High prevalence of noise following Delta ceramic-on-ceramic total hip arthroplasty.

AIMS: We evaluated the short-term functional outcome and prevalence of bearing-specific generation of audible noise in 301 patients (336 hips) operated on with fourth generation (Delta) medium diameter head, ceramic-on-ceramic (CoC) total hip arthroplasties (THAs). PATIENTS AND METHODS: There were 191 female (63%) and 110 male patients (37%) with a mean age of 61 years (29 to 78) and mean follow-up of 2.1 years (1.3 to 3.4). Patients completed three questionnaires: Oxford Hip Score (OHS), Research and Development 36-item health survey (RAND-36) and a noise-specific symptom questionnaire. Plain radiographs were also analysed. A total of three hips (0.9%) were revised. RESULTS: There were 52 patients (54 hips, 17%) who reported noise, and in 25 (48%) of them the noise was frequently heard. In the multiple regression analysis, the only independent risk factor for noise was a specific THA brand, with a threefold increased risk (95% confidence intervals 1.39 to 6.45, p = 0.005) of noise compared with the reference THA brand. Patients with noisy hips had lower median OHS (43 versus 46.5, p = 0.002) and their physical functioning (p = 0.021) subscale in RAND-36 was reduced. CONCLUSION: Noise was surprisingly common in this population. Cite this article: Bone Joint J 2017;99-B:44-50.

The use of a biodegradable mesh plate to augment grafting of an acetabular defect: Laboratory investigation and clinical pilot study.

We used a biodegradable mesh to convert an acetabular defect into a contained defect in six patients at total hip replacement. Their mean age was 61 years (46 to 69). The mean follow-up was 32 months (19 to 50). Before clinical use, the strength retention and hydrolytic in vitro degradation properties of the implants were studied in the laboratory over a two-year period. A successful clinical outcome was determined by the radiological findings and the Harris hip score. All the patients had a satisfactory outcome and no mechanical failures or other complications were observed. No protrusion of any of the impacted grafts was observed beyond the mesh. According to our preliminary laboratory and clinical results the biodegradable mesh is suitable for augmenting uncontained acetabular defects in which the primary stability of the implanted acetabular component is provided by the host bone. In the case of defects of the acetabular floor this new application provides a safe method of preventing graft material from protruding excessively into the pelvis and the mesh seems to tolerate bone-impaction grafting in selected patients with primary and revision total hip replacement.

Spacer prostheses in two-stage revision of infected knee arthroplasty.

At present, no consensus exists on the best spacer alternative for the management of two-stage exchange arthroplasty of infected knee arthroplasties. In this retrospective study, patient records of 24 patients, who had undergone two-stage revisions in which resterilised prosthetic components were used as spacers, were reviewed. The outcome was compared to that of operations performed during the same period (1993-2003) using cement spacers (n=10). With an average follow-up of 32 months, control of infection was achieved in 26 cases (76%), with good or excellent clinical outcome in 19 cases (56%). Treatment failed and resulted in amputation at the level of the thigh before reimplantation in one case. Three patients did not undergo reimplantation. In four cases (12%) infection relapsed. The reinfection rate did not differ between the two spacer groups. Patients treated with resterilised components had a superior range of motion during the period between the two stages. Operative time was shorter and there was less blood loss in the reimplantation arthroplasty when a prosthetic spacer was used. We consider resterilised prosthetic components a safe and effective alternative to cement spacers in the management of infected knee arthroplasties.

Revision total knee arthroplasty with the Total Condylar III system in inflammatory arthritis.

We report a consecutive series of 16 revision total knee arthroplasties using the Total Condylar III system in 14 patients with inflammatory arthritis which were performed between 1994 and 2000. There were 11 women and three men with a mean age of 59 years (36 to 78). The patients were followed up for 74 months (44 to 122). The mean pre-operative Knee Society score of 37 points (0 to 77) improved to 88 (61 to 100) at follow-up (t-test, p < 0.001) indicating very good overall results. The mean range of flexion improved from 62 degrees (0 degrees to 120 degrees) to 98 degrees (0 degrees to 145 degrees) (t-test, p < 0.05) allowing the patients to stand from a sitting position. The mean Knee Society pain score improved from 22 (10 to 45) to 44 (20 to 50) (t-test, p < 0.05). No knee had definite loosening, although five showed asymptomatic radiolucent lines. Complications were seen in three cases, comprising patellar pain, patellar fracture and infection. These results suggest that the Total Condylar III system can be used successfully in revision total knee arthroplasty in inflammatory arthritis.

Bipolar hemiartroplasty in the treatment of hip fracture: are special centres necessary for the optimal outcome?

BACKGROUND AND AIMS: This study compares retrospectively clinical follow-up of 72 bipolar arthroplasties made either by specialist surgeons or residents. MATERIAL AND METHODS: 72 patients with a life-expectancy of more than three years were selected to have bipolar arthroplasty for the treatment of femoral collum fracture at Tampere University Hospital district during 1993-1995. The average age of the patients was 70 (47-92) years. All patients were followed at least 4 years for mortality as well as primary and late complications. A group of 49 (68%) patients could be followed more carefully by clinical examination, by questionaire or by phone. RESULTS: 20 (28%) patients died during the first three years after surgery and four (6%) patients were re-operated. The bare preoperative clinical estimation made by the senior consultant surgeon did not predict good enough the life expectancy of the patients. Four patients had been revised, all operated by a senior surgeon. There were no revisions among the patients operated by junior doctors. No statistical differences were found between the patients operated by junior or senior surgeons or between cemented and cementless prostheses in pain, walking distances, limping, getting in to a car, need of support or sitting in high or normal chair. CONCLUSIONS: The bipolar arthroplasty was found to give reproducible results also when residents take the responsibility of hip fracture treatment.

Intermediate-term clinical and radiographic results of Synatomic and AGC knee prostheses.

This study compared two total knee prostheses to determine whether the clinical and radiographic outcomes were different, focusing primarily on the patellofemoral articulation. The study group was comprised of 75 Synatomic (short-stemmed, anatomic VF type) and 79 AGC 2000 (universal, nonanatomic) prostheses. Patients underwent follow-up for an average of 63 and 50 months, respectively. At latest follow-up, the mean knee joint score was 84.4 in the Synatomic and 86.5 in the AGC group. Mean knee function scores were 63.5 and 63.4, respectively. No statistically significant difference was noted between the two prostheses.

The clinical and radiological outcome of the rotating hinged knee prostheses in the long-term.

BACKGROUND AND AIMS: Opinions about hinged knee prostheses vary a lot in different studies. We wanted to examine our series in order to gain long-term information about this kind of knee prosthesis. MATERIAL AND METHODS: Forty-eight (18 Kinematic Hinge and 30 Link Endo Model) rotating hinged knee prostheses were implanted in the Hospital of Invalid Foundation. All knees were retrospectively followed up for an average of 66.3 months and examined for clinical or radiological factors indicating the overall outcome. RESULTS: In the latest review there were 10 patients (20.8%) regarded as having unsatisfactory and 35 patients (79.2%) satisfactory results. Eighty-four per cent of the patients were subjectively satisfied with the operation, mostly because of the painless result. CONCLUSIONS: Taking into account the very poor initial status of these patients, we recommend the rotating hinged prostheses still to be used in severely instable knees awaiting revision.

A five to seven years follow-up of 102 cementless Synatomic knee arthroplasties.

One hundred and two cementless Synatomic total knee prostheses were implanted in our hospital between January 1987 and October 1989. All knees were retrospectively followed up for five to seven years and examined for both pre- and postoperative clinical or radiological factors indicating aseptic loosening. The overall survival of the implants was 88.6%. The mean preoperative tibiofemoral angle of 178.5 degrees was found to be corrected immediately postoperatively to 183.4 and at the latest review to 182.3 degrees, with a slight shift towards varus which in the case of femoral component further increased during follow-up (P < 0.05). No correlation was found between tibiofemoral alignment and overall joint survival. Improvement of the preoperative marked (over 12 degrees) tibiofemoral valgus alignment correlated to clinical failure (P < 0.05). No such correlation was observed in pronounced varus knees (P = 0.897). A clear correlation was observed between the clinical outcome and the knee joint (P < 0.05) and function (P < 0.05) scores. Especially pain correlated closely with survival.

Glass-ceramic-coated titanium hip endoprosthesis. Experimental study in rabbits.

Titanium alloy hip endoprostheses coated with a bioactive glass ceramic (BGC) were followed in rabbits. All test endoprostheses remained stable, and image analysis showed an average of 78% bonding of the BGC-coated implants to bone at 52 weeks. The uncoated Ti-alloy controls demonstrated an average of 37% bone coverage after 52 weeks. By scanning electron microscopy the thickness of the BGC reaction layer was found to stabilize at 60 microns after bioactive bone bonding. The results indicate that the BGC coating must be thicker than the reaction layer to prevent detachment from the core metal.

Proliferative cell response to loosening of total hip replacements: a cytofluorographic cell cycle analysis.

Monocyte/macrophages and fibroblasts are the major reactive cells in the periprosthetic connective tissue in a loose totally replaced hip. Monocyte/macrophages are bone-marrow-derived, hematogenous cells, whereas mesenchymal fibroblasts replenish by local proliferation. The cell-cycle-phase frequency distribution therefore reflects the local mitotic fibroblast response to the loose total hip replacement (THR) implant. In 13 patients who underwent revision of a loose THR implant, most of the local cells were in the resting G0/G1 phase (88.1 +/- 6.3%, mean +/- SD), whereas 8.6 +/- 3.7% were in the S phase of the cycle, and 3.4 +/- 2.9% had already reached the G2/M phase. The highest DNA values were recorded in an osteoarthritic patient undergoing revision 4 years after the primary uncemented THR, while the lowest values were observed in a rheumatoid arthritis patient with a loose cemented prosthesis 15 years after the primary operation. The results suggest that the local proliferative fibroblast response in general is uniform and does not seem to depend on the type of prosthesis or the use of cement. The responses in aggressive granulomatous-type loosening and the common type of loosening were similar.