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).     

Clinical and radiographic evaluation of the Harris-Galante cup: incidence of wear and osteolysis at 7 to 9 years follow-up

A retrospective evaluation of the clinical and radiographic results of the Harris-Galante acetabular cups was performed in 112 patients with 127 total hip arthroplasties. Patients with 14 hips had died, and patients with 20 hips were lost to follow-up. A total of 82 patients with 93 hips was available for follow-up. There were 67 men and 45 women. The mean follow-up was 87 months (range, 48-113 months). There were a total of 9 revisions: 2 for recurrent dislocations, 1 for a loose cup, and 6 for wear and osteolysis. Radiographic evaluation demonstrated that 22 (24%) hips had periacetabular osteolysis, and 16 of these 22 (73%) were associated with the screws. Twenty-two hips (23%) demonstrated osteolytic lesions around the femoral stem. Mean femoral head displacement was of 1.00 mm (range, 0.40-4.5 mm) with a rate of 0.16 mm/yr (range, 0.05-0.44 mm/yr). The Harris-Galante socket has maintained a low implant failure rate at intermediate term, even in these young patients. As follow-up increases, wear of the polyethylene and periprosthetic osteolysis may become growing concerns.     

Total hip arthroplasty with a cementless acetabular component and a cemented femoral component in the treatment of Chinese patients with femoral head necrosis

The purpose of this study was to evaluate midterm clinical and radiographic outcomes associated with hybrid total hip arthroplasty in a consecutive series of 86 Chinese patients (93 hips) with osteonecrosis of the femoral head, which revealed that the mean Harris hip score increased from 39 +/- 6.0 points before operation to 90.4 +/- 4.6 points at the latest follow-up. There was pelvic osteolysis in one hip (1%), which required revision, and some small focal areas of femoral osteolysis in 12 hips (13%) were observed. The mean linear wear rate was 0.143 +/- 0.05 mm/y (0.02-0.45 mm/y). No loosening of the components was observed radiographically. The survival rate of the acetabular and femoral components for revision was 98% (95% confidence interval, 0.96-1.0) and 100% (95% confidence interval, 0.95-1.0). Hybrid total hip arthroplasty in patients with osteonecrosis of the femoral head had a satisfactory clinical and radiographic outcome at a minimum 5 years of follow-up. Because polyethylene wear and osteolysis cannot be avoided, the long-term effect should be further studied.     

The Exeter Universal stem: a minimum ten-year review from an independent centre

We reviewed 142 consecutive primary total hip replacements implanted into 123 patients between 1988 and 1993 using the Exeter Universal femoral stem. A total of 74 patients (88 hips) had survived for ten years or more and were reviewed at a mean of 12.7 years (10 to 17). There was no loss to follow-up. The rate of revision of the femoral component for aseptic loosening and osteolysis was 1.1% (1 stem), that for revision for any cause was 2.2% (2 stems), and for re-operation for any cause was 21.6% (19 hips). Re-operation was because of failure of the acetabular component in all but two hips. All but one femoral component subsided within the cement mantle to a mean of 1.52 mm (0 to 8.3) at the final follow-up. One further stem had subsided excessively (8 mm) and had lucent lines at the cement-stem and cement-bone interfaces. This was classified as a radiological failure and is awaiting revision. One stem was revised for deep infection and one for excessive peri-articular osteolysis. Defects of the cement mantle (Barrack grade C and D) were found in 28% of stems (25 hips), associated with increased subsidence (p = 0.01), but were not associated with endosteal lysis or failure. Peri-articular osteolysis was significantly related to the degree of polyethylene wear (p < 0.001), which was in turn associated with a younger age (p = 0.01) and male gender (p < 0.001). The use of the Exeter metal-backed acetabular component was a notable failure with 12 of 32 hips (37.5%) revised for loosening. The Harris-Galante components failed with excessive wear, osteolysis and dislocation with 15% revised (5 of 33 hips). Only one of 23 hips with a cemented Elite component (4%) was revised for loosening and osteolysis. Our findings show that the Exeter Universal stem implanted outside the originating centre has excellent medium-term results.     

No increased stem subsidence after arthroplasty in young patients with femoral head osteonecrosis: 41 patients followed for 1-9 years

BACKGROUND: Poor bone stock in patients with osteonecrosis of the femoral head may be a reason for poor outcome after hip replacement. One way of studying bone quality is to measure implant migration. We thus investigated the clinical and radiographic results of cementless THR in younger patients with femoral head osteonecrosis. PATIENTS AND METHODS: We studied hips in 41 patients (mean age 48 (25-63) years) with a cementless hip arthroplasty after late stage osteonecrosis. Clinical evaluation was by the Harris hip score, the WOMAC score and the SF-36 score. Stem subsidence was measured with the Ein Bild Roentgen Analyse femoral component analysis (EBRA-FCA) at 3, 12, 24, 60, and 72 months after operation. The average duration of follow-up was 7(1-9) years, with less than 2 years for 2 patients. RESULTS: There was no revision of any hip. No radiographic or clinical stem loosening was seen. After 60 months, the cementless stems showed a median subsidence of -0.7 mm (95% CI: -0.9 to -0.2). No femoral osteolysis occurred. Femoral radiolucent lines, all < 1 mm, were seen in 10 hips. At the latest follow-up the Harris hip score was 83 (23-100) points. INTERPRETATION: Our findings for porous-coated stems in patients with femoral osteonecrosis indicate no greater risk of stem subsidence and rate of osteolysis after an average of 7 years follow-up. Thus, we continue to use uncemented stems in younger patients with femoral osteonecrosis. However, continued follow-up will be necessary to evaluate the long-term outcome.     

Cementless Spotorno tapered titanium stems

We evaluated the clinical and radiographic results of the first consecutive 154 implantations of a cementless, double-tapered straight femoral stem (cementless Spotorno (CLS), Sulzer Orthopedics) in 141 patients under the age of 55 (mean 47 (13-55)) years. After a mean follow-up of 12 (10-15) years, 11 patients (11 hips) had died and 7 (7 hips) could not be located. 5 patients (5 hips) underwent femoral revision—1 for infection, 1 for periprosthetic fracture and 3 for aseptic loosening of the stem. The overall survival rate of the stem was 97% at 12 years (95% confidence limits, 93%-100%), and survival with femoral revision for aseptic loosening as an end point 98 (95-100)%. The survival rate of the acetabular components was 78 (71-85) % after 12 years. The median Harris hip score at follow-up was 84 points. None of the patients had thigh pain. Radiolucent lines in Gruen regions 1 and 7 were present in 21 hips (17%). 2 hips had radiolucent lines in regions 2-6 on anteroposterior (AP) radiographs. No femoral osteolysis was detected.

The mid- to long-term survival with this type of femoral component is excellent and compares favorably with cemented stems in this age group. However, the high rate of cup loosening and the low Harris hip scores are a concern in this subgroup of young patients.     

Total hip replacement with a cementless acetabular component and a cemented femoral component in patients younger than fifty years of age

BACKGROUND: We have been using hybrid total hip arthroplasty (a cementless acetabular component and a cemented stem) in young patients. The purpose of this study was to determine the prevalence of aseptic loosening, polyethylene wear, and osteolysis after the use of this technique. METHODS: We studied a prospective consecutive series of sixty-four primary hybrid total hip replacements in fifty-five patients younger than fifty years old. There were forty-three men and twelve women; the average age at the time of the index operation was 43.4 years. The average duration of follow-up was 9.4 years. We used a cementless acetabular component without screw-holes and a cemented femoral component with a 22-mm head in all hips. Clinical follow-up with use of Harris hip ratings and radiographic follow-up were performed at six weeks; at three, six, and twelve months; and yearly thereafter. The sequential annual linear and volumetric wear rates were measured, and bone-remodeling and osteolysis were assessed. RESULTS: The mean preoperative Harris hip score was 44 points, which increased to 95 points at the time of final follow-up. No hip had aseptic loosening. One hip (2%) was revised because of late infection. The average linear wear (and standard deviation) was 0.96 +/- 0.066 mm, with an average annual rate of 0.096 +/- 0.013 mm. The average volumetric wear was 364.7 +/- 25.2 mm (3), with an average annual rate of 43.4 +/- 3.5 mm (3). Six hips (9%) had an osteolytic lesion of <1 cm in diameter in the calcar femorale (zone 7). CONCLUSIONS: Our results show that a hybrid arthroplasty with a cementless acetabular component and a smooth cemented femoral component (Ra, 0.6 mm) is effective for primary total hip replacement in young patients. Although there was no aseptic loosening and a low prevalence of osteolysis at the latest follow-up evaluation, the high rates of linear and volumetric wear of the polyethylene liner in these young patients remain a concern.     

Cementless total hip replacement using second-generation components: a 12- to 16-year follow-up

We reviewed 123 second-generation uncemented total hip replacements performed on 115 patients by a single surgeon between 1993 and 1994. The acetabular component used in all cases was a fully porous-coated threaded hemispheric titanium shell (T-Tap ST) with a calcium ion stearate-free, isostatically compression-moulded polyethylene liner. The titanium femoral component used was a Taperloc with a reduced distal stem. No patient was lost to follow-up. Complete clinical and radiological follow-up was obtained for all 123 hips at a mean of 14 years (12 to 16). One femoral component was revised after a fracture, and three acetabular components for aseptic loosening. No additional femoral or acetabular components were judged loose by radiological criteria. Mild proximal femoral osteolysis was identified in two hips and minor acetabular osteolysis was present in four. The mean rate of penetration of the femoral head was 0.036 mm/year (0.000 to 0.227). These findings suggest that refinements in component design may be associated with excellent long-term fixation in cementless primary total hip replacement.     

A conservative femoral replacement for total hip arthroplasty. A prospective study

Between 1985 and 1993, 146 patients (162 hips) had total hip replacement (THR) using a conservative uncemented femoral component. The mean age of the patients was 50.8 years and the mean follow-up was 6.2 years (2 to 13). One patient was lost to follow-up, one died within two years of surgery and one had a revision procedure after a fracture sustained in a road-traffic accident. For the remaining 159, Kaplan-Meier survival analysis was calculated for the incidence of revision because of mechanical loosening or osteolysis. Survival without mechanical loosening at both five and ten years was 98.2%. Survival without osteolysis was 99% at five and 91% at ten years. The Harris hip score improved from a mean of 66.3 before to 90.4 at follow-up. Of particular note is the lack of thigh pain in this group. Radiological analysis showed that 139 stems (88%) had no measurable subsidence, 8 (5%) had less than 2 mm and 12 (7%) had more than 2 mm. Two of the eight and one of the 12 were revised for mechanical loosening. Nine hips were revised for late loosening associated with osteolysis. No reaming of the femoral canal was associated with statistically significant less blood loss compared with a comparable control group of uncemented implants (p < 0.0001). Our study suggests that using a conservative femoral implant does not protect against wear debris but the reliable mechanical stability (98.2%) makes this an attractive design of implant particularly for young patients.     

Ten-year survival of the MS-30 matt-surfaced cemented stem

The Morscher-Spotorno (MS-30) femoral stem is a stainless-steel, straight, three-dimensionally tapered, collarless implant for cemented fixation in total hip replacement.We report the results at ten years of a consecutive series of 124 total hip replacements in 121 patients with the matt-surfaced MS-30 stem and an alumina ceramic head of 28-mm diameter. All the stems were fixed with Palacos bone cement with gentamicin using a modern cementing technique. They were combined with an uncemented, press-fit cup. The mean period of observation was 10.2 years (8.3 to 12.1) and no patient was lost to follow-up. Twenty-seven patients (22%) died with the implant in situ. Nine could only be interviewed by telephone. We included 85 patients with 88 hips in the clinical and radiological follow-up examinations.None of the stems or cups had been revised. The Harris hip score was excellent or good in 97% (85 hips) and moderate in 3% (three hips). Radiologically, six hips (6.8%) had osteolysis adjacent to the stem, mostly in Gruen zone 7. Twenty (22.7%) showed one or more radiolucent lines. Twenty-two stems (25%) had subsided by 2 mm to 5 mm. In these cases two showed osteolysis (9.1%) with subsidence and four without (6.1%). Radiolucent lines were seen in seven with migration (31.8%) and in 13 without (19.7%). No infections and no acetabular osteolysis were observed.The clinical results were excellent with survivorship after ten years of 100% and only a slightly statistically non-significant higher rate of osteolysis and radiolucency in cases of subsidence.     

No increased stem subsidence after arthroplasty in young patients with femoral head osteonecrosis:41 patients followed for 1–9 years

Background?Poor bone stock in patients with osteonecrosis of the femoral head may be a reason for poor outcome after hip replacement. One way of studying bone quality is to measure implant migration. We thus investigated the clinical and radiographic results of cementless THR in younger patients with femoral head osteonecrosis.

Patients and methods?We studied hips in 41 patients (mean age 48 (25–63) years) with a cementless hip arthroplasty after late stage osteonecrosis. Clinical evaluation was by the Harris hip score, the WOMAC score and the SF-36 score. Stem subsidence was measured with the Ein Bild Roentgen Analyse femoral component analysis (EBRA-FCA) at 3, 12, 24, 60, and 72 months after operation. The average duration of follow-up was 7(1–9) years, with less than 2 years for 2 patients.

Results?There was no revision of any hip. No radiographic or clinical stem loosening was seen. After 60 months, the cementless stems showed a median subsidence of –0.7?mm (95% CI: –0.9 to –0.2). No femoral osteolysis occurred. Femoral radiolucent lines, all < 1?mm, were seen in 10 hips. At the latest follow-up the Harris hip score was 83 (23–100) points.

Interpretation?Our findings for porous-coated stems in patients with femoral osteonecrosis indicate no greater risk of stem subsidence and rate of osteolysis after an average of 7 years follow-up. Thus, we continue to use uncemented stems in younger patients with femoral osteonecrosis. However, continued follow-up will be necessary to evaluate the long-term outcome.     

Nineteen Year Results of THA Using Modular 9 mm S-ROM Femoral Component in Patients With Small Femoral Canals

A retrospective analysis was undertaken of 30 consecutive THA performed in 25 patients with hypoplastic proximal femurs, who had received a 9-mm uncemented modular S-ROM stem. The mean patient age was 42 years (17–69 years), mean height was 152.5cm (130–170.5 cm), mean weight was 63 kg (39–90 kg), and mean follow-up period was 19 years (range, 12–23 years). Subsidence was seen in 2 hips, with asymptomatic femoral osteolysis present in 11 hips; overall survival of the femoral stem was 93.3%, with two revisions of the femoral component required for aseptic loosening. After a mean follow-up of 19 years, the use of the S-ROM 9 mm femoral stem in the patient with the small femur was associated with a low revision rate due to aseptic loosening of the stem.     

Precoated femoral component in total hip arthroplasty. Results of 5- to 9-year followup.

One hundred nineteen consecutive primary hybrid total hip arthroplasties with a precoated femoral component were performed by one surgeon in 100 patients and followed up prospectively. Ninety-eight hips in 82 patients (mean age, 67 years) were evaluated clinically and radiographically at a mean of 6.5 years (range, 5-9 years). The hips were evaluated clinically using the Harris hip score, and radiographs were evaluated for femoral cement grade, loosening, and osteolysis. Ninety-five hips remained in place at the most recent followup. Two femoral components were revised for definite loosening, and one well fixed femoral component was removed because of late hematogenous infection. Excluding the three hips that were revised, the clinical result was excellent or good in 79 hips (83%), fair in 12 hips (13%), and poor in four hips (4%). All other femoral components were well fixed. There were defects of the cement mantles (C1 and C2) in 90 hips. No femoral component had a stem and cement radiolucent line. Focal femoral osteolysis was seen in only two hips. One acetabular component was removed at 5 years because of late hematogenous infection. One acetabular component had asymptomatic migration. The remaining 96 acetabular components were well fixed. Focal acetabular osteolysis was present in four hips. The mean linear polyethylene wear rate was 0.06 (+/- 0.05) mm per year. In contrast to other reports of early failure and osteolysis, the use of a precoated femoral component in this study did not adversely affect the fixation of hybrid total hip arthroplasty, with definite failure of only 2% (two of 98) of the femoral components.     

Cementless total hip arthroplasty in Chinese patients with osteonecrosis of the femoral head

This study was designed to evaluate the midterm (> or = 5 years) clinical and radiographic outcomes of the cementless total hip arthroplasty in 64 Chinese patients (72 hips), which revealed that the mean Harris hip score increased from an average of 44.0 points before operation to 92.4 points at the last follow-up. Excellent results were achieved in 60 hips (83%). No loosening of the components was observed radiographically. No revision of the femoral components was required. Only one focal area of pelvic osteolysis in 1 hip (1%), which requires a revision, and some small focal areas of femoral osteolysis in 12 hips (17%) were observed. The mean linear wear rate was 0.125 mm/y. The survival rate of the acetabular and femoral components for radiographic loosening was 100% (95% confidence interval, 0.93-1.0) and for revision was 98.61% (95% confidence interval, 0.95-1.0). This study indicated that the cementless total hip arthroplasty in patients with osteonecrosis of the femoral head has a satisfactory midterm clinical and radiographic outcomes, but the long-term effect should be further studied.     

Contemporary total hip arthroplasty with and without cement in patients with osteonecrosis of the femoral head

BACKGROUND: The rate of failure of primary total hip arthroplasty in patients with osteonecrosis of the femoral head is higher than that in patients with osteoarthritis. The purpose of this prospective study was to document the clinical and radiographic results of arthroplasty with so-called third-generation cementing and the results of second-generation cementless total hip arthroplasty in ninety-eight consecutive patients with osteonecrosis of the femoral head. METHODS: Fifty patients who had had simultaneous bilateral total hip arthroplasty with a cemented stem in one hip and a cementless stem in the other and forty-eight patients who had had a unilateral total hip arthroplasty with a cementless stem were included in the study. A cementless acetabular component was used in all hips. The presumed cause of the osteonecrosis was ethanol abuse in fifty-seven patients, unknown in twenty-seven, fracture of the femoral neck in nine, and steroid use in five. There were eighty men and eighteen women. The mean age at the time of the arthroplasty was 47.3 years (range, twenty-six to fifty-eight years). Clinical and radiographic evaluations were performed preoperatively; at six weeks; at three, six, and twelve months; and yearly thereafter. The average duration of follow-up was 9.3 years. RESULTS: The average Harris hip scores in the group treated with unilateral arthroplasty (97 points) and the group treated with bilateral arthroplasty (94 points) were similar at the time of final follow-up. They were also similar between the group treated with cement (mean, 96 points) and that treated without cement (95 points). No component had aseptic loosening in either group. In one hip, a cemented femoral stem (2%) and a cementless cup were revised because of infection. Two cementless stems (2%) were revised because of fracture of the proximal part of the femur with loosening of the stem. Annual wear of the polyethylene liner averaged 0.22 mm in the group treated with cement (a zirconia head) and 0.14 mm in the group treated without cement (a cobalt-chromium head). The prevalence of osteolysis in zones 1 and 7 of the femur was 16% in the group treated with cement and 24% in the group treated without cement. CONCLUSIONS: Advancements in surgical technique and better designs have greatly improved the long-term survival of cemented and cementless implants in young patients with osteonecrosis of the femoral head. Although there was no aseptic loosening of the components, a high rate of linear wear of the polyethylene liner and a high rate of osteolysis in these high-risk young patients remain challenging problems.     

Primary total hip arthroplasty with the AML total hip prosthesis

Primary total hip arthroplasty using an uncemented AML total hip prosthesis (trispiked cup and a 4/5 porous coated stem) was performed in 50 patients (52 hips). The average age of the patients at the time of surgery was 47.6 years (range, 19-68 years), and the diagnosis was osteonecrosis of the femoral head in 18 hips, osteoarthritis in 16, fracture of the femoral neck in 14, osteoarthrosis secondary to childhood pyogenic arthritis in two, childhood tuberculous arthritis in one, and traumatic arthritis in one. The average followup was 11.3 years (range, 11-12 years). The average preoperative Harris Hip Score was 59 points, which improved to 90 points. Twenty-five (48%) hips had excellent results, 14 (27%) had good results, three (6%) had fair results, and 10 (19%) had poor results. The overall rate of revision was 15% (eight hips). The rate of revision of the femoral component was 2% (one hip), and the rate of revision of the acetabular component was 15% (eight hips). Twenty (38%) hips had acetabular and femoral osteolysis. Nine (17%) hips had femoral osteolysis only. Thirty-four (65%) hips had an average of 3.3 mm (range, 2-12 mm) of wear in the polyethylene liner. The average wear rate was 0.29 mm (range, 0.17 to 1.04 mm) per year.     

Cementless alumina-on-alumina total hip arthroplasty in patients younger than 50 years: a 5-year minimum follow-up study

Sixty-seven patients (78 hips) who were younger than 50 years underwent cementless total hip arthroplasty using a porous-coated acetabular cup, an alumina liner, a 28-mm alumina head, and a proximally porous-coated femoral stem. One patient (1 hip) died and 2 patients (3 hips) were lost to follow-up. The remaining 64 patients (74 hips) were followed for 5 to 6 years. Their mean age at the index operation was 37 years. The mean Harris hip score was 94 points at the time of final follow-up. Four patients (4 hips) had mild thigh pain. All acetabular and femoral components were bone-ingrown, and neither pelvic nor femoral osteolysis was identified. No fracture of the ceramic liner or head was identified. Wear of the ceramic components was undetectable in 27 hips in which measurement was possible.     

Periacetabular osteolysis is the problem in contemporary total hip arthroplasty in young patients

We retrospectively reviewed 474 patients (492 hips) with a contemporary cemented total hip arthroplasty (THA) (mean age, 38.9 years) and 504 patients (532 hips) with a cementless THA (mean age, 39.3 years). Patients were evaluated clinically and radiographically. The mean follow-up was similar (14.5 vs 14.8 years) in both groups. The mean postoperative Harris hip scores (93.6 vs 94.7 points), the mean Western Ontario and McMaster Universities Osteoarthritis Index scores (12 vs 13 points), and the mean University of California, Los Angeles activity scores (6.9 vs 7.1 points) were similar between the 2 groups. Incidence of acetabular osteolysis (16% vs 20%) and femoral osteolysis (8% vs 9%) was similar between the 2 groups. Survivorship of cup (86% vs 82%) and stem (98% vs 98.5%) was similar between the 2 groups. Periacetabular osteolysis constitutes the major challenge in modern THAs in young patients.