We report the use of porous metal acetabular revision shells in the treatment of contained bone loss. The outcomes of 53 patients with ≤ 50% acetabular bleeding host bone contact were compared with a control group of 49 patients with > 50% to 85% bleeding host bone contact. All patients were treated with the same type of trabecular metal acetabular revision shell. The mean age at revision was 62.4 years (42 to 80) and the mean follow-up of both groups was 72.4 months (60 to 102). Clinical, radiological and functional outcomes were assessed. There were four (7.5%) mechanical failures in the ≤ 50% host bone contact group and no failures in the > 50% host bone contact group (p = 0.068). Out of both groups combined there were four infections (3.9%) and five recurrent dislocations (4.9%) with a stable acetabular component construct that were revised to a constrained liner. Given the complexity of the reconstructive challenge, porous metal revision acetabular shells show acceptable failure rates at five to ten years’ follow-up in the setting of significant contained bone defects. This favourable outcome might be due to the improved initial stability achieved by a high coefficient of friction between the acetabular implant and the host bone, and the high porosity, which affords good bone ingrowth.

Aims. Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects. Methods. We performed a retrospective review at a single institution of patients undergoing revision THA by a single surgeon. We identified 49 consecutive patients with large acetabular defects where the biphasic BGS was applied, with no other products added to the BGS. After placement of metallic acetabular implants, the BGS was injected into the remaining bone defects surrounding the new implants. Patients were followed and monitored for functional outcome scores, implant fixation, radiological graft site remodelling, and revision failures. Results. Mean follow-up was 39.5 months (36 to 71), with a significant improvement in post-revision function compared to preoperative function. Graft site remodelling was rated radiologically as moderate in 31 hips (63%) and strong in 12 hips (24%). There were no cases of complete graft site dissolution. No acetabular loosening was identified. None of the patients developed clinically significant heterotopic ossification. There were twelve reoperations: six patients developed post-revision infections, three experienced dislocations, two sustained periprosthetic femur fractures, and one subject had femoral component aseptic loosening. Conclusion. Our series reports bone defect restoration with the sole use of a biphasic injectable BGS in the periacetabular region. We did not observe significant graft dissolution. We emphasize that successful graft site remodelling requires meticulous recipient site preparation. Cite this article: Bone Jt Open 2022;3(12):991–997

An uncemented hemispherical acetabular component is the mainstay of acetabular revision and gives excellent long-term results.

Occasionally, the degree of acetabular bone loss means that a hemispherical component will be unstable when sited in the correct anatomical location or there is minimal bleeding host bone left for biological fixation. On these occasions an alternative method of reconstruction has to be used.

A major column structural allograft has been shown to restore the deficient bone stock to some degree, but it needs to be off-loaded with a reconstruction cage to prevent collapse of the graft. The use of porous metal augments is a promising method of overcoming some of the problems associated with structural allograft. If the defect is large, the augment needs to be protected by a cage to allow ingrowth to occur. Cup-cage reconstruction is an effective method of treating chronic pelvic discontinuity and large contained or uncontained bone defects.

This paper presents the indications, surgical techniques and outcomes of various methods which use acetabular reconstruction cages for revision total hip arthroplasty.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):73–7.

We investigated the early results of modular porous metal components used in 23 acetabular reconstructions associated with major bone loss. The series included seven men and 15 women with a mean age of 67 years (38 to 81), who had undergone a mean of two previous revisions (1 to 7).

Based on Paprosky’s classification, there were 17 type 3A and six type 3B defects. Pelvic discontinuity was noted in one case. Augments were used in 21 hips to support the shell and an acetabular component-cage construct was implanted in one case. At a mean follow-up of 41 months (24 to 62), 22 components remained well fixed. Two patients required rerevision of the liners for prosthetic joint instability. Clinically, the mean Harris Hip Score improved from 43.0 pre-operatively (14 to 86) to 75.7 post-operatively (53 to 100). The mean pre-operative Merle d’Aubigné score was 8.2 (3 to 15) and improved to a mean of 13.7 (11 to 18) post-operatively.

These short-term results suggest that modular porous metal components are a viable option in the reconstruction of Paprosky type 3 acetabular defects. More data are needed to determine whether the system yields greater long-term success than more traditional methods, such as reconstruction cages and structural allografts.

The conventional method for reconstructing acetabular bone loss at revision surgery includes using structural bone allograft. The disadvantages of this technique promoted the advent of metallic but biocompatible porous implants to fill bone defects enhancing initial and long-term stability of the acetabular component. This paper presents the indications, surgical technique and the outcome of using porous metal acetabular augments for reconstructing acetabular defects.

Cite this article: Bone Joint J 2013;95-B, Supple A:103–8.

Aims. Bone stock restoration of acetabular bone defects using impaction bone grafting (IBG) in total hip arthroplasty may facilitate future re-revision in the event of failure of the reconstruction. We hypothesized that the acetabular bone defect during re-revision surgery after IBG was smaller than during the previous revision surgery. The clinical and radiological results of re-revisions with repeated use of IBG were also analyzed. Methods. In a series of 382 acetabular revisions using IBG and a cemented component, 45 hips (45 patients) that had failed due to aseptic loosening were re-revised between 1992 and 2016. Acetabular bone defects graded according to Paprosky during the first and the re-revision surgery were compared. Clinical and radiological findings were analyzed over time. Survival analysis was performed using a competing risk analysis. Results. Intraoperative bone defect during the initial revision included 19 Paprosky type IIIA and 29 Paprosky type IIIB hips; at re-revision, seven hips were Paprosky type II, 27 type IIIA and 11 were type IIIB (p = 0.020). The mean preoperative Harris Hip Score was 45.4 (SD 6.4), becoming 80.7 (SD 12.7) at the final follow-up. In all, 12 hips showed radiological migration of the acetabular component, and three required further revision surgery. The nine-year cumulative failure incidence (nine patients at risk) of the acetabular component for further revision surgery was 9.6% (95% confidence interval (CI) 2.9 to 21.0) for any cause, and 7.5% (95% CI 1.9 to 18.5) for aseptic loosening. Hips with a greater hip height had a higher risk for radiological migration (odds ratio 1.09, 95% CI 1.02 to 1.17; p = 0.008). Conclusion. Bone stock restoration can be obtained using IBG in revision hip surgery. This technique is also useful in re-revision surgery; however, a better surgical technique including a closer distance to hip rotation centre could decrease the risk of radiological migration of the acetabular component. A longer follow-up is required to assess potential fixation deterioration. Cite this article: Bone Joint J 2021;103-B(3):492–499

The management of severe acetabular bone defects poses a complex challenge in revision hip arthroplasty. Although biological fixation materials are currently dominant, cage has played an important role in complex acetabular revision in the past decades, especially when a biological prosthesis is not available. The purpose of this study is to report the long-term clinical and radiographic results of Paprosky type Ⅲ acetabular bone defects revised with cage and morselized allografts. We retrospectively analyzed 45 patients who underwent revision hip arthroplasty with cage and morselized allografts between January 2007 and January 2019. Forty-three patients were followed up. There were 19 Paprosky type IIIA bone defect patients and 24 Paprosky type IIIB bone defect patients and 7 patients of the 24 were also with pelvic discontinuity. Clinical assessment included Harris Hip Score (HHS) and Short Form-12 (SF-12). Radiographic assessment included cage stability, allografts incorporation, and center of rotation. All patients were followed up with a mean follow-up of 10.6 years, HHS and SF-12 improved significantly at last follow-up in comparison to the preoperative. There were 2 re-revisions, one at 5 years after surgery, another at 13.6 years after surgery. Two patients had nonprogressive radiolucency in zone III and the junction of zone II and zone III at the bone implant interface. Allografts of 40 (93%) cases incorporated fully. The combination of cage and morselized allograft is an alternative option for acetabular revision with Paprosky type III bone defects with satisfactory long-term follow-up results

In primary total hip arthroplasty (THA) for patients with Crowe II or higher classes developmental dysplasia of the hip (DDH) or rapidly destructive coxopathy (RDC), the placement of the cup can be challenging due to superior and lateral acetabular bone defects. Traditionally, bone grafts from resected femoral heads were used to fill these defects, but bulk graft poses a risk of collapse, especially in DDH with hypoplastic femoral heads or in RDC where good quality bone is scarce. Recently, porous metal augments have shown promising outcomes in revision surgeries, yet reports on their efficacy in primary THA are limited. This study retrospectively evaluated 27 patients (30 hips) who underwent primary THA using cementless cups and porous titanium acetabular augments for DDH or RDC, with follow-up periods ranging from 2 to 10 years (average 4.1 years). The cohort included 22 females (24 hips) and 5 males (6 hips), with an average age of 67 years at the time of surgery. The findings at the final follow-up showed no radiographic evidence of loosening or radiolucency around the cups and augments, indicating successful biological fixation in all cases. Clinically, there was a significant improvement in the WOMAC score from an average of 39.1±14.7 preoperatively to 5.1±6.4 postoperatively. These results suggest that the use of cementless cups and porous titanium acetabular augments in primary THA for DDH and RDC can lead to high levels of clinical improvement and reliable biological fixation, indicating their potential as a viable solution for managing challenging acetabular defects in these conditions

The best treatment method of large acetabular bone defects at revision THR remains controversial. Some of the factors that need consideration are the amount of residual pelvic bone removed during revision; the contact area between the residual pelvic bone and the new implant; and the influence of the new acetabular construct on the centre of rotation of the hip. The purpose of this study was to compare these variables in two of the most used surgical techniques used to reconstruct severe acetabular defects: the trabecular metal acetabular revision system (TMARS) and a custom triflanged acetabular component (CTAC). Pre- and post-operative CT-scans were acquired from 11 patients who underwent revision THR with a TMARS construct for a Paprosky IIIB defect, 10 with pelvic discontinuity, at Royal Adelaide Hospital. The CT scans were used to generate computer models to virtually compare the TMARS and CTAC constructs using a semi-automated method. The TMARS construct model was calculated using postoperative CT scans while the CTAC constructs using the preoperative CT scans. The bone contact, centre of rotation, inclination, anteversion and reamed bone differences were calculated for both models. There was a significant difference in the mean amount of bone reamed for the TMARS reconstructions (15,997 mm. 3. ) compared to the CTAC reconstructions (2292 mm. 3. , p>0.01). There was no significant difference between overall implant bone contact (TMARS 5760mm. 2. vs CTAC 5447mm. 2. , p=0.63). However, there was a significant difference for both cancellous (TMARS 4966mm. 2. vs CTAC 2887mm. 2. , p=0.008) and cortical bone contact (TMARS 795mm. 2. vs CTAC 2560mm. 2. , p=0.001). There was no difference in inclination and anteversion achieved. TMARS constructs resulted on average in a centre of rotations 7.4mm more lateral and 4.0mm more posterior. Modelling of two different reconstructions of Paprosky IIIB defects demonstrated potential important differences between all variables investigated

The Paprosky acetabular bone defect classification system and related algorithms for acetabular reconstruction cannot properly guide cementless acetabular reconstruction in the presence of porous metal augments. We aimed to introduce a rim, points, and column (RPC)-oriented cementless acetabular reconstruction algorithm and its clinical and radiographic outcomes. A total of 123 patients (128 hips) were enrolled. A minimum 5-year radiographic follow-up was available for 96 (75.8%) hips. The mean clinical and radiographic follow-up durations were 6.8±0.9 (range: 5.2–9.2) and 6.3±1.9 (range: 5.0–9.2) years, respectively. Harris hip score (HHS) improved significantly from 35.39±9.91 preoperatively to 85.98±12.81 postoperatively (P<0.001). Among the fixation modes, 42 (32.8%) hips were reconstructed with rim fixation, 42 (32.8%) with three-point fixation without point reconstruction, 40 (31.3%) with three-point fixation combined with point reconstruction, and 4 (3.1%) with three-point fixation combined with pelvic distraction. Complementary medial wall reconstruction was performed in 20 (15.6%) patients. All acetabular components were radiographically stable. Nine-year cumulative Kaplan–Meier survival rates for 123 patients with the endpoint defined as periprosthetic joint infection, any reoperation, and dissatisfaction were 96.91% (confidence interval [CI]: 86.26%, 99.34%), 97.66% (CI: 92.91%, 99.24%), and 96.06% (CI: 86.4%, 98.89%), respectively. Cup stability in cementless acetabular reconstruction depends on rim or three-point fixation. The continuity of the anterior and posterior columns determines whether the points provide adequate stability to the cup. Medial wall reconstruction is an important complementary fixation method for rim or three-point fixation. The patients who underwent cementless acetabular reconstruction guided by the RPC decision-making algorithm demonstrated satisfactory mid-term clinical function, satisfaction levels, radiographic results, and complication rates

Custom acetabular components have become an established method of treating massive acetabular bone defects in hip arthroplasty. Complication rates, however, remain high and migration of the cup is still reported. Ischial screw fixation (IF) has been demonstrated to improve mechanical stability for non-custom, revision arthroplasty cup fixation. We hypothesise that ischial fixation through the flange of a custom acetabular component aids in anti-rotational stability and prevention of cup migration. Electronic patient records were used to identify a consecutive series of 49 custom implants in 46 patients from 2016 to 2022 in a unit specializing in complex joint reconstruction. IF was defined as a minimum of one screw inserted into the ischium passing through a hole in a flange on the custom cup. The mean follow-up time was 30 months. IF was used in 36 cups. There was no IF in 13 cups. No difference was found between groups in age (68.9 vs. 66.3, P = 0.48), BMI (32.3 vs. 28.2, P = 0.11) or number of consecutively implanted cups (3.2 vs. 3.6, P = 0.43). Aseptic loosening with massive bone loss was the primary indication for revision. There existed no difference in Paprosky grade between the groups (P = 0.1). 14.2% of hips underwent revision and 22.4% had at least one dislocation event. No ischial fixation was associated with a higher risk of cup migration (6/13 vs. 2/36, X2 = 11.5, P = 0.0007). Cup migration was associated with an increased risk for all cause revision (4/8 vs. 3/38, X2 = 9.96, P = 0.0016, but not with dislocation (3/8 vs. 8/41, X2 = 1.2, P = 0.26). The results suggest that failure to achieve adequate ischial fixation, with screws passing through the flange of the custom component into the ischium, increases the risk of cup migration, which, in turn, is a risk factor for revision

Aims. Various surgical techniques have been described for total hip arthroplasty (THA) in patients with Crowe type III dislocated hips, who have a large acetabular bone defect. The aim of this study was to evaluate the long-term clinical results of patients in whom anatomical reconstruction of the acetabulum was performed using a cemented acetabular component and autologous bone graft from the femoral neck. Methods. A total of 22 patients with Crowe type III dislocated hips underwent 28 THAs using bone graft from the femoral neck between 1979 and 2000. A Charnley cemented acetabular component was placed at the level of the true acetabulum after preparation with bone grafting. All patients were female with a mean age at the time of surgery of 54 years (35 to 68). A total of 18 patients (21 THAs) were followed for a mean of 27.2 years (20 to 33) after the operation. Results. Radiographs immediately after surgery showed a mean vertical distance from the centre of the hip to the teardrop line of 21.5 mm (SD 3.3; 14.5 to 30.7) and a mean cover of the acetabular component by bone graft of 46% (SD 6%; 32% to 60%). All bone grafts united without collapse, and only three acetabular components loosened. The rate of survival of the acetabular component with mechanical loosening or revision as the endpoint was 86.4% at 25 years after surgery. Conclusion. The technique of using autologous bone graft from the femoral neck and placing a cemented acetabular component in the true acetabulum can provide good long-term outcomes in patients with Crowe type III dislocated hips. Cite this article: Bone Joint J 2021;103-B(2):299–304

Reconstruction of massive acetabular bone defects in primary and revision THA is challenging for reconstructive joint surgeons. The use of porous metal augments is one of the options. The advantages of porous metal augments are easy to use, modularity and lack of resorption. We investigated the radiological results of porous metal augments used for massive acetabular bone defects in primary and revision THA. Forty-one hips in forty patients had porous metal augments between 2011 and 2016. Thirty of the procedures were revision arthroplasties and 11 were primary procedures (Crowe type III in 5 hips, Crowe type IV in 3, septic hip sequalae in 2 and RA in one). Four of the revisions were second-stage reimplantation after infection. The Paprosky classification for revision was 2B in 4 hips, 2C in one, 3A in 3 and 3B in 22. Regenerex augments were used in 39 hips and trabecular metal augments were used in 2. Thirty-six cups were cemented and 5 cups were uncemented. Mean follow-up was 37.6 months (range, 1–82). Radiographic findings of osteointegration between host bone and the porous metal augments were assessed. The presence or absence of radiolucent lines between cement or cup/host bone and augment/host bone interface was noted. Two revisions were performed due to infection, one month and 66 months after operation. The other implants were stable without any complications. Osteointegration between host bone and the porous metal augments were recognized in 36 hips. Radiolucent lines between cement/host bone interface, less than 1 mm in width, were visualized in 2 hips. Porous metal augments are convenient and our short-term results showed excellent radiological results for massive acetabular bone defects in primary and revision THA

We retrospectively evaluated 42 hips which had undergone acetabular reconstruction using the Kerboull acetabular reinforcement device between September 1994 and December 1998. We used autogenous bone chips from the ilium and ceramic particle morsellised grafts, even in large acetabular bone defects, in the early stages of the study. Thereafter, femoral head allograft was used as bulk graft in patients with large acetabular defects. Ceramic blocks and the patients’ contralateral femoral head were also used as bulk graft. The mean follow-up period was 8.7 years (4.3 to 12). Survivorship analysis was performed using radiological failure of the acetabular component, irrespective of whether it was revised, or not, as the end-point. The survival rate of the morsellised graft group (25 hips) and the bulk graft group (17 hips) at ten years was 53% (95% confidence interval (CI) 42.5% to 63.5%) and 82% (95% CI 72.4% to 91.6%), respectively. The mid-term results of revision total hip replacement with the Kerboull device were better when bulk graft was used in any size of bone defect

Introduction. Large acetabular bone defects caused by aseptic loosening are common. Reconstruction of large segmental defects can be challenging. Various implants and operative techniques have been developed to allow further acetabular revision in cases where bone stock is poor. Reconstitution of bone stock is desirable especially in younger patients. The aim of the study was to review the clinical and radiological results of hip revision with structural acetabular bone grafts using fresh frozen allograft and cemented components. Method. Between 1990 and 2014, 151 first time revisions for aseptic acetabular loosening with acetabular reconstruction with a fresh frozen structural allograft and cemented components were performed at our hospital. Graft dimensions, number of screws used and socket coverage by the graft were measured on the post-operative AP radiograph. Follow-up radiographs were analysed for socket loosening, quality of graft union, graft and graft resorption. Results. At a mean follow-up of 7 years 11 months (range 0 – 22), 5 patients had died and 24 hips revised (15.9%). One hundred and three hips had a follow-up greater than 5 years. The reasons for re-revision were infection in 1, recurrent dislocation in 4, aseptic stem loosening in 4 and aseptic cup loosening in 21 (13.9%). Survival analysis with revision for aseptic cup loosening as the endpoint was 80.2% at 10 years. Conclusion. The results using solid allograft to reconstruct the acetabulum are encouraging with a follow-up to 22 years. Structural allograft is a good option to reconstruct segmental defects of the acetabulum at revision surgery and we especially advocate its use to reconstitutes bone stock in younger patients

Aims

To investigate the extent of bone development around the scaffold of custom triflange acetabular components (CTACs) over time.

Aims

Pelvic discontinuity is a rare but increasingly common complication of total hip arthroplasty (THA). This single-centre study evaluated the performance of custom-made triflange acetabular components in acetabular reconstruction with pelvic discontinuity by determining: 1) revision and overall implant survival rates; 2) discontinuity healing rate; and 3) Harris Hip Score (HHS).

Aims

The aim of this study was to examine the implant accuracy of custom-made partial pelvis replacements (PPRs) in revision total hip arthroplasty (rTHA). Custom-made implants offer an option to achieve a reconstruction in cases with severe acetabular bone loss. By analyzing implant deviation in CT and radiograph imaging and correlating early clinical complications, we aimed to optimize the usage of custom-made implants.

We retrospectively reviewed 44 consecutive patients (50 hips) who underwent acetabular re-revision after a failed previous revision that had been performed using structural or morcellised allograft bone, with a cage or ring for uncontained defects. Of the 50 previous revisions, 41 cages and nine rings were used with allografts for 14 minor-column and 36 major-column defects. We routinely assessed the size of the acetabular bone defect at the time of revision and re-revision surgery. This allowed us to assess whether host bone stock was restored. We also assessed the outcome of re-revision surgery in these circumstances by means of radiological characteristics, rates of failure and modes of failure. We subsequently investigated the factors that may affect the potential for the restoration of bone stock and the durability of the re-revision reconstruction using multivariate analysis. At the time of re-revision, there were ten host acetabula with no significant defects, 14 with contained defects, nine with minor-column, seven with major-column defects and ten with pelvic discontinuity. When bone defects at re-revision were compared with those at the previous revision, there was restoration of bone stock in 31 hips, deterioration of bone stock in nine and remained unchanged in ten. This was a significant improvement (p <  0.001). Morselised allografting at the index revision was not associated with the restoration of bone stock. . In 17 hips (34%), re-revision was possible using a simple acetabular component without allograft, augments, rings or cages. There were 47 patients with a mean follow-up of 70 months (6 to 146) available for survival analysis. Within this group, the successful cases had a minimum follow-up of two years after re-revision. There were 22 clinical or radiological failures (46.7%), 18 of which were due to aseptic loosening. The five and ten year Kaplan–Meier survival rate was 75% (95% CI, 60 to 86) and 56% (95% CI, 40 to 70) respectively with aseptic loosening as the endpoint. The rate of aseptic loosening was higher for hips with pelvic discontinuity (p = 0.049) and less when the allograft had been in place for longer periods (p = 0.040). . The use of a cage or ring over structural allograft bone for massive uncontained defects in acetabular revision can restore host bone stock and facilitate subsequent re-revision surgery to a certain extent. Cite this article: Bone Joint J 2014;96-B:319–24

Aims

After failed acetabular fractures, total hip arthroplasty (THA) is a challenging procedure and considered the gold standard treatment. The complexity of the procedure depends on the fracture pattern and the initial fracture management. This study’s primary aim was to evaluate patient-reported outcome measures (PROMs) for patients who underwent delayed uncemented acetabular THA after acetabular fractures. The secondary aims were to assess the radiological outcome and the incidence of the associated complications in those patients.