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Wonderful Orthopaedic, Trauma & Prosthetics

Wonderful 3F31

Product Code: OTAP-PLAC-2925

Supplied with its documentation, its history and its condition set out.

On a load-bearing component that has already been in service, what is known about the individual item matters alongside what the model can do. Inspection findings, service history and the manufacturer's documentation travel with the joint. Listed on Medigear.uk for UK business buyers.

Sections

Prosthetic Feet & Knees

Categories

Orthopaedic, Trauma & Prosthetics

Condition

New

Origin

China

Seller Type

Certified Professional Seller

CE & ISO Certified

Global Shipping

Supplier: Medigear

A linkage knee is a set of machined bars connected by pivot pins running in bushings or bearings. Every step a user takes cycles those pivots under load, and over a service life measured in millions of cycles the fit between pin and bushing is what changes.

That makes the pivots the natural focus when a component is being assessed. Play in the linkage is felt as looseness at the joint and shows as movement between bars that should be constrained, and it develops gradually rather than suddenly. Whether that play is within the manufacturer's tolerance, and whether pins and bushings can be replaced to restore it, are the two questions that decide whether a component has service life remaining. Both are answered from the manufacturer's service documentation and from a current inspection, and both should sit in writing before a purchase rather than after.

Surface condition carries information too. Machining marks, anodising or plating wear at contact points, and any distortion or scoring on a linkage bar tell a different story from cosmetic scratching on a housing. Structural marking on a load-bearing member is a matter for the manufacturer's guidance, and cosmetic marking is not the same thing.

Where a hydraulic or pneumatic unit is fitted, seal condition and any evidence of leakage are separate questions again, along with whether the unit is serviceable independently of the linkage or replaced as an assembly.

Alongside condition sits provenance. What the component carried in its previous fitting, in weight and activity level, is relevant to what remains of its rated life, and a joint that spent years under a high-activity user has a different history from one that saw limited use. Any refurbishment matters equally, including what was replaced, by whom, and against what specification.

None of this displaces the ordinary specification. Load rating and indicated mobility grade decide suitability for the individual, component weight and build heights define the envelope between socket and foot, and the proximal and distal interfaces determine compatibility with the adaptors, tube and foot already chosen. In a polycentric knee the effective centre of rotation sits away from any physical pivot and moves through flexion, so stance stability and swing clearance are both served by the geometry of the linkage.

This is a component rather than a finished prosthesis. It is fitted, aligned and adjusted by a qualified prosthetist as part of a limb assembled around the individual, and selection, alignment, settings and suitability for a given patient are clinical decisions taken by that professional, who will also form a view on whether a used component is appropriate for a given fitting. The manufacturer, condition, service history, load rating, mobility grade, indicated amputation levels, build heights and connection types are provided by the seller at quotation, with UKCA or CE marking documentation, the declaration of conformity, instructions for use and warranty terms issued by the manufacturer or held by the seller.

Transfemoral prosthetic fitting is the primary application, with the joint supplied as a component for a prosthetist to align and adjust within a complete limb.

Services considering pre-owned components are supported by inspection findings and service history supplied in writing alongside the manufacturer's documentation.

Knee disarticulation and long residual limb fittings are where linkage geometry is commonly specified, since space below the socket is limited.

Suitability for a given patient follows the load rating and indicated mobility grade, both taken from the manufacturer's instructions for use.

Stance stability and swing clearance are both served by the linkage geometry, with the specific behaviour established from the manufacturer's documentation.

Clinics maintaining a component stock benefit from provenance and refurbishment records held against each item.

Services planning maintenance are supported by establishing replacement pin and bushing availability before a component enters stock.

Condition Reported in Writing

Inspection findings on the linkage, pivots and surfaces are supplied with the component rather than left to be discovered.

Provenance Supplied With the Item

What the component carried in weight and activity level, and for how long, forms part of what is known about it.

Refurbishment Recorded

What was replaced, by whom and against what specification is set out by the seller.

Serviceability Established Before Order

Replacement pin and bushing availability determines whether pivot fit can be restored across a longer service life.

Structural and Cosmetic Marking Distinguished

Marking on a load-bearing linkage bar and marking on a housing are assessed as separate questions.

Fluid Unit Assessed Separately

Where one is fitted, seal condition and independent serviceability are established alongside the linkage.

Geometry Serving Both Gait Phases

In a polycentric knee the effective centre of rotation moves through flexion, serving stance stability and swing clearance together.

Suited to Limited Build Height

Linkage geometry is commonly specified where space below the socket is short.

Load Rating Taken From the Instructions for Use

The maximum patient weight is established from the manufacturer's documentation rather than from any listing.

Clinical Decisions Left With the Clinician

Whether a used component suits a given fitting is a judgement for the prescribing prosthetist.

Supply and Documentation Arranged

Medigear.uk can arrange supply, documentation and the provision of spares and consumables.

Modular Polycentric Knee Joint

A linkage mechanism placing the effective centre of rotation away from any physical pivot.

Item Reference: 3F31

To be confirmed against the manufacturer's marking on the component.

Condition Grade and Inspection Findings

Provided by the seller at quotation.

Service and Refurbishment History

Provided by the seller at quotation, including what was replaced and by whom.

Linkage Play and Pivot Condition

Assessed against the manufacturer's tolerance and reported at quotation.

Replacement Pin and Bushing Availability

Determining whether pivot fit can be restored, confirmed at quotation.

Linkage Construction

Number of bars and pivot axes confirmed at quotation.

Swing and Stance Phase Control Type

Mechanical, pneumatic or hydraulic, confirmed at quotation.

Maximum Patient Weight

Confirmed at quotation against the manufacturer's instructions for use.

Mobility Grade and Indicated Amputation Levels

Confirmed at quotation against the manufacturer's instructions for use.

Maximum Knee Flexion

Confirmed at quotation.

Component Weight, Structural Height and System Height

Confirmed at quotation for limb build calculations.

Proximal and Distal Connections

Types and diameters confirmed at quotation for compatibility with the build.

Materials, Finish and Bearing Type

Confirmed at quotation.

Water Exposure Rating

Confirmed at quotation, with conditions of use taken from the instructions.

UKCA or CE Marking and Declaration of Conformity

Issued by the manufacturer and requested from the seller at quotation.

Instructions for Use

Provided by the seller at quotation, and required before fitting.

Warranty Terms

Set by the seller at quotation.

The 3F31 is a modular polycentric prosthetic knee joint supplied as a component to be built into a limb around one person. A linkage knee is a set of machined bars connected by pivot pins running in bushings, and every step cycles those pivots under load, so across a service life measured in millions of cycles it is the fit between pin and bushing that changes. That makes the pivots the focus of any assessment: whether play in the linkage sits within the manufacturer's tolerance, and whether pins and bushings can be replaced to restore it, together decide how much service life remains. Surface condition, seal condition where a fluid unit is fitted, and provenance in weight and activity level carried all add to that picture, and refurbishment records complete it. Alongside condition sit the ordinary questions of load rating, mobility grade, build envelope and connection compatibility, while the linkage geometry serves stance stability and swing clearance together. Whether a used component suits a particular fitting remains a judgement for the prescribing prosthetist. The manufacturer, condition, service history, ratings, build heights and connection types are provided by the seller at quotation, alongside UKCA or CE documentation and instructions for use. Medigear.uk lists the joint for UK business buyers and can arrange supply, documentation and the provision of spares and consumables. Enquire for a written quotation.

FAQ

Frequently Asked Questions

Everything buyers need to know about sourcing medical equipment through MediGear.

It is a modular polycentric prosthetic knee joint supplied as a component for a prosthetist to fit within an above-knee prosthesis. The construction, ratings and condition are set out at quotation.

The pivot pins and their bushings or bearings, which cycle under load with every step and develop play gradually over a long service life.

By measuring play in the linkage against the manufacturer's tolerance and inspecting the pivots, with the findings reported in writing.

Where replacement pins and bushings are available and the manufacturer's service documentation permits it, the fit can be restored. Availability is confirmed at quotation.

Cosmetic marking on a housing and structural marking on a load-bearing linkage bar are different questions, and the manufacturer's guidance governs the latter.

Seal condition, any evidence of leakage and whether the unit is serviceable separately from the linkage are established at quotation.

The weight and activity level a component carried bear on what remains of its rated life, so provenance is part of the assessment.

What was replaced, by whom and against what specification, all of which is provided by the seller.

Confirmed at quotation against the manufacturer's instructions for use, which is the only source that should be relied on for a load-bearing component.

The effective centre of rotation sits away from any physical pivot and moves through flexion, serving stance stability and swing clearance through geometry.

The prescribing prosthetist, who forms that view alongside the manufacturer's guidance and the inspection findings supplied.