MiniMix

Mixing of 40g* or less of PMMA bone cement or bone substitute materials
*(20g Simplex,^®)

• Hip Resurfacing
• Unicondular knees
• Vertebroplasty
• Bone void filling
• Small joints

• Patented geared rotational axis mixing mechanism
  Ensures a reproducibly high quality mix, significantly better than fixed axis or hand mixing – see Figure 1.
• Unique material transfer valve
  Allows the mixed material to be cleanly and precisely transferred into the delivery device or prosthesis.
• 8mm open bore or Luer Lock transfer interface options
  8mm open bore allows the mixed material to be easily transferred into hip resurfacing femoral components. Luer lock interface allows transfer of the material into standard syringes of varying sizes.
• Vacuum level of 550mmHg
  Allows PMMA cement to be mixed at optimal levels of porosity to maximise the mechanical properties of the cement.
• Charcoal / microbiological filter
  Reduces MMA fumes in theatre to levels significantly below those set out in the Health and Safety Executive guidelines.
• Latex free product
  Provides protection against potential latex allergy for nursing staff and patients.
• PVC free packaging
  Helps minimise environmental pollution.
• Few components / simple to use design

The specific aim of the MiniMix™ systems are to ensure not only a homogenous, reproducible mix, but importantly for the user a quick and effective transfer of the material into a delivery device or prosthesis. The design allows for effective mixing of either bone cements or bone substitute materials meeting the needs of Orthopaedic Surgeons and Interventional Radiologists.

Mixer design has been found to significantly influence the quality of cement [1], Figure 1.

This paper shows significantly better PMMA mix quality from a rotational axis device compared to that created by hand mixing or a fixed axis system. The Summit Medical MiniMix™ design includes a rotational axis mechanism to reduce unmixed powder.

To further enhance the strength of bone cement, it needs to be mixed under optimal vacuum levels. If the vacuum level is too low then the cement will contain high levels of porosity, but if too high, excessive thermal shrinkage can create cracking in the cement mantle, Figure 2. The Summit Medical MiniMix™ has a vacuum option functioning at 550mmHg, which has been proven to provide an optimal balance between the two.

Exposure to methylmethacrylate (MMA) fumes is a concern of many people who work in the vicinity of bone cement mixing. Health and Safety Executive (HSE) guidelines recommend a maximum exposure for these fumes of 100ppm during a 15-minute period [2]. The Summit Medical MiniMix™ includes the option of a lineset with an integral filter, which reduces fume levels to a small fraction of these guideline limits. Figure 3 shows how the same filter system on the Summit HiVac™ Bowl maintains fume levels below the 15-minute exposure guideline of 100ppm.

1. Kurdy NMG, Hodgkinson JP and Haynes R, 1996. Acrylic bone-cement; influence of mixer design and unmixed powder. J Arthroplasty, 11 (7). 813-819

2. Cary R, Morris L, Cocker J, Groves J and Ogunbiyi A, 1995. Methylmethacrylate: Criteria Document for an occupational exposure limit. Health and Safety Executive.

For further information and details of availability of these products by country please contact: info@summit-medical.co.uk