Patrick Shu-Hang Yung

A Systematic Review on Ankle Injury and Ankle Sprain in Sports

AbstractThis article systematically reviews epidemiological studies on sports injury from 1977 to 2005 in which ankle injury was included. A total of 227 studies reporting injury pattern in 70 sports from 38 countries were included. A total of 201 600 patients were included, with 32 509 ankle injuries. Ankle injury information was available from 14 098 patients, with 11 847 ankle sprains. Results show that the ankle was the most common injured body site in 24 of 70 included sports, especially in aeroball, wall climbing, indoor volleyball, mountaineering, netball and field events in track and field. Ankle sprain was the major ankle injury in 33 of 43 sports, especially in Australian football, field hockey, handball, orienteering, scooter and squash. In sports injuries throughout the countries studied, the ankle was the second most common injured body site after the knee, and ankle sprain was the most common type of ankle injury. The incidence of ankle injury and ankle sprain was high in court games and team sports, such as rugby, soccer, volleyball, handball and basketball. This systematic review provides a summary of the epidemiology of ankle injury in sports.

Understanding acute ankle ligamentous sprain injury in sports

This paper summarizes the current understanding on acute ankle sprain injury, which is the most common acute sport trauma, accounting for about 14% of all sport-related injuries. Among, 80% are ligamentous sprains caused by explosive inversion or supination. The injury motion often happens at the subtalar joint and tears the anterior talofibular ligament (ATFL) which possesses the lowest ultimate load among the lateral ligaments at the ankle. For extrinsic risk factors to ankle sprain injury, prescribing orthosis decreases the risk while increased exercise intensity in soccer raises the risk. For intrinsic factors, a foot size with increased width, an increased ankle eversion to inversion strength, plantarflexion strength and ratio between dorsiflexion and plantarflexion strength, and limb dominance could increase the ankle sprain injury risk. Players with a previous sprain history, players wearing shoes with air cells, players who do not stretch before exercising, players with inferior single leg balance, and overweight players are 4.9, 4.3, 2.6, 2.4 and 3.9 times more likely to sustain an ankle sprain injury. The aetiology of most ankle sprain injuries is incorrect foot positioning at landing – a medially-deviated vertical ground reaction force causes an explosive supination or inversion moment at the subtalar joint in a short time (about 50 ms). Another aetiology is the delayed reaction time of the peroneal muscles at the lateral aspect of the ankle (60–90 ms). The failure supination or inversion torque is about 41–45 Nm to cause ligamentous rupture in simulated spraining tests on cadaver. A previous case report revealed that the ankle joint reached 48 degrees inversion and 10 degrees internal rotation during an accidental grade I ankle ligamentous sprain injury during a dynamic cutting trial in laboratory. Diagnosis techniques and grading systems vary, but the management of ankle ligamentous sprain injury is mainly conservative. Immobilization should not be used as it results in joint stiffness, muscle atrophy and loss of proprioception. Traditional Chinese medicine such as herbs, massage and acupuncture were well applied in China in managing sports injuries, and was reported to be effective in relieving pain, reducing swelling and edema, and restoring normal ankle function. Finally, the best practice of sports medicine would be to prevent the injury. Different previous approaches, including designing prophylactice devices, introducing functional interventions, as well as change of games rules were highlighted. This paper allows the readers to catch up with the previous researches on ankle sprain injury, and facilitate the future research idea on sport-related ankle sprain injury.

Prevalence, Pattern, and Spectrum of Glenoid Bone Loss in Anterior Shoulder Dislocation: CT Analysis of 218 Patients

OBJECTIVE The purpose of our study was to determine the prevalence, pattern, and spectrum of glenoid bone loss in anterior shoulder dislocation, to relate this to the frequency of dislocation, and to test the appropriateness of the measurement method. SUBJECTS AND METHODS Two hundred eighteen patients with single or recurrent anterior shoulder dislocation underwent shoulder CT examination. Fifteen patients had bilateral dislocation. Prevalence and severity of glenoid bone loss and glenoid fracture were assessed. CT examinations of 56 control subjects without shoulder dislocation were evaluated for glenoid contour and side-to-side variation in glenoid width. RESULTS Glenoid bone loss was present in 27 (41%) of 66 patients with first-time unilateral dislocation and 118 (86%) of 137 patients with recurrent unilateral dislocation. Glenoid bone loss ranged from -0.3% to -33% (mean, -10.8% +/- 7.9%). Seventy-four (51%) of 145 patients had < or = 10% glenoid bone loss, 54 (37%) had between 10% and 20%, eight (6%) had between 20% and 25% glenoid bone loss, and nine (6%) had > or = 25% glenoid bone loss. Glenoid rim fractures were present in 49 (21%) of 233 dislocated shoulders. The number of dislocations correlated moderately with the severity of glenoid bone loss (r = 0.56). The normal side-to-side glenoid width variation was small (0.46 +/- 0.81 mm). CONCLUSION Glenoid bone loss is common in anterior shoulder dislocation. It is probably multifactorial in origin, is usually mild in degree, and has a maximum observed severity of -33%. Dislocation frequency cannot accurately predict the degree of bone loss.

Biomechanics of Supination Ankle Sprain A Case Report of an Accidental Injury Event in the Laboratory

Ankle sprain is the most common injury in sports, but the mechanism of injury is not clear. Injury mechanisms can be studied through many different approaches. Over the years, ankle kinematics has been studied during simulated subinjury or close-to-injury situations, that is, sudden simulated ankle spraining motion on inversion platforms. Because these tests did not induce real injury, they could only somewhat suggest the ankle kinematics during an ankle sprain injury. The most direct way is to investigate real injuries using biomechanical measuring techniques. However, it is obviously unethical to do experiments where test subjects are purposefully injured. Nevertheless, in rare cases, accidents may occur during biomechanical testing. It has been shown that video sequences from sports competitions can provide limited but valuable information for qualitative ankle injury analysis. However, quantitative biomechanics analysis of sport injury is not easy as it requires calibrated multiview video sequences. This study presented an accidental supination ankle sprain injury that occurred in a laboratory under a high-speed video and plantar pressure capturing setting.

First‐time shoulder dislocation: High prevalence of labral injury and age‐related differences revealed by MR arthrography

To evaluate abnormalities and age‐related differences after first‐time shoulder dislocation.

Kinematics Analysis of Ankle Inversion Ligamentous Sprain Injuries in Sports 2 Cases During the 2008 Beijing Olympics

Background:Ankle ligamentous sprain is common in sports. The most direct way to study the mechanism quantitatively is to study real injury cases; however, it is unethical and impractical to produce an injury in the laboratory. A recently developed, model-based image-matching motion analysis technique allows quantitative analysis of real injury incidents captured in televised events and gives important knowledge for the development of injury prevention protocols and equipment. To date, there have been only 4 reported cases, and there is a need to conduct more studies for a better understanding of the mechanism of ankle ligamentous sprain injury.Purpose:This study presents 5 cases in tennis and a comparison with 4 previous cases for a better understanding of the mechanism of ankle ligamentous sprain injury.Study Design:Case series; level of evidence, 4.Methods:Five sets of videos showing ankle sprain injuries in televised tennis competition with 2 camera views were collected. The videos were transformed, sy...

CT Compared with Arthroscopy in Quantifying Glenoid Bone Loss

OBJECTIVE This study investigated the accuracy of CT in determining the presence and severity of glenoid bone loss in patients with unilateral anterior shoulder dislocation. SUBJECTS AND METHODS Fifty patients (45 males, five females; mean age, 28.7 years; age range, 14-56 years) with anterior shoulder dislocation underwent shoulder CT examination before arthroscopy (mean time interval between CT and arthroscopy, 28.5 days; range, 9-73 days). Thirteen (26%) of the 50 patients had a single dislocation, whereas the remaining 37 patients (74%) had recurrent dislocation (mean, 8.2 dislocations; range, 2-50 dislocations). RESULTS Glenoid bone loss was evident in 41 (82%) of the 50 patients at arthroscopy. Compared with arthroscopy, CT had a sensitivity in detecting glenoid bone loss of 92.7%; specificity, 77.8%; positive predictive value, 95.0%; and negative predictive value, 70.0%. Three false-negative CT assessments had 5%, 10%, and 10% glenoid bone loss, respectively, at arthroscopy. Two false-positive CT assessments had 8.7% and 5.7% glenoid bone loss on CT, although no bone loss was apparent at arthroscopy. There was a strong correlation between CT and arthroscopy with respect to the severity of glenoid bone loss (r = 0.79, 95% CI = 0.659-0.877, p < 0.0001). CONCLUSION CT has both a high sensitivity and a high specificity for detecting glenoid bone loss, and agreement with arthroscopy regarding the severity of glenoid bone loss is good. CT can be used to assess glenoid bone loss and the need for bone augmentation surgery.

Sport-related ankle injuries attending an accident and emergency department

INTRODUCTION This study investigated the sport-related ankle injuries attending an accident and emergency (A&E) department during a 1-year period. METHODS A total of 1715 sports injuries cases attending an A&E department from 1 January 2005 to 31 December 2005 were prospectively recorded. Details of each classified case were recorded in a computerised record system by the triage nurse. At the end of the study period, all sport-related ankle injury cases were analysed. RESULTS A total of 240 sport-related ankle injury cases were reported. Most cases were sustained from basketball (32.9%), soccer (31.7%) and hiking (5.8%) sports. The majority of the cases was ligamentous sprains (81.3%) and fractures (10.4%). The mean age of all patients was 24.6 years (S.D. = 12.3). Four fifths (80.4%) were male patients. All cases were not life threatening. Most cases (99.2%) were referred to orthopedics specialty. Radiography was routinely employed in 99.2% of the cases. Ligamentous sprains were mostly sustained in basketball (37.4%) and soccer (28.7%), and were often treated with bandaging (60.0%) and analgesics (48.7%). Most cases were discharged with or without referral to physiotherapy and specialty clinic (95.4%). Fractures were mostly sustained in soccer (52.0%), basketball (20.0%) and hiking (16.0%), and were very often admitted to hospital wards (84.0%). The estimated A&E attendance rate for all sports injuries, ankle injuries, ligamentous sprains and fractures were 1.68, 0.24, 0.19 and 0.02/1000 person-year. CONCLUSIONS The results of this study together with the previous study on ankle sprain epidemiology suggested the following sports ankle injury pattern in Hong Kong-major and serious ankle ligamentous sprains and fractures were sustained from basketball, soccer and hiking, leading to A&E attendance, while minor sprains were sustained in running and jogging and racquet sports. We suggested that the Sports medicine specialists in Hong Kong should emphasise the ankle injury prevention strategies in these sports.

Estimating the complete ground reaction forces with pressure insoles in walking

This study presented a method to estimate the complete ground reaction forces from pressure insoles in walking. Five male subjects performed 10 walking trials in a laboratory. The complete ground reaction forces were collected during a right foot stride by a force plate at 1000Hz. Simultaneous plantar pressure data were collected at 100Hz by a pressure insole system with 99 sensors covering the whole plantar area. Stepwise linear regressions were performed to individually reconstruct the complete ground reaction forces in three directions from the 99 individual pressure data until redundancy among the predictors occurred. An additional linear regression was performed to reconstruct the vertical ground reaction force by the sum of the value of the 99 pressure sensors. Five other subjects performed the same walking test for validation. Estimated ground reaction forces in three directions were calculated with the developed regression models, and were compared with the real data recorded from force plate. Accuracy was represented by the correlation coefficient and the root mean square error. Results showed very good correlation in anterior-posterior (0.928) and vertical (0.989) directions, and reasonable correlation in medial-lateral direction (0.719). The root mean square error was about 12%, 5% and 28% of the peak recorded value. Future studies should aim to generalize the methods or to establish specific methods to other subjects, patients, motions, footwear and floor conditions. The method gives an extra option to study an estimation of the complete ground reaction forces in any environment without the constraints from the number and location of force plates.

Epidemiology of Injuries in Hong Kong Elite Badminton Athletes

This study retrospectively reviewed the injury epidemiology on 44 Hong Kong elite badminton players in 2003. Team training records were reviewed to retrieve the training and competition hours, while the medical records from the physiotherapy department were reviewed to obtain information regarding injuries. A total of 253 injuries (128 recurrent and 125 new injuries) were recorded, which accounted for an overall incidence rate of 5.04 per 1,000 player hours. Elite senior athletes had a higher incidence rate of recurrent injuries, while elite junior and potential athletes had a higher incidence rate of new injuries. A total of 1,219 visits (4.82 per athlete) to the physiotherapy department were recorded, which cost HK