Knee Conditions
Knee Arthritis/Osteoarthritis
Arthritis, or degenerative osteoarthritis, of the knee is caused by long term wear and tear to the cartilage that naturally cushions the knee joint. This causes the bones in the joint to rub together and cause permanent damage. This is the most common form of arthritis. In some cases, arthritis can also be triggered – or made worse – by a knee injury that damages a particular area – this is known as ‘traumatic osteoarthritis’ and can often happen as a result of sporting activities.
Although knee arthritis can affect anyone, there are several factors that can increase the risk of arthritis:
These would normally include:
A detailed history about your symptoms and functional disability is required. Additionally, a physical examination will check for tenderness, stiffness and limitation in the range of motion, swelling, gait impairment.
The diagnosis will also include x-rays of the knee looking for looking for loss of joint space between the bone and for joint alignment. Additional investigations such as EOS scan, CT scan or MRI scan may also be required to either exclude other conditions or quantify the degree of arthritis.
Treatment might include nonsurgical treatments, injections and surgery such as:
Knee articular cartilage injuries
Within the knee joint, the articular cartilage acts as a shock absorber that cushions the bones and allows them to move smoothly. This articular cartilage can be acutely injured during sports such as tennis, soccer, skiing or rugby. It is more common in the younger age group.
Compared with arthritis which is usually a result of long-term degeneration and has a more widespread involvement of the joint, articular cartilage injuries occur after known traumatic episodes and tend to focally involve the joint surface. This is important with respect to treatment options available for this condition.
If a fragment of cartilage is damaged or breaks away, it can cause:
In most cases, apart from thorough history and clinical examination, MRI scan and alignment X-rays are required to diagnose the condition, quantify the severity of the injury and formulate a treatment plan.
The treatment options depend on a number of factors including: size of damaged cartilage, impact on daily activities, age, pre-existent knee injury/disability, alignment of the leg.
ACL Tears
The ACL is one of the main stabilising ligaments in the knee, connecting the femur to the tibia. ACL injuries are increasingly common, particularly during pivoting sports such as soccer, tennis, netball, rugby and skiing, and currently affect an increasing number of children and adolescents.
The ACL is in the middle of the knee and controls rotation as well as the forward movement of the tibia bone on the femur bone. If it’s torn, the knee becomes unstable when it is twisted and can give way, as well as losing its full range of movement.
When the ACL tears (ruptures) there is often a popping sound, as well as pain and swelling in the knee, usually within an hour of the injury. Patients usually are unable to continue playing sports and hobble for a week or so and then things can settle down.
In around 20% of cases, people with an ACL tear can continue with normal activities. However, most people have ongoing symptoms including knee instability (where the knee gives way, especially when you change direction while walking or running) as well as recurrent pain. Recurrent episodes of knee instability can lead to injuries to the articular cartilage and/or the menisci. Having early treatment can prevent further damage being caused to these tissues each time the knee gives way.
A detailed history about your symptoms and functional disability is required. Additionally, a physical examination will check for tenderness, limitation of the range of motion and knee instability.
The diagnosis will also include x-rays of the knee, an EOS scan to assess the alignment of the lower limb and an MRI scan to confirm the ACL tear and assess for any other associated injuries.
Initial treatment following the injury includes resting the joint, use of ice packs, applying soft knee braces for compression and joint support and elevation. Early physiotherapy review is important to address the swelling, improve the movement and restore muscle function. Protected weight bearing with crutches may be required in the early stages for pain relief and protection of the joint.
The definitive treatment options depend primarily on the presence of knee instability, associated tissue injuries, level of activities and expectations.
As the knee gives way, the joint surface and meniscal cartilages, frequently become damaged. In 75% of ACL injuries associated damage to the anterolateral ligament or the menisci are encountered. Bruising (oedema) of the bones also occurs at the time of the injury as the femur and tibia collide with each other. The “bone bruising” which is frequently described as micro trabecular fracture does not require any specific treatment.
Mechanism of Injury – The ACL is often injured when the knee is suddenly twisted, for example when a soccer or tennis player changes direction. Another common mechanism is by knee hyperextension (over straightening the joint). Injuries are also common in sports where participants:
Medial Collateral Ligament (MCL) tears
The collateral ligaments of the knee joint are tissue structures that lie outside the joint and provide side-to-side stability to joint. The medial collateral ligament (MCL) runs along the inner side of the knee between the femur and the tibia and provides stability to the inner side of the joint. The lateral collateral ligament (LCL) runs along the outer side of the knee between the femur and the fibula head and provides stability to the outer side of the joint.
The MCL is one of the most commonly injured ligament. The injury is frequently caused by contact to the outer side of the knee and leads to the knee buckling inwards which leads to a varied spectrum of injuries from sprain to partial tear and full tear of the MCL. In comparison, the LCL injuries are rare.
Symptoms include:
Most MCL injuries are diagnosed clinically on the basis of injury description and clinical examination. During the clinical examination, assessment of the laxity of the MCL by lateral (valgus) stress provides information on the grade of laxity and required management.
An MRI scan may be required to accurately diagnose the injury and look for associated injuries such as ACL tears.
This depends on how severely the ligament has been damaged, and whether other ligaments are also affected. If only the MCL is damaged, it is usually possible to treat it without surgery using a simple knee brace that holds the knee in a bent position for 4-6 weeks.
However, if the tear is serious (ligament is pulled off the tibia bone) or other ligaments are affected, surgical treatment with either augmented repair or reconstruction may be required.
Meniscal tears
There are two meniscal cartilages in the knee that act as shock-absorbers – one on the inner (medial meniscus) and one on the outer (lateral meniscus) side.
They are made up of a different type of cartilage to joint surface cartilage and sit between the femur and the tibia.
The menisci have a number of important functions within the knee:
The typical symptoms of a meniscal tear are:
A patient with a meniscal tear may not necessarily experience all these symptoms but can have any combination of the above.
The diagnosis involves a thorough history and clinical examination to assess for all the symptoms and signs of a meniscal tear.
The knee is also assessed for possible associated pathologies such as ligament tears and arthritis. As part of the assessment, x-rays will be required to assess for knee arthritis and, in addition, an MRI scan may need to be done to specifically assess the soft tissues such as the meniscus, articular cartilage and knee ligaments.
Initial treatment following the meniscal tear is based on the RICE protocol: rest, ice, compression, elevation. Additionally, simple analgesia with Paracetamol and/or non-steroidal anti-inflammatories may be required. Early physiotherapy review is important to address the swelling, improve the movement and maintain muscle function.
Loss of meniscal tissue means that there is uneven weight distribution and force between the joint surfaces in the knee, which can lead to arthritis.
Mechanism of Injury – Meniscal tears are among the most common injuries seen by an Orthopaedic Surgeon. The meniscal cartilages are at risk of tearing due to their constant exposure to repetitive loading during activities such as walking and running. In younger patients, meniscal tears normally occur as a result twisting on a loaded flexed knee with the knee then giving way. The giving
Patella dislocation
The patella, also known as the “kneecap” sits at the front part of the knee and articulates with the groove at the front of the femur called the “trochlear groove”. This groove accommodates the patella so that it moves in a straight line as the knee bends. A patella dislocation occurs when the patella comes out of the “trochlear groove”, coming to rest on the outside of the joint.
Causes
Patella dislocation can be caused multiple factors. These factors can be involved either solely or in combination.
Patients who have dislocated their kneecap may experience:
A patella dislocation, especially the first episode, is usually diagnosed clinically either by the attending paramedics or by the attending doctor. An accurate assessment of the injury combined with a physical examination is usually all that is required to diagnose a dislocated patella. In some circumstances, an X-ray of the knee may be performed for diagnosis.
Once the patella is repositioned in its usual location an X-ray is usually taken to confirm the reduction of the patella dislocation and to assess for possible loose bony fragments in the joint. An MRI may also be required to assess for injuries to the articular cartilage. Once the knee has at least been partially rehabilitated further investigations to assess for bony abnormalities and predisposition for further patella dislocations are usually performed. These may include alignment X-rays or an EOS, computer tomography (CT) or weightbearing CT scans and an MRI if it hadn’t already been performed. An EOS is an advanced 2D/3D imaging scan that assesses functional patient positioning, skeletal alignment which assists formulating treatment strategies and surgical plans.
After the first episode of patella dislocation, the treatment is initially based on the RICE principles: rest, ice, compression and elevation. A knee splint and crutches may be required for a few days to allow for the pain and selling to subside. As soon as symptoms allow, a rehabilitation program under the guidance of a physiotherapist is required.
The aims of physiotherapy are to reduce swelling, restore normal joint motion, restore strength of quadriceps muscle, especially its main inner portion, the vastus medialis oblique (VMO) muscle. The physiotherapist may also recommend stretching exercises of hamstring muscles and the iliotibial band. Occasionally taping of the patella into place may help relieve or reduce the chance of ongoing symptoms.
As the knee function improves and symptoms allow the advanced diagnostics scans mentioned above are performed to evaluate for predisposing factors for patella instability. If the scans are normal physiotherapy and sports education programs may be all that is required for restoration of full function. If the scans are abnormal and particularly if you experience further episodes of instability, surgical treatment may be indicated. The management of patella dislocation has changed in recent times and some surgeons are recommending preventative surgery after the first patella dislocation. This is because repeated dislocations can damage cartilage, leading to an increased risk of arthritis. Depending on the abnormalities found surgical procedures can include one or more of the following: reconstruction of the medial patellofemoral ligament (MPFL), tibial tubercle realignment, realignment of the femoral bone to correct abnormal twisting of the femur or to correct a knocked knee deformity.
Anterior knee pain / chondromalacia patellae
Anterior knee pain also known as “patellofemoral pain syndrome” or “chondromalacia patellae” refers to pain arising from the front part of the knee. This occurs when there is an overload on the joint between the back of the knee cap (patella) and the front of the femur
(trochlea groove). As the knee bends and then straightens, the patella glides over the groove at the front of the femur (trochlea groove). Normally the movement of the patella in this groove is smooth and painless. Abnormal movement of the patella in the trochlea groove causes an overload on the patella with resultant pain. Long-term persistent abnormal movement and abnormal load can lead to degeneration in the joint between the patella and the trochlea groove leading to osteoarthritis.
Causes
Some patients develop patellofemoral pain syndrome in the absence of any bone, joint or soft tissue abnormalities. However, most patients with the syndrome present with one or more abnormalities related to bone anatomy, joint anatomy and/or soft tissue.
Patients with patellofemoral pain may experience:
Patellofemoral pain syndrome is a condition that is poorly understood by many orthopaedic surgeons. Many patients have their symptoms dismissed and they are advised to modify their activities, use shoe inserts, attend physiotherapy despite lack of improvement with these measures. Dr Razvan Stoita is an experienced orthopaedic knee surgeon with specific expertise in the assessment and management of patients with anterior knee pain.
The assessment of the condition begins with a detailed history of the symptoms, precipitating factors, aggravating and relieving factors, functional disability, treatment modalities to date. A comprehensive clinical examination is then performed assessing for:
Following this, a batch of radiologic investigations may be required:
In an acute episode of anterior knee pain, the treatment is initially based on the RICE principles: rest, ice, compression and elevation. Crutches may be required for a few days to allow for the pain and selling to subside. As soon as symptoms allow a rehabilitation program under the guidance of a physiotherapist is required.
The aims of physiotherapy are to reduce swelling, restore normal joint motion, restore strength of quadriceps muscle, especially its main inner portion, the vastus medialis oblique (VMO) muscle. The physiotherapist may also recommend stretching exercises of hamstring muscles and the iliotibial band. Occasionally taping of the patella into place may help relieve or reduce the chance of ongoing symptoms. In a few patients, particularly patients that experience anterior knee pain after knee trauma this may be all that is required to address the symptoms and allow return to full function.
Most patients that experience recurrence of symptoms with minimal or no trauma require investigations to assess for abnormalities predisposing to patellofemoral pain syndrome. Depending on symptoms, abnormalities identified and status of articular cartilage on the patella and trochlea groove surgical intervention may be required. The surgical procedures used to treat patellofemoral pain syndrome may include one or more of the following:
Isolated knee arthroscopy with smoothening of the articular cartilage or lateral release has not shown any long-term benefit in numerous clinical studies and is not recommended. Dr Razvan Stoita will discuss with you at length the factors responsible for your symptoms and the recommended treatment.
