The patient rated her pain according to a verbal numeric rating
scale (0 representing the absence of pain and 10 representing the
worst pain imaginable). Over a 24-h period, pain ranged from 0
out of 10 to 6 out of 10 and was intermittent in nature and
associated with certain exacerbating activities. No prior episodes
of knee pain were reported, and her past medical history was
negative for any co-morbidities. The patient, a full time student,
worked a few hours a week at a desk job and had limited her
preferred exercise, walking, due to her symptoms.
Examination
Lower extremity active range of motion was normal. Strength
measurements via manual muscle testing described by Kendall
et al (2005) demonstrated lower abdominal strength 4/5; upper
abdominals 5/5; illiopsoas, hip lateral rotation and gluteus
maximus 4/5 bilaterally; quadriceps 5/5; and hamstrings 5/5.
Palpation revealed tenderness of the lateral patellar retinaculum.
The apprehension test was negative, but hypermobility of the
patella was subjectively noted with medial and lateral glides.
Craig’s test for femoral antiversion/retroversion revealed no
significant structural faults bilaterally testing at 10–15 of femoral
medial rotation. No swelling or abnormal muscle bulk was
evident with visual inspection. Testing of intra and extra-articular
ligaments of the knee was negative for laxity. To assess lower
extremity movement patterns with functional movements, a
digital video camera was aligned directly in front of the patient’s
midline (perpendicular to the frontal plane), 3m anterior to the
patient at the height of the patient’s knees. The 2D method
previously used to calculate medial collapse (Chmielewski et al,
2007; Hollman et al, 2009; Willson and Davis, 2008) was
simplified to a classification of two categories: (1) medial
collapse, defined as the midpoint of the patella vertically
positioned medial to the second toe and (2) no collapse, defined
as the midpoint of the patella vertically positioned in line with or
lateral to the second toe. Test maneuvers were recorded on video
tape and with still imagery as demonstrated in Figures 1–4.