At Blackberry Clinic we treat a variety of painful conditions in the knee. Fat pad syndrome causes pain at the front of the knee and often presents in young women, or people with loose ligaments in the knee. Following a full assessment and diagnosis a course of treatment with a physio, osteopath or chiropractor could involve exercises and stretches, taping, orthotics and soft tissue massage. If improvement is not satisfactory there are injection options from our Sport and Exercise Medicine doctors and MSK doctors. The options are steroid injections or PRP injections. If you are suffering from symptoms of fat pad syndrome, don’t delay, book if for an assessment at your local Blackberry Clinic. MSK clinics include Milton Keynes, Guildford, Oxford, Croydon, Ipswich, Fareham, Lichfield, Birmingham and Brighton.
Acute or chronic inflammation of the Infrapatellar Fat Pad (IFP) is a common source of Anterior Knee Pain; also called Hoffa’s disease, fat pad syndrome or hoffitis.
Hoffa’s syndrome, also known as infrapatellar fat pad syndrome, is a problem which affects one of three pads of fatty soft tissue that lies under the kneecap (patella) and leads to pain at the front of the knee. The Hoffa’s fat pad acts as a protective cushion, which separates the kneecap from the shin and thigh bones. (ref physio-pedia.com)
The Infrapatellar Fat Pad is found in the anterior knee compartment as a mass of adipose tissue that lies intracapsular and extra synovial (extra-articular).
It is believed that the main functions of the fad pad are:
1. To facilitate gliding between the femoral condyles and joint capsule.
2. To support lubrication of the knee joint by facilitating the flow of synovial fluid inside the joint.
Knee efficient mechanics can be altered and compromised when there is a distortion in the fat pad (e.g.fibrosis, adhesion) that changes the position of the patella and patellar tendon.
Normally, when the knee moves into flexion (bends), the superolateral portion of the fat pad becomes relaxed and moves posteriorly.
In extension, the IFP lies between the lateral patella facet and quadriceps tendon.
Therefore, most commonly observed symptoms are associated with extension.
However, it could also be seen in in flexion, where pain is provoked by the trapped/impinged IFP between the patella tendon and anterior femur.
3. Two other features of the fat pad make it a difficult culprit.
Good innervation.
Fat pad is well innervated, mainly by the posterior tibial nerve, the irritated IFP can be a source of localised and severe anterior knee pain.
Fat is a producer and storage of immune cells.
The IFP is considered to be a producer of many inflammatory mediating substances found in association with OA. As an adipose tissue, IFP mainly secretes fatty acids which are known for their pro-inflammatory effects. Adipose tissue also stores immune cells, another potential source of inflammatory mediator substances. In addition, a study showed that IFP actively secretes IL-6 and its soluble receptor sIL-6R, at relatively higher levels compared to other adipose tissues.
Patho mechanics:
The anatomical location of IFP exposes it to mechanical load, especially during extension. Overuse or repeated micro trauma from sports or falls lead to hypertrophy. If the fat pad fails to recover it can become chronically inflamed which, if not properly managed, may result in fibrosis and ossification.
Risk factors:
Predominantly seen in young women, jumping sports and ligamentous laxity are also considered to be risk factors for Hoffa’s disease.
Diagnosis:
The inflamed fat pad is often enlarged, firm in consistency and easy to palpate. Hoffa’s test can be performed. This involves taking the knee into passive forced hyperextension by lifting the heel and keeping anterior pressure on the tibia. This position stimulates pain exclusively in the fat pad, if it is inflamed.
Signs:
Pain in hyperextension is a strong indicator of the presence of inflamed Fad Pad.
Symptoms of fat pad syndrome are anterior knee pain, often retropatellar and infrapatellar. Patellofemoral crepitus might be present, with knee loading such as in stairs walking, squatting, jumping and running.
Effusion and decreased ROM are often seen with inflamed IFP.
Pain due to long walks, flat shoes and prolonged standing may indicate Fat Pad Syndrome.
Whereas pain resulting from up or down hill/stairs walking, sits to stand, and discomfort in high heels is more characteristic of Patello Femoral Pain Syndrome (PFPS).
