Patellofemoral pain

In the lesson on Differential Diagnosis we learned of the many conditions in which pain around the knee cap resulted from conditions altering the mechanics of the knee.

Many of these conditions will respond to a programme of physical therapy, and surgery can frequently be avoided altogether. When I think of the extensor mechanism, I think of a marionette (puppet with strings). Pull a string and something moves at a distance from the string. All the bits are affected by their connection to all the other bits. Posture follows the same principle - shorten the hamstrings, and the back sways, etcetera. Much of the work of the physiotherapist is involved in rebalancing the muscle systems and improving posture.

In this lesson we will discuss some of the principles of such 'conservative' (i.e. non-surgical) therapy -

• mechanical support and improvement of posture
• preventing overuse
• releasing tight structures
• improving muscle balance
• relieving local inflammation
• painkillers
• artificial lubrication
• diet and nutritional supplements

We will also look at the current options for the management of complex regional pain syndrome.

Mechanical support and improvement of posture

General Posture and Gait Improvement

'Gait analysis' is now a speciality within orthopaedics. Poor gait and posture are contributors to knee pain and musculoskeltal and gait training are fundamental to knee rehabilitation.

Foot Orthotics

In patients where excessive foot pronation is contributing to pain around the knee cap, shoe inserts ('orthotics') may make a significant difference.

It is preferable to consult an orthotist who can make a proper assessment and prescribe the most appropriate orthotic.

Patellar Brace

Patients with unstable patellae may benefit from the use of a patellar brace (eg Palumbo brace), which will stabilize the patella while an exercise regime helps to build the quads and hams.

Tendon Straps

Tendon straps, such as the Cho-Pat strap, are useful in patellar tendonitis to move the end point of the tendon away from the affected area.

The Cho-Pat can be likened to a capo on a guitar. You squeeze one area to take tension off another. Cho-Pat have a similar strap for the ilio-tibial band.

Stretches

You need to warm up prior to stretching. Take a walk, jog on the spot, even take a hot bath if you cannot manage a physical warm-up. Stretches need to be maintained for a good twenty seconds, and repeated a couple of times. A daily routine will optimize success.

The hamstrings muscles are the bane of sportsmen. Stretching the hamstrings needs to be an ongoing exercise, as the hamstrings have 'poor memory' and easily tighten up again.

Tight quadriceps contribute to pain around the knee cap as we have learned, and especially the rectus femoris component because it crosses both the hip and the knee. Although this article relates to martial arts sportsmen, the principles apply here, and is an interesting read.

Preventing Overuse

Patients often find it very hard to accept advice to stop or modify an occupational or sporting activity which causes pain in the knee. It is the very person who is conscientious with their occupation or sport who gets 'overuse' symptoms in the first place. Try telling a young enthusiastic footballer with Osgood Schlatter's condition to take a rest from sport, and you will generally meet with fierce resistance. But it can be a simple and effective measure.

These simple steps are too often forgotten! -

• change the activity, or
• reduce the activity, or
• stop the activity

Releasing tight structures on the lateral side

Patellar mobilisation

A routine of 'deep friction massage' can release a tight lateral retinaculum. The thumbs are used in small circular motions, applying moderate force.

Patellar taping has become a routine tool in the physiotherapist's armamentarium. It's value seems to lie in holding the patella in a better position while hams and quads exercises, stretches and deep friction massage are implemented to build a better support around the patella.

[Reprinted with permission, The Adult Knee, Chapters 59-60, Lippincott Williams & Wilkins, 2003.]

Trigger Point Massage

A technique of deep 'stripping' massage may relieve pain around the kneecap caused by tender muscle knots in the quads.

These 'myofascial trigger points' cause referred pain, often some distance from where the pain is experienced (ref). In the knee they are often related to overuse or previous surgery.

Ultrasound or local injection with steroid may also be effective.

Improving Muscle Balance

It is important to develop and maintain a good quads:hams ratio.

Rehabilitation regimes often tend to favour the quads over the hams.

However, tight and weak hams not only contribute to knee pain, but an imbalance in the ratio of strength of the quads and hams can render the knee prone to real injury.

Normal quads:hams ratio is generally accepted as 0.6. Accurate measurements can be obtained with an isokinetic machine, e.g. Cybex.

Quads Strengthening

A graded series of quads exercises to build quads strength may include -

• quads sets
• short arc extensions
• step-ups
• static bike
• leg presses

Progressing to -

• step-ups - graded exercises steping up and down onto a firm surface.
• short arc extensions
• progressing to the static bike.
• progressing to leg presses on a 'multi-gym' under supervision

Hams Strengthening

Hamstrings strength can be built up with graded leg curls -

• leg curls
• resisted leg curls

Relieving local inflammation

RICE regimes after exercise

Of value when exercise triggers local inflammation, this routine consists of -

• rest,
• ice
• compression
• elevation

Non-steroidal anti-inflammatories

The recent bad press of Celebrex and then Vioxx has turned the 'anti-inflammatory' world upside down. When the dust settles (and the lawyers, too) use of this group of drugs will probably be more tightly monitored.

Steroid injections into joint or tendon

Steroid injections into joints and tendons are completely unrelated to the steroids that are currently the talk of the news.

Steroids represent a large class of medications in the same way that the term 'aircraft' refers to jets as well as helicopters and gliders. The steroids that build up muscle mass are anabolic steroids that come with a host of dangerous side effects. Joint and tendon steroids are safe anti-inflammatory medications that quiet down tissue irritation and relieve pain.

Steroid shots are injected into a specific area of inflammation to treat severe knee problems, including arthritis, tendonitis, bursitis and synovitis.

Electrical Therapy

The physiotherapist has a number of electro-therapy tools for reducing local inflammation. These include -

• ultrasound
• interferential
• faradism

Anti-inflammatories

By taking anti-inflammatory medication such as Celebrex, Naproxen, Ibuprofen, or Diclofenac for knee arthritis, a patient manages to live with the pain.

In the past, doctors could monitor a NSAID patient's kidneys, liver and bone marrow with a simple set of blood tests. But there is no test for 'increased risk of heart attack and stroke!' Unfortunately, many knee and hip pain sufferers are unaware of the dangers of the prolonged use of anti-inflammatory medicines - and why? Quite often, it is because they have not been educated by their medical advisors.

Painkillers

Painkillers (analgesics) are not the same class of drug as the anti-inflammatories already mentioned. They work on totally different chemical pathways.

The two main groups are the ordinary painkillers, such as paracetamol, and those which are opioid derivatives and potentially addictive.

Acupuncture

Acupuncture is effective for pain relief and healing in many knee problems, but is only just becoming accepted into western orthopaedic practices.

Acupuncture seems to work via stimulating nerves to release substances which can reduce pain.

TENS

TENS stands for 'transcutaneous electrical nerve stimulation', that is nerve stimulation through the skin.

A TENS unit is a small battery-powered box which you can strap onto your belt. This connects via wires to small electrode patches placed on the painful area. The box emits small electrical impulses which travel through the skin to the underlying nerve fibres, blocking pain pathways to the brain.

Artificial lubricants -Synvisc

Synvisc is an 'lubricant' injected into the joint cavity in cases of arthritis - both tibio-femoral and patello-femoral. It is a synthetic version of what a natural knee makes.

It has been shown to be generally well tolerated - but varies in its efficacy, with some patients finding good benefit while others do not. Usually two or three injections are given, a week apart.

Diet & nutritional supplements

I have to say that there is no one particular diet which has had dramatic effect with my own patients. If I could say there was it would be great. But some people swear by their own diet and I think one or two recommended arthritis diets are worth trying. What works for one person may not work for another, and vice versa.

Weight becomes a vicious cycle when it comes to knees. The more weight you carry, generally the less you exercise.

Arthritis diets

There are many diets proposed for reducing joint pain. Most include -

• things to avoid - coffee, alcohol, wheat, red meat
• things to add - fish products with omega-3 fatty acids (eg cod liver oil), apple cider vinegar, honey

Chondroitin sulfate & glucosamine

These two nutritional supplements are now fairly routinely prescribed by doctors when joint cartilage is under stress.

Glucosamine stimulates the production of new cartilage cells, while chondroitin sulfate prevents enzymatic destruction. They are synergistic - their combined effect is greater than if used individually.

Both are obtained from animal sources and are available without prescription. As they are considered dietary substances, their production is not regulated by the FDA, and quality can vary widely.

So, how long does one place a patient on a physical therapy program before proposing surgery?

There is no definitive answer to this question.

In my opinion, the severity of the problem plays a role. For example, some patients may have no more than mild tilt of their patella that is easily reducible (i.e. the examiner can easily lift the lateral border of the patella to make the patella horizontal). In others, the patella is severely tilted and subluxed ('hanging off the lateral condyle') and cannot be manually corrected. In the former case I would expect a non-operative regimen to be successful. In the latter, I might, in very select cases, bypass physical therapy and propose surgery.

The duration of symptoms and prior treatments also have to be considered. A patient with one week of pain following an initiation to in-line skating and someone with long-standing symptoms who has already been through many treatment regimens will be seen in a very different light. Each case must be individualized.

Note:

The management of knee pain must be holistic. All of the measures we have discussed in this lesson need to be considered. Simply reaching for a prescription pad will be doing the patient a major disfavour.