Definition and research guide
This page combines a MeSH definition, publication statistics and selected research abstracts. It is a starting point for reading the literature, not a medical textbook or a systematic evidence review.
Content available: 3 complete abstracts (565 words), 9 references. Full article text is not stored or reproduced here; follow the PMID, DOI or PMC links to read the original sources and their access terms.
Definition
The region of the upper limb in animals, extending from the deltoid region to the HAND, and including the ARM; axilla; and shoulder.
Definition: NLM Medical Subject Headings (MeSH) scope note (Public domain (U.S. National Library of Medicine); attribution requested). View the MeSH record.
Also known as: Extremities, Upper; Upper Extremities; Extremity, Upper; Membrum superius; Upper Limb; Limbs, Upper; Limb, Upper; Upper Limbs.
Where it fits in the MeSH classification
- Broader topics
- Extremities
- Narrower topics
- Arm; Axilla; Elbow; Forearm; Hand; Shoulder; Wrist
- See also
- Bones of Upper Extremity
Related concepts
Research landscape
PubMed indexes 201,625 records tagged with the MeSH heading “Upper Extremity” (counts retrieved 2026-10-31). 36,814 of them (18.3%) were published from 2020 onward, and the busiest period so far is through 1999 with 77,165 records.
Reviews account for 13,647 records (6.8%) and meta-analyses for 1,260. Randomized controlled trials number 8,054 (4.0%) as a share of all records on the topic.
Show the data
| Period | Records |
|---|---|
| through 1999 | 77,165 |
| 2000-2009 | 36,770 |
| 2010-2019 | 50,876 |
| 2020 onward | 36,814 |
Publication-type chart data
| Type | Records | Share |
|---|---|---|
| Reviews | 13,647 | 6.8% |
| Meta-analyses | 1,260 | 0.6% |
| Randomized controlled trials | 8,054 | 4.0% |
Method: PubMed query "Upper Extremity"[MeSH Terms] with publication-type and date filters, retrieved 2026-10-31.
Reading the evidence in anatomy and physiology
Anatomy describes how body structures are built and physiology describes how they normally work, so most findings here are descriptive or mechanistic rather than evidence about treatment. Much of what is known comes from dissection, imaging, tissue studies and experiments in animals, and measurements in healthy volunteers can differ from those in people with disease or at different ages. Normal ranges vary between individuals and populations. Check whether a result was measured in people or in another species, the age and health of the participants, and the method used.
Evidence from open-access studies
These open-access studies come from PubMed’s best-match results for this heading (papers whose main topic it is), ranked here by citation count, with one recent addition. Each abstract is reproduced in full under its recorded open licence so that you can read the authors’ own words. They illustrate the literature; they are not a systematic summary of it. Citation counts measure attention, not reliability or clinical benefit.
| Study / authors | Year | Source label / design | Europe PMC citations | Licence / source |
|---|---|---|---|---|
| The 2D:4D Digit Ratio and Primary Sjögren's Syndrome: A Window Into Prenatal Hormonal Influences on Exocrine Autoimmunity | 2026 | Research article Design not recorded in structured metadata | 3 | cc by PMID 41958154 · DOI · PMC13066761 |
| A neuroprosthesis for restoring hand movement and sensation in a person with complete tetraplegia | 2026 | Research article Design not recorded in structured metadata | 2 | cc by PMID 42463883 · DOI · PMC13375563 |
| Rapid personalized computational modeling of the wrist | 2026 | Research article Design not recorded in structured metadata | 1 | cc by PMID 42392143 · DOI · PMC13465003 |
The 2D:4D Digit Ratio and Primary Sjögren's Syndrome: A Window Into Prenatal Hormonal Influences on Exocrine Autoimmunity [1]
Abstract reading summary — source excerpts
- Opening excerpt
- ObjectivesThe pronounced female preponderance in Sjögren's syndrome (SS) points to a potential role for sex hormones in disease development.
- Closing excerpt
- These findings implicate the prenatal hormonal milieu as a potential contributor to the immunological processes underlying SS pathogenesis.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (210 words)
ObjectivesThe pronounced female preponderance in Sjögren's syndrome (SS) points to a potential role for sex hormones in disease development. The ratio of the second to fourth digit (2D:4D), which serves as an indirect marker of fetal androgen exposure, has shown associations with several immune-mediated conditions. The present study assessed whether 2D:4D ratios are lower in women diagnosed with SS relative to healthy individuals.MethodsIn this case-control investigation, 57 female SS patients (classified per the 2016 ACR/EULAR criteria) and 44 age-matched healthy women were recruited. The lengths of the index and ring fingers were measured on both hands with digital calipers, and digit ratios were derived. Group comparisons were conducted with Welch's t-test and supplemented by Mann-Whitney U-tests.ResultsWomen with SS had lower 2D:4D ratios on both sides (right: 0.938 ± 0.030 vs. 1.011 ± 0.024, p 2.6). Lower ratios were driven predominantly by elongated ring fingers rather than shortened index fingers, a pattern compatible with heightened fetal androgen exposure.ConclusionsWomen with primary SS exhibit lower 2D:4D digit ratios compared with healthy controls, suggesting that a shifted prenatal estrogen-to-androgen balance may prime the immune system toward the glandular autoimmunity and exocrine dysfunction that define this disease. These findings implicate the prenatal hormonal milieu as a potential contributor to the immunological processes underlying SS pathogenesis.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 41958154 · DOI · PMC13066761
A neuroprosthesis for restoring hand movement and sensation in a person with complete tetraplegia [2]
Abstract reading summary — source excerpts
- Opening excerpt
- Millions of people worldwide are living with movement and sensory impairments owing to spinal cord injury, stroke and other neurological conditions.
- Closing excerpt
- These findings demonstrate the potential of combining a sensorimotor neuroprosthesis with targeted brain and spinal neuromodulation to restore clinically relevant function in severe paralysis.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (201 words)
Millions of people worldwide are living with movement and sensory impairments owing to spinal cord injury, stroke and other neurological conditions. Here we report a double neural bypass (DNB), a hybrid neuroprosthetic system designed to restore both immediate and lasting gains in movement and sensation after a severe, complete spinal cord injury. The DNB links an intracortical brain-computer interface with targeted and patterned neuromodulation of the spinal cord and cortex. This allows brain signals associated with movement intention to directly control the movement of the user's own hand in real time while also promoting long-term sensorimotor recovery-even after the system is turned off. The DNB system uses recurrent artificial neural networks and reinforcement learning for fine grasp control, together with patterned spinal cord stimulation and activity-informed intracortical microstimulation ('cortical mirroring') to promote neuroplasticity and durable recovery of function. In a participant with chronic C4 sensory/C5 motor complete tetraplegia, this hybrid approach enabled recovery of functional abilities including self-feeding and manipulation of delicate objects, while also producing significant and persistent improvements in elbow flexion and wrist tactile sensation. These findings demonstrate the potential of combining a sensorimotor neuroprosthesis with targeted brain and spinal neuromodulation to restore clinically relevant function in severe paralysis.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 42463883 · DOI · PMC13375563
Rapid personalized computational modeling of the wrist [3]
Abstract reading summary — source excerpts
- Opening excerpt
- Computational modeling may help to develop new treatments for hand and wrist injuries, but at present, few models exist, as the time and expertise required is considerable.
- Closing excerpt
- Lastly, to encourage reproducibility, we have made the data, models, and code publicly available online.
- Interpretation limits
- Verbatim excerpts from the authors’ abstract; the closing excerpt may describe a finding, limitation or recommendation. Design, population, effect size and uncertainty have not been independently extracted or appraised. Read the complete abstract and linked paper before interpreting the findings.
Read complete abstract (154 words)
Computational modeling may help to develop new treatments for hand and wrist injuries, but at present, few models exist, as the time and expertise required is considerable. Moreover, most models do not allow for variation of material properties. We have developed an automated workflow combining morphing with algorithmic techniques to create personalized finite element models. Using this workflow, three personalized models were created from our existing four-dimensional computed tomography data. These were then used to demonstrate the usefulness of these models to investigate clinical questions, namely calibration of ligament properties to participant-obtained kinematics, and Monte Carlo analysis of the impacts of ligament injury on joint contact pressure, as an analogue for joint injury that may lead to osteoarthritis. New models can be created in 2 h and individual simulations performed in 45 s. This work enables future patient-specific modeling. Lastly, to encourage reproducibility, we have made the data, models, and code publicly available online.
Abstract reproduced from the open-access article under the recorded cc by licence; © the authors. PMID 42392143 · DOI · PMC13465003
Key reviews and meta-analyses
The most cited review-type papers among PubMed’s best-match results for this heading, listed with bibliographic details only. Follow the links for the full text and access terms.
- Research article Incidence of unilateral arm lymphoedema after breast cancer: a systematic review and meta-analysis [4]
- Research article Interventions for improving upper limb function after stroke [5]
- Research article Effects of Robot-Assisted Therapy for the Upper Limb After Stroke [6]
- Research article Predictors of upper limb recovery after stroke: a systematic review and meta-analysis [7]
- Research article Effects of robot-assisted upper limb rehabilitation in stroke patients: a systematic review with meta-analysis [8]
- Research article Second to fourth digit length ratio (2D:4D) and adult sex hormone levels: new data and a meta-analytic review [9]
References
- Gür M, Akkoc RF, Oz B, Karatas A, Koca SS. The 2D:4D Digit Ratio and Primary Sjögren's Syndrome: A Window Into Prenatal Hormonal Influences on Exocrine Autoimmunity. . 2026. PMID 41958154 · DOI · PMC13066761
- Chandrasekaran S, Wandelt SK, Jangam A, Elias Z, Ibroci E, Maffei C, et al.. A neuroprosthesis for restoring hand movement and sensation in a person with complete tetraplegia. . 2026. PMID 42463883 · DOI · PMC13375563
- Andreassen TE, Trentadue TP, Thoreson AR, An KN, Kakar S, Zhao KD. Rapid personalized computational modeling of the wrist. . 2026. PMID 42392143 · DOI · PMC13465003
- DiSipio T, Rye S, Newman B, Hayes S. Incidence of unilateral arm lymphoedema after breast cancer: a systematic review and meta-analysis. Lancet Oncol. 2013. PMID 23540561 · DOI
- Pollock A, Farmer SE, Brady MC, Langhorne P, Mead GE, Mehrholz J, et al.. Interventions for improving upper limb function after stroke. Cochrane Database Syst Rev. 2014. PMID 25387001 · DOI · PMC6469541
- Veerbeek JM, Langbroek-Amersfoort AC, van Wegen EE, Meskers CG, Kwakkel G. Effects of Robot-Assisted Therapy for the Upper Limb After Stroke. Neurorehabil Neural Repair. 2017. PMID 27597165 · DOI
- Coupar F, Pollock A, Rowe P, Weir C, Langhorne P. Predictors of upper limb recovery after stroke: a systematic review and meta-analysis. Clin Rehabil. 2012. PMID 22023891 · DOI
- Bertani R, Melegari C, De Cola MC, Bramanti A, Bramanti P, Calabrò RS. Effects of robot-assisted upper limb rehabilitation in stroke patients: a systematic review with meta-analysis. Neurol Sci. 2017. PMID 28540536 · DOI
- Hönekopp J, Bartholdt L, Beier L, Liebert A. Second to fourth digit length ratio (2D:4D) and adult sex hormone levels: new data and a meta-analytic review. Psychoneuroendocrinology. 2007. PMID 17400395 · DOI
About this article
- Sources
- NLM Medical Subject Headings (definition, synonyms); NCBI PubMed (counts, identifiers); Europe PMC (open-access abstracts and citation counts).
- Verification
- Every reference was resolved against PubMed on 2026-10-31; title, year and DOI matched.
- Review state
- automated source verified; no human expert review has been recorded yet.
- Version
- 1, last updated 2026-10-31.
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Evidence strength
EvidenceHelix's computed view of the study designs behind this topic: how common meta-analyses, randomized trials and reviews are, how recent the literature is, and a plain-language reading. It describes the design mix of the literature. It is not a quality appraisal of any study, and it is not medical advice.