Patellofemoral pain syndrome in the female athlete

The effects of ankle dorsiflexor fatigue on lower limb biomechanics during badminton forward forehand and backhand lunge

Background: Local muscle fatigue may have an adverse effect on the biomechanics of the lunge movement and athletic performance. This study analyzed the biomechanical indicators of the forward lunge in badminton players before and after fatigue of the ankle dorsiflexors. Methods: Using the isometric muscular strength testing system, 15 badminton players underwent an ankle dorsiflexor fatigue test. Before and after the fatigue experiment, five lunges were done in both the forehand forward (FH) and backhand forward (BH) directions, five in each direction. A Vicon motion capture system and an AMTI force measuring station were used to record lower limb kinematic and ground reaction force (GRF). Pre-fatigue and post-fatigue variability were determined using paired-samples t-tests, Wilcoxon signed rank test, and Statistical Non-parametric Mapping (SNPM). Result: The results showed that after fatigue, the peak angle of ankle dorsiflexion was significantly reduced (p = 0.034), the range of motion (ROM) of the ankle sagittal plane (p = 0.000) and peak angle of ankle plantarflexion (p = 0.001) was significantly increased after forehand landing. After fatigue, ankle inversion was significantly increased after forehand and backhand landings (FH: p = 0.033; BH: p = 0.015). After fatigue, peak knee flexion angles increased significantly (FH: Max: p = 0.000, Min: p = 0.000; BH: Max: p = 0.017, Min: p = 0.037) during forehand and backhand landings and ROM in knee flexion and extension increased (p = 0.009) during forehand landings. Knee inversion range of motion was significantly increased after fatigue (p = 0.024) during forehand landings. Peak hip flexion angle (p = 0.000) and range of motion (p = 0.000) were significantly reduced in forehand landings after fatigue. The mean loading rate (p = 0.005) and the maximum loading rate (p = 0.001) increased significantly during backhand landings after fatigue. Post-fatigue, the center of pressure (COP) frontal offset increased significantly (FH: p = 0.000; BH: p = 0.000) in the forehand and backhand landings. Conclusion: These results indicate that when the ankle dorsiflexors are fatigued, the performance of the forehand is significantly negatively affected, and the impact force of the backhand is greater.

Overview of Sport-Specific Injuries

Athletes are at risk for a variety of injuries not typically sustained in everyday life. The team physician must be capable of not only identifying and treating injuries as they occur, but he or she must be armed with the knowledge to minimize the risk of injuries before they occur. This review serves to provide an overview of the various sport-specific injuries typically encountered by team physicians. Injuries are grouped by body part and/or organ system, when possible. We do not aim to cover in detail the various treatments for these injuries; rather, we hope that this article provides a comprehensive overview of sport-specific injury, and demonstrate the well-roundedness in skills that must be possessed by team physicians.

French translation and validation of the "Anterior Knee Pain Scale" (AKPS)

PURPOSE

To linguistically and cross-culturally translate the Anterior Knee Pain Scale into French and to evaluate the reliability and validity of this translated version of the questionnaire.

METHODS

The translation part was performed in six stages, according to international guidelines: (i) two initial translations from English to French; (ii) synthesis of the two translations; (iii) backward translations into the original language; (iv) expert committee to compare the backward translations with the original questionnaire; (v) pre-final version testing and (VI) expert committee appraisal. To validate the French version of the Anterior Knee Pain Scale, we assessed its validity, reliability and floor/ceiling effects. To do this, volunteer patients from the French part of Belgium and from France, with patellofemoral pain were asked to answer the French version of the Anterior Knee Pain Scale at baseline and after 7 days, as well as the generic SF-36 questionnaire.

RESULTS

The Anterior Knee Pain Scale was translated without any major difficulties. A total of 101 subjects aged 34.5 ± 11.4 years (58.4% of women) were included in this study. Results indicated an excellent test-retest reliability (Intra-class correlation coefficient (ICC) = 0.97, 95%CI: 0.96-0.98), a high internal consistency (Cronbach's alpha = 0.87), a consistent construct validity (high correlations with the SF-36 questionnaire were found with domains related to physical function (r = 0.80), physical role (r = 0.70) and pain (r = 0.64)) and low or moderate correlations with domains related to mental health (r = 0.26), vitality (r = 0.32) and social function (r = 0.41). Moreover, no floor/ceiling effects have been found.

CONCLUSIONS

A valid French version of the Anterior Knee Pain Scale is now available and can be used with confidence to better assess the disease burden associated with patellofemoral pain. It was successfully cross-culturally adapted into French. Implications for rehabilitation The results on psychometric properties of the French Anterior Knee Pain Scale are comparable with six validated versions obtained for the Finnish, the Turkish, the Chinese, the Dutch, the Thai and the Persian populations. The French translated version of the Anterior Knee Pain Scale is a reliable and valid instrument for assessing the functional limitations associated with patellofemoral pain. The test-retest reliability of the French Anterior Knee Pain Scale was excellent, the internal consistency was high and the construct validity was consistent. There were no floor/ceiling effects.

Comparing goniometric and radiographic measurement of Q angle of the knee

Background

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

Objectives

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

Methods

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

Results

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

Conclusions

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

Unusual Presentation of Anterior Knee Pain in Elite Female Athletes: Report of Two Cases

Two elite female athletes presented with anterior knee pain with range of motion and reproducible tenderness to palpation. Diagnostic arthroscopy was performed in both cases resulting in excision of a nodular pigmented villonodular synovitis (PVNS) in the first patient and scar tissue in the second patient. Correct diagnosis of anterior knee pain in the elite female athlete can present a challenge to clinicians. Although patellofe-moral pain is the most common diagnosis, other uncommon causes include PVNS and residual scar formation in patients with a history of surgery or trauma. Magnetic resonance imaging (MRI) images are helpful in confirming the diagnosis, however, in a subset of patients, the physician must rely on clinical suspicion and physical exam to make the proper diagnosis. Given the possibility of a false negative MRI images, patients with persistent anterior knee pain with a history of knee surgeries and focal tenderness reproducible on physical exam may benefit from a diagnostic arthroscopy.

Is there a role of pulsed electromagnetic fields in management of patellofemoral pain syndrome? Randomized controlled study at one year follow-up

Patellofemoral pain syndrome (PFPS) is a common cause of recurrent or chronic knee pain in young adults, generally located in the retropatellar region. Etiology is controversial and includes several factors, such as anatomical defects, muscular imbalance, or joint overuse. Good results have been reported with exercise therapy, including home exercise program (HEP). Joint inflammation with increase of pro-inflammatory cytokines levels in the synovial fluid might be seen especially when chondromalacia becomes evident. Biophysical stimulation with pulsed electromagnetic fields (PEMFs) has shown anti-inflammatory effects and anabolic chondrocyte activity. The purpose of this randomized controlled study was to evaluate if the combination of HEP with PEMFs was more effective than HEP alone in PFPS treatment. Thirty-one PFPS patients were enrolled in this study. All patients were instructed to train with HEP. Patients in the PEMFs group associated HEP with PEMFs. Function and pain were assessed with Victorian Institute of Sport Assessment score (VISA), Visual Analog Scale (VAS), and Feller's Patella Score at baseline at 2, 6, and 12 months of follow-up. Drug assumption was also recorded. Increase in VISA score was significantly higher in PEMFs group compared to controls at 6 and 12 months, as well as the increase in the Feller's Patella Score at 12 months. VAS score became significantly lower in the PEMFs group with respect to control group since 6 month follow-up. Pain reduction obtained with PEMFs enhanced practicing therapeutic exercises leading to a better recovery process; this is extremely important in addressing the expectations of young patients, who wish to return to sporting activities.

Predictors of frontal plane knee excursion during a drop land in young female soccer players

STUDY DESIGN

Controlled laboratory study using a cross-sectional, single testing session.

OBJECTIVE

To determine the association between frontal plane knee excursion during a drop land task and measures of hip strength, and ankle and hip range of motion.

BACKGROUND

Assessment of frontal plane knee excursion during a drop land task has been advocated as a means to screen for potentially injurious lower extremity movement patterns. Accordingly, an understanding of the physical characteristics associated with the magnitude of frontal plane knee excursion could assist clinicians in developing interventions and prevention strategies to minimize injury risk.

METHODS AND MEASURES

Thirty-nine female high school soccer players (mean +/- SD age, 15.5 +/- 1.0 years; height, 162.2 +/- 5.3 cm; body mass, 56.8 +/- 6.7 kg) participated. Isometric hip muscle strength as well as ankle and hip range of motion measurements were obtained using standard clinical procedures and a handheld dynamometer. Frontal plane knee excursion was assessed using a 6-camera motion analysis system during a drop land task. Using 3-dimensional coordinate data, maximum frontal plane knee excursion was defined as the difference between the distances of right and left lateral knee markers at initial contact and maximum knee flexion during the deceleration phase of landing. Independent variables found to be significantly correlated with frontal plane knee excursion were then entered into a stepwise multiple regression procedure to determine the best set of predictors of this motion.

RESULTS

Hip external rotation range of motion and ankle dorsiflexion range of motion were found to be negatively correlated with frontal plane knee excursion (r=-0.40, P=.005 and r=-0.27, P=.05, respectively). Together they accounted for 27% of the variance in frontal plane knee excursion (r=0.52, P=.03). No relationships between measures of hip strength and frontal plane knee excursion were found.

CONCLUSIONS

Frontal plane knee excursion during a drop land task was partially attributed to available range of motion at the hip and ankle. These results suggest that range of motion of the joints proximal and distal to the knee should be considered when evaluating individuals who present with excessive frontal plane knee excursion during this task. Given that the relationship between range of motion and frontal plane knee excursion was small, other factors, including learned motor patterns, should be considered.

Overuse injuries in female athletes

The last three decades have witnessed a tremendous increase in female sports participation at all levels. However, increased sports participation of female athletes has also increased the incidence of sport-related injuries, which can be either acute trauma or overuse injuries. Overuse injuries may be defined as an imbalance caused by overly intensive training and inadequate recovery, which subsequently leads to a breakdown in tissue reparative mechanisms. This article will review the most frequent overuse injuries in female athletes in the context of anatomical, physiological, and psychological differences between genders.

Normative three-dimensional patellofemoral and tibiofemoral kinematics: a dynamic, in vivo study

In order to advance biomechanical modeling, knee joint implant design and clinical treatment of knee joint pathology, accurate in vivo kinematic data of the combined patellofemoral and tibiofemoral joint during volitional activity are critical. For example, one cause of the increased prevalence of anterior knee pain in the female population is hypothesized to be altered tibiofemoral kinematics, resulting in pathological patellofemoral kinematics. Thus, the objectives of this paper were to test the hypothesis that knee joint kinematics vary based on gender and to explore the correlation between the 3-D kinematics of the patellofemoral and tibiofemoral joints. In order to accomplish these goals, a large (n = 34) normative database of combined six degree of freedom patellofemoral and tibiofemoral kinematics, acquired noninvasively during volitional knee extension-flexion using fast-PC (dynamic) magnetic resonance imaging, was established. In this normative database, few correlations between tibiofemoral and patellofemoral kinematics were found. Specifically, tibial external rotation did not predict lateral patellar tilt, as has been stated in previous studies. In general, significant differences could not be found based on gender. Further investigation into these relationships in the presence of pathology is warranted.

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 role of hip muscle function in the treatment of patellofemoral pain syndrome

BACKGROUND

Previous literature has associated hip weakness with patellofemoral pain syndrome.

HYPOTHESIS

Improvements in hip strength and flexibility are associated with a decrease in patellofemoral pain.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Thirty-five patients with patellofemoral pain syndrome, aged 33 +mn; 16 years (29 women, 6 men; 43 knees), were evaluated and placed on a 6-week treatment program. Hip flexion, abduction, and adduction strengths, Thomas and Ober test results, and visual analog scale scores for pain with activities of daily living as well as with exercise were documented on initial evaluation and again 6 weeks later. Treatment consisted of strength and flexibility exercises primarily focusing on the hip.

RESULTS

Hip flexion strength improved by 35% +/- 8.4% in 26 lower extremities treated successfully, compared with -1.8% +/- 3.5% in 17 lower extremities with an unsuccessful outcome (P < .001). Before treatment, there were positive Ober test results in 39 of 43 lower extremities; positive Thomas test results were seen in 31 of 43 lower extremities. A successful outcome with a concurrent normalized Ober test result was seen in 83% (20/24) of lower extremities, and successful outcomes with normalized Thomas test results were seen in 80% (16/20) of lower extremities. A combination of improved hip flexion strength (> 20%) as well as normal Ober and Thomas test results was seen in 93% of successfully treated cases (14/15 lower extremities), compared with 0% success (0/5 lower extremities) if there was no change in hip flexion strength (< 20%) and if Ober and Thomas test results remained positive.

CONCLUSIONS

Improvements in hip flexion strength combined with increased iliotibial band and iliopsoas flexibility were associated with excellent results in patients with patellofemoral pain syndrome.

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

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

Issues unique to the female runner

Care and treatment of female runners will improve as further knowledge regarding the unique factors that affect them becomes available. For care and treatment to be their most effective, current and recent information needs to be disseminated among health care providers, coaches, teachers, school administrators, and parents. In young athletes, peer support and education are the most important factors in the success of detection and treatment. Individuals who have the female athlete triad are at significant risk for stress fractures and other injuries. Early detection and multidisciplinary treatment should begin after fractures are detected to reduce or prevent long-term adverse sequelae to bone. In addition, correction of menstrual dysfunction can help to prevent later fertility problems. Addressing the unique biomechanics and core strength of female runners also is essential to rehabilitate athletes past symptom resolution. A thorough understanding of the unique issues for female runners is essential for the prevention of injuries and plays an important role in the promotion of female participation in recreational and competitive running.

Epidemiology of lacrosse injuries in high school-aged girls and boys: a 3-year prospective study

OBJECTIVE

To report the types, mechanisms, and circumstances of lacrosse injuries incurred by high school-aged girls and boys during organized interscholastic and summer camp games.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

For 3 years, the authors gathered data on girls' and boys' lacrosse injuries for 359 040 high school and 28 318 summer camp athletic exposures using a lacrosse-specific computerized injury surveillance system. The most prevalent injuries were organized into multifactorial injury scenarios.

RESULTS

In high school play, the injury rate for adolescent boys (2.89 per 1000 athletic exposures) was slightly higher than that for girls (2.54 per 1000 athletic exposures) (incidence rate ratio = 1.14; 95% confidence interval, 1.00-1.30). The most prevalent injuries for adolescent girls and boys were knee and ankle sprains resulting from noncontact mechanisms. Male players had significantly higher rates of shoulder, neck, trunk, and back injuries and higher game-to-practice injury ratios. In addition, they had higher rates of concussive events from player-to-player contact. Female players had higher rates of overall head injuries, many involving contusions and abrasions from stick and ball contact.

CONCLUSIONS

The overall injury rates for boys' and girls' high school lacrosse were significantly lower than those for collegiate play. Significant differences existed between adolescent boys and girls with respect to injury mechanisms, body parts injured, and player and team activity at the time of injury.

Avaliação eletromiográfica dos músculos estabilizadores da patela durante exercício isométrico de agachamento em indivíduos com síndrome da dor femoropatelar

O objetivo deste trabalho foi comparar a atividade elétrica dos músculos vasto medial oblíquo (VMO), vasto lateral longo (VLL) e vasto lateral oblíquo (VLO) durante os exercícios isométricos de agachamento wall slide a 45º (WS 45º) e 60º (WS 60º) de flexão do joelho. Foram avaliadas 15 mulheres clinicamente saudáveis e 15 mulheres com síndrome da dor femoropatelar (SDFP). Os registros eletromiográficos foram obtidos por eletrodos ativos simples conectados a um eletromiógrafo durante a contração isométrica voluntária máxima (CIVM) do WS 45º e WS 60º. Os dados foram analisados pela média dos valores do root mean square (RMS) do sinal eletromiográfico, normalizado pela média do RMS obtido no agachamento a 75º de flexão do joelho. A análise estatística empregada foi o teste ANOVA two way (p < 0,05) e teste de Duncan post hoc (p < 0,05). Os resultados revelaram que o exercício WS 60º apresentou maior atividade elétrica nos músculos VMO, VLL e VLO quando comparado com o WS 45º, para os grupos controle e SDFP. Durante o WS 60º, para o grupo controle, não foram observadas diferenças na atividade dos músculos VMO, VLO e VLL, sugerindo um equilíbrio na atividade elétrica destes músculos, enquanto que no WS 45º o músculo VLL apresentou maior ativação quando comparado com os músculos VMO e VLO. Para o grupo SDFP, esse equilíbrio entre as porções medial e lateral do músculo quadríceps foi observado em ambos os exercícios. Esses dados sugerem que WS 60º, para o grupo controle, pode ser mais efetivo para programas de fortalecimento muscular. Contudo, para o grupo com SDFP, ambos os exercícios podem ser indicados durante o programa de reabilitação. Além disso, a ausência de diferenças na atividade eletromiográfica dos músculos VMO, VLO e VLL entre os grupos, neste estudo, sugere que o desequilíbrio muscular pode não ser um fator predisponente da SDFP.

Common athletic injuries in adolescent girls

Teenaged girls constitute the fastest growing segment of children and adolescents participating in organized athletics. Adolescent girls appear to have similar injury rates as boys in comparable activities but different injury patterns. To properly diagnose and manage athletic injuries in adolescent girls, pediatric health care providers must be aware of these differences, especially as the literature and their knowledge base may be skewed to the traditional predominance of males in sport. This review identifies athletic injuries that are unique to or especially common in adolescent girls, including apophyseal injuries; breast and pelvic injuries; scoliosis and spondylolysis; multidirectional shoulder instability and "gymnast's wrist"; anterior cruciate ligament injuries and patellofemoral pain syndrome; chronic exertional lower-leg compartment syndrome, ankle sprains, and reflex sympathetic dystrophy; and stress fractures. It also briefly discusses possible risk factors for these injuries, emphasizing the female athlete triad.