Hip Knee Shoulder Joint Replacement Surgery

Home >> Consumer/ Patient info >> Conditions & Procedures >> Knee Arthroscopy

Back to Knee Topics

Knee Arthroscopy

The arthroscope is a fibre-optic telescope that can be inserted into a joint
(commonly the knee, shoulder and ankle) to evaluate and treat a number of
conditions .A camera is attached to the arthroscope and the picture is visualized
on a TV monitor. Most arthroscopic surgery is performed as a Day-Only procedure
and is usually done under general anaesthesia. Knee arthroscopy is a common procedure and over 100 000 arthroscopies are performed in Australia each year.

Arthroscopy is useful in evaluating and treating the following conditions

1. Torn floating cartilage (meniscus): The cartilage is trimmed to a stable rim or occasionally repaired

2. Torn surface (articular) cartilage

3. Removal of loose bodies (cartilage or bone that has broken off) and cysts.

4. Reconstruction of the Anterior Cruciate ligament

5. Patello-femoral (knee-cap) disorders

6. Washout of infected knees

7. General diagnostic purposes

Basic Knee Anatomy

The knee is the largest joint in the body. The knee joint is made up of the femur,
tibia and patella (knee cap). All these bones are lined with articular (surface
cartilage). This articular cartilage acts like a shock absorber and allows a smooth
low friction surface for the knee to move on. Between the tibia and femur lie two floating cartilages called menisci. The medial (inner) meniscus and the Lateral
(outer) meniscus rest on the tibial surface cartilage and are mobile. The menisci
also act as shock absorbers and stabilizers. The knee is stabilized by ligaments
that are both in and outside the joint. The medial and lateral collateral ligaments support the knee from excessive side-to-side movement. The (internal) anterior
and posterior cruciate ligaments support the knee from buckling and giving way.
The knee joint is surrounded by a capsule (envelope) that produces a small
amount of synovial (lubrication) fluid to help with smooth motion. Thigh muscles
are important secondary knee stabilizers.

Investigations:

A routine X-Ray of the knee which includes a standing weight-bearing view is
usually required. An MRI scan which looks at the cartilages and soft tissues may
be needed if the diagnosis is unclear. There is little value in the use of Ultrasound
in investigating knee problems.

Meniscal Cartilage Tears:

Following a twisting type of injury the medial (or Lateral) meniscus can tear. This results either from a sporting injury or may occur from a simple twisting injury
when getting out of a chair or standing from a squatting position. Our cartilages become a little brittle as we get older and therefore can tear a little easier. The symptoms of a torn cartilage include

Pain over the torn area i.e. inner or outer side of the knee
Knee swelling
Reduced motion
Locking if the cartilage gets caught between the femur a tibia

CARTILAGE TEARS

Once a meniscal cartilage has torn it will not heal unless it is a very small tear
which is near the capsule of the joint. Once the cartilage has torn it predisposes
the knee to develop osteoarthritis (wear and tear) in 15 to 20 years. It is better to remove torn pieces from the knee if the knee is symptomatic.

Torn cartilages in general continue to cause symptoms of discomfort, pain and
swelling until the loose, ragged pieces are removed. Only the torn section is
removed and the knee should recover and become symptom free. If the entire meniscus is removed, the knee will develop osteoarthritis in 15 to 20 years.
Now-days only the torn section is removed and it is hoped that this will delay the
onset of long-term wear and tear osteoarthritis.

Occasionally, provided the knee is stable and the tear is a certain type of tear in a young patient (peripheral bucket handle tear), the meniscus may be suitable for
repair. If repaired one has to avoid sports for a min of three months.

Articular Cartilage (Surface) injury:

If the surface cartilage is torn, this is most significant as a major shock-absorbing function is compromised. Large pieces of articular cartilage can float in the knee (sometimes with bone attached) and this causes locking of the joint and can cause further deterioration due to the loose body floating around the knee causing further wear and tear. Most surface cartilage wear will ultimately lead to osteoarthritis. Mechanical symptoms of pain and swelling due to cartilage peeling off can be helped with arthroscopic surgery.
The surgery smoothes the edges of the surface cartilage and removes loose bodies.

Anterior Cruciate Ligament Injuries:

Rupture of the Anterior (rarely the posterior) Cruciate Ligament (ACL) is a
common sporting injury.
Once ruptured the ACL does not heal and usually causes knee instability and the inability to return to normal sporting activities. An ACL reconstruction is required
and a new ligament is fashioned to replace the ruptured ligament. This procedure is performed using the arthroscope.

Patella (knee-cap) disorders:

The arthroscope can be used to treat problems relating to kneecap disorders, particularly mal-tracking and significant surface cartilage tears. Patients may need
to stay overnight if a lateral release has been performed as knee swelling is quite common. The majority of common knee -cap problems can be treated with physiotherapy and rehabilitation

Inflammatory Arthritis:

Occasionally arthroscopy is used in inflammatory conditions (e.g. Rheumatoid
Arthritis) to help reduce the amount of inflamed synovium (joint lining) that is producing excess joint fluid. This procedure is called a synovectomy. After the
surgery a drain is inserted into the knee and patients generally require one or two nights in hospital.

Bakers cysts:

Bakers cysts or popliteal cysts are often found on clinical examination and
ultrasound / MRI scan. The cyst is a fluid filled cavity behind the knee and in
adults arises from a torn meniscus or worn articular cartilage in the knee. These
cysts usually do not require removal as treating the cause (torn knee cartilage)
will in most cases reduce the size of the cyst. Occasionally the cysts rupture and
can cause calf pain. The cysts are not dangerous and do not require treatment if
the knee is asymptomatic.

NEW TECHNOLOGY

Isolated areas of articular cartilage loss can be repaired using cartilage transplant technology. This is a new and exciting field that is developing in the treatment of specific isolated cartilage defects in younger patients

The process is called Autologous Chondrocyte Grafting. It involves harvesting cartilage cells from the affected knee, sending these cells to a laboratory and then culturing the cells to multiply into many cells. The large amount of cells produced
are then placed back into the affected knee into the defect requiring resurfacing. Results are still short-term follow-up but are looking encouraging.

After a major cartilage or ligament injury has been treated the knee can return
to normal function. There is however a small increase in the risk of developing
long-term wear and tear (Osteoarthritis) and depending on the degree of injury
activity modification may be required. Activities that help prevent knees
deteriorating quickly include:

Low impact sports like swimming, cycling and walking
Reducing weight and maintaining a healthy diet

Arthroscopy of the knee: Patient Information

Please stop taking Aspirin and Anti-inflammatories 5 days prior to your surgery.
If pain medication is required use Panadol / Panadine or Panadine Forte. You can continue taking all your other routine medication. If you smoke you are advised
to stop a few days prior to your surgery.

You will be admitted on the day of surgery and need to remain fasted for 6 hours
prior to the procedure.

The limb undergoing the procedure will be marked and identified prior to the anaesthetic

Once you are under anaesthetic, the knee is prepared in a sterile fashion. A
tourniquet is placed around the thigh to allow a ‘blood – free’ procedure.

The Arthroscope is introduced through a small (size of a pen) incision on the outer
side of the knee. A second incision on the inner side of the knee is made to
introduce the instruments that allow examination of the joint and treatment of the problem.

Post-operative recovery

You will wake up in the recovery room and then be transferred back to the ward

A bandage will be around the operated knee.

Once you are recovered your drip will be removed and you will be shown a
number of exercises to do.

Your Surgeon will see you prior to discharge and explain the findings of the operation and what was done during surgery.

Pain medication will be provided and should be taken as directed

You can remove the bandage in 24 hours and place waterproof dressings (provided) over the wounds.

It is NORMAL for the knee to swell after the surgery. Elevating the leg when you
are seated and placing Ice-Packs on the knee will help to reduce swelling. (Ice
packs on for 20 min 3-4 times a day until swelling has reduced)

You are able to drive and return to work when comfortable unless otherwise
instructed

Please make an appointment 7-10 days after surgery to monitor your progress
and remove the 2 stitches in your knee.

Risks of Arthroscopy:

General Anaesthetic risks are extremely rare in Australia. Occasionally patients
have some discomfort in the throat as a result of the tube that supplies oxygen
and other gasses. Please discuss with the Specialist Anaesthetist if you have any specific concerns

Risks related to Arthroscopic knee surgery include:

Postoperative bleeding
Deep Vein Thrombosis
Infection
Stiffness
Numbness to part of the skin near the incisions
Injury to vessels, nerves and a chronic pain syndrome
Progression of the disease process

The risks and complications of arthroscopic knee surgery are extremely small.
One must however bear in mind that occasionally there is more damage in the
knee than was initially thought and that this may affect the recovery time. In
addition if the cartilage in the knee is partly worn out then arthroscopic surgery
has about a 65% chance of improving symptoms in the short to medium term but
more definitive surgery may be required in the future. In general arthroscopic
surgery does not improve knees that have well established Osteoarthritis.

Post –Operative Exercises and Physiotherapy

Following your surgery you will be given an instruction sheet showing exercises
that are helpful in speeding up your recovery. Strengthening your thigh muscles (Quadriceps and Hamstrings) is most important. Swimming and cycling (stationary
or road) are excellent ways to build these muscles up and improve movement.

Frequently asked questions:

How long am I in Hospital?

A: Approx 4 hours

Do I need crutches

A: Usually not required (Unless having Anterior Cruciate Ligament Reconstruction)

When can I get the knee wet

A: After 24 hrs remove the bandage and apply waterproof dressing

When can I drive

A: After 24 hrs if the knee is comfortable

When can I return to work

A: When the knee feels reasonably comfortable

When can I swim