Evidence map›Paper›PMID 42387606›Full record

ArticleArthroplasty (London, England)2026

25-year follow-up of 102 unrevised cementless total hip arthroplasties with a second-generation metal-on-metal bearing in a young patient cohort.

Moritz von Falkenhayn, Andre Lunz, Max Kempe, Timo A Nees, Kevin-Arno Koch, Moritz M Innmann, Tilman Walker, Tobias Reiner

Abstract read
In one paragraph

Article in Arthroplasty (London, England), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Moritz von Falkenhayn *Department of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Andre Lunz *Department of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Max KempeDepartment of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Timo A NeesDepartment of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Kevin-Arno KochDepartment of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Moritz M InnmannDepartment of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Tilman WalkerDepartment of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany.
Tobias ReinerDepartment of Orthopaedics, Heidelberg University Hospital, Schlierbacher Landstr. 200a, 69118, Heidelberg, Germany. tobias.reiner@med.uni-heidelberg.de.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundSecond-generation metal-on-metal (MoM) bearings were reintroduced in total hip arthroplasty (THA) for their low wear rates, but despite initially promising results, concerns have emerged about adverse reactions to metal debris and poor long-term implant survival, with limited and conflicting evidence regarding the outcomes of small-diameter MoM implants. This study aimed to evaluate implant survival and metal wear complications in young patients with second-generation small-head MoM THA after more than 20 years.

methodsA retrospective cohort study was conducted at a university center, analyzing 179 consecutive THAs in 160 patients aged under 55 years, using a small-head MoM bearing. After a minimum 20-year follow-up, clinical-radiological outcomes and systemic metal ion concentrations were assessed, with Kaplan-Meier analysis determining implant survival rates.

resultsMean patient age at surgery was 46 years. After a mean follow-up of 23 years, 38 (21%) patients had deceased, and 9 (5%) patients were lost to follow-up. A total of 30 (16%) THAs had undergone revision surgery. The reasons for revision were metal wear-related complications in 11 hips (6%), aseptic loosening in 9 hips (5%), periprosthetic fractures in 6 hips (3%), periprosthetic joint infection in 3 hips (2%), and recurrent dislocation in 1 hip (1%). Of the non-revised THAs, the mean WOMAC score was 85.3. Osteolytic lesions were identified in 43% of hips with available radiographs (29/67), and elevated blood chromium or cobalt ion levels (> 2 µg/L) were detected in 22% of hips with available blood samples (11/51). Magnetic resonance imaging with metal artifact reduction sequence (MARS-MRI) was performed in 18 unrevised THAs, revealing a pseudotumor in 3 (17%). Kaplan-Meier survival rates at 25 years were 93% (95% CI: 87%-96%) for metal wear-related revisions and 77% (95% CI: 67%-85%) for any revision.

conclusionsSecond-Generation small-head MoM THA leads to acceptable implant survival rates and joint function more than 20 years after index surgery. Still, metal wear-related complications were the most frequent cause for revision (37%), and periprosthetic osteolysis was present in 43% of hips. This highlights the need for long-term monitoring into the third decade. Considering the superior performance of modern bearings, their use is recommended to avoid wear-related complications and revisions.

Indexed as

Adverse Reactions to Metal DebrisARMDHipImplant SurvivalMetal-on-Metal BearingsMetasulTotal Hip Arthroplasty

Identifiers

PMID42387606
PMCPMC13325570

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.