Cementless cup supporter for protrusio acetabuli in patients with rheumatoid arthritis

Total Hip Arthroplasty in Protrusio Acetabuli: A Systematic Review

Protrusio acetabuli, or abnormal protrusion of the femoral head into the acetabulum, requires performance of a total hip arthroplasty (THA) for which various reconstruction techniques and outcomes have been described. The aim of this systematic review is to provide a comprehensive analysis of the current evidence, evaluate treatment efficacy, compare surgical techniques, and identify topics for future research along with improving evidence-based decision-making, improving patient outcomes in the management of this condition. A thorough systematic review of the PubMed, Embase, Cochrane Library databases, and Scopus library was conducted, and articles describing techniques of THA for treatment of protrusion acetabuli were extracted. The initial search generated 751 results. After exclusion, 18 articles were included. Of these, eight were prospective studies and 10 were retrospective. Surgery was performed on 783 hips with a mean age of 60 years; 80% of females who mostly had inflammatory arthritis were followed up for 8.86 years (range, 2-15.4 years). Good outcomes have been achieved with THA using uncemented cups with bone graft; however, no conclusion could be drawn with regard to the femoral side. It can be concluded that the concept of restoration of the anatomical hip center of rotation is paramount for good outcome and better survival of the implant is important when using uncemented cups with a bone graft. In addition, screw augmentation for fixation is not recommended unless absolutely necessary. The most common complications were aseptic loosening and heterotopic ossification. While the former required revision, conservative management was administered for the latter.

Outcomes of Total Hip Arthroplasty in Patients With Acetabular Protrusio

Background:

Acetabular protrusio (AP) is associated with distorted anatomic landmarks and insufficient bone stock that increases complexity of total hip arthroplasty (THA). This study used a large national database to compare outcomes after THA in patients with and without AP.

Methods:

The Nationwide Readmissions Database was used to identify patients with and without AP who underwent THA from 2010 to 2014. Primary outcomes analyzed included complications during index hospitalization and within 90 days of THA.

Results:

Propensity score matching generated 4,395 patients without AP and 4,603 patients with AP. Patients with AP were older (68.1 versus 65.2 years, P < 0.0001), more predominantly women (82.1% versus 55.9%), and had more medical comorbidities as measured by the Elixhauser Comorbidity Index (2.29 versus 1.89, P < 0.0001). Patients with AP had an increased risk of requiring bone graft (odds ratio [OR] = 47.97, 95% confidence interval [CI]: 14.27 to 161.22), receiving a blood transfusion (OR = 1.90, 95% CI: 1.57 to 2.29), and suffering a periprosthetic fracture (OR = 2.56, 95% CI: 1.10 to 5.97) within 90 days of THA. Length and cost of index hospitalization were greater for patients with AP (5.0 versus 4.3 days, P = 0.002; $19,211.88 versus $27,736.30, P < 0.0001).

Conclusion:

Given the current emphasis on hospital cost optimization, it is important to ensure that patients with AP are managed appropriately. Attention should be placed on comprehensive preoperative planning and postoperative monitoring in this population.

Revision Total Hip Arthroplasty Using a Cementless Cup Supporter and Iliac Autograft: A Minimum of 15-Year Follow-Up

BACKGROUND

Bone deficiency in revision total hip arthroplasty is a surgical challenge. The Murata-Chiba cup supporter (MC support ring) is an acetabular component supporter for a cementless porous-coated cup. The purpose of this study is to examine the clinical and radiographic outcomes of reconstruction of acetabular bone deficiency using iliac autografts supported by an MC support ring in a revision setting with minimum 15-year follow-up.

METHODS

Fifty-nine consecutive revision total hip arthroplasties (57 patients) using the MC support ring were followed for a minimum of 15 years. Nine hips had American Academy of Orthopaedic Surgeons type II deficiency and 24 had type III defects of the acetabulum. Clinical outcomes were evaluated using the Harris hip score. Radiographic evaluation included assessment for loosening and bone graft incorporation. Kaplan-Meier survival analysis was performed.

RESULTS

At a minimum 15-year follow-up (mean, 17.6 years), 32 patients (33 hips) were alive, 17 patients (18 hips) were deceased, and 8 patients (8 hips) were lost to follow-up. The mean Harris hip score improved from 44.3 to 77.2 at final follow-up. Four hips required reoperation due to deep infection (2 hips) and liner dissociation (2 hips), but no acetabular components were revised for aseptic loosening. Incorporation of the bone graft occurred in all cases. One unrevised patient had radiographic failure. Survivorship at 15 years with re-revision or radiographic failure as the end point was 90.6% (95% confidence interval, 83.0%-98.8%).

CONCLUSION

The reconstruction of acetabular bone deficiency using autografts supported by an MC support ring provided satisfactory clinical and radiological results at 17.6 years postoperatively.

Long-term results of the uncemented acetabular component in a primary total hip arthroplasty performed for protrusio acetabuli: a fifteen year median follow-up

PURPOSE

Protrusio acetabuli is an uncommon finding that can be seen in patients undergoing primary total hip arthroplasty for arthritis. Uncemented fixation of the acetabular component and bone grafting of the protrusio defect is commonly used as a reconstruction method and has shown good mid-term results. The long-term outcome of these reconstructions warrants further study. The objective of this study was to determine the results of primary total hip arthroplasty (THA) with use of an uncemented acetabular component for protrusio acetabuli in patients followed for a minimum of ten years.

METHODS

Sixty-five hips in 53 patients had a primary THA with uncemented acetabular component for the protrusio acetabuli between 1984 and 2001. There were 53 procedures performed in females (82%) and 12 in males (18%). The mean age at the procedure was 66 years. Acetabular floor reconstruction with use of bone graft was performed in 58 hips (89%). Four patients (five hips) were lost to follow-up less than ten years after the procedure and 25 patients (31 hips) had died during the follow-up period. The median follow-up of living patients that did not have revisions for acetabular component was 15.4 years (range, ten to 24 years).

RESULTS

During the study duration, six hips underwent acetabular component revision: aseptic loosening (three hips), polyethylene wear (two hips), and recurrent instability (one hip). The median Harris hip score for the living patients who did not have an acetabular component revision improved from 55 points pre-operatively to 82 points at the latest follow-up. At 15 years, the estimated survival rate from revision was 70% for the THA: 85.4% for the acetabular component, and 83% for the femoral component. Five unrevised acetabular components had evidence of non-progressive radiolucency.

CONCLUSIONS

In patients undergoing THA with acetabular protrusio, fixation of an uncemented hemispherical shell and use of bone graft as necessary provided satisfactory clinical and radiographic results as well as satisfactory survivorship rates at a median follow-up of 15 years.

Restoration of the hip center during THA performed for protrusio acetabuli is associated with better implant survival

BACKGROUND

Acetabular protrusio is an uncommon finding in hip arthritis. Several reconstructive approaches have been used; however the best approach remains undefined.

QUESTIONS/PURPOSES

Our purposes in this study were to (1) describe the THA survivorship for protrusio as a function of the acetabular component, (2) evaluate survivorship of the cup as a function of restoration of radiographic hip mechanics and offset, and (3) report the long-term clinical results.

METHODS

One hundred twenty-seven patients (162 hips) undergoing primary THA with acetabular protrusio were retrospectively reviewed. The mean age of the patients at surgery was 66±13 years, and the mean followup was 10±6 years (range, 2-25 years).The cup fixation was uncemented in 107 (83 with bone graft) and cemented in 55 hips (14 with bone graft). Preoperative and postoperative radiographs were reviewed for restoration of hip mechanics and offset.

RESULTS

The THA survival from aseptic cup revision at 15 years was 89% (95% CI, 75%-96%) for uncemented compared with 85% (95% CI, 68%-94%) for cemented cups. The risk of aseptic cup revision significantly increased by 24% (hazards ratio, 1.24; 95% CI, 1.02-1.5) for every 1 mm medial or lateral distance away from the native hip center of rotation to the prosthetic head center. Harris hip scores were improved by mean of 27±20 points (n=123) with a higher postoperative score for uncemented bone grafted compared with solely cemented cups (81±16 versus 71±20 points).

CONCLUSIONS

Restoring hip center of rotation using an uncemented cup with or without bone graft was associated with increased durability in our series. There was a 24% increase in the risk of aseptic cup revision for every 1 mm medial or lateral distance away from the native hip center to the prosthetic head center.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Results of revision total hip arthroplasty with Anatomic BR stem: 10-year minimum follow-up

Twenty cementless total hip revision arthroplasties using Anatomic BR stems were performed in 20 patients. Fourteen patients, with a mean age of 62.6 years (range 41-74 years) at time of revision surgery, were followed retrospectively for a minimum of 10 years (range 11-15 years). Clinical function and radiographic evidence of implant stability were evaluated. Preoperative femoral deficiencies were evaluated radiographically and classified according to Paprosky type as follows: four Type-II, four Type-IIIA, four Type-IIIB, and two Type-IV femurs. Mean preoperative Harris hip score was 46.3 points (range 29-58 points) and improved to 68.8 points (range 45-90 points) at the most recent follow-up examination. Of the 14 patients followed, six had radiographic evidence of subsidence (axial shift of more than 2 mm after revision with long-stem components). Component fixation showed bone ingrowth in three (21%) patients, inconclusive evidence of ingrowth in six (43%) patients, suboptimal but stable fixation in three (21%) patients, and unstable fixation in two (14%) patients. Based on these we results, we conclude that even with circumferential proximal porous coating and improved proximal geometry, nonmodular femoral implant stability remains unpredictable following total hip arthroplasty revision.

Clinical and radiological results of non-cement impaction bone-graft method of total hip arthroplasty for rheumatoid arthritis

We performed total hip arthroplasty using the non-cement impaction auto-bone-grafting method with the resected femoral head for acetabular protrusion that is not combined with the destruction of acetabular rim or dysplasia of the hip joint. Ten patients (eight women and two men) with rheumatoid arthritis who showed acetabular protrusion underwent total hip arthroplasty using this method. All patients were able to walk with full weight within 5 days after surgery. The short-term results of our cases were very good. The postoperative periods of the radiographic-bone incorporation of the grafting bone were 2 months after surgery in four joints, 3 months after surgery in four joints, and 4 months after surgery in three joints. There were no cases that showed any migration or radiolucency around the acetabular component at the time of follow-up. Our operative technique is simple and easy, and it is a useful method for the treatment of protrusion in patients with rheumatoid arthritis.