Autologous Chondrocyte Implantation (ACI)

This guide explains Autologous Chondrocyte Implantation (ACI) in clear, patient-friendly terms and follows the key sections patients usually ask about before treatment.

Autologous Chondrocyte Implantation (ACI) is a procedure used to address focal cartilage defects. It aims to relieve pain, improve stability or motion, and help you return to daily activities. Your surgeon will tailor the plan to your anatomy, symptoms, and goals.

This procedure treats focal cartilage defects. It may be considered when symptoms persist despite activity modification, therapy, or other non-surgical care.

People with ongoing pain, instability, or functional limits that do not improve with conservative care may be candidates. A specialist confirms the diagnosis with exam and imaging and discusses whether this procedure is the best option.

• Persistent knee pain that limits daily tasks
• Swelling or recurrent effusions
• Catching, locking, or mechanical symptoms
• Instability or the knee giving way
• Reduced range of motion or stiffness

• Reduce pain and inflammation
• Improve stability, alignment, or motion
• Restore function for work, exercise, and daily life
• Protect joint structures when possible

Autologous Chondrocyte Implantation (ACI) addresses cartilage damage by smoothing, stimulating repair, or restoring cartilage surface. The technique depends on defect size, location, and the condition of surrounding bone and cartilage.

• Debridement, marrow-stimulation, or graft-based restoration options.
• Single-stage vs. staged approaches depending on the technique.
• Defect-specific strategies based on size, depth, and location.

Your team will review your medical history, perform a focused knee exam, and discuss symptoms and goals. This helps confirm the diagnosis and plan the safest, most effective approach.

• X-rays to assess alignment and joint space
• MRI to evaluate soft tissues like cartilage, meniscus, and ligaments
• CT or ultrasound when detailed bone or soft-tissue evaluation is needed
• Lab tests if infection or systemic issues are suspected

• Follow pre-op instructions on eating, drinking, and medication use
• Arrange transportation and at-home support
• Set up a recovery space with ice, pillows, and assistive devices
• Discuss any medical conditions or allergies with your care team

Your surgeon will advise which medications to pause, continue, or adjust. This often includes blood thinners, anti-inflammatories, and certain supplements. Do not stop prescribed medications without medical guidance.

Depending on the procedure, anesthesia may be general, spinal, regional nerve block, or a combination. Your anesthesiologist will recommend the safest option for your health and comfort.

1. Anesthesia and access to the joint (often arthroscopic).
2. Assessment of the cartilage defect.
3. Preparation of the defect bed.
4. Application of the selected repair or restoration technique.
5. Closure and dressing.

Many procedures are outpatient or short-stay. More complex reconstructions, fractures, or infections may require a longer hospital stay for monitoring and therapy.

Pain control is typically multi-modal and may include ice, elevation, prescribed medications, and activity modification. Your team will provide a plan that balances comfort with safe healing.

• Infection or wound problems
• Bleeding or blood clots
• Stiffness or loss of motion
• Persistent pain or incomplete symptom relief
• Injury to nearby nerves or blood vessels

Outcomes vary based on the condition treated, surgical technique, and rehabilitation. Many patients experience meaningful pain relief and functional improvement, especially when they follow the rehab plan.

Rehabilitation restores motion, strength, and confidence. The program is tailored to the procedure and may progress from gentle mobility to strength and balance training.

Weight-bearing and walking aids depend on the procedure and tissue healing. Follow your surgeon's instructions to protect repairs and avoid setbacks.

Activity restrictions are phased. High-impact activity and sport are typically reintroduced only after strength, stability, and healing milestones are met.

Keep incisions clean and dry as instructed. Follow-up visits allow your surgeon to monitor healing, remove stitches if needed, and adjust the rehab plan.

• Fever, chills, or increasing redness around the incision
• Sudden increase in pain, swelling, or drainage
• Calf pain or shortness of breath
• Loss of sensation or new weakness

Alternatives may include activity modification, physical therapy, bracing, medications, injections, or other surgical options. Your surgeon will review which alternatives fit your diagnosis and goals.

Costs vary based on setting, complexity, implants, and insurance coverage. Ask your provider about pre-authorization, out-of-pocket costs, and coverage details.

• Is this the best procedure for my diagnosis and goals?
• What outcomes should I reasonably expect?
• What are the key risks in my case?
• What does my rehab plan look like?
• When can I return to work, driving, and sports?

• Autologous Chondrocyte Implantation (ACI) addresses focal cartilage defects.
• Technique choices depend on anatomy, tissue quality, and goals.
• Rehabilitation is essential for long-term success.
• Discuss expectations and alternatives with your surgeon.