With sports seasons in full swing, we’re starting to see an influx of patients coming in with knee pain, ranging from acute injuries to pain stemming from overuse. For a joint that only bends and straightens, the knee can present quite a number of different issues. That’s why we’ve decided to prepare the P360 Guide To Knee Pain!
This guide will cover the most common knee presentations we see in clinic and how to recognise them. To simplify things, we’ve categorized the various conditions by their location, that is, pain in the front, back, or sides of the knee. In Part I, we’ll be looking at pain in the front of the knee!
- Gradual onset of pain
- Pain with jumping or landing
- Pain directly on the tendon or bottom point of the kneecap (patellar tendinopathy)
- Pain directly above the top of the kneecap (quadriceps tendinopathy)
- Morning stiffness
The patellar tendon connects the kneecap (patella) to your shin bone (tibia), and is heavily involved in jumping activities. Most patients tend to experience issues with their patellar tendon following an increase in their training load (e.g., more frequent training sessions, going from off-season to pre-season). Due to its association with activities involving jumping, it is also known as “jumper’s knee”!
The quadriceps tendon connects the quadriceps muscle on the front of the thigh to the kneecap, and sits above the patellar tendon. In terms of its presentation, it shares many features with patellar tendinopathy and is usually aggravated by the same activities. Both conditions are treated very similarly since they are functionally part of the same chain of structures!
Osgood-Schlatter disease and Sinding-Larsen-Johansson syndrome
- Gradual onset of pain
- Pain with running, jumping, landing, kicking
- Enlarged bump near the top of the shin bone (Osgood-Schlatter disease)
- Pain on the bottom point of the kneecap (Sinding-Larsen-Johansson syndrome)
If OSD and SLJS sound exactly like the tendinopathies described above… you’re right! OSD and SLJS are the paediatric equivalents of those conditions. Due to differences in bone maturity, peak stresses tend to be concentrated in the areas where tendons join to the bones instead of in the tendons themselves, resulting in slightly different areas of pain.
In OSD, the pain is localized to the tibial tuberosity, or the bump high up on the shin bone below the kneecap. In SLJS, the pain is localized to the bottom point of the kneecap.
It was previously thought that OSD and SLJS were just “growing pains” and that children would just grow out of it, but we now know that both conditions can be treated successfully, allowing children to continue sport!
Patellofemoral pain syndrome (PFPS)
- Pain with squatting, stairs, or sitting down (“knees over toes” movements)
- Gradual onset of pain
- Pain is felt behind the kneecap
Like the tendinopathies described above, patients tend to report an increase in loads prior to the onset of PFPS. Unlike tendinopathies, however, the pain in PFPS can be difficult to localise; many patients are unable to pinpoint a specific location of pain on the knee, or will report feeling it somewhere behind or underneath the kneecap.
Unlike other types of knee pain, PFPS is not associated with a particular structure in the knee (e.g., not a problem specifically with a tendon, ligament, or other structure). In addition to a sudden increase in loads, other factors such as the function of joints above and below the knee (i.e., hips and ankle) and even footwear may play a role in the onset of PFPS! It’s important to have a thorough assessment to identify what issues could be contributing to your knee pain so that treatment can be tailored specifically to you!
- Feelings of instability around the kneecap
- Pain or instability when going up or down stairs, jumping, running
- Kneecap that sits off-centre on the knee (too far to the side or too high)
People who have patellofemoral instability tend to report lacking confidence when weight-bearing or pushing off through the affected knee. Patellofemoral instability can be due to genetic factors, such as the natural position of the kneecap. This condition may also result from a previous traumatic dislocation of the kneecap, leading to laxity in the ligaments that usually hold the kneecap in place.
Fat pad syndrome (Hoffa’s syndrome)
- Pain behind or around the patellar tendon
- Worse when the knee is completely straight
- Pain is worse with walking than with running
Hoffa’s fat pad is a pad of fatty soft tissue that sits just behind the lower part of the kneecap and patellar tendon. The fat pad acts as a cushion, which pads the kneecap from the thigh and shin bones. Sometimes, the fat pad can become irritated through repetitive movements, sudden trauma (blow to the front of the knee) or prolonged pressure, leading to inflammation and pain.
- Pain and swelling in the knee that worsens with activity
- Feeling like the knee “gives way”
- A loss of knee bending or straightening range of motion
- A locking or catching sensation in the knee joint when bending or straightening
Osteochondritis dessicans (OCD) is a serious condition that occurs when a small segment of the bone separates from the end of the bone that forms the joint. This happens due to a lack of blood supply, leading to death of the separating bone tissue. As this bone tissue dies, the cartilage covering its surface can crack and may break loose, leading to a blockage within the joint.
OCD mostly affects children and adolescents as their bones haven’t fully matured, but can also affect adults in some instances. OCD usually happens when there is repetitive trauma or stress to the bone over time, such as from playing sport. Due to its seriousness, it’s important to be vigilant for any of the above symptoms so early action can be taken!
What should I do if I think I’ve got one of the above?
Early diagnosis and treatment can help prevent worsening of your symptoms and get you back to doing the things you enjoy. The majority of the above conditions can be managed without further intervention, meaning physiotherapy treatment is sufficient. Depending on your condition, your physiotherapist will help devise a treatment tailored specifically to you to help you achieve your goals!