ANTERIOR CRUCIATE LIGAMENT INJURY
The anterior and posterior cruciate ligaments are important stabilizers of the knee joint to allow movement. The Anterior Cruciate Ligament (ACL) is commonly injured during sporting activities. It is usually a result of a twisting injury and some patients may be able to feel a 'pop' sound in the knee as the ligament ruptures. This is usually followed by immediate knee swelling. ACL injury generally prevents any further participation in the sport due to pain. Following injury, the patient may feel as if the knee is giving way which can lead to hesitation in running and jogging.
Doctors initially treat this by immobilizing the knee in a splint (a device to restrict movement in the affected area) after applying a compression bandage. Patients will also be prescribed ice therapy, pain killers and provided with crutches for support. Physical therapy will be recommended to regain movement of the knee.
• X-rays are generally not helpful in diagnosis unless the injury is at the ends of the ligament when there is a possibility of it pulling a chip of bone with it.
• An MRI scan helps confirm the diagnosis and also helps to diagnose injury to other structures in the knee joint.
Physical therapy will be started to strengthen the muscles around the knee joint which may help stabilize the joint. Younger and more active individuals may be recommended surgery in the form of ACL reconstruction. Studies have shown that the ACL does not heal simply by repairing the torn ends together. Surgery is commonly performed by key-hole surgery called arthroscopy, which is a non-invasive surgery but can also be done by an open technique. Reconstruction is generally performed by substituting the ACL with another tendon which may either by taken from the patient himself/herself or from other sources. These tendons used for the reconstruction generally have a minor function and does not cause further problems for the patient. The most commonly used grafts are the bone-patellar graft, tendon-bone graft and the hamstring tendon grafts which involve borrowing tendons from different parts from the knee. The torn ACL is first excised and bony tunnels are created in the upper tibia and lower femur which are the bones which constitute the knee joint and at places where the native ACL was attached. The tendon graft is then passed through these tunnels and secured at either end with suitable implants.
Meniscal injuries are commonly referred to as "torn cartilage". The meniscus is a C-shaped cartilaginous structure within the knee joint in between the joint surfaces of the knee. There are two types of meniscus in each knee and they are tough and rubbery. It acts like a shock absorber and is one of the commonly injured structures in the knee. This injury can occur in any age group and is usually a result of twisting of the knee in younger individuals. The meniscus becomes weaker with age and can occur in older individuals with minor injuries.
Meniscal tears are generally of different types and a bucket-handle type of tear usually gives the most trouble. These can cause the torn part to come into the joint and get wedged between the 2 joint surfaces (of the shin and thigh bone) causing the joint to get 'locked'. Here there is tremendous pain and inability to fully extend the knee. It has been described as getting something wedged in the hinges of a door causing the door to get stuck.
• X-rays are not useful however may help in diagnosing other follow-up damage or injuries
• MRI scans can detect meniscal tears and can also delineate the type of tear and thereby help in the treatment
Peripheral tears have some capacity to heal; unfortunately, tears in the periphery of the meniscus are uncommon. Most meniscal tears do not heal and require surgery in the form of arthroscopy.
Arthroscopic surgery may be in the form of excision of the torn fragment (meniscectomy) or repair (if the tear is in the periphery). Meniscal repair is usually performed in young individuals when the tear is in the periphery.
Following meniscectomy, there is usually no restriction in weight-bearing, although patients may need support with crutches. After meniscal repair, patients will be asked to remain non-weight bearing with crutches for a few weeks followed by gradual exercises to regain movement in the knee and weight bearing. Results are generally good and there is considerable decrease in pain.
Loose bodies are fragments made up of cartilage, bone or a mixture of both which get detached and usually move within the joint. They are usually a result of an injury or even a joint disorder; termed as Osteochondritis Dissecans or OCD (OCD is a condition when a small segment of bone begins to separate from its surrounding region due to a lack of blood supply.). The size of the fragment can vary from very small to large ones. The larger fragments are generally the ones which cause symptoms such as locking or catching of the joint when they get wedged between the joint surfaces. This can also lead to considerable pain and can cause the joint to fill up with fluids and swell.
• Fragments containing bone can be diagnosed on a simple x-ray
• Damage to cartilage are better visualised on an MRI scan
Treatment depends on several factors and is usually by arthroscopy (key-hole procedure). Smaller fragments are excised. Larger fragments can also be excised unless they arise from important weight bearing areas of the joint surface. Surgeons may decide to try and reposition the fragment back to its origin and secure it using pins or screws which may be metallic or bio absorbable depending on the surgeons' choice.
If the fragment has been excised, then post operation, weight bearing as normal is allowed. However, if the fragment is repaired, then patients will be provided with crutches to take the pressure off the affected knee. Knee movement is gradually commenced up to a certain limit to prevent pressure on the repaired cartilage. This will be determined by the surgeon based on the location of the repaired cartilage.
Results from this procedure are satisfactory, however, failures are known to occur and the fragment may require excision if it fails to heal and detaches again.
CARTILAGE INJURIES AND AUTOLOGOUS CHONDROCYTE IMPLANTATION (ACI)
Articular Cartilage Lesions causes roughening of the joint surface and can cause arthritis of the joint. Sometimes, the lesion can be deep enough exposing the bony surface. This can cause severe pain on weight bearing.
Articular Cartilage Lesions are classified from Grade 1 to 4 depending on the severity of the lesion. A grade 4 lesion is a full thickness lesion with bone exposed. Minor lesions may not cause any symptoms.
These lesions can occur due to injury, but more commonly are a result of wear and tear within the knee.
• Diagnosis is generally done by MRI scans.
• Severe, long standing lesions which have caused progression to arthritis can be visualised on an x-ray.
There are different types of treatment which can be offered, mostly by arthroscopic surgery (Key-hole procedure). Long-term studies are still awaited for cartilage regeneration surgeries, however short term studies have been shown to be promising.
Some of the procedures which have been described are:
• Arthroscopic debridement- Here the loose bits of cartilage are excised by arthroscopic surgery. This is mainly to clean up the joint and generally has only a short term effect.
• Microfracture technique- This is usually performed in lesions where the underlying bone is exposed and the lesion fairly large. An awl is used to make small holes in the bone in multiple sites. This is done to incite a healing response and blood vessels start growing towards the surface and produce fibro cartilage (scar tissue) to cover the defect and hence help in pain relief.
• Autologous chondrocyte implantation (ACI) - This is recently developed method for cartilage regeneration which is usually recommended for younger individuals. Results have been shown to be better in smaller, well localised lesions. It is usually a staged procedure and consists of 2 procedures with a gap of about 6 weeks. The first surgery is to harvest healthy cartilage from non-weight bearing portion of the knee. These cells are then grown in a lab to a larger volume.
Rehabilitation after surgery usually involves a continuous passive motion device to mobilise the knee. This helps to avoid joint stiffness. The limit to which patients will be allowed to move the joint depends on the site at which the cartilage has been repaired. Emphasis is to avoid putting strain on the repair site. Once reasonable movement has been achieved, strengthening exercises are started. Weight bearing status will again be determined by the surgeon depending on the position of the repair site.
TOTAL KNEE REPLACEMENT
Knee replacement surgery - clinically better known as arthroplasty entails the procedure of surgically removing diseased cartilage and bone particles from the knee area, knee cap, thigh bone and the shin bone, replacing them with artificial joints and peripherals made of metal alloys, high grade plastics and polymers
If the knee is severely damaged either by arthritis or due to a serious injury, performing even the simplest of tasks may turn out to be the extremely painful. Even walking may be a problem and if all non surgical treatments like medications and/or the use of walkers and other devices are no longer functional, considering an arthroplasty or knee replacement surgery would be the most permanent solution.
Knee joint replacement surgery is completely safe and the most effective and permanent procedure in case the knee is damaged beyond recovery.
The first knee replacement surgery was performed in 1968. Since then, there have been certain definite improvements in implant materials, design and techniques which in turn have thoroughly enhanced the effectiveness of the total knee replacement procedure. Today total knee replacements are one of the most successful procedures performed.
There are certain specific conditions in which doctors may recommend the total knee replacement procedure; the most common of them being the knee that has 'bowed' or bent inwards as a result of severe arthritis. However, one who has a regular stiffness that limits the random use of the knee joints and legs or anyone who is suffering at large due to a continuous severe knee pain regardless of any physical activity, can also be recommended for a total knee replacement surgery.