Microfracture

Understanding Cartilage Damage and Why Microfracture May Be Considered

Articular cartilage provides a smooth, low-friction surface that allows the knee to bend and straighten comfortably. A knee cartilage injury or gradual wear can lead to small defects that expose the underlying bone. These areas may cause discomfort during walking, squatting, or twisting, especially when a load is placed directly over the defect.

Common Reasons Cartilage Defects Occur

• A twisting injury during sport
• Direct impact on the knee
• Gradual thinning related to local overload
• Damage associated with ligament injuries or meniscal injuries

Microfracture may be discussed if the damaged area is contained, is not too large, and has well-defined edges that respond to stimulation.

How Cartilage Responds to Injury

New cartilage does not reform naturally once a defect extends through the full thickness of the surface. This is why some symptoms continue even after swelling settles. Among cartilage regeneration techniques, microfracture aims to use the bone’s ability to release healing cells to help create a protective layer where smooth cartilage is missing.

How Microfracture Surgery Works

Microfracture is an arthroscopic cartilage treatment performed through small incisions. The goal is to encourage a healing response by creating tiny channels in the bone beneath the cartilage defect.

Key Steps in the Procedure

• Damaged or loose cartilage is carefully stabilised or removed
• The underlying bone surface is prepared to create a clean edge
• Small openings are made in the exposed bone to allow marrow elements to enter the defect
• These cells form a protective clot that can mature into repair tissue over time

The microfracture procedure does not recreate normal hyaline cartilage. Instead, the body forms a type of fibrocartilage that may improve cushioning and reduce symptoms depending on the size and location of the defect.

What the Surgeon Assesses During Arthroscopy

Microfracture is often part of a broader arthroscopic assessment. At the time of surgery, the surgeon evaluates how the defect behaves under load, whether there are small loose fragments contributing to irritation, and whether associated structures need attention to support a stable healing environment.

When Microfracture May Be Appropriate

Microfracture is typically considered for contained cartilage defects in specific situations.

Features That May Support Use of Microfracture

• A smaller, well-defined defect
• Symptoms that correlate with the location of damage
• Good surrounding cartilage quality
• Adequate limb alignment
• No advanced arthritis

When Other Approaches May Be Discussed

Microfracture may be less suitable when:

• The defect is large or involves multiple areas
• There is advanced degenerative change
• Alignment or instability concerns need to be addressed first
• Previous procedures have affected the surrounding structures

Factors That Influence Whether Microfracture Is Appropriate

Your surgeon will also consider joint mechanics during daily tasks, how your symptoms behave with activity, and whether strengthening or non-surgical management has already been trialled. Microfracture tends to work best when the defect is the primary cause of discomfort rather than part of a wider pattern of wear.

Recovery After Microfracture Surgery

Microfracture recovery aims to protect the developing repair tissue while gradually restoring movement and strength. Healing time can vary depending on the defect size, location, and your overall knee health.

General Components of Rehabilitation

• Protected weight-bearing for several weeks
• Early range-of-motion exercises to maintain joint mobility
• Progressive strengthening guided by structured physiotherapy
• Gradual return to functional tasks and low-impact activity

High-impact loading or deep squatting is usually delayed until the repaired tissue matures. Results may vary depending on individual circumstances. Specific timelines are determined during postoperative review.

Why Early Rehabilitation Needs to Be Gradual

The developing tissue is initially soft before gradually strengthening. Physiotherapy focuses on maintaining mobility while preventing excess load on the repair site, followed by progressive strengthening that supports long-term joint control.

Potential Benefits and Considerations

Microfracture may help reduce symptoms in selected cases, particularly when the defect is small and mechanical factors are well controlled.

Possible Advantages

• Minimally invasive technique
• Can stimulate tissue growth in areas where cartilage is absent
• Often performed as part of arthroscopic treatment for related issues

Considerations to Discuss With Your Surgeon

• The new tissue differs from native cartilage
• Outcomes depend on defect size, location, and knee mechanics
• Some activities may need to be modified during recovery
• Progress is monitored over several months

Understanding How Repair Tissue Behaves Over Time

Although microfracture may improve comfort, repaired tissue does not behave the same as natural cartilage. Regular follow-up helps track how it matures and how the knee responds to increasing activity.

How Microfracture Fits Within Broader Knee Care

Microfracture is one of several cartilage treatment options. Depending on your condition, non-surgical management, biological treatments, realignment procedures, or other cartilage repair techniques may also be discussed.

Microfracture may be most appropriate when:

• A specific lesion is identified
• Symptoms persist despite conservative care
• The joint environment is favourable for repair

Dr Jonathan Negus will consider the whole-joint picture, including alignment, ligament stability, and meniscal support, before recommending a treatment pathway.

Why Microfracture Is Only One Part of Joint Care

Knee cartilage repair works best when underlying contributors, such as strength deficits or biomechanical factors, are also addressed. Supporting the joint from multiple angles helps protect the repair site and overall knee function.

When to Seek Review for Cartilage Symptoms

You may consider assessment if you experience:

• Pain that occurs with load-bearing or twisting
• Swelling that recurs after activity
• Localised tenderness over a known area of damage
• Difficulty with stairs, deeper bending, or certain sports
• Uncertainty about MRI findings or suitability for cartilage procedures

A knee surgeon in Sydney can help determine whether microfracture or another approach may be suitable based on your imaging, examination, and individual condition.

Next Steps

A clearer understanding of how microfracture works can help you feel more confident when discussing treatment options. Taking the time to review your imaging, symptoms, and activity demands with a specialist ensures your care plan is matched to your goals.

If you would like to understand more about cartilage repair options or discuss whether microfracture may be appropriate, you can arrange a consultation with Dr Jonathan Negus for a personalised assessment of your symptoms and treatment goals.

This information is intended as a general guide. It does not replace individual medical advice. Assessment and treatment recommendations vary depending on personal circumstances. Please speak with a qualified health professional for guidance specific to your situation.