Introduction

Knee care · Cartilage injuries

Cartilage repair surgery: damage, options and recovery

Articular cartilage has limited capacity to heal itself. Repair options do exist, but the right one depends on the defect, the joint and the person. No outcome is promised.

Arrange a cartilage or knee assessment

Compare cartilage repair techniques

Dr Sean LeoOrthopaedic Surgeon, Singapore

Clinic enquiries · Not an emergency service

Illustrative image

Cartilage repair in brief

Cartilage has limited capacity to heal itself, and it does not heal well on its own. Untreated significant defects can, over time, contribute to progressive joint degeneration and osteoarthritis, but no individual outcome is guaranteed. Conservative care is the first line of treatment and does not regrow cartilage. Surgery is reserved for specific defects, usually focal and symptomatic ones. No technique regrows true hyaline cartilage, is proven to prevent arthritis, or is universally best. Assessment relies on your history, a physical examination and imaging. Recovery takes months and varies from person to person.

What’s covered on this webpage

Follow the route in order, or jump to the stop you need. Stops you have read are marked.

What is articular cartilage, and how does it get damaged

What is articular cartilage, and how does it get damaged?

Hyaline cartilage: the smooth bearing surface

Articular cartilage is the smooth, low-friction bearing surface at the ends of bones in the knee. It has no direct blood supply, no nerves and no lymphatic vessels. It also contains only a sparse population of low-activity cells. For these reasons it has limited capacity for self-repair and does not heal well on its own.

Traumatic damage vs wear-and-tear degeneration

Damage to this cartilage tends to fall into three broad groups.

First, an acute injury can produce a focal chondral or osteochondral defect. This often happens alongside ligament or meniscal injury, a dislocation or a direct impact.

Second, there is osteochondritis dissecans (OCD), a focal lesion of the bone just under the cartilage. It occurs most often in adolescents and young adults, most commonly in the knee, at the end of the thighbone (femur). Its cause is not fully understood.

Third, there is degenerative wear and tear as part of osteoarthritis. Osteoarthritis is a whole-joint condition, not a cartilage-only one, and a focal traumatic defect is not the same condition as widespread osteoarthritis.

Articular cartilage is not the meniscus

The meniscus is a different structure from articular cartilage. If you are looking for information about meniscal injury, it has its own page: meniscus repair surgery.

Why cartilage heals poorly

Because cartilage has no direct blood supply, it has little capacity to repair itself. When a healing response does occur, for example when a defect penetrates the underlying bone, the tissue produced is fibrocartilage, which is mechanically inferior to native hyaline cartilage.

About osteoarthritis risk

Untreated significant defects can, over time, contribute to progressive joint degeneration and osteoarthritis. Progression is not guaranteed, and no individual risk percentage exists.

Can damaged cartilage repair itself

Can damaged cartilage repair itself?

No, not on its own, and no current treatment truly regrows perfect cartilage. Cartilage has no direct blood supply, so it has little capacity to repair itself. Surgery can produce repair tissue and relieve symptoms, but it cannot restore true hyaline cartilage or guarantee protection from arthritis.

Arrange a cartilage or knee assessment

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Symptoms of cartilage damage

When cartilage is damaged, the joint surface may no longer be smooth. Moving bones along a damaged joint surface causes pain.

Some people also notice mechanical symptoms, such as catching or locking.

In osteochondritis dissecans (OCD), pain and swelling of the joint are the most common first symptoms. They are often brought on by sports or physical activity. Advanced cases may cause joint catching or locking.

Cartilage damage often occurs alongside other knee injuries, such as a meniscus or ligament tear. It can be hard to diagnose, because cartilage does not show on an X-ray.

Video: Cartilage Wear: Why Early Changes Matter More Than You Think — 1:14About this video

When should a cartilage problem be assessed

When should a cartilage problem be assessed?

Knee pain that keeps returning, or a knee injury, is worth having assessed.

A damaged joint surface causes pain. Cartilage defects left untreated can lead to progressive joint degeneration, chronic pain and functional impairment. This does not happen to everyone, and no individual outcome can be predicted.

Assessment matters for another reason. A normal X-ray does not rule out cartilage damage, so a problem can be missed without a proper examination.

What does assessment involve?

Understanding a knee cartilage problem starts with listening to you, then building a picture with examination and imaging. No single test tells the whole story, and imaging on its own does not decide treatment.

History and examination

Your doctor will begin with your history: how the injury happened, the symptoms you have, and how active you are. This is combined with a physical examination of the knee. Together these help narrow down what might be going on before any scan is arranged.

Imaging: what X-ray can and cannot show

An X-ray shows bone and whether the space between the bones of the joint has narrowed. What it cannot show is the hyaline cartilage itself. Cartilage contains no calcium, so it does not appear on an X-ray. Because of this, a normal X-ray does not rule out cartilage damage. X-rays are still useful: they help rule out other problems and let your doctor assess alignment and any arthritis present.

MRI (magnetic resonance imaging) and, when needed, arthroscopy

MRI is the key non-invasive imaging test for cartilage. It is good at confirming that cartilage is normal, but less good at detecting every lesion. A 2024 systematic review and meta-analysis by Chen et al. (43 studies, 3,706 patients) reported MRI overall performance, measured as area under the curve, of 0.91. Pooled sensitivity varied with technique: about 0.63 for 2D MRI, 0.79 for 3D MRI and 0.82 for quantitative MRI. Sensitivity was higher at 3 tesla (0.79) than at 1.5 tesla (0.67). These figures are tied to the technique and field strength used, so they vary.

In plain terms, this means MRI reliably reassures when cartilage looks normal, but it can miss some mild or superficial lesions. Those are sometimes only found at arthroscopy, where the surgeon looks at the joint directly through a small camera. Arthroscopy remains the most definitive examination when direct inspection is needed.

Why MRI does not see everything

MRI is excellent at confirming healthy cartilage, which is why a clear scan is reassuring. Its sensitivity for finding every small lesion is more modest, and mild or superficial damage can be overlooked. This is not a fault of the scan itself but a reflection of what cartilage injuries look like on imaging. When a lesion is strongly suspected but not clearly seen, arthroscopy offers the most definitive look by allowing the surgeon to inspect the joint surface directly.

Non-surgical treatment options

Non-operative care is the usual first step for a cartilage problem in the knee. It is a valid long-term approach, not a stopgap. Its goal is to relieve symptoms and improve how the knee functions. What it does not do is regrow the smooth cartilage that has been lost.

Non-surgical care usually includes several parts. These are changing how you load the knee, managing your weight, physiotherapy and exercise, and pain relief through medications or injections. Among these, weight loss and exercise carry the strongest evidence for easing symptoms and reducing the load passing through the joint. Many patients improve without an operation, and a substantial proportion can be managed this way over the long term, particularly when the change is diffuse or arthritic, or when symptoms are mild.

One honest caveat. Most of the evidence for non-surgical care comes from research on osteoarthritis, which is then applied to focal cartilage defects. Dedicated trials of conservative care for focal defects are scarce. This does not mean the approach is unhelpful. It means we should track your progress carefully rather than assume a given result.

Activity modification, weight management and physiotherapy

Changing how you load the knee can reduce pain during everyday activities. Physiotherapy aims to strengthen the muscles around the joint and improve how it moves. Weight management, where it applies, reduces the load passing through the knee with every step. These measures are useful whether or not you later have surgery, and they remain the foundation of care.

Injections and medication

Medications and injections may be discussed during your assessment as options for symptom relief. Your doctor can talk through which options, if any, are appropriate in your situation.

Video: Cartilage Damage: Treatment Options at a Glance — 0:54About this video

When is cartilage repair surgery considered

When is cartilage repair surgery considered?

Surgery is considered for a focal, symptomatic defect that has not settled with non-surgical care. Not every defect needs an operation. Many are managed without one.

The decision is individual, and several factors shape it. These include the size, location and depth of the defect; the alignment of the joint; your symptom burden; your activity goals; any prior treatment; and your age and the general condition of the joint. No single factor is decisive, and there is no automatic candidacy.

For microfracture, the evidence supports its best use in small, contained, full-thickness defects in younger patients whose joints are otherwise healthy. The procedure may be less suitable outside those circumstances.

For autologous chondrocyte implantation (ACI), UK guidance from the National Institute for Health and Care Excellence (NICE) recommends it only when specific conditions are met. These are that you have not had previous cartilage-repair surgery, that there is minimal osteoarthritic damage, that the defect is larger than 2 cm², and that the procedure is done at a tertiary referral centre.

Surgery carries no guaranteed benefit, and candidacy is assessed case by case. If you and your doctor decide on an operation, you will know beforehand which procedure is being considered and why it suits your particular knee.

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Structure / Patient / Goal

Deciding together

Structure / Patient / Goal

The decision is organised around three questions: the structure, the patient and the goal. They are worth separating, because a scan can only ever answer the first one.

Structure: what the defect actually is

This covers the size, location and depth of the defect, whether it is contained, and the alignment and general condition of the surrounding joint — the defect characteristics described earlier on this page. Structure is what the assessment, the X-ray and the MRI add.

Patient: who you are and what you can carry

Your age, your general health, your symptom burden, your activity level, and your tolerance for the recovery time and the risk that a repair may not hold up all shape which option is reasonable, as do practical constraints such as work and caregiving. These are not things a scan can answer.

Goal: what you want to get back to

Whether the aim is everyday walking without worry, recreational sport or a return to competition changes what a useful outcome looks like, and how each procedure’s recovery timeline weighs against it.

Your plan

Together, Structure / Patient / Goal provides a practical way to weigh the candidacy factors above without treating any single factor — or any one scan — as decisive on its own.

Cartilage repair techniques

Cartilage has a limited ability to heal on its own. Repair techniques aim to fill a cartilage defect with tissue and reduce symptoms, but no technique replaces the defect with the same healthy hyaline cartilage that was there before. The choice depends on the size and location of the defect, the state of the surrounding joint, and the individual patient.

Microfracture / marrow stimulation

Microfracture is a single-stage arthroscopic procedure. The surgeon makes tiny fractures in the bone beneath the defect so that bone marrow cells can reach the surface and form repair tissue.

Its main limitation is the quality of that tissue. The tissue formed is fibrocartilage rather than hyaline cartilage, and it is mechanically inferior to the original surface.

AMIC — autologous matrix-induced chondrogenesis (enhanced microfracture)

AMIC (autologous matrix-induced chondrogenesis) is an enhanced, single-stage form of bone-marrow stimulation. Like microfracture, it starts with tiny perforations in the bone beneath the defect so that marrow cells can reach the surface. AMIC then adds a collagen membrane, fixed over the defect with fibrin glue or sutures, which covers and stabilises the resulting blood clot so the cells forming within it are held in place while repair tissue develops.

Autologous chondrocyte implantation (ACI) and matrix-induced ACI (MACI)

ACI (autologous chondrocyte implantation) is a two-stage cell-culture procedure. In the first stage, cartilage cells are harvested. They are cultured and then implanted in a second procedure. MACI (matrix-induced autologous chondrocyte implantation) is a variant in which the cultured cells are seeded onto a collagen membrane before implantation.

The evidence on whether ACI is better than microfracture is mixed and unresolved.

Osteochondral grafting (OATS — osteochondral autograft transfer / mosaicplasty / allograft)

Osteochondral grafting transplants a unit of cartilage together with its underlying bone, so it suits defects where bone is also involved.

Debridement / chondroplasty

Debridement smooths or removes loose, unstable cartilage edges, typically for mechanical symptoms such as catching or locking.

How the techniques compare

No technique has consistent high-quality evidence of superiority over the others. The evidence base is limited and heterogeneous, and it is dominated by lower-level studies. No technique replaces the defect with true hyaline cartilage. Selection is individualised.

Technique	Best suited to	Stages	Repair tissue/source
Microfracture	Small, contained, full-thickness defects in younger patients with healthy joints	Single	Fibrocartilage from bone marrow cells
AMIC	Microfracture combined with a collagen membrane	Single	Microfracture plus a collagen membrane
ACI / MACI	Defects over 2 cm² in patients meeting NICE (UK) criteria	Two	Cultured cartilage cells
Osteochondral grafting	Defects where bone is also involved	Single	Cartilage plus bone (own tissue or donor)
Debridement / chondroplasty	Mechanical symptoms such as catching or locking	Single	Smoothing of loose cartilage edges

Which technique is best?

No technique is universally best. The evidence comparing them is limited and heterogeneous, and it does not consistently favour any single approach. The right choice depends on the individual, including the size and location of the defect, the condition of the surrounding joint, and the person’s own circumstances. Your surgeon can discuss which approach may suit you after examining your knee.

Recovery and return to activity

Recovery

Recovery and return to activity

Recovery from cartilage repair is measured in months, not weeks, and it depends heavily on the procedure and the defect. No fixed timeline fits every procedure, and the treating team sets the criteria for each stage.

Reported return-to-sport timescales differ by technique. After microfracture, this is typically around 8 to 10 months. After osteochondral autograft (OATS or mosaicplasty), it is around 6 to 9 months. After autologous chondrocyte implantation (ACI), it is around 12 to 18 months, with full maturation of the repair tissue described up to about 2 years. Across studies, roughly 77.2 to 88.2% of athletes returned to play at a mean of about 4.9 to 11.6 months, but these figures come largely from athletic cohorts and the protocols and criteria vary widely.

Weight-bearing is phased after surgery. Partial or protected weight-bearing is commonly recommended for roughly 1 to 4 weeks, progressing to full weight-bearing — typically about 6 to 8 weeks when protected weight-bearing starts later, or about 10 to 12 weeks in two of the three studies that began weight-bearing earlier — though there is no consensus on the optimal schedule. Rehabilitation is led by your physiotherapist and progresses in phases: protecting the repair, restoring movement, rebuilding strength, then a criteria-based return to activity. A calendar date alone does not clear you to resume activity; the treating team sets the criteria based on how your knee is actually recovering.

Why timelines differ from person to person

The wide ranges above reflect genuine differences in procedure, defect size and individual healing. A larger or more complex defect typically takes longer, as does a technique with a longer maturation period such as ACI. Figures drawn from athletic cohorts may not match a less active person’s course. This is why your team will judge progress by criteria rather than by a date on the calendar.

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Risks and limitations

It is important to be clear about what cartilage repair can and cannot do. No current technique regrows true hyaline cartilage, and none has been proven to prevent later osteoarthritis.

Microfracture produces a repair tissue called fibrocartilage whose long-term durability is uncertain; a functional decline is reported in some studies from about 2 to 5 years, though the evidence is conflicting and insufficient to confirm durability. The overall evidence base for cartilage repair is limited and varied. A Cochrane review found insufficient evidence for ACI, and many studies are lower-level case series. Because no technique is consistently shown to be superior, treatment selection is individualised to your situation.

Untreated significant defects can contribute over time to joint degeneration, but progression is not predictable and no individual percentage risk exists. Symptom severity and X-ray appearance correlate poorly, so how the knee looks and how it feels do not always line up. The aim of repair is to relieve symptoms and improve function, not to guarantee a particular outcome.

OrthoKinetics Recovery Reflection

Recovery reflection

If repair tissue is not the same as the cartilage you had, what should you expect from it?

It is natural to hope a repair returns the knee to exactly what it was. The honest position is more measured. No current technique replaces the defect with true hyaline cartilage, and the aim of repair is to relieve symptoms and improve how the knee works. Judging it by that aim, rather than by a perfect result, tends to make the months of recovery easier to carry.

What does it mean to judge your recovery by how the knee is healing, rather than by the calendar?

Recovery from cartilage repair is measured in months, not weeks. A date on the calendar does not clear you to return to activity. Your treating team sets the criteria, so the more useful question is how the knee is actually recovering at each stage.

The aim of cartilage repair is a knee that works better and is more comfortable, not a flawless one, and that aim is what you and your team keep checking as the months go by.

Illustrative image

Meet Dr Sean Leo

A consultant orthopaedic surgeon whose clinical focus is the knee, sports injuries and the lower limb.

Dr Sean Leo is a consultant orthopaedic surgeon. OrthoKinetics is his professional brand; clinical services are provided through OrthoSports Orthopaedic & Sports Surgery at Mount Elizabeth Novena Specialist Centre and Connexion, Farrer Park Hospital.
His clinical interests include sports injuries, including those in adolescent athletes; ligament reconstruction; realignment surgery; cartilage repair and joint-preservation approaches; knee replacement; and technology-assisted hip and knee surgery.
The consistent aim is to return people to meaningful function and activity while avoiding unnecessary downtime.
Qualifications: MBBS, MRCS (Ed), MMed (Ortho), FRCSEd (Ortho).

More detail: Meet Dr Sean Leo

Training and career: Dr Leo trained in medicine at the National University of Singapore and served in the Singapore Armed Forces Medical Corps from 2000 to 2012, where his work included the care of soldiers in physically demanding roles. He completed postgraduate orthopaedic training in 2009 and a one-year clinical fellowship at Royal North Shore Hospital in Sydney, Australia, before joining Changi General Hospital as an orthopaedic consultant in 2012, where he later held the positions of Senior Consultant and Director of the Hip and Knee Service. With seniority, his educational contribution has evolved towards mentorship and support for junior doctors.

About Dr Sean Leo

Dr Sean Leo standing in clinical scrubs against a plain wall — **Dr Sean Leo**Orthopaedic Surgeon · consultations through OrthoSports

Questions people often ask

Common cartilage questions

Can a damaged cartilage be repaired at all?

Repair options exist, but none regrows true hyaline cartilage. Surgery suits specific defects, usually focal and symptomatic ones.

Can knee cartilage repair itself?

Cartilage has limited capacity to heal on its own. A healing response produces fibrocartilage, which is mechanically inferior to native cartilage.

Can I regenerate knee cartilage naturally?

No method, natural or surgical, is proven to regrow true hyaline cartilage. No supplement is proven to reverse damage.

How do I know if my knee cartilage is damaged?

Diagnosis rests on history, examination and MRI. X-ray cannot show cartilage itself, so a normal X-ray does not rule out damage.

Can I repair cartilage without surgery?

Non-surgical care is the first line. It relieves symptoms and improves function but does not regrow cartilage, and many patients improve without surgery.

How long does cartilage repair surgery take to recover from?

Recovery takes months, not weeks, typically 6 to 18 months depending on the procedure. Return-to-sport figures come largely from athletic cohorts.

Does cartilage surgery prevent arthritis?

No procedure is proven to prevent later osteoarthritis. Untreated defects can contribute to degeneration over time, but no individual outcome is guaranteed.

How much does cartilage repair cost in Singapore?

Cost depends on the procedure, graft source, facility and rehabilitation. Cost estimates are provided after consultation, assessment and surgical planning, and are also used to assist with insurance pre-authorisation where applicable.

Knee conditions and knee assessment hub
Meniscus repair surgery
ACL reconstruction surgery (cartilage damage often occurs alongside ligament injuries)
Knee cartilage damage: causes, symptoms and treatment

What do people mean by a “knee specialist”?

“Knee specialist” is an everyday phrase many people use when looking for a doctor for a knee problem. In Singapore, doctors may only use the specialist titles accredited by the Specialist Accreditation Board (SAB) of the Ministry of Health (MOH). Orthopaedic Surgery is an accredited specialty; the knee is an area of clinical interest within it. “Knee specialist” is not a separate specialist registration; however, individual orthopaedic surgeons may have particular clinical interests within their specialty. The doctor most people have in mind is an orthopaedic surgeon whose practice focuses on knee conditions. Dr Sean Leo is registered as a specialist in Orthopaedic Surgery, and his clinical interest is the knee. He completed a postgraduate knee fellowship programme in Sydney, Australia, at the Royal North Shore Hospital under Dr Myles Coolican and Dr David Parker from 2009 to 2010. Dr Leo was also Director of the Hip and Knee Service at Changi General Hospital from 2014 to 2018.

Costs and insurance

Practicalities

Cost, Medisave and insurance

Logos of Great Eastern, HSBC Life, Prudential, Singlife, Alliance Medinet and iXchange, the insurers and corporate health plan administrators on whose panels Dr Sean Leo is listed

The final cost of knee cartilage repair depends on several factors rather than a single figure. These include the type of procedure, such as whether it is a single-stage or two-stage treatment like ACI/MACI, the source of the graft (the patient’s own tissue or donor tissue), facility and centre fees, and the imaging and rehabilitation that surround the operation.

A cost estimate for surgery can be given only after a consultation and assessment, once a surgical plan has been developed. Each individual condition is unique — implants used, time taken, and other factors contribute to the overall estimate. The estimate will be provided to you by the clinic should you decide on surgical management, and will also be used to assist in obtaining pre-authorisation from insurance where applicable.

Insurance panels. Dr Sean Leo, Orthopaedic Surgeon, is on the specialist panels of Great Eastern (GE Panel), HSBC Life (HSBC Life Shield) and Singlife (Singlife Shield), and on the Prudential Panel. AXA Insurance Singapore became part of HSBC Life in 2023, and former AXA Shield plans are now HSBC Life Shield plans.

Corporate health plans. Dr Leo is on the panels of both Alliance Medinet and iXchange, which administer medical benefits for many company health plans. If your company plan uses either panel, you can see Dr Leo as a panel doctor.

If your company uses a different panel. Some company plans still let you see a doctor of your choice outside their panel, then claim reimbursement. This varies from plan to plan, as may the co-payment, so please check your benefits with your company’s HR department.

Panel arrangements change from time to time, so please confirm with your insurer or your company’s plan administrator before your appointment.

Dr Leo is on the panels shown. If your insurer is not listed, you may ask whether co-management with an Orthosports surgeon partner on that panel is clinically and administratively appropriate. Orthosports surgeon partners are collectively on the panels of all Shield plans.

Benefits, pre-authorisation, letters of guarantee, panel rules and reimbursement depend on your individual policy and the insurer’s decision. Neither panel status nor co-management guarantees coverage, approval or cashless treatment. The clinic team can assist with claim paperwork, but cannot promise the outcome.

Arrange a cartilage or knee assessment

Arrange a consultation: the appointment section is further down this page.

Sources

References

NICE. Autologous chondrocyte implantation for treating symptomatic articular cartilage defects of the knee. Technology appraisal guidance TA477. London: National Institute for Health and Care Excellence; 2017.
Vasiliadis HS, Wasiak J. Autologous chondrocyte implantation for full thickness articular cartilage defects of the knee. Cochrane Database of Systematic Reviews. 2010;(10):CD003323. DOI: 10.1002/14651858.CD003323.pub3.
Chahal J, Gross AE, Gross C, et al. Outcomes of osteochondral allograft transplantation in the knee. Arthroscopy. 2013;29(3):575-588. DOI: 10.1016/j.arthro.2012.12.002.
Mithoefer K, McAdams T, Williams RJ, Kreuz PC, Mandelbaum BR. Clinical efficacy of the microfracture technique for articular cartilage repair in the knee: an evidence-based systematic analysis. Am J Sports Med. 2009;37(10):2053-2063. DOI: 10.1177/0363546508328414.
Knutsen G, Drogset JO, Engebretsen L, et al. A randomized trial comparing autologous chondrocyte implantation with microfracture. Findings at five years. J Bone Joint Surg Am. 2007;89(10):2105-2112. DOI: 10.2106/JBJS.G.00003.
Chen X, You M, Liao K, et al. Quantitative Magnetic Resonance Imaging Had Greater Sensitivity in Diagnosing Chondral Lesions of the Knee: A Systematic Review and Meta-analysis. Arthroscopy. 2024;40(11):2760-2773.e14. DOI: 10.1016/j.arthro.2024.01.035.
American Academy of Orthopaedic Surgeons. Articular Cartilage Restoration. OrthoInfo. https://www.orthoinfo.org/treatment/articular-cartilage-restoration/
American Orthopaedic Society for Sports Medicine. Articular Cartilage Injuries. https://www.sportsmed.org/articular-cartilage-injuries
American Academy of Orthopaedic Surgeons. Osteochondritis Dissecans. OrthoInfo. https://orthoinfo.aaos.org/en/diseases–conditions/osteochondritis-dissecans/
Nassar JE, Guerin G, Keel T, Russo R, Familiari F, Tollefson LV, LaPrade RF. Autologous chondrocyte implantation, matrix-induced autologous chondrocyte implantation, osteochondral autograft transplantation and osteochondral allograft improve knee function and pain with considerations for patient and cartilage defects characteristics: A systematic review and meta-analysis. Knee Surg Sports Traumatol Arthrosc. 2025;33(8):2745-2762. DOI: 10.1002/ksa.12525.
Trofa DP, Hong IS, Lopez CD, Rao AJ, Yu Z, Odum SM, Moorman CT 3rd, Piasecki DP, Fleischli JE, Saltzman BM. Isolated Osteochondral Autograft Versus Allograft Transplantation for the Treatment of Symptomatic Cartilage Lesions of the Knee: A Systematic Review and Meta-analysis. Am J Sports Med. 2023;51(3):812-824. DOI: 10.1177/03635465211053594.
Kraeutler MJ, Belk JW, Purcell JM, McCarty EC. Microfracture Versus Autologous Chondrocyte Implantation for Articular Cartilage Lesions in the Knee: A Systematic Review of 5-Year Outcomes. Am J Sports Med. 2018;46(4):995-999. DOI: 10.1177/0363546517701912.
Brittberg M, Recker D, Ilgenfritz J, Saris DBF; SUMMIT Extension Study Group. Matrix-Applied Characterized Autologous Cultured Chondrocytes Versus Microfracture: Five-Year Follow-up of a Prospective Randomized Trial. Am J Sports Med. 2018;46(6):1343-1351. DOI: 10.1177/0363546518756976.
Poole AR. Osteoarthritis as a whole joint disease. HSS J. 2012;8(1):4-6. DOI: 10.1007/s11420-011-9248-6.
Duong V, Oo WM, Ding C, Culvenor AG, Hunter DJ. Evaluation and Treatment of Knee Pain: A Review. JAMA. 2023;330(16):1568-1580. DOI: 10.1001/jama.2023.19675.
Hanaoka C, Fausett C, Jayabalan P. Nonsurgical Management of Cartilage Defects of the Knee: Who, When, Why, and How? J Knee Surg. 2020;33(11):1078-1087. DOI: 10.1055/s-0040-1713813.
Hambly K, Silvers HJ, Steinwachs M. Rehabilitation after Articular Cartilage Repair of the Knee in the Football (Soccer) Player. Cartilage. 2012;3(1 Suppl):50S-6S. DOI: 10.1177/1947603511413569.
Hurley ET, Davey MS, Jamal MS, Manjunath AK, Alaia MJ, Strauss EJ. Return-to-Play and Rehabilitation Protocols following Cartilage Restoration Procedures of the Knee: A Systematic Review. Cartilage. 2021;13(1_suppl):907S-914S. DOI: 10.1177/1947603519894733.
Rolf S, Kwan CK, Stoddart M, Li Y, Fu SC. Timing of postoperative weightbearing in the treatment of traumatic chondral injuries of the knee in athletes — a systematic review of current concepts in clinical practice. Asia Pac J Sports Med Arthrosc Rehabil Technol. 2022;27:1-8. DOI: 10.1016/j.asmart.2022.01.001.

Final next step

Next step

Final next step

Reading about a problem is a starting point. An assessment brings together the history, an examination where needed and any useful tests, and helps you and your clinician decide what to do next. How much physical examination is needed is a matter of clinical judgement. It may be limited when pain makes an examination unreliable, or when imaging clearly shows a problem that matches the symptoms, such as a fracture seen on an X-ray or an MRI scan that clearly shows an injury consistent with the symptoms. The Singapore Medical Council and the UK General Medical Council both allow remote medical consultations, where a physical examination is not possible, with safeguards: the doctor must be clear about the limits of an opinion formed without an examination, and whether an in-person examination is needed, or referral to other services, is left to the clinical judgement of the attending doctor.

Signs that need urgent help

Some symptoms should not wait for a routine appointment. Each item below says where to go.

After an injury

The leg looks twisted or bent, a bone is showing, there is a deep cut, or the foot or leg turns cold, pale, numb, blue or white. Go to an emergency department or call 995.
You cannot lift your leg up with the knee kept straight, and you may feel a gap just above or just below the kneecap. Arrange an urgent same-day assessment.

At any time

The knee is stuck and will not straighten, or it is very painful and you cannot move it or put weight on it. Arrange an urgent same-day assessment.
The knee is suddenly very painful, hot, red and swollen, especially with a fever or feeling generally unwell. Go to an emergency department or call 995.
One calf or thigh is newly painful and swollen. Arrange an urgent same-day assessment. If you also feel short of breath or have chest pain, go to an emergency department or call 995.

After knee surgery

The operated knee becomes more painful, swollen or red, a wound is leaking, or you develop a fever. Go to an emergency department or call 995, or contact your surgical team straight away.

If you are admitted by the doctor at the urgent care centre of one of these private hospitals, the Parkway Pantai hospitals (Mount Elizabeth Orchard, Mount Elizabeth Novena, Gleneagles and Parkway East), Farrer Park Hospital and Thomson Medical Centre, you may ask for Dr Sean Leo to be your attending orthopaedic surgeon. If you are instead discharged and referred for orthopaedic follow-up, you may contact the clinic to arrange an appointment. Both are subject to the hospital’s admission processes and to Dr Leo’s availability.

Arrange a cartilage or knee assessment

Compare cartilage repair techniques

Arrange a consultation

Appointments are arranged through the OrthoSports clinic team. Send your details below, or message or call the clinic.

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WhatsApp is for clinic enquiries only. It is not an emergency service and is not monitored for urgent care. Website or messaging contact is not an emergency-response service. For a medical emergency, use your local emergency service.

OrthoKinetics does not provide emergency or urgent care through this webpage or its WhatsApp contact.

Cartilage repair in brief

What’s covered on this webpage

What is articular cartilage, and how does it get damaged?

Hyaline cartilage: the smooth bearing surface

Traumatic damage vs wear-and-tear degeneration

Articular cartilage is not the meniscus

Can damaged cartilage repair itself?

Symptoms of cartilage damage

Cartilage Wear: Why Early Changes Matter More Than You Think

When should a cartilage problem be assessed?

What does assessment involve?

History and examination

Imaging: what X-ray can and cannot show

MRI (magnetic resonance imaging) and, when needed, arthroscopy

Non-surgical treatment options

Activity modification, weight management and physiotherapy

Injections and medication

Cartilage Damage: Treatment Options at a Glance

When is cartilage repair surgery considered?

Structure / Patient / Goal

Structure: what the defect actually is

Patient: who you are and what you can carry

Goal: what you want to get back to

Cartilage repair techniques

Microfracture / marrow stimulation

AMIC — autologous matrix-induced chondrogenesis (enhanced microfracture)

Autologous chondrocyte implantation (ACI) and matrix-induced ACI (MACI)

Osteochondral grafting (OATS — osteochondral autograft transfer / mosaicplasty / allograft)

Debridement / chondroplasty

How the techniques compare

Which technique is best?

Recovery and return to activity

Risks and limitations

If repair tissue is not the same as the cartilage you had, what should you expect from it?

What does it mean to judge your recovery by how the knee is healing, rather than by the calendar?

A consultant orthopaedic surgeon whose clinical focus is the knee, sports injuries and the lower limb.

Common cartilage questions

Cost, Medisave and insurance

References

Final next step

Arrange a consultation