Knee arthritis is the progressive deterioration and disorganization of the joint with the main cause being the degenerative process over time, degenerative osteoarthritis, injury, post-traumatic or an underlying condition, rheumatoid arthritis.

Degenerative knee arthritis that occurs in older people and post-traumatic in younger people cause swelling, joint pain, difficulty moving or performing daily activities. When osteoarthritis is at an advanced stage, 4 according to Kellgren-Lawrence with severe clinical and radiological findings, joint replacement (total arthroplasty) is the surgical treatment method of choice.

But what happens when we talk about stage 3 early 4 arthritis with severe pain, with a meniscus or articular cartilage tear that prevents the still biologically active sufferer from engaging in the activities he enjoys?

Arthroscopic debridement of the joint and especially arthroscopic meniscectomy for a meniscal tear in an arthritic knee require great care. For a meniscectomy in an arthritic knee to be successful, the following conditions must be met:

• Meniscal pain must be predominant of the arthritic
• The mechanical axis of the affected lower extremity must present at most up to 7th degree of laxity or vulsion
• There should be no deformity of gait and marked unsteadiness.
• There should be no obliteration (less than 2 mm) of the painful mediastinal space on an anteroposterior radiograph of the knee in standing position and 30° of flexion.

It should be emphasized that 73% of patients with poor mechanical axis and severe osteoarthritis show no improvement or even worsening of their symptoms after arthroscopic meniscectomy and 48.8% of them will need total knee arthroplasty in the postoperative period.

So what solution can we offer middle-aged, active, athletic patients with painful, limiting osteoarthritis of the knee?

The answer is biologic knee replacement. We talked about this for the first time in 2016 and now we have both necessary data and new sophisticated techniques.

Includes:
• Ligamentous stabilization of the knee with individualized reconstruction of the torn anterior cruciate ligament (ACL). There is now, based on indications, the possibility of replacing or repairing the ACL or repeat surgery with a quadriceps autograft. Stabilization of lateral knee ligaments by stem cell infusion.
• Meniscal transplant: In knees with an earlier meniscectomy in which there is still a remnant meniscus with good vascularity, a synthetic porous meniscal polymer is placed which is sutured to the remnant of the old meniscus after cleaning it. If the meniscus is completely missing, a whole cadaveric meniscus is transplanted. In both cases the technique is arthroscopic with very good results.
• Cartilage transplantation if there is a cartilage deficit greater than 2 sq.cm. The operation of taking chondrocytes from a non-load-bearing surface of the affected knee and re-implanting them in the deficient lesion is done in one stage, Autocart technique. In smaller damage, the injection of stem cells alone or in combination with the placement of a self-adhering membrane made of hyaluronic acid, a basic component of cartilage, has excellent results. In patients too young for arthroplasty and old enough for biologic therapies or failing cartilage repair techniques, we will soon have the option of applying mini-metal and focused surface techniques.

The above can be achieved by using autologous growth factors, such as PRP or adult mesenchymal cells from bone marrow or adipose tissue.
Necessary conditions for the success of biological knee replacement are arthritis up to the beginning of the 4th stage with a good anatomical axis, otherwise corrective osteotomies are also required.

Biological knee replacement does not exclude the possibility that eventually this knee will be led to total arthroplasty with the use of metallic materials. But it is important to offer biologically active patients with arthritis some quality years of life with sports or other physical activities before they are led to total knee arthroplasty.

Biologic treatments offer pain reduction and improved joint mobility-function by 83% in the first year, and must be performed in organized, scientifically documented, Orthopedic Regenerative Medicine Centers.