The STEMLESS version of the UNIC system is indicated for hemi or total degenerative or trauma shoulder arthroplasty where the rotator cuff is intact or repairable.
The metaphysealcementless fixation of the STEMLESS UNIC helps preserving the integrity of the intra-medullar humerux.
The UNIC STEMLESS implant is made with additive technology. This 3D metal printing technology enabled the design of a very fine honeycomb structure adapted in porosity and interconnectivity to the osteoblastic activity. The bone integration is facilitated by a layer of Hydroxyapatite coating on all the surfaces in contact with the bone.
The instrument set enables the placement of the prosthetic humeral head, selected from a choice of 8 diameters (35mm to 52mm) and 2 thicknesses begining diameter 41, in complete respect of the intra-articular space for retroversion, lateralization, varization…)
HEMI OR TOTAL ARTHROPLASTY
The UNIC STEMLESS implant can be used alone or in association with the cemented glenoid implant of the standard UNIC range.
The anatomic glenoid implant is only available in cmeneted full polyethylene version. Available in 3 sizes, the glenoid implant can be combined to any STEMLESS size with a mean mismatch of 2mm.
Hemi-arthroplasty head with increased volume indicated in Cuff Tear Arthroplasty cases.
Whenever the glenoid bone highly worn out does not allow proper fixation of a glenoid base.
The increased volume/thickness of the CTA head enables the prosthesis to articulate with the sub-acromial surface.
A supero-lateral “cap” extends the articualr surface and prevents the rotator cuff from rubbing on the resected bone.
The “bilboquet” (cup-and-ball game) concept was imagined in 1989 in the concern to improve the stability and the ease of the anatomical reconstruction in the complex and displaced fractures of the superior extremity of the humerus (FSEH).
Such 3 or 4 fragments fractures on osteoporotic bone are characterized by the difficulty of maintaining the stability of the osteosynthesis and by the exposure to complications like avascular osteonecrosis of the humeral head.
The “bilboquet” concept is based on the implementation of a circular staple impacted in the cancellous bone of the humeral head, the staple so constitutes a solid platform which allows to support circumferentially the head and to reduce it anatomically.
The “JUST UNIC” shoulder fracture device brings to this concept a major innovation by differentiating the stability of the device in the huméral blunderbuss via the implementation of the “sleeve”, and the regulation in height of the humeral stem. Tjis innovation allows to facilitate the reduction and to maintain the space of reintegration of the tuberosities.
The preservation of the humeral head in contact with the tuberosities favors the consolidation of the fracture (1 ). Based on this principle, for the cases where the secondary osteonecrosis is a risk, the “JUST UNIC” system proposes an option of hollowed head hollow which allows to graft the osseous head in contact with the tuberosities, leading to the same principle that the “bilboquet” staple.
Humeral base adapted to the osteosynthesis of multiple fragment fractures of the proximal humerus.
The UNIC Trauma stem has the same characteristics as all the humeral bases of the UNIC system.
All the articular combinations of the UNIC system are adaptable to the UNIC “Trauma” base: hemi-arthroplasty, anatomic, reverse and CTA.
The instrumentation is the basic “2 trays” UNIC set: 1st tray is for the humeral preparation and for the reverse glenoid, 2nd tray is for the other articular options.
Indicated for fracture of the humeral epiphysis in the elderly.
The anatomic total shoulder arthroplasty (TSA) is indicated when both sides of the scapulo-humeral joint are worn out, and when the rotator cuff remains intact and with no sign of motricity defficiency. The TSA requires a good glenoid bone stock, and will be contra-indicated whenever there pre-exist a permanent instability in the joint.
The UNIC anatomic system is characterized by:
- Compatible with all and any humeral base: primary, fracture or revision, cemented or cementless
- Oval humeral heads available in 5 combinations of diameter/thickness
- Efficient multi-position Head offset management based on twin crossed ratchets and twin taper modulus
- Optionnal 6° angled modulus to fine tune for increased varus/valgus or ante/retroversion
- Identical mismatch through the range unabling match of all heads with all sizes of glenoid
- Low 2mm mismatch reduces sheer stresses on the glenoid component
The reverse total shoulder (TSR) is indicated when both sides of the shoulder joint are worn out and associated to an extended and irreparable lesion of the rotator cuff. In this indication, the glenoid bone stock must allow the fixation of a prosthetic glenoid base.
The UNIC system is characterized by:
- An orientation of the humeral cup increased by 8° compared to the humeral resection cut
- A reduced cup diameter to sphere diameter ratio
- A multiple position fine tuning of the cup on the stem unabling proper arm lateralization and deltoid muscle tension
- A glenoid base bone anchoring based on an helical non-traumatic blade which is designed to resist sheer stresses
UNIC is a prosthetic modular system which unables, on the basis of a same humeral platform – primary, fracture or revision- to achieve either a CTA hemi, an anatomic total shoulder, or a reverse total shoulder arthroplasty.
HUMERAL PLATFORMS TO SUIT ANY PROSTHETIC SHOULDER INDICATIONS
Any type of UNIC humeral stem is a platform on which the surgeon can plan and build up to suit any indication:
- cementless HA coated or shiny-polished cemented primary stems
- slotted or distal locked cementless HA coated, or shiny-polished cemented revision stems
- fracture stem soon available
- very small sizes both primary and revision available on special request