Evidence map›Paper›PMID 40278854›Full record

ArticleInternational orthopaedics2025

Impact of low body mass index on reoperation risk and complications after joint arthroplasty: a cohort study.

Pakpoom Ruangsomboon, Onlak Ruangsomboon, Ossama Al-Obaedi, Darius Luke Lameire, Daniel Pincus, Johnathan Robert Lex, Sebastian Tomescu, Bheeshma Ravi

Abstract read
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Article in International orthopaedics, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

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0cells of the map it votes in
2citing papers in PubMed
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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

2 citing papers in PubMed.

  1. Outcomes of primary total hip arthroplasty in patients who have a BMI less than 20.European journal of orthopaedic surgery & traumatology : orthopedie traumatologie · 2026
    Article
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4 · The record

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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.

Pakpoom RuangsomboonSunnybrook Holland Orthopaedic and Arthritic Centre, Division of Orthopaedic Surgery, University of Toronto, Ontario, Toronto, Canada. pakpoom.ruangsomboon@mail.utoronto.ca.
Onlak RuangsomboonFaculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Ossama Al-ObaediSunnybrook Holland Orthopaedic and Arthritic Centre, Division of Orthopaedic Surgery, University of Toronto, Ontario, Toronto, Canada.
Darius Luke LameireDivision of Orthopaedic Surgery, Department of Surgery, University of Toronto, Toronto, Canada.
Daniel PincusSunnybrook Holland Orthopaedic and Arthritic Centre, Division of Orthopaedic Surgery, University of Toronto, Ontario, Toronto, Canada.
Johnathan Robert LexDivision of Orthopaedic Surgery, Department of Surgery, University of Toronto, Toronto, Canada.
Sebastian TomescuSunnybrook Holland Orthopaedic and Arthritic Centre, Division of Orthopaedic Surgery, University of Toronto, Ontario, Toronto, Canada.
Bheeshma RaviSunnybrook Holland Orthopaedic and Arthritic Centre, Division of Orthopaedic Surgery, University of Toronto, Ontario, Toronto, Canada.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeThe risks associated with low body mass index (BMI) in arthroplasty patients are underexplored. While outcomes of patients with elevated BMI are well-documented, low BMI patients may also face unique challenges, including malnutrition, osteopenia, and increased surgical risks and postoperative complications. To evaluate the impact of low BMI on reoperation risk and other complications compared with normal BMI among patients undergoing total hip or knee arthroplasty.

methodsThis retrospective cohort study analyzed electronic health records of patients with BMI < 25 kg/m² who underwent hip or knee arthroplasty at Sunnybrook Holland Orthopaedic & Arthritic centre, Toronto, Canada between April 2, 2012, and April 6, 2023. Patients were stratified into low BMI (< 20 kg/m²) and normal BMI (20-24.9 kg/m²) groups, with their outcomes followed until November 2024. The main exposure was BMI categorized as low or normal. Other covariates controlled for were relevant demographics and comorbidities. The primary outcome was the risk of reoperation. The secondary outcome was composite complications (persistent pain, wound issues, and radiographic abnormalities). Survival analysis was performed with probabilities visualized with Kaplan-Meier curves. Multivariate Cox proportional hazards models were employed adjusting for potential confounders.

resultsAmong 1,162 included patients (mean [standard deviation] age, 68.8 [11.1] years; 70.1% women), 182 (15.7%) had low BMI and 980 (84.3%) had normal BMI. Kaplan-Meier curves demonstrated significantly higher risks of reoperation and composite complications in patients with low BMI compared to those with normal BMI (both p < 0.001). After adjusting for other covariates, low BMI was independently associated with increased risks of reoperation (adjusted Hazard Ratio (aHR), 5.8; 95% confidence interval (CI), 2.8-12.1; p < 0.001) and composite complications (aHR, 7.5; 95% CI, 3.9-14.5; p < 0.001).

conclusionsIn this large cohort of arthroplasty patients, BMI < 20 kg/m² was associated with elevated risks of reoperation and composite complications. These findings emphasize the importance of tailored preoperative optimization and vigilant postoperative care for this high-risk population. LEVEL OF EVIDENCE: Level III.

Indexed as

Arthroplasty, Replacement, HipArthroplasty, Replacement, KneeBody Mass IndexPostoperative ComplicationsReoperationAgedCohort StudiesFemaleHumansMaleMiddle AgedRetrospective StudiesRisk FactorsBMI < 20ComplicationLow BMILow body mass indexReoperationTotal hip arthroplastyTotal knee arthroplasty

Identifiers

PMID40278854
PMCPMC12179008

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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.