Physical and arthroscopic examination techniques of the patellofemoral joint

Sex-based differences and relationship with the restricted knee flexion angle due to aging: a comparative study

BACKGROUND

The relationship between inferior patellar mobility (IPM) and knee flexion angle has yet to be elucidated. This study aimed to develop quantitative IPM measurement methods and clarify the relationship between IPM and knee flexion angle in community-dwelling older females.

METHODS

This was a cross-sectional study. Overall, 128 healthy older women (age 65-79 years) were recruited from the community to evaluate the relationship between IPM and knee flexion angle. This study was performed between May 2015 and December 2017. The reference value of and sex differences in IPM were evaluated in 205 healthy young adults aged between 19 and 21 years. IPM was compared between healthy older and young women and was objectively measured using our specially designed patellofemoral arthrometer (PFA). Patellar mobility was calculated by normalization to body height. IPM reliability was assessed before all measurements.

RESULTS

Intraclass correlation coefficients for intratester and intertester reliabilities varied from 0.87 to 0.99. The normal range based on two standard deviations of inferior patellar displacement/body height was 5.9-13.5% (young men), 5.1-14.3% (young women), and 1.2-8.8% (older women). IPM was significantly lower in older than young women (P < 0.001). There was a significant positive correlation (r = 0.72 and P < 0.01) between IPM and knee flexion angle in healthy older women unable to flex the knee joint fully.

CONCLUSIONS

Our PFA has good intratester and intertester reliability. The results suggest that IPM decreases with aging in women. IPM and knee flexion angle are correlated among older women unable to flex the knee joint fully.

CLINICAL TRIAL REGISTRATION

Not applicable.

What is the J-sign and why is it important?

PURPOSE OF REVIEW

Recurrent lateral patellofemoral instability is a complex condition that requires a thorough evaluation to optimize treatment. The J-sign test is classically part of the physical examination, but its significance and importance remain unclear. This review aims to describe how to perform the test and classify the observation as well as to analyze the most recent literature on its clinical applications.

RECENT FINDINGS

The J-sign test has been described as positive (present) or negative (absent), and classified using the quadrant method and the Donnell classification. Suboptimal inter-rater reliability has been shown for both classifications, making comparison between clinicians and studies challenging. The J-sign is most predominantly associated with patella alta, trochlear dysplasia, lateral force vector, and rotational abnormalities. A growing number of studies have shown a correlation between a positive J-sign and lower clinical outcome scores and higher rate of surgical failure.

SUMMARY

The J-sign is an important aspect of the physical examination in patients with recurrent lateral patellofemoral instability. Although there is no consensus on how to perform or classify the test, it can be used as a marker of severity of patellofemoral instability and is one of the tools available to guide the treatment plan.

Inter-rater Reliability of the Classification of the J-Sign Is Inadequate Among Experts

OBJECTIVE

The purpose of this study was to determine the inter-rater and intra-rater reliability of the symmetry, classification, and underlying pathoanatomy associated with the J-sign in patients with recurrent lateral patellofemoral instability.

STUDY DESIGN

Blinded, inter-rater reliability study.

SETTING

N/A.

PARTICIPANTS

Thirty patellofemoral joint experts.

INTERVENTIONS

Thirty clinicians independently assessed 30 video recordings of patients with recurrent lateral patellofemoral instability performing the J-sign test.

MAIN OUTCOME MEASURES

Raters documented J-sign symmetry and graded it according to the quadrant and Donell classifications. Raters indicated the most significant underlying pathoanatomy and presence of sagittal plane maltracking. Intra-rater reliability was assessed by 4 raters repeating the assessments. Mean pairwise simple and/or weighted Cohen's kappa were performed to measure inter-rater and intra-rater reliability, as well as calculation of percent agreement.

RESULTS

J-sign symmetry demonstrated fair inter-rater reliability (k = 0.26), whereas intra-rater reliability was moderate (k = 0.48). Inter-rater reliability for the quadrant and Donell classifications indicated moderate agreement, k = 0.51 and k = 0.49, respectively, whereas intra-rater reliability was k = 0.79 and k = 0.72, indicating substantial agreement. Inter-rater reliability of the foremost underlying pathoanatomy produced only slight agreement (k = 0.20); however, intra-rater reliability was substantial (k = 0.68). Sagittal plane maltracking demonstrated slight inter-rater agreement (k = 0.23) but substantial intra-rater agreement (k = 0.64).

CONCLUSIONS

The symmetry, classification, and underlying pathoanatomy of the J-sign demonstrated fair to moderate inter-rater reliability and moderate to substantial intra-rater reliability among expert reviewers using video recordings of patients with recurrent lateral patellofemoral instability. These findings suggest individual raters have a consistent standard for assessing the J-sign, but that these standards are not reliable between assessors.

LEVEL OF EVIDENCE

III.

Arthroscopic Patellofemoral Measurements Can Reliably Assess Patellar Instability

PURPOSE

To arthroscopically describe patellar position based on lateralization, tilt, and engagement, and compare measurements in normal, medial patellofemoral complex-(MPFC) deficient, and MPFC-reconstructed knees.

METHODS

In 10 cadaveric knees, arthroscopic patellar position was assessed by performing digital measurements on arthroscopic images obtained through a standard anterolateral portal. Lateralization was measured as millimeters overhang of the patella past the lateral edge of the lateral femoral condyle, viewing from the lateral gutter. Patellar tilt was calculated as the difference in medial and lateral distances from the patella to the trochlea, viewing from the sunrise view. Patellotrochlear distance was measured as the anteroposterior distance between the central trochlear groove and patella on the sunrise view. Measurements were obtained at 10° intervals of knee flexion from 0° to 90°, in intact knees (group 1), after arthroscopically transecting the MPFC fibers (group 2), and after MPFC reconstruction (group 3). Optimal cutoff values were identified to distinguish between intact versus MPFC-deficient states.

RESULTS

When compared to group 1, group 2 demonstrated increased patellar lateralization by 22.5% at 0°-40° knee flexion (P = .006), which corrected to baseline in group 3 (P = .006). Patellar tilt measurements demonstrated no differences between groups. Patellotrochlear distance increased by 21.0% after MPFC transection (P = .031) at 0°-40° knee flexion, with correction to baseline after MPFC reconstruction (P = .031). More than 7 mm of lateral overhang at 20°-30° flexion and >6 mm of patellotrochlear distance at 10°-20° flexion were found to indicate MPFC deficiency.

CONCLUSIONS

Utilizing standardized arthroscopic views, we identified significant increases in patellar lateralization and patellotrochlear distance in early knee flexion angles after MPFC transection, and these changes normalized after MPFC reconstruction.

CLINICAL RELEVANCE

Arthroscopic assessments of patellar position may be useful in evaluating patellofemoral stability during patellar stabilization surgery.

Comparing goniometric and radiographic measurement of Q angle of the knee

Background

The Q angle is a relevant clinical diagnostic measurement to detect various disorders of the knee. The common method used to measure the Q angle in the routine clinical practice is by radiography. An alternative to radiographic measurement is goniometry, by which exposure to x-rays can be avoided.

Objectives

To compare and correlate the goniometric measurement of Q angle with radiographic measurement of the Q angle in patients with acute knee pain.

Methods

We selected 45 patient participants with a mean age of 32.5 years who satisfied the inclusion criteria for this study. All the patients underwent goniometric measurement of the Q angle followed by x-ray imaging of the entire lower limb. Later the bony prominences were marked on the x-ray image and the Q angle formed was measured using a protractor. The Pearson correlation coefficient between the goniometric and radiographic measurements was determined.

Results

We found a significant relationship between Q angles obtained using a goniometer and x-ray imaging in the supine position (r = 0.91, P = 0.001). The mean difference between the goniometric measurement of Q angle and the radiographic measurement was 0.1°, which is not significant.

Conclusions

Goniometry can be used to measure Q angle as accurately as radiography, and can be used as an inexpensive and radiation free alternative.

WITHDRAWN: Exercise therapy for patellofemoral pain syndrome

The review was withdrawn, as of Issue 1, 2015, because it has been superceded by a new Cochrane review: van der Heijden RA, Lankhorst NE, van Linschoten R, Bierma‐Zeinstra SMA, van Middelkoop M. Exercise for treating patellofemoral pain syndrome. Cochrane Database of Systematic Reviews 2015, Issue 1. Art. No.: CD010387. DOI: 10.1002/14651858.CD010387.pub2.

The editorial group responsible for this previously published document have withdrawn it from publication.

Exercise for treating patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome (PFPS) is a common knee problem, which particularly affects adolescents and young adults. PFPS, which is characterised by retropatellar (behind the kneecap) or peripatellar (around the kneecap) pain, is often referred to as anterior knee pain. The pain mostly occurs when load is put on the knee extensor mechanism when climbing stairs, squatting, running, cycling or sitting with flexed knees. Exercise therapy is often prescribed for this condition.

OBJECTIVES

To assess the effects (benefits and harms) of exercise therapy aimed at reducing knee pain and improving knee function for people with patellofemoral pain syndrome.

SEARCH METHODS

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (May 2014), the Cochrane Central Register of Controlled Trials (2014, Issue 4), MEDLINE (1946 to May 2014), EMBASE (1980 to 2014 Week 20), PEDro (to June 2014), CINAHL (1982 to May 2014) and AMED (1985 to May 2014), trial registers (to June 2014) and conference abstracts.

SELECTION CRITERIA

Randomised and quasi-randomised trials evaluating the effect of exercise therapy on pain, function and recovery in adolescents and adults with patellofemoral pain syndrome. We included comparisons of exercise therapy versus control (e.g. no treatment) or versus another non-surgical therapy; or of different exercises or exercise programmes.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials based on pre-defined inclusion criteria, extracted data and assessed risk of bias. Where appropriate, we pooled data using either fixed-effect or random-effects methods. We selected the following seven outcomes for summarising the available evidence: pain during activity (short-term: ≤ 3 months); usual pain (short-term); pain during activity (long-term: > 3 months); usual pain (long-term); functional ability (short-term); functional ability (long-term); and recovery (long-term).

MAIN RESULTS

In total, 31 heterogeneous trials including 1690 participants with patellofemoral pain are included in this review. There was considerable between-study variation in patient characteristics (e.g. activity level) and diagnostic criteria for study inclusion (e.g. minimum duration of symptoms) and exercise therapy. Eight trials, six of which were quasi-randomised, were at high risk of selection bias. We assessed most trials as being at high risk of performance bias and detection bias, which resulted from lack of blinding.The included studies, some of which contributed to more than one comparison, provided evidence for the following comparisons: exercise therapy versus control (10 trials); exercise therapy versus other conservative interventions (e.g. taping; eight trials evaluating different interventions); and different exercises or exercise programmes. The latter group comprised: supervised versus home exercises (two trials); closed kinetic chain (KC) versus open KC exercises (four trials); variants of closed KC exercises (two trials making different comparisons); other comparisons of other types of KC or miscellaneous exercises (five trials evaluating different interventions); hip and knee versus knee exercises (seven trials); hip versus knee exercises (two studies); and high- versus low-intensity exercises (one study). There were no trials testing exercise medium (land versus water) or duration of exercises. Where available, the evidence for each of seven main outcomes for all comparisons was of very low quality, generally due to serious flaws in design and small numbers of participants. This means that we are very unsure about the estimates. The evidence for the two largest comparisons is summarised here. Exercise versus control. Pooled data from five studies (375 participants) for pain during activity (short-term) favoured exercise therapy: mean difference (MD) -1.46, 95% confidence interval (CI) -2.39 to -0.54. The CI included the minimal clinically important difference (MCID) of 1.3 (scale 0 to 10), indicating the possibility of a clinically important reduction in pain. The same finding applied for usual pain (short-term; two studies, 41 participants), pain during activity (long-term; two studies, 180 participants) and usual pain (long-term; one study, 94 participants). Pooled data from seven studies (483 participants) for functional ability (short-term) also favoured exercise therapy; standardised mean difference (SMD) 1.10, 95% CI 0.58 to 1.63. Re-expressed in terms of the Anterior Knee Pain Score (AKPS; 0 to 100), this result (estimated MD 12.21 higher, 95% CI 6.44 to 18.09 higher) included the MCID of 10.0, indicating the possibility of a clinically important improvement in function. The same finding applied for functional ability (long-term; three studies, 274 participants). Pooled data (two studies, 166 participants) indicated that, based on the 'recovery' of 250 per 1000 in the control group, 88 more (95% CI 2 fewer to 210 more) participants per 1000 recovered in the long term (12 months) as a result of exercise therapy. Hip plus knee versus knee exercises. Pooled data from three studies (104 participants) for pain during activity (short-term) favoured hip and knee exercise: MD -2.20, 95% CI -3.80 to -0.60; the CI included a clinically important effect. The same applied for usual pain (short-term; two studies, 46 participants). One study (49 participants) found a clinically important reduction in pain during activity (long-term) for hip and knee exercise. Although tending to favour hip and knee exercises, the evidence for functional ability (short-term; four studies, 174 participants; and long-term; two studies, 78 participants) and recovery (one study, 29 participants) did not show that either approach was superior.

AUTHORS' CONCLUSIONS

This review has found very low quality but consistent evidence that exercise therapy for PFPS may result in clinically important reduction in pain and improvement in functional ability, as well as enhancing long-term recovery. However, there is insufficient evidence to determine the best form of exercise therapy and it is unknown whether this result would apply to all people with PFPS. There is some very low quality evidence that hip plus knee exercises may be more effective in reducing pain than knee exercise alone.Further randomised trials are warranted but in order to optimise research effort and engender the large multicentre randomised trials that are required to inform practice, these should be preceded by research that aims to identify priority questions and attain agreement and, where practical, standardisation regarding diagnostic criteria and measurement of outcome.

Effectiveness of exercise therapy in treatment of patients with patellofemoral pain syndrome: systematic review and meta-analysis

BACKGROUND AND PURPOSE

This systematic review and meta-analysis was accomplished to determine whether exercise therapy is an effective intervention to reduce pain and patient-reported measures of activity limitations and participation restrictions (PRMALP) in patients with patellofemoral pain.

DATA SOURCES AND STUDY SELECTION

Randomized controlled trials in English and German languages published in the MEDLINE, Physiotherapy Evidence Database (PEDro), International Clinical Trials Registry Platform, and Cochrane databases were searched. Eligibility was assessed in 2 stages. The methodological quality of the studies was rated using the PEDro scale. Data were pooled using random-effects meta-analysis, allowing for variability among studies. For clinical use, overall estimates were re-expressed in the original visual analog scale scores. Significance was set at 5%.

DATA EXTRACTION AND DATA SYNTHESIS

Fifteen studies, with a total of 748 participants, were included and pooled for the meta-analysis. Six studies compared the effect of exercise therapy with a control group receiving neither exercise therapy nor another intervention. Four studies compared the effect of exercise therapy versus additive therapy, and 5 studies compared different exercise interventions. In both comparisons, exercise therapy resulted in strong pain reduction and improvement of PRMALP effects. Significant short-term effects (≤12 weeks) of exercise therapy were found for pain and PRMALP, whereas long-term effects (≥26 weeks) were observed for PRMALP only.

LIMITATIONS AND CONCLUSION

The 15 studies included in this analysis were of variable quality. Large-scale, high-quality randomized controlled trials are needed to further the evaluation of the possible effects of different exercise therapy modalities on patellofemoral pain. This meta-analysis presents evidence that exercise therapy has a strong pain-reducing effect and decreases PRMALP in patients with patellofemoral pain. However, the question of which exercise modality yields the strongest reducing effect on pain and PRMALP remains unanswered.

Arthroscopic evaluation of patellofemoral congruence with rotation of the knee joint and electrical stimulation of the quadriceps

PURPOSE

The aim of this study was to investigate the pathoanatomic features of patellar instability by arthroscopically comparing patellofemoral congruence with rotation of the knee joint and/or electrical stimulation of the quadriceps (ESQ) between knees with and without patellar instability.

METHODS

We retrospectively examined 83 knee joints in 83 patients. The joints were classified into 2 groups: group 1 comprised those without a history of patellar dislocation and included 59 patients (25 male and 34 female patients), and group 2 comprised those with a history of patellar dislocation and included 24 patients (9 male and 15 female patients). Evaluation of patellofemoral congruence at 30° of flexion of the knee joint was conducted based on an axial radiograph and arthroscopic findings. The congruence angle was measured on the radiograph. The position of the patellar central ridge (PPCR) on the trochlear groove during arthroscopy was measured using still video frames of knee joints with rotational stress and/or ESQ. Statistical differences in the measurements between the 2 groups were assessed with the unpaired t test and the area under the receiver operating characteristic curve of each measurement.

RESULTS

There were significant differences (P < .0001) between the 2 groups in the congruence angle on radiographs and PPCR in knee joints with rotational stress and/or ESQ on arthroscopy. External and internal rotation of the knee joint caused lateral and medial patellar shift, respectively, in both groups, but the shift was significantly larger in group 2. ESQ in addition to rotation caused further patellar shift in group 2 but reduced patellar shift in group 1. Measurement of PPCR with external rotation of the knee and ESQ was the only method to show an area under the receiver operating characteristic curve of 1.

CONCLUSIONS

There were significant differences in the effects of rotation of the knee joint and/or ESQ on patellofemoral congruence at 30° of flexion of the knee joint on arthroscopy between knees with and without patellar instability.

LEVEL OF EVIDENCE

Level III, diagnostic study of nonconsecutive patients.

Hallux valgus in patients with patellofemoral pain syndrome

The aim of this study was to investigate the presence of hallux valgus (HV) in patellofemoral pain syndrome (PFPS). Ninety-nine patients with unilateral patellofemoral pain participated. The study was designed with each subject acting as their own internal control by using the unaffected limb for comparison. The HV and intermetatarsal angles were measured by weight-bearing anteroposterior radiographs in patients. Eighty-four out of 99 patients had an abnormal HV angle on the affected side and 78 of 99 patients had an abnormal HV angle on the unaffected side. There were significant differences in the HV angle between affected and unaffected sides (P = 0.003). This study is the first to demonstrate the relationship between HV and PFPS. Further comprehensive biomechanical studies are warranted to analyse the relationship between HV and PFPS.

WITHDRAWN: Orthotic devices for treating patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome is a frequently reported condition in active adults. A wide variety of conservative treatment strategies have been described. As yet, no optimal strategy has been identified. Application of orthotic devices e.g. knee braces, knee straps, forms of taping of the knee, active training devices, knee sleeves and inlay soles to support the foot have been advocated to treat this condition.

OBJECTIVES

To assess the effectiveness of foot and knee orthotics for treatment of patellofemoral pain syndrome.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Controlled Trials register (Issue 2, 2000), MEDLINE (January 1966 to March 2000; EMBASE (January 1988 to March 2000); CINAHL (January 1982 to March 2000) and PEDro (up to March 2000). Relevant orthotic companies were contacted. The date of the most recent search was May 2000.

SELECTION CRITERIA

All randomised and quasi-randomised trials comparing the effectiveness of knee or foot orthotics for treatment of patellofemoral pain syndrome were selected. Trials describing the use of orthotic devices in conjunction with operative treatment were excluded.

DATA COLLECTION AND ANALYSIS

Three reviewers independently assessed methodological quality of the identified trials by use of a modified version of the Cochrane Bone, Joint and Muscle Trauma Group assessment tool, consisting of 11 items. Two reviewers extracted data without blinding. Trialists were contacted to obtain missing data.

MAIN RESULTS

Five trials involving 362 participants were included in this review. Five other trials await possible inclusion if further information can be obtained. Due to clinical heterogeneity, we refrained from statistical pooling and conducted analysis by grading the strength of scientific evidence. The level of obtained research-based evidence was graded as limited as all trials were of low methodological quality.This limited research-based evidence showed the Protonics brace at six week follow-up was significantly more effective for decrease in pain (weighted mean difference (WMD) between groups 3.2; 95% confidence interval (CI) 2.8 to 3.6), functional improvement on the Kujala score (WMD 45.6; 95% CI 43.4 to 47.7) and change in patellofemoral congruence angle (WMD 17.2; 95% CI 14.1 to 20.3) when compared to no treatment. A comprehensive programme including tape application was significantly superior to a monitored exercise programme without tape application for decrease in worst pain (WMD 1.6; 95% CI 0.4 to 2.8) and usual pain (WMD 1.2; 95% CI 0.2 to 2.1), and clinical change and functional improvement questionnaire scores at four weeks follow-up.The trials reported statistically significant differences in patient satisfaction after applied therapy (WMD 3.3; 95% CI 0.5 to 6.1) in favour of the McConnell regimen compared with the Coumans bandage at six weeks follow-up.

AUTHORS' CONCLUSIONS

The evidence from randomised controlled trials is currently too limited to draw definitive conclusions about the use of knee and foot orthotics for the treatment of patellofemoral pain. Future high quality trials in this field are warranted.

The reliability and validity of the Q-angle: a systematic review

The quadriceps or Q-angle is an index of the vector for the combined pull of the extensor mechanisms and the patellar tendon. It is used as an indicator for patellofemoral joint dysfunction. The purpose of this article is to systematically review and appraise the literature to determine the reliability and validity of this test. An electronic database search was performed accessing AMED, British Nursing Index, CINAHL, the Cochrane database, EMBASE, ovid Medline, Physiotherapy Evidence Database (PEDro), PsycINFO, Pubmed and Zetoc to April 2008. All English language, human subject, clinical trials, assessing the inter- or intra-tester reliability, or the criterion validity, were included. The Critical Appraisal Skills Programme appraisal tool was used to establish the methodological quality of each study. Ten articles including 569 control and 179 patellofemoral disorder knees were reviewed. The findings suggest that there is considerable disagreement on the reliability and validity of the clinical Q-angle measurement. This may be due to a lack of standardisation in the measurement procedure. Further study is advocated to re-evaluate this topic using well-designed, and sufficiently large observational studies of specific patellofemoral dysfunction populations.

Comparison of patellar mobility in female adults with and without patellofemoral pain

STUDY DESIGN

Case control study.

OBJECTIVE

To compare the patellar mobility of female adult subjects with and without patellofemoral pain (PFP).

BACKGROUND

Although abnormal patellar mobility is believed to be one of the causes of PFP, there is currently no published evidence to support this contention. In part, this lack of evidence is because a reliable clinical measurement method to measure patellar mobility and objective criteria to define abnormal patellar mobility have not been established.

METHODS AND MEASURES

The study sample was comprised of 22 females with PFP (PFP group) and 22 females who had no knee pain (control group), matched by age, height, and body mass index to the subjects with PFP. Patellar mobility was measured objectively using a specially designed apparatus. Measurements of lateral and medial patellar displacement, patellar mobility balance (lateral minus medial patellar displacement), lateral patellar mobility index (lateral patellar displacement divided by patellar width), and medial patellar mobility index (medial patellar displacement divided by patellar width) were used.

RESULTS

Lateral and medial patellar mobility values were not significantly different between the individuals in the PFP and control groups. When normal patellar mobility was arbitrarily defined as the average mobility +/- 2 SDs, based on the data from the control group, normal lateral patellar displacement was within a range of 7.2 to 17.6 mm and normal medial patellar displacement was within a range of 6.8 to 14.0 mm. The intraclass correlation coefficient for intratester and intertester reliability of lateral and medial patellar displacement measurements varied from 0.80 to 0.97.

CONCLUSION

Although there were no significant differences in patellar mobility between females with and without PFP, these measurements give reference information about normal patellar mobility for this group.

LEVEL OF EVIDENCE

Diagnosis, level 5.

The diagnostic value of the Clarke sign in assessing chondromalacia patella

CONTEXT

Various techniques have been described for assessing conditions that cause pain at the patellofemoral (PF) joint. The Clarke sign is one such test, but the diagnostic value of this test in assessing chondromalacia patella is unknown.

OBJECTIVE

To (1) investigate the diagnostic value of the Clarke sign in assessing the presence of chondromalacia patella using arthroscopic examination of the PF joint as the "gold standard," and (2) provide a historical perspective of the Clarke sign as a clinical diagnostic test.

DESIGN

Validation study.

SETTING

All patients of one of the investigators who had knee pain or injuries unrelated to the patellofemoral joint and were scheduled for arthroscopic surgery were recruited for this study.

PATIENTS OR OTHER PARTICIPANTS

A total of 106 otherwise healthy individuals with no history of patellofemoral pain or dysfunction volunteered.

MAIN OUTCOME MEASURE(S)

The Clarke sign was performed on the surgical knee by a single investigator in the clinic before surgery. A positive test was indicated by the presence of pain sufficient to prevent the patient from maintaining a quadriceps muscle contraction against manual resistance for longer than 2 seconds. The preoperative result was compared with visual evidence of chondromalacia patella during arthroscopy.

RESULTS

Sensitivity was 0.39, specificity was 0.67, likelihood ratio for a positive test was 1.18, likelihood ratio for a negative test was 0.91, positive predictive value was 0.25, and negative predictive value was 0.80.

CONCLUSIONS

Diagnostic validity values for the use of the Clarke sign in assessing chondromalacia patella were unsatisfactory, supporting suggestions that it has poor diagnostic value as a clinical examination technique. Additionally, an extensive search of the available literature for the Clarke sign reveals multiple problems with the test, causing significant confusion for clinicians. Therefore, the use of the Clarke sign as a routine part of a knee examination is not beneficial, and its use should be discontinued.

Patellofemoral joint kinematics in individuals with and without patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome is a prevalent condition in young people. While it is widely believed that abnormal patellar tracking plays a role in the development of patellofemoral pain syndrome, this link has not been established. The purpose of this cross-sectional case-control study was to test the hypothesis that patterns of patellar spin, tilt, and lateral translation make it possible to distinguish individuals with patellofemoral pain syndrome and clinical evidence of patellar malalignment from those with patellofemoral pain syndrome and no clinical evidence of malalignment and from individuals with no knee problems.

METHODS

Three-dimensional patellofemoral joint kinematics in one knee of each of sixty volunteers (twenty in each group described above) were assessed with use of a new, validated magnetic resonance imaging-based method. Static low-resolution scans of the loaded knee were acquired at five different angles of knee flexion (ranging between -4 degrees and 60 degrees). High-resolution geometric models of the patella, femur, and tibia and associated coordinate axes were registered to the bone positions on the low-resolution scans to determine the patellar motion as a function of knee flexion angle. Hierarchical modeling was used to identify group differences in patterns of patellar spin, tilt, and lateral translation.

RESULTS

No differences in the overall pattern of patellar motion were observed among groups (p>0.08 for all global maximum likelihood ratio tests). Features of patellar spin and tilt patterns varied greatly between subjects across all three groups, and no significant group differences were detected. At 19 degrees of knee flexion, the patellae in the group with patellofemoral pain and clinical evidence of malalignment were positioned an average of 2.25 mm more laterally than the patellae in the control group, and this difference was marginally significant (p=0.049). Other features of the pattern of lateral translation did not differ, and large overlaps in values were observed across all groups.

CONCLUSIONS

It cannot be determined from our cross-sectional study whether the more lateral position of the patella in the group with clinical evidence of malalignment preceded or followed the onset of symptoms. It is clear from the data that an individual with patellofemoral pain syndrome cannot be distinguished from a control subject by examining patterns of spin, tilt, or lateral translation of the patella, even when clinical evidence of mechanical abnormality was observed.

Structural parameters of the vastus medialis muscle and its relationship to patellofemoral joint deterioration

Vastus medialis (VM) muscle dysfunction and abnormal limb alignment are commonly observed in patients who experience changes in patellofemoral joint (PFJ) function, leading many clinicians to assume that there is a direct relationship between VM structural parameters, leg alignment, and PFJ dysfunction. This study tested the hypothesis that there is a relationship between structural parameters of the VM muscle, limb alignment, and the location and severity of patellofemoral joint deterioration (PFJD). The dissection study used 32 limbs from 24 intact cadavers. Data were collected on limb alignment, angle of VM muscle fibers below the superior aspect of the patella, length of VM inserting on the medial aspect of the patella, and severity and location of PFJD. Parametric and nonparametric statistical analyses illustrated that PFJD was most commonly located on the middle third of the medial half of the patellar articular surface. The severity of PFJD did not vary with location. There was no significant correlation between any of VM insertion length, VM fiber angle, limb alignment, and PFJD location and severity lpar;r(2) < 0.34). The results of this study did not support the hypothesis of a relationship between structural parameters of the VM muscle, limb alignment, and the location and severity of PFJD in this subject group. Future research should examine the relationship between functional parameters of the entire quadriceps muscle group and PFJ dysfunction.

Physical Examination and Patellofemoral Pain Syndrome

Patellofemoral pain syndrome, which accounts for 25% of all sports-related knee injuries, is multifactorial in origin. A combination of variables, including abnormal lower limb biomechanics, soft-tissue tightness, muscle weakness, and excessive exercise, may result in increased cartilage and subchondral bone stress, patellofemoral pain, and subtle or more overt patellar maltracking. Because of the multiple forces affecting the patellofemoral joint, the clinical evaluation and treatment of this disorder is challenging. An extensive search of the literature revealed no single gold-standard test maneuver for that disorder, and the reliability of the maneuvers described was generally low or untested. An abnormal Q-angle, generalized ligamentous laxity, hypomobile or hypermobile tenderness of the lateral patellar retinaculum, patellar tilt or mediolateral displacement, decreased flexibility of the iliotibial band and quadriceps, and quadriceps, hip abductor, and external rotator weakness were most often correlated with patellofemoral pain syndrome.

Efeitos na medida do ângulo Q com a contração isométrica voluntária máxima do músculo quadricipital

A proposta deste estudo foi verificar a diferença entre o ângulo quadricipital em indivíduos sintomáticos e assintomáticos, em duas diferentes situações de exame, com o quadríceps relaxado e em contração isométrica voluntária máxima (CIVM) através da mensuração radiográfica para contribuir na avaliação e tratamento de pacientes com disfunção femoropatelar (DFP). Foram avaliadas 20 mulheres (40 joelhos), com idade média de 21 anos, através de método radiológico padronizado. Os indivíduos foram posicionados em decúbito dorsal com um estabilizador podálico em "U", com os membros inferiores relaxados, com a utilização de película de chumbo sobre a tuberosidade anterior da tíbia. Para a análise estatística foram utilizadas as médias dos grupos assintomático e sintomático, em estado de relaxamento e em CIVM, e o teste t de Student, com nível de significância de p < 0,05. Os valores médios do ângulo Q para os assintomáticos foram de 17,15° em relaxamento e de 14,5° em CIVM, enquanto os sintomáticos apresentaram 21,45° e 15,8°, respectivamente. Nos resultados para a análise da igualdade entre os grupos sintomáticos e assintomáticos no estado de relaxamento obteve-se p = 0,004, e para o estado de contração isométrica voluntária máxima, p = 0,29. Considerando os dados obtidos no presente estudo, pode-se verificar que em estado de relaxamento há diferença entre o valor do ângulo Q entre indivíduos sintomáticos e assintomáticos, sendo este maior nos portadores da DFP, enquanto que em estado de contração isométrica máxima do músculo quadricipital não houve diferença estatística, ocorrendo redução do ângulo em ambos os grupos.

Efficacy of Isokinetic Exercise on Joint Position Sense and Muscle Strength in Patellofemoral Pain Syndrome

OBJECTIVE

The objective of this study was to demonstrate the impairment of knee joint position sense in individuals with patellofemoral pain syndrome and investigate the effects of isokinetic exercise on knee joint position sense and muscle strength.

DESIGN

A total of 24 male patients complaining of anterior knee pain caused by overexertion and 24 male healthy individuals without symptoms were included for this investigation. Isokinetic exercise protocol was carried out at angular velocities of 60 degrees/sec and 180 degrees/sec. These sessions were repeated three times per week and lasted for 6 wks. At the beginning and after 6 wks of knee passive joint position sense, quadriceps and hamstring muscle strength and pain assessments were performed.

RESULTS

After the isokinetic exercise, flexion peak torque (P < 0.05), extension peak torque (P < 0.01), flexion total work (P < 0.001), extension total work (P < 0.001), passive reproduction of knee joint position sense for 40 degrees of flexion (P < 0.05) and 50 degrees of extension (P < 0.01), and pain score (P < 0.001) improved significantly in the patellofemoral pain syndrome group.

CONCLUSION

Isokinetic exercises have positive effects on passive position sense of knee joints, increasing the muscular strength and work capacity. These findings show that using the present isokinetic exercise in rehabilitation protocols of patients with patellofemoral pain syndrome not only improves the knee joint stabilization but also the proprioceptive acuity.

Structural parameters of the vastus medialis muscle

This research was designed to evaluate musculoskeletal anatomy of the quadriceps region relative to the patellofemoral joint. The hypothesis for the study was that the oblique portion (VMO) of the vastus medialis muscle (VM) is anatomically positioned to function primarily as an active medial stabilizer of the patella. Because many clinicians believe that the VMO functions independently as an active medial stabilizer of the patellofemoral joint (PFJ), PFJ rehabilitation protocols commonly target the VMO in an attempt to restore normal joint mechanics. It is unclear whether this purported selective function is supported by the underlying anatomical structure. Through dissection of 32 limbs from 24 intact cadavers with normal patellar alignment, data were collected on VM fiber alignment and innervation, the presence of fascial plane, and the length of VM about the patella. Statistical analyses demonstrated that the oblique and long heads of the VM muscle had significantly different (P < 0.05) angles of fiber orientation, as expected. When measurements were taken relative to a vertical axis (standardizing limb alignment between cadavers), the difference in fiber angles between oblique and long heads of the VM was reduced significantly. Additionally, < 10% of the length of the VM muscle inserted directly on the medial aspect of the patella, and there was no anatomical evidence of a fascial plane or separate innervation for the oblique and long heads of the VM. The results of the study did not support the hypothesis that the VMO is anatomically positioned to function primarily as an active medial stabilizer of the patella.

Effects of foot orthoses on quality of life for individuals with patellofemoral pain syndrome

STUDY DESIGN

Repeated-measures analysis of intervention.

OBJECTIVES

To determine the effects of foot orthoses on quality of life for individuals with patellofemoral pain who demonstrate excessive foot pronation.

BACKGROUND

Foot orthoses are a common intervention for patients with patellofemoral pain. Limited information is available, however, regarding the effects of foot orthoses on quality of life for these patients.

METHODS AND MEASURES

Sixteen subjects with patellofemoral pain who also exhibited signs of excessive foot pronation were studied. Subjects underwent a 2-week period of baseline study followed by custom foot orthotic intervention. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was administered to subjects at the time of screening, just prior to foot orthotic intervention, and at 2 weeks and 3 months following foot orthotic intervention.

RESULTS

Wilcoxon matched-pairs signed-rank test results indicated statistically significant improvements in the pain and stiffness subscales 2 weeks following the start of foot orthotic intervention. All WOMAC subscale scores were significantly improved at 3 months compared with preintervention measurements.

CONCLUSIONS

Custom-fitted foot orthoses may improve patellofemoral pain symptoms for patients who demonstrate excessive foot pronation.

Relation between isokinetic muscle strength and functional capacity in recreational athletes with chondromalacia patellae

OBJECTIVES

To investigate the effects of isokinetic exercise on pain and functional test scores of recreational athletes with chondromalacia patellae (CMP) and to examine the correlation between isokinetic parameters and functional tests or pain score.

METHODS

The functional ability of 30 recreational athletes with unilateral CMP was evaluated using six different tests. Pain scores were assessed during daily activities before and after the treatment protocol. Isokinetic exercise sessions were carried out at angular velocities of 60 degrees /s (25-90 degrees range of flexion) and 180 degrees /s (full range). These sessions were repeated three times a week for six weeks.

RESULTS

Quadriceps and hamstring peak torque, total work, and endurance ratios had improved significantly after the treatment, as did the functional parameters and pain scores. There was a poor correlation between the extensor endurance ratio and one leg standing test. A moderate correlation between the visual analogue scale and the extensor endurance ratio or flexion endurance ratio was also found.

CONCLUSIONS

The isokinetic exercise programme used in this study had a positive effect on muscle strength, pain score, and functional ability of knees with CMP. The improvement in the functional capacity did not correlate with the isokinetic parameters.

Pharmacotherapy for patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome (PFPS) is common among adolescents and young adults. It is characterised by pain behind or around the patella and crepitations, provoked by ascending or descending stairs, squatting, prolonged sitting with flexed knees, running and cycling. The symptoms impede function in daily activities or sports. Pharmacological treatments focus on reducing pain symptoms (non-steroidal anti-inflammatory drugs (NSAIDs), glucocorticosteroids), or restoring the assumed underlying pathology (compounds containing glucosamine to stimulate cartilage metabolism, anabolic steroids to increase bone density of the patella and build up supporting muscles). In studies, drugs are usually applied in addition to exercises aimed at building up supporting musculature.

OBJECTIVES

This review aims to summarise the evidence of effectiveness of pharmacotherapy in reducing anterior knee pain and improving knee function in people with PFPS.

SEARCH STRATEGY

We searched the Cochrane Musculoskeletal Injuries Group and Cochrane Rehabilitation and Related Therapies Field trials registers, the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 4, 2003), PEDro (up to January 2004), MEDLINE (1966 to January 2004), EMBASE (1988 to January 2004), and CINAHL (1982 to January 2004).

SELECTION CRITERIA

Controlled trials (randomised or not) comparing pharmacotherapy with placebo, different types of pharmacotherapy, or pharmacotherapy to other therapies for people with PFPS.

DATA COLLECTION AND ANALYSIS

The literature search yielded 780 publications. Eight trials were included, of which three were of high quality. Data were analysed qualitatively using best evidence synthesis, because meta-analysis was impeded by differences in route of administration of drugs, care programs and outcome measures.

MAIN RESULTS

Four trials (163 participants) studied the effect of NSAIDs. Aspirin compared to placebo in a high quality trial produced no significant differences in clinical symptoms and signs. Naproxen produced significant short term pain reduction when compared to placebo, but not when compared to diflunisal. Laser therapy to stimulate blood flow in tender areas led to more satisfied participants than tenoxicam, though not significantly. Two high quality RCTs (84 participants) studied the effect of glycosaminoglycan polysulphate (GAGPS). Twelve intramuscular injections in six weeks led to significantly more participants with a good overall therapeutic effect after one year, and to significantly better pain reduction during one of two activities. Five weekly intra-articular injections of GAGPS and lidocaine were compared with intra-articular injections of saline and lidocaine or no injections, all with concurrent quadriceps training. Injected participants showed better function after six weeks, though only the difference between GAGPS injected participants and non-injected participants was significant. The differences had disappeared after one year. One trial (43 participants) found that intramuscular injections of the anabolic steroid nandrolone phenylpropionate significantly improved both pain and function compared to placebo injections.

REVIEWERS' CONCLUSIONS

There is only limited evidence for the effectiveness of NSAIDs for short term pain reduction in PFPS. The evidence for the effect of glycosaminoglycan polysulphate is conflicting and merits further investigation. The anabolic steroid nandrolone may be effective, but is too controversial for treatment of PFPS.

Exercise therapy for patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome (PFPS) is a common problem among adolescents and young adults, characterised by retropatellar pain (behind the kneecap) or peripatellar pain (around the kneecap) when ascending or descending stairs, squatting or sitting with flexed knees. Etiology, structures causing the pain and treatment methods are all debated in literature, but consensus has not been reached so far. Exercise therapy to strengthen the quadriceps is often prescribed, though its efficacy is still debated.

OBJECTIVES

This review aims to summarise the evidence of effectiveness of exercise therapy in reducing anterior knee pain and improving knee function in patients with PFPS.

SEARCH STRATEGY

We searched the Cochrane Musculoskeletal Injuries Group and Cochrane Rehabilitation and Related Therapies Field specialised registers, the Cochrane Controlled Trials Register, PEDro - The Physiotherapy Evidence Database, MEDLINE, EMBASE, CINAHL, up till December 2001 for controlled trials (randomised or not) comparing exercise therapy with control groups, or comparing different types of exercise therapy.

SELECTION CRITERIA

Only trials focusing on exercise therapy in patients with PFPS were considered. Trials in patients with other diagnoses such as tendinitis, Osgood Schlatter syndrome, bursitis, traumatic injuries, osteoarthritis, plica syndrome, Sinding-Larssen-Johansson syndrome and patellar luxations were excluded.

DATA COLLECTION AND ANALYSIS

From 750 publications 12 trials were selected. All included trials studied quadriceps strengthening exercises. Outcome assessments for knee pain and knee function in daily life were used in a best evidence synthesis to summarise evidence for effectiveness.

MAIN RESULTS

One high and two low quality studies used a control group not receiving exercise therapy. Significantly greater pain reduction in the exercise groups was found in one high and one low quality study, though at different time points. Only one low quality study reported significantly greater functional improvement with exercise. Five studies compared exercise therapies that could be designated closed kinetic chain exercise (foot in contact with a surface) versus open kinetic chain exercise (foot not in contact with a surface). Two of these studies were of high quality, but no significant differences in improvement of function or reduction of pain were apparent between the types of exercise in any of the studies. The remaining four studies, all of which were of low quality, focused on other treatment comparisons.

REVIEWER'S CONCLUSIONS

The evidence that exercise therapy is more effective in treating PFPS than no exercise was limited with respect to pain reduction, and conflicting with respect to functional improvement. There is strong evidence that open and closed kinetic chain exercise are equally effective. Further research to substantiate the efficacy of exercise treatment compared to a non-exercising control group is needed, and thorough consideration should be given to methodological aspects of study design and reporting.

Vastus medialis electrical stimulation to improve lower extremity function following a lateral patellar retinacular release

STUDY DESIGN

A single-case study design.

OBJECTIVES

To examine the effect of electrical stimulation of the vastus medialis muscle on stiffness, pain and function for a patient with delayed functional progress following a lateral patellar retinacular release.

BACKGROUND

Five months after an arthroscopic lateral patellar retinacular release, the patient, although highly motivated, had made little progress using routine exercises and taping.

METHODS AND MEASURES

An electrical stimulation program producing approximately 300 contractions daily of the vastus medialis muscle was implemented. The electrical stimulation applied for 33 of the 36 days was a rectangular and balanced biphasic pulse of 625-micros duration, 70-Hz frequency, 8-second peak on-time, 3-second off-time, 1-second ramp-up, and 0.5-second ramp-down. Objective measures of stair climbing and hopping, together with the subjective measure of therapist-palpated superomedial patella displacement force, were recorded for each treatment visit. Other subjective measures were the patient's daily recordings of knee pain and stiffness.

RESULTS

Patient-reported stiffness reduced rapidly as the actual and cumulative number of daily contractions of the vastus medialis muscle increased. After 8 days of electrical stimulation, the patient was able to ascend stairs unassisted and after another 21 days to hop unsupported.

CONCLUSIONS

Stiffness rapidly reduced and function started to improve once the electrical stimulation program was implemented. Recovery during the 36 days of treatment with electrical stimulation was greater than during the previous 5 months using other methods. Compliance was not an issue, nor was muscle soreness.

Orthotic devices for treating patellofemoral pain syndrome

BACKGROUND

Patellofemoral pain syndrome is a frequently reported condition in active adults. A wide variety of conservative treatment strategies have been described. As yet, no optimal strategy has been identified. Application of orthotic devices e.g. knee braces, knee straps, forms of taping of the knee, active training devices, knee sleeves and in-shoe orthotics to support the foot have been advocated to treat this condition.

OBJECTIVES

To assess the effectiveness of foot and knee orthotics for treatment of patellofemoral pain syndrome.

SEARCH STRATEGY

We searched the Cochrane Musculoskeletal Injuries Group specialised register (December 2001), the Cochrane Controlled Trials register (Issue 2, 2000), MEDLINE (January 1966 to March 2000; EMBASE (January 1988 to March 2000); CINAHL (January 1982 to March 2000) and PEDro (up to March 2000). Relevant orthotic companies were contacted.

SELECTION CRITERIA

All randomised and quasi-randomised trials comparing the effectiveness of knee or foot orthotics for treatment of patellofemoral pain syndrome were selected. Trials describing the use of orthotic devices in conjunction with operative treatment were excluded.

DATA COLLECTION AND ANALYSIS

Three reviewers independently assessed methodological quality of the identified trials by use of a modified version of the Cochrane Musculoskeletal Injuries Group assessment tool, consisting 11 items. Two reviewers extracted data without blinding. Trialists were contacted to obtain missing data.

MAIN RESULTS

Five trials involving 362 participants were included in this review. Five other trials await possible inclusion if further information can be obtained and one awaits further assessment. Due to clinical heterogeneity, we refrained from statistical pooling and conducted analysis by grading the strength of scientific evidence. The level of obtained research-based evidence was graded as limited as all trials were of low methodological quality. This limited research-based evidence showed the Protonics orthosis at six week follow-up was significantly more effective for decrease in pain (weighted mean difference (WMD) between groups 3.2; 95% confidence interval (CI) 2.8 to 3.6), functional improvement on the Kujala score (WMD 45.6; 95% CI 43.4 to 47.7) and change in patellofemoral congruence angle (WMD 17.2; 95% CI 14.1 to 20.3) when compared to no treatment. A comprehensive programme including tape application was significantly superior to a monitored exercise programme without tape application for decrease in worst pain (WMD 1.6; 95% CI 0.4 to 2.8) and usual pain (WMD 1.2; 95% CI 0.2 to 2.1), and clinical change and functional improvement questionnaire scores (WMD 10, 95% CI 2.07 to 17.93) at four weeks follow-up. The trials reported statistically significant differences in patient satisfaction after applied therapy (WMD 3.3; 95% CI 0.5 to 6.1) in favour of the McConnell regimen compared with the Coumans bandage at six weeks follow-up.

REVIEWER'S CONCLUSIONS

The evidence from randomised controlled trials is currently too limited to draw definitive conclusions about the use of knee and foot orthotics for the treatment of patellofemoral pain. Future high quality trials in this field are warranted.

Reliability of the lateral pull test and tilt test to assess patellar alignment in subjects with symptomatic knees: student raters

STUDY DESIGN

Test-retest reliability with blinded testers.

OBJECTIVES

To determine the inter- and intra-rater reliability of the lateral pull test and patellar tilt test.

BACKGROUND

If patellar malalignment can be detected by clinical examination, then condition-specific treatment interventions may be implemented in patients with patellofemoral pain syndrome. However, several clinical tests used to assess patellar mobility have recently been shown to have poor to fair reliability. Because the lateral pull test and the patellar tilt test are widely used clinically as diagnostic tests for patellofemoral pain syndrome but have not been previously tested for reliability, we examined these tests.

METHODS AND MEASURES

Fifty-two subjects (age range, 21-48 years) provided 95 knees (19 symptomatic and 76 asymptomatic) for assessment of the lateral pull test. Two testers, blinded to the presence or absence of symptoms, independently performed the lateral pull test in random order. Fifty-five subjects (age range, 22-42 years) provided 99 knees (73 asymptomatic and 26 symptomatic) for assessment of the patellar tilt test. Three blinded testers independently performed the patellar tilt test in random order. All subjects were tested and retested within 3-5 days. A kappa (kappa) statistic was used to assess the agreement of findings within each tester and between testers.

RESULTS

The kappa coefficients for intrarater reliability varied from 0.39 to 0.47 for the lateral pull test and from 0.44 to 0.50 for the patellar tilt test, while the coefficients for interrater reliability were 0.31 for the lateral pull test and varied from 0.20 to 0.35 for the tilt test.

CONCLUSIONS

Repeated lateral pull tests and patellar tilt tests had fair intrarater and poor interrater reliability. Our results suggest that care must be taken in placing too much emphasis on these tests when making clinical decisions.