Development of a clinical prediction rule for classifying patients with patellofemoral pain syndrome who respond to patellar taping

Directional preference of the extremity: a preliminary investigation

Background: Mechanical diagnosis and therapy (MDT) is a specific classification-based musculoskeletal examination and intervention system that uses repeated end range and sustained movement to classify patients into mechanical syndromes. Research has recently demonstrated increased prevalence, reliability, and efficacy of MDT syndromes in varied peripheral musculoskeletal populations. There is currently no research analyzing if predictive variables exist for establishing directional preference in peripheral joints, other than the wrist. The aim of this study was to examine the clinical application of predictive variables for establishing directional preference and spinal referral in patients with isolated peripheral joint pain. Case Description: Thirty-seven consecutive patients with isolated peripheral pain were evaluated and classified using MDT assessment. Secondary analysis of predetermined variables was performed for association with directional preference and identification of spinal referral in Derangement syndrome. Results: All 37 patients were classified using MDT assessment. Thirty-three (89.2%) were classified as Derangement syndrome: 17 as spinal Derangement (45.9%) and 16 as peripheral Derangement (43.2%). One peripheral derangement also had an underlying Articular Dysfunction. Additionally, there were four patients classified as Other (10.8%). Discussion: Historical and physical examination findings were analyzed to determine if there were associated variables of directional preference or spinal referral. Mechanical stress was found to be the most associated factor in predicting directional preference. No peripheral movement loss, paresthesia, and constant pain were more associated with spinal referral. These findings may lead to a greater understanding of peripheral MDT assessment, which may lead to increased identification of directional preference and improved patient outcomes. Level of Evidence: 4.

Treatment Success of Hip and Core or Knee Strengthening for Patellofemoral Pain: Development of Clinical Prediction Rules

CONTEXT

  Patellofemoral pain (PFP) is a common injury that interferes with quality of life and physical activity. Clinical subgroups of patients may exist, one of which is caused by proximal muscle dysfunction.

OBJECTIVES

  To develop clinical prediction rules that predict a positive outcome after either a hip and core- or knee-focused strengthening program for individuals with PFP.

DESIGN

  Secondary analysis of data from a randomized control trial.

SETTING

  Four university laboratories.

PATIENTS OR OTHER PARTICIPANTS

  A total of 199 participants with PFP.

INTERVENTION(S)

  Participants were randomly allocated to either a hip and core-focused (n = 111) or knee-focused (n = 88) rehabilitation group for a 6-week program.

MAIN OUTCOME MEASURE(S)

  Demographics, self-reported knee pain (visual analog scale) and function (Anterior Knee Pain Scale), hip strength, abdominal muscle endurance, and hip range of motion were evaluated at baseline. Treatment success was defined as a decrease in visual analog scale score by ≥2 cm or an increase in the Anterior Knee Pain Scale score by ≥8 points or both. Bivariate relationships between the outcome (treatment success) and the predictor variables were explored, followed by a forward stepwise logistic regression to predict a successful outcome.

RESULTS

  Patients with more pain, better function, greater lateral core endurance, and less anterior core endurance were more likely to have a successful outcome after hip and core strengthening (88% sensitivity and 54% specificity). Patients with lower weight, weaker hip internal rotation, stronger hip extension, and greater trunk-extension endurance were more likely to have success after knee strengthening (82% sensitivity and 58% specificity).

CONCLUSION

  The patients with PFP who have more baseline pain and yet maintain a high level of function may experience additional benefit from hip and core strengthening. The clinical prediction rules from this study remain in the developmental phase and should be applied with caution until externally validated.

Reliability of physical examination tests for the diagnosis of knee disorders: Evidence from a systematic review

Clinicians often rely on physical examination tests to guide them in the diagnostic process of knee disorders. However, reliability of these tests is often overlooked and may influence the consistency of results and overall diagnostic validity. Therefore, the objective of this study was to systematically review evidence on the reliability of physical examination tests for the diagnosis of knee disorders. A structured literature search was conducted in databases up to January 2016. Included studies needed to report reliability measures of at least one physical test for any knee disorder. Methodological quality was evaluated using the QAREL checklist. A qualitative synthesis of the evidence was performed. Thirty-three studies were included with a mean QAREL score of 5.5 ± 0.5. Based on low to moderate quality evidence, the Thessaly test for meniscal injuries reached moderate inter-rater reliability (k = 0.54). Based on moderate to excellent quality evidence, the Lachman for anterior cruciate ligament injuries reached moderate to excellent inter-rater reliability (k = 0.42 to 0.81). Based on low to moderate quality evidence, the Tibiofemoral Crepitus, Joint Line and Patellofemoral Pain/Tenderness, Bony Enlargement and Joint Pain on Movement tests for knee osteoarthritis reached fair to excellent inter-rater reliability (k = 0.29 to 0.93). Based on low to moderate quality evidence, the Lateral Glide, Lateral Tilt, Lateral Pull and Quality of Movement tests for patellofemoral pain reached moderate to good inter-rater reliability (k = 0.49 to 0.73). Many physical tests appear to reach good inter-rater reliability, but this is based on low-quality and conflicting evidence. High-quality research is required to evaluate the reliability of knee physical examination tests.

Clinical Decision Support Tools for Selecting Interventions for Patients with Disabling Musculoskeletal Disorders: A Scoping Review

Purpose We aimed to identify and inventory clinical decision support (CDS) tools for helping front-line staff select interventions for patients with musculoskeletal (MSK) disorders. Methods We used Arksey and O'Malley's scoping review framework which progresses through five stages: (1) identifying the research question; (2) identifying relevant studies; (3) selecting studies for analysis; (4) charting the data; and (5) collating, summarizing and reporting results. We considered computer-based, and other available tools, such as algorithms, care pathways, rules and models. Since this research crosses multiple disciplines, we searched health care, computing science and business databases. Results Our search resulted in 4605 manuscripts. Titles and abstracts were screened for relevance. The reliability of the screening process was high with an average percentage of agreement of 92.3 %. Of the located articles, 123 were considered relevant. Within this literature, there were 43 CDS tools located. These were classified into 3 main areas: computer-based tools/questionnaires (n = 8, 19 %), treatment algorithms/models (n = 14, 33 %), and clinical prediction rules/classification systems (n = 21, 49 %). Each of these areas and the associated evidence are described. The state of evidentiary support for CDS tools is still preliminary and lacks external validation, head-to-head comparisons, or evidence of generalizability across different populations and settings. Conclusions CDS tools, especially those employing rapidly advancing computer technologies, are under development and of potential interest to health care providers, case management organizations and funders of care. Based on the results of this scoping review, we conclude that these tools, models and systems should be subjected to further validation before they can be recommended for large-scale implementation for managing patients with MSK disorders.

Predictors of treatment response to strengthening and stretching exercises for patellofemoral pain: An examination of patellar alignment

BACKGROUND

Closed kinetic chain and quadriceps strengthening, combined with flexibility exercises of the lower limb musculature, is a common treatment for patellofemoral pain syndrome (PFPS). The effectiveness has been well documented; however, very little is known about which factors predict treatment success.

METHODS

A total of 43 female subjects with PFPS participated in an eight-week progressive leg press (LP) strengthening and stretching exercise program. A decrease of 1.5 cm on a 10 cm visual analog scale (VAS) score was used as an indicator for treatment success. The baseline patellar tilt angle difference (PTA-d) due to quadriceps contraction prior to treatment was evaluated as a predictor of treatment success. The logistic regression and receiver operating characteristics (ROC) curve analysis were performed to investigate the predictive value of PTA-d.

RESULTS

PTA-d could significantly predict the treatment success of LP strengthening and stretching exercises. The odds ratio (OR) for having an unsuccessful outcome was 1.19 (95% confidence interval (CI), 1.03-1.39, P<0.021) per degree increment of PTA-d. The most optimal cut-off value for the clinical discrimination of treatment success after LP strengthening and stretching exercise was -1.5° of PTA-d (sensitivity=0.74, specificity=0.71). The area under the ROC curve was 0.73 (standard error=0.08).

CONCLUSIONS

Female patients with PFPS whose quadriceps contraction reduced the lateral patellar tilt prior to LP strengthening and stretching exercise treatment are more likely to experience pain relief. It seems clinically important to check dynamic patellar tilt characteristics before treatment to aid in clinical decision making.

A review of knee pain in adolescent females

Primary care practitioners are in a position to educate patients and parents about the risk factors that may increase the incidence of knee pain in adolescent females. This article highlights patellofemoral pain syndrome, Sinding-Larsen-Johansson syndrome, Osgood-Schlatter disease, and meniscal tears.

Predictors for identifying patients with patellofemoral pain syndrome responding to femoral nerve mobilization

OBJECTIVE

To identify the predictors for successful neurodynamic management in patients with patellofemoral pain syndrome.

DESIGN

Prospective cohort, prediction rule study.

SETTING

Hospital.

PARTICIPANTS

Patients with patellofemoral pain syndrome (N=51) underwent clinical examination and measurement of physical parameters, including femoral slump test, lower-extremity alignment, flexibility and muscle strength, and functional level.

INTERVENTION

Patients received 6 treatment sessions of femoral nerve mobilization within 2 weeks.

MAIN OUTCOME MEASURES

Pain level during functional testing was assessed before and after the first and sixth session of treatment. Patients were then grouped into responder and nonresponder groups. Criteria for the responder group was a pain score decrease ≥50% or Global Rating Scale score ≥4. Chi-square and independent t tests were used to identify potential variables with a significance level of .10, and stepwise logistic regression was used to find predictors with a significance level of .05.

RESULTS

Twenty-five patients responded to the initial treatment (immediate effect), and 28 patients responded after 6 sessions (longer-term effect). A positive femoral slump test was identified as the predictor for the immediate treatment effect. The prediction factors for the longer-term effect included responding to femoral nerve mobilization the first time and a bilateral difference in hip extension angles. Application of the clinical predictors improved the success rate to 90% for 1 treatment session and 93% for 6 treatment sessions.

CONCLUSIONS

Clinicians could use the positive femoral slump test and a bilateral difference in hip extension angles during the femoral slump test to determine whether or not patients with patellofemoral pain syndrome might benefit from femoral nerve mobilization.

Predictors of non-use of prostheses by people with lower limb amputation after discharge from rehabilitation: development and validation of clinical prediction rules

QUESTIONS

Can rules be developed to predict the risk of non-use of prostheses by people with lower limb amputation following discharge from rehabilitation? Are these clinical prediction rules valid?

DESIGN

Retrospective and prospective cohort study designs.

PARTICIPANTS

Consecutive tertiary rehabilitation patients: 135 retrospective (103 males, mean age = 56 years, SD 15) and 66 prospective (58 males, mean age = 54 years, SD 16).

METHOD

Medical records were audited for potential predictor variables. Retrospective participants were interviewed at a median of 1.9 years after discharge (IQR 1.4 to 2.5) and prospective participants at a median of 1.3 years (IQR 1.1 to 1.4).

RESULTS

Clinical prediction rules were identified at 4, 8 and 12 months after discharge, and validated. Amputation levels above transtibial and mobility-aid use were common predictors for all three time frames. At 4 months, if four out of five predictor variables were present (LR+ = 43.9, 95% CI 2.73 to 999+), the probability of non-use increased from 12 to 86% (p<0.001). At 8 months, if all three predictor variables were present (LR+ = 33.9, 95% CI 2.1 to 999+), the probability of non-use increased from 15 to 86% (p<0.001). At 12 months, if two out of three predictor variables were present (LR+=2.8, 95% CI 0.9 to 6.6), the probability of non-use increased from 17 to 36% (p<0.031).

CONCLUSIONS

These validated clinical prediction rules have implications for rehabilitation and service model development. [Roffman CE, Buchanan J, Allison GT (2014) Predictors of non-use of prostheses by people with lower limb amputation after discharge from rehabilitation: development and validation of clinical prediction rules.Journal of Physiotherapy60: 224-231].

Cohort study design: an underutilized approach for advancement of evidence-based and patient-centered practice in athletic training

OBJECTIVE

Providing patient-centered care requires consideration of numerous factors when making decisions that will influence a patient's health status.

BACKGROUND

Clinical decisions should be informed by relevant research evidence, but the literature often lacks pertinent information for problems encountered in routine clinical practice. Although a randomized clinical trial provides the best research design to ensure the internal validity of study findings, ethical considerations and the competitive culture of sport often preclude random assignment of patients or participants to a control condition.

CLINICAL ADVANTAGES

A cohort study design and Bayesian approach to data analysis can provide valuable evidence to support clinical decisions. Dichotomous classification of both an outcome and 1 or more predictive factors permits quantification of the likelihood of occurrence of a specified outcome.

CONCLUSIONS

Multifactorial prediction models can reduce uncertainty in clinical decision making and facilitate the individualization of treatment, thereby supporting delivery of clinical services that are both evidence based and patient centered.

Lumbopelvic manipulation in patients with patellofemoral pain syndrome

OBJECTIVES

A recent clinical prediction rule (CPR) identified characteristics that may predict an immediate reduction in pain following lumbopelvic manipulation in patients with patellofemoral pain syndrome. The purpose of this single-arm cohort study was to replicate the proposed CPR in a different population and investigate changes in self-reported pain, hip range of motion, strength, and function immediately following lumbopelvic manipulation.

METHODS

Forty-four subjects (63·6% female; mean age 27·4 years) met inclusion criteria. Hip internal rotation range of motion, lower extremity strength using a handheld dynamometer, and single/triple hop tests were assessed prior to and immediately following a spinal manipulation. A global rating of change questionnaire was administered after testing and telephonically at 1 week. Paired t-tests compared pre- and post-manipulation range of motion, strength, and hop test limb symmetry indices (α = 0·05).

RESULTS

Fifty-seven percent of subjects had a successful outcome measured by the numerical pain rating scale immediately following manipulation. Twenty-five of subjects experienced a successful outcome as measured by the global rating of change questionnaire at 1 week. No single individual or combination of predictor variables predicted a positive outcome immediately following the lumbopelvic manipulation (+likelihood ratio 0·7 with three of five predictor variables present). Statistically significant differences (P<0·05) were found in hip extension and abduction strength and hip internal rotation symmetry post-manipulation, but do not appear to be clinically meaningful.

DISCUSSION

The previously identified CPR was not able to be replicated and no clinically meaningful changes in range of motion, strength, or function were apparent. Future research should focus on a comprehensive impairment-based treatment approach in patients with patellofemoral pain syndrome.

Preliminary state of development of prediction models for primary care physical therapy: a systematic review

OBJECTIVE

To summarize the methodological quality and developmental stage of prediction models for musculoskeletal complaints that are relevant for physical therapists in primary care.

STUDY DESIGN AND SETTING

A systematic literature search was carried out in the databases of Medline, Embase, and Cinahl. Studies on prediction models for musculoskeletal complaints that can be used by primary care physical therapists were included. Methodological quality of the studies was assessed and relevant study characteristics were extracted.

RESULTS

The search retrieved 4,702 references of which 29 studies were included in this review. The study quality of the included studies showed substantial variation. The studied populations consisted mostly of back (n=10) and neck pain (n=6) patients, and patients with knee complaints (n=4). Most studies (n=22) used "perceived recovery" as primary outcome. Most prediction models (n=18) were at the derivation level of development.

CONCLUSIONS

Many prediction models are available for a wide range of patient populations. The developmental stage of most models is preliminary and the study quality is often moderate. We do not recommend physiotherapist to use these models yet. All models reviewed here are in the developmental stage and need validation and impact evaluation before using them in daily practice.

Early intervention for adolescents with patellofemoral pain syndrome--a pragmatic cluster randomised controlled trial

Background

Self-reported knee pain is highly prevalent among adolescents. As much as 50% of the non-specific knee pain may be attributed to Patellofemoral Pain Syndrome (PFPS). In the short term, exercise therapy appears to have a better effect than patient education consisting of written information and general advice on exercise or compared with placebo treatment. But the long-term effect of exercise therapy compared with patient education is conflicting. The purpose of this study is to examine the short- and long-term effectiveness of patient education compared with patient education and multimodal physiotherapy applied at a very early stage of the condition among adolescents.

Methods/Design

This study is a single blind pragmatic cluster randomised controlled trial. Four upper secondary schools have been invited to participate in the study (approximately 2500 students, aged 15-19 years). Students are asked to answer an online questionnaire regarding musculoskeletal pain. The students who report knee pain are contacted by telephone and offered a clinical examination by a rheumatologist. Subjects who fit the inclusion criteria and are diagnosed with PFPS are invited to participate in the study. A minimum of 102 students with PFPS are then cluster-randomised into two intervention groups based on which school they attend. Both intervention groups receive written information and education. In addition to patient education, one group receives multimodal physiotherapy consisting primarily of neuromuscular training of the muscles around the foot, knee and hip and home exercises.

The students with PFPS fill out self-reported questionnaires at baseline, 3, 6, 12 and 24 months after inclusion in the study. The primary outcome measure is perception of recovery measured on a 7-point Likert scale ranging from "completely recovered" to "worse than ever" at 12 months.

Discussion

This study is designed to investigate the effectiveness of patient education compared with patient education combined with multimodal physiotherapy. If patient education and multimodal physiotherapy applied at an early stage of Patellofemoral Pain Syndrome proves effective, it may serve as a basis for optimising the clinical pathway for those suffering from the condition, where specific emphasis can be placed on early diagnosis and early treatment.

Trial Registration

clinicaltrials.gov reference: NCT01438762

Lumbopelvic joint manipulation and quadriceps activation of people with patellofemoral pain syndrome

CONTEXT

Quadriceps weakness and inhibition are impairments associated with patellofemoral pain syndrome (PFPS). Lumbopelvic joint manipulation has been shown to improve quadriceps force output and inhibition, but the duration of the effect is unknown.

OBJECTIVE

To determine whether quadriceps strength and activation are increased and maintained for 1 hour after high-grade or low-grade joint mobilization or manipulation applied at the lumbopelvic region in people with PFPS.

DESIGN

Randomized controlled clinical trial.

SETTING

University laboratory.

PATIENTS OR OTHER PARTICIPANTS

Forty-eight people with PFPS (age = 24.6 ± 8.9 years, height = 174.3 ± 11.2 cm, mass = 78.4 ± 16.8 kg) participated.

INTERVENTION(S)

Participants were randomized to 1 of 3 groups: lumbopelvic joint manipulation (grade V), side-lying lumbar midrange flexion and extension passive range of motion (grade II) for 1 minute, or prone extension on the elbows for 3 minutes.

MAIN OUTCOME MEASURE(S)

Quadriceps force and activation were measured using the burst superimposition technique during a seated isometric knee extension task. A 2-way repeated-measures analysis of variance was performed to compare changes in quadriceps force and activation among groups over time (before intervention and at 0, 20, 40, and 60 minutes after intervention).

RESULTS

We found no differences in quadriceps force output (F(5.33,101.18) = 0.65, P = .67) or central activation ratio (F(4.84,92.03) = 0.38, P = .86) values among groups after intervention. When groups were pooled, we found differences across time for quadriceps force (F(2.66,101.18) = 5.03, P = .004) and activation (F(2.42,92.03) = 3.85, P = .02). Quadriceps force was not different at 0 minutes after intervention (t(40) = 1.68, P = .10), but it decreased at 20 (t(40) = 2.16, P = .04), 40 (t(40) = 2.87, P = .01) and 60 (t(40) = 3.04, P = .004) minutes after intervention. All groups demonstrated decreased quadriceps activation at 0 minutes after intervention (t(40) = 4.17, P < .001), but subsequent measures were not different from preintervention levels (t(40) range, 1.53-1.83, P > .09).

CONCLUSIONS

Interventions directed at the lumbopelvic region did not have immediate effects on quadriceps force output or activation. Muscle fatigue might have contributed to decreased force output and activation over 1 hour of testing.

Critical appraisal of clinical prediction rules that aim to optimize treatment selection for musculoskeletal conditions

BACKGROUND

Clinical prediction rules (CPRs) for treatment selection in musculoskeletal conditions have become increasingly popular.

PURPOSE

The purposes of this review are: (1) to critically appraise studies evaluating CPRs and (2) to consider the clinical utility and stage of development of each CPR.

DATA SOURCES

Pertinent databases were searched up to April 2009. Studies aiming to develop or evaluate a CPR for treatment response in musculoskeletal conditions were included. Two independent reviewers assessed eligibility and extracted methodological data, stage of development, and effect size information. STUDY SELECTION/DATA EXTRACTION AND SYNTHESIS: Eighteen studies, evaluating 15 separate CPRs, were included. Fourteen CPRs were at the derivation stage, and all CPRs had been evaluated using a single-arm trial design, thus it is not possible to determine whether the CPRs identify prognosis (regardless of treatment) or specifically response to treatment. The CPR at the validation stage investigated spinal manipulative therapy (SMT) for low back pain and had been evaluated in 2 separate well-conducted randomized controlled trials. The first trial demonstrated a clinically meaningful effect of the SMT CPR; the additional effect from SMT in patients "positive-on-the-rule" was 15 Oswestry disability units at week 1 and 9 units at week 4. The second trial showed that the CPR did not generalize to a different clinical setting, including a modified treatment.

LIMITATIONS

Due to differences in methods of reporting and journal publication restraints (eg, word count restrictions), some quality assessment items may have been completed in the included studies, but not captured in this review.

CONCLUSIONS

There is, at present, little evidence that CPRs can be used to predict effects of treatment for musculoskeletal conditions. The principal problem is that most studies use designs that cannot differentiate between predictors of response to treatment and general predictors of outcome. Only 1 CPR has been evaluated within an RCT designed to predict response to treatment. Validation of these rules is imperative to allow clinical application.

McConnell taping shifts the patella inferiorly in patients with patellofemoral pain: a dynamic magnetic resonance imaging study

BACKGROUND

Patellar taping is widely used clinically to treat patients with patellofemoral pain syndrome (PFPS). Although patellar taping has been demonstrated to reduce patellofemoral pain in patients with PFPS, the kinematic source for this pain reduction has not been identified.

OBJECTIVE

The purpose of this study was to quantify the changes in the 6-degrees-of-freedom patellofemoral kinematics due to taping in patients with PFPS.

DESIGN

A within-subject design and a sample of convenience were used.

PARTICIPANTS

Fourteen volunteers (19 knees) who were diagnosed with patellofemoral pain that was present for a year or longer were included. Each knee had to meet at least 1 of the following inclusion criteria: Q-angle of > or =15 degrees, a positive apprehension test, patellar lateral hypermobility (> or =10 mm), or a positive "J sign."

METHODS

Each knee underwent 2 randomly ordered testing conditions (untaped and taped). A full fast-phase contrast (PC) magnetic resonance image set was acquired for each condition while the participants volitionally extended and flexed their knee. Three-dimensional displacements and rotations were calculated through integration of the fast-PC velocity data. Statistical comparisons between baseline patellofemoral kinematics and the change in kinematics due to taping were performed using a 2-tailed paired Student t test. Correlations between baseline patellofemoral kinematics and the change in kinematics due to taping also were quantified.

RESULTS

Patellar taping resulted in a significant patellofemoral inferior shift. The strongest correlation existed between the change in lateral-medial displacement with taping and baseline (r=-.60).

CONCLUSIONS

The inferior shift in patellar displacement with taping partially explains the previously documented decrease in pain due to increases in contact area. The lack of alteration in 5 of the 6 kinematic variables with taping may have been due to the fact that post-taping kinematic alterations are sensitive to the baseline kinematic values.

Concurrent criterion-related validity and reliability of a clinical test to measure femoral anteversion

STUDY DESIGN

Clinical measurement, criterion standard.

OBJECTIVES

To determine if the clinical measure of femoral anteversion is comparable to measures obtained from magnetic resonance imaging (MRI). An additional purpose of this study was to assess the intertester and intratester reliability of the clinical test.

BACKGROUND

Femoral anteversion is commonly assessed as part of the physical examination; however, limited and inconsistent data exist on the validity and reliability of the clinical test.

METHODS

Eighteen healthy adults (9 males, 9 females; mean +/- SD age, 25.4 +/- 3.3 years; body mass index, 22.9 +/- 3.4 kg/m2) participated. Each underwent 3 data collection sessions: (1) MRI to measure femoral anteversion, (2) clinical testing of femoral anteversion, measured independently by 2 physical therapists, and (3) repeated clinical testing. Validity and reliability were assessed using intraclass correlation coefficient (ICC2,3) and standard error of measurement (SEM).

RESULTS

Moderate agreement was found between the clinical test and MRI measures of femoral anteversion (ICCs of 0.69 and 0.67 for examiners 1 and 2, respectively). The SEM was similar for both examiners (5.8 degrees and 6.0 degrees ). Both intra tester (ICCs of 0.88 and 0.90 for examiners 1 and 2, respectively) and intertester (ICC = 0.83) reliability was found to be substantial.

CONCLUSIONS

In persons with a low body mass index, the clinical test to assess femoral anteversion was shown to exhibit substantial reliability, but only moderate agreement with MRI measurements. When performing the clinical test, one can be 95% confident that the true value of femoral anteversion will fall within 11.8 degrees of the clinically measured value. This relatively wide confidence interval calls into question the clinical utility of the clinical test for assessing femoral anteversion.

Understanding patellofemoral pain with maltracking in the presence of joint laxity: complete 3D in vivo patellofemoral and tibiofemoral kinematics

Patellofemoral pain is widely accepted as one of the most common pathologies involving the knee, yet the etiology of this pain is still an open debate. Generalized joint laxity has been associated with patellofemoral pain, but is not often discussed as a potential source of patellar maltracking. Thus, the objective of this study was to compare the complete 6 degree of freedom patellofemoral and tibiofemoral kinematics from a group of patients diagnosed with patellofemoral pain syndrome and maltracking to those from an asymptomatic population. The following null hypotheses were tested: kinematic alterations in patellofemoral maltracking are limited to the axial plane; knee joint kinematics are the same in maltrackers with and without generalized joint laxity (defined by a clinical diagnosis of Ehlers Danlos Syndrome); and no correlations exist between tibiofemoral and patellofemoral kinematics or within patellofemoral kinematics. This study demonstrated that alterations in patellofemoral kinematics, associated with patellofemoral pain, are not limited to the axial plane, minimal correlations exist between patellofemoral and tibiofemoral kinematics, and distinct subgroups likely exist within the general population of maltrackers. Being able to identify subgroups correctly within the omnibus diagnosis of patellar maltracking is a crucial step in correctly defining the pathophysiology and the eventual treatment of these patients.

Clinical prediction rules for physical therapy interventions: a systematic review

BACKGROUND AND PURPOSE

Clinical prediction rules (CPRs) involving physical therapy interventions have been published recently. The quality of the studies used to develop the CPRs was not previously considered, a fact that has potential implications for clinical applications and future research. The purpose of this systematic review was to determine the quality of published CPRs developed for physical therapy interventions.

METHODS

Relevant databases were searched up to June 2008. Studies were included in this review if the explicit purpose was to develop a CPR for conditions commonly treated by physical therapists. Validated CPRs were excluded from this review. Study quality was independently determined by 3 reviewers using standard 18-item criteria for assessing the methodological quality of prognostic studies. Percentage of agreement was calculated for each criterion, and the intraclass correlation coefficient (ICC) was determined for overall quality scores.

RESULTS

Ten studies met the inclusion criteria and were included in this review. Percentage of agreement for individual criteria ranged from 90% to 100%, and the ICC for the overall quality score was .73 (95% confidence interval=.27-.92). Criteria commonly not met were adequate description of inclusion or exclusion criteria, inclusion of an inception cohort, adequate follow-up, masked assessments, sufficient sample sizes, and assessments of potential psychosocial factors. Quality scores for individual studies ranged from 48.2% to 74.0%.

DISCUSSION AND CONCLUSION

Validation studies are rarely reported in the literature; therefore, CPRs derived from high-quality studies may have the best potential for use in clinical settings. Investigators planning future studies of physical therapy CPRs should consider including inception cohorts, using longer follow-up times, performing masked assessments, recruiting larger sample sizes, and incorporating psychological and psychosocial assessments.

Knee osteoarthritis: primary care using noninvasive devices and biomechanical principles

Osteoarthritis (OA) is an epidemic for which there is no known cure. There is enormous popular demand for noninvasive and nonpharmacologic therapies for OA, and there is a pressing need for primary care physicians to respond by updating their pattern of practice. Despite increasing concern about the capacity of our health care system to meet rising demands, routine primary care for knee OA has changed little over several decades. This article introduces physicians to many of the most important noninvasive devices used in the conservative management of symptomatic knee OA.

Management of patients with patellofemoral pain syndrome using a multimodal approach: a case series

STUDY DESIGN

A case series of consecutive patients referred to physical therapy with patellofemoral pain syndrome (PFPS).

BACKGROUND

Physical therapists often treat patients with PFPS, yet there is currently no consensus as to the most effective management strategies. The purpose of this case series is to describe the outcomes of patients referred to physical therapy with PFPS who were treated with a multimodal approach.

CASE DESCRIPTION

Five patients were treated with a combination of thrust and nonthrust manipulation directed at the joints of the lower quarter, trunk and hip stabilization exercises, patellar taping, and foot orthotics. Outcome measures used to capture change in patient status included the Numeric Pain Rating Scale, the Kujala Anterior Knee Pain Scale, the Lower Extremity Functional Scale, and the Global Rating of Change.

OUTCOMES

Five patients (median age, 15 years; range, 14-50 years) with a median duration of knee pain for 8 months (range, 3-24 months) were included in this prospective case series. Four (80%) of the 5 patients demonstrated decreased pain and a clinically significant improvement in function. These gains in function were maintained at a 6-month follow-up.

DISCUSSION

Although a cause-and-effect relationship cannot be inferred from a case series, the outcomes achieved by the patients are consistent with studies incorporating manual physical therapy, exercise, patellar taping, and orthotic prescription to the management of conditions of the lower extremity. Further randomized controlled trials should be performed to determine the effectiveness of this multimodal approach for the management of individuals with PFPS.

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.

Lumbopelvic manipulation for the treatment of patients with patellofemoral pain syndrome: development of a clinical prediction rule

STUDY DESIGN

Prospective cohort/predictive validity study.

OBJECTIVE

To determine the predictive validity of selected clinical exam items and to develop a clinical prediction rule (CPR) to determine which patients with patellofemoral pain syndrome (PFPS) have a positive immediate response to lumbopelvic manipulation.

BACKGROUND

Quadriceps muscle function in patients with PFPS was recently shown to improve following treatment with lumbopelvic manipulation. No previous study has determined if individuals with PFPS experience symptomatic relief of activity-related pain immediately following this manipulation technique.

METHODS AND MEASURES

Fifty subjects (26 male, 24 female; age range, 18-45 years) with PFPS underwent a standardized history and physical examination. After the evaluation, each subject performed 3 typically pain-producing functional activities (squatting, stepping up a 20-cm step, and stepping down a 20-cm step). The pain level perceived during each activity was rated on a numerical pain scale (0 representing no pain and 10 the worst possible pain). Following the assessment, all subjects were treated with a lumbopelvic manipulation, which was immediately followed by retesting the 3 functional activities to determine if there was any change in pain ratings. An immediate overall 50% or greater reduction in pain, or moderate or greater improvement on a global rating of change questionnaire, was considered a treatment success. Likelihood ratios (LRs) were calculated to determine which examination items were most predictive of treatment outcome.

RESULTS

Data for 49 subjects were included in the data analysis, of which 22 (45%) had a successful outcome. Five predictor variables were identified. The most powerful predictor of treatment success was a side-to-side difference in hip internal rotation range of motion greater than 14 masculine (+LR, 4.9). If this variable was present, the chance of experiencing a successful outcome improved from 45% to 80%.

CONCLUSION

A CPR was developed to predict an immediate successful response to lumbopelvic manipulation in patients with PFPS. However, in light of a limited sample size and omission of potentially meaningful predictor variables, future studies are necessary to validate the CPR.

Patellofemoral Pain

Patellofemoral pain is an extremely common disorder, especially in female athletes. There is, however, no true consensus as to the cause and appropriate treatment for patellofemoral pain. This article reviews the epidemiology of patellofemoral pain as well as the proposed etiologies, including quadriceps dysfunction, static alignment disorders, and dynamic alignment disorders. The article also reviews both conservative and surgical treatment of patellofemoral pain.

The measurement of patellar alignment in patellofemoral pain syndrome: are we confusing assumptions with evidence?

Patellofemoral pain syndrome is one of the most common orthopaedic complaints presenting to physical therapists. Although its etiology is uncertain, the cause is most often considered to be malalignment or lateral tracking of the patella. Consequently, measurement of patellar alignment has come to be accepted as an integral part of the examination of patellofemoral pain syndrome. Various measurement techniques exist, both clinical and radiological, and these have been frequently used in the diagnosis and treatment of the condition. As a corollary, the widespread use of such measurements has also lent weight to the theory that patellar malalignment is one of the primary causes of patellofemorai pain syndrome. However, an analysis of the literature reveals that the vast majority of these measurement procedures lack the appropriate scientific qualities to be considered acceptable measurement tools, including questionable reliability and validity, and an absence of appropriate normative data and a gold standard. This paper assesses the evidence for the usefulness of the most commonly used measures of patellar alignment and concludes that many of the beliefs of the clinical community with regard to the existence and measurement of patellar malalignment in patellofemoral pain syndrome may be based largely on assumptions and not on evidence.