PATELLOFEMORAL PAIN: All you need to know! (part 2)
RISK FACTORS: MULTIMODAL ETIOLOGY
As if the above factors were not enough, we got some more factors which are considered to be risk factors in contributing to the onset of this condition. These are structural causes which are divided into distal, local and proximal deficits. These include foot posture while running (ref) , reduced Quad strength (ref), delayed VMO activation (ref), weakness in eccentric hip abduction and hip external rotation (ref). It is seen that someone with PFP will show a combination of these local, proximal and distal factors making looking for the cause of pain that much more complex.
BIOMEDICAL OR BIOPSYCHOSOCIAL APPROACH ?
There seems to be no consensus at the moment on what causes PFP. Most likely, it is a combination of many factors, both structural and psychosocial. It has been shown that PFP seems to get better without any change in the alignment of structures which were initially thought as misaligned and evidently the cause of pain. (ref) The concept of central sensitization and implications of psychological factors like kinesiophobia have already been touched upon.
THE EXPERIENCE OF LIVING WITH PFP
In our quest of looking for the cause of pain, we tend to forget and ignore what it means for the patient to be living with pain and how it impacts their beliefs and lives. This brilliant study (ref) touched upon the experience of living with PFP and gave us an insight into the lived experience of individuals with PFP. Previous literature has focused on pain and biomechanics, rather than the individual experience and attached meanings. There were five major themes that came up:
- Impact on self:
"I struggle at work, bending down to get to the bottom shelf and getting back up, I literally have to hold onto the table to pull myself up. I can’t do it off just my knees."
- Uncertainty and confusion:
"The work physio guy said to me that he thinks that my heels have maybe gone in which has then pulled my kneecap out of alignment."
- Exercise and Activity beliefs:
"With me it’s always been, if something hurt it be- cause your body’s telling you if you do that you’re go- ing to cause more injury. You’ll make things worse."
- Behavioral coping strategies:
"I try, obviously, sit down as much as I can"
- Expectations of the future:
"I would presume manipulation of muscles groups, joints and tendons."
ASSESSMENT
As always, careful questioning and receiving a detailed subjective history forms the roadmap of objective testing. Open -ended questions and reflective listening forms the backbone of assessment of PFP. The goal of assessment is to consider the differential keeping in mind the multimodal etiology of PFP and understanding the psychosocial factors impacting the condition. Patients are asked about activities like walking (uphill, downhill, stairs) and whether the pain comes on after sitting for prolonged periods of time with the knee flexed. (Moviegoer sign). Probably the most important thing to note down is the quantification of training loads including the intensity, frequency and duration of training. Pain history and presentation gives us clues about the differentials and response of pain during knee flexion activities should be noted along with the type of footwear. We should keep in mind the lifestyle factors and psychosocial factors which, as we already know by now, are imperative in the management of PFP.
CREPITUS
PFP is often associated with crepitus in the knee which can lead to fear avoidance and patients believing that their knee is wearing away. This study (ref) found that kinesiophobia, catastrophism, knee stiffness, strength and physical function are all impaired in women with PFP, regardless of crepitus. Crepitus has been shown to not affect quality of life and function with knee OA (ref). Therefore, the topic of crepitus associated with knee movement should be tackled with sensitivity and it should be observed as to what the crepitus means to the patient rather than blatantly disregarding that crepitus is normal and does not mean structural damage. Be careful before generalizing something you are not fully sure of!
