System description

Both the Mini Fragment and Small Fragment Plating Systems  are intended for adults, children (2–12 years), and adolescents (12–21 years) in which growth plates (physes) have fused, or in which unfused growth plates will not be compromised by fixation.

The indication is such that the plating systems support auxiliary plating techniques and education.  Instructions for use and surgical technique are available from Johnson & Johnson MedTech with details of indications, contraindications, side effects, warnings, and precautions.

The new plates are designed to offer various options regarding plate shape and profile as well as hole density appropriate to different fracture patterns. The instrument functionality has been improved and a consistent look and feel has been implemented to ensure ease of use.

The Mini Fragment and Small Fragment Plating Systems are designed in a modular way, to be assembled according to customers’ preferences. Color-coded universal and size-specific instrument and implant trays support the surgeon and the tech staff in choosing the right instruments for the selected plates.

VOLT locking technology

A key innovation of the VOLT platform is the novel variable angle locking technology (Figs 6-7). The VOLT holes appear round but actually have a subtle triangular shape with threads that are precisely engineered with tight manufacturing tolerances. The unique shape of the VOLT holes enables the plate threads to adapt to the screw threads as the screw is inserted. The result is excellent plate to screw engagement and robust cantilever strength. The technology allows for a screw angulation of up to 15°, hence a locking cone of 30°.

The cantilever strength of a VOLT plate/screw (2.4 mm, 2.7 mm, 3.5 mm) interface at nominal (0°) is equivalent to the LCP plate/screw interface at nominal (0°), yet VOLT delivers variable angle capability (Static Cantilever Strength; Fig 8). Thus, the VOLT technology combines the advantages of an LCP with the option of variable angle locking technology. Also, the new combi holes benefit from the VOLT locking technology in the locking part of the combi hole.

All VOLT hole types accept the use of either locking or cortex and cancellous  screws. Accordingly, the same fixation principles apply as with previous LCP and VA-LCP systems, facilitating education and transition to VOLT.

Screws

A combination of locking, cortex, and cancellous screws offers versatile options tailored to the VOLT plates. To streamline the surgical steps, instruments are color-coded according to screw diameter. Additionally, a single- or double-band etching assists in identifying complementary parts.

Screws, equipped with an optimized Stardrive recess design (Fig 9), along with new screwdrivers, are intended to enhance the user experience. In addition to the optimized recess design, cortical and cancellous screws have lower profile heads compared to previous designs due to soft-tissue considerations.

The locking screws are designed for locking performance, while offering cutting flutes for ease of insertion and a rounded screw tip (Fig 9), both designed to reduce the risk of soft-tissue irritation.

In the VOLT Small Fragment system, the 4.0 mm cancellous screw offers better hold in the bone compared to the 3.5 mm cortical screw and remains an important fixation option in epi-metaphyseal zones. To support removal, the cancellous shaft screw features back-cutting flutes.

The system offers longer screws compared to its predecessor, providing greater versatility (2.0 mm: up to 50 mm; 2.4 mm and 2.7 mm: up to 90 mm; 3.5 mm: up to 110 mm).

Plates

The VOLT Mini and Small Fragment Plating Systems feature a wide range of generic plates (Figs 1-2) . Generic plates, also called non-anatomic or utility plates, are a key pillar in trauma surgery due to their adaptability and versatile application as primary fixation or as an auxiliary fixation device to other implants. All new generic plates feature VOLT technology (Fig 10a-c).

Several new plate shapes and lengths have been introduced. Design features on the plates such as rounded profiles and tapered tips are beneficial as they respect soft tissue and can be used in less invasive surgical techniques. VOLT plate shapes and screw hole patterns are intended to optimize plate function, whether for locking, compression, or buttressing, ensuring efficacy and stability in various orthopedic applications. Furthermore, plate options with increased screw hole density are available, offering more fixation options and thereby providing surgeons with greater flexibility and precision to meet daily fracture fixation challenges.

VOLT titanium plates and screws are anodized and then treated with an electropolish finish. Electropolishing the titanium plates and screws produces a surface texture (Fig 10d) similar to stainless steel. This smooth surface finish reduces bony ongrowth and soft-tissue adhesion, which has been shown to ease implant removal.

Plate types and features

Straight plates

Straight plates (Fig 11) are available for all sizes and are optimized for strength. The proven plate undercuts from LC-DCP and LCP are maintained to give the plate a widely uniform stiffness, supporting continuous bending while limiting contact with the bone when applied with non-locking screws (Fig 11a). While keeping the rounded, smooth tip to support less invasive insertion, holes are also placed close to the ends of the plate, offering a wide fixation range (Fig 11b). Two K-wire holes give an additional option for temporary fixation. The 2.0 mm, 2.4 mm, and 2.7 mm plates are also available in a compact version.

Mini Fragment generic plates

Adaption plates

Adaption plates (Fig 12a) offer the surgeon greater freedom to adapt the plate to specific anatomical situations. Accordingly, they are optimized to allow in-plane, out-of-plane, and torsional bending and cutting to trim the plate to the length needed. Additional focus was given to producing a low and smooth plate profile as these plates are often used in soft-tissue critical zones. Depending on the adaption plate type, the plates offer the VOLT hole, combi hole, elongated combi hole. or a combination thereof. Adaption plates were developed for sizes 2.0 mm, 2.4 mm, and 2.7 mm.

Straight adaption plates

These plates are available with a combi hole and in a compact version (Fig 12b-c). The plates are offered in a length of up to 20 holes.

Condylar, Y, and T plates

These plates feature a head element (Fig 13a-d) and are suited for fracture situations where additional fixation options are required.

Hook plates

The hook plate’s adaptability and sharp hooks (Fig 13e) allow the plate to grab and hold small fracture fragments close to a joint and compress them to the shaft. A recess between the hooks supports the secure placement of a cortical screw if needed.

Triangle plates

The triangle plate (Fig 14a) is designed to offer a broader buttressing surface with multiple fixation options. Therefore, the plate has a triangular head shape.

Tine plates

The tine plate (Fig 14b) was developed to give a broader buttress surface and to offer additional support to hold small fragments. Therefore, the plate features a two-hole wide head and two tines that grab the bone (Fig 14c).

Small Fragment generic plates

Metaphyseal plate 3.5 mm

The long taper at the tip of the metaphyseal plate 3.5 mm (Fig 15a) supports buttressing techniques and plate adaption to different anatomies as well as having a low prominence (Fig 15b) considering the often delicate soft-tissue situation. There are three VOLT holes that have an initial screw trajectory of 7° that accommodate plate bending to avoid the joint surface. The longer plates also contain two elongated holes in case of fractures extending into the shaft. The shaft of the plate otherwise offers the same characteristics as the straight small fragment plate.

T plate 3.5 mm

The VOLT T-Plate (Fig 15c) is a thin flat plate, intended mainly for buttressing applications in multiple different indications. The plate is offered with a 4- and 3-hole T section. Frequently used close to joints, the plate is designed with K-wire holes with undercuts to facilitate suturing (Fig 15d).

Reconstruction plate

The versatile reconstruction plate (Fig 16a-b) is designed for situations where bending in different planes is required. It is therefore optimized for in- and out-of-plane bending and for torsional bending, while broadly keeping hole functionality.

1/3 Tubular plate

The 1/3 tubular plate (Fig 16c) maintains its position as a key implant in today’s surgery. Of critical importance was the integration of VOLT technology to incorporate the advantages of VA locking fixation into the plate, while maintaining the elastic properties and thinness of current plates.