Long-Term Durability of the CLS Femoral Prosthesis in Patients with Osteonecrosis of the Femoral Head

Ninety-five hips with cementless wedge-shaped tapered CLS stem were evaluated with a mean duration of 12.7 years (range, 10.7–17.3 years). All patients were young and diagnosed with osteonecrosis of the femoral head. The Harris hip score was 92 at the latest follow-up. A subsidence greater than 3 mm was found in 3 hips (3.2%). Focal femoral osteolysis was found in 12 hips (12.6%). Endosteal bone formation and bony pedestal were observed in 94 hips (98.9%) and in 26 hips (27.4%), respectively. With revision for stem loosening as the end point, the survivorship showed 98.9% (95% CI, range 96.9%–100%) at 13 years. Stem alignment and proximal femur morphology did not influence loosening of the stem (p > 0.05).     

Cementless total hip arthroplasty with ceramic-on-ceramic bearing in patients younger than 45 years with femoral-head osteonecrosis

Despite improvements in the quality of alumina ceramics, osteolysis has been reported anecdotally after total hip arthroplasty (THA) with use of a contemporary alumina-on-alumina ceramic bearing. The purpose of this study was to evaluate the clinical and radiographic outcomes of THA using alumina-on-alumina ceramic bearing and to determine osteolysis using radiographs and computed tomographic (CT) scans in young patients. Consecutive primary cementless THA using alumina-on-alumina ceramic bearing were performed in 64 patients (93 hips) who were younger than 45 years of age with femoral-head osteonecrosis. There were 55 men (84 hips) and nine women (nine hips). Average age was 38.2 (range 24–45) years. Average follow-up was 11.1 (range 10–13) years. Preoperative Harris Hip Score was 52.9 (range 22–58) points, which improved to 96 (range 85−100) points at the final follow-up examination. Two of 93 hips (2%) had clicking or squeaking sound. No hip had revision or aseptic loosening. Radiographs and CT scans demonstrated that no acetabular or femoral osteolysis was detected in any hip at the latest follow-up. Contemporary cementless acetabular and femoral components with alumina-on-alumina ceramic bearing couples function well with no osteolysis at a ten year minimum and average of 11.1-year follow-up in this series of young patients with femoral-head osteonecrosis.     

Cementless total hip arthroplasty with a metal-on-metal bearing in patients younger than 50 years

Total hip arthroplasty (THA) longevity is the primary concern in young patients. Metal-on-metal articulations were reintroduced to reduce polyethylene particle-induced osteolysis and improve survivorship; to date, based on issued reports, this strategy appears to have been successful. In this study, the authors investigated metal-on-metal articulation survivorship and osteolysis incidence in young patients (19-50 years old at index operations) and retrospectively reviewed cementless metal-on-metal THAs in 70 patients (78 hips) with a mean follow-up of 12.4 years. Metasul articulation was used with the Wagner acetabular component in all. Survivorship with revision for any cause was 98.7% (95% confidence interval, 98%-100%), and survivorship due to the development of osteolysis for any lesion was 97.5% (95% confidence interval, 95%-99%). Mean Harris hip score improved from 51 to 95 points at final follow-up. The findings of this study indicate that outcomes of cementless THA with a metal-on-metal bearing in young patients are satisfactory. However, longer-term studies in larger cohorts are required to determine whether metal-on-metal articulations are really a favorable option in young patients.     

Eleven- to 14-year follow-up results of cementless total hip arthroplasty using a third-generation alumina ceramic-on-ceramic bearing

To analyze long-term survivorship of cementless total hip arthroplasties (THAs) with the third-generation alumina ceramic-on-ceramic bearing, 100 consecutive THAs between 1996 and 1998 were reviewed. One cup and 2 stems were revised due to aseptic loosening. Another cup showed chipping of the acetabular liner at 8 years and required cup revision. The remaining hips showed stable bone ingrowth fixation with no osteolysis at the final follow-up. The 14-year survivorship as the end point of revision was 97.9% for the cup, 97.8% for the stem, and 95.7% for the overall implants, respectively. We conclude that cementless THA with the third-generation ceramic-on-ceramic hip bearing provided an excellent survivorship and eliminated periprosthetic osteolysis for 11 to 14 years.     

A cementless elastic monoblock socket in young patients: a ten to 18-year clinical and radiological follow-up

The survival of acetabular components depends on several factors: wear, osteolysis and septic or aseptic loosening. Osteolysis seems to be the main cause for concern in cementless arthroplasties. Acetabular osteolysis results from particle debris and segmental unloading of acetabular bone by rigid sockets. We investigated a cementless elastic monoblock socket with regard to acetabular osteolysis and aseptic loosening in a cohort of young patients. We evaluated 158 hip arthroplasties with a minimum follow-up of ten years (ten to 18) and a mean age of 42 years (18–50). The overall revision rate at 14 years was 80% with a 98% survival rate for aseptic loosening. The mean polyethylene wear rate was 0.11 mm/year. Progressive acetabular osteolysis was seen in 3% of patients evaluated. In conclusion, we found low pelvic osteolysis rates, acceptable overall wear rates, satisfactory overall survival and excellent survival rates for aseptic loosening of a cementless elastic monoblock socket in patients younger than 50 years. Ongoing tribology developments and knowledge about acetabular bone adaptations behind acetabular implants will further lower wear and osteolysis rates and optimise survival rates of cementless sockets.     

Long-Term Survivorship of Modular Cementless Femoral Stem in Complex Primary Total Hip Arthroplasty: A Concise Minimum 15-Year Follow-Up Report

BackgroundS-ROM hip is a well-established and versatile prosthesis that offers extensive metaphyseal and diaphyseal geometries providing solutions for a variety of surgical scenarios. The aim of this study is to report on long-term survivorship and radiographic outcomes of complex primary total hip arthroplasty (THA) using a modular cementless stem (S-ROM).MethodsRetrospective consecutive study was conducted of 167 patients (167 hips): 97 males and 70 females with average age at the time of surgery of 55 years (range 22-76). All patients underwent complex THA by the senior author from 1987 to 1999. Patients were identified using a prospective database. Demographic, clinical, and surgical data were collected from health records. All patients received a cementless acetabular component with a standard polyethylene liner. The primary outcome measure was survivorship beyond 15 years using stem revision for any cause as an end point. Secondary outcome measure was rate of radiographic loosening using Engh classification.ResultsOnly 3 patients required stem revision for aseptic loosening and 1 for periprosthetic fracture. Isolated acetabular revision was undertaken in 23 of 167 patients (13.8%) due to polythene wear, osteolysis, and aseptic loosening. Proximal femoral stress shielding (zone 1, 7) was noted in 34 of 167 hips (20.4%). Stable bony ingrowth was noted in 144 hips (86.2%) and the remaining 23 hips had stable fibrous ingrowth (13.8%). Using stem “any-cause revision” as an endpoint, the mean stem survivorship was 31.5 years (95% confidence interval 31.007-31.985) with 30-year estimated survivorship of 97.6%.ConclusionIn a single designer surgeon series, S-ROM stem has stood the test of time with long-term, 30-year survivorship of 97.6% and continues to play an important role in modern hip surgery providing longevity and versatility. However, further comparative long-term studies from independent centers are needed for a definitive conclusion.Level of EvidenceIV.     

Long-Term Outcomes for Cementless Anatomic Femoral Components,Compared by Area of Porous Coating,in Patients Younger Than 50 Years Treated for Hip Dysplasia

BackgroundWe investigated whether the proximal circumferential porous coating of cementless stems would make implant survival of >20 years possible in young patients.MethodsData for patients younger than 50 years with hip dysplasia who had an anatomic stem implanted with a proximal porous coating with hydroxyapatite/tricalcium phosphate were reviewed. Noncircumferential porous (non-C-type) stems were used in 17 hips (13 cases), and circumferential porous (C-type) stems were used in 87 hips (68 cases). Acetabular components with conventional polyethylene were used for all hips. The mean ages at surgery for patients with non-C-type stems and those with C-type stems were 43.3 and 44.7 years, respectively. Stems that had not loosened were retained at the time of acetabular revision. The average duration of follow-up for patients with non-C-type stems was 26.9 years and was 22.3 years for those with C-type stems.ResultsMean survival rates as determined by the Kaplan-Meier method were 74.9% at 20 years and 59.9% at 25 years for non-C-type stems and were 100% at 20 years and 94.0% at 25 years for C-type stems. The survivorship for C-type stems was significantly higher than that for non-C-type stems (P < .01). Focal osteolysis in the shoulder of 37 hips with C-type stems suppressed the spread of osteolysis to the distal femur.ConclusionAnatomic femoral stems with a circumferential porous coating provide excellent durability in patients with hip dysplasia who are 50 years of age or younger.Level of EvidenceTherapeutic Level IV.     

Midterm Results of Large Diameter Biolox Forte Ceramic Head on Delta Ceramic Liner Articulation in Total Hip Arthroplasty

Seventy-nine patients (94 hips), who underwent cementless alumina-on-alumina total hip arthroplasty (THA) with the use of a 36-mm delta ceramic liner-on-alumina ceramic femoral head, were followed for an average of 6.5 years (range, 5–7.7 years). All acetabular and femoral components were bone-ingrown and neither pelvic nor femoral osteolysis was identified until the latest follow-up. The survivorship with revision surgery as an endpoint was 97.9% (95% confidence interval = 100%–95%). Ceramic related complications such as fracture and squeaking did not occur in any patient. The mid-term results of cementless THA with this type of ceramic articulation are encouraging.     

A randomized trial of hydroxyapatite coated prostheses in total hip arthroplasty

In a prospective randomized trial, 62 consecutive primary cementless total hip arthroplasties in 55 patients were performed by one surgeon using either hydroxyapatite coated (35 hips) or nonhydroxyapatite coated femoral prostheses (27 hips). The dual tapered femoral stem had a Ti-6AI-4V plasma sprayed circumferential proximal porous coat applied to the proximal 1/3 of the stem. The middle 1/3 had a roughened blasted textured surface, and the distal 1/3 had a smooth surface. The hydroxyapatite coated femoral stems had an additional hydroxyapatite coating applied to the proximal porous coat with use of an air plasma process. The patients in the two groups were not significantly different regarding age (48.2 +/- 9.0 years hydroxyapatite group, 50.4 +/- 8.7 years control group), gender, Charnley class, or length of followup (4.4 +/- 0.7 years hydroxyapatite group, 4.9 +/- 1.0 years control group). Forty-nine patients (54 hips) were available for clinical followup, and 45 patients (50 hips) had radiographic followup. A minimum 3-year followup was recorded. To date, there have been no femoral prostheses failures. No femoral implant has migrated or subsided. Radiographically, the hydroxyapatite coated stems showed trends toward increased distal stem related cortical hypertrophy, increased cancellous condensation and less endosteal cavitation. Two nonhydroxyapatite coated stems had distal endosteal cavitation, whereas no hydroxyapatite coated stems did. There were two cases of acetabular osteolysis (revision in one) and two cases of acetabular cup migration (nonrevised), all occurring in the control group. The overall revision rate was 4%. There was no difference in Harris hip scores at 6 months (80.6 +/- 13.0 points hydroxyapatite group, 83.8 +/- 12.4 points control group) or at last followup (85.6 +/- 15.4 points hydroxyapatite group, 89.7 +/- 13.4 control group). The Harris hip pain scores also were not significantly different at 6 months or at last followup. Multiple linear regression analysis controlling for age, gender, and length of followup revealed no significant predictors of Harris hip or pain scores. The results of this study at an average of 4.6 years do not indicate a significant clinical advantage to the use of hydroxyapatite coated femoral prostheses in primary cementless total hip arthroplasty when judged by the criteria of Harris hip scores and femoral stem survivorship.