Clinical and radiological results of the collarless polished tapered stem at 15 years follow-up

We prospectively followed 191 consecutive collarless polished tapered (CPT) femoral stems, implanted in 175 patients who had a mean age at operation of 64.5 years (21 to 85). At a mean follow-up of 15.9 years (14 to 17.5), 86 patients (95 hips) were still alive. The fate of all original stems is known. The 16-year survivorship with re-operation for any reason was 80.7% (95% confidence interval 72 to 89.4). There was no loss to follow-up, with clinical data available on all 95 hips and radiological assessment performed on 90 hips (95%). At latest follow-up, the mean Harris hip score was 78 (28 to 100) and the mean Oxford hip score was 36 (15 to 48). Stems subsided within the cement mantle, with a mean subsidence of 2.1 mm (0.4 to 19.2). Among the original cohort, only one stem (0.5%) has been revised due to aseptic loosening. In total seven stems were revised for any cause, of which four revisions were required for infection following revision of the acetabular component. A total of 21?patients (11%) required some sort of revision procedure; all except three of these resulted from failure of the acetabular component. Cemented acetabular components had a significantly lower revision burden (three hips, 2.7%) than Harris Galante uncemented components (17 hips, 21.8%) (p < 0.001). The CPT stem continues to provide excellent radiological and clinical outcomes at 15?years following implantation. Its results are consistent with other polished tapered stem designs.     

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.     

Collarless polished tapered stem: clinical and radiological follow-up over 5 years

The clinical and radiologic outcome of a cemented, polished, tapered stem (CPT), implanted using contemporary cementing techniques in 108 consecutive operated hips in 100 patients (68 women and 32 men, aged 19 to 83 years at the time of surgery [mean, 65 years]) was assessed after >5 years. The Harris hip scores were good or excellent in 96% of the patients. Stem subsidence measured by the computer-assisted method described by Braud and Freeman was at a mean rate of 0.44 mm/y, 1.08 mm during the first year, and stabilizing to a mean total of 2.18 mm at >5 years. Subsidence was related inversely to the completeness of the cement mantle but did not correlate with the clinical or radiologic outcome. This study confirms that collarless, polished, tapered stems subside within the cement mantle but without loosening and that the CPT performs at least as well as the Exeter stem.     

Hip arthroplasty with proximal transmission of force: first clinical results with a new partially cemented femoral stem

BACKGROUND: Proximal stem fixation by partial cementing is a new concept in hip arthroplasty. We conducted a prospective clinical and radiological analysis to evaluate the preliminary outcome of this new technique with the Option 3000 stem (Mathys Orthopaedics, Bettlach, Switzerland). METHODS AND FOCUS: One hundred and thirty-three hip replacements in 123 patients have been performed between 1996 and 2003: All of them were followed up regularly both clinically and radiological and 53 were analysed with the EBRA-FCA method. Eighty-six patients with 95 hips could be seen in August 2004. At this point of time, the mean follow-up time was 61 months (5.08 years) with a maximum of 100 months (8.33 years) RESULTS: The clinical data reported an average Harris Hip Score of 85.5. Nine stems had to be exchanged over the period of study. The EBRA-FCA analysis reported a mean subsidence less than 1.5 mm after 2 years, then an average stable subsidence of 2.4 mm. So the results are similar to the early results obtained with other fixation concepts and the long-term results appear promising.     

The relationship between stem subsidence and improvement in the radiolucency in polished tapered stems

We studied the relationship between stem subsidence and improvement in the initial radiolucency at the bone-cement interface in polished- and rough-surface stems. Stem subsidence was seen in 34 of 42 hips (81.0%), and improvement in the initial radiolucency was seen in 15 hips (35.7%) in collarless polished tapered stems at 1 year after operation. In polished stems, stem subsidence in cases with improvement in the initial radiolucency was significantly greater than in those with no change (average 1.12 mm and 0.48 mm, P<0.005). In rough-surface stems partially coated with polymethylmethacrylate (VerSys Cemented Plus), no stem subsidence and no improvement in the initial radiolucency was seen. In polished stems, stem subsidence leads to cement creep and compressive force on the bone-cement interface and can improve the initial radiolucency.     

A comparison of collared and collarless femoral components in primary cemented total hip arthroplasty: a randomized clinical trial

Between July 1986 and November 1989, 437 consecutive primary cemented total hip arthroplasties were performed using a straight-stemmed titanium alloy femoral component. Collared and collarless versions of this identical stem were randomly chosen by computer allowing a comparison between 213 collared stems (198 patients) and 224 collarless stems (209 patients). Diagnosis, sex, weight, and average age (72.8 years, collared; 72.0 years, collarless) were similar. Follow-up averaged 76 months (collared) and 72 months (collarless) with 49 patients followed for at least 10 years. Calcar-collar contact was noted in 205 hips (96%) on the initial postoperative radiograph. Early complications, including dislocations (5% each group), were similar. Late complications included 3 deep infections (2 collared, 1 collarless) and 2 postoperative femur fractures (1 each). Hip scores at the most recent follow-up averaged 91.2 and 90.1 in the collared and collarless groups. No or slight pain was noted in 93% of collared and 91.5% of collarless hips. Although no radiographic differences were noted in distal cortical hypertrophy, stem subsidence, and osteolysis, collarless hips lost significantly more medial femoral neck cortical bone (average 0.90 mm vs 0.63 mm). A higher incidence of radiolucent lines in femoral zone VI (20.7% vs 9.4%) was also noted in collarless hips.     

Femoral impaction bone allografting with an Exeter cemented collarless, polished, tapered stem in revision hip replacement: a mean follow-up of 10.5 years

Femoral impaction bone allografting has been developed as a means of restoring bone stock in revision total hip replacement. We report the results of 75 consecutive patients (75 hips) with a mean age of 68 years (35 to 87) who underwent impaction grafting using the Exeter collarless, polished, tapered femoral stem between 1992 and 1998. The mean follow-up period was 10.5 years (6.3 to 14.1). The median pre-operative bone defect score was 3 (interquartile range (IQR) 2 to 3) using the Endo-Klinik classification. The median subsidence at one year post-operatively was 2 mm (IQR 1 to 3). At the final review the median Harris hip score was 80.6 (IQR 67.6 to 88.9) and the median subsidence 2 mm (IQR 1 to 4). Incorporation of the allograft into trabecular bone and secondary remodelling were noted radiologically at the final follow-up in 87% (393 of 452 zones) and 40% (181 of 452 zones), respectively. Subsidence of the Exeter stem correlated with the pre-operative Endo-Klinik bone loss score (p = 0.037). The degree of subsidence at one year had a strong association with long-term subsidence (p < 0.001). There was a significant correlation between previous revision surgery and a poor Harris Hip score (p = 0.028), and those who had undergone previous revision surgery for infection had a higher risk of complications (p = 0.048). Survivorship at 10.5 years with any further femoral operation as the end-point was 92% (95% confidence interval 82 to 97).     

Primary exeter total hip arthroplasty in patients with small femurs: a minimal of 10 years follow-up

One hundred and twelve hips in 101 Chinese patients received primary cemented Exeter total hip arthroplasty (Howmedica, Hong Kong). The implant had a collarless, double-tapered and polished stem. Seventy-five hips in 67 patients were available for assessment. The average age at operation was 63.7 years. The commonest diagnosis was avascular necrosis. The average follow-up was 12.8 years (range, 10 to 16.5 years). The Harris score improved from a preoperative average of 39.8 to 82.3 at the last follow-up. Stem subsidence within the cement mantle occurred in 9.3% of the cases and none of these stems had other evidence of loosening. Eight hips (six stems and two cups) in seven patients were revised because of loosening at five to 14 years postoperatively. The survival rate was 93.3% and 86% at 10 and 15 years respectively. Oversized stems and incomplete cement mantle might account for the loosening. Stems of a smaller size have been made available to this population and hopefully this will improve the results further.     

Long-Term Outcomes of Revision Total Hip Arthroplasty Using a Tapered and Fluted Modular Stem: A Mean Follow-Up of 16 Years

BackgroundTapered modular stems are increasingly used in revision total hip arthroplasty (THA) with deficient femoral bone stock. This study aimed to report the long-term outcomes of revision THA using a tapered and fluted modular stem.MethodsBetween December 1998 and February 2006, 113 revision THAs (110 patients) were performed with a tapered and fluted modular stem at a single institution. Hip radiographs were used to identify stem subsidence, stability, and femoral radiolucency. Final outcomes were assessed in 72 hips (70 patients), with a minimum follow-up of 10 years.ResultsThe mean follow-up duration was 16 years (range, 10-23). At the final evaluation, the Harris Hip Score improved from a mean of 41 points (range, 10-72) preoperatively to 83 points (range, 56-100) (P < .001). Six femoral re-revisions were performed for the following reasons: 1 aseptic loosening, 2 stem fractures, and 3 infections. One stem fracture occurred at the modular junction after 14 years, and the other at a more distal location after 15 years. Stem subsidence was >5 mm in 6 hips (9.1%), but secondary stability was achieved in all stems. Osseointegration was observed in 63 (95.5%) hips. Stem survivorship was 91.1% with an end point of any re-revision and 94.6% for aseptic re-revision.ConclusionA tapered and fluted modular stem demonstrated excellent implant survivorship with reliable bony fixation at a mean follow-up of 16 years. This type of stem can be a durable option for revision THA in patients who have femoral defects.     

Minimum 5-Year Results in 96 Consecutive Hips Treated With a Tapered Titanium Stem System

We performed total hip arthroplasty with single titanium stem in 96 consecutive, nonselected hips. All patients, regardless of bone type and shape, neck shaft angulation, or age, received the same implant. Patients were followed for a minimum of 5 years, and an independent radiographer evaluated the hips for ingrowth, subsidence, leg-length discrepancy, and remodeling. The average Harris Hip score was 96 points (range, 73-100 points) at final follow-up. Radiographically, all stems were ingrown. No stem had more than 3 mm of subsidence, and there were no leg-length discrepancies more than 5 mm. We concluded that this titanium stem is a versatile option for total hip arthroplasty in patients with a wide variety of demographic and femur characteristics.     

Primary total hip arthroplasty with an uncemented femoral component: a long-term study of the Taperloc stem

The purpose of the current study was to evaluate the long-term result of a tapered, uncemented femoral component. We retrospectively reviewed the clinical and radiographic records of 121 patients (129 hips) who underwent primary total hip arthroplasty with the use of the Taperloc uncemented stem. Follow-up averaged 11 years (range, 6-15 years). The mean Harris Hip Score at the latest follow-up was 92.1. Thigh pain was reported in 5 patients (3.6%). One stem was revised at 6 years because of severe proximal femoral osteolysis. There was no evidence of radiographic subsidence or loosening around any stems. The overall medium- to long-term outcome of the Taperloc stem is excellent, with a low revision rate and high patient satisfaction.     

初次混合式全髋关节置换术骨水泥柄的生存率分析

目的 探讨骨水泥柄全髋关节置换术后中期临床疗效.方法 接受骨水泥柄髋关节置换患者148例167髋,男95例106髋,女53例61髋;年龄28~87岁,平均62.8岁;体重45.2~87.4 kg,平均57.2 kg;身高146~184cm,平均161.5cm;平均体重指数21.4.临床疗效以Harris评分为标准,根据影像学资料评估股骨柄假体位置、骨水泥壳、假体周围骨重塑和骨溶解发生情况.以股骨假体无菌性松动和任何原因所致的假体翻修为终点,对假体生存率采用Kaplan-Meier分析.结果 106例114髋获得随访,随访时间6.5~9.5年,平均8.1年.术前Harris评分8~54分,平均42分;末次随访时76~100分,平均94分.无一例发生无菌性松动及假体翻修.6髋假体柄平均下沉1.83mm.16髋(14%)股骨侧出现<1mm的影像学透亮线,9髋(8%)Gruen Ⅰ区和Ⅶ区出现局灶性骨溶解所致斑点样影像学透亮区.106髋(93%)股骨侧有不同程度的皮质变薄或皮质松质骨化,均位于Ⅶ区.假体生存率为100%(95%可信区间.0.95-1.00).结论 采用第三代骨水泥技术固定股骨柄,可取得较好中期临床效果,但仍存在骨溶解、股骨近端皮质骨吸收重塑等潜在问题.     

Management of Periprosthetic Femur Fractures Treated With Distal Fixation Using a Modular Femoral Stem Using an Anterolateral Approach

The authors retrospectively analyzed 27 hips with periprosthetic femoral fractures (types B2 and B3) treated with distal fixation using a modular, fluted, femoral stem. The average follow-up was 4.8 years. Most fractures (25 hips) were united (92.6%), and mean Harris Hip Score at follow-up was 84.7. Subsidence was noted in 2 patients within 6 months postoperatively, but despite the subsidence, one achieved union. One patient developed peroneal nerve palsy. Two hips were defined as failure: one nonunion associated with infection, and the other one had 10 mm more subsidence. No dislocation occurred in any of the patients. This technique has proven to be reliable in the treatment of difficult fractures in the acute stage, although concerns regarding the subsidence remain when using this femoral stem.     

Minimum 15-Year Results of a Dual-Offset Uncemented Femoral Stem in Total Hip Arthroplasty

BackgroundThe aim of the present study is to assess the long-term clinical and radiological outcomes of a proximal porous-coated, dual-offset, tapered titanium alloy uncemented stem at a minimum of 15 years of follow-up.MethodsWe reviewed 210 total hip arthroplasties (in 193 patients) performed between 1996 and 1999 and followed prospectively in our database who received the Synergy stem. We report a Kaplan-Meier survival analysis as well as the Harris Hip Score, the Western Ontario and McMaster University Arthritis Index, and the Short Form Health Survey-12 scores. Radiographs were evaluated for evidence of subsidence, osteolysis, osteointegration, or loosening.ResultsThe average follow-up was 16 years (range, 15-17.7 years). Kaplan-Meier survival analysis with revision of stem for aseptic mechanical loosening (1 stem) as the end point revealed a cumulative survival rate of 99.5% at 16 years. The Harris Hip Score, the Western Ontario and McMaster University Arthritis Index, and the Short Form Health Survey-12 physical scores were all significantly improved (P < .001) from the preoperative period to latest follow-up. Minor osteolysis was observed proximally in 14 hips (6.6%) with no osteolysis distal to the porous coating.ConclusionTo our knowledge, this study represents the largest series reporting the longest clinical follow-up of this third-generation, dual-offset, proximal ingrowth, tapered cementless stem. The Synergy stem design has achieved excellent clinical outcomes, predictable osteointegration, and outstanding survivorship of 99.5% at a minimum of 15 years follow-up, representing the standard for femoral stems at our institution.     

Total Hip Arthroplasty With Trochanteric Ostectomy for Patients With Angular Deformity of the Proximal Femur

BackgroundTotal hip arthroplasty (THA) of patients with a proximal femoral deformity is technically demanding. This deformity poses the risk of femoral fracture or perforation; stem malposition; and failed stem fixation. To insert a femoral stem in neutral position with a good fit, we removed the greater trochanter in case of a varus deformity, and the lesser trochanter in case of valgus deformity, while performing THA. We aimed to evaluate stem position, implant stability, clinical results, and radiological changes after THAs using this technique.MethodsFifteen patients (17 hips; 11 varus hips and 6 valgus hips) underwent cementless THA using the trochanteric osteotomy technique in one institution. We evaluated procedure-specific complications: intraoperative femoral fracture, stem malposition, weakness of the abductor power and limp. Modified Harris Hip Score, radiological changes, and the stability of stems were assessed at a mean of 7.1 years of follow-up (range 2.0-15.5).ResultsFemoral fracture occurred during the insertion of the stem in 4 hips. All stems were aligned in neutral position. At the latest follow-up, the mean power of the abductor was 4.3 (range 3-5). Eleven patients had slight limp and 4 patients had moderate limp. All stems had bone-ingrown stability and no stem was revised. The mean modified Harris Hip Score improved from 50 points at the preoperative evaluation to 81 points at the final follow-up.ConclusionThe trochanteric excision enabled neutral insertion of cementless stem in patients with varus/valgus deformity of the proximal femur, and THA using this technique rendered favorable results.     

Cement-within-cement stem exchange using the collarless polished double-taper stem

The clinical and radiographic outcomes of the cement-within-cement femoral stem exchange technique at revision hip arthroplasty were determined. Twenty-three revisions with a collarless polished double-taper stem design were prospectively monitored at up to 12 years. The most common indications for revision were recurrent dislocation and acetabular revision. Radiographic stem subsidence was measured by the Ein Bild Röentgen Analyse method. There was no stem re-revision and no radiographic loosening. Stem within cement subsidence, an intentional design feature of this stem, averaged 0.8 mm (range, 0-2 mm). The average subsidence was similar to that in primary hip arthroplasty. The excellent long-term results of cemented collarless polished taper stems for primary and revision hip arthroplasty can be extended even further by cement-within-cement exchange, which preserves the femur.     

Isolated Acetabular Revision Hip Arthroplasty with the Use of Uncemented Cup

We evaluated the clinical and radiological results of isolated acetabular revision hip arthroplasty. Forty-three hips underwent isolated acetabular revision with uncemented cup and were followed up for an average of 76 months. The monoblock femoral stems were used in 20 hips and modular femoral stems in 23 hips. The average Harris Hip Score improved to 87 at last follow-up from 57 preoperatively. All femoral stems maintained stable fixation with bone ingrowth and no subsidence at last follow-up. Five hips with the monoblock stem underwent rerevision due to loosening of cup with osteolysis. The isolated acetabular revision is encouraging, but in reflection of the results of the monoblock head, the visual inspection of the femoral head is not enough for evaluation of its surface status.     

Assessment of early migration and clinical evaluation of a cemented femoral stem

A 2-year follow-up study was conducted on 46 patients to assess Harris Hip Scores (HHS) and early distal migration of the femoral stem after total hip arthroplasty using a fully cemented femoral stem. The mean age was 73.4 years. The Fullfix stem (Mathys A.G., Bettlach, Switzerland) is characterised by a mat polished surface and a flange aimed to compress the cement during the insertion process. Early distal migration was determined in 36 patients using the computer assisted EBRA-FCA method (Einzel-Bild-Roentgen-Analyse femoral component analysis). At 2 years, subsidence reached a mean value of 0.44 mm (95% CI: 0.19, 0.70), whereafter the stem appeared stable, i.e. distal migration reached a plateau. Females showed significantly higher migration than males (p < 0.01). EBRA-FCA proved to be an accurate method to measure early migration, with a standard deviation below 1 mm (0.56 mm in the interval 1-2 years). Harris Hip Scores (HHS) at 2 years follow-up averaged 89.6 (95% CI: 79.5, 99.8). As expected considering the small extent of migration, there was no correlation between subsidence and HHS (p = 0.5).     

Comparison of collared and collarless femoral components in primary uncemented total hip arthroplasty

Two hundred three consecutive primary uncemented total hip arthroplasties were prospectively randomized using collared and collarless versions of an identical titanium stem. Identical 28-mm titanium heads were implanted in all cases. One hundred three collared hips were compared with 100 collarless hips. Follow-up periods avereraged 45.7 months in both groups. Intraoperative, early, and late complications were similar. Hip scores, including thigh pain, at final follow-up visit were also similar. No significant differences were noted in acetabular or femoral radiolucencies, subsidence, osteolysis, or proximal femoral remodeling. At 5 years, more collarless stems revealed pedestal formation (57.1% vs 33.9%). The presence of a collar had no effect on the adequacy of fixation, proximal femoral osteopenia, or clinical scores at 5 years.