Acetabular Distraction: Promising 5-Year Outcomes for the Treatment of Chronic Pelvic Discontinuity.

BACKGROUND: Severe acetabular bone loss encountered during revision total hip arthroplasty (THA) poses a clinical challenge. In cases involving pelvic discontinuity, where the ilium is separated superiorly from the inferior ischiopubic segment through the acetabulum, acetabular distraction may be used to restore the biomechanics of the hemipelvis. This technique allows for correct sizing of the acetabulum, and the subsequent peripheral distraction and medial compression at the discontinuity provide initial mechanical stability and biological fixation as bone in growth occurs. Accordingly, this study aimed to assess long-term 5-year outcomes following acetabular distraction across 2 institutions. METHODS: We retrospectively identified all patients who underwent revision THA in which the acetabular distraction technique was performed for the treatment of chronic pelvic discontinuity between 2002 and 2018. Demographic, operative, and clinical postoperative data were collected. Clinical endpoints included postoperative radiographic outcomes, complications requiring additional surgery, and reoperation for all causes. Only patients who had a minimum 5-year follow-up were included in this study. RESULTS: A total of 15 patients (Paprosky IIC: one patient, 6.7%; Paprosky IIIA: 5 patients, 33.3%; Paprosky IIIB: 9 patients, 60%) who had a mean follow-up time of 9 years (range, 5.1 to 13.5) were analyzed. Porous tantalum augments were used in 11 (73.3%) cases to primarily address posteriorsuperior defects (100%). There were 4 (26.7%) patients that required reoperation, only 2 of which were for indications related to the acetabular construct, leading to an overall survivorship of 86.7%. Both patients had a prior revision THA before the implementation of the distraction technique. Evidence of bridging callus formation was reported radiographically for 14 (93.3%) patients at the time of the last clinical follow-up. CONCLUSIONS: For patients who have chronic pelvic discontinuity, acetabular distraction shows promising long-term outcomes. Even so, larger multi-center studies are needed to better support the efficacy of this technique. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Acetabular Distraction Technique: A Multicenter Study With a Minimum 2-Year Radiographic Follow-Up.

BACKGROUND: Chronic pelvic discontinuity is a challenge during revision total hip arthroplasty due to the loss of structural continuity of the superior and inferior aspects of the acetabulum from severe acetabular bone loss. Acetabular distraction provides an alternative surgical treatment by stabilizing the acetabular component through elastic recoil of the pelvis, which may be supplemented with modular porous augments for addressing major acetabular defects. This study reports 2-year radiographic findings following acetabular distraction for the treatment of chronic pelvic discontinuity. METHODS: Patients undergoing acetabular distraction performed by 5 surgeons from 2002 to 2021 were identified across 5 institutions. Demographic, surgical, and postoperative outcomes, including radiographic component stability, were recorded. There were 53 of 91 (58.2%) patients (5 deceased, 33 lost to follow-up) consisting of 4 Paprosky IIC (7.5%), 8 Paprosky IIIA (15.1%), and 41 Paprosky IIIB (77.4%) defects included, with a mean follow-up time of 4.8 years (range, 2 to 13.5). Modular porous augments were used in 33 (62.3%) cases. Failure was defined as a subsequent revision of the acetabular construct. RESULTS: Among the 13 (24.5%) patients who returned to the operating room, 6 (46.2%) had a prior history of revision total hip arthroplasty before undergoing acetabular distraction. Only 5 (9.4%) patients underwent acetabular revision following acetabular distraction, leading to an overall cup survivorship of 90.6%. Of the remaining 48 patients, 46 (95.8%) had evidence of radiographic bridging callus of the chronic pelvic discontinuity at their last clinical follow-up. CONCLUSIONS: To our knowledge, in the largest series to date, acetabular distraction has proven to be a viable treatment for acetabular bone loss with a chronic pelvic discontinuity, with excellent early survivorship and radiographic evidence of bridging callus. Future studies with longer follow-ups are needed to further monitor the efficacy of this technique. LEVEL OF EVIDENCE: Level III, Retrospective Comparative Study.

Survivorship and clinical outcomes of 'cup-cage' reconstruction in revision of hip arthroplasty for chronic pelvic discontinuity: A systematic review.

BACKGROUND: This study was conducted to assess the survivorship and clinical outcomes of cup-cage reconstruction technique in the revision of THA. METHODS: PubMed, OVID, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) up to February 2020 were searched. Studies that reported the clinical and radiological follow-up were identified. RESULTS: A total of 151 hips (145 patients) in six studies were included. The all-cause revision-free survivorship of cup-cage implant at the end of follow-up was 90.1% (136/151), with a mean follow-up of 64.4 months(range 12-135). The overall complication rate was 23.8% (36 of 151 hips), of which component problem, dislocation, infection and sciatic nerve palsy/injury were relatively common. All included studies reported improved clinical outcomes at the end of follow-up. CONCLUSION: Results suggested that revision of THA with a cup-cage has a favourable implant survivorship and clinical outcomes for the treatment of pelvic discontinuity, despite the high complications occurrence rates.

Acetabular Distraction Technique for the Treatment of Chronic Pelvic Discontinuities: Excellent Short-Term Implant Survivorship and Good Clinical Outcomes.

BACKGROUND: Pelvic discontinuity is a challenging complication in revision total hip arthroplasty. One technique that has garnered enthusiasm with limited data is acetabular distraction. Acetabular distraction provides stability via elastic recoil of the pelvis. The aim of this study is to report implant survivorship, radiographic results, clinical outcomes, and complications in the largest independent series of discontinuities treated with acetabular distraction. METHODS: We retrospectively identified all revision total hip arthroplasties with a pelvic discontinuity between 2005 and 2017. Of the 162 patients, 31 were treated with distraction. Mean age was 67 years, with 71% female. Mean body mass index was 28 kg/m2, and mean follow-up was 3 years. RESULTS: The 2-year survivorship free from revision for aseptic loosening, re-revision for any reason, and reoperation were 97%, 93%, and 87%, respectively. There were 3 re-revisions including 1 for aseptic loosening, 1 conversion to a dual mobility for instability, and 1 two-stage exchange for infection. At last follow-up, 3 acetabular components did not have evidence of osteointegration. Only patients with osteointegration to both the ilium and ischium had evidence of a healed discontinuity. The mean Harris Hip Score improved from 43 preoperatively to 77 postoperatively (P < .0001). The most common complication was a partial sciatic nerve palsy that occurred in 4 patients. CONCLUSION: In this series utilizing pelvic distraction, there was excellent 2-year survivorship free from revision for aseptic loosening. Despite several discontinuities persisting, 90% of patients had radiographic evidence of implant osteointegration, and clinical outcomes improved significantly. The most common complication was a partial sciatic nerve palsy. LEVEL OF EVIDENCE: IV Case Series.

Two-centre radiological survivorship of acetabular distraction technique for treatment of chronic pelvic discontinuity: mean five-year follow-up.

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.

Treatment options for chronic pelvic discontinuity.

Chronic pelvic discontinuity is a distinct and unique challenge seen during revision total hip arthroplasty (THA) in which the superior ilium is separated from the inferior ischiopubic segment through the acetabulum, rendering the anterior and posterior columns discontinuous. The operative management of acetabular bone loss in revision THA is one of the most difficult challenges today. Common treatment options include cage reconstruction with bulk acetabular allograft, custom triflange acetabular component, a cup-cage construct, jumbo acetabular cup with porous metal augments, or acetabular distraction with a porous tantalum shell with or without modular porous augments.

Acetabular distraction: an alternative for severe acetabular bone loss and 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.