INJECTION THERAPY FOR FAT PAD IMPINGEMENT

What is fat pad Inflammation?
Inflammation of the fat pad in the knee can occur on its own or in conjunction with other knee problems such patella tendinopathy or patellofemoral (knee cap) pain. The majority of the fat pad can be felt as a’spongy/soft’ zone beneath the knee cap. Hoffa’s fat pad is another name for it. It can become inflamed if you directly bang/knock your knee (e.g. falling onto your knee), or it can become inflamed as a result of overuse. It is most frequent in active people, especially dancers and those who have to kneel as part of their employment (for example, carpenters), although it can also affect runners and footballers. Fat pad inflammation is best diagnosed with an MRI scan.

Physiotherapy is the first-line treatment for fat pad inflammation, and if the pain is severe, it will likely include a period of taping and activity reduction, followed by rehabilitation to strengthen weak muscles around the knee. It is not uncommon, however, for an ultrasound-guided injection to be necessary to reduce inflammation, and this should be considered if discomfort persists. A steroid injection can relieve pain quickly and hasten your recovery.

What are the symptoms of fat pad inflammation?
The most common symptom is pain on the front of the knee below the knee cap.

  • Kneeling activities, as well as impact activities that require repetitive bending and straightening, such as jogging and dancing, worsen pain.
  • When you press the’soft/spongy’ region on the front of the knee, right below the knee cap, you will experience pain.
If this sounds like your issue, keep reading…

Other conditions that mimic fat pad Inflammation?

 

  • Meniscal (cartilage) tea
  • Knee osteoarthritis
  • Pain in the patellofemoral (knee cap) joint
  • Bursitis of the prepatella
  • Tendonitis of the pes anserine
  • Patella tendinopathy (jumper’s knee).

Fat pad Inflammation vs Patellofemoral pain
Localized pain at the front of the knee and tenderness (pain when you press it) behind the knee cap are symptoms of fat pad inflammation. Patellofemoral joint discomfort, on the other hand, generates a more widespread (generalised) ache on the front of the knee, with no specific sore places. Because the irritation/pain is originating from under the knee cap, this is the case.

Squatting, prolonged walking, and moving downhill worsen fat pad inflammation and patellofemoral knee joint pain. In fact, they frequently occur together and can be difficult to distinguish. An MRI scan can help you figure out what’s causing your knee pain.
Anatomy of the infrapatellar fat pad
 The infrapatellar fat pad (also known as Hoffa’s fat pad) is found near the front (anterior) of the knee joint. It’s a big structure that sits between the patellar tendon and the knee cap. It’s the soft portion under your knee cap that you may push at the front of your knee.

Because of its abundant blood and nerve supply, the infrapatellar fat pad is extremely sensitive and is thought to be a major source of discomfort in many knee problems. It is encased within the knee joint capsule and is inextricably related to both the meniscus (knee joint’s shock-absorbing cushion) and the joint capsule’s inner lining (Bennell et al., 2004). The synovial membrane is the inner lining of the joint and is a common site for inflammation and pain. Synovitis refers to an inflamed synovium. Synovitis can cause pain in the front of the knee (Dragoo et al., 2012).

The infrapatellar fat pad’s exact function is unknown, however it is thought to operate as a reservoir for cells utilised to rebuild the knee following an injury. It’s also suggested to play a function in the knee’s shock absorption and mechanics during movement (Dragoo et al., 2012).

What causes infrapatellar fat pad impingement / inflammation

When the infrapatellar fat pad becomes impinged (pinched) between the patella (kneecap) and the femoral condyle, fat pad impingement occurs (large bony prominence at the end of the long bone of the thigh). Microtrauma occurs within the fat pad as a result of impingement, resulting in pain, edoema, and inflammation. The healing process is disrupted when the fat pad swells, resulting in fibrotic alterations inside the fat pad. This, in turn, leads to more impingement episodes, creating a vicious cycle of pain, swelling, and impingement (Bennell et al., 2004).
  • Impingement of the infrapatellar fat pad can arise for a variety of reasons, including:
  • When running and kicking a ball in football, the extensor (quadriceps) mechanism is overloaded.
  • In gymnastics/dance, hyperextension of the knee (excessive straightening of the knee) is common.
  • Carpet layers are prone to kneeling on a regular basis.
  • After a fall, direct impact to the front of the knee.
  • Poor biomechanics — this is common in runners due to weak hip muscles or a flattened (pronated) foot arch.

However, other linked knee issues are the most common cause of infra-patella fat pad inflammation/impedement that we find at Joint Injections. Because of its close ties to the knee joint, the infrapatellar fat pad is frequently linked to:

  • Osteoarthritis
  • Pain in the patellofemoral joint
  • ACL and meniscal tears are examples of ligamentous injuries.
  • Patella tendinopathy is a condition that affects the patellar tend
  • Post-operative pain after arthroscopy/keyhole surgery — During arthroscopy/keyhole surgery on the knee, the surgeon passes his instrumentation through the fat pad. This can result in long-term pain and inflammation following surgery. (Draghi and colleagues, 2016).

Clients frequently come to the clinic with a diagnosis of one of the foregoing illnesses based on an MRI scan or X-ray, only to discover that their pain is caused by the infra-patella fat pad.

How do you know if you have infrapatellar fat pad impingement / inflammation?

Inflammation/impingement of the infrapatellar fat pad is a common cause of anterior knee pain, and it’s typically linked to other knee problems.
Inflammation of the infrapatellar fat pad can cause the following symptoms:

  • The front of the knee has a sharp discomfort.
  • Surrounding the patella and the patellar tendon is swollen.
  • Long periods of standing or sitting with crossed legs cause pain.
  • Walking and squatting cause pain.
  • Sport-related pain Running and kicking activities, in particular.
  • Wearing high heels causes pain.
  • After periods of rest, such as getting up first thing in the morning or sitting at a computer, pain can occur.

How is an infrapatellar fat pad impingement diagnosed?

A clinical examination and diagnostic imaging are used to make the diagnosis of infrapatellar fat pad inflammation/impingement.

The evaluation entails:
1.A clinical interview is used to determine how your pain began and what circumstances may have contributed to its progression. In addition, a complete medical history is collected. This is to rule out any other factors that could be contributing to your discomfort, such as systemic inflammatory illnesses like rheumatoid arthritis.

2. A physical examination, which involves

  • Testing the range of motion of the knee joint.
  • Strengthening of the quadriceps and hips.
  • The structures of the knee joint are palpated (felt). This can be a little unpleasant at times, but it’s crucial to find the structure that’s causing your issues.
  • Movement tests are performed. Squatting, lunging, single-leg balance, walking, and running are all common functional tests.

Imaging for diagnostic purposes

Although a clinical examination can provide useful information about your illness, diagnostic imaging is required to confirm the presence of an infrapatellar fat pad impingement. A magnetic resonance imaging (MRI) scan is the best way to see fat pad impingement/inflammation. Soft tissue pathology is frequently diagnosed with MRI, which is an excellent diagnostic technique. An MRI is a time-consuming procedure that might take anywhere from 30 minutes to an hour to complete. This entails lying still within the machine while it captures a series of photos. From front to back, the sequence of photos gives a comprehensive view of your knee.

Ultrasound imaging for diagnostic purposes

Diagnostic ultrasound can produce real-time dynamic pictures of superficial soft tissues and can also be utilised to administer injections using ultrasound guidance.

Because the infrapatellar fat pad is a superficial structure, it may be examined quickly and correctly using this imaging approach. Diagnostic ultrasound imaging is useful for detecting persistent fibrotic alterations in the infrapatellar fat pad, as well as synovitis-related inflammation. A technique known as power Doppler is used to visualise inflammation within the fat pad. Ultrasound imaging can be used to see inflammation within the fat pad during this procedure.

How do we treat with infrapatellar fat pad impingement / inflammation?

A large percentage of patients with infrapatellar fat pad impingement/inflammation react well to physiotherapy treatment.

The following are frequent physiotherapy treatments for infrapatellar fat pad impingement:

  • Giving advice on how to prevent exacerbating symptoms.
  • Create a rehabilitation programme that focuses on strengthening the muscles that surround the knee and hip.
  • Prescribe a sequence of stretches for tight musculature in the lower limbs.
  • Re-education of improper movement patterns and biomechanics — this may entail altering your walking, running, squatting, or lunging technique.
  • Your physiotherapist may occasionally use therapeutic tape to support your knee, which is aimed to reduce symptoms by offloading the fat pad.
  • Acupuncture and soft tissue treatment techniques are occasionally utilised to assist reduce pain and tightness caused by your symptoms.
  • If your foot has been diagnosed with over-pronation, you should seek advice on footwear and orthotics.

What if conservative management does not work?
If physiotherapy and a progressive home exercise regimen have failed to relieve your symptoms, an ultrasound-guided injection may be recommended.

Using real-time ultrasound guidance, a modest dose of a potent anti-inflammatory medicine known as a corticosteroid is coupled with a short-acting local anaesthetic and injected into the infrapatellar fat pad. Ultrasound-guided injections have been shown to be much more accurate than landmark-guided injections at delivering medication to the intended target. This enhanced rate of accuracy also leads in fewer post-injection problems, is more tolerated by patients, and can provide significant pain relief, according to research.

A corticosteroid injection guided by ultrasonography is not a stand-alone treatment. The pain reduction provided by a corticosteroid injection provides you with a ‘window of opportunity’ to begin a rehabilitation programme. Joint Injection strongly advises that you begin a course of physiotherapy within two weeks of receiving your injection, once your pain has subsided.

Corticosteroid is an excellent medicine for relieving discomfort and inflammation caused by infrapatellar fat pad impingement, and is especially useful in the following situations:

  • If your discomfort has persisted for more than three months or is becoming worse.
  • If your pain is preventing you from sleeping and wakes you up.
  • If your discomfort is interfering with your ability to do everyday tasks, work, or engage in recreational activities, you should seek medical help.
  • If your pain is interfering with your ability to complete your physiotherapy programme.
  • Joint Injections can provide ultrasound-guided steroid injections on the same day. A highly trained team of clinicians, including fully licenced physiotherapists, musculoskeletal sonographers, independent prescribers, and injectable therapists, has made this feasible. Not only will you receive a formal diagnosis at your initial evaluation, but your doctor may also administer an ultrasound-guided injection if necessary. You have the option to self-refer to our service. You do not need a referral from your doctor, and you do not need to carry a prescription with you.

Joint Injection’s experts are dual-trained, highly specialised physiotherapists and musculoskeletal sonographers with extensive experience diagnosing all knee disorders. We provide a ‘one-stop’ clinic, which means you’ll get an examination, a diagnostic ultrasound, and, if necessary, an ultrasound-guided injection.