Child’s 4-Bar Knee

Suitable for outdoor use
Activity Level 1 2 3 4

Featuring a polycentric design for stability during stance and an adjustable extension assist spring to provide swing control, the Child’s 4-bar Knee is a durable and lightweight paediatric knee designed for active children.

Available with a choice of proximal adapters including a Standard Socket Alignment Kit allowing for A-P shift, rotation and flexion, extension, adduction and abduction. A Lamination Socket Adapter Kit allows for A-P shift and is ideal where a minimal build height is required. All alignment adjustments can be made using the easily accessed single bolt.

The knee comes complete with a 25mm lightweight carbon fibre tube and 3 different extension springs for optimal fitting.

Key Features

  • Polycentric knee for stance stability
  • Adjustable extension assist spring
  • Wide range of alignment
  • Low build height

Child’s 4-Bar Knee Clinical Evidence Reference

Improvements in Clinical Outcomes using four-bar, polycentric knees compared to monoaxial knees

  • Increased mean prosthetic minimum toe clearance2,4, reducing the likelihood of tripping.
  • Fully satisfies stance phase stability3
  • Acceptable cosmetics for knee disarticulation amputees and trans-femoral amputees with long residua1
  • Meets all the design requirements for paediatric patients3


1. de Laat FA, van Kuijk AA, Geertzen JH, et al. Cosmetic effect of knee joint in a knee disarticulation prosthesis. J Rehabil Res Dev 2014; 51: 1545.
2. Sensinger JW, Intawachirarat N, Gard SA. Contribution of prosthetic knee and ankle mechanisms to swing-phase foot clearance. IEEE Trans Neural Syst Rehabil Eng 2012; 21: 74–80.
3. Andrysek J, Naumann S, Cleghorn WL. Design characteristics of pediatric prosthetic knees. IEEE Trans Neural Syst Rehabil Eng 2004; 12: 369–378.
4. Gard SA, Childress DS, Uellendahl JE. The influence of four-bar linkage knees on prosthetic swing-phase floor clearance. JPO J Prosthet Orthot 1996; 8: 34–40.

See all the Clinical Evidence for every Blatchford product in our Clinical Evidence Finder Tool.

Child’s 4-Bar Knee Technical Data

Max. User Weight:


Activity Level:


Component Weight:


Build Height:



Proximal Adapters

Child’s TF alignment kit 189226
Lamination Socket Alignment Kit 189126
M30 Laminate Adapter 4 Prong Kit 189626
M30 Childs Adapter Kit 189726
Female Mini Pyramid Pylon Kit 25mm 409099



Part Number: 

Child’s 4-bar Knee with 330mm tube 019245
Child’s 4-bar Knee without tube 239133

Child’s 4-Bar Knee Documentation

Product Information

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