Aims

The purpose of this study is to report our updated results at a minimum follow-up of 30 years using a first generation uncemented tapered femoral component in primary total hip arthroplasty (THA).

In 80 patients with a mean age of 50 years, 97 uncemented primary THAs were performed using a titanium stem with a proximal circumferential plasma spray coating. Three different acetabular components were used, in 70% of cases a threaded and partly porous-coated design. At a mean follow-up of 8 years, two femoral components had been revised. One stem was revised 103 months after insertion owing to a comminuted fracture of the proximal femur, and one 104 months after insertion owing to deep infection. There were no stem revisions for aseptic loosening. We calculate the probability of survival of the femoral component at 0.98%. Sixteen acetabular components (14 threaded cups) had been revised in 13 patients. One femur had areas of distal osteolysis, associated with verified deep infection, but no signs of proximal loosening. Three femora had areas of minor proximal osteolysis. The mean Harris hip score at the latest follow-up was 91 points. We conclude that an uncemented titanium femoral component with a proximal circumferential plasma spray coating is an excellent option in THA in the young patient. As reported previously, aseptic loosening of threaded acetabular components was common

Introduction

The ideal method of fixation for femoral components in total hip arthroplasty (THA) is unknown. While good results have been reported for cemented and uncemented components, there is relatively little published prospective data with twenty years or more of follow up.

Results of the Furlong femoral component have been presented at an average of 17 years follow up. We have extended this follow up period to an average of 22.5 years with a minimum of 22 years and a maximum of 25 years.

Aims. We present the clinical and radiological results at a minimum follow-up of 20 years using a second-generation uncemented total hip arthroplasty (THA). These results are compared to our previously published results using a first-generation hip arthroplasty followed for 20 years. Methods. A total of 62 uncemented THAs in 60 patients were performed between 1993 and 1994. The titanium femoral component used in all cases was a Taperloc with a reduced distal stem. The acetabular component was a fully porous coated threaded hemispheric titanium shell (T-Tap ST). The outcome of every femoral and acetabular component with regard to retention or revision was determined for all 62 THAs. Complete clinical follow-up at a minimum of 20 years was obtained on every living patient. Radiological follow-up was obtained on all but one. Results. Two femoral components (3.2%) required revision. One stem was revised secondary to a periprosthetic fracture one year postoperatively and one was revised for late sepsis. No femoral component was revised for aseptic loosening. Six acetabular components had required revision, five for aseptic loosening. One additional acetabular component was revised for sepsis. Radiologically, all femoral components remained well fixed. One acetabular was judged loose by radiological criteria. The mean Harris Hip Score improved from 46 points (30 to 67) preoperatively to 89 points (78 to 100) at final follow-up. With revision for aseptic loosening as the endpoint, survival of the acetabular component was 95% (95% confidence interval (CI) 90 to 98) at 25 years. Femoral component survival was 100%. Conclusion. The most significant finding of this report was the low prevalence of aseptic loosening and revision of the femoral component at a mean follow-up of 22 years. A second important finding was the survival of over 90% of the hemispheric threaded ring acetabular components. While these shells remain controversial, in this series they performed well. Cite this article: Bone Jt Open 2021;2(1):33–39

Introduction: The purpose of this study is to evaluate the clinical and radiogra phic outcome of patients with secondary osteoarthritis of the hip, who underwent custom-made cementless THA. Methods: Between January 1994 and June 1997, 98 prim ary cementless custom-made THA’s were performed in 76 patients with secondary osteoarthritis and reviewed at mean 6 years follow-up (range: 4 – 7.5 years). Nine patients had a previous femoral osteotomy. There were 69 females and seven males. The mean age at operation was 54 years (40 – 73 years). Custom-made, 125 mm-long, titanium femoral components with blasted surface were fabricated based on the computerized tomography. Results: The mean Harris Hip Score improved from 43 to 95 points. 97 patients (99%) had more than 80 points for total score, and 2 patients (2%) had thigh pain at the latest follow-up. Radiographically, 86 hips (87%) showed obviously extensive bone ongrowth onto the middle part of the stem while 8 hips (9%) showed stable fibrous fixation. Four hips (4%) were unstable: more than 2 mm subsidence in 2 hips and more than 2 degrees varus migration in 2 hips. Of these 4 hips, 2 had intraoperative cracks of the poximal femur and 2 had varus positioning of the stem. Discussion and conclusion: Cementless THA has been advocated to enhance fit and fill of variable hip geometry. However, some clinical studies failed to show that custom implants significantly improve clinical success or implant longevity because their surface finish was not optimal. Custom-made titanium femoral components with blasted surface showed good clinical results. The reasons for radiolographical failures were because of intraoperative technical errors and these might be derived from 125 mm-long stem with maximum canal fill. A shorter stem may be an option because it may improve the feasibility of stem insertion and the distal fill

Revision of the total hip femoral component in the presence of significant bone loss requires a variety of implants as well as fixation devices and bone substitute materials. Rule 1: Fix the implant into the best remaining bone. A variety of stem shapes and sizes are needed to fill the bone cylinder. Stem modularity is helpful to fashion a good fit, but every taper junction is a liability as a potential source of metal debris and a weak spot in the stem. Rather, fully porous-coated titanium femoral components with a tapered stem design are safe, convenient, and reasonably inexpensive. Rule 2: Reconstruct the bone to accept a rigidly fixed intramedullary stem. Cables, strut allograft, plates, and screws are needed to support the remaining bone. Rule 3: Manage the bone so that it is still viable after the implant is inserted. As much intraosseous and extraosseous blood supply as possible should be maintained, so broaching rather than extensive reaming is the best choice for maintaining bone viability. Rarely more exotic procedures such as reduction osteotomy must be done to achieve rigid fixation of implants

Revision total hip replacement may be technically challenging, with component selection being one of the challenges. Modular titanium femoral components have some advantages, and our aim was to assess the medium term outcome of the use of such a component [Revitan or PFM]. We reviewed 323 patients undergoing revision with one of these femoral stems. We applied the Oxford Hip Score, the Charnley Class, and the Devane Patient Activity Level to each patient. The average follow up time was 6.58 years. The mean Oxford score was 35.74.39.8% of the patients were Charnley Class B. 52.4% of patients had an activity score indicating a moderate level of activity ie they could participate in gardening, swimming and other leisure pursuits. The overall outcome was good with this prosthesis. The Oxford scores were comparable with the national mean for revision THR on the NZ National Joint Register

Introduction: Since 1992 over 3000 custom-made cemented titanium femoral components have been implanted during total hip replacement in our centre. Stems are machined using CAD-CAM. Measurements are made from screened AP and lateral x-rays of known magnification. Normal joint centre is recreated by controlling offset and vertical height of the femoral component. Method: Joint centre and limb length were analysed radiologically in consecutive 100 patients following total hip replacement for unilateral arthritis. Joint centre was defined relative to the pelvis and femur. The anatomical axis and offset of the femur were defined using a screened x-ray of known magnification taken to show maximum offset. Femoral centre height was defined relative to the greater trochanter. Results: In general, acetabular joint centre was placed medial and high, tending to reduce limb length slightly. Conversely, on the femoral side the tendency was to leave the component proud, producing an increase in limb length. Most patients had limb length restored to within 6mm of normal. This study confirms the effectiveness of the Belfast Custom Stem in restoring joint centre and limb length

Introduction and Aims: With interest in minimally invasive surgery, and smaller incisions for total hip arthroplasty (THA), ways to ensure appropriate alignment are critical. Femoral stem varus has been associated with poorer results. We report the incidence of varus placement of a tapered, proximally plasma-sprayed, titanium femoral component and describe the outcomes of varus at minimum five-year follow-up. Method: Between 1986 and 1997, 1080 tapered, proximally plasma-sprayed femoral components were implanted in primary cementless THA at one institution. Twenty-six components in 25 patients were placed in five degrees or more of varus. Two patients were lost to follow-up. The need for further surgery was assessed and Harris hip scores evaluated. Results: Harris hip scores improved an average of 44 points. All femoral components were judged to be osteo-integrated. There was no displacement or progression into further varus, or impending failures. One well-fixed stem was revised at an outside institution for unexplained pain at 2.5 years. Survival with aseptic loosening as an end-point is 100 percent. Overall survival of the femoral component is 96 percent at 10 years average follow-up. Conclusion: As visualisation decreases with decreasing incision length, a component that is reliably placed into appropriate position is required. Implant position with this component is forgiving. It may be an excellent choice for less-invasive techniques with compromised visualisation. In varus, the stem performs well, with no revisions for aseptic loosening and a 96 percent survival at up to 16 years

Introduction and Aims: The standard treatment for an infected total hip replacement involves removal of all foreign material and re-implantation in either one or two stages with antibiotic cement. This study has investigated the use of cementless reconstruction in infected hip arthroplasties to determine if there is a difference in the re-infection rate. Method: Thirteen patients (three females and 10 males) with an average age of 67 have been followed-up prospectively after revision hip surgery for infection. Removal of the prosthesis was followed by six weeks intravenous antibiotics and in some cases a period of oral therapy. Reconstruction was undertaken at a median of four months post Girdlestone’s arthroplasty, with the exception of a one-stage exchange for medical reasons. Cementless titanium femoral components were used in all revisions and titanium acetabular components where applicable. Allograft and cage reconstruction were employed for major pelvic defects. Results: Patients have been followed-up for an average of 58 months (range 12–96 months), with no loss to follow-up. Bacteria were cultured from eleven (11) of the thirteen (13) patients and the other two were clinically septic. Bacteria cultured included MRSA, Staph. Aureus, E.Coli and Strep. Faecalis. All prostheses remain in situ with improvement in both Charnley and Oxford hip scores. No recurrence of infection has been documented clinically or radiologically and no component is loose. Conclusion: Debate still exists about the merits of one vs. two-stage reconstruction for infected hip arthroplasty. This series with mid-term follow-up demonstrates that cementless reconstruction for infected hip arthroplasty is successful in providing an infection-free stable revision

Purpose: The purpose of our study was to compare serum titanium levels in patients with the three-piece modular AcuMatch® and one-piece nonmodular Versys® titanium femoral components. Methods: Blood samples were obtained at multiple time points for four years after the surgery in patients with the Versys® one-piece (47 patients) or AcuMatch® three-piece (70 patients) femoral stems. Control levels were measured in 20 patients without titanium implants. Titanium (Ti) levels were measured using high resolution inductively coupled-plasma mass spectroscopy by a technician blinded to the patient groups. Results: Medium Ti was significantly lower in the control group (.21 & #61549;g/L), when compared to patients with one- and three-part stems at all follow-up periods (p < .02). At 1 and 2 years post-operatively, medium Ti levels in the three-part group (3.1 and 3.4 & #61549;g/L) were significantly higher than levels in the one-part group (1.7 and 1.6 & #61549;g/L) (p < .004). At 3 and 4 years, medium titanium levels were not significantly different in the one-part group (2.5 and 2.7 & #61549;g/L) when compared to the three-part group (3.5 and 3.1 & #61549;g/L) (p > .05). Conclusions: The intraoperative flexibility provided by modular femoral stems may be offset by increased wear at modular junctions. Ti levels were significantly higher in patients with a highly modular three-part femoral stems at 1 and 2 years but no significant difference was found at 3 and 4 years postoperatively. Continued monitoring of these patients is warranted to determine if metal levels can be used to evaluate stem performance

Historically we know that all femoral, cemented stems have not performed the same. The Muller stem with its sharp comers did not perform as well as the Charnley femoral component. Titanium femoral components have not performed as well in the cemented situation as have stiffer chrome cobalt components. Today we have come to recognise that the durability of a cemented femoral component is dependent on a number of variables to include stem geometry and surface finish as well as the cement technique. Since several designs including the Trapezoidal-28, the Exeter, and the Iowa have incorporated various surface finishes over time, the issue of surface finish is one that some investigators think is relatively important. Components with rougher surface finishes adhere better to cement, decrease cement strains, and when they become loose are more likely to abrade cement. Components with smooth surface finishes do not adhere to cement, place cement under compression and when they become loose they are less likely to abrade cement. When these three stems were evaluated with both smooth and matte finishes the smooth surface finish stems have always demonstrated better results with less loosening and less osteolysis. However some matte finish designs have performed well including the CAD and the HD-2. Whatever prosthesis is utilised all investigators agree that it is optimal to have the prosthesis surrounded by cement, hence the use of centralisers. Hence today all would agree that the surgeon should use a torsionally sound stem and place an adequate cement mantle around that stem at the time of surgery .If that can be achieved all stems may be equal, however if cement mantle defects are inevitable a smooth surface finish probably has better durability

Sixty-two consecutive primary total hip arthroplasties were prospectively randomized to receive either hydroxyapatite coated (thirty-five hips) or nonhydroxy-apatite coated (twenty-seven hips) femoral prostheses. At a minimum eleven-year followup fifty-one hips (forty-four patients) were evaluated. Only one femoral stem had been revised (secondary to traumatic periprosthetic fracture). Radiographs were available for thirty-nine hips. None of these femoral stems were loose. Harris Hip scores were evaluated for thirty-six unrevised hips and did not differ significantly between the two groups. There appears to be no significant advantage to hydroxyapatite coating for this femoral prosthesis at an average follow-up of thirteen years. There are a paucity of long term randomized controlled trials on results of hydroxapatite coating of femoral prostheses. The purpose of this study was to update the results of a prospective randomized study of a proximally pourous coated, tapered titanium femoral component with and without hydroxyapatite coating. Sixty-two consecutive primary total hip arthroplasties done by one surgeon in fifty-five patients were prospectively randomized to receive either hydroxyapatite coated (thirty-five hips) or nonhydroxyapatite coated (twenty-seven hips) femoral prostheses. At a minimum eleven year followup, three hips (three patients) were lost to followup, and a further eight patients had expired (eight hips). The remaining surviving cohort of fifty-one hips (forty-four patients) were evaluated clinically, including Harris Hip Scores, and radiographically. At an average of thirteen years followup, only one femoral stem had been revised (secondary to traumatic periprosthetic fracture), that being in the hydroxyapatite group. There were eight acetabular revisions in the hydroxyapatite group (thirty-four percent) and four acetabular revisions in the nonhydroxyapatite group (sixteen percent). Radiographs were available for thirty-nine hips. None of these femoral stems were loose. Harris Hip scores were evaluated for thirty-six unrevised hips and did not differ significantly between the two groups. Using endpoints of femoral revision, radiographic loosening, and Harris Hip Scores there appears to be no significant advantage to hydroxyapatite coating for this femoral prosthesis at an average follow-up of thirteen years. Funding: Biomet, Warsaw IN