Implant and Method for Covering Large-Scale Bone Defects for Thorax A Plastic Lattice That Rebuilds a Chest Wall

This patent describes an implant made largely of plastic, built as a lattice of ring elements joined by bridges, used to bridge large holes in the bony chest wall after surgery or trauma. It comes from Karl Leibinger Asset Management, part of the German KLS Martin Group, a surgical instrument and implant maker founded in 1896.

The Problem

When a large section of the rib cage has to be removed, most often to take out a tumour, or is destroyed by trauma, the surgeon is left with a gap in a structure that does two critical jobs: it protects the heart and lungs, and it moves with every breath. A defect of any size leaves the organs underneath exposed and can produce a flail segment, where part of the chest wall moves paradoxically during breathing. Covering the defect means bridging it, providing a connection between the bone portions still in the patient’s body.

The existing options each have drawbacks. Kirschner wires, thin metal pins used in K-wire osteosynthesis, are simple but the specification notes the approach is improvable with respect to stiffness. Metal rails and rib osteosynthesis plates provide more support but can be prone to movement after implantation. Metal in general brings its own difficulties in the chest: it is far stiffer than bone, which can cause stress at the fixation points, and it interferes with the CT imaging that patients recovering from a chest wall tumour resection will be having regularly.

What This Invention Does

The implant is built as a lattice structure rather than a solid plate. Each lattice cell comprises one or more ring elements, and each ring element includes a through-hole configured to receive a fixation device such as a screw. The rings of each lattice cell are connected to one another by linear or non-linear bridge elements, and the implant is made at least predominantly from a plastic material.

That combination gives a surgeon something a solid metal plate cannot. Because fixation points are distributed across every ring in the lattice, the implant can be screwed to whichever fragments of bone remain, in whatever positions they happen to sit, rather than requiring the anatomy to match a predetermined hole pattern. The bridges between rings, which may be straight or curved, define how the structure flexes, so the implant can be tuned closer to the stiffness of the chest wall it replaces instead of being far more rigid than the surrounding bone. Being predominantly plastic also means it is more compatible with follow-up imaging than a metal construct. The claimed method covers fixing the implant to at least two portions of a patient’s bone using the fixation devices.

Key Features

• Lattice construction. The implant is built from lattice cells rather than as a solid plate.
• Ring elements with through-holes. Each ring element carries a through-hole for receiving a fixation screw or similar device.
• Bridge elements. Linear or non-linear bridges connect the ring elements, setting the structure’s flexibility.
• Predominantly plastic. The implant is made at least mostly from plastic rather than metal.
• Distributed fixation. Fixation to at least two remaining bone portions can be made at whichever ring positions suit the anatomy.
• Large defect coverage. The design targets large-scale bone defects, particularly in the thorax.

Who Is Behind It

The applicant is Karl Leibinger Asset Management GmbH & Co. KG, a holding entity within the KLS Martin Group, whose site at Mühlheim an der Donau in Germany dates to 1896 and focuses its research and development on implants and surgical lights. The named inventors are Adem Aksu, Vanessa Klein and Frank Reinauer. The application is a divisional of Australian application 2024203321, filed 20 May 2024, with priority from June 2023.

Why It Matters

Chest wall reconstruction is uncommon compared with hip or knee surgery, but it is high-stakes: the patients are typically recovering from cancer resection or major trauma, and the reconstruction has to hold for the rest of their lives while flexing with every breath. Implants that better match the mechanics of natural bone, and that do not obscure the scans used to check for recurrence, address two of the real frustrations surgeons report with metal constructs. Australia’s thoracic surgery units use imported implant systems almost exclusively, so patent filings here reflect suppliers protecting their route into that market. Any such implant would need Therapeutic Goods Administration inclusion before it could be supplied in Australia.

Related Concepts

• Rib cage – the anatomy the implant reconstructs.
• Internal fixation – the surgical technique the implant belongs to.
• Implant (medicine)) – the device class and its regulatory context.
• Lattice) – the repeating cell geometry underpinning the design.
• Biocompatibility – the property governing which materials can be implanted.
• Kirschner wire – one of the earlier techniques this implant is positioned against.

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AU 2026202035 was published in the Australian Official Journal of Patents on 2 April 2026 and is open for public inspection. Patent applications represent inventions that are sought to be protected and do not necessarily reflect commercially available products.