KNEE SURGERY
HIP SURGERY
ORTHOPAEDIC SURGERY
Meniscus Surgery
The knee joint is made up of the ends of the femur (thigh bone) and tibia (shin bone). The meniscus is a rubbery, C-shaped disc that cushions your knee. It also helps to protect the cartilage in the knee. Each knee has two menisci - one at the outer edge of the knee and one at the inner edge. ​The menisci function as shock absorbers in the knee and also help to maintain stability within the knee. Injuries to the meniscus can occur after acute traumatic injuries or chronic repetitive injuries. Meniscus injuries can result in pain, swelling and stiffness of the joint.
The diagnosis of a meniscus injury within the knee is made after a thorough clinical assessment of the knee. MRI scans are done to confirm the diagnosis and to look for concomitant knee injuries, such as ligament tears and cartilage injuries. ​Patients with small meniscus tears may be treated non-surgically with a course of rehabilitation. However, patients with large or displaced meniscal tears, who develop persistent pain, swelling and loss of joint function, are candidates for surgical treatment. ​Surgical treatment involves minimally invasive knee arthroscopy (or keyhole surgery) and includes the following options:
​
1. Meniscus repair (See Figures below): Given its important function within the knee, meniscus tears
should be repaired as far as possible. The meniscus is repaired by placing fine sutures within its
substance to keep it together while it heals.​​
​
2. Partial meniscectomy: Sometimes the meniscus tear is so severe that it precludes a repair. In this
instance, the torn non-functional part of the meniscus is removed using specialized instruments.
​
3. Meniscus transplant: In patients who develop pain in their knee because most or all of the
meniscus has been removed, meniscus tissue from a donor (allograft) may be transplanted into the
knee to replace the deficient meniscus.
​
At the same time, concomitant ligament and cartilage injuries may need to be addressed. Such surgery is usually performed under general anaesthesia and takes about 1-2 hours. An overnight stay in hospital is usually required after the surgery and 4-6 weeks of crutch-assisted ambulation may be advised.
​The rehabilitation process after the surgery is generally supervised by a physiotherapist, and consists of progressive knee range of motion exercises, muscle strengthening exercises, and sport-specific drills. The whole rehabilitation process may last to 4-6 months following the procedure. The success rate of meniscus surgery has been reported to be about 80-90%. The complications of this procedure include infection, meniscus retears and future osteoarthritis (if meniscectomy is performed).
Cartilage Repair
Joints are formed when the ends of two bones meet. For example, the knee joint is made up of the ends of the femur (thigh bone) and tibia (shin bone). Cartilage is the smooth elastic tissue that covers the ends of the bones at these joints. The cartilage allows for the joint surfaces to glide smoothly and painlessly against each other. Injuries to the cartilage can occur with acute traumatic injuries or with chronic repetitive injuries. Cartilage injuries can result in pain, swelling and stiffness of the joint. ​The diagnosis of a cartilage injury within the knee is made after a thorough clinical assessment of the knee. MRI scans are done to confirm the diagnosis and to look for concomitant knee injuries, such as meniscal tears and ligament injuries.
Patients with small cartilage injuries may be treated non-surgically with a course of rehabilitation. However, patients with cartilage injuries, who develop persistent pain, swelling and loss of joint function, are candidates for surgical treatment. ​Surgical treatment involves cartilage repair. Cartilage has a low potential for intrinsic repair because of its poor blood supply. Therefore specialized repair techniques are employed to repair this tissue. These include:
1. Bone marrow stimulation: Drilling or microfracture of the bone beneath the cartilage injury is
performed so as to allow stem cells from the bone marrow to form new repair cartilage at the
site of the cartilage injury.
​
2. Autologous matrix-induced chondrogenesis (AMIC) (See Figures below): In addition to drilling or
microfracture, a tissue scaffold is placed within the cartilage defect to enhance the cartilage
healing process.
​
3. Osteochondral autograft transfer (OAT): Fresh bone and cartilage from another part of the joint
is harvested and transferred to the site of cartilage injury so as to restore its structure.
​
4. Allograft transplantation: Bone and cartilage tissue from a donor can be used to reconstruct
large cartilage defects in the joint
At the same time, bone reshaping or osteotomy may also be performed to correct significant
abnormalities in joint alignment that may affect the cartilage healing process. Such surgery is usually
performed under general anaesthesia, using minimally invasive arthroscopic (keyhole) techniques. An overnight stay in hospital is usually required after the surgery and 4-6 weeks of crutch-assisted ambulation may be advised. The use of a continuous passive motion machine may also be beneficial.
​
The rehabilitation process after the surgery is generally supervised by a physiotherapist, and consists of progressive knee range of motion exercises, muscle strengthening exercises, and sport-specific drills. The whole rehabilitation process may last to 6-9 months following the procedure. The success rate of cartilage repair surgery has been reported to be about 70-90%. The complications of this procedure include knee stiffness, infection and cartilage reinjury.
ACL Reconstruction
ACL is an acronym for the ‘anterior cruciate ligament’. It is an important ligament that is found in the centre of the knee, and it helps to maintain knee stability by preventing forward and twisting movements of the tibia (or shin bone) relative to the femur (or thigh bone). Injuries to the ACL are common. They usually occur due to twisting, non-contact injuries during sporting activities such as soccer, basketball or netball.
​
The risk factors for ACL injuries include female gender and familial predisposition. The diagnosis of an ACL injury is made after a thorough clinical assessment of the knee. MRI scans are done to confirm the diagnosis and to look for concomitant knee injuries, such as meniscal tears and cartilage injuries.
​
Some patients with isolated tears of the ACL may be treated non-surgically with a course of rehabilitation. However, patients with symptoms of recurrent knee instability, those with concomitant repairable meniscal tears, and individuals who are keen to return to competitive pivoting sports (such as soccer, basketball or netball) are candidates for surgical treatment.
​​
Surgical treatment involves ACL reconstruction. This surgery is usually performed under general
anaesthesia, using minimally invasive arthroscopic (keyhole) techniques. The surgery essentially involves replacing the torn ACL with a new ACL graft. Bone tunnels are drilled in the femur and tibia within the knee, and a new ACL graft is secured within these tunnels. This new graft may be obtained from patient himself (autograft) or from a donor (allograft). At the same time, concomitant injuries to the menisci or cartilage may be repaired. An overnight stay in hospital is usually required after ACL reconstruction and 2-4 weeks of crutch-assisted ambulation may be advised.​
The rehabilitation process after the surgery is supervised by a physiotherapist, and consists of progressive knee range of motion exercises, muscle strengthening exercises, and sport-specific drills. The whole rehabilitation process may last 9-12 months following the ACL reconstruction procedure. The success rate of ACL reconstruction surgery has been reported to be about 90%. The complications of this procedure include ACL graft injury, knee stiffness and infection.
