Knee Replacement - Benji Physio Post-op Classes
We see patients who recently had a knee replacement on a daily basis at the clinic.
Knee replacements are necessary when patients’ knee pain is such that most of their everyday activities are limited.
When will a knee replacement be required?
In most cases, a knee replacement is offered when patients suffers from knee osteoarthritis (OA) and their level of function are limited because of the pain. This option will also be offered to patients with rheumatoid arthritis (RA).
It is also possible to get a knee replacement following a fracture or major trauma to the knee joint.
Osteoarthritis (OA) Classification
The Kellgren and Lawrence classification system is often used :
grade 0 (none): definite absence of x-ray changes of osteoarthritis
grade 1 (doubtful): doubtful joint space narrowing and possible osteophytic lipping
•
grade 2 (minimal): definite osteophytes and possible joint space narrowing
•
grade 3 (moderate): moderate multiple osteophytes, definite narrowing of joint space and some sclerosis and possible deformity of bone ends
•
grade 4 (severe): large osteophytes, marked narrowing of joint space, severe sclerosis and definite deformity of bone ends
Patients will not automatically be offered a replacement if they suffer from an OA grade 3 or 4. The option to replace will mostly depend on the level of pain the patient is in.
A lot of knee pain caused by OA can be treated successfully by physiotherapy and weight loss.
Physiotherapy will consist on:
- Specific exercise programme to help strengthen the muscles around the joints, improve joint flexibility, bring pin relief.
- Pain relief with massage, acupuncture, shockwave therapy, corticosteroid injections.
Our Knee replacement class
Once a week we run a knee replacement class during which, under the care of a physio, you will be able to progress safely at your own pace towards your own personal post-operative goals. One a week for 12 weeks join us at the clinic, meet people you underwent the same operation and make the most of your op!
Types of knee replacements
There are two big groups of knee replacements.
• Total knee replacement TKR (Total arthroplasty)
• Partial (Compartmental) knee Replacement
Total knee replacement
Total knee replacement (TKR) is indicated when the OA affect more than one knee compartment.
In a TKR, 3 articular surfaces can be replaced:
The femoral condyles; the end part at the end of thigh bone (Femur)
Tibial plateau; the top part of your shin bone (Tibia)
Posterior aspect of patella; the back of your knee cap.
Implants fixation
There are different ways to attach knee implants to the bone.
• Cemented fixation
Implants are most commonly held in place with a fast-curing bone cement (polymethylmethacrylate).
• Cementless fixation
This technique will promote new bone growth into the surface of the implant.. Most implants are textured or coated so that the new bone actually grows into the surface of the implant.
• Hybrid fixation
A combination of cemented and cementless fixation is used.
Types of implants
There are different types of knee replacements devices.
• Posterior stabilized
Both the cruciate ligaments of the knee, the Anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL), are removed and the implant will provide protection against anterior-posterior gliding of the femur on the tibia.
• Cruciate- retaining
In that case, ACL is removed but the PCL is maintained if deemed healthy enough. The PCL will then keep its original function and limit the anterior-posterior glide of the femur on the tibia.
• Fixed Bearing
For this implant, the polyethylene (plastic) part of the tibial implant is fixed to the tibial metal implant limiting knee rotation.
• Mobile –bearing implant
At the opposite of the fxed-bearing implant, the mobile-bearing implant promotes knee rotation by allowing the polyethylene part of the tibial implant to mov on the metal implant.
All techniques have advantages and disadvantages and none has been shown to be better than another. The surgeon will choose which is the best for the patient.
Unilateral (compartmental) knee replacement (UKC)
When only one part of the joint is defective and painful, an unilateral knee replacement can be offered.
There are 3 types of UKC:
§ Medial compartment replacement
The medial femoral condyle and medial tibia plateau are replaced
§ Lateral compartment replacement
The lateral femoral condyle and lateral tibia plateau are replaced
§ Patellofemoral compartment replacement
The posterior aspect of the patella and the femoral groove.
The advantages of a UKC are
- Less pain
- Quicker recovery
- Decrease risk of infection and blot clot
Physiotherapy post knee replacement
At the hospital
Generally hospital physios will make you walk on Day 1 and bed exercises will also be given.
You should be discharged from hospital when the pain in under control, can walk safely with 2 elbow crutches (E/C) and walk up and downstairs (if you have stairs at home).
You are unlikely to be given further NHS physio unless you struggle after your operation.
At the clinic
We generally start rehab at the surgery once the stitches are out 10 days to 2 weeks post-op.
Our rehabilitation aim is to get the patient back a satisfactory level of function without pain. Different patients have different aims and goals after an operation and understanding them will guide the rehab protocol (and the overall duration of the physio treatment).
Benji Physio Rehab protocol will consist on
Education, Advice and Reassurance
Getting over a knee replacement is hard. It can be painful at times and patients often question their decision. One of the most important roles of the physio is help patients with the mental challenges thrown at you.
Exercises
Needless to say, exercises are the most important part of the rehab process after a knee operation. Not every patient needs exactly the same exercises, and our physios will prescribe the appropriate exercises for you and progress them as needed when you are ready to do so.
Hands-on?
Although not automatically offered, we will used hands on techniques if needed. We will for example, massage your quads, hamstrings and calves to help passive extension.
Scar massage can also be very useful to promote good scar healing.
Passive knee flexion and extension are also sometimes needed to improve the range of movement in your joint.
General expected outcome
Here is a list of activities we would expect you to be able to achieve within a certain timescale:
- Start static bike ASAP (2 to 4 weeks)- high seat – start with 5 min daily and inc as able
- Start modified Pilates within 4 weeks
- Long walk (3 miles +) – 2 to 4 weeks
- Kneeling 6 to 12 weeks
- Starting to feel that the operation was a success – 12 weeks (!)
- Outdoor cycling – 6 to 12 weeks
- Running 6 months+