Knee treatments & procedures
Osteotomies around the knee
The word describes the cutting of bone. This simple procedure is a tried and tested technique in orthopaedics. It is used to straighten deformed bones and to alter the line of weight bearing through an arthritic joint to provide pain relief.
Osteotomy is used only on patients who are too young for knee replacement surgery.
In young children and adolescents, there are conditions which give rise to quite severe knock knees or bow legs. In such cases, osteotomy is employed to straighten the legs.
Osteotomies around the knee are done either on the femur or thigh bone above the knee or in the tibia or shin bone below the knee. The required amount of correction can be determined prior to surgery.
A small incision is made over the part of the bone to be treated. The bone is exposed and using a very fine saw the bone is cut across. Once cut and repositioned the bone is 'set' in place using a plate and tiny screws.
Alternatively a slice of bone is removed and then the two edges are brought together. Again this is set with a plate and screws or sometimes a small staple. Full recovery generally takes 6 weeks to 3 months.
A plaster cast may be applied to the limb following the operation. Often a plaster is not used. This also allows the knee to start moving as soon as possible to prevent arthritic symptoms.
Anterior Cruciate Ligament Replacement
The knee joint is supported by four ligaments - two outside the knee joint and two inside. The inside the knee joint are called the anterior and the posterior cruciate ligaments.
These ligaments provide stability to the knee joint. Specifically, the main function of the anterior cruciate ligament (ACL) is to prevent the knee from 'giving way'.
The ligament is often damaged during sporting activities which involve the foot being fixed onto the ground and the body twisting - causing the ligament to rupture. Typical scenarios involve skiing, football or rugby. When the ligament ruptures, a crack or a pop is heard and the knee gives way and swells quickly.
It is difficult to bear weight at the knee joint. After the trauma it is best to allow the knee to rest completely, apply an elasticated stocking and to take pain relief medication.
An x-ray is taken to ensure that there are no other bone injuries or fractures. Once this acute phase has passed the knee can be thoroughly examined. An MRI scan is often employed to assess the status of the cartilage, ligaments and soft tissues.
Occasionally arthroscopy (keyhole surgery) may be required to give a clearer picture of the damage sustained. Once the diagnosis has been confirmed physiotherapy is recommended. If the knee continues to present problems it is appropriate to consider surgery.
The operation involves three stages. A graft which will be used as the new ACL. The second stage is preparation of the knee for insertion of the graft. This procedure is carried out arthroscopically (keyhole surgery). The final stage consists of inserting the graft using screws or special pins. The operation usually takes about 40-60 minutes and assessment of the other structures in the knee is also made at the same time.
Finally the wound is dressed and an ice pack is applied. Physiotherapy will usually commence within 24 hours of surgery. CPM (continuous passive motion) is also commenced within 24 hours of surgery. This consists of placing the leg into a machine which assists in extending and flexing the knee. The hospital stay is usually between 1 to 3 days but ultimately depends upon the patient's circumstances and the surgeon's advice.
A great deal of success of the reconstruction depends upon the subsequent post-op physiotherapy. This can last 6-9 months and only at the end of this period is one able to participate in sports such as football, rugby or skiing.
Meniscectomy
The menisci act as 'shock absorbers' between the long bones making up the knee. They are made fibrous material. The majority of the meniscus does not have a blood supply and it is for this reason that healing of these tissues once damaged is practically impossible.
Damage to the meniscus is an extremely common condition that can occur during practically any form of activity. Symptoms are pain felt along the inside or outside aspect of the knee depending on which cartilage has been torn. Often pain may appear to subside, only to return later.
Twinges upon movement of the knee, a sense of 'giving way' within the knee and inability to fully straighten the leg are other indications.
Meniscectomy is the surgical removal of all or part of a damaged meniscus. This is one of the most common procedures performed in the UK using a technique referred to as arthroscopy (keyhole surgery).
A small camera is inserted into a small incision at the front of the knee. This allows the whole of the knee to be fully inspected.
MRI scans will show whether a meniscus is torn and on that basis a decision can be taken about the need for surgery. There is never an absolute need for surgery, however in over 90% of cases surgery will be effective.
A small incision is made into the knee, and a fibre optic telescope instrument is used to view the internal cavity. The surgeon will only remove the damaged portion of the cartilage retaining the cushion function of the cartilage.
Recovery time varies between 2 and 6 weeks. Post surgery, the patient should be returning to normal activity. Sporting activity can be resumed after approximately one month.
Total knee replacement
One of the most common procedures used in joints that have become stiff and painful and significantly damaged by arthritis and where loss of mobility and loss of function are present.
The objective is to re-line the damaged surface of the joint using a plate placed into the shinbone and a metal sleeve which is placed over the lower end of the thighbone. High density polyethylene decreases friction between the two metal plates.
The main reason for surgery is pain relief and enhanced mobility. The procedure takes up to two hours under a full general anaesthetic or with a spinal anaesthetic in which numbs the lower part of the body.
Following surgery the patient is rested for 24 hours after which the knee can be bent. The patient is usually able to walk with a frame or crutches. Over the following week the patient slowly increases the amount of knee movement exercises and by 7 to 10 days afterwards, the patient is able to walk reasonable distances and is able to walk up and down stairs.
Physiotherapy as an outpatient should normally continue for around 3 months.
Chondral damage
The articular cartilage covers the bony surfaces within the knee joint. Assessment of articular cartilage is made x-rays and / or an MRI scan. If the condition of the knee remains unclear, arthroscopic (keyhole surgery) assessment is a good way of assessing the condition of the articular cartilage.
Surgery may be required in cases of severe pain, locking or swelling and to prevent later osteoarthritic progression in the knee.
Surgical options are:
Arthroscopy and debridement
Microfracture
Autologous chondrocyte implantation
Chondral grafting
Allograft
Osteotomy
Knee Replacement
Multi-ligament injury to the knee
Major multiple ligament injuries to the knee are relatively rare. It is however not uncommon to have a minor injury to another ligament, particularly to the medial collateral ligament. This is common amongst ski injuries. The majority of these sprains will heal without surgery. If there is an excessive laxity in the ligaments, bracing is beneficial.
When two or more ligaments have a serious injury then the knee joint has usually dislocated at the time of injury. Often it immediately springs back into place.
These type of injuries can be limb threatening if the artery adjacent to the knee is torn and emergency surgery is required to re-establish blood supply to the leg below the knee. It is not uncommon for the major nerves that cross the knee to be damaged.
Early surgery is beneficial in that it offers the opportunity for repairing ligaments rather than having to reconstruct them with tendon grafts later.
Many of these injuries, if treated early can result in a good level of mobility. Our advice is that patients should avoid running and or sports to help protect the knee in the long term. The risk of minor complications such as stiffness is high and many patients will require either a manipulation under anaesthetic for stiffness or an arthroscopy.
It takes approximately 18 months to 2 years to achieve final recovery. The most arduous period is in the first 3 to 6 months. The knee will require bracing for 6 to 12 weeks and an intensive physiotherapy work.