Surgeons can use this 3D-printing pen to “draw” people new hip joints

Australian medical researchers have designed a pen which can “draw” on damaged bone with an “ink” made from human cells, to treat diseases like arthritis.

The BioPen was invented by the ARC Centre of Excellence for Electromaterials Science (ACES) in collaboration with orthopaedic surgeons at St Vincent’s Hospital in Melbourne.

Create bespoke body tissue

It will mean surgeons can inject customised human stem cells, carried by a protective bio-ink, on to damaged cartilage and joints.

A light source is attached to the pen, which is used to project UV light to solidify the cells once they’ve been “drawn” on.

Once implanted in the human body, the cells will multiply and turn into specific nerve, muscle or bone cells, eventually forming working tissue.

This technique will be a new alternative operation for those with sporting injuries or diseases that result in joint erosion such as arthritis, and need operations such as hip and knee replacements.

Designing joints by hand

It will allow orthopaedic surgeons, who deal with issues such as joint replacements, and tendon, muscle and bone reconstruction, to design implants that are specific to each person, says ACES.

It also means they will be able to do this during surgery, drawing “freeform patterns” by hand, rather than relying on “pre-prepared” implants created by 3D bioprinters, which can be “difficult”.

Faster recovery of tissue

Designing joints based on somebody’s own stem cells also “encourages the body to heal itself”, says ACES, which means the regeneration of bone and cartilage will be faster.

The research company adds the 3D printing pen has been designed with “constraints of surgery in mind”, by making it “small, lightweight, ergonomic and sterilisable”. It is made from 3D-printed medical-grade plastic and titanium.

First conceived as a prototype in 2013, the BioPen has undergone testing and was proven this month to be successful, with a live cell survival rate of 97%.

It is not yet clear if or when it will be rolling out for use in hospitals.