Brian Schiff’s Blog

In many cases, my clients are unable to perform traditional strengthening exercises for the lower body due to anterior knee pain or weakness. Beyond loading, using the time under tension principle is a great way to add strength for those who cannot squat, lunge, etc. Below are two great videos of isometric ‘go-to’ exercises that will help improve strength and functional capacity in those who are otherwise limited in their workouts.

I hope you can use these exercises or some variation of them to increase strength and overcome injury and dysfunction.

It is common knowledge in the medical community that treating patellofemoral joint pain (PFJP) is one of the most frustrating and difficult tasks to complete as there appears to be no standard way to do so.  While clinicians strive to find the right recipe or protocol (I don’t believe there is just one by the way), researchers press on to find more clues.

A new article released in the April 2011 Journal of Orthopaedic & Sports Physical Therapy seeks to bring clarification to a particular exercise pattern commonly used in rehab circles.  The three exercises they looked at were:

• Forward step-up
• Lateral step-up
• Forward step-down

In the study, the authors looked at 20 healthy subjects (ages 18-35 and 10 males/females) performing the separate tasks with motion analysis, EMG and a force plate.  The goal was to quantify patellofemoral joint reaction force (PFJRF) and patellofemoral joint stress (PFJS) during all three exercises with a step height that allowed a standard knee flexion angle of 45 degrees specific to each participant.

Key point:  Previous research has been done to indicate that in a closed chain setting, knee flexion beyond 60 degrees leads to increased patellofemoral joint compression and this may be contraindicated for those with PFJ pain or chondromalacia.  Also keep in mind that most people with PFJ complain of more pain descending stairs than ascending stairs.

In the study, the participants performed 3 trials of 5 repetitions of each exercise at a cadence of 1/0/1 paced with a metronome.  The order of testing was randomized for each person.  The authors used a biomechanical model to quantify PFJRF and PFJS consisting of knee flexion angle, adjusted knee extensor moment, PFJ contact area, quadriceps effective lever arm, and the relationship b/w quadriceps force and PFJRF.

Now on to the results……

Continue reading…

Anterior knee pain, aka chondromalacia, patellofemoral pain (PFP) and patellofemoral pain syndrome (PFPS), may be the most difficult condition to remedy in the clinic or gym.  There is always debate and speculation when it comes to taping, bracing, orthotics and exercise.

In the latest edition of the JOSPT, there was a summary from the findings presented at an international retreat held in the spring of 2009 in Maryland.  The publication covered the keynote addresses and podium presentations.

Before I give you the quick and dirty details, I want to emphasize a key point that was made and one I happen to wholeheartedly agree with.  It is this:

When assessing and evaluating those with PFPS, it is important to recognize that these patients/clients do not necessarily fit under one broad classification system.  The anterior knee pain issue is multi-factorial and not every person has the same issues or abnormalities.  As such, the exercise prescription most likely will need to be tweaked accordingly for best results.

Okay, now on to the highlights that may impact your training/rehab.  Some researchers from Belgium have been conducting prospective studies looking at intrinsic risk factors for developing PFPS.  They looked at physical education students and novice runners.  Major findings are included below:

Study #1

There were 4 variables identified as risk factors:

• Decreased flexibility of the quadriceps
• Decreased explosive strength of the quadriceps
• Altered neuromuscular coordination b/w the vastus lateralis (VL) and vastus medialis oblique (VMO)
• Hypermobility of the patella

Study #2

• More laterally directed plantar pressure distribution at initial (foot) contact during walking and more laterally directed rollover are risk factors for developing PFPS

Study #3

• Unable to link hip muscle strength (or weakness) to increasing risk for PFPS
• No apparent correlation with frontal plane motion of the knee and hip strength (so hip weakness will not automatically cause knee pain)

Finally, what does this mean for therapists and fitness pros?  It means…….

1. They should address the 4 intrinsic risk factors by stretching and strengthening the quads, with a particular emphasis on balancing the VMO strength in relation to VL strength.  This is not new information.  Spending time on closed chain terminal range strengthening is important. 
2. Second, keenly observing a dynamic disturbance in foot alignment at contact is important  for predicting PFPS and will undoubtedly impact dynamic training protocols for the entire kinetic chain. 
3. Lastly, continue to strengthen the hip even though the final study revealed no apparent link.  However, perhaps focus more on this when there is a definitive weakness side-to-side that has been identified.  So, don’t fall back on the weak gluteus medius by default; rather use dysfunction as a driver for exercise inclusion.

PFPS is and will continue to be a difficult problem to treat and remedy with exercise.  Further research is needed to determine and evaluate more specific gender differences, kinetic chain links, the efficacy of taping/bracing, and the most effective classification and treatment algorithms for those of us in the trenches.  In the meantime, listen to the body and use the best available science and information to move forward with your training. 

Reference: JOSPT March 2010