Understanding Knee Pain: A Complete Guide to Common Injuries

Knee pain is one of the most common complaints among active individuals and the general population alike. In this comprehensive guide, we combine seven in-depth articles that explore the most frequent causes of knee pain from patellofemoral pain syndrome to ligament injuries and chondral defects.

Each section covers causes, symptoms, and treatment approaches, alongside professional insights from the author. You will gain a better understanding of each condition, practical advice for management, and guidance on when to seek professional consultation.

Table of Contents

Part 1 Anterior Knee Pain

Knee pain can result from a number of different structures and in a variety of ways. In this series of articles we shall look at the more common complaints and deal with each condition separately.

The following injuries will be explored giving views by various authors and with an overview by this author giving his opinion based on a lifetime of experience in Sports Therapy:

• Patello-Femoral Pain Syndrome (Anterior Knee Pain)
• Ilio-Tibial Band Syndrome
• Osgood Schlatters Disease
• Patella-Tendonitis (Jumpers knee)
• Knee ligament injuries
• Meniscus injuries (Cartilage)
• Patella dislocation
• Bone injuries (fractures, pitting, bruising)

There is a small rotational component in the knee joint and some glide forward and backward between the Femoral Condyles and the platform made by the Tibia as in the diagram below.

A look inside the knee (WebMD, LLC 2010)

The Quadriceps Muscles attach to the Patella (Knee cap), which in turn is attached to the Tibial Tuberosity on the Tibia (shin) via the Patella tendon. 5. 6. Although in action it produces a simple movement the knee joint is one of the most complex structures in the human body. This complexity gives rise to the potential for injury but also makes diagnosis problematic for the medical team.

So for the first injury in our series we’ll look at:

Patello-Femoral Pain Syndrome (Anterior Knee Pain)

PFPS – What is it?

Patello-Femoral Pain Syndrome (PFPS) is a painful condition where the patella (knee cap) rubs on the Femur (thigh bone) in such a way that pain and sometimes swelling is produced. 11. The Patella is meant to glide over the Femur and is equipped with a hard shiny covering over the bones in both areas to facilitate this glide. This Hyaline Cartilage, as the hard shiny surface is called, reduces friction at the point of contact. 12. However things can go wrong.

PFPS – What causes it?

The under surface of the Patella has a “V” shape to it that corresponds with a reciprocal groove in the Femur as in the X-Ray image below (taken from above the knee looking down).

X-Ray image of the knee from above (Essex Knee Surgery, 2008)

As the knee is extended and flexed the Patella glides over the Femur along the line of this groove that extends from the front of the Femur to under the distal Femur. In standing the Patella sits at the top end of the groove but as the knee is bent such as when squatting, the angle of the Femur changes and the Patella sits more on the under surface of the Femur. 11. 13. All is well if this mechanism functions correctly and there is no trauma to either bony surface. However several factors may cause changes. 3. 7. 11. 12.

These include:

• Biomechanical factors
• Muscular factors and
• Overuse factors

1) Biomechanical Factors

Of the biomechanical factors some of the more common issues in available literature include the following:

• Altered tilt of the Patella
• Rotation of the Patella
• Mal-tracking of the Patella
• Altered Q angle
• Pes Planus – flat feet or over pronated feet
• Pes Cavus – high arch over supinated feet
• Knee valgus or varus – knock knees or bow legged

Small changes to the tilt or rotation of the Patella reduce the contact area between the Patella and the Femur. 14. Over time this produces a “hot spot” of pressure causing the hyaline cartilage to abnormally wear.

Mal-tracking of the Patella occurs when for a variety of reasons the Patella does not track accurately in the groove of the Femur. Most commonly the Patella tracks laterally (towards the outside of the knee) causing a friction to occur between the under surface of the Patella where it rubs on the hard ridge of the Femoral Condyle. 13. 15.

Altered Q angle has been postulated as a biomechanical cause, particularly in females.

This is the angle between the width of the hips and the alignment of the knees in relation to the vertical. Excessive Q angle is proposed to increase lateral pull on the Patella. 2. 10.

Pes Planus and Pes Cavus are thought by some to have an effect on the knees. The biomechanical effects are postulated to change the Patello-Femoral function thereby causing PFPS. 2. 3. 4. 7. 8. 9.

Knee Valgus and Varus similarly are possibly factors contributing to Patello-Femoral function.

2) Muscular Factors

Muscles exert a pull on the bones in order to produce movement. If the Quadriceps Muscles exert an uneven pull on the Patella then it is postulated that this could alter the Patello-Femoral function. 1. 2. 6.

The most common theory for PFPS is that the Vastus Medialis Obliques muscle is weak and therefore does not balance the pull exerted by the other Quad muscles and laterally mal-tracks the Patella. 6.Tightness or muscle imbalance between any of the muscles of the leg is also thought by many to be a causative factor. 1. 5. 6.

3) Over Use Factors

As the term implies excessive activity is proposed to cause PFPS.

The tissues of the body are designed to accommodate to the stresses applied to them by getting stronger. By lifting weights the muscles adapt over time by increasing mass and therefore tensile strength. Similarly the bones, ligaments, heart and other tissues adapt in the same way. 

This tissue adaptation is the process all sportsmen and women go through to get fitter for their activity, however when these stresses are applied before the body has had time to make adaptations then the tissues can break down. It is therefore postulated that too rapid an increase in activity may cause injury including PFPS. 16.

PFPS – What else could it be?

There are several other factors which could cause knee pain. Some of these require more sophisticated equipment such as X-Rays, MRI’s or bone scans to determine the cause of pain. Dislocation of the Patella (as in the picture below) or Patella subluxation, stress fractures, bone bruising, bone defects, or pathological conditions such as Osteoarthritis all have the potential to cause knee pain and should not be lightly dismissed. 4. 7. 11. 14. 16.

(Body in Motion, 2010)

The plethora of potential causes of PFPS is quite bewildering. There seems little consensus by medical experts as to the causes of PFPS and therefore the treatments prescribed are even more numerous. In a recent blog on a website of a particular medical profession as many as thirty-four different treatments were prescribed for PFPS.

In other medical professions there may well be just as many treatments prescribed. Whilst it must be accepted that there could be multifactoral causes in any one individual and that between individuals the causes may vary, there are nevertheless too many “red Herrings” proffered by medical professionals albeit in an honest attempt to solve PFPS. Trial and error seems to be the norm but this can be costly, time consuming and frustrating to the injured individual.

We would like to pose some questions to those who are encountering this trial and error pathway for their particular knee pain:

• Was there a single traumatic event that caused the knee pain or did it come on slowly?
• Does the pain intensity vary from day to day or even from time to time?
• Do the areas of pain vary slightly or are there other symptoms in the same leg i.e. tightness, heaviness, cramping etc?
• Are the symptoms difficult to pin-point?

If the answer to some or all of these questions is yes then there may well be a single cause and therefore a simple answer!

Up and Running (Sports injury Clinics) are experts in the treatment and management of sports injuries.

Part 2 ITB Syndrome

What is the ITB?

The Ilio-Tibial Band is a thick fibrous tissue (tendon) coming primarily from the Tensor Fascia Latae and Gluteus Medius muscles in the hip and from the hip bone itself (Iliac crest). It inserts into the Tibia just below the knee joint with some fibres attaching to the Patella (knee cap). 4. 6. 7. 8. 9. 13.

(UpMyBlog, 2013)

What is ITB Syndrome?

Ilio-Tibial Band (ITB) Syndrome is a common affliction particularly affecting runners, cyclists and walkers but can affect anyone and is usually felt in the lateral (outside) thigh area between the hip and the knee. 1. 2. 5. 6. 10.

ITB Syndrome affects the lateral epicondyle of the Femur (thigh bone) as in the diagram below. This is due to friction of the ITB as it flicks over the femoral condyle (bony protrusion on the outside of the knee) on each stride of the run or turn of the pedal and causes the bursa (a sac of fluid to dissipate the effects of friction) to become inflamed and swollen. 11. 12.

This friction is thought to be because the ITB is tight and does not allow enough tolerance for it to clear the femoral condyle.

What causes ITB syndrome?

As usual there are conflicting theories about this particular injury just as there are conflicting theories of the causes of so many other sporting injuries. A review of the published literature suggests the following could potentially cause ITB Syndrome:

Training issues 5. 6. 7. 10. 14. 15.

• Overuse – cyclists, runners, walkers
• Running downhill or on banked surfaces too much
• Running too many track workouts in the same direction

Equipment issues 2. 4. 8. 10. 13.

• Worn-out shoes
• Cycling toe-in angle
• Limited “float” of cleats

Muscle imbalance 3. 8. 11. 12.

• Abductor muscles tight/weak/non-firing
• Gluteus Medius tight/weak/non-firing

Biomechanical factors 1. 10. 13. 14.

• High or low foot arches
• Supination/over-pronation of the foot
• Uneven leg length
• Knee Varus (Bow-legged)
• Knee Valgus (Knock-kneed)
• Hip abnormality

What can be done about it?

If we take each of the above factors using their numbers and look more closely at them it may help to determine the likelihood of this as a factor for individuals suffering with ITB syndrome.

1. Overuse is clearly a factor in that, whatever else might be causing the ITB to be tight, if one did not run, cycle or walk excessively then the pain would not present. That being so one of the remedies might be to reduce the activity levels until such time as the cause can be identified. However, thousands of runners, walkers and cyclists cover vast distances without ever suffering ITB syndrome so overuse alone cannot be the only answer.
2. Running down-hill or on banked surfaces. While this activity might increase the symptoms due to the muscle loads on certain muscle groups such as in 7, 8 and 9 above it would take an excessive amount to actually cause this condition in the author’s opinion. Try running on flat terrain if you believe this to be a factor but bear in mind that if you already suffer from ITB syndrome, any running will exacerbate the symptoms.
3. Running bends too often. As in 2 above it would take an inordinate number of laps to cause ITB syndrome. If this were a factor every track athlete would be suffering, however if you believe this to be a factor change where you run for a while.
4. Worn out shoes or wrong shoe type may alter the forces upon landing and could be a causative factor in ITB syndrome. Certainly the way the foot strikes the ground is crucial to the shock forces through the body. Consult the experts at a running store.
5. Cycling toe-In. This position may result in excessive strain on the lateral structures of the leg and has the potential for causing ITB syndrome, particularly with the repetitive nature of the cycling action.
6. Limited “float” of cleats restricts the range of available movement of the feet and is another possible causative factor in ITB syndrome. In both of these cycling specific factors it is best to consult with a cycling specialist shop or similar.
7. Abductor muscles tight/weak/non-firing. The abductor muscles of the leg include the Gluteus Maximus, Medius and Minimus; the Tensor Fascia Latae and other muscles such as the Abductor Longus. If the cause of ITB syndrome is associated with these muscles not firing, being weak or being tight this begs the question why is that so? Tightness, weakness or non-firing are symptoms of something happening elsewhere which in turn cause these conditions. Find the cause and treat it effectively and the muscular symptoms will disappear.
8. Gluteus Medius tight/weak/non-firing has been covered above but the Gluteus Medius, along with the Tensor Fascia Latae, are the two foremost muscle origins of the ITB therefore perhaps more so than the other muscles could affect the ITB. As mentioned above however these are symptoms of a problem elsewhere therefore attempting to strengthen, stretch or somehow fire-up these muscles locally will in all probability fail.
9. High or Low foot arches are postulated to alter the biomechanical action of running gait which in turn create unwanted actions to correct or re-align the biomechanics. The arguments to support this theory have not yet been proven however a specialist in biomechanics is probably the best person for advice if you are of this persuasion.
10. Supination/over-pronation of the foot both come into a similar category to high or low foot arches whereby the foot action significantly alters biomechanics of the running gait. The research however does not support this theory.
11. Uneven leg length will in all probability affect the hip action and could be a causative factor in ITB syndrome. Measuring leg length for discrepancy is relatively easy to do, however be aware that apparent leg length discrepancy can be misleading. It does not necessarily mean that there is a bone length discrepancy or hip angle discrepancy (see hip abnormality below) as muscles can, and often do, cause the pelvis to rotate which in turn alters the apparent leg length. If you believe you may have a leg length discrepancy then go to a Graduate Sports Therapist, Physiotherapist or other appropriate medical professional who should be able to advise.
12. Knee Varus (bow legged) may be a factor in ITB syndrome. Knee Varus can be congenital or acquired. If it is acquired then there are probably other factors which need to be taken into account so seek the advice of a Graduate Sports Therapist or Physiotherapist or other appropriate medical professional.
13. Knee Valgus (knocked Knees) would seem less likely to cause ITB syndrome but like knee varus should be checked by an appropriate medical expert.
14. Hip abnormality. There are various hip conditions both congenital and acquired that may lead to ITB syndrome. Common amongst these are hip dysplasia, femoral neck angle alignment (see diagram below) and Osteoarthritic changes. All of these conditions require appropriate medical advice before continuing with activity.

(Addingrefs, 2009)

Differential diagnosis (What else could it be?) 2. 15.

• Biceps femoris tendinopathy
• Degenerative joint disease
• Lateral collateral ligament sprain
• Lateral meniscal tear
• Myofascial pain
• Patellofemoral stress syndrome
• Popliteal tendinopathy
• Referred pain from lumbar spine
• Stress fracture
• Superior tibiofibular joint sprain

The Author’s view

ITB syndrome has a number of potential causes. If the cause can be found then the treatments will be more effective. Too often therapists of all persuasions treat just the symptoms. By all means treat the symptoms of inflammation and pain but also find out why it is rubbing otherwise it will just return.

Massaging the ITB is one such “treatment” that seems to be both futile and painful. The ITB is a thick, pretty much non-elastic band that comes off muscles in the hip and the hip bone itself. It is probable that the tightness in the muscles from which the ITB comes causes a tension in the ITB, but why are the muscles tight in the first place?

As mentioned in previous articles apart from pathological conditions there are primarily three reasons for muscle tension; overuse; injury to a muscle; or altered signals to the muscles. If it is the latter then the cause may not be obvious and the opinion of an expert should be sought.

Part 3 Osgood-Schlatters Disease

What is Osgood-Schlatters Disease?

Osgood-Schlatters Disease is actually not a disease at all, it is a condition brought about by repetitive muscular action of the Quadriceps muscles. This in turn tugs on the attachment of the Patella Tendon where it inserts into the Tibial Tuberosity – the bony lump at the top of the Tibia (shin bone). 2. 4.

What causes Osgood-Schlatters Disease?

OSD is most often seen in adolescents who are quite sporty. 5. During periods of growth the long bones, of which the Tibia is one, grow predominantly from the growth-plates which are near the ends of bone.

The growth plate is softer than the rest of the bone during growth. The growth-plates for the Tibia are also where the Quadriceps Muscles insert via the Patella Tendon (sometimes called the Patella Ligament) onto the Tibial Tubersity. The constant tugging exerted by the activation of the Quadriceps Muscles avulses (lifts) this attachment off the Tibial Tuberosity.

This causes inflammation and pain on the Tibial Tuberosity and can often be characterised by a tender lump. 1. 3.

(Orthopaedic Surgery, 2013)

What can be done about it?

The condition is not thought to be too serious and often does not require treatment – just rest from activity until the growth-spurt has ended. 5. Reducing the intensity and duration of activity could allow the more committed to manage rehabilitation with periods of rest so that time given to practise is not totally lost. OSD can be quite painful which, in turn, limits the amount of exercise one can do anyway.

Stretches for the Quadriceps Muscles may be useful in re-aligning the healing tendon fibres and stretching muscles and tendons in an effort to limit muscular tension on the Tibial Tuberosity. 4. 6.

The application of ice packs for short-durations of no more than 10 minutes limits swelling especially when the knee is sore or following activity. 2. 3. 4.

Electrotherapy should NOT be used on adolescents or on growth plates and so should never be used on this condition. 5. 6.

The Authors View

The author concurs with most available literature that Osgood-Schlatters is an over use injury affecting mostly adolescents. It is a relatively simple problem to detect with tenderness over the tibial tuberosity and pain on certain activities, most commonly jumping, running and kicking. The problem usually coincides with growth spurts where the growth plate of the tibia has softened and the constant tugging of the quadriceps via the patella tendon avulses the attachment to the tibial tuberosity.

Treatment consists of rest, ice, compression and elevation in the acute phase. A period of either complete rest or minimal activity and gentle stretching of the quadriceps muscles will also help to minimise the tugging.

Part 4 Jumper’s knee

What is it?

Patella tendinopathy, also known as jumper’s knee, is a relatively common condition that causes pain in the anterior (front) aspect of the knee. This pain is usually of a sharp nature and occurs when overloading the extensor mechanism. 2. 9. 12. The extensor mechanism, which includes the quadriceps muscles, the patella and patella tendon, connects the quadriceps muscles to the patella (kneecap) and then on to the tibia (shin) via the patella tendon. 1. 8. 14.

Patella tendinopathy begins as tugging of the patella tendon where it attaches to the inferior pole of the patella that causes tearing or degeneration of the tendon. 3. 5. 10. 13.

(Rehband, 2013)

What causes it?

Jumper’s knee is an overuse injury that results from repetitive overloading of the extensor mechanism of the knee. Micro-tears to the patellar tendon often exceed the body’s ability to heal the area unless the aggravating activity is stopped for a period of time. 2. 8. 9.

Jumper’s knee occurs in many types of athletes but is most common in those participating in sports such as high jump, long jump, netball, basketball, volleyball, or football, all of which require explosive or jumping movements. 6. 7. 10. 12.

Eccentric loading, which is contraction of the muscle while it is lengthening, occurs when landing from a jump or when decelerating. In fact, knee loads of up to 7 times body weight occur in a soccer player during kicking and between 9 and 11 times body weight occurs in netball and volleyball players during landing.

These eccentric loads are perhaps the primary cause of overload in jumper’s knee. 1. 2. 5. 9. 14.

Differential Diagnosis – What else could it be?

There are several knee conditions that have symptoms similar to Jumpers Knee and so it is wise to consult an expert such as a Graduate Sports Therapist or a Physiotherapist who has undertaken extensive sports injuries training. The list of differential diagnosis may include the following: 1. 11. 13.

• Patello-Femoral Pain Syndrome
• Meniscal tears
• Fat pad impingement
• Synovial impingement
• Osgood-Schlatters Disease

How should it be treated?

A good therapist will understand that athletes and sports men and women do not want to stop training; they will want to do something in order to maintain fitness and compete if at all possible.

Jumpers Knee is one condition that must be treated with respect. Jumpers Knee rarely gets better unless there is cessation from training or at least the kind of training that caused the injury in the first place. 4. 9. 12. By all means continue to do forms of exercise, which do not unduly stress the extensor mechanism, but to continue training through the pain is likely to result in serious injury that may require surgical intervention. 1. 2. 5. 10.

Textbooks will often describe Jumpers Knee as an inflammation of the Patella Tendon and may suggest the R.I.C.E. formulae (Rest, Ice, Compression and Elevation) as a treatment however the jury is out on whether or not there is inflammation in tendon injuries. 2. 3. For this reason more recent texts will call these injuries Tendinopathy (a pathological condition) as opposed to some older texts using Tendinitis (‘itis’ means inflammation) however one cannot go too far wrong by using the RICE formulae when dealing with Jumpers Knee in its early stages.

Over time, and if there are signs of improvement in the condition, gentle stretching of the quadriceps muscles will help to re-align the new collagen fibres that are repairing the tendon into a more linear configuration. Therefore giving the tendon greater tensile strength when it is repaired. Gentle strengthening exercises may also be introduced to stress the new fibres and to begin muscle strengthening of the quadriceps. Care must be taken at this stage not to re-injure the tendon by doing too much too soon. 7. 9. 11. 13. 14.

Again, rehabilitation should be gradual until such time as return to sport is possible. The guidance of a Graduate Sports Therapist would be useful throughout this injury but especially at this stage as sport specific training will be needed to ensure the injury is able once again to withstand sport specific training and competition.

The Authors View

This injury is one that Up and Running Sports Injury Clinics has encountered on many occasions hence the caution in the treatment regime recommended above.

Tendons heal more slowly than muscles due to the poor vascularisation (blood flow) through tendons. Various treatment modalities have been experimented with to improve the rate of repair including ultrasound, interferential, NSAIDS (non-steroidal anti-inflammatory drugs), corticosteroid injections, shock wave therapy, sclerotherapy, nitric oxide patches, surgery, growth factors, and stem cell treatment.

Since there appears to be little or no inflammation in tendon injuries many of the treatments above have proven not to be effective. The body has the ability to heal itself most of the time so the key to effective treatment of Jumpers Knee is to assist the body to heal itself gradually.

Knowing HOW the body heals and assisting in that healing process seems to be the way forward.

Part 5 Knee Ligament Injuries

What are ligaments and what is their function?

As mentioned in the earlier articles the knee joint is a very complex joint and the following is a simplistic guide to the structure and function of ligaments. Stability of any joint relies on several factors. The shape of the bones at the joint can contribute to stabilisation such as the depth of the hollows and the height of the Inter-Condular Notch of the Tibia where the Femur articulates in the knee. Then there are passive or static stabilisers called ligaments and dynamic stabilisers namely the muscles. 3. 4. 8. 

Ligaments are known as passive or static stabilisers because unlike muscles they cannot contract. 1. 10.

Ligaments act across joints attaching from bone to bone. The knee has four major ligaments whose job it is to stabilise the joint. These four ligaments are the Medial Collateral Ligament, the Lateral Collateral Ligament, the Anterior Cruciate Ligament and the Posterior Cruciate Ligament. 1. 6. 9.

Yale Medical Group, 2010

The Collateral Ligaments helps prevent unwanted lateral (sideways) movement whilst the Anterior Cruciate Ligament prevents the Femur (thigh bone) slipping backwards on the Tibia and the Posterior Cruciate Ligament prevents the Femur slipping forwards on the Tibia. 2. 5. 7. If any of these ligaments are completely ruptured then there is a high risk of the knee being unstable.

Ligaments have high tensile strength being made from collagen, a strong structure made of protein fibres. Ligament tears are graded 1, 2 and 3 for severity, 3 being a complete or almost complete rupture. Amazingly complete ruptures are often less painful than partial tears due to the nerve ends being severed as opposed to being damaged. 3. 4. 9.

What causes ligaments to tear?

Ligaments can become damaged when various forces, that are too great for them to withstand, are applied to the knee. These forces are generated either intrinsically, such as when landing from a jump but without the control needed to cope, or extrinsically such as when a player is tackled. 6. 7. 10.

The fibres are stretched to breaking point and either some or all of the fibres tear. A sprain is when some fibres are torn; a rupture is when all fibres are torn.

If you have experienced an incident where a large force may have been applied to the knee and you are now suffering from pain in the knee, instability of the knee and swelling, it may be worthwhile to see a physiotherapist or GP for advice and a diagnosis. 2. 3. 5. 

The knee joint is surrounded by a protective joint capsule called the Synovia. This synovial membrane produces synovial fluid, which helps to lubricate and reduce friction within the knee joint. 7. 9. 10.

What can be done about ligament tears?

Ligaments are capable of healing as they have a blood supply but they are not as rich in blood supply as muscles therefore it takes longer for the healing to take place. 1. 4. 6.

As with any injury however in the early stages of injury there is a need to reduce blood flow in order to minimise blood loss and tissue oedema (swelling).

Rest, Ice, Compression and Elevation (R.I.C.E.) is a pretty good standard treatment but, be very careful with ice application. There are two potential problems with ice application.

The first is an ice burn. Do not apply ice directly on to the skin. Ensure there is a barrier between the skin and the ice and try to use ice that is melting slightly. Secondly, ice application causes vaso-constriction, (closing of the blood vessels) in the first instance but after approximately ten minutes the body’s reaction is to vaso-dilate (open the blood vessels). This means greater blood flow and therefore potentially more swelling. 8. 10.

It is very important that you protect your knee from further damage as it may become quite unstable with ligament tears. Unlike injured muscles, ligaments should not be stretched during the rehabilitation stages. Rest and gentle mobilisations in the correct anatomical plane for that joint should be performed as pain allows. 3. 5. 9.

Ligaments can take up to several weeks to repair. It is advised develop muscle strength around the injured ligament to help to stabilise the joint using the muscles as dynamic stabilisers. 2. 3. 8.

Where ligaments have completely ruptured it is likely that surgery may be required. 7. 8.

Authors View

If you think that you may have suffered ligament damage it is recommended that you see a health professional. Diagnosis can be relatively simple with a few tests carried out by the medical practitioner.

For more complex cases, diagnosis may require MRI or ultrasound scans. Input from a physiotherapist or sports therapist can be beneficial as treatment of ligament injuries can be tricky.

Finding the right balance between rest, gentle stretching and strengthening is necessary for optimum healing, stability of the injured knee and prevention of subsequent injury.

Part 6 Patella Dislocations

What is a Patella Dislocation?

Patella (kneecap) dislocations are quite common and can be very disconcerting to the sufferer. The Patella sits in a groove (Trochlea) in the Femur and usually glides up and down in this Femoral Trochlea during movement.

Dislocation occurs when the Patella is forced out of this groove, usually laterally, causing pain, swelling and temporary deformity of the knee joint. Quite often the Patella relocates spontaneously when the patient moves the leg but if this does not happen then it must be relocated by a suitably qualified medical professional. 1. 4. 8. 9.

Perhaps even more common is a Patella Subluxation, a partial dislocation that relocates before the point of full dislocation. There is still pain and swelling because of the bone on bone friction and in either a subluxation or dislocation the patient will suffer apprehension and instability. 3. 5. 7.

(UMMC, 2008)

What causes Patella Dislocations?

There are a number of predisposing factors that may lead to Patella Dislocation. The shape of the Trochlea, the size and shape of the Patella, inherent joint laxity either ligamentous or muscular, stage of maturation, muscle imbalance and poor proprioception. 2. 6.

Patella dislocations occur more often in younger athletes due perhaps to some of the aforementioned factors but also perhaps because of the vigorous activities undertaken. Dislocations occur either extrinsically (direct contact with an external force) or intrinsically (from forces generated within) usually when landing with a twist or from a twist such as in gymnastics, rugby or football. 2. 11. 12.

What are the signs and symptoms?

A Patella dislocation that does not relocate spontaneously is obvious. The Patella sits to one side of the knee; usually the lateral side, and the patient will be unable to move the knee at first.

There will be pain and swelling follows fairly quickly afterwards. The sufferer will have felt a “giving way” of the knee at the point of impact or landing and apprehension will limit movement.

Usually Patella dislocations incur other injuries such as Patella Ligament damage; bone-on-bone friction, which can cause fragments of bone to break off; Capsular tears and other soft tissue damage. 5. 9. 11.

Patella subluxations have similar symptoms as dislocations except that the Patella relocates prior to full dislocation. Apart therefore from the deformity of a dislocation the symptoms are pretty much the same. 1. 3. 12.

(Fight times, 2003)

What else could it be?

There are other conditions that can mimic a subluxation such as a Meniscus tear; Jumpers knee; Patello-Femoral Pain Syndrome; bone lesions and a host of other conditions. 4. 7. 9. 12. The deformity of a Patella Dislocation however is pretty obvious.

What can be done about it?

In the case of a Patella Dislocation it is important to go to A&E so that the Patella can be safely relocated but also to check for other injuries such as bone damage. Quite often the dislocation hides the fact that other injuries have occurred.

If the Patella has spontaneously relocated then it may still be wise to have the knee checked at A&E for similar reasons as above. Quite often however the sufferer has not fully realised what has happened and often goes home to nurse an increasingly swollen knee.

As with most injuries control of swelling is important in order to begin the rehabilitation process as soon as possible. Therefore the PRICE regime (Protect; Rest; Ice; Compression: Elevation) should be followed. 6. 8.

Be careful with the application of ice regime as too long an application of ice can increase swelling! Similarly, always place a barrier between the ice and the patients skin and try to use melting ice (not straight from the freezer) to prevent ice burns. 5. 7.

Static quadriceps exercises should be performed as soon as the patient feels able to as this will help remove swelling and begin restoring muscle function. Movement and strength will gradually be restored over time. 4. 9. 11. 12.

Giving a time frame for these processes is difficult due to the vastly differing severity of this condition.

In order to rehabilitate faster and to minimise the chances of re-injury it is advisable to seek the services of a Graduate Sports Therapist or a Physiotherapist who has undergone extensive training in sports injury management.

The Authors View

Patella dislocations can be very traumatic as they almost totally debilitate the athlete for a period of time. The pain and swelling take time to subside but perhaps the most debilitating aspect is the apprehension at the thought of it going again. Careful rehabilitation with graded return to activity is vital not only for the injury to repair but to ultimately nurse the athlete back to competition level from a psychological perspective.

A Graduate Sports Therapist or Physiotherapist with appropriate sports specific qualifications will be able to help in this rehabilitation process.

Part 7 Chondral (Bone) defects of the knee

What is a Chondral Defect?

The articulating surfaces of the knee joint have a hard, shiny coating called the Articular Cartilage. This Articular Cartilage is incredibly durable and prevents much wear and tear of the bones as the surfaces are repeatedly rubbed together during everyday actions such as walking, running, squatting etc. Damage to the articular cartilage is called a Chondral Defect. 3. 6. 8.

What causes these defects?

Damage can occur over time with wear and tear or may be as a result of a sudden trauma. 2. 4. 6. In the case of wear and tear this degeneration is called Osteoarthritis. 10. 14. Painful osteoarthritis develops when this smooth, gliding surface on the end of the bone has lost its coating, deformity develops, and bone rubs on bone. This can result in very painful knees. This kind of damage tends to be more common in later life but, for many reasons may appear in the relatively young. 7. 8. 9. 12.

More often, there is no clear history of a single injury. The patient’s condition may, in fact, result from a series of minor injuries that have occurred over time. Contributing factors to this wear and tear could be mal-tracking Patellae (see Patello-Femoral Pain Syndrome); repetitive movements such as in long-distance runners; excessive kneeling; squatting using heavy weights and similar excessive activities. 9. 10. 11.

Sudden trauma is also a common cause of a Chondral Defect especially in certain sports and activities. A chondral injury may occur as a result of a pivot or twist on a bent knee, similar to the motion that can cause a meniscus tear. Damage may also occur as a result of a direct blow to the knee such as in a fall or collision.

Chondral injuries may accompany an injury to a ligament, such as the anterior cruciate ligament. Small pieces of the articular cartilage can actually break off and float around in the knee as loose bodies, causing locking, catching, and/or swelling. 1. 5. 13.

What else could it be (Differential diagnosis)?

As previously mentioned, the knee joint is extremely complex and diagnosis of injury is quite difficult. The more common signs of a Chondral Defect are also common signs of a number of other conditions:

• Pain – can be caused by many different factors in the knee, too many to mention here;
• Swelling – again, the result of several knee conditions;
• Locking – usually associated with Meniscal tears but may be the result of a fragment of articular cartilage floating around;
• Aching – may be as a result of a neuromuscular problem.

Given the caveat above there are many other injuries that could give similar symptoms to a Chondral Defect but working through each possibility is time consuming and often inconclusive. 5. 9.  

A Graduate Sports Therapist or Physiotherapist with appropriate training may be able to provide a more accurate assessment of other possible injuries however the only way to diagnose a Chondral Defect is by some form of imaging such as an X-Ray, an MRI or ultrasound scan, or by an arthroscopy (Key-hole surgery whereby a mini camera is inserted into the knee joint). 7. 12.

What can be done about bone defects?

This depends on exactly what has caused the Chondral Defect and how severe the defect is.

If there is a large surface area of defect the likelihood is that rest alone may not be enough and surgery is often prescribed. 2. 3. 4. 6. 8. Large, full thickness defects rarely repair spontaneously. There are several methods of surgical repair for large Chondral Defects these include abrasion, drilling, autografts, allografts, and cell transplantation. 1. 2. 3. 4. If you are unfortunate enough to suffer from this injury the consultant will usually discuss the preferred method.

Where the injury is not full thickness or of a small surface area it may be possible to rehabilitate the knee conservatively. 15. In the case of Patello-Femoral type wear re-tracking is required either by eliminating the cause of the mal-tracking (preferable) or by taping the knee in such a way as to prevent mal-tracking whilst undertaking activity. 1. 3. 11. 15.

In other cases, and also with Patello-Femoral Pain Syndrome, rest from activity may be required until such time as the symptoms resolve.

The Authors View

Obtaining the correct diagnosis is obviously the key to appropriate treatment. The best methods for determining Chondral Defects require imaging or surgery however, as previously mentioned there are many other injuries which produce similar symptoms to Chondral Defects.

These other injuries require the expertise of someone with appropriate training, such as a Graduate Sports Therapist or a Physiotherapist with sports injury training, to more accurately ascertain the cause.

Final Thoughts on Knee Pain and Injury Prevention

Knee pain can stem from a wide range of causes from overuse and biomechanical imbalances to traumatic injuries. Understanding the underlying condition is essential for effective treatment and long-term recovery.

This guide highlights the importance of proper diagnosis, gradual rehabilitation, and professional assessment. If you experience persistent or severe knee pain, consult a qualified healthcare professional to identify the root cause and receive appropriate care tailored to your individual needs.

In the event you are suffering from knee pain, we always advise you seek a medical professional either from a qualified physiotherapist or you GP. In the event you have minor issues related to running or walking you can visit one of our stores and talk to one of our staff members or make use of our Biomechanical assessment and Gait analysis.