Introduction. During revision total hip arthroplasty, successful treatment of acetabular bone loss with an associated chronic pelvic discontinuity is dependent upon the remaining bone stock, stability of the construct, potential for biologic fixation, and healing of the discontinuity. Several techniques have been described for the treatment of this clinical entity; the authors recommend the use of acetabular distraction technique in conjunction with a jumbo cup with or without augments. The authors recently evaluated the minimum two-year follow-up of acetabular distraction technique for the treatment of chronic pelvic discontinuity. In the process, a chronic pelvic discontinuity classification was created based on the type of reconstruction required. The purpose of this study is to introduce the initial observations of this novel classification system. Methods. Patients from two academic institutions undergoing acetabular distraction for chronic pelvic discontinuity were identified between January 2002 and December 2013 with minimum 2-year follow-up. Radiographs at latest follow-up were compared to serial radiographs from the index surgery. Data was collected by chart review in accordance with institutional IRB protocol from both institutions. Results. A cohort of 32 patients had minimum 2-year (range, 2.1–13.3 years) follow-up. Mean patient age was 67 years (range, 44–86) and 87% were female. All patients had a chronic pelvic discontinuity with the following bone loss patterns: 7 (22%) type IIC, 5 (15%) type IIIA and 20 (63%) type IIIB. At time of final follow-up, radiographs demonstrated 22 of 32 patients (69%) had evidence of a healed discontinuity. Chronic Pelvic Discontinuity Classification. The classification mirrors the Paprosky classification and requires a more complex reconstruction with each progressive type. For the 20 patients with a type IIIB acetabular bone loss pattern, the new classification was applied. The distribution of classification types was as follows: type I 6 (30%); type II 5 (25%); type IIIA 4 (20%); type IIIB 5 (25%); and type IV 0. Overall, 70% (14) patients required the use of an augment for acetabular reconstruction. Conclusions. Acetabular distraction has been established as an effective method by which to treat chronic pelvic discontinuity. The new classification helps to determine the complexity of reconstruction required for each discontinuity, especially when assessing the most severe acetabular defects (Paprosky IIIB). The authors advocate acetabular distraction with a jumbo cup and modular porous metal augments as the preferred treatment for acetabular bone loss with associated chronic pelvic discontinuity. According to the new classification, the likelihood of utilizing augment(s) increases with severity of bone loss. Future studies are required to validate this new chronic pelvic discontinuity classification

Aims. The aim of this study was to examine the results of the acetabular distraction technique in achieving implantation of a stable construct, obtaining biological fixation, and producing healing of chronic pelvic discontinuity at revision total hip arthroplasty. Patients and Methods. We identified 32 patients treated between 2006 and 2013 who underwent acetabular revision for a chronic pelvic discontinuity using acetabular distraction, and who were radiographically evaluated at a mean of 62 months (25 to 160). Of these patients, 28 (87.5%) were female. The mean age at the time of revision was 67 years (44 to 86). The patients represented a continuous series drawn from two institutions that adhered to an identical operative technique. Results. Of the 32 patients, one patient required a revision for aseptic loosening, two patients had evidence of radiographic loosening but were not revised, and three patients had migration of the acetabular component into a more stable configuration. Radiographically, 22 (69%) of the cohort demonstrated healing of the discontinuity. The Kaplan–Meier construct survivorship was 83.3% when using revision for aseptic acetabular loosening as an endpoint. At the time when one patient failed due to aseptic loosening (at 7.4 years), there were a total of seven patients with a follow-up of seven years or longer who were at risk of failure. Conclusion. The acetabular distraction technique demonstrates encouraging radiographic outcomes, with healing of the discontinuity in over two-thirds of our series. This surgical technique permits biological fixation and intraoperative customization of the construct to be implanted based on the pattern of the bone loss identified following component removal. Cite this article: Bone Joint J 2018;100-B:909–14

The treatment of severe acetabular bone loss is challenging, especially in the setting of an associated chronic pelvic discontinuity. There are several available treatment options for chronic pelvic discontinuity, each of which has its own disadvantages. One of the major difficulties with this entity, regardless of the reconstructive technique chosen, is the inability to obtain reproducible healing of the discontinuity. We evaluated the use of acetabular distraction, a technique which achieves peripheral or lateral distraction and central or medial compression across the discontinuity. We recommend acetabular distraction to allow for implantation of a stable construct, achieve biologic fixation and increase the likelihood of discontinuity healing. In this multi-center trial, 32 patients that underwent acetabular revision for a chronic pelvic discontinuity using acetabular distraction were radiographically evaluated at a minimum of 25 months (range, 25 to 160 months). The study cohort was categorized according to the Paprosky acetabular bone loss classification: seven (22%) type IIC, five (16%) type IIIA, and 20 (62%) type IIIB defects. Fourteen (70%) of the 20 patients with a type IIIB acetabular bone loss pattern required use of augments for acetabular reconstruction. Of the 32 patients, 1 (3%) patient required a revision for aseptic loosening, 2 (6%) patients had evidence of radiographic loosening but were not revised, and 3 (9%) patients had migration of the acetabular component into a more stable position. Radiographically, 22 (69%) of the cohort demonstrated healing of the discontinuity. The Kaplan-Meier construct survivorship was 83.3% when using aseptic acetabular loosening as an end-point. During this study, the authors created a new pelvic discontinuity classification based on the type of reconstruction required. The classification mirrors the Paprosky acetabular bone loss classification. A Type I chronic pelvic discontinuity required jumbo cup reconstruction without augments. A type II discontinuity required the use of an augment for an extracavitary defect. A type III discontinuity required an augment for an intracavitary defect. Type III defects were further subdivided into type IIIA and IIIB discontinuity. Type IIIA discontinuities utilized an augment to reconstruct the anterosuperior and/or posteroinferior column defect for primary stability of the overall construct. Type IIIB discontinuities utilized augments to reconstruct the anterosuperior and/or posteroinferior column defect for primary stability as well as a posterosuperior augment for supplemental fixation. All augments were unitized to the cup with cement. Type IV defects were massive defects that required the use of two orange-slice augments, secured together with screws and placed centrally to restore the defect, and a cup implanted and unitized to the augments with cement. According to this new classification, the discontinuity reconstructions in our study were classified as follows: 12 (38%) type I, 8 (25%) type II, 6 (19%) type IIIA, 6 (19%) type IIIB, and 0 as type IV. Acetabular distraction technique demonstrates favorable radiographic outcomes with reproducible discontinuity healing in a majority of cases. This alternative technique allows for biologic fixation and intra-operative customization of the construct to be implanted based on the bone loss pattern present following component removal

Chronic pelvic discontinuity (CPD) during revision hip arthroplasty is a challenging entity to address. The aim of this study was to evaluate the clinical and radiologic outcomes, and complications of the “acetabular distraction technique” for the management of CPD during revision hip arthroplasty. Patients with CPD, who underwent acetabular revision between 2014 and 2022 at two tertiary care centres, using an identical distraction technique, were evaluated. Demographic parameters, pre-operative acetabular bone loss, duration of follow-up, clinical and radiologic outcomes, and survivorship were evaluated. In all, 46 patients with a mean follow-up of 34.4 (SD=19.6, range: 24–120) months were available for evaluation. There were 25 (54.3%) male, and 21 (45.7%) female patients, with a mean age of 58.1 (SD=10.5, range: 40–81) years at the time of revision surgery. Based on the Paprosky classification of acetabular bone loss, 19 (41.3%), 12 (26.1%), and 15 (32.6%) patients had type 3b, 3a, and 2c defects. All patients were managed using the Trabecular Metal™ Acetabular Revision System; 16 patients required additional Trabecular Metal™ augments. The mean HHS improved from 50.1 (SD=7.6, range: 34.3 – 59.8) pre-operatively, to 86.6 (SD=4.2, range: 74.8 -91.8) at the last follow-up. Two patients (4.3 %) developed partial sciatic nerve palsy, two (4.3%) had posterior dislocation, and one (2.2%) required re-revision for aseptic loosening. Radiologically, 36 (78.3%) patients showed healing of the pelvic discontinuity. The Kaplan-Meier construct survivorship was 97.78% when using re-revision for aseptic acetabular loosening as an endpoint. The acetabular distraction technique has good clinical and radiologic outcomes in the management of CPD during revision hip arthroplasty

The advent of trabecular metal (TM) augments has revolutionized the management of severe bone defects during acetabular reconstruction. The purpose of this study was to evaluate patients undergoing revision total hip arthroplasty (THA) with the use of TM augments for reconstruction of Paprosky 3A, 3B defects and defects associated with pelvic discontinuity. A retrospective study was conducted of the cases performed at four centers between August 2007 and January 2015. Patients treated with TM augments for Paprosky 3A, 3B or chronic pelvic discontinuity were included in the study. All surgeries were performed through a posterior approach. A total of 57 patients (Male 34 (69%), Female 23(31%)), mean age 54 years (range, 28–94 years), with minimum follow up of one-year were included and evaluated using intention to treat analysis. There were 44 (77%) patients with a 3A defect, 11(19%) patients with a 3B defect (6 had an associated pelvic discontinuity), and 2 (3.5%) with a 2C defect and associated pelvic discontinuity. The mean follow-up was 37 months (range, 12–96 months). One (2%) patient died after 8 years of unrelated causes. Three (5.5%) patients had acetabular component loosening requiring revision; Two failures were (3.5%) due to aseptic loosening and one (2%) due to septic loosening. Fifty-four patients had a radiologically stable integration of the components at latest follow-up - survivorship was 94.7%. The results of this multi-center study demonstrate encouraging short and mid-term results for the use of TM augments in the management of Grade 3A and 3B defects, and defects associated with a chronic pelvic discontinuity

Acetabular bone loss is a challenging problem facing the revision total hip replacement surgeon. Reconstruction of the acetabulum depends on the presence of anterosuperior and posteroinferior pelvic column support for component fixation and stability. The Paprosky classification is most commonly used when determining the location and degree of acetabular bone loss. Augments serve the function of either providing primary construct stability or supplementary fixation. . When a pelvic discontinuity is encountered we advocate the use of an acetabular distraction technique with a jumbo cup and modular porous metal acetabular augments for the treatment of severe acetabular bone loss and associated chronic pelvic discontinuity. Cite this article: Bone Joint J 2014;96-B(11 Suppl A):36–42

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).

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.

A pelvic discontinuity occurs when the superior and inferior parts of the hemi-pelvis are no longer connected, which is difficult to manage when associated with a failed total hip replacement. Chronic pelvic discontinuity is found in 0.9% to 2.1% of hip revision cases with risk factors including severe pelvic bone loss, female gender, prior pelvic radiation and rheumatoid arthritis. Common treatment options include: pelvic plating with allograft, cage reconstruction, custom triflange implants, and porous tantalum implants with modular augments. The optimal technique is dependent upon the degree of the discontinuity, the amount of available bone stock and the likelihood of achieving stable healing between the two segments. A method of treating pelvic discontinuity using porous tantalum components with a distraction technique that achieves both initial stability and subsequent long-term biological fixation is described.

Cite this article: Bone Joint J 2014;96-B(11 Suppl A):73–7.