88,490 (41,519 males and 46,971 females), representing 6.08% of the total population. This study detected 184 cervical and trochanteric fractures of the proximal femur in 1994 in Tangshan (127 men and 57 women). The overall incidence or rate of the combined number of cervical and trochanteric fractures was 25 fractures per 100,000 population per year for men and 12 for women. There were a total of 147 cervical fractures (80%) and 37 trochanteric fractures (20%). The incidence of the combined number of cervical and trochanteric fractures in patients over 70 years of age increased to 108 for men and 156 for women. The incidence of hip fractures increased with age in both sex groups, especially in women over 65. Severe trauma fractures happened more often in younger groups, and mainly occurred in men, which may be a result of the particular composition of the population in Tangshan, which is young and male dominated. In addition, because Tangshan is an industrial city, many of its citizens are involved in occupations requiring a high level of physical activity.

Arthrodesis of the hip joint using an external fixator.

Arthrodesis of the hip has been plagued by high rates of nonunion, and by complications associated with prolonged cast immobilization. To prevent these problems, we devised a procedure for hip arthrodesis using an external fixator in combination with internal fixation at the fusion site. We have treated nine patients with this technique. All of the arthrodeses were solidly united without wound infections at the most recent follow-up. Patients were able to leave their hospital bed and walk on the affected limb with a cane shortly after surgery. This was possible because the external fixator was low in profile, as it was applied from the anterosuperior iliac spine to the femoral shaft, and provided rigid stabilization of the arthrodesis. The technique resulted in a reduction in the period of bed rest, immediate postoperative mobilization, shorter periods of hospitalization, no limitation in the range of knee and ankle motion, improvement in the patient's ability to carry out the personal hygiene, and fewer complications.

Increase in the incidence of cervical and trochanteric fractures of the proximal femur in Niigata Prefecture, Japan.

This study aimed to determine the incidence of cervical and trochanteric fractures of the proximal femur in 1994 in Niigata Prefecture, Japan, and to compare this incidence with those previously reported in Niigata in 1985, 1987, and 1989. We visited all hospitals within Niigata Prefecture having an orthopedic department and reviewed the medical records and radiographs of all patients who sustained such fractures in 1994. The population of Niigata Prefecture was determined in 1994 to be 2,483,879 (1,205,151 males and 1,278,728 females). The population over 65 years of age was 428,795 (172,788 males and 256,007 females), representing 17.3% of the total population. In 1994, there were 1,468 cervical or trochanteric fractures in 378 males and 1,090 females, with a male-to-female ratio of 1:2.9. The incidence of these fractures in persons over 65 years of age was 304 fractures per 100,000 population per year. Of 528 cervical and 940 trochanteric fractures, the latter accounted for 64% of the total number. The age-specific incidence of the fractures in Niigata exhibited an exponential increase with age, similar to those reported in Sweden and the United States. However, the incidence was lower than in those countries. When comparing the number of cervical and trochanteric fractures in 1994 with the numbers reported in 1985, 1987, and 1989, it is evident that the overall number and incidence of these fractures has been increasing over this period. Even if the difference of the age-specific population among these years is adjusted, the fractures have been increasing.

Enhancing screw stability in osteosynthesis with hydroxyapatite granules.

We employed hydroxyapatite (HA) granules to enhance screw fixation in revision surgery of failed osteosynthesis with a compression hip screw system in an 83-year-old woman. After reduction of the fracture, the fracture site with a large bone defect was filled with HA granules, and osteosynthesis was accomplished with a double cannulated lag screw and plate system. We feel that this HA granule augmentation method may also be suitable for osteosynthesis in other osteoporotic fractures.

Vascularized iliac bone graft for avascular necrosis of the femoral head.

This is a followup study of 31 hips in 24 patients from 2 to 11 years after receiving a vascularized iliac bone graft for nontraumatic avascular necrosis of the femoral head. The clinical results according to the Merle d'Aubigne score were satisfactory in 24 (77%) of the hips, whereas the radiographic success rate for all hips was 58%. The extent of the lesion as shown on anteroposterior radiographs was predictive of the eventual outcome. Seven (39%) of 18 hips with a lateral type lesion had satisfactory results, whereas 11 (85%) of 13 hips with a medial type lesion had satisfactory results. All of the hips with a medial type lesion and a lateral head index of greater than 12% had satisfactory results. For the success of this procedure, the lateral buttress of the normal portion in the femoral head was necessary.

Bone particles disturb new bone formation on the interface of the titanium implant after reaming of the marrow cavity.

Histomorphometric studies were conducted in rats to determine whether bone particles would disturb new bone formation on the interface of titanium implants inserted after reaming of the marrow cavity. In eighty 10-week-old female Wistar rats, smooth-surfaced titanium alloy implants were inserted bilaterally into the marrow cavity after reaming in the distal femur. There were three experimental groups: in the irrigated femora, sterile saline was flushed through the medullary canal; in the particle femora, autologous bone particles were inserted into the intramedullary cavity; and in the reamed femora, the implant was inserted without procedures after reaming. The rats were sacrificed at one, two, four or eight weeks postoperatively, and Villanueva bone staining was applied for histomorphometric studies. The bone volume of new bone on the interface of the implant in the irrigated femora was greater than that in the particle or the reamed femora throughout the study period. The results suggest that clearance of bone particles by irrigation after reaming of the marrow cavity significantly facilitates new bone formation on the interface of implants by one week. The findings also suggest the potential clinical application of total canal irrigation prior to insertion of cementless femoral components as well as cemented prosthesis.

Reduction in cement-bone interface shear strength between primary and revision arthroplasty.

This study quantified changes in the cement-bone interface shear strength between primary and first- and second-revision arthroplasties as a function of mechanical interlock between the cement and bone. There were 128 segments obtained from four pairs of fresh human femora that were prepared sequentially as for primary and first and second revisions, taking care to maintain original canal morphology. Cement was pressurized into the cavity of the anatomic specimens, and the maximum interface shear strength between the cement plug and the bone was experimentally determined for each revision. First-revision interface shear strength was reduced to 20.6% of primary strength, and second revision strength to 6.8% of primary strength.