The diagnostic value of the Clarke sign in assessing chondromalacia patella

Treatment of anterior knee pain due to chondromalacia patellae with platelet-rich plasma and hyaluronic acid in young and middle-aged adults, a cohort study

INTRODUCTION

Anterior knee pain commonly affects young women resulting in the declination of the quality of life. One of the possible pathologies causing this symptom is chondromalacia patellae (CMP). Although CMP is used to describe the softening of patellar articular cartilage, it remains a general descriptive term as it cannot be associated with a specific pathophysiologic mechanism. The objective of this study is to investigate the effect of injectable PRP on patients with anterior knee pain in absence of altered patellofemoral joint anatomy.

METHODS

For this purpose, 43 patients of the affected population were recruited to participate in this non-randomized controlled trial, 28 patients in the injection group and 15 in the only-physiotherapy group. While patients in the experimental group received three PRP injections and one injection of hyaluronic acid (HA), comparators received the standard physical therapy regimen. The treatment choice was based on patients own decree. Patients between the ages of 18 to 50 years with anterior knee pain and positive Clarke´s sign were eligible for inclusion. Patients with evident anatomical abnormalities, chronic conditions affecting the knee and severe symptoms such as blocking, were excluded from the study. Patient related measures (PROMS) in the form of the VAS and the Kujala scores were the main outcome of interest. All outcomes were measured at baseline, and after 3 and 6 months after the treatment.

RESULTS

Although an improvement was seen in both groups, a statistically significant difference favoring the injection of PRP over the physiotherapy-only group was observed (p < 0.001). The superiority of the therapeutic modality under investigation was observed at 3 and 6 months after the initial diagnosis was made. Furthermore, the results of this study revealed a significant improvement at 3 and 6 months when compared to baseline measures. The analysis of the patients age showed a negative correlation when baseline values were compared to measures at 3 and 6 months, meaning younger patients had more benefit from the treatment.

DISCUSSION

The main results of this study affirm the positive effects of PRP and HA for the treatment of anterior knee pain described by previous research and the subsequent improvement of the quality of life. Relatively little information was found in the literature search regarding the therapeutic effects of PRP on anterior knee pain and chondropathies. While a previous radiologic study found no evidence regarding the effect of PRP, this study found a benefit when comparing PROMs between patient groups.

Physiopathology of patello-femoral osteoarthritis: current concepts

Patellofemoral osteoarthritis (PFOA) is the result of degeneration and loss of articular cartilage of the patella and trochlea, and is a common cause of anterior knee pain. PFOA is triggered by insufficient adaptation to overload of the articular cartilage of the PF joint created by abnormal biomechanics. It is important to understand the pathophysiology and natural history to make the diagnosis and to plan treatment. Innate factors including malalignment, patellar instability, kinematic disorders, and acquired factors like trauma, obesity, and endocrine diseases have been found to be causes of PFOA. Genetic predisposition is also described as a contributing cause but without much scientific evidence. The diagnosis will be based on clinical manifestations, such as anterior knee pain aggravated by overloading activities, identification of risk factors, and exclusion of referred pain from other pathologies, followed by a systematic and structured physical examination. Imaging will be useful for assessing the presence of early osteoarthritis in the other compartments, for classification of the PFOA, and to identify features to establish an adequate treatment. This paper discusses varying management options for different causes of patellofemoral disease and explains the complexity of the PF joint and its often poorly understood biomechanics.

Clinical value of questionnaires & physical tests for patellofemoral pain: Validity, reliability and predictive capacity

OBJECTIVES

To determine the most appropriate method of functional assessment for "patellofemoral pain" (PFP)/"chondromalacia patella" for its diagnostic value, (validity, reliability, sensitivity, specificity, predictive value and clinical applicability); to outline initial interpretations of the questionnaires and their appropriateness, through the cut-off points determined in their scores based on physical test and Magnetic Resonance Imaging (MRI); to establish which methods should be used in conjunction with each other to obtain clinical diagnoses that are robust effective and efficient.

METHODS

(1)Intra- and inter-observer reliability and of the relationship among PFP questionnaires/physical tests validated. (2)Predictive capacity of the questionnaires. Subject: 113 knees with PFP, assessed using "Knee-injury-and-Osteoarthritis Outcome-Score-for-Patellofemoral-pain-and-osteoarthritis" (KOOS-PF), "Kujala-Patellofemoral-Score" (KPS), "Victorian-Institute-of-Sports-Assessment-for-Patellar-tendons-questionnaire" (VISA-P), and the physical tests: "patellar-palpation", "patellar-tilt", "patellar-apprehension", "Clarke" and "squat".

RESULTS

Questionnaires correlations themselves was 0.78

CONCLUSIONS

KOOS-PF, KPS and VISA-P demonstrated their diagnostic value in PFP/chondromalacia (validity, reliability, sensitivity, specificity, predictive value and clinical applicability). KOOS-PF was the most versatile, and the most appropriate in mild cases and for early detection and prevention. Squat was the best due to its reliability and clinical relationship with the questionnaires, which predicted it correctly. The functional assessment tools discussed should be applied by combining them with each other.

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MESH Headings

• Humans
• Patellofemoral Pain Syndrome
• Reproducibility of Results
• Cartilage Diseases
• Osteoarthritis
• Surveys and Questionnaires
• Patellofemoral Joint

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Affiliation(s)

Gema Chamorro-Moriana Department of Physiotherapy, Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, Seville, Spain Research Group “Area of Physiotherapy CTS305”, Spain
Fernando Espuny-Ruiz Department of Physiotherapy, Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, Seville, Spain
Carmen Ridao-Fernández Department of Physiotherapy, Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, Seville, Spain Research Group “Area of Physiotherapy CTS305”, Spain
Eleonora Magni Department of Nursing, Faculty of Nursing, Physiotherapy and Podiatry, University of Seville, Seville, Spain

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Activation, strength, and resistance: Which variables predict the kinematics of women with and without patellofemoral pain?

INTRODUCTION

Investigating the possible relationship between neuromuscular changes and movement alterations could help to describe the mechanisms underlying patellofemoral pain (PFP).

OBJECTIVE

To investigate whether activation and muscle strength of the trunk and lower limb and muscle resistance of the trunk predict the knee frontal and trunk sagittal kinematics in women with and without PFP.

METHOD

Sixty women (PFP, n = 30; asymptomatic, n = 30) underwent the single-leg squat test to collect electromyographic and kinematic data. Activation of transversus abdominis/internal oblique, gluteus medius (GMed), and vastus medialis oblique (VMO); knee frontal and trunk sagittal angles were analyzed. Participants also underwent maximal isometric tests to determine lateral trunk, hip abductor, and knee extensor torques and performed a lateral trunk resistance test. Multiple regression was used to determine predictive models.

RESULTS

In the PFP group, knee frontal angle (R2 = 0.39, p = 0.001) was predicted by GMed activation (β = 0.23, p = 0.000) and hip abductor torque (β = 0.08, p = 0.022). No variable was able to predict trunk sagittal kinematics in this group. In the asymptomatics, knee frontal angle (R2 = 0.16, p = 0.029) was predicted by hip abductor torque (β = 0.07, p = 0.029), while trunk sagittal angle (R2 = 0.24, p = 0.024) was predicted by VMO activation (β = 0.12, p = 0.016).

CONCLUSION

Kinematics is predicted by the muscles acting in the respective planes, such that hip abductors capacities are related to the knee frontal alignment in both groups, and that of the VMO is related to the trunk sagittal alignment only in asymptomatic women.

The association between patellofemoral grind and synovitis in knee osteoarthritis: data from the osteoarthritis initiative

Objective

Patellofemoral grind refers to the tender behind the knee cap while contracting the quadriceps muscle during the patellar grind test. The present investigation aims to elucidate the association between patellofemoral grind and synovitis in the knee osteoarthritis (KOA).

Method

A total of 1,119 knees with complete patellofemoral grind and synovitis assessment records from the Osteoarthritis Initiative (OAI) were investigated in this study. The Magnetic Resonance Imaging at baseline, 12 months, and 24 months of follow-up were employed to evaluate synovitis. Frequent patellofemoral grind was operationally defined as occurring more than twice at three different time points. In addition, a sensitivity stratification was conducted to examine gender differences.

Results

The study participants had an average age of 61 years, with 62.4% being female. The findings revealed that baseline patellofemoral grind was significantly associated with changes in synovitis at follow-up (odds ratio [OR]: 1.44, confidence interval [CI]: 1.04-1.98) and was also linked to synovitis worsening over 24 months (OR: 1.67, CI: 1.13-2.46) in all subjects. For the subjects with frequent patellofemoral grind, this correlation was more significant (OR: 1.50, CI: 1.03-2.16; OR: 1.71, CI: 1.09-2.67). In the context of sensitivity stratification, it was observed that the baseline and frequent patellofemoral grind in females exhibited a significant correlation with synovitis. However, no significant correlation was found in males.

Conclusion

Patellofemoral grind may serve as a potential risk factor of synovitis in knee osteoarthritis, particularly among female patients, and thus, necessitates close monitoring and management by clinical physicians.

Comparing kinematic asymmetry and lateral step-down test scores in healthy, chronic ankle instability, and patellofemoral pain syndrome female basketball players: a cross-sectional study

We aimed to understand whether ankle dorsiflexion range of motion (ROM) and dynamic knee valgus (DKV) kinematic inter-limb asymmetries would be associated with the Lateral Step-Down Test (LSD) in basketball players with chronic ankle instability (CAI), patellofemoral pain (PFP) and healthy controls (HC). An observational cross-sectional study with a between-subject design was employed. Female basketball athletes with CAI (n = 20), PFP (n = 20) and HC (n = 20) were recruited. Ankle dorsiflexion-ROM, DKV angle during a single-limb squat, and LSD quality were measured bilaterally. The Asymmetry index (ASI) was calculated to identify between-limb percentage imbalances. The correlation matrix between the tasks was calculated. Ankle dorsiflexion-ROM was less in the CAI and PFP than in the HC group regardless of limb (p < 0.001). DKV angle was greater in the CAI and PFP than in the HC group bilaterally (p < 0.001). LSDs were similar between the PFP and CAI groups (p = 0.698) but worse than the HC group (p = 0.001). The ASI showed asymmetry across all tasks (p < 0.001), with the greatest asymmetry for the DKV angle. The correlation matrix between tasks on both limbs was significant (p < 0.05). Our findings suggest significant asymmetries in ankle dorsiflexion-ROM and frontal plane knee control are present in female basketball athletes with CAI and PFP, and thus, highlights need to evaluate and reduce limb asymmetries in these populations.

A fused biometrics information graph convolutional neural network for effective classification of patellofemoral pain syndrome

Patellofemoral pain syndrome (PFPS) is a common, yet misunderstood, knee pathology. Early accurate diagnosis can help avoid the deterioration of the disease. However, the existing intelligent auxiliary diagnosis methods of PFPS mainly focused on the biosignal of individuals but neglected the common biometrics of patients. In this paper, we propose a PFPS classification method based on the fused biometrics information Graph Convolution Neural Networks (FBI-GCN) which focuses on both the biosignal information of individuals and the common characteristics of patients. The method first constructs a graph which uses each subject as a node and fuses the biometrics information (demographics and gait biosignal) of different subjects as edges. Then, the graph and node information [biosignal information, including the joint kinematics and surface electromyography (sEMG)] are used as the inputs to the GCN for diagnosis and classification of PFPS. The method is tested on a public dataset which contain walking and running data from 26 PFPS patients and 15 pain-free controls. The results suggest that our method can classify PFPS and pain-free with higher accuracy (mean accuracy = 0.8531 ± 0.047) than other methods with the biosignal information of individuals as input (mean accuracy = 0.813 ± 0.048). After optimal selection of input variables, the highest classification accuracy (mean accuracy = 0.9245 ± 0.034) can be obtained, and a high accuracy can still be obtained with a 40% reduction in test variables (mean accuracy = 0.8802 ± 0.035). Accordingly, the method effectively reflects the association between subjects, provides a simple and effective aid for physicians to diagnose PFPS, and gives new ideas for studying and validating risk factors related to PFPS.

Brain Activity During Experimental Knee Pain and Its Relationship With Kinesiophobia in Patients With Patellofemoral Pain: A Preliminary Functional Magnetic Resonance Imaging Investigation

Context: The etiology of patellofemoral pain has remained elusive, potentially due to an incomplete understanding of how pain, motor control, and kinesiophobia disrupt central nervous system functioning. Objective: To directly evaluate brain activity during experimental knee pain and its relationship to kinesiophobia in patients with patellofemoral pain. Design: Cross-sectional. Methods: Young females clinically diagnosed with patellofemoral pain (n = 14; 14.4 [3.3] y; body mass index = 22.4 [3.8]; height = 1.61 [0.1] m; body mass = 58.4 [12.7] kg). A modified Clarke test (experimental pain condition with noxious induction via patella pressure and quadriceps contraction) was administered to the nondominant knee (to minimize limb dominance confounds) of patients during brain functional magnetic resonance imaging (fMRI) acquisition. Patients also completed a quadriceps contraction without application of external pressure (control contraction). Kinesiophobia was measured using the Tampa Scale of Kinesiophobia. The fMRI analyses assessed brain activation during the modified Clarke test and control contraction and assessed relationships between task-induced brain activity and kinesiophobia. Standard processing for neuroimaging and appropriate cluster-wise statistical thresholds to determine significance were applied to the fMRI data (z > 3.1, P < .05). Results: The fMRI revealed widespread neural activation in the frontal, parietal, and occipital lobes, and cerebellum during the modified Clarke test (all zs > 4.4, all Ps < .04), whereas neural activation was localized primarily to frontal and cerebellar regions during the control contraction test (all zs > 4.4, all Ps < .01). Greater kinesiophobia was positively associated with greater activity in the cerebello-frontal network for the modified Clarke test (all zs > 5.0, all Ps < .01), but no relationships between kinesiophobia and brain activity were observed for the control contraction test (all zs < 3.1, all Ps > .05). Conclusions: Our novel experimental knee pain condition was associated with alterations in central nociceptive processing. These findings may provide novel complementary pathways for targeted restoration of patient function.

Correlation between Chondromalacia Patella and Patellofemoral Factors in Middle-Age Population: A Clinical, Functional, and Radiological Analysis

Background Despite higher incidence of patellofemoral pain (PFP) and consequently morbidity, the understanding about PF factors leading to PF arthritis is way lacking.

Material and Methods A prospective study of first 80 patients who were diagnosed with chondromalacia patella (CMP) on magnetic resonance imaging (MRI) divided into early and late CMP groups were evaluated clinically, radiologically, and in terms of functional outcome.

Results : Quadriceps angle, Clark’s test, and Insall–Salvati ratio results were nonsignificant despite greater values were observed in late CMP group, whereas trochlear morphology results (sulcus angle: 153:138 degrees and sulcus depth 3.9:5.4 mm) and clinical scores were significant in late CMP group (Kujala’s score: 61:78, whereas PF pain score: 43:25). Type-C patellar morphology was found in greater number in late CMP cohort.

Conclusion Trochlear and patellar morphologies along with clinical scores play a key role in understanding of the CMP.

Patient-reported outcome after patient-specific unicondylar knee arthroplasty for unicompartmental knee osteoarthritis

BACKGROUND

Unicondylar knee arthroplasty was introduced in the late 1960s and remains a topic of controversial discussion. Patient-specific instruments and patient-specific implants are not yet the standard of care. The question remains whether this time-consuming and costly technique can be beneficial for the patient. The aim of this study was to evaluate whether a custom-made unicondylar knee arthroplasty leads to improved patient-reported outcome.

METHODS

This retrospective study evaluates the patient-reported outcome after custom-made unicondylar knee arthroplasty (CM-UKA, ConforMIS™ iUni® G2, ConforMIS Inc., Billerica, MA, USA). We evaluated 29 patients (31 knees) at an average of 2.4 years (range 1.2-3.6 years) after operation for unicondylar osteoarthritis of the knee. The target zone for the postoperative leg axis was a slight under-correction of 0-2° varus. Follow-up evaluation included the Forgotten Joint Score (FJS), the Knee Society Score (KSS), a Visual Analogue Scale (VAS) and a radiographic evaluation including a long-leg radiograph. Primary outcome measure was patient satisfaction based on the Forgotten Joint Score.

RESULTS

We found an excellent postoperative health-related quality of life with a mean FJS of 76.8 (SD 17.9) indicating a low level of joint awareness after CM-UKA. The mean preoperative KSS was 66.0 (SD 13.71) and 59.4 (17.9) for the KSS function score. The increase was 22.8 points for the KSS knee score (p < 0.0001) and 34.8 points for the KSS function score (p < 0.0001). The VAS for pain decreased from a mean of 5.4 (SD 1.8) to 1.1 (SD 1.2) (p < 0.0001). The malalignment rate with a postoperative deviation of more than 2° in the leg axis was 29%. There was no evidence of component loosening after a mean follow-up of 2.4 years.

CONCLUSIONS

Custom-made unicondylar knee arthroplasty (CM-UKA) can provide improved clinical and functional outcomes for patients with isolated knee osteoarthritis of the medial compartment. We found excellent results regarding patient satisfaction and a low malalignment rate for CM-UKA. Further studies are needed to investigate long-term survivorship of the implant.

LEVEL OF EVIDENCE

Level IV.

TRIAL REGISTRATION

Trial Registration number: Z-2014-0389-10 Regensburg Clinical Studies Center (REGCSC) 09/07/2014.

Assessment and Management of Somatic Dysfunctions in Patients With Patellofemoral Pain Syndrome

Context

Patellofemoral pain syndrome (PFPS) is one of the most common determinants of knee pain. The causes of PFPS are multifactorial, and most treatment approaches are conservative. There are many kinds of therapy for this syndrome, which are based on building strength, flexibility, proprioception, and endurance. Training is functional and progression is gradual. Our hypothesis is that total-body osteopathic manipulative therapy (OMTh; manipulative care provided by foreign-trained osteopaths) focused on the management of somatic dysfunctions could be useful for managing the pain of patients with PFPS.

Objective

To investigate the effect of OMTh on pain reduction in patients with PFPS.

Methods

This pilot study was randomized, controlled, and single-blinded with 2 months of follow-up. Qualified participants were randomly assigned to 1 of 2 groups: OMTh group or placebo group. Each participant received either 4 sessions of OMTh or 4 sessions of manual placebo intervention that consisted of passive touching without joint mobilization in a protocolled order. A visual analogue scale (VAS) was used to assess general knee pain, peripatellar pain, pain after prolonged sitting, pain during the patellar compression test, and pain during stair ascent and descent. Pain assessment was performed before the baseline (T0), second (T1), third (T2), and fourth (T3) sessions, and follow-up (T4) was performed 8 weeks after T3.

Results

Thirty-five participants were enrolled the study. The VAS score was significantly reduced and clinically relevant in the OMTh group after each treatment and after 2 months of follow-up. The change in the VAS score before each treatment indicates that the most improved areas at T1 compared with T0 were lumbar and sacral with improvements in 83% and 40% of patients, respectively. At T2 compared with T1, the most improved areas were cervical and sacral with improvements found in 58% and 36% of patients, respectively. The number of dysfunctions that were diagnosed decreased during the baseline to T3 period (40% change). The correlation analysis showed significant results for the dysfunction and the compression test at T2 (P=.01, ρ=0.543).

Conclusion

Significant differences in VAS scores were found between the OMTh and placebo groups. These findings underline how OMTh can lead to reduced pain in patients with PFPS.

Unilateral anterior knee pain is associated with increased patellar lateral position after stressed lateral translation

PURPOSE

To objectively compare side-to-side patellar position and mobility in patients with idiopathic unilateral anterior knee pain (AKP) using a stress-testing device concomitantly with magnetic resonance imaging. It is hypothesized that the painful knees present greater patellar mobility than the contralateral non-painful knees.

METHODS

From a total sample of 359 patients, 23 patients with idiopathic unilateral AKP (30.9 years, 23.4 kg/m², 43% males) were included within the present study. Both knees of all the patients were examined by conventional imaging, including the measurement of trochlear sulcus angle, Caton-Deschamps index, tibial tuberosity to trochlear groove distance, patellar tilt angle and patellar subluxation (both at rest and upon quadriceps contraction). Additionally, the same patients underwent stress testing (Porto Patella Testing Device); these measurements were taken with the patella at rest, after lateral patellar translation and after lateral patellar tilt. Clinical and functional outcomes were obtained using physical examination and the Kujala and Lysholm scores.

RESULTS

Painful knees showed statistically significant higher patellar lateral position after stressed lateral translation than non-painful knees (p = 0.028), 9.8 ± 3.6 mm and 7.1 ± 6.3 mm, respectively. The adjusted multivariate logistic model identified the patellar position after lateral displacement to be significantly associated with AKP (OR = 1.165) and the model (AUC = 0.807, p < 0.001) showed reasonable sensitivity (67%) and specificity (73%).

CONCLUSION

Patients with idiopathic unilateral AKP with morphologically equivalent knees showed statistically significant increased patellar lateral position after stressed lateral displacement in their painful knee. The greater lateral patellar mobility quantified by the PPTD testing brings more objectivity to the diagnosis.

LEVEL OF EVIDENCE

II.

Use of Exogenous Hyaluronic Acid for the Treatment of Patellar Chondropathy- A Six-Month Randomized Controlled Trial

Objective  To evaluate the clinical and radiological benefits of intra-articular exogenous hyaluronic acid for the treatment of chondral patellar injury. Method  Randomized clinical trial with 70 patients divided into 2 groups: those submitted to physical therapy for 3 months, and those submitted to physical therapy associated with the intra-articular administration of 2 mL of hyaluronic acid for the same period, who had anterior knee pain and patellar cartilage injury of grades II or III with no significant bone abnormalities. The functional scores and the characteristics of the physical and imaging exams were evaluated before and 3 and 6 months after the treatment. Result  The average age of the patients was 32 ± 7.6 years. Patients from the hyaluronic acid group had better Kujala et al and Lysholm scores, and lower pain scores after 3 and 6 months of treatment when compared to the control group. The incidence of positive Clarke maneuver was lower in the treated group, but there was no difference in the magnetic resonance imaging classification. Conclusion  Patients with patellar chondropathy of grades II or III treated with hyaluronic acid and physical therapy had less pain (visual analogue scale, VAS), and better functional results in the Lysholm and Kujala et al questionnaires after 3 and 6 months of treatment compared to patients undergoing physical therapy alone. In addition, the number of cases with a negative Clarke maneuver was larger in the treated group after 6 months of treatment.

The Effect of Valgus Control Instruction Exercises on Pain, Strength, and Functionality in Active Females With Patellofemoral Pain Syndrome

BACKGROUND

Patellofemoral pain syndrome (PFPS) is sometimes related to excessive hip adduction and internal rotation, as well as knee valgus during weightbearing activities in females. Research on injury prevention and rehabilitation strategies has shown the positive effects of valgus control instruction (VCI) exercise programs in training.

HYPOTHESIS

A VCI program would result in a positive change in pain, eccentric hip muscle torque, and performance in females with PFPS.

STUDY DESIGN

Controlled laboratory study.

LEVEL OF EVIDENCE

Level 1.

METHODS

Sixty-four amateur female volleyball players from our university (age, 18-25 years) with PFPS and equal years of exercise experience were randomly divided into VCI (n = 32; age, 22.1 ± 5.88 years) and control (n = 32; age, 23.1 ± 6.49 years) groups. Function (single, triple, and crossover hops), strength (hip abductor and external rotators), pain (visual analog scale), and knee valgus angle (single-leg squat) were assessed at baseline and after intervention.

RESULTS

There was a significant difference before and after implementation of the VCI program with regard to pain (49.18% ↓, P = 0.000), single-leg hop test (24.62% ↑, P = 0.000), triple-hop test (23.75% ↑, P = 0.000), crossover hop test (12.88% ↑, P = 0.000), single-leg 6-m timed hop test (7.43% ↓, P = 0.000), knee dynamic valgus angle (59.48% ↓, P = 0.000), peak abductor to adductor eccentric torque ratio (14.60% ↑, P = 0.000), peak external (59.73% ↑, P = 0.023) and internal rotator (15.45% ↑, P = 0.028) eccentric torques, and the ratio of peak external to internal rotator eccentric torque (40.90% ↑, P = 0.000) ( P < 0.05).

CONCLUSION

PFPS rehabilitation and prevention programs should consider VCI exercises to decrease pain, improve strength, and increase athletes' functional performance.

CLINICAL RELEVANCE

This study investigated the effect of VCI exercises on knee valgus angle, pain, and functionality of individuals with PFPS. The VCI program improves performance, knee dynamic valgus angle, and strength in participants with PFPS. A controlled and optimal knee valgus angle during a functional task is the most important factor for injury prevention specialists. VCI training can be used as a supplemental method to prevent and treat lower extremity injury in patients with PFPS.

Associations of Joint Line Tenderness and Patellofemoral Grind With Long-Term Knee Joint Outcomes: Data From the Osteoarthritis Initiative

OBJECTIVE

To examine whether joint line tenderness and patellofemoral grind from physical examination were associated with cartilage volume loss, worsening of radiographic osteoarthritis, and the risk of total knee replacement.

METHODS

This study examined 4,353 Osteoarthritis Initiative participants. For each measurement of joint line tenderness and patellofemoral grind, the patterns were defined as no (none at baseline and at 1 year), fluctuating (present at either time point), and persistent (present at both time points). Cartilage volume loss and worsening of radiographic osteoarthritis over 4 years were assessed using magnetic resonance imaging and radiographs, and total knee replacement over 6 years was assessed.

RESULTS

A total of 35.0% of participants had joint line tenderness, and 15.8% had patellofemoral grind. Baseline patellofemoral grind, but not joint line tenderness, was associated with increased cartilage volume loss (1.08% per year versus 0.96% per year; P = 0.02) and an increased risk of total knee replacement (odds ratio [OR] 1.55 [95% confidence interval (95% CI) 1.11-2.17]; P = 0.01). While the patterns of joint line tenderness were not significantly associated with joint outcomes, participants with persistent patellofemoral grind had an increased rate of cartilage volume loss (1.30% per year versus 0.90% per year; P < 0.001) and an increased risk of total knee replacement (OR 2.10 [95% CI 1.30-3.38]; P = 0.002) compared with those participants without patellofemoral grind.

CONCLUSION

Patellofemoral grind, but not joint line tenderness, may represent a clinical marker associated with accelerated cartilage volume loss over 4 years and an increased risk of total knee replacement over 6 years. This simple clinical examination may provide clinicians with an inexpensive way to identify those at higher risk of disease progression who should be targeted for surveillance and management.

A novel clinical test for assessing patellar cartilage changes and its correlation with magnetic resonance imaging and arthroscopy

Controversy still exists regarding the best clinical assessment test for chondromalacia patellae (CMP). Our study aims to evaluate the specificity and sensitivity of a novel clinical test for CMP, the "Patella Slide Test" (PST) against the findings of magnetic resonance imaging (MRI) and arthroscopy. We included 221 consecutive patients planned for elective knee arthroscopic surgery. An MRI scan of the symptomatic knee was performed prior to surgery. On the day of surgery, each patient was examined using the PST followed by a knee arthroscopy to assess the quality of the chondral surfaces of the patellofemoral joint. The MRI and PST results were compared against the arthroscopic findings that served as the gold standard. The PST (0.89) was statistically more sensitive than MRI (0.67) in diagnosing CMP. The PST (0.89) also had a greater negative predictive value (NPV) than MRI (0.74). However, MRI (0.94) was more specific than the PST (0.85). The differences in accuracy and positive predictive value of the PST versus MRI were not statically significant. In conclusion, the PST shows high sensitivity and has a greater NPV than MRI as a clinical test for diagnosing CMP.

Patellofemoral pain in athletes: clinical perspectives

Patellofemoral pain (PFP) is a very common problem in athletes who participate in jumping, cutting and pivoting sports. Several risk factors may play a part in the pathogenesis of PFP. Overuse, trauma and intrinsic risk factors are particularly important among athletes. Physical examination has a key role in PFP diagnosis. Furthermore, common risk factors should be investigated, such as hip muscle dysfunction, poor core muscle endurance, muscular tightness, excessive foot pronation and patellar malalignment. Imaging is seldom needed in special cases. Many possible interventions are recommended for PFP management. Due to the multifactorial nature of PFP, the clinical approach should be individualized, and the contribution of different factors should be considered and managed accordingly. In most cases, activity modification and rehabilitation should be tried before any surgical interventions.

Characteristics and Outcome of Patellofemoral Pain in Adolescents: Do They Differ From Adults?

Study Design Case series with 1-year follow-up. Background Most of the recommendations for the diagnosis, treatment, and prognosis of patellofemoral pain (PFP) are based on research performed in adults. The literature suggests that there are potential differences between adolescents and adults with PFP. Objectives To investigate differences in characteristics, symptoms, and prognosis at 1-year follow-up between adolescents and adults with PFP. Methods Data from 64 patients with PFP, assessed at baseline and 1-year follow-up, were used. At baseline, data on demographics, symptoms, and coping strategies were obtained by questionnaire. Physical examination included strength and flexibility measurements of the quadriceps and hamstrings. At 1-year follow-up, a questionnaire was used to collect data on pain, function, and recovery. Differences between adolescents (14-18 years) and adults (18-40 years) were analyzed using regression techniques, adjusted for sex, body mass index, and the presence of bilateral pain. Results Of the 64 patients with PFP included at baseline, 78.1% were available for follow-up. At baseline, adolescents with PFP had a significantly lower body mass index (20.7 versus 24.9 kg/m²) and a greater percentage of bilateral pain (70% versus 43.2%) than adults with PFP. There were no differences in reported pain and symptoms between the 2 groups. In total, 25% of the adolescents regarded themselves as recovered after 1 year, compared to 22.7% of the adults (adjusted P = .725). Conclusion The sample size of the study, in relation to the number of statistical tests performed, urges caution in the interpretation of the results. In contrast to what has been suggested previously, only minor differences seem to exist between adolescents and adults with PFP. In both groups, PFP is clearly not a self-limiting disease, with nearly 75% of those in this study reporting persistent pain at 1-year follow-up. Level of Evidence Prognosis, level 4. J Orthop Sports Phys Ther 2017;47(10):801-805. Epub 4 Sep 2017. doi:10.2519/jospt.2017.7326.

Physical Examination of the Knee: Meniscus, Cartilage, and Patellofemoral Conditions

The knee is one of the most commonly injured joints in the body. Its superficial anatomy enables diagnosis of the injury through a thorough history and physical examination. Examination techniques for the knee described decades ago are still useful, as are more recently developed tests. Proper use of these techniques requires understanding of the anatomy and biomechanical principles of the knee as well as the pathophysiology of the injuries, including tears to the menisci and extensor mechanism, patellofemoral conditions, and osteochondritis dissecans. Nevertheless, the clinical validity and accuracy of the diagnostic tests vary. Advanced imaging studies may be useful adjuncts.

EXAMINATION OF THE PATELLOFEMORAL JOINT

Patellofemoral pain is one of the leading causes of knee pain in athletes. The many causes of patellofemoral pain make diagnosis unpredictable and examination and treatment difficult. This clinical commentary discusses a detailed physical examination routine for the patient with patellofemoral pain. Critically listening and obtaining a detailed medical history followed by a clearly structured physical examination will allow the physical therapist to diagnose most forms of patellofemoral pain. This clinical commentary goes one step further by suggesting an examination scheme and order in which it should be performed during the examination process. This step-by-step guide will be helpful for the student or novice therapist and serve as review for those that are already well versed in patellofemoral examination.

Structural Abnormalities on Magnetic Resonance Imaging in Patients With Patellofemoral Pain: A Cross-sectional Case-Control Study

BACKGROUND

Structural abnormalities of the patellofemoral joint might play a role in the pathogenesis of patellofemoral pain (PFP), a common knee problem among young and physically active individuals. No previous study has investigated if PFP is associated with structural abnormalities of the patellofemoral joint using high-resolution magnetic resonance imaging (MRI).

PURPOSE

To investigate the presence of structural abnormalities of the patellofemoral joint on high-resolution MRI in patients with PFP compared with healthy control subjects.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients with PFP and healthy control subjects between 14 and 40 years of age underwent high-resolution 3-T MRI. All images were scored using the Magnetic Resonance Imaging Osteoarthritis Knee Score with the addition of specific patellofemoral features. Associations between PFP and the presence of structural abnormalities were analyzed using logistic regression analyses adjusted for age, body mass index (BMI), sex, and sports participation.

RESULTS

A total of 64 patients and 70 control subjects were included in the study. Mean ± SD age was 23.2 ± 6.4 years, mean BMI ± SD was 22.9 ± 3.4 kg/m(2), and 56.7% were female. Full-thickness cartilage loss was not present. Minor patellar cartilage defects, patellar bone marrow lesions, and high signal intensity of the Hoffa fat pad were frequently seen in both patients (23%, 53%, and 58%, respectively) and control subjects (21%, 51%, and 51%, respectively). After adjustment for age, BMI, sex, and sports participation, none of the structural abnormalities were statistically significantly associated with PFP.

CONCLUSION

Structural abnormalities of the patellofemoral joint have been hypothesized as a factor in the pathogenesis of PFP, but the study findings suggest that structural abnormalities of the patellofemoral joint on MRI are not associated with PFP.

No Difference on Quantitative Magnetic Resonance Imaging in Patellofemoral Cartilage Composition Between Patients With Patellofemoral Pain and Healthy Controls

BACKGROUND

Retropatellar cartilage damage has been suggested as an etiological factor for patellofemoral pain (PFP), a common knee condition among young and physically active individuals. To date, there is no conclusive evidence for an association between cartilage defects and PFP. Nowadays, advanced quantitative magnetic resonance imaging (MRI) techniques enable estimation of cartilage composition.

PURPOSE

To investigate differences in patellofemoral cartilage composition between patients with PFP and healthy control subjects using quantitative MRI.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

Patients with PFP and healthy control subjects underwent 3.0-T MRI including delayed gadolinium-enhanced MRI of cartilage and T1ρ and T2 mapping. Differences in relaxation times of patellofemoral cartilage were compared between groups by linear regression analyses, adjusted for age, body mass index, sex, sports participation, and time of image acquisition.

RESULTS

This case-control study included 64 patients and 70 controls. The mean (±SD) age was 23.2 ± 6.4 years and the mean body mass index was 22.9 ± 3.4 kg/m(2); 56.7% were female. For delayed gadolinium-enhanced MRI of cartilage, the mean T1GD relaxation times of patellar (657.8 vs 669.4 ms) and femoral cartilage (661.6 vs 659.8 ms) did not significantly differ between patients and controls. In addition, no significant difference was found in mean T1ρ relaxation times of patellar (46.9 vs 46.0 ms) and femoral cartilage (50.8 vs 50.2 ms) and mean T2 relaxation times of patellar (33.2 vs 32.9 ms) and femoral cartilage (36.7 vs 36.6 ms) between patients and controls. Analysis of prespecified medial and lateral subregions within the patellofemoral cartilage also revealed no significant differences.

CONCLUSION

There was no difference in composition of the patellofemoral cartilage, estimated with multiple quantitative MRI techniques, between patients with PFP and healthy control subjects. However, clinically relevant differences could not be ruled out for T1ρ in the adolescent population. Retropatellar cartilage damage has long been hypothesized as an important factor in the pathogenesis of PFP, but study findings suggest that diminished patellofemoral cartilage composition is not associated with PFP.

Joint Motion Quality in Chondromalacia Progression Assessed by Vibroacoustic Signal Analysis

BACKGROUND

Because of the specific biomechanical environment of the patellofemoral joint, chondral disorders, including chondromalacia, often are observed in this articulation. Chondromalacia via pathologic changes in cartilage may lead to qualitative impairment of knee joint motion.

OBJECTIVE

To determine the patellofemoral joint motion quality in particular chondromalacia stages and to compare with controls.

DESIGN

Retrospective, comparative study.

SETTING

Voivodship hospitals, university biomechanical laboratory.

PATIENTS

A total of 89 knees with chondromalacia (25 with stage I; 30 with stage II and 34 with stage III) from 50 patients and 64 control healthy knees (from 32 individuals).

METHODS

Vibroacoustic signal pattern analysis of joint motion quality.

MAIN OUTCOME MEASUREMENTS

For all knees vibroacoustic signals were recorded. Each obtained signal was described by variation of mean square, mean range (R4), and power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) parameters.

RESULTS

Differences between healthy controls and all chondromalacic knees as well as chondromalacia patellae groups were observed as an increase of analyzed parameters (P < .001) with only one exception. No statistically significant difference between control group and stage I of chondromalacia patellae was found. All chondromalacia groups were differentiated by the use of all analyzed parameters (P < .01), whose values correspond to the progress of chondromalacia.

CONCLUSIONS

Chondromalacia generates abnormal vibroacoustic signals, and there seems to be a relationship between the level of signal amplitude as well as frequency and cartilage destruction from the superficial layer to the subchondral bone.

LEVEL OF EVIDENCE

IV.

Minimally invasive medial patellofemoral ligament reconstruction for patellar instability using an artificial ligament: A two year follow-up

BACKGROUND

Recurrence of acute patellar dislocation affects approximately 30% of individuals, and up to 75% of those with grade IV instability. The medial patellofemoral ligament (MPFL) is considered to be critical for patellar stabilization. MPFL reconstruction with allografts has been proposed to reduce risk of recurrence, but there is limited evidence about the safety and effectiveness of techniques using synthetic allografts.

METHODS

We present a retrospective case series of 29 individuals who underwent a MPFL reconstruction between 2009 and 2012, using an artificial ligament for patellar instability by a single surgeon. Clinical, radiological and functional outcomes were measured at a minimum of 24 months.

RESULTS

31 knees (29 individuals) were followed up for a median of 43 (range: 24-68) months. Using the Crosby and Insall grading system, 21 (68%) were graded as excellent, nine (29%) were good, one (3%) as fair and none as worse at 24 months. The mean improvement in Lysholm knee score for knee instability was 68 points (standard deviation 10). Ligamentous laxity was seen in 17 (55%) of individuals. In this subset, 12 were graded as excellent, four as good and one as fair. The mean improvement in patellar height was 11% at three months follow-up. All knees had a stable graft fixation with one re-dislocation following trauma.

CONCLUSIONS

We propose a minimally invasive technique to reconstruct the MPFL using an artificial ligament allowing early mobilization without bracing. This study indicates the procedure is safe, with a low risk of re-dislocation in all grades of instability.

LEVEL OF EVIDENCE

Level IV Case Series.

Intra- and Inter-session Reliability of Static and Dynamic Postural Control in Participants with and without Patellofemoral Pain Syndrome

PURPOSE

To determine the intra- and inter-session reliability of balance performance in people with patellofemoral pain syndrome (PFPS) and matched controls.

METHODS

In this methodological study, single-leg-stance performance of 15 participants with unilateral PFPS and 15 healthy matched controls was assessed using the Biodex Balance System (BBS) under 4 task difficulty levels (static and dynamic, with and without visual feedback). Intra-class correlation coefficients (ICCs), standard errors of measurement, and coefficients of variation were calculated for the overall stability index, anterior-posterior stability index, and medial-lateral stability index.

RESULTS

Static and dynamic postural performance during single-leg stance showed moderate to very high reliability in the PFPS group (ICCs=0.53-0.96) and in healthy control participants (ICCs=0.51-0.91). Both measures were more reliable with eyes closed than with eyes open.

CONCLUSION

BBS stability indices appear to have acceptable reliability in people with PFPS, particularly in more challenging conditions, and may be incorporated into the evaluation and rehabilitation of this patient group.

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.

Clinically insignificant association between anterior knee pain and patellofemoral lesions which are found incidentally

BACKGROUND

Patellofemoral chondral lesions are frequently identified incidentally during the arthroscopic treatment of other knee pathologies. A role has been described for arthroscopic debridement when symptoms are known to originate from pathology of the patellofemoral joint. However, it remains unclear how to manage lesions which are found incidentally whilst tackling other pathologies. The purpose of this study was to establish the strength of association between anterior knee pain and patellofemoral lesions identified incidentally in a typical arthroscopic population.

METHODS

A consecutive series of patients undergoing arthroscopy for a range of standard indications formed the basis of this cross section study. We excluded those with patellofemoral conditions in order to identify patellofemoral lesions which were solely incidental. Pre-operative assessments were performed on 64 patients, where anterior knee pain was sought by three methods: an annotated photographic knee pain map (PKPM), patient indication with one finger and by palpated tenderness. A single blinded surgeon, performed standard arthroscopies and recorded patellofemoral lesions. Statistical correlations were performed to identify the association magnitude.

RESULTS

Associations were identified between incidental patellofemoral lesions and tenderness palpated on the medial patella (P = 0.007, χ(2) = 0.32) and the quadriceps tendon (P = 0.029, χ(2) = 0.26), but these associations were at best fair, which could be interpreted as clinically insignificant.

CONCLUSION

Incidental patellofemoral lesions are not necessarily associated with anterior knee pain, we suggest that they could be left alone. This recommendation is only applicable to patellofemoral lesions which are found incidentally whilst addressing other pathology.