Long-term follow-up of metal-on-metal total hip replacement.

Metal-on-metal articulations were reintroduced to reduce polyethylene particle-induced osteolysis. Elevated serum metal levels have been detected at short- and intermediate-term follow-up. There is little knowledge about long-term effects of increased ionic metal generation. Our study was undertaken to provide information about long-term survival, clinical outcome, radiographic appearance, and serum metal concentrations after a minimum 10 years follow-up with a metal-on-metal hip prosthesis: 105 cementless primary total hip prostheses with metal-on-metal articulating surfaces were implanted in 98 patients with a mean age of 56 years. Clinical data, radiographs, and blood samples were obtained at a follow-up visit 10 years after implantation. Serum cobalt and chromium levels were determined with use of atomic absorption spectrometry. General laboratory analyses included a full blood count and kidney function parameters. The Harris score was 92 points and the UCLA score 6 points after 10 years. Small osteolytic lesions and radiolucent lines were found in Gruen's zones 1, 7, 8, and 14. The probability of survival was 98.6%. The median serum cobalt concentration of the 22 patients with their hip replacement as the only source of cobalt was 0.75 microg/L (range, 0.3-50.1 microg/L). No patient was diagnosed with renal insufficiency during the study period. Five patients were diagnosed with a malignancy between surgery and the follow-up. We do not have evidence of an increased rate of primary malignancies nor could we detect renal failure in our study group. Serum metal levels did not differ from short- and intermediate term follow-up values.

Cementless total hip arthroplasty with the rectangular titanium Zweymuller stem. A concise follow-up, at a minimum of fifteen years, of a previous report.

Between October 1986 and November 1987, 208 total hip arthroplasties were performed with use of the cementless Zweymüller stem and a threaded cup in 200 consecutive patients. Of 102 patients (108 hips) who were available for follow-up at a minimum of 180 months postoperatively, eighty-three (eighty-nine hips) had the primary joint replacement still intact. No stem had been revised because of aseptic loosening, but we found various degrees of osteolysis around sixteen (18%) of the implants. The probability of survival of the stem at fifteen years was 0.98 (95% confidence interval, 0.96 to 1.00). The probability of survival of the cup was 0.85 (95% confidence interval, 0.79 to 0.91).

Prevalence of aneurysmal and solitary bone cysts in young patients.

Aneurysmal and solitary bone cysts develop most commonly during skeletal growth. The objective of our epidemiologic study was to evaluate the prevalence, recurrence rate, and probability of recurrence-free survival for aneurysmal and solitary bone cysts in young patients. We did a population-based analysis of 141 histologically confirmed cases. Seventy-three patients with aneurysmal bone cysts and 68 patients with solitary bone cysts were registered. The annual prevalence was 0.32 per 100,000 individuals (range, 0-1.238) for aneurysmal cysts, with a 1.8:1 male to female ratio and a median age of the patients of 11.1 years (range, 1-19.7 years). For solitary bone cysts, the calculated annual prevalence was 0.30 (range, 0-0.963) with a median age of the patients of 1.1 years (range, 0.5-19.9) and a 1.96:1 male to female ratio. Recurrent lesions occurred frequently in young males. Secondary aneurysmal bone cysts were observed only in females. During skeletal growth, aneurysmal and juvenile bone cysts more often occur in males with a peak prevalence at approximately 11 years of age. A greater prevalence of aneurysmal bone cysts in young individuals is associated with skeletal growth and immaturity. Young age and male gender are associated with an increased risk of local recurrence.

Endothelial precursor cells in the synovial tissue of patients with rheumatoid arthritis and osteoarthritis.

OBJECTIVE: To find evidence for the presence of endothelial precursor cells, which can induce new vessel formation, in the synovial tissue of patients with rheumatoid arthritis (RA) and osteoarthritis (OA). METHODS: Precursor cells in the synovial tissue of 18 RA patients and 15 OA patients were identified by immunohistochemistry, morphometric analysis, and confocal laser scanning microscopy using the following phenotype markers: CD31, CD34, STRO-1, CD133, vascular endothelial growth factor receptor 2 (VEGFR-2), and CXCR4. The presence of CD31, CD34, CD133, VEGFR-2, and CXCR4 messenger RNA in the synovial tissue was determined by reverse transcriptase-polymerase chain reaction, and the message for CXCR4 was quantified by an RNase protection assay. RESULTS: A population of cells that expressed CD34 on their surface but lacked the endothelial cell marker CD31 was found in the synovial tissue of RA and OA patients. CD34+,CD31- cells were detected in close proximity to STRO-1+ and CD133+ cells, forming cell clusters in the sublining area of the synovial membrane. Within these cell clusters, CD34+,CD31- precursor cells were located on the inside surrounded by STRO-1+ cells and with CD133+ cells on the outside. CD34+ precursor cells in the cell layer expressed high levels of the chemokine receptor CXCR4, while VEGFR-2 was expressed on CD34+ and CD133+ cells, and alpha-smooth muscle actin was expressed on STRO-1+ cells. CONCLUSION: The presence of endothelial precursor cells in the synovial tissue of RA and OA patients provides evidence for vasculogenesis induced by precursor cells that arise in situ or from circulating progenitors.

Suprascapular nerve entrapment. A meta-analysis.

We performed a review of the literature between 1959 and 2001. We found 88 cases of suprascapular nerve entrapment, which fulfilled our inclusion criteria. Suprascapular nerve entrapment is rare and mainly occurs in patients under 40 years of age. Males are more likely to suffer from a ganglion compressing the nerve than females. If the patient's history reveals a trauma, it is more likely that the ligament is compromising the nerve. Ganglions usually cause isolated infraspinatus atrophy, whereas a combined atrophy of the supra- and infraspinatus muscles is more common in cases in which the nerve is compressed by the ligament.

Radiation synovectomy with (166)Ho-ferric hydroxide: a first experience.

UNLABELLED: Radiation synovectomy (RS) is indicated when conventional pharmacologic treatment of chronic synovitis has not relieved its symptoms. The use of radionuclides that are bound to ferric hydroxide (FH) particles has been shown to be effective and safe for this procedure. (166)Ho-FH macroaggregates offer promising properties for RS but there is a lack of clinical data. We investigated the efficacy and safety of (166)Ho-FH in a prospective clinical trial in patients suffering from chronic synovitis. METHODS: Twenty-four intraarticular injections were performed in 22 patients receiving a mean activity of 1.11 GBq (range, 0.77-1.24 GBq) (166)Ho-FH. Blood activity measurements and monitoring of activity distribution were performed by whole-body gamma-camera imaging for control of leakage 3 and 24 h after injection of (166)Ho-FH. The patients were evaluated clinically before RS, 1 wk and 1 mo after the treatment, and thereafter in 3-mo intervals by assessing joint effusion, pannus, local pain, range of motion, and the patient's satisfaction. RESULTS: In 18 of 24 treatments, no leakage to nontarget organs was visible, whereas small amounts of activity could be detected in the local inguinal lymph nodes in 6 patients and to the lungs and to the liver in 1 patient (<0.1%). In all cases leakage to the lymph nodes was <1%. Leakage to the blood was negligible. Clinically, 17 patients (71%) exhibited a complete or partial response. CONCLUSION: RS with (166)Ho-FH was safe and effective in patients with chronic synovitis of different origin. Controlled clinical trials are necessary to evaluate the therapeutic efficacy and safety compared with the treatment with other radionuclides and glucocorticosteroids.

Distinction between supraspinatus, infraspinatus and subscapularis tendon tears with ultrasound in 332 surgically confirmed cases.

The aim of this retrospective study was to determine the diagnostic value of preoperative ultrasonography for the characterisation of size and location of the involved tendons. in 332 consecutive patients who underwent surgery, all preoperative ultrasonographic reports were reviewed and ultrasound (US) and surgical findings were compared. Ultrasound criteria for cuff tears were complete nonvisualisation of the cuff tendons or localised absence and focal discontinuity. In all but 12 cases, US diagnoses corresponded with intraoperative findings (sensitivity 98%, confidence interval 95.1-99.3; specificity 93%, CI 85.7-97.1; accuracy 97%, CI 93.8-98.1). Size and location of the tear were correctly predicted in 69 of 96 cases (accuracy 87%, sensitivity 89%, specificity 87%). US demonstrated less extensive tears than observed at surgery in 18%. Ultrasonography was highly accurate and sensitive for detecting rotator cuff tears, but seems to be a method of limited value for evaluation of the size of cuff tears, in particular, for the detection of small tears.