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JUST ASM frmoral stem---TI+HA coating stem

Dec. 21, 2021

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ASM is an acronym derived from A Stem of Multi-FunctionIntended to provide a variety of combination of functionsProvides more flexibility for doctors in their surgical planning.



1.1 Indications

  • Developmental Dysplasia of the Hip(DDH)

  • Osteoarthritis of the hip

    • Primary degenerative osteoarthritis of the hip


1.2 Contraindication

  • osteoporosis

  • Severe stenosis of the medullary cavity

  • Severe femoral shaft atrophy does not provide reliable fixation of the revision prosthesis


2.1 product features

① Proximal triangular cuff design

lThe sleeve is conical and protrudes a triangle to one side, this design provides an oval locking on top of the sleeve, Thus the cuff can be tightly pressed and fixed in the epiphysis of the upper femur to provide rotational stability。

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② Taper locking of sleeve and handle body

lMorse taper connection relies on the mechanical friction force generated by the taper wall corresponding to the handle body and sleeve to achieve the effect of cold welding, so as to reduce the fretting of the base and effectively resist rotation


③ Distal spike design

The elongated lateral ridge design with eight protrusions at the distal end provides rotational stability of the femoral shaft

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Sleeve coating step design

lThe ring shear stress is changed into axial compressive stress, which improves the axial stability of the handle and prevents the handle from sinking 

lIncreased bone contact area with the proximal femur (13%), providing a wider integration interface and better osseointegration results 

lEffectively prevent debris from wear into the medullary cavity and reduce the possibility of osteolysis and loosening due to debris disease after surgery


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Sleeve Ti+HA double coating

lPlasma sprayed Ti coating features:High binding strength, good biocompatibility, no biological activity (No direct osseous binding with bone tissue) 

lPlasma sprayed HA coating features: good biological activity, but poor bonding strength with substrate titanium alloy 

lHA+Ti has high binding strength (The mismatch of thermal expansion coefficient between HA and matrix can be alleviated),Surface roughness, good biological activity 

lPlasma spraying has the advantages of fast coating formation, high temperature to completely dissolve HA, high bonding strength, low porosity, low residual stress and high coating quality


Sleeve and handle body separate assembly

lFor example, the length of lower limbs can be adjusted through the head-neck taper connection, and the femoral anteversion Angle can be adjusted through the neck-stem taper connectionAdjustable by 360° rotation

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3. case share


case 1

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case 2



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