The Natural fit

CONCEPT
THE NATURAL FIT

The philosophy of anatomical stems was introduced into the market during the 1980's with the aim to obtain the best press-fit in the metaphyseal femur using a design following the natural geometry of the proximal femur. The MiniMAX is an anatomical cementless stem engineered to provide the best fit and fill in the metaphyseal femur following the natural shape of the femoral canal. [1,2] The length of the stem and the shape have been studied size by size and have shown to be bone preserving and to provide good mechanical stability. [3]

WHY MiniMAX

  1. Minimal risk of impingement and fracture thanks to the lateral flare design

     
  2. Reduced risk of thigh pain thanks to the unique tip design

     
  3. Easy to introduce thanks to optimal stem curvature

     
  4. Metaphyseal fixation thanks to proximal Ti & HA coating

RADIOLOGICAL OUTCOMES [3]

TECHNICAL DATA

NECK

9° anteversion.
Mirror polished with 12/14 Eurocone taper.
Growing size by size to restore anatomy.

SHAPE

The best fit and fill in the metaphysis to restore physiological loads.
127° neck-shaft angle.

MACROSTRUCTURES

Negative medially and positive laterally:

  • Increasing the contact area.
  • Improving the mechanical stability.

LATERAL FLARE

Rounded and non invasive:

Providing minimal risk of impingement and fracture.
Making the insertion of the stem in the femoral canal easier.

TIP

Short and thin with 5° curvature and a distal optimisation:

  • Guiding the insertion into the femoral canal.
  • Avoiding distal interference reducing the risk of thigh pain.

MiniMAX is made of Titanium-Niobium alloy (Ti-6Al-7Nb).
The surface treatment consists of:

  • Ti coating, Ra 300μm, in the proximal 2/3 of the shaft to improve proximal fixation.
  • HA (Hydroxyapatite) coating, Ra 80μm, all along the shaft.

The HA coating has chemical characteristics similar to that of the human bone which stimulates the bony ongrowth [4,5,6,7].
When all of the HA coating is absorbed there is good interaction between stem and bone leading to long-term stability.

The MiniMAX stem is available in 9 sizes, from 0 to 8 in both left and right versions.

INSTRUMENTATION

ONE TRAY IS ENOUGH!

  • The trial neck fits onto the broaches for a quick and precise trial reduction.
  • Perfect dimensional correlation between broaches and prosthesis.
  • Offset broach handles available in left and right versions.
  • Special instrumentation available for AMIS (Anterior Minimally Invasive Surgery).
THE AMIS SYNERGY

REDEFINING THR: THE AMIS SYNERGY

The anterior approach, strengthened by several years of clinical experience, is the only technique which follows a path both intermuscular and internervous and therefore reduces considerably the risk of damaging periarticular structures such as muscles, tendons, vessels and nerves.
Thanks to its expertise, unique in the market, Medacta International is the worldwide leader for Anterior Minimally Invasive Surgery (AMIS) with worldwide learning centers to teach the surgical approach, permanent support for surgeons and continuous development of specific instrumentation.

With the use of MiniMAX you can enter the Medacta International AMIS world.

Discover:

  • The definitive MIS approach: AMIS;
  • Dedicated AMIS instrumentation;
  • The AMIS Mobile Leg Positioner: the original orthopaedic extension table included as part of the instrumentation that makes the surgery easier and reproducible;
  • The AMIS Education Program based on Medacta’s proven educational methods.

AMIS & MiniMAX

  • Thanks to its curved shape both in the sagittal and in the frontal planes, MiniMAX is easier to insert through a minimal access.
  • The length of the stem is ideal  for a minimally invasive approach.
  • The tip is useful to facilitate the insertion of the stem.
 
PUBLICATIONS

[1] Noble PC, Alexander JW et al. The Anatomical Basis of Femoral Component Design. Clin Orthop. 1988; 235: 146-65.
[2] Husmann O, Rubin PJ et al. Three-dimensional Morphology of the Proximal Femur. J Arthroplasty. 1997; 12(4): 444-50.
[3] Data on file: Medacta.
[4] Hardy et al. Bonding of Hydroxyapatite Coated Femoral Prostheses JBJS vol 73-B, No5, Sept. 1991.
[5] Hardy et al. Aspects Radiologiques de l’Arthroplastie Fémorale Revetue d’Hydroxyapatite et correspondence Histologiques Acta Orthop. Bel. Vol 59, Suppl I, 1993.
[6] Hardy et al. Projection d’Hydroxyapatite sur Prothèses Articulaires : Progrès ou Illusion ? Acta Orthop. Bel. Vol 59, Suppl I, 1993.
[7] Fraissinet P, Hardy D et al. Histological analysis of the bone-prosthesis interface after implantation in humans of prostheses coated with hydroxyapatite. The  journal of Orthop Surg. 1993; 7(3): 246-53.