What Is Involved in Microfracture Rehabilitation?

Microfracture rehabilitation follows microfracture surgery, a technique which stimulates the growth of new cartilage over bones inside a joint. During the surgery many small holes, or microfractures, are created in bone, allowing the bone marrow, with its associated stem cells, to escape and form new cartilage on the joint surface. Microfracture rehabilitation is an important part of the cartilage regeneration process. While the specific program will vary, most patients will use a continuous passive motion machine and carry out an exercise regime, involving limited weight-bearing on the affected limb. Continuous passive motion (CPM) machines take joints through a range of movements in a controlled manner, and are typically used at home for several hours each day.

Typically, the continuous passive motion machine rests on the patient's bed and the knee is placed inside it. During microfracture rehabilitation, a hand-held controller is used to operate the machine, which repeatedly bends and straightens the knee joint. The machine moves the knee slowly and the patient uses the controls to increase, gradually, the angle at which the joint is bent.

A continuous passive motion machine may be installed in a patient's home prior to surgery so it can be used immediately after the operation. This type of microfracture rehabilitation may be used after fractures have been made in the lower end of the thigh bone, or femur, and the upper end of the shin bone, or tibia. It can also be used after femur and patella surgery, where microfractures encourage new cartilage growth in the area where the patella, or knee bone, slides over the surface of the femur.

When microfracture rehabilitation follows knee surgery with femur and patella fractures, a brace is normally worn which limits how far the knee joint bends. This prevents the regenerating surfaces from pressing together and disturbing the bone marrow while new cartilage forms. The brace is removed only when using the continuous passive motion machine. Using the brace, weight is gradually placed on the leg until the knee joint can support the leg while walking. Exercises are carried out with the brace in position.

After surgery involving the femur and tibia, microfracture rehab involves using crutches for several weeks, but no brace is required. Only a little weight is placed on the leg while exercising. Shallow knee bends may be performed soon after the operation, with stationary cycling and exercises in water being introduced after a week or so. Later, when the leg can bear weight, more strenuous exercises can be used.