Patellar Tendon Abnormalities Research Articles

Association Between Patellar Tendon Abnormality and Land-Jump Biomechanics in Male Collegiate Basketball Players During the Preseason.

Patellar tendinopathy is a degenerative condition that predominantly affects jumping athletes. Symptoms may be subtle or nonexistent at preseason, but structural abnormalities may be present. Assessing patellar tendon abnormality (PTA) through magnetic resonance imaging (MRI) and ultrasound (US) and classifying symptoms using the Victorian Institute for Sport Assessment-Patellar tendon (VISA-P) may provide useful insights if combined with biomechanics measurements. To (1) assess whether land-jump biomechanical patterns are associated with clinically pertinent PTA as seen on imaging and through VISA-P scores and (2) model the contributing risk and accuracy of biomechanics to classify PTA and symptomatic observations. Cross-sectional study; Level of evidence, 3. A total of 26 National Collegiate Athletic Association Division I and II male basketball players (n = 52 limbs) were recruited during the preseason. We collected VISA-P scores, bilateral PTA through US and MRI morphology measurements, and bilateral 3-dimensional lower extremity kinematics and kinetics measurements from a land-jump test from an 18-inch-high (45.7-cm-high) box. Statistically, each limb was treated independently. The association of biomechanics with PTA and symptoms (VISA-P score <80) was tested with multivariate models and post hoc tests. Logistic regression modeled relative risk and accuracy of biomechanical variables to classify PTA and symptomatic limbs. There were 19 to 24 limbs with PTA depending on US and MRI measurements. Differences in hip and knee kinematic strategies and ground-reaction loads were associated with PTA and symptomatic limbs. Peak landing vertical ground-reaction force was significantly decreased (169 ± 26 vs 195 ± 29 %body weight; P = .001), and maximum hip flexion velocity was significantly increased (416 ± 74 vs 343 ± 94 deg/s; P = .005) in limbs with versus without PTA on imaging. Knee flexion at the initial contact was decreased in symptomatic versus healthy limbs (17°± 5° vs 21°± 5°, respectively; P = .045). Regression models classified PTA limbs and symptomatic limbs with 71.2% to 86.5% accuracy. Hip and knee maximum flexion velocity and vertical ground-reaction force variables were most common across models observing clinically pertinent PTA. Our findings suggested that functional kinematic and kinetic biomechanical strategies at the hip and knee were associated with PTA, identified on imaging, and symptomatic limbs.

Prevalence of Sonographic Achilles Tendon, Patellar Tendon, and Plantar Fascia Abnormalities in Division I Collegiate Athletes From a Variety of Sports.

This study aimed to determine the prevalence of ultrasound abnormalities in the Achilles tendon, patellar tendon, and plantar fascia among a large cohort of collegiate student-athletes. Observational cross-sectional study. Three Division I institutions. 243 student-athletes participated in this study. Exclusion criteria included those younger than 18 years or who underwent prior surgery/amputation of structures, including anterior cruciate ligament (ACL) surgeries with patellar tendon grafts. Ultrasound examination of the Achilles tendon, patellar tendon, and plantar fascia of each leg was performed. An experienced sonographer reviewed each tendon video in a blinded manner, with a separate experienced sonographer separately reviewing to establish inter-rater reliability. The primary outcome measured was the presence of any sonographic abnormality including hypoechogenicity, thickening, or neovascularity. Ultrasound abnormalities were identified in 10.1%, 37.2%, and 3.9% of all Achilles tendons, patellar tendons, and plantar fasciae, respectively. Abnormalities were significantly associated with the presence of concurrent pain for all structures ( P < 0.01). Specifically, athletes with sonographic abnormalities were approximately 4 times [relative risk (RR) = 4.25; 95% confidence interval (CI), 2.05-8.84], 6 times (RR = 5.69; 95% CI, 2.31-14.00), and 5 times (RR = 5.17; 95% CI, 1.76-15.25) more likely to self-report pain in the Achilles tendon, patellar tendon, and plantar fascia, respectively. This multi-institutional study completed at 3 Division I institutions is the largest study of its kind to identify the prevalence of sonographic abnormalities in the Achilles tendon, patellar tendon, and plantar fascia among collegiate student-athletes of various sports.

Proximal patellar tendon abnormalities on ultrasound can develop in male adolescent basketball players: A longitudinal study

IntroductionAdolescent patellar tendinopathy is reported but the pubertal-stage of onset of abnormal tendon structure has not been investigated with grayscale ultrasound. AimsTo investigate abnormal tendon structure using grayscale ultrasound and its association with pubertal-stage and pain. MethodsForty-three male basketball players aged 13.7 years (SD 1.0) had patellar tendon ultrasound scans every 6 months for 2.5 years. Pubertal-stage (peak height velocity) was calculated using the Mirwauld equation. Tendon thickness, hypoechogenicity and pain during single leg decline squat (SLDS) were recorded. Tendons were classified: hypoechoic, normal or immature. ResultsTwo tendons were hypoechoic at baseline. Six developed hypoechogenicity over 2.5 years (eight tendons [9%], six participants [14%]), all in peri and post-PHV players. Twenty-six tendons (17 participants) were classified as immature during the study. Hypoechoic tendons were thicker (5.3 mm SD 1.2) than normal (3.9 mm SD 0.7) tendons (p < 0.001). There was no difference in the proportion of participants reporting pain during SLDS in the hypoechoic (N = 3) and normal (N = 11) groups (p = 0.33), or in hypoechoic tendon thickness between those reporting pain (6.5 mm, SD 1.7) or not (5.2 mm, SD 0.9, p = 0.17). DiscussionThis study using grayscale ultrasound found that basketball players with hypoechogenicity were peri or post-PHV. Abnormal structure was not always associated with pain.

Male and female adolescent athletes develop patellar tendon abnormalities at different maturity stages: a longitudinal study of 173 athletes

Introduction: Patellar tendon abnormalities have been reported to occur in adolescent athletes who load the patellar tendon. The adolescent growth spurt has been suggested as a critical time-point for the formation of a healthy patellar tendon. Presence of a patellar tendon abnormality has been identified as a risk factor for the development of pain and dysfunction in later life. This longitudinal study aims to investigate factors associated with the development of patellar tendon abnormality during the critical time period of adolescence.

Disorganised patellar tendon structure remains inert despite continued exposure to high loading environments

Introduction: Ultrasound tissue characterisation (UTC) is a unique imaging modality used to investigate structural changes of the patellar tendon. Adolescent athletes who load their knees may be susceptible to patellar tendon abnormality(s) (PTA), characterised by areas of structural disorganisation. Presence of a PTA is a risk factor for the development of pain and dysfunction. This longitudinal study aimed to investigate patellar tendon structural changes in adolescent athletes with PTA.

MO804: Clinical and Ultrasonographic Features of 104 Knee Joints in Haemodialysis Patients and Their Association with Semiquantitative Measurement of Suprapatellar Effusion and Influence of Age, Gender and Duration of Haemodialysis

Abstract BACKGROUND AND AIMS Musculoskeletal disorders remain a major problem in haemodialysis (HD) patients. The aim of this study was to determine knee clinical and ultrasonographic (US) abnormalities in HD patients to evaluate the influence of age, gender and HD duration. METHOD This cross-sectional descriptive study was conducted on 52 patients (104 knee joints) who had been on regular HD for at least 6 months. Demographic, clinical, therapeutic and laboratory data were recruited. Participants were questioned about the presence of chronic knee pain and its duration, severity and laterality. Both knees were evaluated for the presence of joint swelling, crepitus and tenderness. All patients underwent musculoskeletal (MSUS) evaluation of both knees, which was conducted according to EULAR standardized procedures. MSUS was used to determine the presence of suprapatellar effusion, synovial thickening and Baker's cyst and to detect any abnormalities in the cartilage morphology. Quadriceps and patellar tendons and menisci were also sonographically assessed. Cartilage thickness was measured bilaterally from the central points of the medial condyle and lateral condyle patients were then compared according to age, gender and HD duration. RESULTS The mean age of the patients was 52.4 ± 14.15 years, 25 females and 27 males, and the median duration of HD was 3.5 (0.6–13) years. Chronic knee pain was present in 31/104 (29.8%) knees. Among the scanned 104 knee joints, there was at least one US abnormality in 91 (87.5%); suprapatellar effusion was found in 57 (54.8%), synovial thickening in 13 (12.5%), abnormal cartilage morphology in 68 (65.4%), quadriceps tendon abnormalities in 58 (55.8%), patellar tendon abnormalities in 34 (32.7), medial meniscus abnormalities in 30 (28.8%), lateral meniscus abnormalities in 13 (12.5%) and Baker’s cyst in 5 (4.8%) (Fig. 1). MSUS abnormalities were significantly more frequent in HD patients aged &amp;gt;40 years (94.9% versus 65.4; P = .000) than others. Chronic knee pain and abnormal cartilage morphology were more likely to occur in females (40% versus 20.4% and 74.1% versus 56%, respectively) than in males (Fig. 2). According to HD duration, quadriceps and patellar tendons showed more frequent US abnormalities in patients with HD duration &amp;gt; 3 years (86.5% versus 42% and 38.9% versus 26%, respectively) than in others. The prevalence of mild, moderate and severe suprapatellar effusion was 37.5%, 14.4% and 2.9%, respectively. There was a significant association between semiquantitative measurement of suprapatellar effusion and synovial thickening (P = .000), abnormal cartilage morphology (P = 0.023), quadriceps (0.002) and patellar tendon abnormalities (0.011) (Table 1). CONCLUSION Knee US abnormalities are prevalent among HD patients, especially those with female gender, older age and higher HD duration. These abnormalities may be subclinical. The severity of suprapatellar effusion is usually related to other knee structural abnormalities.

Physical Activity and Investigation With Magnetic Resonance Imaging Partly Explain Variability in the Prevalence of Patellar Tendon Abnormalities: A Systematic Review With Meta-analysis of Imaging Studies in Asymptomatic Individuals.

To estimate the pooled prevalence of, and factors associated with, the presence of patellar tendon abnormalities observed on imaging in people without symptoms. Systematic review with stratified meta-analysis and meta-regression. We searched Embase, Scopus, MEDLINE, CINAHL, SPORTDiscus, and Web of Science from 1980 to August 2020. We included studies that reported the prevalence of asymptomatic patellar tendon abnormalities on imaging. We excluded studies of participants with current tendon pain, a history of tendon pain, or other systemic conditions. Stratification and meta-regression of studies based on study-level descriptive statistics (mean age, body mass index, proportion of female participants, physical activity participation, imaging modality) were performed using a random-effects model to account for between-study heterogeneity. Risk of bias was assessed using the modified Newcastle-Ottawa scale. Meta-analysis of 64 studies (7125 limbs from 4616 participants) found significant between-study heterogeneity (I2≥90%, P<.01), which precluded a summary prevalence estimate. Heterogeneity was partially explained by studies that included participants who were physically active and studies that assessed tendon abnormalities using magnetic resonance imaging compared to ultrasound (P<.05). Mean age, body mass index, proportion of female participants, and sample size did not explain the remaining heterogeneity. There was substantial variability in the reported prevalence of asymptomatic patellar tendon abnormalities. A clear and valid method is needed to assess and report the presence of patellar tendon abnormalities to increase research capacity and establish the clinical value of imaging the patellar tendon. J Orthop Sports Phys Ther 2021;51(5):216-231. Epub 28 Mar 2021. doi:10.2519/jospt.2021.10054.

Self-reported jumpers’ knee is common in elite basketball athletes – But is it all patellar tendinopathy?

ObjectivesTo describe the prevalence and pain location of self-reported patellar tendinopathy and patellar tendon abnormality in a male elite basketball population. DesignCross-sectional. SettingPre-season tournament. ParticipantsSixty male athletes from the Australian National Basketball League. Main outcome measuresSelf-reported patellar tendinopathy (PT) using the Oslo Sports Trauma Research Centre Overuse Questionnaire (OSTRC). Pain location using pain mapping (dichotomised: focal/diffuse) and severity during the single leg decline squat. Ultrasound tissue characterisation scans of both patellar tendons. ResultsThirteen participants (22.7%) self-reported PT. Only 3 who reported PT had localised inferior pole pain. Thirty athletes reported pain during the decline squat, 15 described focal pain; 10 diffuse pain (5 missing data). Those with diffuse pain had greater years played [Md = 21 (13–24), n = 10 than focal pain (Md = 12 (7–26), n = 15), p = 0.042, r = 0.3]. Bilateral tendon abnormality was found in 45% of athletes and 15% had unilateral tendon abnormality. ConclusionElite male basketball athletes self-reporting PT had heterogeneity in pain location. When focal pain with loading was used as a primary definition of PT, ‘jumpers’ knee’ was not common in this cohort. This study found that abnormality of the patellar tendon was common and did not correlate with symptoms.

Jump-landing mechanics in patellar tendinopathy in elite youth basketballers.

Patellar tendinopathy (PT) is a leading cause of morbidity in jump-landing athletes. Landing mechanics are identified as a factor associated with PT and/or patellar tendon abnormality. This study aimed to identify key jump-landing variables associated with PT. Thirty-six junior elite basketball players (men n=18, women n=18) were recruited from a Basketball Australia development camp. Three-dimensional (3D) kinematic and ground reaction force (GRF) data during a stop-jump task were collected as well as ultrasound scans of the patellar tendons and recall history of training load data. Mixed-model factorial analyses of variance were used to determine any significant between-group differences. Of the 23 participants included for statistical analyses, 11 had normal bilateral patellar tendons (controls) and eight reported PT (currently symptomatic); however, the four participants categorized as asymptomatic with patellar tendon abnormality on diagnostic imaging were excluded from statistical analyses due to their small sample size. Athletes with PT displayed a similar knee flexion angle at initial foot-ground contact (IC) and hip extension strategy during a stop-jump horizontal landing. Despite a similar kinematic technique, athletes with PT utilized a strategy of a longer stance duration phase from IC to peak force. This strategy did not lead to those athletes with PT decreasing their peak vertical GRF nor patellar tendon force during landing but enabled these athletes to land with a lower rate of loading (control 59.2 ± 39.3 vs. PT 29.4 ± 33.7 BW.s-1). Athletes with PT still reported significantly reduced training volume (control 4.9±1.8 vs PT 1.8±1.1 sessions/wk; total training time/wk control 2.4±1.0 vs PT 1.4±1.1h/wk).

Landing Biomechanics, But Not Physical Activity, Differ in Young Male Athletes With and Without Patellar Tendinopathy.

To examine differences in biomechanical and physical activity load in young male athletes with and without patellar tendinopathy. Cross-sectional cohort study. Forty-one young male athletes (15-28 years of age) were categorized into 3 distinct groups: symptomatic athletes with patellar tendon abnormalities (PTA) (n = 13), asymptomatic athletes with PTA (n = 14), and a control group of asymptomatic athletes without PTA (n = 14). Participants underwent a laboratory biomechanical jump-landing assessment and wore an accelerometer for 1 week of physical activity monitoring. The symptomatic group demonstrated significantly less patellar tendon force loading impulse in the involved limb compared with both the control and asymptomatic groups (P<.05), with large effects (d = 0.91-1.40). There were no differences in physical activity between the 3 groups (P>.05). Young male athletes with symptomatic patellar tendinopathy demonstrated smaller magnitudes of patellar tendon force loading impulse during landing compared to both asymptomatic athletes with patellar tendinopathy and healthy control participants. However, these 3 distinct groups did not differ in general measures of physical activity. Future investigations should examine whether comprehensively monitoring various loading metrics may be valuable to avoid both underloading and overloading patterns in athletes with patellar tendinopathy. J Orthop Sports Phys Ther 2020;50(3):158-166. Epub 6 Jan 2020. doi:10.2519/jospt.2020.9065.

Low prevalence of patellar tendon abnormality and low incidence of patellar tendinopathy in female collegiate volleyball players

ABSTRACTThe prevalence of patellar tendinopathy has been reported to be as high as 50% in elite male volleyball (VB) players; however, the rate of injury in female collegiate VB athletes is unknown. The purpose of this study was to 1) identify the prevalence of ultrasonographic evidence of patellar tendon abnormality at the start of the preseason in female collegiate VB players; 2) report the incidence of tendinopathy during the season; and 3) determine if the preseason presence of tendon abnormality is associated with onset of disease. One hundred and six female collegiate VB players had both patellar tendons imaged. Incidence of patellar tendinopathy was tracked during the course of the 4-month season. Twenty-two athletes presented with ultrasonographic evidence of patellar tendon abnormality in at least one knee at the start of the preseason. The incidence of time-loss patellar tendinopathy was 0.26 (95% CI: 0.04, 0.85) per 1000 athletic exposures. This study was unable to determine if preseason presence of tendon abnormality was associated with a greater risk of tendinopathy due to power. The prevalence of tendon abnormality in the preseason and the incidence of patellar tendinopathy in female collegiate VB players are lower than that observed in other populations.

Prevalence of Patellar Tendinopathy and Patellar Tendon Abnormality in Male Collegiate Basketball Players: A Cross-Sectional Study.

Patellar tendinopathy (PT) is a degenerative condition known to affect athletes who participate in sports such as basketball and volleyball. Patellar tendinopathy is a challenging condition to treat and may cause an athlete to prematurely retire from sport. The prevalence of PT in male collegiate basketball players is unknown. To determine the prevalence of PT and patellar tendon abnormality (PTA) in a population of male collegiate basketball players. Cross-sectional study. National Collegiate Athletic Association Divisions II and III, National Association of Intercollegiate Athletics, and Northwest Athletic Conference male collegiate basketball teams were assessed in a university laboratory setting. Ninety-five male collegiate basketball players (age = 20.0 ± 1.7 years). A diagnostic ultrasound image of an athlete's patellar tendon was obtained from each knee. Patellar tendinopathy was identified based on a player's symptoms (pain with palpation) and the presence of a hypoechoic region on an ultrasonographic image. A majority of participants, 53 of 95 (55.8%), did not present with pain during palpation or ultrasonographic evidence of PTA. Thirty-two basketball players (33.7%) displayed ultrasonographic evidence of PTA in at least 1 knee; 20 of those athletes (21.1%) had PT (pain and tendon abnormality). Nonstarters were 3.5 times more likely to present with PTA (odds ratio = 3.5, 95% confidence interval = 1.3, 9.6; P = .017) and 4 times more likely to present with PT (odds ratio = 4.0, 95% confidence interval = 1.1, 14.8; P = .038) at the start of the season. One in 3 male collegiate basketball players presented with either PT or PTA. Sports medicine professionals should evaluate basketball athletes for PT and PTA as part of a preseason screening protocol.

Knee Ultrasonography to Determine Risk for Noncontact Injuries in Collegiate American Football Players.

Knee ultrasonography has been used effectively as a screening tool for determining risk for knee injuries in athletes. Ultrasonography may be a valuable screening tool for relative risk of noncontact knee injuries that occur over a typical playing career in collegiate American football players. In this prospective longitudinal study, we evaluated American football players (n = 48) in an academic institution affiliated with the National Collegiate Athletic Association Division I athletic program. Players underwent comprehensive ultrasonography of both knees prior to beginning their collegiate careers. Anatomic structures were evaluated for presence and severity of abnormalities. Noncontact lower extremity injuries sustained over the collegiate career of the subjects were documented. Data were analyzed for correlations, differences in proportions, and odds ratio (OR). Seventy-nine percent of the athletes had at least one ultrasonographic abnormality, with quadriceps tendon (47.9%) and patellar tendon (39.6%) abnormalities predominating. Seventy-nine percent of players had at least one noncontact lower extremity injury (23.5% involving the knee) during their careers with an average of 2.8 injuries per career. The majority of injuries occurred in the second and third playing years. There was a significantly higher likelihood of patellar tendon injury based on the presence of patellar tendon ultrasonographic pathology (p = 0.024; OR = 11x). There was a significantly higher likelihood of quadriceps muscle-tendon injury based on the presence of quadriceps tendon ultrasonography pathology (p = 0.0012; OR = 140x). All athletes sustaining meniscal injuries had preexisting joint effusion but no preexisting ultrasonographic meniscal pathology. Knee ultrasonography along with patient history and complete physical examination may help reduce injury risk through education, prevention, and training programs.

Association Between Self-reported Measures, Physical Examination, and Early Magnetic Resonance Imaging Signs of Osteoarthritis in Patients With Patellofemoral Pain.

Structural abnormalities associated with osteoarthritis (OA) are found in some patients with patellofemoral pain (PFP). To investigate the association between early signs of OA on magnetic resonance imaging (MRI) and characteristics from self-reported measures and physical examination in patients with PFP. This exploratory study included data from patients with PFP from a previously published cross-sectional case-control study (n = 64; 55% female; mean ± SD age, 23.4 ± 7.0 years). Structural OA features (osteophytes, bone marrow lesions, cartilage defects, Hoffa synovitis, patellar tendon abnormalities) and quantitative T2 measurements of cartilage composition were extracted from MRI. Associations between characteristics from self-reported measures (pain at rest, pain during stair walking, knee function, duration of complaints, hours of sports participation each week), physical examination (crepitus, quadriceps strength), and early MRI signs of OA were assessed. Symptom duration was associated with bone marrow lesions in the patella (odds ratio [OR] = 1.1; 95% confidence interval [CI]: 1.0, 1.2). Sports participation (hours per week) was inversely associated with patellar tendon abnormalities on MRI (OR = 0.8; 95% CI: 0.6, 1.0). Crepitus and bilateral nature of the complaints were associated with minor patellar cartilage defects (OR = 12.0; 95% CI: 2.3, 63.6 and OR = 7.6; 95% CI: 1.1, 53.8, respectively). There were no significant associations between clinical characteristics and cartilage T2 relaxation time. Presence of crepitus, bilateral complaints, a long PFP symptom duration, and reduced weekly sport participation were associated with early signs of OA in a young PFP population. Etiology, level 2c. J Orthop Sports Phys Ther 2019;49(9):634-639. Epub 10 Jul 2019. doi:10.2519/jospt.2019.8889.

A Novel Method for Assessing Regional Tendon Stiffness and Its Significance

Elastography can be used to estimate the regional shear modulus of a tendon. This can advance our knowledge on the impact of patellar alignment and regional patellar tendon stiffness. This is important as patellar tendon abnormality is mainly found in the medial portion of the tendon in subjects with proximal patellar tendinopathy. This paper aims to assess the effect of patellar displacement on differential modulation on the shear modulus of the patellar tendon. Shear modulus is captured on the medial and lateral half of the patella tendon using the Axiplorer® ultrasound unit in conjunction with a 4–15 MHz, 50 mm linear transducer with the patellar being positioned in its resting, medio- and laterally displaced positions on 40 adults (19 females, 21 males). When the patellar is displaced laterally, the shear modulus is significantly increased at the medial half in both genders but decreased at the lateral half only in females. Conclusions: Elastography detects changes in regional tendon stiffness associated with alteration in patellar positions. The modulation on the shear modulus is gender and region specific.

Effects of Altering Trunk Position during Landings on Patellar Tendon Force and Pain.

This study aimed to verify the immediate effects of altering sagittal plane trunk position during jump landings on lower limb biomechanics, patellar tendon force, and pain of athletes with and without patellar tendinopathy. Twenty-one elite male athletes were categorized into three groups: athletes with patellar tendinopathy (TG; n = 7), asymptomatic athletes with patellar tendon abnormalities (n = 7), and asymptomatic athletes without tendon abnormalities (CG; n = 7). A biomechanical evaluation was conducted while the athletes performed drop landings from a bench in a self-selected trunk position (SS). Afterward, the athletes were randomly assigned to land with either a flexed trunk position (FLX) or an extended trunk position (EXT). Variables of interest for this study included sagittal plane peak kinematics, kinetics, patellar tendon force, and pain during the landing tasks. Peak patellar tendon force, knee extensor moment, and knee pain decreased in the FLX landing compared with the SS landing, regardless of group. In addition, peak patellar tendon force, knee extensor moment, and vertical ground reaction force were smaller in the FLX landing compared with the EXT landing. The TG had smaller peak ankle dorsiflexion compared with the CG during jump landings, regardless of trunk position. Landing with greater trunk flexion decreased patellar tendon force in elite jumping athletes. An immediate decrease in knee pain was also observed in symptomatic athletes with a more flexed trunk position during landing. Increasing trunk flexion during landing might be an important strategy to reduce tendon overload in jumping athletes.

Quantitative analysis of patellar tendon size and structure in asymptomatic professional players: sonographic study.

Ultrasonographic abnormalities of the patellar tendon frequently occur in asymptomatic athletes and it is not always clear whether they precede (and may predict) the development of tendinopathy. This study aimed to investigate by ultrasonography the prevalence of patellar tendon abnormalities in players of "pallapugno" and to establish whether structural tendon abnormalities predict tendinopathy development. Ultrasound B-mode images of the patellar tendon of both sides were acquired in fourteen throwers. Qualitative assessments of tendon structure and neovascularization and quantitative assessments of tendon thickness, cross sectional area (CSA), and echo-intensity were performed. Qualitative assessments showed a subclinical tendinopathy of the non-dominant tendon in 5 out of 14 throwers (35% of cases), while quantitative assessments showed abnormalities of the non-dominant tendon in 8 out of 14 players (57% of cases). Echo-intensity and CSA were the quantitative variables most discriminant between asymptomatic players without structural tendon abnormalities and those with tendon abnormalities. Two players (2 out of 8 cases: 25%) developed a clinical tendinopathy after a follow-up of six months. The prevalence of subclinical tendinopathy in the non-dominant patellar tendon of throwers was high. Patellar tendon abnormalities at baseline seem to increase the risk of development of subsequent patellar tendinopathy. II b (individual cohort study).

Assessment of anterior subcutaneous hypersignal on proton-density-weighted MR imaging of the knee and relationship with anterior knee pain

The purpose of this study was to evaluate the prevalence of anterior subcutaneous hypersignal indicating edema on proton-density (PD)-weighted MRI of the knee and to determine whether reporting anterior edema is clinically relevant. One hundred and ninety-one knee MRIs from 162 patients were reviewed for anterior subcutaneous edema. There were 92 men and 70 women with a mean age of 41.72years±13.92 (SD) (range, 15-80years) years and a mean body weight of 75.94kg±12.54 (SD) (range, 50-130kg). The MRI findings were compared with patient age, gender, body weight, history of repetitive microtrauma and clinical findings. Patellar and trochlear chondropathy, medial plica, joint effusion, synovitis, infrapatellar fat-pad signal intensity, suprapatellar fat-pad signal intensity with mass effect, quadriceps and patellar tendon abnormalities were also reviewed. An anterior hypersignal on PD-weighted MRI was detected in 158/191 MR examinations (82.7%) and 104 (84.6%) of these cases had histories of anterior knee pain. No correlation between anterior pain and anterior edema was found (P=0.42). Age (P<0.0001), weight (P<0.0001), and repetitive microtrauma (P=0.001) were identified as significant variables associated with anterior edema. Anterior edema may be a physiological phenomenon or degenerative change related to patient age, weight, and knee movement or mechanics. It should not be reported as a pathological finding on MRI unless clinical findings support regional infection or inflammation.

Asymptomatic players with a patellar tendon abnormality do not adapt their landing mechanics when fatigued

ABSTRACTThis study aimed to explore how asymptomatic athletes with a patellar tendon abnormality (PTA), who are at high risk of developing patellar tendinopathy, alter their landing technique and net patellar tendon loads generated in response to fatigue. Seven asymptomatic players with a PTA performed five successful vertical stop-jump trials before and after a fatigue protocol. Fatigue protocol involved participants repeatedly performing sets of 30 submaximal jump exercises on a sledge apparatus followed by 30 s rest until the task failure criteria were reached. Three-dimensional ground reaction forces, lower limb kinematics and net peak patellar tendon force were recorded during the stop-jump task. No significant between-fatigue condition differences in net patellar tendon loading, or most secondary outcome variables were observed. Only some fatigue changes were seen during the vertical landing phase. Asymptomatic PTA participants did not modify their landing technique or net patellar tendon loading during a stop-jump task in response to fatigue. The lack of between-fatigue condition differences displayed by the asymptomatic PTA participants during both landing phases suggest that these individuals may not be capable of sufficient movement variability in their landing strategies to adapt to fatigue.

Preventive interventions for tendinopathy: A systematic review.

Tendinopathy, the most prevalent tendon disorder which is considered as the clinical diagnosis of pain and dysfunction, is common in sports and its prevalence is ever-increasing. Despite the lack of clarity about risk factors, various preventive interventions for tendinopathy have been investigated. The main objective of this study is to review current preventive interventions for tendinopathy in the major regions: ankle, knee, hip, groin, shoulder and elbow. A systematic literature search was conducted. The PubMed and Embase databases were explored to identify articles that met the inclusion criteria. The included studies were assessed on methodological quality and data was summarized. Ten articles were included that describe a wide variety of preventive interventions. These were divided into three categories: stretch and exercise interventions, shoe adaptations and other interventions. The methodological quality of the studies was moderate to high. Three out of ten studies showed a significant beneficial result. There is limited evidence that a long-term intervention including balance training is effective in the prevention of patellar and Achilles tendinopathy. Shoe adaptations in the form of shock absorbing insoles could have a preventive effect on Achilles tendinopathy. Hormone replacement therapy seems to reduce the risk for structural Achilles tendon changes in active post-menopausal women. No evidence was found for a positive effect of stretching exercises. Prophylactic eccentric training and stretching can increase the risk of injury in asymptomatic players with patellar tendon abnormalities. A limited amount of studies was available and more research is needed on (multifactorial) etiology, risk factors and preventive interventions.