Are adverse outcome rates higher in multiple sclerosis patients after total hip arthroplasty?

Multiple sclerosis is associated with adverse outcomes following hip and knee arthroplasty: A systematic review and meta-analysis of observational studies

BACKGROUND

The association of multiple sclerosis (MS) with joint diseases has been established. However, the impact of MS on postoperative outcomes following total joint arthroplasty (TJA) remains controversial. Therefore, a systematic review of the literature is warranted to ascertain the relationship between MS and adverse outcomes post-TJA.

METHODS

A systematic literature search of PubMed, Embase, Scopus, and the Cochrane Library from inception to 1 March 2023 was conducted to identify observational studies comparing post-TJA outcomes in MS and non-MS patients. Two investigators independently screened titles, abstracts, and full-text articles for eligibility. A random-effects model was used to calculate odds ratios (OR), mean differences (MD), and corresponding 95% confidence intervals (CI).

RESULTS

Seven retrospective cohort studies published between 2018 and 2022 met the inclusion criteria. Patients with MS had a higher risk of medical, surgical, and overall complications than patients without MS. Similarly, the MS group was more likely to experience an extended hospital stay, non-home discharge, and revision surgery compared to the control group. Joint infection and implant instability were also more common in patients with MS.

CONCLUSION

Although TJA may benefit MS patients, current evidence suggests that their postoperative outcomes may be inferior to those of non-MS patients. Thus, orthopaedic surgeons should inform MS patients of potential risks and perform preoperative optimization individually when considering elective arthroplasty.

Total Hip Arthroplasty in Patients With Neurological Conditions: A Systematic Review

Background

As operative techniques and implant design have evolved over time, total hip arthroplasty (THA) is increasingly being carried out for patients with neurological impairment. This patient group places unique surgical challenges to the arthroplasty surgeon, which may include contractures, instability, and altered muscular tone. The purpose of this systematic review is to report the patient outcomes, complications, and implant survival following THA for patients with neurological conditions affecting the hip. Thus, we aim to support orthopaedic surgeon decision-making when considering and planning THA for these patients.

Methods

A systematic review was performed as per Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using the PubMed/Medline OVID, Cochrane, and Embase databases. All studies reporting the outcomes of THA in the neurological population which met defined inclusion criteria were included.

Results

From an initial screen of 1820 studies, 45 studies with a total of 36,251 THAs were included in the final selection. All 45 studies reported complication rates, with controls included in 16 for comparison. High complication rates were observed following THA in the neurologically impaired population, most notably dislocation with observed rates up to 10.6%. An improvement was noted in all 36 studies (1811 THAs) which reported upon patient-reported outcomes.

Conclusions

THA may be beneficial in the selected patients with neurological conditions, to reduce pain and improve function. There is an increased risk of complications which require careful consideration when planning the operation and open discussion with prospective patients and caregivers before proceeding with surgery.

Early failure of a highly cross-linked polyethylene inlay after total hip arthroplasty probably due to insufficient irradiation

Highly cross-linked polyethylene (XLPE) is a major advance in total hip arthroplasty (THA), as it suffers from less wear and thus is associated with lower revision rates than standard ultra-high molecular weight polyethylene. Early failures are reported rarely, and associated with specific design or manufacturing issues. We report a case requiring early revision due to adverse reaction to polyethylene particles. Investigations identified insufficient irradiation as the most probable cause of failure. Here are reported the features of a clinical case with determination of the material properties of the retrieved XLPE liner and establishment of the appropriate calibration curves as reference. Periprosthetic joint infection could be ruled out with appropriate sampling as cause for the inflammatory periarticular tumour. Histology identified a massive macrophagic reaction to micrometric polyethylene particles. No component malposition was present, nor any third-body wear. The trans-vinylene index (TVI) indicated insufficient and potentially detrimental irradiation of the polyethylene, while gel content, crystallinity, melting temperature and oxidation index remained within expected ranges. Histologically proven failure of a XLPE THA liner was identifiable despite correct implantation of the components. The cause of failure most probably was an inadequate irradiation, as indicated by determination of the TVI. This case underscores the importance of histologic workup even in aseptic revisions, and of detailed analysis of retrievals. The calibration curves provided are essential for analysis of other retrievals.