New quality of life by cartilage replacement

The number of cartilage damage increases more and more from accidents, sports injuries and strains. A cartilage cell transplant can reconstruct the damaged tissue and also bring back a new quality of life.

Joint cartilage

Hyaline cartilage - an essential component of our joints

The bone end surfaces of our articular joints are covered with a layer of cartilage which, thanks to its unique composition, allows for practically friction-free movement. This cartilage is known as “hyaline cartilage”.

Hyaline joint cartilage is unique in respect of its biomechanical properties. No material has yet been produced by humans to compare with joint cartilage in terms of stiffness, elasticity and friction.  It is characterized by its high resistance to pressure and shock-absorbing properties. Hyaline joint cartilage consists largely of a matrix – a three-dimensional network of collagen fiber tissue, aggrecan and water. Only 1-3% of its volume is made up of cartilage cells.

Hyaline joint cartilage is unique in respect of its biomechanical properties. No material has yet been produced by humans to compare with joint cartilage in terms of stiffness, elasticity and friction.  It is characterized by its high resistance to pressure and shock-absorbing properties. Hyaline joint cartilage consists largely of a matrix – a three-dimensional network of collagen fiber tissue, aggrecan and water. Only 1-3% of its volume is made up of cartilage cells. Hyaline joint cartilage is unique in respect of its biomechanical properties. No material has yet been produced by humans to compare with joint cartilage in terms of stiffness, elasticity and friction.  It is characterized by its high resistance to pressure and shock-absorbing properties. Thanks to its structure, the matrix guarantees high stability under pressure and good elasticity, both at the same time. Much like a feather, when put under load, the cartilage responds by changing its shape, a shape to which it returns once the load is removed.
As the joint cartilage of an adult has no direct blood or nerve supply, it has only limited self-healing properties if damaged or subjected to change due to illness.
This can lead to major problems: Joint cartilage can’t grow back

Injuries in the knee and ankle joints are increasingly common, caused by accidents, sporting injuries and overloading. For the reasons given above, joint cartilage has only a limited ability to regenerate itself following an injury. In most cases, the defect remains as a gap in the existing cartilaginous coating. Over the years, this becomes larger, until the cartilage of the entire joint is affected by the destruction.

In some cases, the body will attempt to heal the defect, although when it does so only low-grade replacement tissue will generally be produced. With major defects in particular, this scar tissue cannot compensate over time for the load placed on the joint and it is therefore quickly worn off again, with the result that discomfort generally resurfaces in a short space of time.

When this “shock absorber” is damaged, therefore, sooner or later the patient is likely to suffer from health effects such as pain, swelling and difficulty in movement. They can then expect to experience arthrosis and stiffening of the joints over time, possibly leading to a joint replacement operation.

This involves the knee in which the cartilage defect is located being opened up with small chisels. The opening allows blood, bone marrow and stem cells to enter the defect and fill it with scar tissue, creating a replacement or "fibro” cartilage. This replacement cartilage is however fundamentally different from the original joint cartilage both biologically and in terms of tissue structure. For example, it is far less resilient. For this reason, microfracturing should only be used for minor cartilage defects. The principle advantage of the treatment is that it is minimally invasive and only needs to be carried out once.

Autologous osteochondral cylinder transplantation, also known as mosaic plastics, OCT and OATS, is a procedure during which cartilage/bone cylinder is taken from a less stressed part of the joint and inserted into the defect area. This enables a larger part of the defect to be covered with hyaline joint cartilage. However, less resilient fibrocartilage forms in the gaps between the cylinders, resulting in the formation of mixed cartilage tissue. As cartilage bone punches need to be extracted from non-stressed areas, this treatment is also restricted to smaller defects. If too much donor cylinder is taken to cover the defect, cartilage defects at the extraction site can lead to painful arthrosis. Such cases are referred to as “donor site morbidity”.

ACT is the only procedure to enable even larger defect surfaces to be biologically reconstructed, without an increased risk of donor site morbidity. It involves the taking of a small amount of cartilage from a non load-bearing joint area by way of arthroscopy.
The cartilage extracted is taken to our GMP-compliant cleanroom laboratories, where it is prepared. The cells contained in the cartilage (chondrocytes) are isolated from their basic substance and multiplied in cell culture flasks. When the cell count required for the defect area in question is reached, the chondrocytes are seeded in a support material, where they begin to produce cartilage ground substance. The individual implant created is then ready for transplantation after precisely three weeks.
Unlike conventional ACT (in which a flap of bone is stitched over the prepared defect, beneath which the cells are then injected in an aqueous solution), once it has been punched out using special OP instruments in a size and shape matching that of the defect, the cell-populated NOVOCART® 3D carrier material can then simply be inserted into it.  With this form of ACT, there is also no need for time-intensive, watertight stitching, as the carrier is fixed with just a few stitches. The result is a significant reduction in OP time with carrier-coupled ACT. The biomaterial used by TETEC has been developed especially for human cartilage cells and this possesses unique properties when compared to other biomaterials used throughout the world.
Research conducted to date with over 400 patients treated with ACT using our innovative biomaterial shows in particular that a significant reduction has been achieved in complication rates, when compared to the conventional form of ACT – and with, in most cases, equally good clinical results. The procedure itself is much faster and the rehabilitation phase shorter, with the result that in recent years, the matrix-coupled form of ACT using NOVOCART® 3D has become increasingly popular.

With defects in the femoral condyle, patients should rest in bed for 24 hours after the operation. The treated leg should only be subject to a partial load of up to 20 kg for a period of six weeks. The load should then be increased by 20 kg every 14 days. It may also take up to 12 weeks until full weight can be placed on the leg. Once this period is over, sporting activities such as swimming, bicycle riding and walking are permitted, although the patient should not participate in any jumping or running sports for one year following the operation.
With defects of the kneecap/its femoropatellar groove, full weight can immediately be placed on the leg provided the patient has rested for 24 hours following the operation. They must then wear a splint for ten weeks, which limits bending of the knee joint to 50°. The degree of bend is then raised by 20°every 14 days. The patient should not participate in any high-risk or contact sports for one year following the operation.
The follow-up regimes shown are recommendations based on clinical experience gathered in recent years. Naturally, your doctor can also suggest a personal follow-up treatment schedule for you.

Spinal disc

Discs – sensitive active components of the spine

The spine is made up of a total of 24 vertebrae. Thanks to its double s-shape, it is adapted to man's upright posture. Static load of the spine increases from the top to the bottom. Degenerative changes in the lower region are therefore the most frequently occurring. Each vertebra consists of a vertebral body and a vertebral arch. Each vertebral arch has articular processes which are associated with the vertebra above and below via small joints. These joints enable the vertebra to move in certain directions.

The spine is permeated by the spinal channel over its entire length. This channel contains the spinal cord. The vertebral arch’s bony ring offers the spinal cord protection against damage. Cuts in the upper and lower edge of the vertebral arch allow nerves and blood vessels to penetrate.

Hardy fibrocartilage plates – or “discs” - lie between neighboring vertebrae. These act as fixed connectors and elastic buffers between the vertebrae.

Discs are composed of an outer fibrous ring, the annulus fibrosus, and a central elastic core, the nucleus pulposus.

How does a disc prolapse occur?

A disc prolapse is the dislocation of soft core of the disc through a weak point in the fibrous ring, mostly in the direction of the spinal cord or the nerve roots. Most disc prolapses arise in the lumbar portion of the spine in patients aged between 30 and 50 years old. This dislocation leads to narrowing and compression of the nerves and blood vessels. Various symptoms may manifest themselves, depending on the nature and extent of this dislocation. Some prolapses go unnoticed, others will be associated with strong pain, while in some cases paralysis or problems of sensation may arise.

As long as there is pain and feeling is disturbed, in many cases a disc prolapse can be treated without the need for an operation, using medication-based regimes and physiotherapy. Initial rest in bed, as well as relief for and relaxation of the spine, are also important. Should paralysis be present, however, operative therapy, with removal of the prolapse, should be preferred, as nerves can be lastingly damaged through compression.

After a prolapse – whether treated conservatively or operatively – the volume of the disc diminishes. Its supporting and shock absorbing function is then in most cases lastingly destroyed. Increased loss in height of the disc can lead to a relaxation of the spinal structure. This segment loosening is usually followed by instability, which may lead to renewed compression of the nerves and of the spinal column.

A cycle of pain begins, which is associated with episodes of inflammation, the dying of disc cells, ossifications and often also with a pathological blood vessel and neuronal invasion of the affected disc.

With a slipped disc, there is often subsequent progressive degeneration of the disc structures, which can lead to lasting discomfort and serious complications. The transplantation of a patient’s own disc cells (ADCT = Autologous Disc Cell Transplantation) is currently the only method known to prevent further degeneration.

The prolapsed disc tissue is removed in a minimally invasive operation. The cells are then cultivated and multiplied in our cleanroom laboratories. Three months after the operation, the cells can be injected in a polymerizable hydrogel through the skin into the remaining disc. The relatively long period between extraction of the tissue and cell transplantation must be adhered to in order to enable the protective fiber ring, damaged by the prolapse, to heal. Combined with the use of polymerizable biomaterial, this ensures that the cells in the damaged disc structure can set and will not leak through an unsealed point. The patient can leave the hospital again 1-2 days after injection of the cells.

The intervention is then followed by standardized physiotherapeutic care, on which no major physical restrictions are placed.


Cartilage damage in the knee and ankle joint and slipped discs considerably increase the risk of the degeneration of the affected tissue.
Early treatment is required if these degenerative processes are to be avoided, treatments capable of reconstructing the damaged tissue.
Depending on the size of the cartilage defect, a range of treatment options are available in knee and ankle joint interventions (microfracturing, mosaic plastics, ACT). A new method is now available for the treatment of slipped discs, one that can prevent loss in height of the intervertebral disc and with it increasing segment loosening:
ADCT (“Autologous Disc Cell Transplantation”)

ACT and ADCT are cell-based procedures used in regenerative medicine, characterized essentially by three steps: 

3 steps

1. Extraction of a small piece of tissue (biopsy)

2. Laboratory cultivation of the cells extracted

3. Transplantation of the cells to the defect area

To ensure that the cultivated cells are capable of regenerating the corresponding tissue, it is extremely important to check their quality (cell phenotype) immediately prior to transplantation. For this reason, for every implant we perform validated cellular and molecular biological quality controls using state-of-the-art analytical methods, informing the treating physician in writing about the quality of the cells to be transplanted. Our development team has been honored with a prestigious science award for outlining the scientific principles of a newly developed method for significantly increasing the quality of transplanted cartilage cells. This is our way of ensuring that you receive only vital and functioning cell implants from us and your doctor.