Osteochondral Grafting and Microfracture Surgery Rehabilitation
What is osteochondral grafting and microfracture surgery?
Articular cartilage — the smooth, glistening tissue that covers the ends of bones within joints — has very limited capacity for self-repair. When cartilage is damaged by injury or disease, the body's natural healing response produces fibrocartilage rather than true hyaline cartilage, and fibrocartilage is significantly inferior in mechanical properties to the original tissue. Osteochondral grafting and microfracture surgery are two different surgical approaches to stimulating cartilage repair in damaged joints, most commonly the knee, with different mechanisms and different rehabilitation implications.
Microfracture surgery involves creating multiple small holes through the calcified cartilage layer into the subchondral bone beneath a cartilage defect. This releases bone marrow cells — including mesenchymal stem cells — into the defect, where they form a blood clot that eventually differentiates into fibrocartilage repair tissue. It is a relatively simple arthroscopic procedure with low surgical complexity, but the quality of the repair tissue (fibrocartilage rather than hyaline cartilage) has functional limitations, and outcomes tend to deteriorate over time in higher-demand patients. It is best suited to smaller defects in younger, lighter patients with low activity demands, or as a bridging procedure before more definitive cartilage restoration.
Osteochondral grafting involves transplanting cartilage and its underlying bone from a donor site to fill a cartilage defect. This can be done as an autograft procedure — using the patient's own cartilage from a lower-load area of the knee (OATS — osteochondral autograft transfer system) — or as an allograft procedure using donor cartilage from a tissue bank. Unlike microfracture, osteochondral grafting transplants true hyaline cartilage, which produces superior long-term biomechanical results for larger defects and higher-demand patients. The rehabilitation is longer and more protective than microfracture, but the quality of the repair is generally better.
Both procedures are most commonly performed in the knee, though they can be applied to other joints including the ankle and hip.
Why is physiotherapy essential after these procedures?
Osteochondral grafting and microfracture surgery require a carefully structured rehabilitation plan to optimise healing, restore joint function, and prevent further injury. The critical principle — which distinguishes cartilage repair rehabilitation from most other post-surgical pathways — is that the repair tissue must be progressively loaded over an extended period to stimulate appropriate maturation, but premature or excessive loading before the repair tissue has sufficiently matured will damage it before it is strong enough to withstand mechanical stress.
The cartilage repair maturation process takes considerably longer than bone healing. Microfracture repair tissue reaches functional maturity at roughly six to twelve months. Osteochondral graft integration — where the transplanted bone and cartilage heal into the surrounding tissue — takes three to six months for the bony component, but the overlying cartilage requires considerably longer to adapt to the mechanical environment. This extended timeline is why cartilage repair rehabilitation is one of the most prolonged post-surgical pathways in orthopaedic physiotherapy.
What does rehabilitation involve?
In the first six weeks, the priority is protecting the repair while preventing the muscle wasting and joint stiffness that accompany immobilisation. Weight-bearing restrictions are typically strict during this phase — for microfracture, non-weight-bearing for six weeks is standard; for osteochondral grafting, protocols vary by surgeon and defect location. Physiotherapy focuses on quadriceps activation, straight leg raises, gentle range-of-motion within permitted limits, and swelling management. Walking unaided typically begins four to six weeks after surgery, depending on progress and weight-bearing guidelines.
From six to twelve weeks, as weight-bearing is progressively introduced, closed-chain strengthening begins — stationary cycling, mini squats, step-ups — alongside gait retraining, balance and proprioception work, and progressive hip and quadriceps strengthening. Real time ultrasound assists in retraining VMO and deep hip stabiliser activation where inhibition from pain and surgery has disrupted normal muscle recruitment.
From three to six months, more demanding functional activities are progressively introduced. Clinical Pilates is particularly valuable during this phase — the reformer allows progressive knee loading through controlled ranges with precise load adjustment, building meaningful strength while respecting the maturation timeline of the repair tissue.
From six to twelve months, returning to sports generally takes six to twelve months, depending on the extent of healing and individual progress. Return to sport is guided by objective strength testing — typically single-leg hop testing and strength symmetry assessment — alongside imaging evidence of repair tissue maturation where available, rather than symptoms or a calendar date alone.
One important clinical consideration is the relationship between defect size and rehabilitation timeline — larger defects treated with osteochondral allograft require more conservative progression than smaller defects treated with microfracture. Your physiotherapist will calibrate the rehabilitation pace to your specific procedure and defect characteristics.
For patients whose cartilage injury occurred in a workplace accident or motor vehicle incident, WorkCover and CTP funded rehabilitation is available.
Our physiotherapists Eliane Machado and Bethany Kippen and have experience in post-surgical knee rehabilitation and are members of the Australian Physiotherapy Association. Eliane's doctoral research in knee biomechanics and cartilage loading is directly relevant to the load management decisions central to cartilage repair rehabilitation.
To book or find out more, call us on 07 3706 3407 or book online below. We see patients from across Brisbane's southside including Tarragindi, Coorparoo, Holland Park, Greenslopes and Mt Gravatt.
Articular cartilage — the smooth, glistening tissue that covers the ends of bones within joints — has very limited capacity for self-repair. When cartilage is damaged by injury or disease, the body's natural healing response produces fibrocartilage rather than true hyaline cartilage, and fibrocartilage is significantly inferior in mechanical properties to the original tissue. Osteochondral grafting and microfracture surgery are two different surgical approaches to stimulating cartilage repair in damaged joints, most commonly the knee, with different mechanisms and different rehabilitation implications.
Microfracture surgery involves creating multiple small holes through the calcified cartilage layer into the subchondral bone beneath a cartilage defect. This releases bone marrow cells — including mesenchymal stem cells — into the defect, where they form a blood clot that eventually differentiates into fibrocartilage repair tissue. It is a relatively simple arthroscopic procedure with low surgical complexity, but the quality of the repair tissue (fibrocartilage rather than hyaline cartilage) has functional limitations, and outcomes tend to deteriorate over time in higher-demand patients. It is best suited to smaller defects in younger, lighter patients with low activity demands, or as a bridging procedure before more definitive cartilage restoration.
Osteochondral grafting involves transplanting cartilage and its underlying bone from a donor site to fill a cartilage defect. This can be done as an autograft procedure — using the patient's own cartilage from a lower-load area of the knee (OATS — osteochondral autograft transfer system) — or as an allograft procedure using donor cartilage from a tissue bank. Unlike microfracture, osteochondral grafting transplants true hyaline cartilage, which produces superior long-term biomechanical results for larger defects and higher-demand patients. The rehabilitation is longer and more protective than microfracture, but the quality of the repair is generally better.
Both procedures are most commonly performed in the knee, though they can be applied to other joints including the ankle and hip.
Why is physiotherapy essential after these procedures?
Osteochondral grafting and microfracture surgery require a carefully structured rehabilitation plan to optimise healing, restore joint function, and prevent further injury. The critical principle — which distinguishes cartilage repair rehabilitation from most other post-surgical pathways — is that the repair tissue must be progressively loaded over an extended period to stimulate appropriate maturation, but premature or excessive loading before the repair tissue has sufficiently matured will damage it before it is strong enough to withstand mechanical stress.
The cartilage repair maturation process takes considerably longer than bone healing. Microfracture repair tissue reaches functional maturity at roughly six to twelve months. Osteochondral graft integration — where the transplanted bone and cartilage heal into the surrounding tissue — takes three to six months for the bony component, but the overlying cartilage requires considerably longer to adapt to the mechanical environment. This extended timeline is why cartilage repair rehabilitation is one of the most prolonged post-surgical pathways in orthopaedic physiotherapy.
What does rehabilitation involve?
In the first six weeks, the priority is protecting the repair while preventing the muscle wasting and joint stiffness that accompany immobilisation. Weight-bearing restrictions are typically strict during this phase — for microfracture, non-weight-bearing for six weeks is standard; for osteochondral grafting, protocols vary by surgeon and defect location. Physiotherapy focuses on quadriceps activation, straight leg raises, gentle range-of-motion within permitted limits, and swelling management. Walking unaided typically begins four to six weeks after surgery, depending on progress and weight-bearing guidelines.
From six to twelve weeks, as weight-bearing is progressively introduced, closed-chain strengthening begins — stationary cycling, mini squats, step-ups — alongside gait retraining, balance and proprioception work, and progressive hip and quadriceps strengthening. Real time ultrasound assists in retraining VMO and deep hip stabiliser activation where inhibition from pain and surgery has disrupted normal muscle recruitment.
From three to six months, more demanding functional activities are progressively introduced. Clinical Pilates is particularly valuable during this phase — the reformer allows progressive knee loading through controlled ranges with precise load adjustment, building meaningful strength while respecting the maturation timeline of the repair tissue.
From six to twelve months, returning to sports generally takes six to twelve months, depending on the extent of healing and individual progress. Return to sport is guided by objective strength testing — typically single-leg hop testing and strength symmetry assessment — alongside imaging evidence of repair tissue maturation where available, rather than symptoms or a calendar date alone.
One important clinical consideration is the relationship between defect size and rehabilitation timeline — larger defects treated with osteochondral allograft require more conservative progression than smaller defects treated with microfracture. Your physiotherapist will calibrate the rehabilitation pace to your specific procedure and defect characteristics.
For patients whose cartilage injury occurred in a workplace accident or motor vehicle incident, WorkCover and CTP funded rehabilitation is available.
Our physiotherapists Eliane Machado and Bethany Kippen and have experience in post-surgical knee rehabilitation and are members of the Australian Physiotherapy Association. Eliane's doctoral research in knee biomechanics and cartilage loading is directly relevant to the load management decisions central to cartilage repair rehabilitation.
To book or find out more, call us on 07 3706 3407 or book online below. We see patients from across Brisbane's southside including Tarragindi, Coorparoo, Holland Park, Greenslopes and Mt Gravatt.
