MPFL reconstruction is an arthroscopic surgical intervention performed to address injuries on the medial patellofemoral ligament. The medial patellofemoral ligament works as a knee stabiliser and is pertinent in preventing knee dislocations.

It is found in the middle of the knee extending from the kneecap (patella) to the thigh bone (femur) thus, making up the patellofemoral joint. Injury on the medial patellofemoral ligament can manifest as a sprain or a tear commonly caused by patella dislocation (kneecap dislocation).  

Symptoms of MPFL include:

• Severely impaired walking and standing ability
• Swelling and bruising around the affected knee
• Inability to bear weight on the affected leg
• A sudden burst of severe pain at the time of injury

Some of the risk factors of medial patellofemoral ligament injuries include:

• Athletes: due to exposure to traumatic blows to the knee.
• Gender: specifically taller women, due to anatomical differences of the lower extremities.
• Age: children and teenagers tend to be more vulnerable.  
• Obesity: excess weight places stress on the kneecap.
• Prior injuries: one is prone to patellofemoral ligament injuries in recurrent patellar dislocations.

It is common for your orthopaedist to attempt recovery through conservative treatment. However, if patients present with second or third-grade injuries, an MPFL reconstruction would most likely be necessary.

MPFL reconstruction is also considered if you have a history of dislocations. It may be possible that a repair (sewing up tears) of the ligament is explored. However, reconstruction is a common treatment approach as they tend to be more effective. MPFL is an arthroscopic surgery in which an arthroscope is utilised.

In the event one has only had one dislocation or minor presentation of injury, surgery may still be considered if:

• Patients seek out urgent treatment for a speedy recovery; patients that are athletes tend to seek treatment with the quickest recovery rate.
• Conservative treatments prove ineffective. If the injury worsens and does not improve with conservation treatments, MPFL reconstruction surgery would be advised.

• Patient has other accompanying injuries such as cartilage injury.

MPFL reconstruction considerations will first be made at the diagnostic phase. Your orthopaedist would conduct reviews, tests, and an MRI to access the injury.

Two or three small incisions are made at the knee and an arthroscope is inserted, allowing your orthopaedic surgeon to visually assess the condition of your knee through the camera. This phase of the procedure is also known as arthroscopic diagnosis.  

The surgery is conducted in 2 parts– first, new ligaments are constructed to replace damaged ones, these are usually harvested from your hamstring. Next, the damaged ligament is replaced with a new ligament. The new medial patellofemoral ligament is held in place with screws or sutures.

On top of addressing MPFL reconstruction, other injuries that may have occurred such as chondral lesions will also be addressed during the surgery. The surgical site is then irrigated to prevent infections before it is closed either by suture or staples.

• Minimally invasive
• Quicker discharge
• Minimal scarring
• Short recovery period
• Prevents risks of dislocation and instability

MPFL reconstruction can be used to treat the following conditions:

• Bidirectional patellar instability: also known as patella subluxation/instability. It is a condition in which the patella (kneecap) slides partially or entirely out of its usual position in the trochlear groove of the femur (thighbone), producing discomfort and instability in the knee joint
• Patellofemoral instability: similar to patella subluxation, it is characterised by the sensation of the knee giving way.
• Knee dislocation: occurs when a significant force is exerted on the knee, causing the knee bones to be wrenched out of position, resulting in knee dislocation.
• Patellofemoral maltracking: also known as patella tracking disorder, it occurs when the kneecap is misaligned and feels like your kneecap is sliding out of position.
• Congenital anatomical abnormalities: knee abnormalities such as congenital knee dislocation or hyperflexibility are conditions that some individuals are born with.

Some of the results one can obtain from MPFL reconstruction include stabilised kneecap and the ability to return to activities participated in pre-injury.  However, you are still prone to future injuries if strict post-surgical care is not observed.

You will be relieved of symptoms that were previously evident, however, if this does not hold true for you, there may be complications such as loose bodies at the synovial membrane that needs to be inspected.

Additionally, athletes too would be provided with the opportunity to return to their preinjury sports without deterred performance. With the current success rate of 92.8%, the chances are definitely on the optimistic side, provided that dedicated rehabilitation measures such as physiotherapy are observed.

The recovery period varies depending on the grade of injury sustained. Depending on the individual, recovery could take anywhere between 6 to 9 months. Diets, habits, and dedication towards rehabilitation will play a role in the rate of recovery. With positive post-surgical care and collaborative work with your orthopaedist, you can expect a satisfactory outcome.

Results will vary from person to person, depending on the severity of the issue and your overall health. Your orthopaedist can give you a better idea of what to expect based on your individual needs and circumstances.

Arthroscopic MPFL is a one-off treatment.

However, treatment for ACL injury does not stop at surgery. To attain complete recovery, one will need to attend physiotherapy sessions and appropriately manage medications such as painkillers. The frequency of physiotherapy sessions will vary according to your personal goals such as the need to return to athletic endeavours.