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Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_6 | Pages 20 - 20
1 May 2019
Lamb J King S van Duren B West R Pandit H
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Background. Method of fixation in THA is a contentious issue, with proponents of either technique citing improved implant survival and outcomes. Current comparisons rely on insufficiently powered studies with short-term follow up or larger poorly controlled registry studies. Patient factors are considered a key variable contributing to the risk of implant failure. One way to overcome this confounder is to compare the survival of cementless and cemented THAs patients who have undergone bilateral THAs with cemented hip on one side and cementless hip on the other. We compared stem survival of patients who have bilateral THA with one cemented stem in one hip and a cementless stem in the contralateral hip in the National Joint Registry. Methods. UK National Joint Registry is the largest registry of its kind in the world. This study included 2934 patients with 5868 THAs who underwent bilateral THAs s between 2003 and 2016. These patients had undergone bilateral sequential THAs within 3 years of each other: cemented THA on one side and cementless on the other, Patients had identical pre-operative American Society of Anaesthesiologists group for both THAs and same indication for surgery. Implant survival was compared using Cox regression with an endpoint of stem revision. Results. Ten-year all-cause survival of cementless stems was lower than for cemented stems (p<0.001), as was survival to aseptic loosening revision (p<0.001). Similar trends were seen across all age groups including young and old patients. There was a non-significant trend towards superiority of cemented stems in survival until periprosthetic fracture, dislocation and infection. Conclusion. Comparison of cementless with cemented stems within patients is a novel method to compare the outcomes of orthopaedic implants. Survival was better for cemented stems including for younger patients and aseptic loosening


Bone & Joint Open
Vol. 5, Issue 4 | Pages 286 - 293
9 Apr 2024
Upadhyay PK Kumar V Mirza SB Shah N

Aims

This study reports the results of 38 total hip arthroplasties (THAs) in 33 patients aged less than 50 years, using the JRI Furlong hydroxyapatite ceramic (HAC)-coated femoral component.

Methods

We describe the survival, radiological, and functional outcomes of 33 patients (38 THAs) at a mean follow-up of 27 years (25 to 32) between 1988 and 2018.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_6 | Pages 22 - 22
1 May 2019
Takada R Whitehouse S Hubble M Wilson M Howell J Timperley A Kassam A
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Introduction

Varus alignment of the femoral component in total hip arthroplasty (THA) is thought to be a risk factor for implant loosening and early revision surgery. The purpose of this study was to evaluate whether the Exeter stem tolerates varus alignment and assess if this theoretical malalignment has an influence on clinical outcomes.

Methods

A total of 4126 consecutive THAs were reviewed for patients between 2006 and 2012 to allow for a minimum five-year follow-up. To determine the effects of the stem alignment on results, the hips were classified into 3 groups on the basis of stem alignment in initial postoperative anteroposterior radiographs. The alignment of the stem was defined as neutral, valgus (≥ 3° of lateral deviation), or varus (≥ 3° of medial deviation). The primary outcome was all cause revision with patient related outcomes assessed with Oxford hip score pre and post-operatively.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_12 | Pages 17 - 17
23 Jun 2023
Schreurs BW van Veghel MH van der Koelen RE Hannink G Rijnen WH
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Although data on uncemented short stems are available, studies on cemented short-stemmed THAs are limited. These cemented short stems may have inferior long-term outcomes and higher femoral component fracture rates. Hence, we examined the long-term follow-up of cemented short Exeter stems used in primary THA. Within the Exeter stem range, 7 stems have a stem length of 125 mm or less. These stems are often used in small patients, in young patients with a narrow femoral canal or patients with anatomical abnormalities. Based on our local database, we included 394 consecutive cemented stems used in primary THA (n=333 patients) with a stem length ≤125 mm implanted in our tertiary referral center between 1993 and December 2021. We used the Dutch Arthroplasty Registry (LROI) to complete and cross-check the data. Kaplan-Meier survival analyses were performed to determine 20-year survival rates with stem revision for any reason, for septic loosening, for aseptic loosening and for femoral component fracture as endpoints. The proportion of male patients was 21% (n=83). Median age at surgery was 42 years (interquartile range: 30–55). The main indication for primary THA was childhood hip diseases (51%). The 20-year stem survival rate of the short stem was 85.4% (95% CI: 73.9–92.0) for revision for any reason and 96.2% (95%CI: 90.5–98.5) for revision for septic loosening. No stems were revised for aseptic femoral loosening. However, there were 4 stem fractures at 6.6, 11.6, 16.5 and 18.2 years of follow-up. The stem survival with femoral component fracture as endpoint was 92.7% (CI: 78.5–97.6) at 20 years. Cemented short Exeter stems in primary THA show acceptable survival rates at long-term follow-up. Although femoral component fracture is a rare complication of a cemented short Exeter stem, orthopaedic surgeons should be aware of its incidence and possible risk factors


The Lubinus SP II is an anatomical femoral stem with high survivorship levels notably described in the Swedish Arthroplasty Register. As the clinical and economic burden of revision total hip arthroplasty (THA) and periprosthetic fracture (PPF) continues to increase, it has been suggested that use of anatomical stems may facilitate more uniform cement mantles and improve implant survival. The primary aim of this study was to determine the long-term survivorship and PPF rate of the Lubinus SP II 150mm stem in a single UK centre. Between January 2007 and April 2012, 1000 consecutive THAs were performed using the Lubinus SP II femoral stem in our institution. Patient demographics and operative details were collected in a prospective arthroplasty database. Patient records and national radiographic archives were then reviewed at a mean of 12.3 years (SD 1.3) following surgery to identify occurrence of subsequent revision surgery, dislocation or periprosthetic fracture. Mean patient age at surgery was 69.3 years (SD 10.1, 24–93 years). There were 634 women (63%). Osteoarthritis was the operative indication in 974 patients (97%). There were 13 revisions in total (4 for recurrent dislocation, 3 for infection, 6 for acetabular loosening) and 16 dislocations (1.6%). Stem survivorship at 10 years was 99.6% (95 % confidence interval [CI], 99.5%–99.7%) and at 15 years was 98.8% (98.7%–98.9%). The 15-year stem survival for aseptic loosening was 100%. Analysis of all cause THA failure demonstrated a survivorship of 99.1% (99.0%–99.3%) at 10 years and 98.2% (98.1%–98.3%) at 15 years. There were 4 periprosthetic fractures in total (0.4%) at mean 12.3 year follow-up. The Lubinus SP II stem demonstrated excellent survivorship, low dislocation rates and negligible PPF rates up to 15 years following primary THA. Use of anatomical stems such as the Lubinus SPII would appear to be a wise clinical and economic investment for patients and healthcare systems alike


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_14 | Pages 19 - 19
1 Nov 2021
Schreurs B Kuijpers M van Steenbergen L Hannink G
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The increasing number of total hip arthroplasty (THA) used in young patients will inevitably lead to more revision procedures at younger ages, especially since the outcome of primary THA in young patients is already inferior compared to older patients. However, these data are lacking in literature. The aim of this study was to determine the survival of both acetabular and femoral components placed during primary and revision hip arthroplasty in patients under 55 years using Dutch Arthroplasty Register (LROI) data. All primary THA registered in the LROI between 2007–2018 in patients under 55 years were selected (n=25,682). Subsequent cup- and stem revision procedures were included. Kaplan-Meier survival analyses were used to estimate the survival probability of primary and revised cup- and stem components. Mean follow-up of primary cups and stems was 5.8 years (SD 3.2) and 5.9 years (SD 3.2), respectively. In total, 659 cup revision procedures and 532 stem revision procedures were registered. Most common reason for cup revision was acetabular loosening (n=163), most common reason for stem revision was femoral loosening (n=202). Primary cup survival for any reason at 10 years follow-up was 96.1% (95%CI: 95.7–96.4). For primary stems, 10 year survival for any reason was 97.1% (95%CI: 96.7–97.3). Mean follow-up of all revision procedures was 4.1 years (SD 2.9). Out of 659 cup revisions, 113 cup re-revisions were registered. Survival of revised cups, with end-point cup re-revision for any reason was 82.2% (95%CI: 78.8–85.1) at 5 years follow-up. Out of 532 stem revisions, 89 stem re-revisions were registered. For revised stems, survival at 5 year follow-up, with endpoint stem re-revision for any reason was 82.0% (95%CI: 78.2–85.2). The outcome of revised acetabular and femoral components is worrisome, with a survival of 82% at 5 years follow-up. This information is valuable to provide realistic expectations for these young patients at time of primary THA


The Bone & Joint Journal
Vol. 101-B, Issue 10 | Pages 1199 - 1208
1 Oct 2019
Lamb JN Matharu GS Redmond A Judge A West RM Pandit HG

Aims. We compared implant and patient survival following intraoperative periprosthetic femoral fractures (IOPFFs) during primary total hip arthroplasty (THA) with matched controls. Patients and Methods. This retrospective cohort study compared 4831 hips with IOPFF and 48 154 propensity score matched primary THAs without IOPFF implanted between 2004 and 2016, which had been recorded on a national joint registry. Implant and patient survival rates were compared between groups using Cox regression. Results. Ten-year stem survival was worse in the IOPFF group (p < 0.001). Risk of revision for aseptic loosening increased 7.2-fold following shaft fracture and almost 2.8-fold after trochanteric fracture (p < 0.001). Risk of periprosthetic fracture of the femur revision increased 4.3-fold following calcar-crack and 3.6-fold after trochanteric fracture (p < 0.01). Risk of instability revision was 3.6-fold after trochanteric fracture and 2.4-fold after calcar crack (p < 0.001). Risk of 90-day mortality following IOPFF without revision was 1.7-fold and 4.0-fold after IOPFF with early revision surgery versus uncomplicated THA (p < 0.001). Conclusion. IOPFF increases risk of stem revision and mortality up to ten years following surgery. The risk of revision depends on IOPFF subtype and mortality risk increases with subsequent revision surgery. Surgeons should carefully diagnose and treat IOPFF to minimize fracture progression and implant failure. Cite this article: Bone Joint J 2019;101-B:1199–1208


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_6 | Pages 36 - 36
1 May 2019
Syed F Magra M Saunders P Ugwuoke A Young S
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Introduction. Primary fixation in uncemented Total Hip Replacement (THR) is achieved by implanting an appropriately sized stem. Last year, in our pilot study, we classified undersizing & reported the incidence of subsidence & radiolucent lines (RLL) in undersized uncemented stems. Now we report on a larger cohort of patients, reporting undersizing and its association with radiolucent lines and subsidence. Secondarily we report on the effect of using a collar, patients' BMI, and in a smaller group the five-year failure rate. Methods. A retrospective review of electronic records of 1337 cases who underwent THR using the Corail stem was carried out. 1204 (Collared 1042, Uncollared 162) had a minimum follow up of 1 year, 693 of those had a follow up of at least 5 years. Radiological review was carried out by 2 independent investigators. Results. 19.77% stems were undersized. There was significantly higher incidence of subsidence & RLL in undersized stems with more than 1 year follow up. There no significant increase in incidence of RLL in those with BMI greater than 30 (16.88% vs 18.81%). Analysis of undersized collared stems demonstrated that even in this sub group undersizing is associated with increased incidence of RLL (P 0.00001) & subsidence (P 0.0003). A five year follow up, the revision rate for aseptic loosening of stem was 3.09% in undersized stems & 0.29% in appropriately sized stems (P 0.06). Conclusions. Our study indicates undersizing of uncemented stems is associated with poorer radiological outcomes & there's a trend of higher revision rate at 5 year follow up. This reinforces the importance of implanting appropriately sized stem, as undersizing can potentially compromise stem survival in uncemented total hip arthroplasty


Bone & Joint Open
Vol. 4, Issue 7 | Pages 507 - 515
6 Jul 2023
Jørgensen PB Jakobsen SS Vainorius D Homilius M Hansen TB Stilling M

Aims

The Exeter short stem was designed for patients with Dorr type A femora and short-term results are promising. The aim of this study was to evaluate the minimum five-year stem migration pattern of Exeter short stems in comparison with Exeter standard stems.

Methods

In this case-control study, 25 patients (22 female) at mean age of 78 years (70 to 89) received cemented Exeter short stem (case group). Cases were selected based on Dorr type A femora and matched first by Dorr type A and then age to a control cohort of 21 patients (11 female) at mean age of 74 years (70 to 89) who received with cemented Exeter standard stems (control group). Preoperatively, all patients had primary hip osteoarthritis and no osteoporosis as confirmed by dual X-ray absorptiometry scanning. Patients were followed with radiostereometry for evaluation of stem migration (primary endpoint), evaluation of cement quality, and Oxford Hip Score. Measurements were taken preoperatively, and at three, 12, and 24 months and a minimum five-year follow-up.


The Bone & Joint Journal
Vol. 104-B, Issue 9 | Pages 1039 - 1046
1 Sep 2022
Özdemir E Kuijpers MFL Visser J Schreurs BW Rijnen WHC

Aims

The aim of this study is to report the long-term outcomes of instrumented femoral revisions with impaction allograft bone grafting (IBG) using the X-change femoral revision system at 30 years after introduction of the technique.

Methods

We updated the outcomes of our previous study, based on 208 consecutive revisions using IBG and the X-change femoral revision system in combination with a cemented polished stem, performed in our tertiary care institute between 1991 and 2007. Kaplan-Meier survival analyses were used to determine the survival rate of the revisions with endpoint revision for any reason and aseptic loosening. Secondary outcomes were radiological loosening and patient-reported outcome measures.


The Bone & Joint Journal
Vol. 104-B, Issue 6 | Pages 647 - 656
1 Jun 2022
Knudsen MB Thillemann JK Jørgensen PB Jakobsen SS Daugaard H Søballe K Stilling M

Aims

BoneMaster is a thin electrochemically applied hydroxyapatite (HA) coating for orthopaedic implants that is quickly resorbed during osseointegration. Early stabilization is a surrogacy marker of good survival of femoral stems. The hypothesis of this study was that a BoneMaster coating yields a fast early and lasting fixation of stems.

Methods

A total of 53 patients were randomized to be treated using Bi-Metric cementless femoral stems with either only a porous titanium plasma-sprayed coating (P group) or a porous titanium plasma-sprayed coating with an additional BoneMaster coating (PBM group). The patients were examined with radiostereometry until five years after surgery.


Bone & Joint Open
Vol. 2, Issue 12 | Pages 1035 - 1042
1 Dec 2021
Okowinski M Hjorth MH Mosegaard SB Jürgens-Lahnstein JH Storgaard Jakobsen S Hedevang Christensen P Kold S Stilling M

Aims

Femoral bone preparation using compaction technique has been shown to preserve bone and improve implant fixation in animal models. No long-term clinical outcomes are available. There are no significant long-term differences between compaction and broaching techniques for primary total hip arthroplasty (THA) in terms of migration, clinical, and radiological outcomes.

Methods

A total of 28 patients received one-stage bilateral primary THA with cementless femoral stems (56 hips). They were randomized to compaction on one femur and broaching on the contralateral femur. Overall, 13 patients were lost to the ten-year follow-up leaving 30 hips to be evaluated in terms of stem migration (using radiostereometry), radiological changes, Harris Hip Score, Oxford Hip Score, and complications.


The Bone & Joint Journal
Vol. 95-B, Issue 11_Supple_A | Pages 17 - 20
1 Nov 2013
Munro JT Masri BA Garbuz DS Duncan CP

Tapered, fluted, modular, titanium stems are increasingly popular in the operative management of Vancouver B2 and selected B3 peri-prosthetic femoral fractures. We have reviewed the results at our institution looking at stem survival and clinical outcomes and compared this with reported outcomes in the literature. Stem survival at a mean of 54 months was 96% in our series and 97% for combined published cases. Review of radiology showed maintenance or improvement of bone stock in 89% of cases with high rates of femoral union. Favourable clinical outcome scores have reported by several authors. No difference in survival or clinical scores was observed between B2 and B3 fractures. Tapered stems are a useful option in revision for femoral fracture across the spectrum of femoral bone deficiency. Cite this article: Bone Joint J 2013;95-B, Supple A:17–20


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 11_Supple_A | Pages 58 - 60
1 Nov 2012
Munro JT Garbuz DS Masri BA Duncan CP

Tapered, fluted, modular, titanium stems have a long history in Europe and are increasing in popularity in North America. We have reviewed the results at our institution looking at stem survival and clinical outcomes. Radiological outcomes and quality of life assessments have been performed and compared to cylindrical non-modular cobalt chromium stems. Survival at five years was 94%. This fell to 85% at ten years due to stem breakage with older designs. Review of radiology showed maintenance or improvement of bone stock in 87% of cases. Outcome scores were superior in tapered stems despite worse pre-operative femoral deficiency. Tapered stems have proved to be a useful alternative in revision total hip arthroplasty across the spectrum of femoral bone deficiency


Introduction. Analysis of registry data shows that few units achieve results better than 99·98% control limits. Implant selection is considered a predictor of outcome variation in joint replacement. We analysed the outcomes of a unit with statistically “better than expected” results and compared to all other units within the National Joint Registry for England, Wales, Northern Ireland and Isle of Man (NJR). We sought to determine whether improved implant survival following primary total hip replacement (THR) is a centre effect or mediated by implant selection. Methods. We identified 664,761 THRs in the NJR. The exposure was the unit in which the THR was implanted and the outcome all-cause revision. Net failure was estimated using Kaplan-Meier and adjusted analyses used flexible parametric survival analysis. Results. The crude 10-year revision rate for THRs was 1·7% (95% CI: 1·3, 2·3) in the exemplar centre and 2·9% (95% CI: 2·8, 3·0) elsewhere (log rank test P<0·001). Of 6,230 THRs performed in the exemplar centre, 99·9% used the same femoral stem. After restricting analyses to this stem, crude survival from other units was 2·3% (95% CI: 2·2, 2·4) (log-rank test p=0·05). Age and sex adjusted analyses, restricted to the same stem/cup combinations as the exemplar centre, show no demonstrable difference in restricted mean survival time between groups (p=0·28). Conclusion. These results suggest the “better than expected” performance of an exemplar centre can be replicated by adopting key treatment decisions, such as implant selection. These decisions are easier to replicate than technical skills or system factors. This is an important and easily applicable lesson for all branches of medicine highlighting the potential pre-eminence of decision making over technical expertise


The Bone & Joint Journal
Vol. 103-B, Issue 7 Supple B | Pages 129 - 134
1 Jul 2021
Ayekoloye CI Abu Qa'oud M Radi M Leon SA Kuzyk P Safir O Gross AE

Aims

Improvements in functional results and long-term survival are variable following conversion of hip fusion to total hip arthroplasty (THA) and complications are high. The aim of the study was to analyze the clinical and functional results in patients who underwent conversion of hip fusion to THA using a consistent technique and uncemented implants.

Methods

A total of 39 hip fusion conversions to THA were undertaken in 38 patients by a single surgeon employing a consistent surgical technique and uncemented implants. Parameters assessed included Harris Hip Score (HHS) for function, range of motion (ROM), leg length discrepancy (LLD), satisfaction, and use of walking aid. Radiographs were reviewed for loosening, subsidence, and heterotopic ossification (HO). Postoperative complications and implant survival were assessed.


The Bone & Joint Journal
Vol. 97-B, Issue 8 | Pages 1038 - 1045
1 Aug 2015
Solomon LB Costi K Kosuge D Cordier T McGee MA Howie DW

The outcome of 219 revision total hip arthroplasties (THAs) in 98 male and 121 female patients, using 137 long length and 82 standard length cemented collarless double-taper femoral stems in 211 patients, with a mean age of 72 years (30 to 90) and mean follow-up of six years (two to 18) have been described previously. We have extended the follow-up to a mean of 13 years (8 to 20) in this cohort of patients in which the pre-operative bone deficiency Paprosky grading was IIIA or worse in 79% and 73% of femurs with long and standard stems, respectively.

For the long stem revision group, survival to re-revision for aseptic loosening at 14 years was 97% (95% confidence interval (CI) 91 to 100) and in patients aged > 70 years, survival was 100%. Two patients (two revisions) were lost to follow-up and 86 patients with 88 revisions had died. Worst-case analysis for survival to re-revision for aseptic loosening at 14 years was 95% (95% CI 89 to 100) and 99% (95% CI 96 to 100) for patients aged > 70 years. One additional long stem was classified as loose radiographically but not revised.

For the standard stem revision group, survival to re-revision for aseptic loosening at 14 years was 91% (95% CI 83 to 99). No patients were lost to follow-up and 49 patients with 51 hips had died. No additional stems were classified as loose radiographically.

Femoral revision using a cemented collarless double-taper stem, particularly with a long length stem, and in patients aged > 70 years, continues to yield excellent results up to 20 years post-operatively, including in hips with considerable femoral metaphyseal bone loss.

Cite this article: Bone Joint J 2015;97-B:1038–45.


The Bone & Joint Journal
Vol. 96-B, Issue 4 | Pages 455 - 461
1 Apr 2014
Evola FR Evola G Graceffa A Sessa A Pavone V Costarella L Sessa G Avondo S

In 2012 we reviewed a consecutive series of 92 uncemented THRs performed between 1986 and 1991 at our institution using the CLS Spotorno stem, in order to assess clinical outcome and radiographic data at a minimum of 21 years. The series comprised 92 patients with a mean age at surgery of 59.6 years (39 to 77) (M:F 43;49).

At the time of this review, seven (7.6%) patients had died and two (2.2%) were lost to follow-up. The 23-year Kaplan–Meier survival rates were 91.5% (95% confidence intervals (CI) 85.4% to 97.6%; 55 hips at risk) and 80.3% (95% CI, 71.8% to 88.7%; 48 hips at risk) respectively, with revision of the femoral stem or of any component as endpoints. At the time of this review, 76 patients without stem revision were assessed clinically and radiologically (mean follow-up 24.0 years (21.5 to 26.5)). For the 76 unrevised hips the mean Harris hip score was 87.1 (65 to 97). Femoral osteolysis was detected in five hips (6.6%) only in Gruen zone 7. Undersized stems were at higher risk of revision owing to aseptic loosening (p = 0.0003). Patients implanted with the stem in a varus position were at higher risk of femoral cortical hypertrophy and thigh pain (p = 0.0006 and p = 0.0007, respectively).

In our study, survival, clinical outcome and radiographic data remained excellent in the third decade after implantation. Nonetheless, undersized stems were at higher risk of revision owing to aseptic loosening.

Cite this article: Bone Joint J 2014;96-B:455–61.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 1 | Pages 12 - 15
1 Jan 2005
Robertson A Lavalette D Morgan S Angus PD

We present the clinical and radiographic outcome of 68 consecutive primary total hip replacements performed in 54 patients under the age of 55 years using a hydroxyapatite-coated femoral component and threaded cup with a modular ceramic head (JRI-Furlong). We reviewed 62 (91%) hips at a median follow-up of 8.8 years (5 to 13.8) after implantation; six (9%) were lost to follow-up. At review there had been four (6%) revisions but only one for aseptic loosening (acetabulum). Radiographic review of the remaining hips did not identify any evidence of femoral or acetabular loosening. The median Harris and Merle d’Aubigné and Postel hip scores were 95.9 (42.7 to 100) and 17 (3 to 18) respectively. The JRI-Furlong hip gives promising functional and radiographic results in young patients in the medium term.


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 5 | Pages 577 - 582
1 May 2009
Duncan WW Hubble MJW Howell JR Whitehouse SL Timperley AJ Gie GA

The removal of well-fixed bone cement from the femoral canal during revision of a total hip replacement (THR) can be difficult and risks the loss of excessive bone stock and perforation or fracture of the femoral shaft. Retaining the cement mantle is attractive, yet the technique of cement-in-cement revision is not widely practised. We have used this procedure at our hospital since 1989. The stems were removed to gain a better exposure for acetabular revision, to alter version or leg length, or for component incompatibility.

We studied 136 hips in 134 patients and followed them up for a mean of eight years (5 to 15). A further revision was required in 35 hips (25.7%), for acetabular loosening in 26 (19.1%), sepsis in four, instability in three, femoral fracture in one and stem fracture in one. No femoral stem needed to be re-revised for aseptic loosening.

A cement-in-cement revision of the femoral stem is a reliable technique in the medium term. It also reduces the risk of perforation or fracture of the femoral shaft.