PURPOSE: We intend to provide more objective data for diagnosis of the patellofemoral pain syndrome by analyzing the positional changes of the patella radiologically. MATERIALS AND METHODS: In 42 normal knees and in 91 knees of patients with the patellofemoral pain syndrome, the following 6 parameters were analyzed using a 30 degree flexion lateral view and a Merchant axial view: 1) the Insall and Salvati method, 2) the Blackburne and Peel method, 3) the Saille method, 4) the depth of the trochlea, 5) the sulcus angle, 6) and the congruence angle. RESULTS: Using the Blackburne and Peel method of assessing the height of patella, the ratio was 0.86 in the control group, in contrast to 0.92 in the patellofemoral pain syndrome group (P<0.05). The average value of the congruence angle was 2.9 in the control group, while it was -9.2 in patellofemoral pain syndrome group (P<0.05). The other parameters showed no statistical significance. CONCLUSION: This indicates that the patella alta by the Blackburne and Peel method and the increase of congruence angle are useful in the diagnosis of the patellofemoral pain syndrome.
Diagnosis ; Humans ; Knee ; Patella ; Patellofemoral Pain Syndrome*

BACKGROUND: Muscular imbalance in the core and hip is one of the major risk factors associated with PFPS. There is evidence that decreased strength of the hip musculature is present in individuals with PFPS. This decrease in hip strength can also affect the stability of the core and further predisposes an athlete to injury. OBJECTIVES: This is a cross-sectional study that compares the hip muscle strength and core stability of collegiate football players with and without PFPS. METHODS: 25 participants (10 with PFPS and 15 without PFPS) participated in the study. Hip strength was measured using a digital handheld dynamometer. Core stability was assessed through the McGill Core Strength test and the 8-stage stability test. RESULTS: The hip adductors showed to be significantly weaker in those with PFPS as compared to those without PFPS ( p=0.040). No differences were found in the hip flexor (p=0.812), hip extensor (p=0.460) and abductors (p=0.126) strength while the core musculature showed that there is a statistically significant difference on the endurance of the lateral core musculature (p<0.001) and trunk flexors (p=0.027) between the two groups. CONCLUSION Football athletes without PFPS in this study demonstrated greater core stability and hip adductor muscle strength compared to those without PFPS.
Patellofemoral Pain Syndrome ; Lower Extremity ; Football

As modern medicine getting deeply to understand ever-detailed anatomy,structure and animal mechanics of the patellofemoral joint, excessive lateral pressure syndrome, a very common patellofemoral disorder, has been reacquainted by the clinicians. On account to the complexity and variety of the etiology and the mechanism of the pain, still, there are many difficulties and arguments on the exact description of the clinical symptoms and the establishment of a universally accepted diagnostic criteria. Accurately grasping different causes, pathomechanisms and developmental stages of the disease would be especially important. As a result, rational choice of the pertinent procedures become the clinical lynchpin. This paper reviews domestic and international pertinent literatures in the past 10 years, and provide an overview of the latest study of anatomy, biomechanic, pathomechanism and clinical experience, anticipating to offer help on standardizing the diagnosis and treatment of ELPS.
Humans ; Pain ; complications ; diagnosis ; Pain Management ; Patellofemoral Joint ; Pressure ; Syndrome

OBJECTIVE: To determine the effects of isometric hip adduction and abduction on the activity of vastus medialis obliquus (VMO) and vastus lateralis (VL) during semisquat and squat exercise. METHOD: Thirty healthy male subjects without history of knee pain were recruited. Subjects performed a traditional exercise combined with hip adduction and abduction during semisquat and squat exercise. A total of 3 repetitions lasting 6 seconds each were executed following two-minute intervals. The EMG signals were collected from VMO and VL of the dominant leg. The data were normalized to the maximal isometric voluntary contraction of VMO and VL at 90degrees of knee flexion using isokinetic dynamometer and analysed in terms of their RMS values. RESULTS: The activity of both VMO and VL was significantly greater during both semisquat and squat exercise with hip adduction and abduction than without hip adduction and abduction. The VMO/VL ratio was significantly greater. The squat exercise produced significantly greater VMO and VL activity than the semisquat exercise, regardless of hip position. However, there were no significant differences in VMO/VL ratio between semisquat and squat exercise. CONCLUSION: Combining isometric hip adduction using theraband during semisquat exercise produced higher VMO/ VL ratio through more selective VMO activation and could be easy and effective rehabilitation program in patellofemoral pain syndrome.
Contracts ; Electromyography ; Exercise ; Hip ; Humans ; Knee ; Leg ; Male ; Patellofemoral Pain Syndrome ; Quadriceps Muscle

OBJECTIVE: Neuromuscular imbalance of vastus medialis obliquus and vastus lateralis muscles is one of the major causes of patellofemoral pain syndrome. This study was designed to evaluate the effect of the angular velocity on the electromyographic activities of vastus medialis obliquus and vastus lateralis during isokinetic cycling. METHOD: Fifteen healthy women (23.6+/-2.7 years) without any knee problem performed two sets of isokinetic bicycling using Motomed (RECK, Germany) at three different revolutions per minutes (30 RPM, 45 RPM, 60 RPM). Integrated electromyographic (iEMG) activities of vastus medialis obliquus and vastus lateralis were measured during cycling. RESULTS: iEMG activities of vastus medialis obliquus increased as angular velocity increased (p<0.05). The vastus medialis obliquus : vastus lateralis iEMG ratio at 60 RPM was significantly greater than the ratio at 30 RPM (p<0.05). CONCLUSION: Preferential vastus medialis obliquus activation was achieved by isokinetic cycling at high angular velocity. This suggests the meaningful therapeutic protocol for the patients with patellofemoral pain syndrome in altering neuromuscular imbalance between vastus medialis obliquus and vastus lateralis.
Bicycling ; Electromyography ; Female ; Humans ; Knee ; Muscles ; Patellofemoral Pain Syndrome ; Quadriceps Muscle*

Patellofemoral pain syndrome (PFS) is one of the most common types of anterior knee pain and many studies reported the patellofemoral malalignments (such as high patella, increased sulcus angle and increased congruence angle) as possible causes of the syndrone. In order to confirm this hypothesis, the difference of congruence, sulcus angles and patella height ratio in normal subjects and PFS patients was evaluated. The PFS subjects were selected according to the criterias of anterior knee pain, pain aggravation after the repeated knee flexion and extension motion. A combined knee injury was screened by MRI. We have compared our data to the previous studies of Merchant et al.(1974), Aglietti et al.(1983), and Dowd and Bently(1986). The radiographic studies were done on lateral view, Merchant view, and patella height was measured by Insall-Salvati method and Blackburn-Peel method. The sulcus angle and the congruence angle were measured on a Merchant view. The results showed that the average patella height of normal group was 1.00+/-0.17 by the Insall test and the patella index was 1.02?0.23. There was no statistical difference between normal and patient group of which the patella height was 0.96+/-0.16 by Insall test with patella index of 1.04?0.17. On Merchant view, the congruence angle was +/-7 +/-11 degrees, and the sulcus angle was 135.5+/-6 degrees in PFS patient group, and in normal group the congruence angle was +/-2 +/-14 degrees, and the sulcus angle was 136+/-5. A little statistical variation was noted in both group. Our results were not much different from previous studies except for the Aglietti's study in congruence angle. We concluded that the Insall test, patella index, congruence angle and sulcus angle could not help to idetify patellofemoral malalignment of knee joint in PFS patients.
Humans ; Knee ; Knee Injuries ; Knee Joint ; Magnetic Resonance Imaging ; Patella ; Patellofemoral Pain Syndrome*

OBJECTIVE: Inappropriate neural control of the quadriceps femoris muscle group has been implicated in patellofemoral pain syndrome (PFPS) and the methods of biomechanical assessment of PFPS has been developed recently. The aims of the present investigation were to evaluate the effects of therapeutic exercise in the alleviation of PFPS and to develope objective clinical test for PFPS. METHOD: We investigated the onset time of the isometric contraction of vastus medialis oblique muscle (VMO) and the vastus lateralis muscle (VL) under four different conditions: knee flexion and extension in weight bearing (standing) and non-weight bearing (sitting on chair) situations. For each condition, onset times of EMG activities and onset times for VMO and VL were determined from five trials of isometric contraction. In addition, we compared knee flexor and extensor torques in control group and subjects with PFPS. To evaluate the effects of the exercise we compared the onset time difference (onset time of VL-onset time of VM) and quadriceps muscle torque at pre- and post- exercise in PFPS groups. RESULTS: In PFPS group, onset time of VMO during knee extension was significantly longer than the onset time of VL and the knee extensor torque was considerably weaker in comparison with normal group. Although onset time difference was not changed after exercise program, there were significant increase in knee extensor torque in subjects with PFPS. CONCLUSION: The role of exercise in the rehabilitation of quadriceps functions is to reduce the pain, to strengthen the knee extensor, and further accurate diagnostic tools and methods for the result of therapeutic exercise in PFPS are needed.
Isometric Contraction ; Knee ; Patellofemoral Pain Syndrome* ; Quadriceps Muscle ; Rehabilitation ; Torque ; Weight-Bearing

OBJECTIVETo explore the therapeutic results of surgical treatment for patellofemoral pain syndrome.

METHODSOne hundred patients (35 males and 65 females, ranging from 50 to 70 years old with an average age of 63 years) with patellofemoral pain syndrome were randomly and equally divided into treatment group and control group. All patients underwent arthroscopic treatment. The patients in treatment group were treated with medial patellofemoral ligament overlap and lateral patellar retinaculum release, and the patients in control group were just treated with lateral patella retinaculum release which is a current widespread operation.

RESULTSAll patients were followed-up with the mean time of 13 months, and were evaluated with HSS (hospital for special surgery) scoring system for the therapeutic effect. The mean score of treatment group (73.52+/-11.17) and control group (65.50+/-13.70) had statistical difference (P<0.05), which indicated that the therapeutic effect of medial patellofemoral ligament overlap and lateral patellar retinaculum release for treatment of patellofemoral pain syndrome was satisfying.

CONCLUSIONCompared with lateral patellar retinaculum release, this procedure is superior in correcting the abnormal movement of patellofemoral joint, easily balancing patellofemoral joint space, effectively relieving the pain of anterior knee. No postoperative complications occur, such as intraarticular haematoma, necrosis and dislocation of patella and so on.

Aged ; Arthroscopy ; Female ; Humans ; Male ; Medial Collateral Ligament, Knee ; surgery ; Middle Aged ; Patellar Ligament ; surgery ; Patellofemoral Pain Syndrome ; surgery

OBJECTIVE: To observe the clinical efficacy of Kinesio Taping combined with electroacupuncture in the treatment of patellofemoral disorder in middle-aged and elderly exercise enthusiasts. METHODS: From April 2018 to April 2020, 62 middle-aged and elderly exercisers with patellofemoral disorder were selected and divided into observation group and control group. In the observation group, there were 30 cases:12 males and 18 females, aged from 35 to 66 years old, with an average age of (48.32±6.80) years old. The observation group was treated with Kinesio Taping and electroacupuncture . In the control group, there were 32 cases:12 males and 20 females, aged from 35 to 67 years old, with an averageage of (48.67±8.13) years old. The patients in the control group was treated with knee electroacupuncture. All the patients in both groups were treated once every other day, 3 times a week, for a total of 4 weeks. The VAS pain score and knee Lysholm score before and after treatment were compared between the two groups before and after treatment, and statistical analysis was conducted. RESULTS: In the control group, 2 patients were not satisfied with the curative effect after 2 weeks of treatment and gave up treatment, while the remaining 60 patients completed all the treatments. After 4 weeks of treatment, the VAS and Lyshlom scores of the control group were 2.73±1.46 and 75.63±8.62 respectively;the VAS and Lyshlom scores of the observation group were 2.02±1.85 and 83.31±5.53 respectively;the VAS and Lyshlom scores of the observation group and the control group were better than those before treatment, and the Lyshlom scores of the observation group were better than those of the control group. CONCLUSION Kinesio Taping combined with electroacupuncture is aimed at patellofemoral disorderof middle-aged and elderly sports enthusiasts. It has little trauma, can relieve pain and has a fast onset speed, which is readily accepted by patients, and promotes the rehabilitation of knee joint function of patients, thus providing a favorable reference for the promotion in clinical application.
Adult ; Aged ; Athletic Tape ; Electroacupuncture ; Female ; Humans ; Knee Joint ; Male ; Middle Aged ; Patellofemoral Pain Syndrome ; Treatment Outcome

BACKGROUNDIsolated patellofemoral osteoarthritis is not uncommon. Surgical treatment of isolated patellofemoral arthritis remains controversial and poses a challenging treatment dilemma. The present study aimed to evaluate the short-term results of patellofemoral arthroplasty for patients with isolated patellofemoral osteoarthritis.

METHODSWe analyzed 11 patellofemoral arthroplasties performed from March 2006 to September 2009 in 11 patients with isolated patellofemoral arthritis. The patients comprised 2 males and 9 females with an average age of 53.7 years (range, 46 - 74 years). Standard weightbearing radiographs were taken in the anteroposterior, lateral, and 45° axial views. The knee pain and functional status were evaluated by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scales and American Knee Society (AKS) scores. For comparison, 23 total knee arthroplasties in 23 patients with primary tibiofemoral osteoarthritis were matched according to age, gender, bilaterality and body mass index. The duration of follow-up was 23.7 months (range, 12 - 47 months).

RESULTSThe majority of the 11 patients experienced improvement in their patellofemoral symptoms after patellofemoral arthroplasty. The WOMAC scores improved considerably by 7.4 points with respect to pain and by 5.2 points with respect to function. The AKS scores also improved considerably by 23.9 points with respect to pain and 44.3 points with respect to function. Although the clinical outcomes after patellofemoral arthroplasty were not better than those after total knee arthroplasty, patellofemoral arthroplasty exhibited advantages in the shorter operation time, lower blood loss and increased postoperative range of motion. At the latest follow-up, there was no clinical or radiographic evidence of patellofemoral maltracking, loosening or wear.

CONCLUSIONSOn the basis of our experience in this relatively small series of patients with a short-term follow-up, patellofemoral arthroplasty is an effective treatment alternative to total knee arthroplasty in isolated patellofemoral arthritis. MRI and arthroscopy may contribute to define those patients with isolated patellofemoral degeneration.

Aged ; Arthroplasty, Replacement, Knee ; methods ; Female ; Humans ; Male ; Middle Aged ; Osteoarthritis, Knee ; diagnostic imaging ; surgery ; Patellofemoral Pain Syndrome ; diagnostic imaging ; surgery ; Radiography ; Treatment Outcome