Microfracture

Overview

Articular cartilage is a smooth, gliding surface material which covers the ends of your bones at the joints. Think of it like the non-stick Teflon coating in a pan.  Articular cartilage decreases the friction that occurs when your joints move.  When the cartilage becomes injured or worn, the joint gliding can be impaired and become painful.  Injuries or wear to the articular cartilage can manifest as joint pain, clicking, locking, or swelling which can impair function.

Unlike many tissues in the body, the articular cartilage does not have the capacity to heal well.  This is in part because it has a relatively poor blood supply (and thus is not served by the body’s usual reparative inflammatory response) and in part because cartilage wear is most commonly a result of many factors, including the joint alignment, a patient’s activity level, and genetic factors.

What are the different treatment options for injuries to the cartilage?

There are a number of different therapies, techniques, and procedures which can be used to treat injuries or prevent further wear to the articular cartilage.  The treatment that is best for you depends on the type of injury you have, the types of activities you perform, your age, and other associated injuries and medical history.  The medical modalities include:

• Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)
• Physical therapy
• Injections with anti-inflammatory medications or viscosity agents

There are a series of surgical options for more severe cartilage injuries:

• Arthroscopic lavage and debridement
• Microfracture
• Meniscus transplantation (for loss of the meniscal cartilages)
• Osteochondral grafting or Osteoarticular Autograft Transplants (OATs)
• Autologous Chondrocyte Implantation (ACI)
• Osteotomy/Realignment to re-establish a normal joint axis
• Joint Arthroplasty/Replacement

Each of the above surgical modalities has a potential role in the treatment of focal arthritis, and studies have shown that there are optimal indications for each.  In some cases, the procedures should be combined (e.g. an osteotomy to re-align the limb and an OATs procedure to restore a normal cartilage surface).

For many persons, a conservative approach with physical therapy (strengthening and stretching), Non-Steroidal Anti-Inflammatory Medications (NSAIDs), loss of excess weight, and occasionally orthotics may lessen the symptoms of cartilage lesions to a great degree.  When these modalities have been tried in earnest and fail to provide relief, surgical cartilage restorative procedures can be considered.   

The nature of the injury to the cartilage will usually dictate which option is best to treat the problem.  In most cases, X-rays, Magnetic Resonance Imaging Studies (MRI) and occasionally arthroscopy may be required to evaluate the injury to determine the best treatment.  Based on the findings, the experienced surgeon can choose from an armamentarium of procedures to address the injured cartilage tissue and correct any limb alignment problems that may be contributing to the injury.

While some of the procedures (debridement, microfracture, OATs) can be performed arthroscopically (using very small incisions), occasionally minimally-invasive open procedures are performed through small incisions.  Depending on the procedure performed, the rehabilitation period can be extensive, particularly in weight-bearing joints like the knee or ankle.  

Arthroscopy helps a physician evaluate and treat knee arthritis. Using the scope, an experienced surgeon can evaluate the entire knee joint and can identify the injured structures of the knee, including injuries to the ligaments, articular cartilage surfaces, and meniscal cartilages.  Figures 2 and 3 show the normal appearance of the medial (inside), lateral (outside), and patellofemoral (kneecap) joint surfaces of the knee.  Figure 4 and Video 1 shows regions of a knee with severe cartilage damage.  Results are most predictable in the hands of a highly-specialized surgical team that is familiar with various techniques and instrumentation, and who perform such surgery often.  Such a team will maximize the benefits and minimize the risks.  The procedure usually takes a few hours to perform, and the patient may require a hospital stay of 1 to 2 days.

 Downlad Windows Media Player

• Video 1. Arthroscopy of a knee with focal arthritis.  A region of normal, intact cartilage surrounds a region of fragmented, damaged cartilage.  There is a small region of bone exposed beneath the cartilage. (wmv 3.56MB)
  

Patients who undergo a cartilage reconstruction require several months of rehabilitation to protect the repair and optimize regeneration of new cartilage.  Normally a person can return to sedentary work after about 4- to 12-weeks.  Depending on the procedure(s) performed, walking without the need for assistive devices occurs between 6-weeks and 12-weeks.  The return to limited sporting endeavors, usually takes 6 to 9 months, and cutting athletics are usually not advised before 9- to 12-months after the surgery.  Despite the difficulties in treating these lesions, good or excellent results can be expected in about 85% to 90% of persons, and a return to athletic activity is not uncommon.

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