Keyhole surgery on the knee is one of the most commonly performed orthopaedic procedures in Australia. Despite how frequently it is done, many patients go into the procedure with only a vague understanding of what actually happens. This article explains what knee arthroscopy involves, what conditions it can treat, and what the recovery period looks like.
What is knee arthroscopy?
Knee arthroscopy is a minimally invasive surgical technique in which a small camera called an arthroscope is inserted into the knee joint through a small incision, typically half a centimetre long. A second incision of similar size is made for the surgical instruments. The camera transmits a live image of the inside of the joint to a monitor, allowing the surgeon to see and treat pathology without opening the knee.
Sterile fluid is pumped into the joint during the procedure to expand the space and improve visibility. The surgeon can move the camera and instruments to assess all parts of the joint systematically and perform the required treatment.
What conditions does it treat?
Knee arthroscopy is used to treat a range of conditions including meniscal tears, cartilage lesions, loose bodies within the joint, ligament injuries and inflammatory conditions such as synovitis. It is also used in the management of certain paediatric knee conditions including discoid meniscus and osteochondritis dissecans.
Meniscal tears are the most common indication. The menisci are two C-shaped cartilage structures that act as shock absorbers within the knee. When a meniscus tears, it can cause pain, swelling and mechanical symptoms such as locking or catching. At arthroscopy, the torn portion is either repaired using sutures or, where repair is not possible, trimmed to remove the unstable fragment.
What happens on the day?
Knee arthroscopy is performed under general or regional anaesthesia and typically takes 30 to 60 minutes depending on the procedure. The patient is admitted on the day of surgery and, in the majority of cases, goes home the same day once comfortable, able to mobilise with crutches, tolerating fluids and able to pass urine.
After surgery, a dressing is applied to the knee and an ice pack is used to manage swelling. Crutches are provided and used for a period that depends on the specific procedure performed.
What does recovery involve?
Physiotherapy begins within the first week following surgery. The initial focus is on reducing swelling, restoring range of motion and reactivating the quadriceps muscles. As recovery progresses, the programme shifts to strengthening and a graduated return to activity.
For most patients, return to office-based work is possible within one to two weeks. Return to more physically demanding work and sport depends on the procedure performed and the demands of the activity. Following a meniscal trim, most patients return to sport within four to six weeks. Following a meniscal repair, which requires the tissue to heal, return to sport typically takes three to four months.
Is knee arthroscopy always the right answer?
Knee arthroscopy is an effective tool for specific structural problems inside the joint, but it is not appropriate for all knee conditions and it does not treat osteoarthritis. Evidence shows that arthroscopy for knee arthritis in the absence of specific mechanical symptoms such as locking does not produce better outcomes than non-surgical management. Mr Balakumar discusses the likely benefit of any procedure clearly at the consultation so that patients can make an informed decision about whether to proceed.
