Listed below is the step by step procedure of knee osteotomy:
- What is Knee Osteotomy?
- Why is Knee Osteotomy Required?
- Pre-operative Preparation
- Day Before Surgery
- Procedure Day
- Methods/Techniques of Knee Osteotomy
- Post Procedure
- Risks and Complications
What is Knee Osteotomy?
Osteotomy is a surgical procedure which involves altering the length or alignment of a bone to provide relief to the patient from any disorder of the joints formed by that particular bone.
Knee joint is formed by the femur (thigh bone) and two other bones, namely tibia and fibula. During knee osteotomy, a part of the upper section of tibia or lower part of femur corresponding to the damaged area of the joint are removed or a wedge of bone is added close to the damaged joint. This lifts excess pressure off the damaged knee joints.
Why is Knee Osteotomy Required?
Arthritis is the most common reason why osteotomy of knee joint may be done. However, every case of knee joint arthritis does not require this surgery. Indications of knee osteotomy are explained below:
Every surgery requires some pre-planning, and the same holds true for knee osteotomy. The patient needs to be explained about the procedure, they need to be examined, some investigations need to be done. Some of the pre-operative requisites are mentioned below:
- Discussion: Prior to the surgery, the orthopedic surgeon explains to the patient all about knee osteotomy. Its pre-surgical requisites, the procedure itself, its advantages and drawbacks are all discussed with the patient. A consent form duly filled and signed by the patient is required before the surgery.
- Investigations: Before surgery, certain blood tests are done to determine white blood cell count, blood sugar, kidney function and liver function. These tests have to be within normal limits. If not, they are normalized with appropriate medicine before the surgery. Blood group determination is done. Blood matching the patient's type is obtained from a blood bank prior to surgery. X-Ray of chest is done to visualize lungs and assess respiratory functions. ECG is done to check for any abnormality in heart functions.
- Evaluation of Knee Damage: Prior to knee osteotomy, the patient is examined thoroughly. The knee which is to be operated upon is examined in detail to assess its level of functioning. An X-Ray of the knee is done before the surgery. This will give the surgeon an idea about the extent of degeneration which has taken place within. Based on the examination findings and X-Ray report, the surgeon decides the course of surgery.
- Choosing the Graft: During osteotomy, a part of the bone corresponding to the damaged portion of knee joint is removed. A wedge is then inserted to replace the dissected bone. This wedge may be obtained either from another healthy bone belonging to the patient or from a human donor. The wedge may also be artificially synthesized. The surgeon chooses the type of graft and prepares it in advance before surgery.
- Knee Brace: Before surgery, the patient may be asked to wear a knee brace for a few days. This brace will align the knee joint in the same way as is planned to be done during knee osteotomy. Wearing the brace will help the patient and surgeon to judge the outcome of surgery and how it will benefit the patient.
- Pre-operative Physiotherapy: After surgery of knee joint, it is advisable to resume movements of the joint at a slow pace to avoid overburdening the joint. If the muscles around the joint are strong, there will be faster recovery from surgery and joint movements will be made easy. Therefore, physiotherapy is advised before surgery. Exercises, massage therapy, traction may be advised for muscle strengthening. Physiotherapy will be continued after surgery as well.
- Lifestyle Changes: Patients who consume alcohol or are smokers, will be instructed to abstain from smoking or drinking since a week or more before surgery. This restriction will be continued for some time after the surgery as well.
These preparations, save a lot of precious time during surgery. They also ensure that there is no obstacle which can hamper the successful outcome of the surgery.
Day Before Surgery
The day before surgery is filled with anticipation and anxiety for the patient. Patient will be advised to be admitted to the hospital a day before surgery. At times however, they may be asked to report to the hospital directly on the day of surgery.
A day before surgery, the patient will be examined thoroughly. If they have already been hospitalized, their blood pressure, pulse, breathing rate and body temperature (vitals) are monitored regularly.
Since the night before surgery, patient is instructed to abstain from consuming any food in solid or liquid form. Water can be consumed. But water intake is also restricted some hours prior to surgery.
Patient is prescribed antacids to control acidity. Sometimes, a laxative might be prescribed to clear the bowels before surgery. Patient is advised to preclude from physically strenuous activities.
If the patient has not been hospitalized a day before surgery, they are asked to report to the hospital well in advance before the time of surgery. A detailed physical examination is done up on the patient's arrival. The patient is asked to dress in a clean and sterilized surgical gown provided by the hospital. All clothing and equipment utilized for the surgery is subjected to sterilization, in order to get rid of microorganisms.
The skin through which surgical incision will be made is shaved and cleaned with an antiseptic solution. Before anesthesia is administered, the patient's vitals are checked again. They are continuously monitored throughout the surgery. General anesthesia is administered via an intravenous injection or via nasal route. Patient will become completely unconscious, in a few minutes after anesthetic agents have been administered. If regional anesthesia is used, then it can be administered into the spine. The sensation from waist downward is numbed, and the patient remains conscious. Once the anesthetist ensures that anesthesia has set in completely, surgery can be started.
Methods/Techniques of Knee Osteotomy
Knee osteotomy can be performed using the following methods:
A surgical incision is made using suitable instruments on the skin covering the affected knee. The muscles surrounding the joint, nerves and blood vessels are separated till the knee joint can be visualized. A chunk of bone from tibia (largest lower leg bone) or femur (only bone in thigh) corresponding to the diseased part of joint is dissected. In most cases, it is the tibia which is operated upon. The remaining ends of healthy bone are brought close together and secured with the help of metal screws, wires, nails or plates. This will realign the bone in such a way that pressure on the damaged part of knee joint is reduced. The muscles around knee joint are repositioned. Surgical incision is sealed using a medically designed thread.
A bone graft is needed for open osteotomy. The initial procedure is same as that in closed osteotomy. After a chunk is removed from either tibia or femur, the space is filled with a graft. But it is not completely closed. The bone is realigned in such a way that further damage to the knee joint is prevented. The cut edges of the bone are not brought together as opposed to what is done in closed osteotomy. They are left open. The skin incision is closed by stitching it with a medically designed thread.
These two methods differ slightly but have the same end result, i.e., restoring normal function of the damaged knee joint and preventing further damage. Knee osteotomy takes about 1-2 hours to be completed. It takes some weeks for the patient to completely recover after the surgery. During this period, some post-operative care instructions are expected to be followed by the patient.
After surgery, the patient is wheeled out of the operating room and transferred to an recovery room. Post-operative care begins as soon as patient is out of the effects of anesthesia. Some important post-surgical care instructions are mentioned below:
- Physical Examination: If the patient is placed under general anesthesia, it will take some time for them to regain consciousness. If regional anesthesia is used, the patient will still feel numb after surgery for some time. Once the effects of anesthesia wear off, the surgeon will examine the operated knee. The site of surgical incision might be slightly swollen and red immediately after surgery. This however subsides soon. Surgical incision is dressed with cotton and gauze. An antibiotic cream may be applied on it to prevent infection. The patient's operated knee is kept elevated so that there will be no pressure on the knee joint and there will be no fluid accumulation around the knee.
- Hospital Stay: After the surgery, patient will remain hospitalized for 2-4 days. During this period, the surgeon will check the knee at regular intervals. Weight bearing on the operated knee is restricted for some days after surgery. Later, depending upon the patient's recovery, gradual weight bearing may be started with the surgeon and physiotherapist's guidance. After 2-4 days, the patient may be discharged to go home. Home care instructions are explained to the patient and their family.
- Wound Care: The surgical incision has to be kept dry and clean all the time. For a few days after surgery, bathing is not advised. However, once the patient starts bathing, they have to take care to avoid letting the surgical wound get wet. The surgical dressing over the skin incision has to be changed regularly. Signs like bleeding, swelling, pain should be reported immediately.
- Weight Bearing: Weight bearing on the operated joint has to be strictly avoided for some days after surgery. For 4-6 weeks after surgery, crutches are to be used for walking. Later, a walker may be used to aid the patient while they walk. It will take about 8-10 weeks after surgery for the patient to start walking without any mechanical support. A knee brace might be provided during the initial few weeks after surgery. This will support the joint and prevent impacts of sudden movement from affecting the knee.
- Physiotherapy: As mentioned earlier, physiotherapy which is started prior to knee osteotomy is continued for a few months afterwards. Exercises, massage, hot/cold therapy, light therapy may be used singly or in combination for strengthening of the muscles around the operated knee joint. This is done to increase range of motion of knee and to regain balance while walking.
- Follow-up: During the first 6-8 weeks after surgery, patient is advised to visit the doctor at regular intervals for physical examination. The surgeon will examine the operated knee for range of motion, healing of surgical incision, strength of knee muscles. Once the surgical incision has healed, the sutures which were placed earlier to hold the skin together are removed. The skin will heal leaving a scar, which fades with time.
Following these post-surgical care instructions is solely for the patient's benefit. They will help the patient recover faster and resume normal activities.
Risks And Complications
Despite following all medical instructions properly, there is possibility of some complications during or after surgery. They are not harmful if they are diagnosed and treated on time. Some of these complications are mentioned below:
- Bleeding and Blood Clot Formation: When the knee joint is being operated upon, a blood vessel passing adjacent to the joint may get cut accidentally, which could lead to bleeding. The blood can collect in or around the knee joint and needs to be removed by draining it. If there is excessive bleeding, the lost amount can be replenished by blood transfusion. The accumulated blood could clot, in which case, the clots have to be mechanically removed. Smaller clots can enter the blood circulation if they enter some vein. To dissolve these clots, blood thinning medicines are prescribed.
- Infection: Infection can occur at the site of surgical cut or inside the knee joint after surgery. Persistent pain and swelling of the joint may be a sign of underlying infection. Antibiotic therapy is started for the patient to treat infection.
- Mal-alignment of the Bones: Sometimes despite the orthopedic surgeon's best efforts, the bone which was cut and restructured during surgery does not get aligned properly. In such cases, patient may experience difficulty while walking. The symptoms of arthritis may not resolve satisfactorily. Physiotherapy or another corrective surgery is utilized in such cases.
Like every surgery, knee osteotomy also has its own drawbacks. But if one calculates the benefit achieved from this surgery, it is much greater than the drawbacks.
Related information for Knee Treatment
- Information on Total Knee Replacement Surgery
- Information on Partial Knee Replacement Surgery
- Information on Knee Arthroplasty
- Information on Knee Arthroscopy