Adult Reconstruction Service

The Adult Reconstruction Service provides diagnosis, treatment, and rehabilitation for individuals with degenerative and inflammatory bone disease, bone injuries or deformities. Our orthopaedic surgeons are highly trained, experienced and are knowledgeable in the latest research, surgical techniques and implant technology.

Conditions treated include:

• Avascular necrosis

• Cartilage injury

• Degenerative joint disease (osteoarthritis)

• Failed joint replacement

• Femoroacetabular impingement

• Hip fracture

• Labral tear

• Meniscus tear

• Pathologic fracture

• Peri-prosthetic fracture

• Peri-prosthetic infection

• Post-traumatic arthritis

• Rheumatoid arthritis

Some of these conditions are explained in greater detail below:

Osteoarthritis is the most common form of arthritis, affecting millions of people worldwide. It occurs when the protective cartilage on the ends of your bones wears down over time. Although osteoarthritis can damage any joint in your body, the disorder most commonly affects joints in your hands, knees, hips and spine.

Osteoarthritis (OA) means inflammation of the joints although it is better known as a degenerative disease due to the inflammation of the joints although it is better known as a degenerative disease due to the inflammation of the joints with thinning of the articular cartilage. The cartilage in our joints allows for the smooth movement of joints. When it becomes damaged due to injury, infection or gradual effects of ageing, joints movement is hindered. As a result, the tissues within the joint become irritated, causing pain and swelling within the joint.

Rheumatoid arthritis (RA) is a systemic, inflammatory disease in which joint disease is center- stage, with a background of various manifestations. Systemic means that many parts of the body can be involved. Inflammatory means that the patient presents with redness, warmth, swelling, and functional limitation in the joints. This can lead to joint damage.

This form of arthritis usually involves many joints throughout the body at the same time and is caused by a problem with the immune system attacking your own joints, resulting in joint inflammation. Arthritis caused by inflammation often results in pain and stiffness after periods of rest or inactivity, particularly in the morning. The swelling, redness, and warmth may be present in the affected joints, but other areas in the body can be affected by the inflammation as well, such as the eyes and the lining around the heart.

Post-traumatic arthritis is caused by the wearing out of a joint that has had any kind of physical injury. The injury could be from sports, a vehicle accident, a fall, a military injury, or any other source of physical trauma. Such injuries can damage the cartilage and/or the bone, changing the mechanics of the joint and making it wear out more quickly. The wearing-out process is accelerated by continued injury and excess body weight.

Avascular necrosis (AVN), also called osteonecrosis, aseptic necrosis, or ischemic bone necrosis, is a    condition that occurs when there is loss of blood to the bone. Because bone is living tissue that requires blood, an interruption to the blood supply causes bone to die. If not stopped, this process eventually causes the bone to collapse.

Avascular necrosis most commonly occurs in the hip. Other common sites are the shoulder, knees, shoulder and ankles.

In order to correct this problem, surgical techniques employed by our surgeons include osteotomy, total joint replacement surgery, core decompression and vascularized fibula graft etc.

Two of these procedures are explained in greater detail below:

This procedure involves drilling one larger hole or several smaller holes into the femoral head to relieve pressure in the bone and create channels for new blood vessels to nourish the affected areas of the hip. When osteonecrosis of the hip is diagnosed early, core decompression is often successful in preventing collapse of the femoral head and the development of arthritis. Core decompression is often combined with bone grafting to help regenerate healthy bone and support cartilage at the hip joint. A bone graft is healthy bone tissue that is transplanted to an area of the body where it is needed. Many bone graft options are available today. The standard technique is to take extra bone from one part of your body (harvest) and move (graft) it to another part of your body. This type of graft is called an autograft.

In this procedure, a segment of bone is taken from the small bone in your leg (fibula) along with its blood supply (an artery and vein). This graft is transplanted into a hole created in the femoral neck and head, and the artery and vein are reattached to help heal the area of osteonecrosis. The patient's own tissue to rebuild diseased or damaged hip joints. He or she then removes the bone with the poor blood supply from the hip and then replaces it with the blood-vessel-rich bone from another site, such as the fibula, which is the smaller bone located in the lower leg.

Common surgical procedures performed by our surgeons include the following:

Arthrodesis refers to the fusion of two or more bones in a joint. In this process, the diseased cartilage is removed, the bone ends are cut off, and the two bone ends are fused into one solid bone with metal internal fixation. There is no further motion in the joint, but it is stabilized and, most importantly, pain caused by instability is eliminated.

In joint replacement surgery (arthroplasty), your surgeon removes your damaged joint surfaces and replaces them with plastic and metal parts.  Artificial joints can wear out or come loose and may need to eventually be replaced.

Arthroscopy is a surgical procedure the surgeons uses to visualize, diagnose and treat problems inside a joint. In an arthroscopic examination, the surgeon makes a small incision in the patient's skin and then inserts pencil-sized instruments that contain a small lens and lighting system to magnify and illuminate the structures inside the joint. Light is transmitted through fiber optics to the end of the arthroscope that is inserted into the joint.

By attaching the arthroscope to a miniature television camera, the surgeon is able to see the interior of the joint through this very small incision rather than a large incision needed for surgery. 

The television camera attached to the arthroscope displays the image of the joint on a television screen, allowing the surgeon to look, for example, throughout the knee. This lets the surgeon see the cartilage, ligaments, and under the kneecap. The surgeon can determine the amount or type of injury and then repair or correct the problem, if it is necessary. 

If osteoarthritis has damaged one side of your knee more than the other, an osteotomy might be helpful. In a knee osteotomy, a surgeon cuts across the bone either above or below the knee, and then removes or adds a wedge of bone. This shifts your body weight away from the worn-out part of your knee.

Like total hip, total knee replacement is considered the “gold standard” approach for the treatment of extensive knee arthritis. In total knee replacement, the damaged areas of the knee are exposed and removed; the remaining bone is prepared to receive the artificial knee joint, and then the prosthesis is inserted. Where appropriate, we use minimally invasive techniques that allow for smaller incisions.

At SGH, TKR surgeries boast a very high patient satisfaction rate of 93%. With modern day implants, we expect most of our total knee arthroplasties to have a longevity of more than 15 to 20 years. 

Total knee replacement (TKR) is able to alleviate pain and relieve dependence on analgesia, improve walking and stair-climbing performance and correct gross deformity resulting from the disease. The outcomes of TKR surgery are excellent overall both in terms of satisfaction rate, with 80 to 90% of patients being content with their surgical outcome and longevity, with over 90% of implants surviving beyond 10 years.

In partial knee replacement, only one section – or “compartment” – of the knee is replaced, instead of the entire joint. Partial knee replacement may be appropriate for some patients in which the arthritis is confined to a single compartment. Your surgeon will determine whether you may be an appropriate candidate.

A number of studies of knee and hip replacements have shown that after 20 years, 90 percent or greater are still functioning, and after 30 years the rate is about 70 percent. This means that 20 years following the surgery, nine out of ten patients will have a functioning implant and will not need another surgery, and 30 years following surgery, seven out of ten patients will still have a functioning hip implant.

We also provide robotic and computer-assisted surgery for hip and knee replacement procedures. More information can be found below.

As the only active robotic surgical system cleared by the FDA for orthopaedic surgical procedures, the ROBODOC® brings an unparalleled level of precision to Total Joint Replacement. It has been used in more than 24,000 successful procedures worldwide.

ROBODOC® is able to perform the surgery more precisely than the usual manual technique, and this is a tremendous asset for the patient. During the actual surgery using ROBODOC®, the robot precisely mills the bone surfaces, ensuring the exact fit and position of the implant based on the pre-operative plan. ROBODOC® assists the surgeon in assuring that the final bone preparation matches the pre-operative plan exactly.

With the ROBODOC® total joint replacement procedure, the surgeon maintains complete control of the robot as it executes the patient specific plan. The surgical results provided by ROBODOC® are exactly what have been planned. That’s because the ROBODOC® Surgical System provides consistent reproducible precision in every procedure due to its unique active robotic technology. Robotic surgery reduces intra-operative and post-operative fractures and provides good alignment to the bone. 

Clinical studies have demonstrated that ROBODOC® milled bone cavities and joint surfaces provide for better implant fit, fill and alignment compared to conventional manual surgery. ROBODOC’s specialized drill bits and other hardware have been developed for accurately preparing the bone to achieve optimal fit of the prosthetic implant. The robot mills cavities for hip implants, removes bone cement for revision surgeries, and planes the femoral and tibia surfaces for knee implants. 

Benefits of the ROBODOC® System over traditional methods include improved cavity fit, fill and alignment for prosthetic implants as well as a reduction of leg length discrepancy, intra-operative fractures and pulmonary emboli. The robot cuts bone to an accuracy of 0.02mm - finer than a strand of hair. Such precision is unmatched by other techniques, no matter how good the doctor is. Generally, in total knee replacement surgery (which the robot is programmed for), the maximum error allowed is a mere 3 degrees. Robotic-assisted TKR aims to take this one step further by having the cutting process to be fully performed by a cutting robot. 

The planning for robotic surgery employs similar principles as computer navigated total knee arthroplasty. The difference is that the planning is performed from preoperatively acquired Computed Tomography (CT) scanning of the patient’s lower limb. With this, the centre of the hip, knee centre and the centre of the ankle can be precisely calculated and the surgery planned pre-operatively. The surgery plan is then uploaded into the ROBODOC® Surgical System, which executes the actual cutting of the bone during surgery.

During the surgery, the cutting of the bone is entirely performed by the ROBODOC® Surgical System which utilises a milling procedure. This procedure is highly precise – up to submillimetre precision. An added advantage of the ROBODOC® surgery is that the sharp robotic cutting mill would not go anywhere close to critical soft tissues surround the joint, namely the major neurovascular bundles that lurk in the posterior part of the knee, and the collateral knee ligaments during the surgery.

MAKOplasty is a surgical procedure for total knee, partial knee or total hip arthroplasty using a RIO Robotic Arm Interactive Orthopedic System developed by MAKO Surgical Corp. RIO is cleared by the FDA for use in surgical knee and hip procedures, in which the use of stereotactic surgery may be appropriate, and where reference to rigid anatomical bony structures can be identified relative to a CT-based model of anatomy.

With MAKOplasty, surgeons are able to plan these procedures by using three-dimensional computer imaging based on a CT scan. This allows them to determine optimal implant size, position and alignment for each individual patient, as well as map out accurately the areas of bone they want to remove. 

During surgery, the robotic arm system provides visual, auditory, and tactile control to help assure that surgeons cut away only the bone planned to be resected prior to surgery. The procedure is said to take the guesswork out of surgery, resulting in accurate and reproducible results.

 

The Mako Robotic-Arm Assisted Technology with Triathlon Total Knee implants is an example of how technology is transforming the way joint replacement surgeries are being performed. An orthopaedic surgeon uses the Mako System software to pre-plan a patient’s surgery. The orthopaedic surgeon will guide the Mako robotic-arm to remove diseased bone and cartilage. Then the surgeon will insert a Triathlon Total Knee implant. Mako Technology was designed to help surgeons provide patients with a personalized surgical experience based on their specific diagnosis and anatomy.

With over a decade of clinical history, Triathlon single-radius knees are different than traditional knee replacements because they are designed to work with the body to promote natural-like circular motion. This is due to the single radius design of the knee implant. Single radius means that as your knee flexes, the radius is the same, similar to a circle, potentially requiring less effort from your quadriceps muscle. The quadriceps muscle plays an important role in one’s ability to move their legs so it also has a major impact on a patient’s recovery and how quickly he or she is able to get back to living their life.

For partial-knee replacements, MAKOplasty allows surgeons to remove only the diseased portions of the joint, preserving healthy tissue and ligaments, resulting in a more natural feeling knee. The procedure can be performed on the medial compartment, the lateral compartment, the patello-femoral compartment or on a combination of the medial and the patello-femoral compartments of the knee. This procedure is designed to relieve the pain caused by joint degeneration due to osteoarthritis (OA) in one or two compartments of the knee. By selectively targeting the part of the patient’s knee damaged by OA, the surgeon can replace the diseased part of the knee while helping to spare the healthy bone and ligaments surrounding it.

The MAKOplasty technology provides the surgeon with a patient-specific 3-D model to pre-plan the partial knee replacement procedure. During surgery, the surgeon guides the Mako robotic-arm based on the patient-specific plan. This allows the surgeon to remove only the diseased bone, preserving healthy bone and soft tissue, and assists them in positioning the implant based on the patient’s anatomy.

The same study also concluded that MAKOplasty unicompartmental knee arthroplasty is more accurate than manual unicompartmental knee arthroplasty. A different study reported that MAKOplasty is two-to-three times more accurate than manual techniques for partial knee implant placement.

Using MAKOplasty for PKR is 3 times more accurate than manual surgery and requires only minimal invasion. This means lesser tissue damage and lesser pain after surgery. The optimal position of a patient's custom implant also means that his or her knee feels very natural. Thus, the patient will feel safe as the procedure is so precise.

According to a randomized controlled trial, MAKOplasty patients experience less pain during the first week after surgery than do patients who underwent manual surgery after two months. This can potentially result in a more rapid recovery and shorter hospital stay than traditional total knee replacement surgery.

MAKOplasty® Hip is an innovative total hip replacement (arthroplasty) procedure that is performed using a highly advanced, surgeon-controlled robotic arm system. It can be a treatment option for people suffering with either non-inflammatory or inflammatory degenerative joint disease, and is designed to assist surgeons in attaining a new level of reproducible surgical precision in hip surgery.

The goal of using robotic arm technology to perform hip replacement is to attain consistent precision in surgery. Accurate placement and alignment of implant components are a critical factor in hip replacement.

The use of robotics helps the surgeon place the implants in the desired location with incredible accuracy, providing an excellent, stable biomechanical reconstruction and unprecedented leg length restoration. It is performed with the RIO® Robotic Arm Interactive Orthopedic System. RIO enables the surgeon to use a 3-D anatomic reconstruction based on a CT scan of the patient’s own hip to pre-surgically plan implant positioning. During the procedure, it provides real-time data for intra-operative adjustments to further enable me to optimally align and position implants, and accurately reproduce the surgical plan.

Our surgeons perform all robotic hip replacements via a muscle-sparing approach, i.e. no muscles are cut in exposure or preparation of the hip joint. The robot ensures that the surgeon is able to both plan and place the components with enhanced accuracy and precision, while providing real time information in surgery. This allows adjustments, even minute, to be made prior to the culmination of the procedure, thus reducing the risk of subsequent complications/reoperations.

Other than shorter hospital stays and a more rapid recovery, patients who have undergone a MAKOplasty procedure reported having a more natural feeling knee. The procedure also significantly reduced scarring for these patients.

The NAVIO Surgical System encompasses the following features:

• Real-time imaging

With its real-time imaging feature, the surgical process for patients is simplified. More focus will be on patient care as office staff need not spend time managing payer approvals for preoperative imaging.

• Handheld robotics

Surgeons are able to use the NAVIO hand piece to execute bone resection procedures within his or her defined plan, which is also patient specific.

• Patient-specific surgical plans

It encompasses a feature-rich intraoperative planning software. With the use of this advanced technology, surgeons will be able to create a highly individualized plan that is specific to the unique shape and motion of a patient's knee.

• Multiple implant options

The NAVIO◊ Surgical System is designed for use in both partial and total knee replacement procedures.

• CT-free technology

A virtual representation of each patient’s anatomy is recreated through direct anatomic mapping kinematic registration. This robotics-assisted platform uses CT-free technology for precise implant sizing and positioning without the need for rods. The patient is not exposed to the potentially harmful radiation experienced through CT scans. 

A more in-depth explanation of both the partial and total knee replacement procedures are stated below:

o Partial Knee Replacement

In partial knee replacement, a patient's supporting tissue and ligaments that help stabilize their knee are spared and only the damaged portion of the knee is replaced. This means that healthy cartilage and bone remain intact to help a patient's knee joint move smoothly with the prosthetic implant. Patients with osteoarthritis in only one area of their knee may be candidates for partial knee replacement. Patients who undergo partial knee replacement often report a 'more normal' feeling knee, less pain and quicker rehabilitation. Using the NAVIO system, the surgeon creates a 3D representation of the unique shapes and profiles of a patient's knee without the need of a pre-operative CT scan. Using all of this information, he or she can then determine the correct size and position of the implant. Implant size and position is critical to knee alignment and stability. Next, the surgeon uses robotic assistance of NAVIO to physically remove only the damaged bone, preparing the site for the prosthesis, before placing and adjusting the partial knee implant.

o Total Knee Replacement

In total knee replacement, the entire knee joint is replaced with a prosthetic implant designed to replicate the shape, motion and stability of a patient's natural knee joint. Total knee replacement is one of the most common procedures performed in all of medicine. Ninety percent of people who receive a total knee replacement experience a dramatic decrease in knee pain and an improvement in their ability to perform daily activities. With the NAVIO system, the surgeon creates a 3D representation of the unique anatomy of a patient's knee without the need of a pre-operative CT scan. He or she then use this knee anatomy information to determine the correct size and position of the implant and create a surgery plan unique to a patient's anatomy.

The treatment of end-stage knee osteoarthritis with total knee replacement has always been a significant part of the workload of orthopaedic surgeons in SGH. In our department, TKR surgeries boast a very high patient satisfaction rate of 93%. With modern day implants, we expect most of our total knee arthroplasties to have a longevity of more than 15 to 20 years. In spite of this, we are constantly striving to improve the outcome of this important surgery by bringing in the best and latest technologies to further improve the outcome of this surgery. 

The surgical aim of the total knee arthroplasty is to ensure that the knee prostheses are placed in the correct positions. This is largely dependent on the accuracy of the bone cuts. Suboptimal placement of the prostheses will lead to knee malalignment, suboptimal knee range of motion, knee strength and increased occurrences of post-operative knee pain. Malpositioning also negatively impacts on the longevity of the knee replacements. 

Total knee arthroplasty using conventional cutting instrumentation has been the time-tested workhorse technique that is familiar to most orthopaedic surgeons. 

In this technique, surgeons rely on anatomical landmarks such as the femoral bow, tibial crest, medial and lateral malleolus to calculate the angles of the cuts necessary for the patients. The development of various computer-assisted techniques helps to improve on the accuracy of implant placements further.

Computer navigated total knee arthroplasty was introduced into the SGH Department of Orthopaedic Surgery around 2004. For this technique, the surgeon relies on several additional instruments to allow a computer to monitor the positions of the tibia and femur bones in a three-dimensional space during the surgery.

These instruments are:

• A tracking system

It is a pair of binocular sensors that are placed about 1-2 metres away from the patient. 

• Rigid markers

The rigid markers tell the Tracking system the positions of the various structures being tracked. These markers can be divided into the bone and instrument markers. The first two markers are attached to the femur and tibia bones to allow the Tracking system to be aware of the positions of the bones in a three-dimensional space.

The bone markers need to be implanted into the bone through small stab wounds, which are often cosmetically insignificant eventually. The instrument markers are attached to a sawing jig to enable the Tracking system to be aware of the position of the eventual bone cuts with respect to the bones.

• Computer platform

The computer platform receives the inputs from the rigid markers and mathematically computes the three-dimensional position of the bones and the cutting instruments. More advanced systems also plan the surgery and help guide the surgeon to the exact amount of bone cut so as to achieve good postoperative ranges of motion.

The surgical exposure for computer assisted total knee arthroplasty is similar to that of conventional techniques. However, we are able to achieve a smaller incision due to the assistance from the computer navigation. The additional stab incisions for the implantation of the trackers are often cosmetically insignificant after a period of scar maturation.

During surgery, the surgeon would need to use the hand-held markers to perform an anatomy survey to enable the Computer platform to compute the shapes of the tibia and femur so that it can calculate the centre of the knee joint, hip joint and the ankle joint. The beauty of this system is that this calculation can be calculated with great precision, regardless of any inherent malformation of the tibia and femur. 

A second advantage is that it completely obviates the need for the surgeons to insert a long rod into the medullary canal of the femur in the conventional technique. This will lead to lower blood loss for the patient. It can also work when there are pre-existing implants in the femur, such as intramedullary nails and proximal femur nails in patients with previous antecedent femoral fractures.

Surgeons do not need to remove these implants to perform the total knee replacement, thereby saving the patients from additional surgery to remove the otherwise obstructing implants. After the cutting positions are determined by the computer navigation system, the surgeon then manually cuts the bone with the conventional saw.

A recent article published in the prestigious Journal of Bone and Joint Surgery shows that in patients younger than 65 years old, computer navigation-assisted TKRs can lead to longer lifespan of the prosthesis. This is great news for these patients as the chances of them coming back for a revision surgery would be lowered.

  

The results of computer navigation surgery are excellent. Numerous studies worldwide have shown that implant placement for TKR using computer navigated techniques is much more precise than using conventional instrumentation. This in turn translates into better patient outcomes. After recovering from the surgery itself and following a period of physiotherapy and exercise, patients report being able to bend their knee to a much greater angle than those who have had standard total knee joint replacement.