New Technique Combines Fat Tissue With Collagen for Cartilage Repair

Single-Surgery Option for Full-Thickness Knee Cartilage Damage

Cartilage injuries in the knee have long been difficult to treat. In 1743, a surgeon famously declared them nearly untreatable. Today, new approaches offer hope for patients with these painful conditions. A team of surgeons from Brazil and Singapore has developed a technique called LIPO-AMIC. This procedure combines two proven methods into one surgery. It uses a collagen membrane along with processed fat tissue from your own body.

The goal is to repair full-thickness cartilage lesions. These are injuries where the cartilage is damaged all the way through. The technique aims to improve healing quality while keeping the procedure minimally invasive.

How the Procedure Uses Your Body's Own Healing Cells

The LIPO-AMIC technique relies on adipose-derived stem cells (stem cells from fat tissue). These cells have a remarkable ability to develop into cartilage cells. They also release helpful signals that reduce inflammation and support tissue repair.

During the procedure, surgeons collect about 60 milliliters of fat from your abdomen or thigh area. They use a small cannula through a tiny incision. The fat is then processed using the Lipogems system. This involves three cycles of gentle mechanical processing. The result is micro-fragmented adipose tissue (specially processed fat tissue). This creates about seven to ten milliliters of a thick, gel-like material rich in regenerative cells.

Collagen Membrane Creates Protective Cover Over Injury

The technique also uses a collagen membrane made from types I and III collagen. This membrane serves multiple important purposes:

• Creates a protective barrier over the damaged area

• Holds the fat tissue graft securely in place against the cartilage defect

• Provides a scaffold that helps new tissue form properly

• Stabilizes the healing environment during recovery

Surgeons carefully cut the membrane to match the exact shape of your cartilage injury. They apply the processed fat tissue to one side of the membrane. Then they suture it in place over the prepared lesion site.

Surgeons Can Address Multiple Problems in One Operation

One significant advantage of this technique is efficiency. Surgeons can treat several knee problems during the same surgery. While the fat tissue is being processed, the surgical team can perform other necessary procedures. These might include:

• Repairing torn ligaments or meniscus

• Correcting leg alignment issues (if your leg bows inward or outward)

• Treating other cartilage damage in different areas

Proper leg alignment is crucial for long-term success. If your leg has significant malalignment, the surgeons may perform an osteotomy. This procedure adjusts the bone angle to reduce stress on the repaired cartilage.

Careful Preparation of the Injury Site Supports Better Healing

The surgeons access the cartilage through a small incision near the kneecap. They prepare the damaged area with great precision. First, they create clean, perpendicular edges around the lesion. These edges help contain the graft and anchor the membrane.

Next, they gently remove the damaged calcified cartilage layer. They must avoid going too deep and damaging the bone underneath. Small points of bleeding indicate they have reached the proper depth. This bleeding brings bone marrow cells to the area. These cells work together with the fat-derived stem cells to promote healing.

What This Means for Patients Considering Treatment

The LIPO-AMIC technique represents an evolution in cartilage repair. It builds on the established AMIC procedure by adding biological enhancement from your own fat tissue. Previous research has shown that adding fat-derived cells to cartilage repair procedures produces better results than surgery alone.

This approach offers several potential benefits. It uses your own tissue, eliminating donor compatibility concerns. The procedure can be completed in a single surgery. It combines mechanical support from the collagen membrane with biological healing power from stem cells.

However, this paper describes the surgical technique rather than reporting patient outcomes. Patients should discuss with their surgeon whether this approach is appropriate for their specific situation. Factors like lesion size, location, and overall joint health all influence treatment decisions.

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Source: Debieux et al., Arthroscopy Techniques, 2024.