The patient for this case report was a 56 year-old Caucasian woman with bilateral knee pain. Informed consent was obtained and the rights of the patient were protected. She reported a height of 166.37 cm and a weight of 106.14 kg. Her medical history was significant for osteoporosis, osteoarthritis, and multiple hernia operations. Medications used by the patient included Advil for pain (800 mg, twice per day), Calcium (1200 mg per day), Aspirin (81 mg per day), Nexium (20 mg per day), and vitamin D. Although she complained of shortness of breath with activity, there were no other signs suggesting that the patient would be inappropriate for physical therapy or would require referral back to her physician.
The physician provided a referral for physical therapy to evaluate and treat the medical diagnosis of bilateral knee pain. Per subjective report, the patient confirmed the presence of bilateral knee pain (left greater than right) with a duration of 5-6 years. The patient noted that the initial onset of her symptoms was insidious and that the pain, described as a diffuse aching pain, was located in the anterior aspect of both knees.
Prior to the most recent visit to her physician, and subsequent follow-up with physical therapy, the patient reported a significant increase in pain that she was trying to manage with over-the-counter pain medication. The patient noted that the pain had increased to a point that she could not stand from a sitting position without assistance and had difficulty walking and climbing stairs. Given the severity of the pain, the physician administered a Cortisone injection into both knees one week prior to beginning physical therapy. No specifics were provided regarding the dosage or the location of the injections. According to the patient, the injections relieved most of her pain and improved her function, but she was still taking multiple doses of Advil per day to manage her symptoms. At the time of the initial physical therapy evaluation, the patient reported 2/10 achy pain in the anterior aspect of both knees that worsened with sit to stand and stair climbing.
Prior to the examination, the patient completed the Activities of Daily Living Scale of the Knee Outcome Survey (KOS), a reliable and valid outcome measure of knee pain and function for a variety of diagnoses, including patellofemoral pain. Scores on the KOS range from 0-100 (Standard Error of Measurement and Minimum Detectable Change (MDC67), 5.15) with 0 representing a complete loss of function and 100 representing no loss of function with complete absence of symptoms. When the patient initially completed this form, she obtained a score of 50, suggesting a 50% loss of function. On a separate subjective question that has not been fully validated in the literature, the patient rated her current level of function during daily activities as 30 out of 100, with 100 being the level of function prior to pain or injury. Thus, despite the reported success of the injections, the patient was still documenting significant functional limitation as a result of her knee pain.
According to the patient, the anterior knee pain was still limiting her ability to perform work, household, and recreational activities. The patient was a registered nurse who worked in a physician's clinic. Her job required both desk work and patient care. Therefore, the patient needed to transition from sitting to standing multiple times per day. Additionally, the patient lived in a multi-story home. Thus, the patient had to ascend and descend the stairs several times per day. Both of these activities seemed to contribute to the persistence of her anterior knee pain. Therefore, the patient felt limited in the amount of exercise that she could perform to lose weight and maintain optimal health.
Ultimately, the patient's goals for physical therapy were to maintain or to improve upon the progress achieved from the injections, to decrease her need for pain relieving medication, to build strength and endurance in her lower extremities, and to improve her tolerance for walking, particularly for fitness. The patient was motivated to participate in physical therapy in order to optimize her tolerance of functional activities and to improve her overall health.
Following the subjective history, an objective examination was performed in order to identify specific movement and postural factors that might be contributing to the patient's pain and to quantify measures of muscle performance, range of motion, and alignment (table 1). Visual observation was first used to determine postural alignment in standing. The patient was noted to have bilateral hip adduction with medial rotation of the femurs. In addition, the patient stood with her knees slightly flexed. Inspection of her patellar alignment suggested that her patella was superiorly displaced (figure 1).
Therefore, a more quantitative assessment of her patella alignment was performed based on the Insall-Salvati (IS) ratio,which compares the length of the patellar tendon (TL) to the height of the patella (PL).. proposed that the ratio between patellar tendon length and patella height should normally be one and that two standard deviations (SD) above or below the mean should be considered abnormal. Thus, patients that have a TL/PL ratio of 1.2 or greater (1 + 2 SD) are characterized as having PA. To screen the current patient for PA , the length of the patella tendon was measured using the inferior pole of the patella and the tibial tubercle as landmarks. The height of the patella was measured using the superior margin and the inferior pole of the patella as landmarks. The values were then compared to determine the IS ratio (figure 2).
However, because clinical measures for patella alta have been deemed unreliable, the clinical measurements taken were confirmed with more specific measurements of the lateral radiograph (figure 2) that were provided by the referring physician. To assess for PA on the lateral radiograph provided, the length of the patella tendon was compared to the diagonal height of the patella. While the landmarks used to assess patellar tendon length were the same as those that were palpated clinically, the landmarks used to assess patella height were different. Using the radiograph, patella height was measured from the posterior, superior margin of the patella to the anterior, inferior pole of the patella. According to, measurement of patella alta using a lateral radiograph and the landmarks described has been shown to be associated with minimal interobserver error (0.044 +- 0.047 with a Spearman's rank correlation coefficient of 0.86). Based on the calculated ratio values listed in table 2, this patient appeared to demonstrate bilateral patella alta that was worse on the left than on the right.
While the patient was standing, she was instructed to perform bilateral hip and knee flexion (partial squat). The patient reported pain at end-range with this movement. Passive correction of femoral adduction and rotation did not significantly decrease the symptoms reported. However, with a manual glide of the patella in an inferior direction, the patient did note a reduction of pain. This correction was provided to the patient in an effort to decrease the resting height of the patella in the trochlear groove prior to movement.
In sitting, the patient was first asked to actively extend each knee in order to assess her movement strategy. During these movements, the patient reported increased pain, and significant crepitus was noted. Manual gliding was performed to theoretically modify the resting height of the patella before knee extension was performed, resulting in decreased pain in both knees. The manual glide provided at the patella did not prevent the superior translation of the patella that might normally occur with quadriceps recruitment. Subsequent quadriceps strength testing was not performed because of the potential for pain
Palpation of relevant structures around each of the knees was also performed in sitting. Specifically, the patient reported no change in symptoms in either knee with palpation of the quadriceps and patellar tendons, the medial and lateral joint lines, or the infrapatellar fat pad. Additionally, there was no evidence of localized inflammation of the quadriceps or patellar tendons such as swelling or increased heat.
Active range of motion of the knee was assessed in supine. Knee flexion was 120 degrees bilaterally and knee extension was -5 degrees bilaterally. The patient reported anterior knee pain and stiffness at the end of knee flexion range of motion. Accessory motion of the patellofemoral joint was assessed and found to be limited bilaterally, but pain free. Accessory motion of the tibiofemoral joint was not assessed. Special tests to assess ligamentous and meniscal integrity in supine were not performed because the patient's history was not suggestive of either impairment.
In left and right side-lying, the patient had slight medial rotation of the top leg on both sides. The length of the TFL-ITB was tested using the modified Ober test, in which the knee was flexed to 90 degrees. The test was positive for impaired length of the TFL-ITB. The strength of the posterior gluteus medius was tested using standard manual muscle testing procedures as described by; the test results were 3/5 for both the left and the right.
In prone, no specific postural abnormalities were noted. Strength testing of the gluteus maximus was not performed secondary to the concern regarding her multiple hernia operations and the potential risk of injury to her lower back with end range hip extension. Next, functional activities such as sitting to standing, sleeping, gait, and stair climbing were evaluated. Transitioning from sitting to standing, the patient required upper extremity support and noted significant pain in her anterior knee. To modify her symptoms the patient was first cued to transition from sitting to standing at the edge of her chair. With this correction, the patient was able to stand more easily, but the anterior knee pain was unchanged. Therefore, using the same rationale as described previously, a force was applied manually to the patella in an inferior direction during the sit-to-stand motion, which resulted in a significant reduction of pain.
When asked to demonstrate her sleeping position, the patient assumed a side-lying position with her top lower extremity resting in hip flexion and medial rotation. Cues were provided to correct her sleeping position in order to determine whether the patient was more or less comfortable in side-lying in response to changes in alignment. When a pillow was placed between her lower extremities, the patient did, in fact, report increased comfort, but, again, no specific changes in knee pain were noted.
During the examination, the patient did not report pain during walking. However, excessive medial femoral rotation was observed during the stance phase of gait from foot flat to push-off. No corrections were provided at the time of the examination because her gait was not painful. By contrast, ascending and descending the stairs did increase her pain. It was not possible to provide a manual glide to the patella during this task, therefore, no conclusions could be made regarding the possible effects of patellar mal-alignment.
The patient was able to complete the examination described above with only a minimal increase in her symptoms. A diagnosis was determined based on these examination findings, and it was deemed safe to continue the initial visit and to provide appropriate treatment.
The examination findings were consistent with a diagnosis of Patellar Tracking Syndrome with Superior glide (APPENDIX A). This diagnosis describes anterior knee pain that is associated with an impaired relationship between the patella and the femur, which, in this case, was patella alta. The key finding supporting this diagnosis was the consistent decrease in pain associated with manual, inferior correction of the patella. In addition, the patient described diffuse anterior knee pain that was not specific to the quadriceps tendon, the patellar tendon, or the tibiofemoral joint. Pain underneath or around the patella is considered indicative of a patellar alignment and tracking problem, particularly when the pain is consistently exacerbated with activities such as, stair climbing, sitting to standing, and partial squat. Finally, open chain activities such as knee extension in sitting were also painful, which supports the diagnosis of Patella Tracking Syndrome with Superior Glide because knee extension from 90 degrees of knee flexion to 25 degrees can increase patellofemoral joint reaction force. Because patella alta seems to be associated with a decrease in the size of the contact area between the patella and the femur, any significant increase in the joint reaction force, such as that which occurs with active knee extension, could significantly change the overall contact stress within the patellofemoral joint.
The patient was seen for 11 visits, including the initial evaluation, over a period of 6 months. The extended duration of physical therapy was necessary to accommodate the patient's travel schedule, as well as, to provide a mechanism for which to monitor the long-term success of treatment. During this time period, the emphasis of the treatment provided to the patient was on the correction of the positional fault of the patella in both lower extremities using tape. However, to improve the effectiveness of the taping method used to correct patellar alignment, treatment also addressed the correction of the patient's movement impairments with exercise prescription, as well as, functional training for the management of symptoms throughout the day.
Following the initial evaluation, four exercises were prescribed to address issues with regards to muscle length and motor recruitment (table 3). These exercises were performed by the patient at subsequent visits for review, and corrections were provided to the patient as needed.
In an attempt to reduce the superior displacement of the patella, the patient was also instructed to perform patellar mobilizations in an inferior direction as illustrated by. The patient was instructed to perform three sustained inferior patellar glides on both knees for 30 seconds each. The patient was not educated on specific mobilization grades. Rather, she was instructed to mobilize the patella within a pain free range.
Exercises specific to the impairments found during an examination are certainly an important component of treatment. However, unless the patient modifies his or her performance of daily activities that are contributing to pain, the long-term success of a home exercise program could be limited. In the present case, transitioning from sitting to standing and stair climbing were contributing to the symptoms that she was experiencing. Therefore, the patient was educated on specific compensatory and component strategies of movement to reduce the amount of patellofemoral stress experienced during these daily activities (table 4).
Given the degree of her patella alta, exercises and education were not sufficient in reducing her pain to a tolerable level. According to, some form of external support is often needed to reduce the physical tissue stress at a particular joint and to control symptoms. Taping is one form of support often employed by physical therapists to provide stabilization to a joint or assistance to a particular movement. In this case, Leukotape was used to provide stabilization to the patella in order to reduce the stress associated with the superior displacement noted. Prior to taping, the patient was educated on the purpose of the tape, doffing instructions, and appropriate skin care following removal. Because the patient believed she might be allergic to the tape, she was instructed, after the initial examination, to apply a test strip of tape and to monitor the skin for itching, redness, or rash.
During her first follow-up visit, the patient reported that she did not experience an adverse skin reaction secondary to the test strip of tape. The patient, therefore, consented to the taping intervention and tape was applied to both knees. For this patient, a novel method of taping was employed. Tape was applied in an inverted "U" pattern over the anterior knee to apply an inferiorly directed force at the superior margin of the patella.
The procedures used to apply the tape in this fashion were as follows. The patient was positioned in long-sitting and the knee was supported by a small towel roll. Cover-roll was applied first to protect the skin from the adhesive of the Leukotape. To apply the Leukotape, a strip of tape approximately 12 inches long was positioned at the superior margin and was affixed in such a manner that half of the width of the tape was on the patella while the other half of the tape was over the quadriceps tendon. An inferior force was then applied through the tape to the patella with care taken not to compress the patella within the trochlear groove. As the inferior force was applied, the tape was affixed on either side of the knee forming an inverted "U" shape over the patella (figures 2 and 3). Three to four additional strips of Leukotape were applied in a staggered fashion to increase the stability of the support. Initially, the patient was taped bilaterally.
As the treatment progressed and the tape was deemed successful at reducing her symptoms, the patient was instructed how to tape her knees independently. The same method of taping described above was used by the patient to self-tape. Self-taping allowed the patient to provide a more consistent, inferior force to the patella to help relieve her symptoms. The patient was instructed to apply the tape unilaterally and to alternate which knee was taped in order to manage her pain bilaterally and to protect her skin. Periodically, the therapist reviewed the tape applied by the patient to ensure that the taping procedure was being performed correctly. The patient continued self-taping for both knees for the duration of therapy, and was instructed to tape herself as needed following discharge.
The final component of the intervention provided to the patient was education regarding the initiation and progression of a conditioning program for general health and fitness. As the patient progressed in therapy, she was instructed on the performance of a walking program to improve her cardiovascular health while minimizing her symptoms. Because the patient had access to a pool, she was advised about the potential benefits of water exercise and cross-training and was instructed to use the pool 1 to 2 times per week. When unable to exercise in pool, the patient was given the alternative of using a stationary bike instead.
During the course of therapy, the patient demonstrated compliance with taping, as well as, the prescribed home exercises and her conditioning program. Ultimately, the patient was motivated to improve and to address her health and weight concerns with appropriate exercise.
To summarize patient improvement over the time period for which she was seen for physical therapy, a novel assessment of patient progress was developed (figure 5). Specifically, seven indicators of patient progress chosen by the authors were obtained from the patient chart. These indicators were assessed at 6 different time points throughout the duration of treatment. All indictors, excluding whether the pain was constant or intermittent and the ability to participate in physical activity such as walking and swimming, were judged relative to baseline measures at the initial evaluation. Other indicators of progress were pain severity, pain with functional activity as reported by the patient, medication use, Knee Outcome Survey score, and global level of function as reported by the patient on the Knee Outcome Survey.
For each of the five indicators that were assessed relative to baseline measures a score was provided for each patient visit. If the indicator of progress was either not assessed or unchanged relative to baseline, a score of 0 was assigned. If the indicator of progress had improved relative to baseline a score of 1 was assigned. Conversely, if the indicator of progress had worsened, a score of -1 was assigned. For the indicators of progress that were not compared to baseline, a score of 0 or 1 was assigned according to the following method. If the pain was described as constant, a score of 0 was assigned whereas if the pain was described as intermittent, a score of 1 was assigned. Likewise, if the patient was unable to participate in physical exercise such as walking or swimming, a score of 0 was assigned. If the patient reported participation in physical exercise such as walking or swimming, a score of 1 was assigned. Therefore, for each visit assessed, the patient could receive a cumulative score representing patient progress as high as 7 or as low as -5. When applying this novel assessment of patient progress, it is clear that the patient did steadily improve before worsening at visit 8. Assessment of these same indicators of progress at discharge also demonstrated significant progress relative to both visit 8 and baseline measurements. A more detailed description of specific patient progress, including the rationale for the patient's worsened status at visit 8 follows.
After initiating patella taping, the patient reported feeling "100% better" by the third visit, which was approximately four weeks after the initial evaluation. During the 3rd visit, the patient noted that the transition from sitting to standing was easier and less painful and that the tape specifically improved her ability to ascend the stairs. Therefore, as noted previously, the patient was provided instructions for self-taping. By the 5th visit, the patient reported minimal pain in both knees (1-2/10 pain that was not constant) and improvement in all functional activities. The patient also noted that she had reduced her use of pain medication to 800 mg of Advil as needed. Because of the progress demonstrated to this point, the patient was instructed to begin the conditioning exercises as described previously and the frequency of physical therapy was reduced to one visit every two weeks.
The patient's symptoms, however, worsened by her 6th visit. She reported a general increase in pain with walking, sitting to standing, and stair climbing. The patient attributed her symptoms to an increase in her activity level. She was walking at the gym more frequently than had been recommended. Therefore, the patient was provided instructions regarding activity moderation and aquatic exercise to limit the cumulative stress on the patellofemoral joint.
By the 7th visit, taping and moderate exercise enabled the patient to manage her symptoms more appropriately. In fact, the patient reported that her pain was only minimal and that the taping was helpful. Thus, the patient was instructed to continue her home program of taping and exercise as prescribed and to return in 2-3 weeks for evaluation and follow-up.
When the patient returned for her 8th visit, she noted that she had progressively worsened. She was now having more pain with the transition from sitting to standing and with walking. Though she was compliant with the home exercise program and her conditioning routine (walking and swimming), the pain was starting to limit more of her functional abilities. At this point, the tape was no longer working to relieve her symptoms. Her regression was confirmed by the change in her KOS score. Upon re-evaluation at her 8th visit, the patient only scored a 38.5 on her Activities of Daily Living Scale and rated her level of function at 20% of normal.
The patient could not attribute her increase in symptoms to any specific activity or event. However, it was observed, that the tape on the patient's knee had been applied incorrectly. The tape was positioned superior to the margin of the patella around the distal quadriceps muscle and was providing no stabilization force (figure 6). The self-taping being performed by the patient was ineffective. Therefore, the patient was re-instructed on the appropriate taping technique and was asked to follow-up in one week.
Upon return to physical therapy after one week, the patient reported a significant improvement in her symptoms with the correction of the taping application. Indeed, the patient reported decreased pain with sit to stand and noted that she was able to walk approximately one mile on the track with minimal difficulty. Visual observation of the tape applied by the patient revealed that she had positioned the tape correctly. The patient was instructed to gradually progress her conditioning program, continue with the taping, and follow-up in one month.
Despite having to cope with an episode of pneumonia, the patient reported at the one-month follow-up (10th visit) that she had been able to manage her pain with the taping and exercise. In fact, the patient noted that she was having minimal difficulty with walking and was able to actively participate in a previously planned tour to Washington D.C. Her average pain was reported to be a 1-2/10 and she noted decreased use of pain medication (actual dosage was not provided). Stair climbing was still challenging, but the patient stated that it was easier relative to her baseline level of function at the initial evaluation. At this time, the patient completed a 3rd KOS. She scored a 56 on the Activities of Daily Living Scale and rated her level of function at 70% of normal (table 5).
In addition to the administration of the KOS, many of the tests assessed during the initial evaluation were re-evaluated at this visit (10th visit). Based on clinical measurements, the alignment of the patella had not changed significantly. The IS ratio calculated for the alignment of her right patella was 1.31 while the IS ratio for her left patella was 1.4. The patient did, however, demonstrate improvement in posterior gluteus medius strength to 3+/5 bilaterally and increased knee flexion range of motion (128 degrees on the right and 125 degrees on the left). Knee extension range of motion was not reassessed. Functionally, the patient reported minimal pain and no obvious movement impairments with sit to stand and gait. Stair climbing was first assessed without tape and was found to be painful. With the application of the tape to provide an inferior force to the patella, the patient reported a significant decrease in symptoms. Based on the results of this re-evaluation, it was clear that the patient had improved relative to her baseline level and that she was able to effectively manage her symptoms with tape and exercise.
The patient returned to therapy for follow-up two weeks later. During this visit, the patient subjectively noted that pain was no longer limiting function. Furthermore, she was walking 3-4 times per week without pain and was exercising in the pool 1-2 times per week. Taping and exercise were reviewed and the patient was discharged with instructions to continue her prescribed therapy.