Preparation prior to surgery

In order to prepare for joint replacement surgery a number of things should be considered.

Pre-existing medical conditions

You will be asked about your medical history. It is important that you accurately inform your specialist of any conditions affecting your heart, lungs, blood pressure, kidneys, or circulation.

It is also critical to inform your doctor of any conditions that may affect your immune system, such as diabetes. Patients will be assessed in a preadmission clinic prior to the surgery. The purpose of the premeasured clinic is to;

1. Obtain a thorough Merit medical and surgical history

2. Conduct any blood tests, x-rays, ECG, skin swabs and other investigations

3. Understand needs and answer your questions

Medications

10 days prior to surgery some medications need to stop. These may include aspirin, nonsteroidal anti-inflammatories, garlic capsules and fish oil. If you are taking blood thinners such as aspirin, Plavix, or warfarin these may need to stop but will likely need to be done in conjunction with the advice from either your general practitioner or another specialist such as a cardiologist. It is critical that you inform your specialist if you are taking these medications.

Skin care

It is vitally important that you have no cuts, scratches, or skin infections as these increase the risk of infection and may lead to your surgery been postponed. Do not wax or shave your legs in the week prior to surgery.

Smoking

It is recommended to cease smoking for at least 6 weeks prior to surgery. People who smoke have an  increased complication rate for events such as a DVT, infection, or wound complications.

Dental hygiene

Infections in other parts of the body can cause bacteria to go in to your bloodstream,  which can lead to a prosthetic joint infection. To reduce your risk of infection, major dental procedures should be done prior to you having any joint replacement surgery. If dental surgery is required following a joint replacement, you must inform the dentist that you are required to take a preventative antibiotic to minimise the chance of a blood-borne infection.

Day of surgery

Bring all x-rays and scans with you to the hospital.

You are usually admitted to the hospital of surgery where you will meet the anaesthetist who will discuss your medical and anaesthetic history. The anaesthetist will also discuss the type of anaesthetic being used during your procedure, which is most commonly a general anaesthetic.

On admission, your leg is washed, shaved if necessary, prepared with antiseptic and wrapped in a sterile towel. This helps prevent infection and helps identify the correct site for surgery. Prior to the surgery you will be repeatedly asked to confirm which side will be operated on. These are important checks for the hospital staff to perform.

The surgery

Intravenous antibiotics are given at the start of surgery. Surgery is performed with a tourniquet around the leg. An arthroscopy is performed to inspect the joint cartilage surfaces, remove any loose bodies and in some instances may be used to help guide the correction of the patella. If a tibial tubercle transfer is undertaken, this is done through an incision over the front of the tibia just below the level of the knee joint, a small piece of bone is cut and attached to the patellar tendon. Based off preoperative planning, the tubercle will then be transferred, usually medially, and in some cases will need to be moved distally. This is then fixed in position with 2-3 screws. The amount that the tibial tubercle is transferred will depend on intraoperative findings as well as preoperative assessment. In all instances, reconstruction of the medial patellofemoral ligament will be done. This can be done with allograft from a donor. If you have concerns about receiving donor graft, a tendon will be taken from you in the form of a hamstring tendon and used to fashion a graft that runs from the anatomical attachment point of the MPFL. These are attached to the patella usually via to bone anchors on the inner aspect of the patella. Two  limbs of the graft are tunnelled beneath the skin down to an attachment point on the inner aspect of the femur and this is confirmed using x-rays intraoperatively. This is typically fixed onto the femur with the use of a screw. In some instances, a lateral release will be performed. This is done to help improve the tracking of the patella and to release any tight structures.

At the conclusion of the procedure, local anaesthetic is infiltrated into the wound to reduce post-operative pain. Dressings are applied and a brace placed on the  leg.

After the Surgery

Pain relief is provided in the form of oral analgesia. Post-operative pain after an MPFL reconstruction is typically not severe. In some instances, the patient will be allowed to go home immediately if they are safe on crutches. The physiotherapist will assess you walking with crutches. You will be permitted to place some weight on your foot but the amount will be determined by the operation. Please refer to the surgeon’s instructions regarding this. The knee will typically be allowed to bend from full extension to 90 degrees flexion for the first 6 weeks.

Weight-Bearing

After surgery, weight-bearing will be determined by any meniscal and cartilage injury or associated ligament surgery. Typically patients are allowed to fully weight-bear with crutches. If weight-bearing is permitted, crutches are still required until the quadriceps have regained control of the knee and walking can be performed safely. Patients typically go home the same day of surgery.  

Bandages and Dressings

On the first after surgery, the bandages on the knee are removed and a compressive bandage called a tubigrip, which has been placed underneath from mid shin to mid-thigh, is left in place. The dressings are kept dry and in place until the wound review, which is performed with the surgeon typically 10 to 14 days after the surgery. If the bandaging becomes soaked either with blood or otherwise the patient should return either to the clinic, or if this is not possible, to the hospital to have the dressings changed.

Stitches in the incisions may be dissolving, however are sometimes still removed between days 10-14 on a return visit to consultation for a wound review. The knee needs to remain dry. Swimming, bathing, spa’s, sauna etc. is not allowed until wound healing is confirmed. In order to shower, a water-proof sleeve that fits over the knee can be purchased from the chemist.

• Waterproof dressings have been applied to the skin that allow patient to shower

• Small amounts of ooze that can be seen on the dressings are a normal part of the routine post operative experience and are of no concern.

•  If there is a larger amount of blood that leaks from a dressing, this is very rare. Over wrap the area with 2 x extra crepe bandages with a firm pressure. Rest the knee and avoid excessive walking. Contact Dr Shatrov' Practice Manager at the next available time so an urgent review can be arranged. 

Exercises

Exercises to activate the quadriceps and gluteal muscle are performed, and calf pumping exercises encouraged to circulate blood throughout the leg. The focus initially should be on achieving full extension of the knee and activating the quadriceps muscles. Flexion of the knee is typically encouraged as well but may be limited depending on some of the associated injuries or surgery that your knee may have required such as meniscal surgery.

Medications

A blood thinning medication is often prescribed for two weeks following surgery to reduce the risk of DVT’s. 

Pain relief is prescribed and typically involves the following; 

• Paracetamol 1 g every 6 hours (if the patient does not have either an allergy to this medication or pre-existing liver disease) 

• A nonsteroidal anti-inflammatory which is typically either 1 of celecoxib, meloxicam or Volatren. This should not be taken if the patient has kidney problems, high blood pressure, may be pregnant or has reflux. 

Additional pain killers are often prescribed but depend on a variety of factors including the anaesthetist’s preference, the patient's preference, and pre-existing medical conditions as well as their medication history. Local anaesthetic is typically injected around the incisions and graft harvest site at the time of surgery and often wears off 12 to 18 hours after being inserted. This is often accompanied with gradually increasing pain at that time. Medications are to be purchased upon discharge from the hospital. Ongoing scripts if required should be sort from your GP.

Driving 

Driving is not permitted until sufficient muscle control has been regained to allow for emergency breaking. The length of time that this takes varies depending on the surgery, and can range from 1 week to 3 months. Driving is also not needed whilst taking certain medications. For more information about this please consult either your general practitioner or your orthopaedic surgeon.

Showering

Showering is permitted but the wound needs to remain dry. A sleeve can be purchased from some chemists. Alternatively, a bag can be wrapped around the leg in order to keep it dry.

Bracing

Bracing is not performed routinely however may be required if MPFL surgery is performed in conjunction with other associated injuries such as meniscal repair, bony procedure  or additional ligament surgery.

Physiotherapy

A critical component of MPFL recovery is a supervised rehabilitation program with a physiotherapist. Physiotherapy should be arranged prior to surgery and the details of the physiotherapist shared with the surgeon so they can communicate as required during your recovery. The frequency and duration of therapy will be determined by the physiotherapist but should commence within a week of the surgery.

Rehabilitation

Following discharge from hospital, you will see Dr. Shatrov 2 weeks after the surgery for a wound check.  If any bone surgery has been performed, an x-ray will be performed 6 weeks after the surgery to check that the bone is healing. At this point, the brace is typically removed and physiotherapy is increased.

It is important initially that you do not start quadriceps exercises until the transferred bone has healed in position and this usually takes 6 weeks. This is done by typically ensuring that the leg is locked in full extension when weight-bearing. It’s  important to note that this will only be the case if you had a tibial tubercle osteotomy. If you have not had this procedure, this information will be different.

In the first 6 weeks, the aim of the physiotherapy will be to activate quadriceps and hamstring muscles, improve the range of motion, reduce the swelling and to perform calf pumping exercises.

Potential Risks and Complications

Infection. 

Although great caution is taken before, during, and after surgery, infections can occur in approximately 1 to 2% of cases. Deep infection in the bone is rare but if this occurs and is untreated, serious problems can follow. If an infection occurs, please contact the rooms immediately or present to the nearest emergency department. In the presence of a deep infection, surgery may be required to irrigate and close the wound, and long-term antibiotics may be required. Any fever, wound redness, swelling or increasing pain should be reported to Dr. Shatrov.

Blood clots

Deep vein thrombosis, or DVT, can occur when the veins in the leg form blood clots which, in some instances, can dislodge and travel to the lungs and cause something called a pulmonary embolism. A pulmonary embolism, whilst very rare, can be fatal and this is to be taken seriously. The following steps will be taken to avoid blood clots

• Early mobilisation

• The use of compression stockings

• Foot and ankle pumping exercises every hour whilst awake to increase the blood flow and reduce venous stasis in the leg

In some instances, you will be given a blood thinning medication post-surgery. If you develop abnormal swelling, redness, pain or tenderness in the calf muscle, chest pain or shortness of breath, the symptoms should be immediately reported to Dr. Shatrov.

Poor bone healing

In approximately 2 to 3% of patients, the bone may not fully heal or may change position whilst healing. This is monitored by x-rays. Occasionally, further surgery may be required to improve or expedite bone healing. Poor bone healing is much more common in people who smoke or who have other medical comorbidities that may impair healing.

Nerve and vessel injury

Several major nerves and blood vessels which supply the legs are in the vicinity of the surgery and are at risk at the time of the operation. This is an extremely rare complication. More commonly, a couple of small nerves that supply the skin in the region will be divided at time the surgery and a small numb patch in the lower leg is common after the surgery. This is typically permanent. In the case of nerve injury, it is possible that if this occurs, the patient may lose the ability to move the foot up and down.

Haematoma

A haematoma is a collection of blood. In the knee, it may occur after surgery. It is more common if the patient takes blood thinners. It can be a source of pain and stiffness. It can be treated by aspiration or via the use of ice and compression.

Other possible complications

It is common for people to find difficulty initially improving their range of motion in the knee and experience some stiffness particularly extending the knee. This is the purpose of physiotherapy after surgery.

Further progression of osteoarthritis

It is important to understand that the surgery will not take away any pre-existing osteoarthritis. It is an expected outcome following a high tibial osteotomy for an osteotomy of the lower leg but eventually at some point the patient will progress to needing further surgery to deal with the symptoms of osteoarthritis.

Patella fracture

It is possible that fracturing the patella following the surgery can occur. This typically occurs due to a direct blow or a fall onto the leg. This is a rare but potentially serious complication as it may require further surgery to  be undertaken. It is important that you  do not return to contact sports for at least 6 months following surgery.

Results

Most patients experience good outcomes following patellar stabilisation surgery. The patient can eventually return to sport, typically 6 months after the surgery. The literature suggests that approximately 7 to 10% of patients may experience further episodes of instability following MPFL reconstruction surgery. Approximately one third of patients will progress to developing osteoarthritis of the patellofemoral joint. This number is about 70% without surgery.

Dr Shatrovs Publications on Patella Instability Surgery

1. Shatrov J, Vialla T, Sappey-Marinier E, Schmidt A, Batailler C, Lustig S, Servien E. At 10-year minimum follow-up one-third of patients have patellofemoral arthritis following isolated medial patellofemoral ligament reconstruction using gracilis tendon autograft. Arthroscopy. 2022 Aug 18:S0749-8063(22)00483-2. Doi: 10.1016/j.arthro.2022.07.021. Epub ahead of print. PMID: 35988794.

2. Shatrov J, Colas A, Fournier G, Batailler C, Servien E, Lustig S. Can Patella Instability After Total Knee Arthroplasty be Treated With Medial Patellofemoral Ligament Reconstruction? Arthroplasty Today. 2022 Jun 4;16:130-139. doi: 10.1016/j.artd.2022.04.006. PMID: 35677944; PMCID: PMC9168055.

3. Shatrov J, Colas A, Fournier G, Batailler C, Servien E, Lustig S. Tibial tuberosity osteotomy and medial patellofemoral ligament reconstruction for patella dislocation following total knee arthroplasty: A double fixation technique. SICOT J. 2022;8:23. doi: 10.1051/sicotj/2022023. Epub 2022 Jun 14. PMID: 35699459; PMCID: PMC9196027.

4. Erard J, Olivier J, Gunst S, Shatrov J, Batailler C, Lustig S, Servien E. Nonanatomical femoral tunnel positioning in isolated MPFL reconstruction is not associated with an increased risk of patellofemoral osteoarthritis after a minimum follow-up of 10 years. Knee Surg Sports Traumatol Arthrosc. 2024 Nov;32(11):2806-2817. doi: 10.1002/ksa.12264. Epub 2024 May 20. PMID: 38769805.