1. What is the knee?
The knee joint is the articulation formed by the lower end of the femur (thigh bone), upper end of the tibia (leg bone) and the patella. It is the largest and one of the most easily injured joints in the human body. Its function is intricately involved in stance and ambulation. The patella slides in a narrow groove at the lower end of the femur; the articulating surfaces of the 3 bones are lined with articular cartilage to facilitate pain-free motion. The other associated structures are the tendons, meniscus and ligaments.
|
2. What procedures do I need to undergo to diagnose my knee problem?
Establishing the diagnosis of your knee problem starts with a complete history and physical examination. Patients suspected of having meniscal tears or ligamentous injuries are advised to undergo an MRI of their injured knee. A series of x-ray views are requested for patients in whom knee osteoarthritis is considered.
|
3. What is the meniscus?
They are 2 wedge-shaped tissues (medial & lateral meniscus) made up of a specialized form of cartilage located on the upper end of the tibia. The meniscus aids in painless weight bearing, decrease joint contact pressure and contributes to joint stability.
|
4. What are meniscal tears?
Meniscal tears are disruptions in the continuity of the meniscus. Twisting of the knee while in a standing position is the usual mechanism that produces these tears. Symptoms experienced by the patient ranges from pain, swelling, catching and locking depending on the severity of the tear. These injuries may be either traumatic or degenerative; traumatic tears are common from late adolescence up to the late forties while degenerative tears are seen in the older population (no history of trauma). Neglected meniscal tears could contribute to early onset osteoarthritis due to repetitive erosion of the articular cartilage from loose, irregular or trapped meniscal fragments.
Treatment:
Patients who have small tears have minimal symptoms and they do not usually require treatment. Those who have large tears or persistent symptoms need to undergo arthroscopic surgical excision (menisectomy) or arthroscopic repair of the torn meniscal fragment. The goal of menisectomy is to preserve as much meniscus as possible by minimizing the removal of the unstable and irreparable meniscal fragments only. Majority of meniscal tears are non-repairable (90%); repairable tears are tears in the outer margin of the meniscus and best results are achieved when repair is performed within 6-8 weeks from the time of injury.
|
5. What are the knee ligaments
Ligaments are tissues that confer stability in joints; they are responsible for restricting abnormal or excessive motion in joints. There are 4 main ligaments in the knee joint namely: the Anterior & Posterior Cruciate Ligaments and Medial & Lateral Collateral Ligaments. The Anterior Cruciate Ligament (ACL) & Posterior Cruciate Ligament (PCL) have a central location inside the joint (intraarticular) while the Medial Collateral Ligament (MCL) & Lateral Collateral Ligament (LCL) are located on the inner and outer sides of the knee joint (extra-articular). The healing potential of the intraarticular and extra-articular knee ligaments is different, the intraarticular ligaments (ACL & PCL) are not known to heal when they are torn while the extra-articular ligaments (MCL & LCL) usually heal spontaneously.
Anterior Cruciate Ligament (ACL)
The ACL is the structure that prevents the forward displacement of the leg bone (tibia), it also contributes to the rotational stability of the knee. The ACL can be injured in a number of ways such as: 1) twisting injury 2) sudden stop while running or sudden change of direction 3) violent landing after a jump 4) direct trauma. The ACL may sustain a sprain (mild stretching) or could be completely torn; the symptoms of a torn ACL are similar to an intact but fully stretched-out ACL. A patient who suffered an ACL tear may hear a “popping sound” during the accident and they could feel that their knees are giving out (buckle); patients may also develop meniscal tears during the time of their injury. The patients will develop pain, knee swelling and difficulty of ambulation a couple of hours after their accident. Knee experts believe that damaged ACLs should be reconstructed because patients with an injured ACL develop instability and are at risk of damaging their articular cartilage.
Treatment:
The initial management of ACL tears is nonsurgical; the patient is advised to initiate range of motion exercises and hamstring strengthening after the initial symptoms of pain and instability has subsided. Patients who desire to return to their previous level of athletic activity are advised to undergo ACL Reconstruction because ACL tear doesn’t heal. The procedure is performed arthroscopically and the ACL is reconstructed with the hamstring tendons or part of your patellar bone and patellar tendon; any concomitant meniscal tears are dealt with during the surgery.
Click here to view an animation of an Arthroscopic ACL Reconstruction - Hamstring Graft
Click here to view an animation of an Arthroscopic ACL
Reconstruction - B-PT-B Graft
Posterior Cruciate Ligament (PCL)
The PCL is the strongest knee ligament; its primary role is to prevent the backward displacement of the leg bone. Isolated PCL tears are less common than ACL tears and combined tears of the ACL and PCL could be seen in patients with severe knee injuries. The mechanism of injury is usually a direct blow to the knee or a misstep that leads to knee hyperextension. Patients may also hear a pop during their accident; they will also develop knee swelling and instability that is lesser than the one observed in patients with ACL tears.
Treatment:
Isolated tears of the PCL are initially treated nonsurgically which consists of flexibility and quadriceps strengthening exercises. Patients with persistent or recurrent instability are advised to undergo an arthroscopic PCL Reconstruction.
Medial Collateral Ligament (MCL)
The MCL is the ligament on the inner side of the knee; it is responsible for resisting the outward displacement (valgus) of the leg bone. The MCL is injured when an inward directed force is exerted on the knee joint (like in a football tackle). Patients with MCL tears present with pain and swelling on the inner part of their knee. The MCL may be sprained or completely torn and it can occur alongside patients with meniscal and ACL tears.
Treatment:
The treatment of MCL tears is nonsurgical which consists of pain medications and a knee brace worn for at least 4 to 6 weeks.
Lateral Collateral Ligament (LCL)
The LCL is the ligament on the outer side of the knee; it is responsible for resisting the inward displacement (varus) of the leg bone. The LCL may be injured when an outward directed force is exerted on the knee joint. Patients with LCL tears present with pain and swelling on the outer part of their knee. The LCL may be sprained alone or occur with capsular, meniscal and cruciate ligament tears when it is completely torn.
Treatment:
The initial management of LCL tears is similar to MCL tears; consisting of pain medications and a knee brace worn for at least 4 to 6 weeks. The patient is gradually allowed to go back to their daily and sports activities and is advised to observe their knee for persistent pain or instability. Patients with persistent instability symptoms may need to undergo reconstruction of their Posterolateral Ligament Complex (PLC).
|
6. What is Double-Bundle ACL Reconstruction?
This is a specialized type of ACL Reconstruction which aims to restore the anatomy of the anterior cruciate ligament which consists of two bundles, the anteromedial and posterolateral. Reconstructing the ligament in this manner is said to better afford rotational stability to the knee. Rehabilitation is different for that of the conventional ACL Reconstruction.
‹
|
7. What is Knee Osteoarthritis?
Knee Osteoarthritis is a degenerative condition whose hallmark is the loss of articular cartilage and joint incongruity. The loss of articular cartilage results in stiffness and painful bone-to-bone contact whenever the individual walks or stands up; symptoms are usually worse in the morning and characteristically improve in the afternoon after the knee sufficiently “warms up”. This condition may be primary but it may also be secondary to other predisposing conditions. Most patients with knee osteoarthritis would only require simple knee x-rays. The characteristic findings in knee osteoarthritis are narrowing of the joint space and osteophytes (spur) formation.
Treatment:
The initial management of osteoarthritis is non-surgical; it includes weight reduction, activity modification, low impact and strengthening exercises. Pain medications, steroid injections, viscosupplement injections and use of walking canes may be helpful during severe pain episodes. The surgical treatment of knee osteoarthritis is based on the age and functional demands of the patient. The surgical options are knee arthrodesis, osteotomy and knee replacement. Arthrodesis involves the surgical connection of the leg and thigh bone; this procedure eliminates pain but at the expense of losing knee mobility. Osteotomy (bone cutting) procedures are bone realignment procedures that intends to normalize weight distribution and contact forces in the knee; this procedure is reserved for patients with minor deformities or misalignment and concomitant unicompartment symptomatic osteoarthritis.
|
8. What is Total Knee Replacement (TKR)?
Total Knee Replacement is a surgical treatment available for patients with severe knee osteoarthritis. The surgery involves the removal of the remaining irregular articular cartilage in the articulating surfaces of the femur, tibia and patella; the excised cartilage are then replaced with a new bearing system composed of a metal alloy (on the femur) and a special form of thermoplastic liner (on the tibia and patella). The goal of the surgery is to provide a pain-free joint and to restore normal alignment of the knee. A young or middle-aged active adult who underwent a Total Knee Replacement will require future revision surgery so it is best to delay TKR as long as possible.
|
9. What is MIS-Quadriceps Sparing Total Knee Replacement?
Quadriceps Sparing Total Knee Replacement is a form of Minimally-Invasive Surgery that entails a much smaller incision and avoids surgical trauma to the quadriceps. This operation, using the same implants thru specialized instruments, therefore allows active knee movement a few hours after surgery, and therefore allows patients to walk on the same day of surgery.
|
10. What are the advantages of MIS-Quadriceps Sparing Total Knee Replacement over traditional Total Knee Replacement?
Because of the avoidance of trauma to the quadriceps, the patient experiences much less pain and faster recovery and return to normal knee function. There is better patient satisfaction in general because of smaller scars, shorter hospital stay and shorter rehabilitation.
|
|
Incision
|
Tissue Trauma
|
|
MIS-Quadriceps Sparing TKR
|
3 to 5 inches
|
No Quadriceps tendon cut
|
|
MIS Mini-Incision TKR
|
4 to 6 inches
|
1 to 2 inch Quadriceps tendon cut
|
|
Conventional Total Knee Replacement
|
8 to 12 inches
|
Large Quadriceps tendon cut
|
|
11. What are steroid injections?
Steroids are a group drugs that have analgesic (pain-relieving) and anti-inflammatory (anti-swelling) effects. Patients who have severe pain episodes due to osteoarthritis that are unrelieved by oral pain medications may benefit from intraarticular steroid injections; steroids are injected with local anesthetics to attain immediate pain relief. Steroid injections should not be abused to avoid their potential side effect of tendon and ligament weakening (maximum of 3 injections in the same joint in one year) and it should be performed as cleanly as possible because of the risk for joint infection, which is catastrophic to the joint.
|
12. What can I expect during surgery?
You will be given antibiotics before you are brought to the operating theatre. Knee surgery is usually performed under Spinal Anesthesia (awake) but we could also perform the surgery under General Anesthesia (asleep) upon request. Patients undergoing Total Knee Replacement are usually given a pain catheter, either an epidural or a femoral nerve block to facilitate adequate pain relief after surgery.
|
13. What can I expect after my knee surgery?
If you underwent a
simple menisectomy, you will be immediately allowed to walk without much
restriction after your surgery but if underwent a meniscal repair, you
will be asked to use crutches for a few weeks to facilitate meniscal
healing.
Patients who underwent
an ACL Reconstruction are required to wear an ACL brace and undergo a
period of supervised rehabilitation. You should always ask the opinion
of your surgeon before any activity progression and returning to sports.
Patients who underwent Total Knee Replacement are asked to use crutches or a walker depending on their physical condition. A vacuum drain is usually placed in the operated knee for a couple of days to remove excess blood. If non-absorbable sutures were used to close your incision, they are usually removed 10-14 days after your surgery. Patients are also advised to undergo a period of supervised rehabilitation that will commence the day after surgery. If you underwent a MIS-Quadriceps Sparing TKR, you could generally expect to move your knee or even walk on the evening of your surgery day without weakness and pain.
|
