Early Results of Revision Hip Arthroplasty Using a Ceramic Revision Ball Head

Midterm outcome of fourth-generation ceramic-on-ceramic bearing surfaces in revision total hip arthroplasty

PURPOSE

The purpose of this study is to evaluate the clinical and radiologic outcomes after revision total hip arthroplasty (THA) using fourth-generation ceramic-on-ceramic (CoC) bearing surfaces.

METHODS

A total of 52 revision THAs (28 men and 19 women) using the fourth-generation CoC bearing surfaces were retrospectively evaluated. Both acetabular cup and femoral stem were revised in all cases. The mean follow-up period was 7.3 years (range, 4.0-9.9 years). The clinical results with Harris hip score (HHS), Western Ontario McMaster Osteoarthritis Index (WOMAC), and radiologic outcomes were evaluated.

RESULTS

At the final follow-up examination, the average HHS was 90.4 (range, 67-100). The average WOMAC pain and physical function score were 2.8 (range, 0-12) and 16.4 (range, 0-42), respectively. Complications were observed in 10 hips (19.2%). However, there were no bearing surface-related complications, and no cases of dislocation and squeaking. Retroacetabular pelvic osteolysis without cup loosening was observed in one hip at the final follow-up. However, no hip showed radiographic signs of cup loosening, vertical or horizontal acetabular cup migrations, and changes of inclinations during the follow-up period.

CONCLUSION

Our data showed that clinical and radiologic outcomes after revision THA using fourth-generation CoC bearing were favorable. Hence, revision THA with the use of CoC bearing surfaces can be preferentially considered. Further studies with long-term follow-up data are warranted.

Fretting and Corrosion Damage in Taper Adapter Sleeves for Ceramic Heads: A Retrieval Study

BACKGROUND

During revision surgery with a well-fixed stem, a titanium sleeve can be used in conjunction with a ceramic head to achieve better stress distribution across the taper surface. In vitro testing suggests that corrosion is not a concern in sleeved ceramic heads; however, little is known about the in vivo fretting corrosion of the sleeves. The purpose of this study was to investigate fretting corrosion in sleeved ceramic heads in retrieved total hip arthroplasties.

METHODS

Thirty-seven sleeved ceramic heads were collected during revision. The femoral heads and sleeves were implanted 0.0-3.3 years. The implants were revised predominantly for instability, infection, and loosening. Fifty percent of the retrievals were implanted during a primary surgery. Fretting corrosion was assessed using the Goldberg-Higgs semiquantitative scoring system.

RESULTS

Mild-to-moderate fretting corrosion scores (score = 2-3) were observed in 92% of internal tapers, 19% of external tapers, and 78% of the stems. Severe fretting corrosion was observed in 1 stem trunnion that was previously retained during revision surgery and none of the retrieved sleeves. There was no difference in corrosion damage of sleeves used in primary or revision surgery.

CONCLUSION

The fretting corrosion scores in this study were predominantly mild and lower than reported fretting scores of cobalt-chrome heads in metal-on-polyethylene bearings. Although intended for use in revisions, we found that the short-term in vivo corrosion behavior of the sleeves was similar in both primary and revision surgery applications. From an in vivo corrosion perspective, sleeves are a reasonable solution for restoring the stem taper during revision surgery.

Two-year follow-up of revision total hip arthroplasty using a ceramic revision head with a retained well-fixed femoral component: a case series

Introduction

It is known that a well-fixed stem can be left in situ when only the acetabular component and femoral head have to be changed. However, in a revision case, the use of a ceramic head on an existing taper is not recommended. Slight damages of the taper may increase the risk of a ceramic fracture. Until now in a revision case a primary ceramic-on-ceramic or ceramic-on-polyethylene pairing was changed to a metal-on-polyethylene pairing or the well-fixed stem was removed as well. During the past several years, a ceramic head with a metallic sleeve has been introduced as an option for revisions with a stem left in situ. We report short-term results of a ceramic revision head in this clinical setting.

Methods

Eight patients with a ceramic revision head were clinically and radiologically followed up two years after revision surgery. Their Harris Hip Score and visual analogue scale scores for pain and satisfaction were recorded, and their radiographs were checked for osteolysis and heterotopic ossifications.

Results

The mean Harris Hip Score increased from 46.5 points before surgery to 88.3 points 2 years after surgery. The mean visual analogue scale score for pain improved from 6.7 to 1.1, and the mean visual analogue scale for satisfaction rose from 5.1 to 8.3. The radiological results did not show osteolysis in any of the patients. Grade I heterotopic ossification according to the Brooker classification system was seen in one patient.

Conclusions

The early clinical and radiological results in this case series are in agreement with previously published studies. Ceramic revision heads with a metallic sleeve are a promising approach in the revision of a ceramic head with a well-fixed stem which can be left in situ. This solution avoids an unnecessary exchange of a well-fixed stem and thereby shortens the surgical time of the revision and may reduce the peri-operative complications.

Fracture of a BIOLOX Delta Ceramic Femoral Head Articulating Against a Polyethylene Liner: A Case Report

CASE

A forty-five-year-old woman underwent primary total hip arthroplasty with a 36-mm BIOLOX delta ceramic femoral head articulating against a polyethylene liner. She presented with hip pain at eighteen months postoperatively, two months after being in a bicycle accident; fracture of the femoral head was diagnosed.

CONCLUSION

The possibility of a ceramic femoral head fracture should be decreased with use of the latest generation of ceramic material, a ceramic-on-polyethylene articulation rather than a ceramic-on-ceramic articulation, and a larger head size, all of which applied to this case. Taper-trunnion compatibility and correct intraoperative handling of the components are also essential.

Modular sleeves with ceramic heads in isolated acetabular cup revision in younger patients-laboratory and experimental analysis of suitability and clinical outcomes

PURPOSE

One possibility in hip arthroplasty revisions is to combine a modular ceramic head with an adapter or sleeve in isolated acetabular cup replacement. This study consisted of an experimental part to analyse the reliability of taper damage predictions, and a clinical part to analyse the outcomes of modular ceramic head implantation in a case series of isolated cup replacements.

METHODS

Analysis of scratch size on 11 explanted hip stems were examined macroscopically and by stereomicroscopy to classify damage to the conical taper. The second part consisted of a prospective analysis of isolated cup revisions using a modular ceramic head, performed in two orthopedic centres.

RESULTS

Analysis of scratch size on the taper yielded inter-observer correlations of 0.545-0.909; comparison with stereomicroscopic data recordings yielded a moderate correlation, with values between 0.545 and 0.090. The clinical study included 47 isolated acetabular cup revisions involving modular ceramic heads. Ceramic head failure did not occur during the average clinical and radiological observation period of 26 months. Mean Harris Hip Score (HHS) at follow-up was 70 points.

CONCLUSION

From these results, it can be concluded that damage to the implanted stem taper cannot be reliably predicted intraoperatively. Nevertheless, the clinical outcomes did show that there were no problems with the ceramic heads over the short observation period. The application of modular ceramic heads in younger patients requiring isolated cup replacement requires proper risk-benefit analysis, but is possible and appears to be a safe procedure.