Scoping Review · Robotic Knee Arthroplasty

Use of the VELYS Robotic-Assisted Solution in knee arthroplasty: A scoping review

A scoping review conducted in accordance with the PRISMA-ScR framework

Morrison SR, Hall AJ, Clement ND, Walmsley PJ, Gee C, Clarke JV

J Exp Orthop 2026;13(2):e70726 · doi:10.1002/jeo2.70726

Included Studies

Randomised Controlled Trials

II–IV

Range of Evidence Levels

64%

Studies With Industry Conflict

As Published Journal of Experimental Orthopaedics, Volume 13, Number 2, April 2026 cover

European Society of Sports Traumatology, Knee Surgery & Arthroscopy (ESSKA)

This scoping review was published as a Review Paper in the Journal of Experimental Orthopaedics (JEO), the official fully open access journal of ESSKA. It maps the current evidence for the VELYS Robotic-Assisted Solution in total knee arthroplasty, one of six platforms named in the NICE early value assessment of robot-assisted orthopaedic surgery.

Journal J Exp Orthop

Article Type Review Paper

Licence CC BY 4.0

Access Open Access

Read on wiley.com Download PDF

Abstract

Purpose

Robotic knee arthroplasty has been associated with improved knee-specific outcomes, but results are relatively immature. The VELYS Robotic-Assisted Solution is an imageless semi-active system used with the ATTUNE knee arthroplasty system. Following a call from the UK National Institute for Health and Care Excellence (NICE) for a multidomain evaluation of six robotic-surgery platforms, this review aimed to evaluate current evidence on VELYS in total knee arthroplasty, assess outcomes, complications, cost and versatility, appraise study quality, and identify knowledge gaps.

Methods

A scoping review using five-stage methodology following the PRISMA extension for Scoping Reviews (PRISMA-ScR) was undertaken. Articles were screened against pre-determined criteria, with data synthesised descriptively and thematically.

Results

Twenty-five studies were included, with evidence levels ranging from II to IV. Analysis highlighted improved implant positioning as seen with other robotic systems, alongside a non-inferior safety profile. However, despite studies appearing to show favourable early patient-reported outcomes, function and workflow efficiency, the overall quality of the published work was poor, giving little evidence to robustly support many of the conclusions drawn. Limitations included small sample sizes, limited information on patient characteristics and selection, retrospective design, and a lack of long-term follow-up.

Conclusion

The available literature on the VELYS Robotic-Assisted Solution is limited and of moderate-to-poor quality. Implant positioning was more accurate; however, other results, especially regarding improved patient outcomes, are not currently well-evidenced. Evidence was largely retrospective or early prospective, with no randomised controlled trials or long-term data. High-quality, randomised studies are required to evidence this technology.

Search & Selection

PRISMA-ScR screening process

156

Records identified across databases

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114

Screened after duplicates removed

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Full-text articles assessed

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Studies included (0 excluded at full text)

89 records were excluded at screening, most commonly for not being specific to VELYS (n=31), lacking objective data or empirical findings (n=22), or relating to hip arthroplasty (n=19). Two further studies were identified through expert recommendation. No articles were excluded at full-text review.

Thematic Analysis

Six key themes

Implant Position & Alignmentn=11 studies

Cadaveric and in-vivo studies consistently found VELYS produced more accurate implant positioning with fewer alignment outliers than manual instrumentation.

Where differences reached statistical significance, the magnitude was often small, and may not translate into a benefit that is meaningful to patients.

Most studies were small, single-centre and involved early adopters, limiting how far the findings generalise.

Clinical Outcomes & PROMsn=12 studies

There was broad agreement of no relevant difference in complication, infection or acute revision rates compared with manual arthroplasty.

Some studies reported better early pain and function scores, but differences between groups were generally small and many comparisons were not significant.

Findings were caveated by small samples, ceiling effects in existing PROMs, and an absence of long-term outcome data.

Surgical Efficiency & Workflown=14 studies

Total operating room time was generally increased relative to manual cases, with reported increases ranging from around 4 to 23 minutes.

This effect appeared to lessen as teams gained familiarity, with learning curves reported at roughly five to eleven cases across studies.

Learning-curve studies used surgical time as a surrogate for proficiency, which does not capture the quality or safety of procedures.

Safety & Complication Profilen=9 studies

Comparative studies demonstrated no evidence of additional harm associated with VELYS, and some suggested fewer adverse events.

An FDA adverse-events database review implicated VELYS in 159 of 839 reported events, most commonly mechanical failure and inappropriate bone resection, though reporting limitations make these difficult to interpret.

Available safety data covered only the intraoperative and early postoperative period.

Soft Tissue & Bone Preservationn=4 studies

Studies suggested VELYS may reduce the need for soft-tissue releases to achieve a balanced knee.

Whether this benefit is attributable to the device specifically, rather than to a functional alignment strategy in general, is not clear.

Surrogate measures such as polyethylene liner thickness are of limited value as markers of quality.

Versatility & Complex Casesn=3 studies

A small number of studies reported encouraging correction of severe deformity and extra-articular cases using VELYS.

These were limited by small samples, varied methodology and case-series design.

They add real-world context but cannot support firm conclusions on complex-case benefit.

Research Priorities

Knowledge gaps and research priorities

Safety and implant survivorship need long-term monitoring

Longer-term longitudinal and registry studies are needed to review adverse events and revision rates, with registries tracking not only that a robotic device was used but the specific manufacturer.

Clinical benefit requires robust, controlled comparison

Controlled comparative studies, powered to detect important differences in outcomes and adverse events, should compare VELYS against manual surgery and other robotic systems, with subgroup analysis across knee-deformity phenotypes.

Functional outcomes need well-powered, ideally randomised study

High-quality functional evaluations, using randomised controlled trials where possible and objective measures such as motion analysis, are required to move beyond PROMs that are subject to ceiling effects.

Economic and efficiency impact is poorly characterised

Robust micro- and macro-economic analysis is needed to understand the true cost-benefit of the technology, including time in theatre, surgical team workload and learning-curve effects across the whole patient journey.

Take-Home Messages

VELYS improves the accuracy of implant positioning, consistent with other robotic systems, and shows a non-inferior early safety profile.

Claims of improved patient outcomes, function and efficiency are not yet well-evidenced: the literature is largely retrospective, of moderate-to-poor quality, and heavily influenced by the device manufacturer.

High-quality, randomised studies with long-term follow-up are required before the value of this technology for routine practice can be confirmed.

Use of the VELYS Robotic-Assisted Solution in knee arthroplasty: A scoping review

PRISMA-ScR screening process

Six key themes

The evidence base, and its conflicts

Knowledge gaps and research priorities