Cartilage Surgery: Information & Cartilage Specialists

Cartilage surgery involves joint-preserving procedures for cartilage regeneration and reconstruction.

Cartilage surgery is a specialized field of treatment within the medical disciplines of orthopedics and trauma surgery. 

Depending on the affected joint, cartilage surgery is divided into the following subspecialties:

• Shoulder Joint Surgery
• Hip Surgery
• Knee surgery
• Foot and Ankle Surgery

The bones in our joints are covered with a protective layer of cartilage that has unparalleled sliding properties. It ensures that as little friction as possible occurs when the joint moves.

Articular cartilage consists of a dense network of cartilage cells and collagen fibers. It is about 80% water. This gives the cartilage elasticity and allows it to function as a shock absorber that cushions every movement.

Loading and unloading the joint are essential for supplying the cartilage with nutrients. The movement of the joint pumps nutrients into the cartilage. That is why physical activity is very important for the care and maintenance of the joints.

Cartilage has no blood vessels—and consequently, its ability to regenerate is limited. Once cartilage damage occurs, it is therefore permanent, especially in adulthood. Over time, this damage typically leads to larger cartilage defects.

The most common causes of cartilage disorders are directly related to the musculoskeletal system:

Wear and tear are considered the main causes of cartilage damage. As we age, cartilage loses its elasticity. The water content of the cartilage also decreases. The once-smooth cartilage surface becomes rough and brittle.

Now, the layers of cartilage rub against each other with every movement of the joint. This causes tiny particles to break off—the surface of the cartilage wears down and fine cracks form.

Ultimately, this can lead to the complete destruction of the cartilage surface. Doctors refer to this mostly age-related cartilage degeneration under the umbrella term osteoarthritis.

In addition to age-related joint wear and tear, accidents and sports injuries can also lead to cartilage damage. Those affected must therefore seek treatment as soon as possible to prevent permanent damage.

Joint misalignments (e.g., bowlegs and knock-knees) are also associated with excessive stress on specific joint areas and cartilage surfaces. The wear and tear on the cartilage surface is correspondingly severe in these stressed areas.

Other causes of cartilage damage include:

• Metabolic disorders
• Overweight (obesity)
• Circulatory disorders

Whether and when cartilage surgery is an option depends largely on the extent of the cartilage damage.

Doctors classify cartilage damage into four grades:

1. Grade 1: The surface of the cartilage is still intact but has already softened.
2. Grade 2: There are tears in the cartilage that extend to a depth of less than 50% of the cartilage’s thickness.
3. Grade 3: There are deep tears or fractures in the cartilage that extend to more than 50% of the cartilage’s thickness. In some cases, they may extend all the way to the bone surface.
4. Grade 4: There is a complete cartilage defect that exposes a large area of the underlying bone.

For Grade 1 and 2 cartilage damage, cartilage surgery is not necessary. 

In these cases, conservative treatments are used to stabilize the cartilage damage, such as:

• hyaluronic acid injections,
• muscle-building exercises, or
• weight loss

The situation is different for grades 3–4. These cases involve deep cartilage damage that can usually be treated with cartilage surgery.

An important prerequisite: The remaining cartilage and joint function must still be well preserved.

Since conventional X-rays only provide evidence of cartilage damage once it is highly advanced, magnetic resonance imaging (MRI) is the method of choice. An MRI makes even small cartilage defects visible and provides information about cartilage damage as early as the initial stage.

An accurate diagnosis is also possible with arthroscopy—that is, a joint endoscopy.

Various procedures are available in cartilage surgery. Which one is used depends on individual factors, such as:

• The extent and location of the cartilage damage
• Symptoms
• The cause of the defect
• Cartilage Regeneration via Microfracturing

Microfracture is one of the procedures that stimulate bone marrow. This arthroscopic surgical method is used for minor cartilage damage.

It can be performed during an arthroscopy. If the doctor detects cartilage damage during the procedure, he immediately removes the damaged cartilage tissue and makes multiple perforations in the underlying bone.

The fluid that oozes out contains bone marrow stem cells, which stimulate the growth of replacement cartilage tissue. The goal is to close the lesion again.

OATS (Osteoarticular Transfer System) Cartilage Transfer

In this procedure, the doctor removes a cylindrical section of bone and the associated cartilage from the healthy part of the joint. He then implants the excised piece into the damaged cartilage area.

This allows new cartilage tissue to form over the defect. This cartilage surgery is suitable for smaller but deeper cartilage defects.

The German Society for Orthopedics and Trauma Surgery (DGOU) emphasizes the growing importance of:

• cartilage cell transplants and 
• bone marrow-stimulating procedures

For this reason, the DGOU established a so-called cartilage registry. It anonymously documents the recovery process following these procedures and thus provides important information for medical research.

If a misalignment of the leg axis is responsible for the cartilage damage, treatment limited to cartilage surgery alone is not sufficient. 

In such cases, an additional realignment osteotomy is required prior to the actual cartilage surgery to correct the joint misalignment.

A cartilage surgery procedure typically requires a 2–3-day inpatient hospital stay. After discharge, patients undergo a postoperative recovery phase, the specifics of which vary depending on the procedure.

In any case, this is followed by a postoperative recovery period of about 6 weeks, during which the patient uses forearm crutches.

To restore mobility to the treated joint, intensive physical therapy is also required.

For knee cartilage surgery, the patient is provided with a motorized splint for use at home. This helps them get back to their daily routine quickly.

As a rule, the joint can bear a full load again after about 3 months. Nevertheless, it is advisable to avoid sports that place heavy strain on the joints during the first year.

Reconstructive procedures that restore destroyed or damaged cartilage are extremely complex. Cartilage surgery therefore places high demands on the surgeon and requires specialized expertise as well as extensive experience.

With a specialist in cartilage surgery, you are in the best hands for your needs.