Outcome of the Stryker® Trident 'All-Poly' constraint acetabular insert: a district general hospital experience

Articulating Hip Spacers with a Constrained Acetabular Liner: Effect of Acetabular Bone Loss and Cementation Quality

Articulating hip spacers for periprosthetic joint infection (PJI) offer numerous advantages over static spacers such as improved patient mobilization, hip functionality, and soft tissue tension. Our study aimed to determine complication rates of a functional articulating spacer using a constrained liner to determine the role of acetabular cementation mantle and bone loss on the need for second-stage surgery. A retrospective review of 103 patients was performed and demographic information, spacer components and longevity, spacer-related complications, reinfection rates, and grade of bone loss and acetabular cement mantle quality were determined. There was no significant difference in spacer-related complications or reinfection rate between PJI and native hip infections. 33 of 103 patients (32.0%) elected to retain their spacers. Between patients who retained their initial spacer and those who underwent reimplantation surgery, there was not a significant difference in cement mantle grade (p = 0.52) or degree of bone loss (p = 0.78). Functional articulating antibiotic spacers with cemented constrained acetabular liners demonstrate promising early results in the treatment of periprosthetic and native hip infections. The rate of dislocation events was low. Further efforts to improve cement fixation may help decrease the need for second-stage reimplantation surgery.

Constrained liners revisited: favourable mid-term results in patients with high-risk of dislocation: technical considerations for the optimal outcome

BACKGROUND

The outcomes of constrained liners (CLs) in total hip arthroplasty (THA) remain inconclusive. We evaluated the mid-term performance of CLs in a consecutive series of high-risk dislocation patients undergoing primary or revision THA performed by a single surgeon. The survival, dislocation rate, complications, and functional patients' scores were assessed. Surgical tips to enhance outcomes were reviewed.

METHODS

45 patients who received the Trident Tripolar CL between 2010 to 2019 were retrospectively evaluated from Arthroplasty Registry Thessaloniki. There were 17 primary and 28 revision THAs. The primary indications for using CL were severe abductor insufficiency or comorbidities, increasing the dislocation risk in primary, and recurrent dislocation or abductor insufficiency in revision THAs. The mean patient's age was 68.5 (±14.5) years, and the mean follow-up 3.81 (±1.66) years.

RESULTS

There were 2 dislocations and 1 deep infection in the revision group. For any reason, the cumulative 6-year survival rate was 93.3%, 100% for primary, and 89.3% for revision THAs. The mean overall CL survival was 76.3 months for any reason (95% CI, 68.1-84.5) and 80.5 months for dislocation (95% CI, 75.8-85.2). The mean postoperative functional scores were significantly improved (p < 0.001) at the latest follow-up.

CONCLUSIONS

CLs can provide hip stability and durable fixation in selected low-demand patients with high-risk for dislocation after primary and revision THA at mid-term follow-up. Careful patient selection and the refined surgical technique aiming at the neutral liner position and considering the high CLs' offset relative to stem-neck impingement are necessary to maximise outcomes.

Survivorship and Clinical Outcomes of Constrained Acetabular Liners in Primary and Revision Total Hip Arthroplasty: A Systematic Review

BACKGROUND

Several studies have evaluated the survivorship and clinical outcomes of constrained acetabular liners (CALs) in complex primary and revision total hip arthroplasty with hip instability; however, there remains no consensus on the overall performance of this constrained implant. We therefore performed a systematic review of the literature to examine survivorship and complication rate of CAL usage.

METHODS

A systematic review of the literature in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed. A comprehensive search of PubMed, MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews was conducted for English articles using various combinations of keywords.

RESULTS

In all, 37 articles met the inclusion criteria. A total of 4152 CALs were implanted. The all-cause reoperation-free survivorship was 79.9%. The overall complication rate was 22.2%. Dislocation was the most common complications observed and the most frequent reason for reoperation with an incidence of 9.4% and 9.2%, respectively. Infection after CAL placement had an incidence of 4.6%. The reoperation rate for aseptic acetabular component loosening was 2.9%. Overall, patients had improved outcomes as documented by postoperative hip scores.

CONCLUSION

CALs usage have a relatively high complication rate, particularly when compared with current bearing alternatives (dual mobility cups and large diameter femoral heads), however, it remains a valuable salvage procedure in complex patients affected by recurrent dislocation and implant instability. Newer designs have shown reduced impingement and higher survivorship free from dislocation. However, CALs should only be used when the reasons of instability have been correctly recognized and optimized.