Knee Joint:
Anatomy
Knee is amongst the strongest, largest and most complex joint in our body.
The knee joint is made up of the lower end of femur (thigh bone) upper end of tibia (leg bone) and patella (knee cap). The end of this bone is covered with smooth, glistering white padded substance called cartilage.
This cartilage is devoid of blood supply and nerve supply. The nutrition to this cartilage is obtained from the synovial fluid in the joint. The fluid also helps better lubricants and hence decreases friction.
The cartilage being devoid of nerve supply makes the movement pain-free.
Pathology
As cartilage erodes due to various reasons, most commonly spoken about is osteoarthritis and Rheumatoid arthritis, the underlying bones are exposed which are rich in nerve supply and hence pain starts. Inflammation (swelling and redness) and pain forms a visions cycle causing increased fluid in the joint: Pain, Swelling and Redness. To avoid pain the muscles go into spasm, and thus limit the range of motion of the joint. As the cartilage is damage more in one compartment of knee as compared to other, the deformity (Bowing) is seen.
This damage cartilage cannot be regained after 30 years and keeps deteriorating, cracking, wears away. Later the bones overgrow in the margins – called as osteophytes, which causes deformities and also stiffness of the joint. Thus the knee is now swollen, red stiff and deformed.
All this together makes walking difficult, increases the risks of falls secondary to the painful gait.
Total Knee Replacements / Total Knee Arthroplasty (TKR / TKA):
We basically recap (Resurface) the worn out cartilages with metal on the femur side and plastic (polyethylene) on the tibial side. The knee cap is also resurfaced with polyethylene.
Thus now once again, there is no bone to bone contact – so on PAIN, no swelling and no redness. The deformities can be connected as well as the range can be brought back.
In short, benefits of knee joint replacement-
• Reduction of joint pain.
• Increased mobility.
• Correction of deformities.
• Increased stability.
Risks involved in Total Knee Replacement:
Total Knee Arthroplasty / Total Knee Replacement though one of the most successful replacement surgeon is definitely a major surgical procedure and hence has few risk factors.
The best way to treat this is to avoid it. Complete aseptic precaution has to be taken.
- A thorough examination of the patient before posting for a knee replacement for any source of infection namely – dental checkup, urinary and stool examination, respiratory tract, GI tract skin infections etc.
- High standards and discipline in the Operation Theatre
I. A vertical laminar air flow is a must
II. Regular bacteriological swab is a must
III. OT doors should be shut throughout the procedure
IV. Body exhaust sent is mandatory
V. Remove excessive instruments in the OT.
VI. Fumigation, basiloid spraying before every replacement
VII. Double autoclaving of all instruments
VIII. Post-operative antibiotics - Post-operative antibiotics
If all above things are taken into consideration post-op antibiotics does not hold any important role. As a rule two days injectable antibiotics is enough.
2) Deep vein thrombosis (clot in the calf muscle)
It is best to avoid this complication, as its occurrence can change the mortality rate
of this surgery.
It is mandatory to use a low molecular weight Heparin the day before surgery and continue atleast till patient is mobilized. Elastic stockinet for atleast 4-6 weeks following surgery to reduce the blood clots in the legs.
Intraoperative and post-operative calf pumps can also be of great use if available.
3) Pneumonia
Pnemonia, a well known lung complication is seen in patients who have prolonged bed rest. This complication is best avoided by early mobilization out of bed. As a standard I generally mobilize the patient in bed on the same evening of surgery, and out of bed on the next day.
4) Malaligments, Continued pain after surgery, Instability
All this complications can
arise done to poor surgical skills.
5) Reduced range of motion
Can be caused due to poor elasticity of the soft tissues due to various diseased conditions, general life style of the patient, prolonged immobilization after the surgery, poor surgical skills, improper motivation and delay in physiotherapy.
1) Medical Evaluation:
- Laboratory test: Complete Blood Count
Urine routine and microscopic evaluation.
Renal function test
Liver function test
Bleeding and clotting profile – Prothrombin Time / Activated Partial Thromboplastin Time / Bleeding Time / Clotting Time.
Screening test – HIV I & II / HBsAg / HCV.
ECG
Stress test. (if some positive history regarding cardiac 2D Echo problems as specified by the physician) - X-Rays : X-Rays of Chest
- Doppler Studies of Both Calves’s to evaluate any pre-operative clots in the leg.
- Physicians fitness for the surgery after all the above investigation are done
- Special X-Rays of the involved Knee:
A full length single leg weight bearing X-Ray AP/
Lat view of the knee in 30o bending.
Merchants view to see the knee cap.
With the use of a tourniquet and good haemostasis, the blood
requirement in knee replacements is greatly reduced however a standby blood has
always to be arranged, . in case of emergency. Where ever possible auto transfusion is always recommended (i.e. giving the patient his own blood donated few days back – this decreases the possibility of blood transmitted diseases)
3) Home work
Some home work is required to make your life easier at home.
- Pre-operative hamstring and quadriceps building (www.boneandjointcare.net/physical therapy/knee exercises) helps the patient to walk much earlier even the next day of surgery.
- Arranging personal assistant to drive home after surgery, drive back for follow up and also help in shopping and errands.
- Arrange for a walker after surgery.
- Place all day to day items on a height to avoid excessive bending, kneeling and squatting which is way uncomfortable in the immediate postoperative period.
- Miscellaneous items like cordless phones, large aprons with pockets, bathing aids can make your post operative life more comfortable. Raising the height of your bed and sitting chair so that the knee doesn’t bend more than 90o makes getting up easier and painless.
- Set the list of all medication and important telephone numbers of your relatives
- Bring a walker, loose comfortable clothes, underwear, books, personal care items, cash for sundries.
- Don’t bring any expensive jewelry, large amounts of cash, credit cards or other valuable items to the hospital.
In the Hospital:
It is very important to handover the list of medications to the doctor which should involve Aspirin, Clopidogrel, Pain killers also. Some medications can complicate the procedures and increase bleeding. Some medications may have to be stopped in such cases, as per physician opinion.
Day of Surgery:
You will change into the hospital gown. Pulse, blood pressure is taken by the resident doctor. You are shifted to the pre-operative room, where intravenous line is gained and pre-anesthetic medications are given.
You will be later shifted to the operation theater and shifted on the operation table. This is the last thing you remember before waking up into the recovery room. Generally we prefer to give a combined epidural with spinal anesthesia with some sedation.
Recovery Room-
You generally experience chills or nausea which are the usual side effects of anesthesia.
In Your Room-
- You will notice a drain tube sucking excess unwanted blood out of the operated knee.
- Catheters – You will see
- Epidural catheter which is maintained in your back attached to a pump which maintance a constant flow which helps in pain control for a period of 72 hours after surgery,
- Foley’s catheter – (urine catheter)
- Pain medications- pain killers will be given as and when you feel necessary
- Elastic stocking – You may be given elastic stocking to be worn for 6 – 8 weeks following surgery which prevents blood clothing and improve circulation
- CPM (Continuous passive motion) helps bending of the knee and improves the range of motion, which can be used from the day of surgery.
Post - Operative Period:
TWO DAYS after Surgery
The drainage tube, IV cannula and urine catheter is removed.
Aggressive physical therapy is given in bending the knee progressively and walking with walker / crutches. Earlier the patient walks lesser are his chances of clots and other complications.
FIVE DAYS after Surgery
I generally prefer to see the patient packing up to go home on the 5th morning. Patient is sent home on calcium tablets, painkillers and LMWH.
I call them up on the 10th day from the discharge for the stapler removal.
You are requested to follow up later after 1 month, 6 months and then every year for a clinical and radiological evaluation of the joint.
LONG TERM care of your knee:
- Prevention of infection - As the knee is a foreign body it bears more risk of infection from other parts in the bodies. It is always better to start an antibiotic before you undergo any other procedure including dental procedure, report to the physician immediately if you suspect any infection.
- Weight control – lower the weight lesser will be the skin on the joint and hence lesser will be the wear
- Avoid high impact sports activities – walking, swimming, golfing or cycling can always be encouraged.
- Squatting, sitting crosslegged, climbing staircase has to be discouraged to avoid excessive wear of your joint.
Newer advances in Knee replacements:
Joint Reconstruction-
A new horizon for advanced osteo-arthritis
The traditional knee replacement consisted of cutting the quadriceps (quads) muscle tendon, with lot of tissue dissection and hence traumatic, resulting in a longer and more painful rehab protocol. Quads sparing surgery, also now known as MIS (Minimal invasive Surgery) has been the latest in the knee and hip replacements.
The quads tendon is the most important tendon which helps us to extend our knee and keep the leg straight, without buckling down in standing position. Till now the tendon had to be sacrificed partly in the knee replacement surgery. This cut was later stitched back. This resulted in lot of pain, in-front of the knee and delay in mobilization. The newer quads sparing approach, avoids the cutting of this quadriceps muscle so minimizes the pain. There is extremely minimal dissection of the other soft tissues also. To add to this an analgesic cocktail is also used during the surgery for an extended post operative analgesia. These helps faster rehabilitation and lesser pain after surgery. All this together has now made the post-operative period extremely comfortable and will definitely increase the patient’s compliance to replacement surgery. Many patients with advance osteo-arthritis will now dare to come ahead to undergo this procedure with better ease in the post-operative life.
Dr. Amey Velingker, the renowned Joint Replacement Surgeon attached to Apollo Hospitals in Goa achieved a landmark in knee replacement by making his patient walk in two hrs of surgery. The record breaking time is not just first in India, but in the world., a pride for every Goan! Mr. Tulsi Singh, CISF employee was the patient who did the unaided walking in just two hours of surgery. Mrs. Mohini Palyekar an advanced rheumatoid patient hailing from Mapusa, who had not walking normal for more than 10years due to the rheumatoid deformity of both her knee, could stand and walk pain free within 3hrs of the completion of the surgery. ( the videos with the testimonials are loaded on the www.youtube.com/dr.amey)
Mrs Deborah could do a Spanish dance on the third post-operative day; the video of this has received the highest rating on youtube, www.youtube.com/total-knee-replacement. The video also received special appraisals from joint replacement surgeons all over the world for the fastest mobilization to that extent. The live narrations and the walk before and after surgery is also available on the youtube.
The world record breaking post surgical result, of two hours walking after knee replacement, Dr. Amey Velingker concluded, was a team work of minimal surgical trauma, advanced instrumentations, minimally required anaesthesia, excellent post-operative analgesia and an aggressive and efficient team of physiotherapy.
Rotating platform knee-
Here the plastic of the tibia rotates on the metal backed tibial plate.
Advantage:-
Rotating platform mimics the normal knee movements, and hence supposes to last longer, as compared to normal knees, as the wear rate is less.
Disadvantage:-
The knee entirely relies on the external ligaments for stability and hence needs good ligament support. Hence has to be used in caution in diseases like Rheumatoid Arthritis, Psoriasis, etc.
Full flexion Knee:
It is a need of the Asian countries, where frequent squatting, sitting cross legged is a must in day to day life.
This knee can give bending of around 150 degrees as compared to the traditional knee bending to 130 degrees.