Patellofemoral pain syndrome (PFPS): a systematic review of anatomy and potential risk factors

Patellofemoral Pain Syndrome (PFPS), a common cause of anterior knee pain, is successfully treated in over 2/3 of patients through rehabilitation protocols designed to reduce pain and return function to the individual. Applying preventive medicine strategies, the majority of cases of PFPS may be avoided if a pre-diagnosis can be made by clinician or certified athletic trainer testing the current researched potential risk factors during a Preparticipation Screening Evaluation (PPSE). We provide a detailed and comprehensive review of the soft tissue, arterial system, and innervation to the patellofemoral joint in order to supply the clinician with the knowledge required to assess the anatomy and make recommendations to patients identified as potentially at risk. The purpose of this article is to review knee anatomy and the literature regarding potential risk factors associated with patellofemoral pain syndrome and prehabilitation strategies. A comprehensive review of knee anatomy will present the relationships of arterial collateralization, innervations, and soft tissue alignment to the possible multifactoral mechanism involved in PFPS, while attempting to advocate future use of different treatments aimed at non-soft tissue causes of PFPS

Adolescent differences in knee stability following computer-assisted anterior cruciate ligament reconstruction

<div class="page" title="Page 1"><div class="section"><div class="layoutArea"><div class="column"><p><span>Anterior cruciate ligament (ACL) surgery is being increasingly performed in the adolescent population. Computer navigation offers a reliable way to quantitatively measure knee stability during ACL reconstruction. A retrospective review of all adolescent patients (&lt;18 years old) who underwent computer-assisted primary single bundle ACL reconstruction by a single surgeon from 2007 to 2012 was performed. The average age was 15.8 years (SD 3.3). Female adolescents were found to have higher internal rotation than male adolescents both pre- (25.6° </span><em>vs </em><span>21.7°, P=0.026) and post-reconstruction (20.1° </span><em>vs </em><span>15.1°, P=0.005). Compared to adults, adolescents demonstrated significantly higher internal rotation both pre- (23.3° </span><em>vs </em><span>21.5°, P=0.047) and post-reconstruction (17.1° </span><em>vs </em><span>14.4°, P=0.003). They also had higher total rotation both pre- (40.9° </span><em>vs </em><span>38.4°, P=0.02) and post-reconstruction when compared to adults (31.56° </span><em>vs </em><span>28.67°, P=0.005). In adolescent patients, anterior translation was corrected more than rotation. Females had higher pre- and residual post-reconstruction internal rotation compared to males. When compared to adults, adolescents had increased internal rotation and total rotation both pre- and post-reconstruction. </span></p></div></div></div></div

Portable dynamic ultrasonography is a useful tool for the evaluation of suspected syndesmotic instability: a cadaveric study

Purpose: Portable ultrasonography (P-US) is increasingly used to diagnose syndesmotic instability. The aim of this study was to evaluate syndesmotic instability by measuring the distal tibiofibular clear space (TFCS) in a cadaveric model using P-US with progressive stages of syndesmotic ligamentous transection under external rotation stress. Methods: Ten fresh lower leg cadaveric specimens amputated above the proximal tibiofibular joint were used. Using P-US, the TFCS was evaluated in the intact stage and after progressive sectioning of the (1) anterior–inferior tibiofibular ligament (AITFL), (2) interosseous ligament (IOL), and (3) posterior–inferior tibiofibular ligament (PITFL). The TFCS was measured in both the unstressed (0 Nm) state and with 4.5, 6.0, 7.5, and 9.0 Nm of external rotation stress using a bone hook placed on the first metatarsal bone at each stage of ligamentous transection stage using both P-US and fluoroscopy. Results: When assessed with P-US, partial syndesmotic injury encompassing the AITFL and IOL resulted in significant TFCS widening at 4.5 Nm of external rotation torque when compared to intact state with a TFCS-opening of 2.6 ± 2 mm, p = 0.01. In contrast, no significant differences in TFCS were detected using fluoroscopy. Only a moderate correlation was found between P-US and fluoroscopy. Conclusion: P-US is a useful tool in diagnosing syndesmotic instability during external rotation stress examination. TFCS-opening increased as additional ligaments of the syndesmosis were transected, and application of 4.5 Nm torque was sufficient to detect a difference of 2.6 mm after the IOL cut

Diagnosing syndesmotic instability with dynamic ultrasound – establishing the natural variations in normal motion

Background: Syndesmotic instability, when subtle, is challenging to diagnose and often requires visualization of the syndesmosis during applied stress. The primary aim was to assess normal distal tibiofibular motion in the sagittal plane using dynamic ultrasound under stress conditions. The secondary aim was to evaluate the reliability of dynamic stress ultrasonography. Methods: Twenty-eight participants without history of ankle injury were included. Sagittal fibular translation was generated by applying a manual force to the fibula from anterior to posterior and from posterior to anterior. Distance between the ultrasound probe and the fibula was taken at two predefined points: 1) no force applied and, 2) during maximum force application. Each participant was scanned twice by two independent examiners, and each scan was analysed by two independent examiners. Three participants were scanned a second time by the same examiner who analysed these films twice to assess for intraobserver agreement. Means of exam 1 versus exam 2 were compared using a mixed linear model. Agreement among observers was calculated using intraclass correlation coefficients (ICC) interpreted as 0.4, poor; 0.4 〈 ICC < 0.59, acceptable; 0.6 < ICC < 0.74, good; ICC 〉 0.74, excellent. Results: Fifty-six ankles were included in the study, including 16 (57%) males and 12 (42%) females. Average anterior to posterior fibular sagittal translation was 0.89 ± 0.6 mm and posterior to anterior fibular sagittal translation was 0.49 ± 1.1 mm. Anterior to posterior translation means of exam 1 versus exam 2 showed no significant differences, means of 0.81 mm [0.7–0.9] versus 0.77 mm [0.7–1.0], and posterior to anterior means [95% CI] of 0.42 mm [0.3–0.5] versus 0.44 mm [0.2–0.6] (p-values 0.416 and 0.758, respectively). Excellent Inter- and intraobserver agreement was found for all measurements taken. Conclusion: Dynamic ultrasound allows one to effectively and readily evaluate sagittal translation of the distal tibiofibular joint. It is able to afford bilateral comparisons, which becomes critical as the amount of syndesmotic instability approaches greater degrees of subtlety

The Epidemiology of Navicular Injuries at the NFL Combine

Category: Sports Introduction/Purpose: Navicular injuries are documented to have the potential for significant impairment of foot function. Regardless of treatment choice, these injuries can result in persistent pain, advanced osteoarthritis, and chronic dysfunction. A clearer understanding of their prevalence in collegiate athletes as well as their impact on their NFL career would help team physicians better counsel players and their teams, and perhaps also aid in defining optimal treatment. The purpose of this study was to 1) determine the epidemiology of navicular fractures in players participating in the NFL combine, 2) define positions that might be at higher risk for sustaining this injury, and 3) evaluate the impact of navicular injuries on NFL draft position and NFL game play compared to matched controls. Methods: Data was collected from the NFL combine website on all participating players who had sustained a navicular injury before entering the NFL between 2009 and 2015. Medical records, imaging, and treatments were reviewed on all individuals who met these criteria. The epidemiology of navicular injuries was determined by evaluating the number of injuries, surgeries, games missed, position played and draft position of each player. Available exam and imaging findings were reviewed for each player. Players from 2009 to 2013 with a navicular injury were compared to matched controls. Control groups consisted of players who missed less than 2 games in college, played the same position, and did not have a previous surgery. NFL performance outcomes were evaluated through analysis of draft position, career length ≥2 years, and number of games played and games started within their first 2 years. All NFL performance data was obtained from STATS.com. Odds ratios were calculated using logistic regression to assess the risk of sustaining a navicular injury by position. Two-sample, two-tailed T-tests were computed to assess games missed in college and draft position in players with a navicular injury and NFL career consisting of games played, and started in the NFL in the first 2 years of their career versus control players. Results: A total of 2285 foot players participated in the NFL combine between 2009 – 2015. There were 15 navicular injuries (14 players) with an incidence of 0.6% of NFL football players participating in the combine during this time frame. Defensive backs had a statistically significant increased odds ratio (Odds ratio = 3.0, p=0.03) of sustaining a navicular injury, however only 3 defensive backs had a navicular injury. Three players had nonunions or a refracture and 2 players required a revision surgery. Fifty-seven percent of players with navicular injuries (72.7% of fractures) were undrafted versus 30.9% in the control group (P< 0.001). Twenty-nine percent of players with navicular fractures played 2 years in the NFL compared to 69.6% in the control group (P< 0.01). Conclusion: While only a small percentage of players at the NFL combine had a navicular injury, there was a significant increase in percentage of players undrafted and a decreased percent of players who played two years in the NFL when compared to controls. This demonstrates the detrimental effect this injury may have to a player’s career