Revision total hip arthroplasty (THA) is challenging when there is severe loss of bone in the proximal femur. The purpose of this study was to evaluate the clinical and radiographic outcomes of revision THA in patients with severe proximal femoral bone loss treated with a fluted, tapered, modular femoral component. Between January 1998 and December 2004, 92 revision THAs were performed in 92 patients using a single fluted, tapered, modular femoral stem design. Pre-operative diagnoses included aseptic loosening, infection and peri-prosthetic fracture. Bone loss was categorised pre-operatively as Paprosky types III-IV, or Vancouver B3 in patients with a peri-prosthetic fracture. The mean clinical follow-up was 6.4 years (2 to 12). A total of 47 patients had peri-operative complications, 27 of whom required further surgery. However, most of these further operations involved retention of a well-fixed femoral stem, and 88/92 femoral components (97%) remained in situ. Of the four components requiring revision, three were revised for infection and were well fixed at the time of revision; only one (1%) was revised for aseptic loosening. The most common complications were post-operative instability (17 hips, 19%) and intra-operative femoral fracture during insertion of the stem (11 hips, 12%). Diaphyseal stress shielding was noted in 20 hips (22%). There were no fractures of the femoral component. At the final follow-up 78% of patients had minimal or no pain. . Revision THA in patients with extensive proximal femoral bone loss using the Link MP fluted, tapered, modular stem led to a high rate of osseointegration of the stem at mid-term follow-up. Cite this article: Bone Joint J 2015; 97-B:312–17

Aims. Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves modular cementless, tapered, revision femoral components in conjunction with distal interlocking screws. The aim of this study was to analyze the rate of reoperations and complications and union of the fracture, subsidence of the stem, mortality, and the clinical outcomes in these patients. Methods. A total of 46 femoral components in patients with Vancouver B3 fractures (23 with Paprosky type IIIA, 19 with type IIIB, and four with type IV defects) in 46 patients were revised with a transfemoral approach using a modular, tapered, cementless revision Revitan curved femoral component with distal cone-in-cone fixation and prospectively followed for a mean of 48.8 months (SD 23.9; 24 to 112). The mean age of the patients was 80.4 years (66 to 100). Additional distal interlocking was also used in 23 fractures in which distal cone-in-cone fixation in the isthmus was < 3 cm. Results. One patient (2.2%) died during the first postoperative year. After six months, 43 patients (93.5%) had osseous, and three had fibrous consolidation of the fracture and the bony flap, 42 (91.3%) had bony ingrowth and four had stable fibrous fixation of the stem. No patient had radiolucency around the interlocking screws and no screw broke. One patient had non-progressive subsidence and two had a dislocation. The mean Harris Hip Score increased from of 57.8 points (SD 7.9) three months postoperatively to 76.1 points (SD 10.7) 24 months postoperatively. Conclusion. The 2° tapered, fluted revision femoral component with distal cone-in-cone-fixation, combined with additional distal interlocking in patients with bony deficiency at the isthmus, led to reproducibly good results in patients with a Vancouver B3 fracture and Paprosky type IIIA, IIIB, and IV defects with regard to union of the fracture, subsidence or loosening of the stem, and clinical outcomes. Cite this article: Bone Joint J 2024;106-B(4):344–351

Aims. Although good clinical outcomes have been reported for monolithic tapered, fluted, titanium stems (TFTS), early results showed high rates of subsidence. Advances in stem design may mitigate these concerns. This study reports on the use of a current monolithic TFTS for a variety of indications. Methods. A multi-institutional retrospective study of all consecutive total hip arthroplasty (THA) and revision total hip arthroplasty (rTHA) patients who received the monolithic TFTS was conducted. Surgery was performed by eight fellowship-trained arthroplasty surgeons at four institutions. A total of 157 hips in 153 patients at a mean follow-up of 11.6 months (SD7.8) were included. Mean patient age at the time of surgery was 67.4 years (SD 13.3) and mean body mass index (BMI) was 28.9 kg/m. 2. (SD 6.5). Outcomes included intraoperative complications, one-year all-cause re-revisions, and subsidence at postoperative time intervals (two weeks, six weeks, six months, nine months, and one year). Results. There were eight intraoperative complications (4.9%), six of which were intraoperative fractures; none occurred during stem insertion. Six hips (3.7%) underwent re-revision within one year; only one procedure involved removal of the prosthesis due to infection. Mean total subsidence at latest follow-up was 1.64 mm (SD 2.47). Overall, 17 of 144 stems (11.8%) on which measurements could be performed had >5 mm of subsidence, and 3/144 (2.1%) had >10 mm of subsidence within one year. A univariate regression analysis found that additional subsidence after three months was minimal. A multivariate regression analysis found that subsidence was not significantly associated with periprosthetic fracture as an indication for surgery, the presence of an extended trochanteric osteotomy (ETO), Paprosky classification of femoral bone loss, stem length, or type of procedure performed (i.e. full revision vs conversion/primary). Conclusion. Advances in implant design, improved trials, a range of stem lengths and diameters, and high offset options mitigate concerns of early subsidence and dislocation with monolithic TFTS, making them a valuable option for femoral revision. Cite this article: Bone Joint J 2020;102-B(2):191–197

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

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

We report our experience of revision total hip replacement (THR) using the Revitan curved modular titanium fluted revision stem in patients with a full spectrum of proximal femoral defects. A total of 112 patients (116 revisions) with a mean age of 73.4 years (39 to 90) were included in the study. The mean follow-up was 7.5 years (5.3 to 9.1). A total of 12 patients (12 hips) died but their data were included in the survival analysis, and four patients (4 hips) were lost to follow-up. The clinical outcome, proximal bone regeneration and subsidence were assessed for 101 hips. The mean Harris Hip Score was 88.2 (45.8 to 100) after five years and there was an increase of the mean Barnett and Nordin-Score, a measure of the proximal bone regeneration, of 20.8 (-3.1 to 52.7). Five stems had to be revised (4.3%), three (2.9%) showed subsidence, five (4.3%) a dislocation and two of 85 aseptic revisions (2.3%) a periprosthetic infection. . At the latest follow-up, the survival with revision of the stem as the endpoint was 95.7% (95% confidence interval 91.9% to 99.4%) and with aseptic loosening as the endpoint, was 100%. Peri-prosthetic fractures were not observed. We report excellent results with respect to subsidence, the risk of fracture, and loosening after femoral revision using a modular curved revision stem with distal cone-in-cone fixation. A successful outcome depends on careful pre-operative planning and the use of a transfemoral approach when the anatomy is distorted or a fracture is imminent, or residual cement or a partially-secured existing stem cannot be removed. The shortest appropriate stem should, in our opinion, be used and secured with > 3 cm fixation at the femoral isthmus, and distal interlocking screws should be used for additional stability when this goal cannot be realised. Cite this article: Bone Joint J 2014;96-B:889–95

If a surgeon is faced with altered lesser trochanter anatomy when revising the femoral component in revision total hip replacement, a peri-prosthetic fracture, or Paprosky type IIIb or type IV femoral bone loss, a modular tapered stem offers the advantages of accurately controlling femoral version and length. The splines of the taper allow rotational control, and improve the fit in femoral canals with diaphyseal bone loss. In general, two centimetres of diaphyseal contact is all that is needed to gain stability with modular tapered stems. By allowing the proximal body trial to rotate on a well-fixed distal segment during trial reduction, appropriate anteversion can be obtained in order to improve intra-operative stability, and decrease the dislocation risk. However, modular stems should not be used for all femoral revisions, as implant fracture and corrosion at modular junctions can still occur.

Cite this article: Bone Joint J 2013;95-B, Supple A:95–7.

Aims. United Classification System (UCS) B2 and B3 periprosthetic fractures in total hip arthroplasties (THAs) have been commonly managed with modular tapered stems. No study has evaluated the use of monoblock fluted tapered titanium stems for this indication. This study aimed to evaluate the effects of a monoblock stems on implant survivorship, postoperative outcomes, radiological outcomes, and osseointegration following treatment of THA UCS B2 and B3 periprosthetic fractures. Methods. A retrospective review was conducted of all patients who underwent revision THA (rTHA) for periprosthetic UCS B2 and B3 periprosthetic fracture who received a single design monoblock fluted tapered titanium stem at two large, tertiary care, academic hospitals. A total of 72 patients met inclusion and exclusion criteria (68 UCS B2, and four UCS B3 fractures). Primary outcomes of interest were radiological stem subsidence (> 5 mm), radiological osseointegration, and fracture union. Sub-analysis was also done for 46 patients with minimum one-year follow-up. Results. For the total cohort, stem osseointegration, fracture union, and stem subsidence were 98.6%, 98.6%, and 6.9%, respectively, at latest follow-up (mean follow-up 27.0 months (SD 22.4)). For patients with minimum one-year of follow-up, stem osseointegration, fracture union, and stem subsidence were 97.8%, 97.8%, and 6.5%, respectively. Conclusion. Monoblock fluted stems can be an acceptable modality for the management of UCS B2 periprosthetic fractures in rTHAs due to high rates of stem osseointegration and survival, and the low rates of stem subsidence, and revision. Further research on the use of this stem for UCS B3 periprosthetic fractures is warranted to determine if the same conclusion can be made for this fracture pattern. Cite this article: Bone Jt Open 2023;4(8):551–558

We had previously reported on early outcomes on a new fluted, titanium, monobloc stem with a three degree taper that has been designed for challenging femoral reconstruction in the setting of extensive bone loss. The aim of this study was to report its mid-term clinical and radiographic outcomes. This is a retrospective review of prospectively collected data carried out at a single institution between Jan 2017 and Dec 2019. 85 femoral revisions were performed using a new tapered, fluted, titanium, monobloc (TFTM) revision stem. Complications, clinical and radiographic data were obtained from medical records and a locally maintained database. Clinical outcomes were assessed using the Oxford Hip Score (OHS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). All post-operative radiographs were analysed for subsidence, osteolysis and femoral cortical bone remodelling. Mean follow-up was 60 months (range 28–84 months). Subsidence of 1.2 mm was noted in one patient. No cases of clinically significant subsidence (10 mm) were observed. At final follow-up, a statistically significant improvement was noted in functional outcome scores. The mean OHS preoperatively and at final follow-up were 24 (SD 13) and 42 (SD15). p = 0.04 mean difference 18 (95% CI 15–22). The mean WOMAC scores preoperatively and at final follow-up were 62 (SD23) and 88 (SD7) respectively (p < 0.001, mean difference 26; 95% CI 21–34). No stem fractures were noted within the follow-up period. Two patients had revision of the stem's one for infection and another for persistent pain. Positive mid-term clinical and radiological outcomes have been observed with this tapered, fluted, titanium, monobloc stem. Based on these results, this implant may be considered as a viable option in the majority of uncemented femoral revisions

Aims. The risk of mechanical failure of modular revision hip stems is frequently mentioned in the literature, but little is currently known about the actual clinical failure rates of this type of prosthesis. The current retrospective long-term analysis examines the distal and modular failure patterns of the Prevision hip stem from 18 years of clinical use. A design improvement of the modular taper was introduced in 2008, and the data could also be used to compare the original and the current design of the modular connection. Methods. We performed an analysis of the Prevision modular hip stem using the manufacturer’s vigilance database and investigated different mechanical failure patterns of the hip stem from January 2004 to December 2022. Results. Two mechanical failure patterns were identified: fractures in the area of the distal fluted profile (distal stem fracture) and failure of the modular taper (modular fracture). A failure rate of 0.07% was observed for distal stem fracture, and modular fracture rates of 1.74% for the original and 0.013% for the current taper design. Conclusion. A low risk of mechanical failure for both fracture types was observed compared to other known complications in revision hip arthroplasty. In addition, the data show that a design change did significantly reduce the risk of a modular fracture. Cite this article: Bone Joint J 2024;106-B(2):151–157

There is a paucity of long-term data on modular fluted tapered (MFT) stems for two-stage reimplantation following periprosthetic joint infection (PJI). The purpose of this study was to evaluate implant survivorship, radiographic results, and clinical outcomes in a large cohort of reimplantation THAs using MFT stems. We identified 236 reimplantation THAs from a single tertiary care academic institution from 2000 to 2020. Two designs of MFT stems were used as part of an established two-stage exchange protocol for the treatment of PJI. Mean age at reimplantation was 65 years, mean BMI was 32 kg/m. 2. , and 46% were female. Median stem diameter was 19 mm, and median stem length was 195 mm. Mean follow-up was 7 years. A competing risk model accounting for death was utilized. The 15-year cumulative incidence of any revision was 24%. There were 48 revisions, with the most common reasons being dislocation (n=25) and PJI (n=16). The 15-year cumulative incidence of any reoperation was 28%. Only 13 revisions involved the fluted tapered portion of the component (FTC), for a 15-year cumulative incidence of any FTC revision of 8%. Only 2 FTCs were revised for aseptic loosening, resulting in a 15-year cumulative incidence of FTC revision for aseptic loosening of 1%. Stem subsidence >5 mm occurred in 2% of unrevised cases, and all stems were radiographically stable at most recent follow-up. Mean HHS was 77 at most recent follow-up. This series demonstrated that MFT stems were durable and reliable even in the setting of two-stage reimplantation for infection. While the incidence of aseptic loosening was very low, the incidence of any revision was 24% at 15 years, primarily caused by dislocation and recurrent PJI. Level of Evidence: IV

Local anatomical abnormalities vary in congenital hip disease patients. Authors often present early to mid-term total hip arthroplasty clinical outcomes using different techniques and implants randomly on patients with different types of the disease, making same conclusions difficult. We report long term outcomes (13 to 23 years) of the treatment of low and high dislocation cases (separately) with total hip arthroplasty using TM technology acetabular cups (Implex initially and then Zimmer) and short fluted conical (Zimmer) femoral stems. From 2000 to 2010, 418 congenital hip disease hip joints were treated in our department with total hip arthroplasty. According to Hartofilakidis et al's classification, 230 hips had dysplasia, 101 low dislocation, (group A) and 87 high dislocation (group B). Pre-operative and post-operative values, at regular intervals, of HHS, SF-12, WOMAC, OHS and HOOS were available for all patients. Patient, surgeon and implant related failures and complications were recorded for all patients. In all cases an attempt was made to restore hip center of rotation. In group A the average lengthening was 2.8 cm (range: 1 to 4.2) and in group B 5.7 cm (range: 4.2 to 11). In both groups, no hips were revised due to aseptic loosening of either the acetabular cup or the femoral stem. In group A, a cumulative success rate of 95.6% (95% confidence interval, 92.7% – 97.4%) and in group B a cumulative success rate of 94.8% (95% confidence interval, 92.6%–96.9%) was recorded, at 20 years, with revision for any reason as an end point. No s.s. differences were found between groups when mean values of HHS, SF-12, WOMAC and OKS were compared. Satisfactory long-term clinical outcomes can be achieved in treating different types of congenital hip disease when appropriate surgical techniques combined with “game changing” implants are used

We sought to determine the short to medium-term clinical and radiographic outcomes using a short stem in young adults with a proximal femoral deformity (PFD). We prospectively studied 31 patients (35 hips) with PFDs treated with an uncemented primary THA using a short stem with cervicometaphyseal fixation between 2011–2018. There were 19 male (23 hips) and 12 female (12 hips) patients, with a mean BMI of 26.7±4.1 kg/m. 2. Twelve cases had a previous surgical procedure, and six of them were failed childhood osteotomies. Mean age of the series was 44±12 years, mean follow-up was 81±27 months and no patients were lost to follow-up. PFDs were categorized according to a modified Berry´s classification. Average preoperative leg-length discrepancy (LLD) was −16.3 mm (−50 to 2). At a mean time of 81 months of follow-up, survival rate was 97% taking revision of the stem for any reason and 100% for aseptic loosening as endpoints. No additional femoral osteotomy was required in any case. Average surgical time was 66 minutes (45 to 100). There was a significant improvement in the mHHS score when comparing preoperative and postoperative values (47.3±10.6 vs. 92.3±3.7, p=0.0001). Postoperative LLD was in average 1 mm (−9 to 18) (p=0.0001). According to Engh's criteria, all stems were classified as stable without signs of loosening. Postoperative complications included 1 pulmonary embolism, 1 neurogenic sciatic pain, 1 transient sciatic nerve palsy that recovered completely after six months, and 2 acute periprosthetic joint infections. One patient suffered a Vancouver B2 periprosthetic femoral fracture 45 days after surgery and was revised with a modular distally fixed uncemented fluted stem. A type 2B short stem evidenced promising outcomes at short to medium-term follow up in young adult patients with PFDs, avoiding the need for corrective osteotomies and a revision stem

Subsidence remains a concern when utilizing modern tapered fluted titanium (TFT) femoral stems and may lead to leg length discrepancy, impingement, instability and failure to obtain stem osseointegration. This study aims to compare stem subsidence across three modern TFT stems. Our secondary aim was to investigate the influence of bicortical contact or ‘scratch fit’ on subsidence, as well as the role of intraoperative imaging in maximizing this bicortical contact and preventing stem subsidence. A retrospective review of 271 hip arthroplasties utilizing modern TFT stems in a single institution was performed. Three stem designs were included in the analysis: one monoblock TFT stem (n=91) and two modular TFT stems (Modular A [n=90]; Modular B [n=90]). Patient demographics, Paprosky femoral bone loss classification, bi-cortical contact, utilization of intra-operative imaging and stem subsidence (comparison of initial post-operative radiograph to the latest follow up radiograph - minimum three months) were recorded. There was no statistically significant difference in the amount of subsidence between the three stems (Monoblock: 2.33mm, Modular A: 3.43mm, Modular B: 3.02mm; p=0.191). There was no statistical difference in subsidence >5mm between stems (Monoblock: 9.9%, Modular A: 22.2%, Modular B: 16.7%). Subgroup analysis based on femoral bone loss grading showed no difference in subsidence between stems. Increased bicortical contact was strongly associated with reduced subsidence (p=0.004). Intra-operative imaging was used in 46.5% (126/271) of cases; this was not correlated with bicortical contact (p=0.673) or subsidence (p=0.521). Across all groups, only two stems were revised for subsidence (0.7%). All three modern TFT stems were highly successful and associated with low rates of subsidence, regardless of modular or monoblock design. Surgeons should select the stem that they feel is most clinically appropriate

For over a decade, modular titanium fluted tapered (TFT) stems have demonstrated excellent clinical success for femoral revision total hip arthroplasty (THA) surgery. The aim of this study was to report the short-term outcomes of a novel modern monoblock TFT stem used for revision and complex primary THA with a minimum of 2 years follow-up. We identified 126 patients who received a single monoblock TFT stem - 26 patients for complex THA (failed fracture fixation) and 100 patients for revision THA. The reasons for revision THA included 40 for previous prosthetic joint infection (PJI), 42 for aseptic loosening, 9 for trunnionosis, 9 for periprosthetic fractures. The Paprosky grading for femoral bone loss at the time of surgery and the measured subsidence of femoral stems at 3 months follow-up were determined. We evaluated the number and indications for re-operations. The mean time from surgery was 3.9 years (range 2.0 to 6.9 years). A paired t-test analysis showed significant improvement from pre-operative versus post-operative clinical outcome scores (p<0.001) for HHS (38.76 +/- 15.24vs. 83.42 +/- 15.38), WOMAC (45.6 ± 19.0 vs. 69.9 ± 21.3) and SF-12 Physical component (31.7 ± 8.1 vs. 37.8 ± 11.3) and SF-12 Mental component (48.2 ± 12.2 vs. 51.6 ± 12.5). The Paprosky grading for femoral bone loss was Grade 1 (3.9%), Grade 2 (35.7%), Grade 3A (47.6%), Grade 3B (11.1%) and Grade 4 (1.6%) cases. There were 18 re-operations (14.7%) with 13 for PJI (7 treated with implant retention, 6 treated with a two-staged revision), 4 for instability and one for acetabular aseptic loosening. There were no aseptic failures of the stem. This novel modern monoblock TFT stem provided reliable femoral fixation and has increasingly supplanted the use of modular TFT stems for complex primary and revision surgery in our institution

Aims. Femoral revision component subsidence has been identified as predicting early failure in revision hip surgery. This comparative cohort study assessed the potential risk factors of subsidence in two commonly used femoral implant designs. Methods. A comparative cohort study was undertaken, analyzing a consecutive series of patients following revision total hip arthroplasties using either a tapered-modular (TM) fluted titanium or a porous-coated cylindrical modular (PCM) titanium femoral component, between April 2006 and May 2018. Clinical and radiological assessment was compared for both treatment cohorts. Risk factors for subsidence were assessed and compared. Results. In total, 65 TM and 35 PCM cases were included. At mean follow-up of seven years (1 to 13), subsidence was noted in both cohorts during the initial three months postoperatively (p < 0.001) then implants stabilized. Subsidence noted in 58.7% (38/65 cases) of the TM cohort (mean 2.3 mm, SD 3.5 mm) compared to 48.8% (17/35) of PCM cohort (mean 1.9 mm, SD 2.6 mm; p = 0.344). Subsidence of PCM cohort were significantly associated with extended trochanteric osteotomy (ETO) (p < 0.041). Although the ETO was used less frequently in PCM stem cohort (7/35), subsidence was noted in 85% (6/7) of them. Significant improvement of the final mean Oxford Hip Score (OHS) was reported in both treatment groups (p < 0.001). Conclusion. Both modular TM and PCM revision femoral components subsided within the femur. TM implants subsided more frequently than PCM components if the femur was intact but with no difference in clinical outcomes. However, if an ETO is performed then a PCM component will subside significantly more and suggests the use of a TM implant may be advisable. Cite this article: Bone Joint J 2020;102-B(6):709–715

Periprosthetic fractures (PPF) of the femur following total hip arthroplasty represent a significant complication with a rising incidence. The commonest subtype is Vancouver B2 type, for which revision to a long uncemented tapered fluted stem is a widely accepted management. In this study we compare this procedure to the less commonly performed cement-in-cement revision. All patients undergoing surgical intervention for a Vancouver B2 femoral PPF in a cemented stem from 2008 – 2018 were identified. We collated patient age, gender, ASA score, BMI, operative time, blood transfusion requirement, change in haemoglobin (Hb) level, length of hospital stay and last Oxford Hip Score (OHS). Radiographic analysis was performed to assess time to fracture union and leg length discrepancy. Complications and survivorship of implant and patients were recorded. 43 uncemented and 29 cement-in-cement revisions were identified. There was no difference in patient demographics between groups. A significantly shorter operative time was found in the cement-in-cement group, but there was no difference in transfusion requirement, Hb change, or length of hospital stay. OHS was comparable between groups. A non-significant increase in overall complication rates was found in the revision uncemented group, with a significantly higher dislocation rate. Time of union was comparable and there were no non-unions in the cement-in-cement group. A greater degree of stem subsidence was found in the uncemented group. There was no difference in any revision surgery required in either group. Three patients in the uncemented group died in the perioperative period, compared to none in the cement-in-cement group. With appropriate patient selection, both cement-in-cement and long uncemented tapered stem revision represent appropriate treatment options for Vancouver B2 fractures

Tapered fluted titanium stems are increasingly used for femoral revision arthroplasty. They are available in modular and non-modular forms. Modularity has advantages when the bone loss is severe, the proximal femur is mis shapen or the surgeon is unfamiliar with the implant, but it introduces the risk of fracture of the stem at the junction between it and the proximal body segment. For that reason, and while awaiting intermediate-term results of more recently introduced designs of this junction, non-modularity has attracted attention, at least for straightforward revision cases. . We review the risks and causes of fracture of tapered titanium modular revision stems and present an argument in favour of the more selective use of modular designs. Cite this article: Bone Joint J 2016;98-B(1 Suppl A):50–3

Introduction. Undersizing of an uncemented femoral stem is a post-operative description of a radiograph with unclear clinical importance. It may not always translate into a suboptimal clinical outcome. Aim. To describe a novel classification system of undersizing in a fully hydroxyapatite coated femoral implant, assess if it could be reliably reported between observers, and describe a simple way to assess the degree of undersizing on an AP radiograph. Methods. A retrospective review of 1000 consecutive total hip arthroplasties was conducted. Two investigators reviewed post-operative radiographs independently for stem undersizing. The data was tested for inter and intra-observer agreement using the Kappa method. Results. Undersizing was classified as:. Varus - Stem in contact proximally with medial calcar, and distally with lateral cortex. Valgus - Stem in contact proximally with lateral cortex, and distally with medial cortex. Uniform - Continuous margin around the stem of at least one-half tip width of the stem throughout. Champagne flute - Distal stem fills the narrow diaphysis with insufficient bony contact at the wide metaphysis. If varus or valgus undersizing was present we described the formation of two triangles of excess cancellous space around the implant, each having overlapping apices signifying undersizing by at least two sizes. 32% of the stems were undersized with Kappa demonstrating very good (89%) to good (86%) inter and intra observer agreement respectively. 50% of undersized stems were uniformly undersized, 36% were varus, 6% valgus, and 8% were in a champagne fluted shaped femur. A higher percentage of the lateralised (KLA) stems were undersized compared to other neck configurations (40%). 54% of these were varus undersized and this increased the offset up to 2cm. Conclusion. We describe a classification system for undersizing in hip arthroplasty. KLA stems have an increased tendency to be undersized in varus, thereby increasing the overall offset

Revision total hip arthroplasty (THA) is projected to increase by 137% from the years 2005 to 2030. Reconstruction of the femur with massive bone loss can be a formidable undertaking. The goals of revision surgery are to create a stable construct, preserve bone and soft tissues, augment deficient host bone, improve function, provide a foundation for future surgery, and create a biomechanically restored hip. Options for treatment of the compromised femur include: resection arthroplasty, allograft prosthetic composite (APC), proximal femoral replacement, cementless fixation with a modular tapered fluted stem, and impaction grafting. The purpose of this article is to review the treatment options along with their associated outcomes in the more severe femoral defects (Paprosky types IIIb and IV) in revision THA.