Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ANKLE”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

Effect of ankle taping and bracing on vertical ground reaction forces during drop landings before and after treadmill jogging.

STUDY DESIGN: Single-group repeated-measures experimental design. OBJECTIVES: The purpose of this study was to evaluate the effects of prophylactic ankle stabilization on vertical ground reaction forces before and after treadmill jogging. BACKGROUND: Previous research has demonstrated acute effects of ankle taping and bracing on ankle joint kinematics and vertical ground reaction forces during drop landings. Based on the number of investigations demonstrating increased range of motion of the braced or taped ankle following exercise, it may be plausible that the aforementioned landing alterations may return to normal following an exercise bout. METHODS AND MEASURES: Fourteen healthy recreational participants performed stiff and soft drop landings before and after a 20-minute treadmill exercise bout under 3 different ankle stabilizer conditions (no stabilizer, ankle brace, and ankle tape). A forceplate was used to collect ground reaction force data under the dominant foot. The first and second peak impact force, as well as the time to each of the 2 peak forces, were determined for each trial and used as dependent variables. RESULTS: The time to reach peak forces were significantly less under the ankle brace and tape conditions in comparison to the control (no-stabilizer) condition. CONCLUSIONS: It appears that ankle taping and bracing decrease the time to reach peak impact forces. These alterations indicate that during dynamic activity the musculoskeletal structures of the body may be subjected to loads within shorter time periods. Whether these effects are detrimental over time remains speculative at this point and requires further research.

Adaptation, Physiological↗

Total ankle arthroplasty: indications, results, and biomechanical rationale.

Total ankle replacement was developed in the 1970s after the success of total hip and knee arthroplasty. The goal of total ankle arthroplasty is to decrease pain and improve function in the lower limb. Ideally, to be superior to an arthrodesis, the ankle replacement should provide the patient with good patterns of joint motion and the ability to walk and run and should have low complication rates. Unfortunately, total ankle arthroplasty has not been as successful as replacement of other joints. Published studies of early series with greater follow-up show that ankle arthroplasties did not provide lasting pain relief or improve function, and most ultimately failed. During the 1980s, many authors concluded that a total ankle arthroplasty was not warranted because of the generally poor long-term results and the high rate of complications. However, newer second-generation design techniques, innovative operative procedures, and dissatisfaction with the results of ankle arthrodesis have renewed interest in total ankle arthroplasties. This review describes the numerous types of ankle joint replacements, critically reviews the results, and reports on newer prostheses that incorporate more anatomic designs.

Ankle Joint↗

Effect of ankle position fixation on peak torque and electromyographic activity of the knee flexors and extensors.

The purpose of this study was to examine the effect of ankle position fixation on peak torque (PT) and electromyographic (EMG) activity of knee-joint muscles during isokinetic testing. Twelve female athletes performed isokinetic knee flexion and extension at 60 degrees and 180 degrees/s under two conditions: with the ankle fixed in a position of plantarflexion and with the ankle fixed in a position of dorsiflexion. Bipolar surface electrodes were placed on the vastus lateralis, vastus medialis, biceps femoris, medial hamstrings, and the lateral head of the gastrocnemius for determination of the root mean square of the EMG (rmsEMG) and the median frequency of the EMG (mfEMG). No significant differences in knee extensor PT were noted in either ankle position for each velocity tested. Significant differences were noted, however, in knee flexor PT (p < 0.05) at both 60 degrees and 180 degrees/s, with the greatest PT observed with the ankle fixed in dorsiflexion. Neither quadriceps, hamstrings, nor gastrocnemius rmsEMG activity was affected by ankle position; however, there was a significant difference in mfEMG for the gastrocnemius, with higher frequencies observed with the ankle fixed in plantarflexion (p < 0.01). These results suggest that ankle position effects knee flexor PT during open chain isokinetic movements. The reason for decreased knee flexor PT with the ankle fixed in plantarflexion is probably due to the gastrocnemius muscle being in a too shortened position, thereby preventing it from effectively producing force at the knee joint.

Adult↗

Comparison of diagnostic decision rules and structured data collection in assessment of acute ankle injury.

BACKGROUND: Ankle decision rules help to determine which patients with ankle injuries should undergo radiography. However, these rules are limited by imperfect generalizability and sensitivity. The judgement of physicians, aided by structured data collection, is a potential alternative. We compared the diagnostic performance of 2 decision rules with the performance of physicians, aided by structured data collection, in ruling out fracture in patients with acute ankle injury. METHODS: Consecutive patients with acute ankle injury who visited the emergency department of a teaching community hospital in Amsterdam were included in the study. After taking the patient's history and performing a physical examination, the surgical resident in each case completed a specially developed structured data form incorporating all of the variables in the Ottawa and Leiden ankle rules, as well as some additional variables. The form then asked whether the resident thought radiography was necessary. Each patient then underwent ankle and midfoot radiography. The films were independently interpreted by a radiologist and a trauma surgeon, who were both blinded to the information on the data form. Sensitivity, specificity and the percentage of patients for whom radiography was recommended were the main outcome measures. RESULTS: Of 690 consecutive patients, 647 met the inclusion criteria. Fractures were observed in 74 (11%) of these patients. Sensitivity was 89% (95% confidence interval [CI] 80% to 95%) for the Ottawa ankle rules, 80% (95% CI 69% to 88%) for the Leiden ankle rule and 82% (95% CI 72% to 90%) for physicians' judgement. Specificity was 26% (95% CI 23% to 30%), 59% (95% CI 55% to 63%) and 68% (95% CI 64% to 71%) respectively. Radiography was recommended in 76% (95% CI 72% to 79%), 46% (95% CI 42% to 50%) and 38% (95% CI 34% to 42%) of cases respectively. The Ottawa rules missed 8 fractures, of which 1 was clinically significant, the Leiden rule missed 15 fractures, of which 5 were clinically significant, and the residents missed 13 fractures, of which 1 was clinically significant. INTERPRETATION: Physicians' judgement, aided by structured data collection, was similar to existing international and local decision rules in terms of sensitivity in identifying cases requiring radiography and may outperform these prediction rules in terms of minimizing radiographic examinations for patients with ankle trauma.

Acute Disease↗

[The correlation between toe- and ankle pressure, clinical symptoms and angiography in patients with leg ischemia].

OBJECTIVE: The severity of leg ischemia is usually evaluated by measuring ankle pressure. This is a simple measurement but can be misleading in patients with severe sclerosis in ankle arteries in which case toe pressure is believed to be more reliable. The purpose of this study was to compare toe pressure with ankle pressure, clinical symptoms and angiography and thus evaluate the usefulness of toe pressure in the assessment of leg ischemia. MATERIAL AND METHODS: In total of 58 legs from 30 patients that came to Landspítali University Hospital because of leg ischemia we measured toe- and ankle pressure and assessed the clinical stage of leg ischemia. All patients also had an angiography of their leg arteries. RESULTS: There was a correlation between pressure measurements and the clinical stage of leg ischemia and also between pressure measurements and results from angiography of leg arteries. There was not a significant difference between the correlation for toe- and ankle pressure respectively. In two cases it was impossible to measure ankle pressure but in both cases it was possible to measure toe pressure. CONCLUSIONS: Toe- and ankle pressure measurements are equally useful in the evaluation of leg ischemia. Ankle pressure is a more simple measurement than toe pressure but can be impossible to perform when the ankle arteries are very sclerotic. When that is the case toe pressure can often be measured instead.

Aged↗

Acute ankle sprain: an update.

Acute ankle injury, a common musculoskeletal injury, can cause ankle sprains. Some evidence suggests that previous injuries or limited joint flexibility may contribute to ankle sprains. The initial assessment of an acute ankle injury should include questions about the timing and mechanism of the injury. The Ottawa Ankle and Foot Rules provide clinical guidelines for excluding a fracture in adults and children and determining if radiography is indicated at the time of injury. Reexamination three to five days after injury, when pain and swelling have improved, may help with the diagnosis. Therapy for ankle sprains focuses on controlling pain and swelling. PRICE (Protection, Rest, Ice, Compression, and Elevation) is a well-established protocol for the treatment of ankle injury. There is some evidence that applying ice and using nonsteroidal antiinflammatory drugs improves healing and speeds recovery. Functional rehabilitation (e.g., motion restoration and strengthening exercises) is preferred over immobilization. Superiority of surgical repair versus functional rehabilitation for severe lateral ligament rupture is controversial. Treatment using semirigid supports is superior to using elastic bandages. Support devices provide some protection against future ankle sprains, particularly in persons with a history of recurrent sprains. Ankle disk or proprioceptive neuromuscular facilitation exercise regimens also may be helpful, although the literature supporting this is limited.

Ankle Injuries↗

TEMPER: an acronym for ankle sprain rehabilitation.

As has been previously discussed, the incidence and resultant associated disabilities of ankle sprains have been well documented in the literature. The staggering statistics on long-term disability show that there is no such thing as a simple ankle sprain. The degree of disability is related to the extent of the initial injury as well as the follow-up medical care provided. It is this fact that requires a complete understanding of the injury as well as a proper treatment and rehabilitation program. One of the reasons cited for the long-term disability or lack of consistently good results in treating ankle sprains is the lack of uniformity in treatment. One possible reason is the lack of agreement in diagnostic techniques as well as the end diagnosis of a particular grade of ankle sprain. If a sprain is managed correctly, resultant disability will be kept to a minimum. A proper rehabilitation program may be the most important factor in preventing chronic instability. The acronym RICE falls short of complete ankle management. RICE primarily addresses the ankle edema. Thus, the patient's ankle is only partially rehabilitated. A rational approach to the management of ankle sprains is given. Upon reviewing a complete protocol for ankle sprain rehabilitation, the acronym TEMPER can be used judiciously to remember the key steps in the treatment plan. Through the use of this acronym, one can institute a complete rehabilitation program.

Ankle Injuries↗

Results of Watson-Jones ankle reconstruction for instability. The influence of articular damage.

We reviewed 32 ankles in 30 patients at an average of five years after a Watson-Jones tenodesis. All but one patient had had ankle pain before operation and 19 had had clicking, catching, or locking of the ankle. Eleven of these had an ankle arthrotomy at the time of ligament reconstruction for intraarticular pathology. At review seven of 23 ankles had a significant decrease in ankle motion, and five in subtalar motion, but only two were unstable on examination. Twenty-one ankles, however, caused some pain on activity and nine were tender on palpation. These findings indicate intra-articular degeneration or injury rather than simple instability. Radiographs of 16 ankles showed good varus and anterior-drawer stability. Seven had talocrural osteoarthritis, but only four showed grade-1 subtalar osteoarthritis. We found no correlation between follow-up time and long-term results. The Watson-Jones tenodesis provides good rotational and lateral ankle instability and does not appear to lead to subtalar degeneration.

Adolescent↗

Muscle, reflex and central components in the control of the ankle joint in healthy and spastic man.

In understanding the control of the ankle joint during different motor tasks, we have to investigate at least three components, namely the influence of i) the passive and intrinsic properties of the intact and active muscle system around the joint (termed the non-reflex component), ii) the mechanical importance of the stretch reflex in the stretched and unloaded muscles, and iii) the supraspinal control of the stretch reflex. This thesis is dealing with the importance of the three components in healthy and spastic persons during sitting, standing, and walking. The results are based on stretch reflex and H-reflex measurements from the ankle extensor muscles. During stretch reflex experiments the foot was mounted to a platform (portable during walking) from which the ankle joint torque and the position were measured. To elicit a stretch reflex, the ankle joint was rotated by a strong motor connected to the platform. The mechanical importance of the stretch reflex was investigated by measuring the changes in joint torque. Electrically, the stretch reflex was recorded as the compound muscle action potential through bipolar surface EMG electrodes placed over the soleus muscle. During H-reflex experiments, the tibial nerve was stimulated at the popliteal fossa and the H-reflex recorded over the soleus muscle as during stretch reflex experiments. To investigate how the contractile properties of a muscle in humans depend on the history of activation, we investigated the intrinsic stiffness of the ankle extensors in healthy subjects. At matched background contraction in sitting subjects, a prolonged contraction increased the intrinsic muscle stiffness by 49%. Muscle yielding has been considered especially important for understanding the reflex compensation. We found a general lack of muscle yield and a mechanically important non-reflex stiffness of the ankle extensors showing that non-reflex stiffness is a prominent factor in normal movements of the ankle joint. In both healthy and spastic persons, we found a mechanically strong stretch reflex in the isometric, contracted muscles during sitting. This posed the question; how is the reflex regulated during more functional motor tasks. This was dealt with by studying the H-reflex during isometric ramp contractions and during walking in healthy and spastic persons. In the healthy subjects the H-reflex was modulated in consistency with a task dependent control. In the spastic patients the H-reflex lacked a task dependent modulation. In consistency with earlier findings it was suggested that the decreased modulation could have been caused by decreased control of the pre-synaptic inhibition of the Ia terminals or a change in recruitment gain. To test if the stretch reflex behaved as the H-reflex, the short latency stretch reflex was investigated during walking. Here we found that the stretch reflex was strongly modulated during a step in healthy subjects as seen for the H-reflex, but when comparing the stretch reflex at matched excitation levels (same background EMGs) during standing and walking, no task-specific reflex modulation was found except the one relating to the excitation level. Therefore, the results emphasise that at least during walking and standing it is not always possible to draw conclusions about the stretch reflex based on observations of the H-reflex. When investigating the modulation of the short latency stretch reflex during walking in spastic patients, we found that the stretch reflex modulation was impaired in spastic patients at least to the extent demonstrated earlier for the H-reflex. The passive stiffness of the ankle joint was at the same time increased in the patients. At matched ankle extensor contraction levels, stretch responses were compared before and after reversible block of the common peroneal nerve and during an attempted, voluntary, fictive dorsiflexion after common peroneal nerve block. (ABSTRACT TRUNCATED)

Afferent Pathways↗

Restriction of foot supination by ankle braces in sudden fall situations.

OBJECTIVE: To investigate the restriction of foot supination in different shoe orthotic combinations for unexpected ankle turns. DESIGN: A supination platform was used to experimentally induce sudden ankle turns. BACKGROUND: This study expanded on previous investigations of the effectiveness of different ankle braces and the influence of shoe material on foot supination. METHODS: For 21 male subjects pressure distribution data, achilles tendon angle, and supination velocity were collected. A comparison between a shoe with cut upper material and an intact shoe was done to show the influence of upper material on supination. The effectiveness of four different orthotics inside of an intact shoe were tested in comparison to the same shoe without ankle brace. Additionally, subjects rated their perceived supination movement of the foot. RESULTS: Between experimental conditions no large differences for the pressure distribution patterns were found. Three of the ankle braces reduced foot supination as well as supination velocities. More than two times lower supination values were measured for a footwear condition in which the upper material was cut away. Already during the free-fall most ankle braces caused a substantial reduction of foot inversion. CONCLUSION: The experiments demonstrated the influence of the upper material of a shoe and different orthotics on foot supination. Biomechanical measurements are necessary because of limited capabilities of subjects in detecting subtalar angular motions. RELEVANCE: This study investigated the effectiveness of different shoe conditions and ankle braces under experimental conditions that simulated unexpected ankle turns, the most frequent causes of sport injuries. The results of the study provide insights into which factors influence the amount of foot supination during unexpected ankle turns.

Journal Article↗

The effects of powered ankle-foot orthoses on joint kinematics and muscle activation during walking in individuals with incomplete spinal cord injury.

BACKGROUND: Powered lower limb orthoses could reduce therapist labor during gait rehabilitation after neurological injury. However, it is not clear how patients respond to powered assistance during stepping. Patients might allow the orthoses to drive the movement pattern and reduce their muscle activation. The goal of this study was to test the effects of robotic assistance in subjects with incomplete spinal cord injury using pneumatically powered ankle-foot orthoses. METHODS: Five individuals with chronic incomplete spinal cord injury (ASIA C-D) participated in the study. Each subject was fitted with bilateral ankle-foot orthoses equipped with artificial pneumatic muscles to power ankle plantar flexion. Subjects walked on a treadmill with partial bodyweight support at four speeds (0.36, 0.54, 0.72 and 0.89 m/s) under three conditions: without wearing orthoses, wearing orthoses unpowered (passively), and wearing orthoses activated under pushbutton control by a physical therapist. Subjects also attempted a fourth condition wearing orthoses activated under pushbutton control by them. We measured joint angles, electromyography, and orthoses torque assistance. RESULTS: A therapist quickly learned to activate the artificial pneumatic muscles using the pushbuttons with the appropriate amplitude and timing. The powered orthoses provided approximately 50% of peak ankle torque. Ankle angle at stance push-off increased when subjects walked with powered orthoses versus when they walked with passive-orthoses (ANOVA, p < 0.05). Ankle muscle activation amplitudes were similar for powered and passive-orthoses conditions except for the soleus (approximately 13% lower for powered condition; p < 0.05). Two of the five subjects were able to control the orthoses themselves using the pushbuttons. The other three subjects found it too difficult to coordinate pushbutton timing. Orthoses assistance and maximum ankle angle at push-off were smaller when the subject controlled the orthoses compared to when the therapist-controlled the orthoses (p < 0.05). Muscle activation amplitudes were similar between the two powered conditions except for tibialis anterior (approximately 31% lower for therapist-controlled; p < 0.05). CONCLUSION: Mechanical assistance from powered ankle-foot orthoses improved ankle push-off kinematics without substantially reducing muscle activation during walking in subjects with incomplete spinal cord injury. These results suggest that robotic plantar flexion assistance could be used during gait rehabilitation without promoting patient passivity.

Journal Article↗

Factors Contributing to Chronic Ankle Instability: Kinesthesia and Joint Position Sense.

OBJECTIVE: To present a comprehensive review of the influence of altered kinesthesia and joint position sense on chronic ankle instability and to present a model connecting deficits in ankle position sense with the increased risk of sustaining lateral ankle sprains. DATA SOURCES: I searched MEDLINE for the years 1966-2001 using the key words ankle and kinesthesia or position sense and books on proprioception. DATA SYNTHESIS: Study findings suggest a risk for unprovoked lateral ankle sprains when the lateral border of the foot accidentally catches the ground surface during the late swing phase of normal locomotion. In normal situations, the lateral border of the foot clears the ground by only 5 mm, and a small increase in ankle-position error may substantially increase the risk of a collision. Findings of affected kinesthesia and joint position sense in subjects with chronically unstable ankles dominate over studies showing nonsignificant results, but the answer is far from clear. CONCLUSIONS/RECOMMENDATIONS: Changes in joint position sense and kinesthesia of a magnitude found in subjects with chronically unstable ankles can lead to an increased risk of sustaining lateral ankle sprains. Results from a small number of studies suggest that balance and coordination training can restore the increased uncertainty of joint positioning to normal levels.

Journal Article↗

The effect of molded and unmolded orthotics on balance and pain while jogging following inversion ankle sprain.

During this study, we examined the effects of using molded orthotics on persons who had suffered an inversion ankle sprain. We assessed standing balance with a digital balance evaluator for a group of 15 subjects who had no history of ankle sprains and for a group of nine subjects with acute ankle sprains. Then, we assessed the subjective pain experienced by ten subjects with acute ankle sprains while they jogged. During each part of the study, we tested the subjects while they were using a molded orthotic, an unmolded orthotic, and no orthotic in their shoes. We alternated the order of these treatments with each consecutive subject. The results indicate that subjects with a history of recent inversion ankle sprains had poorer balance than uninjured subjects. Molded orthotics had no effect on balance scores in the uninjured group, but their use improved balance scores in the ankle sprain group. Unmolded orthotics did not improve balance scores. Molded orthotics helped to decrease ankle pain during jogging for those with an ankle sprain, but unmolded orthotics did not. These findings suggest that molded orthotics may play a role in the treatment of inversion ankle sprains.

Journal Article↗

Ankle ranges of motion during extended activity periods while taped and braced.

Tape has traditionally been used to support the ankle during activity. More recently, commercial ankle braces have been worn as an alternative. The cumulative information on the effects of taped versus braced ankle support or interbrace comparisons is inconclusive. With few exceptions, ankle brace studies have collected data soon after support conditions were administered. Plantar-dorsiflexion and inversion-eversion ranges of motion (ROM) of 30 subjects were compared under conditions of unsupported, nonelastic adhesivetaped, and Swede-O and Sub Talar Support-braced ankles. We recorded measurements before activity and after periods of 15, 30, 45, and 60 minutes of selected activity on a motorized treadmill. All support conditions significantly reduced preactivity ROM in all directions compared to unsupported ankles. Results showed that the ankle significantly increased in plantarflexion ROM 15 minutes after the initiation of activity with tape or the SubTalar Support-brace, and after 30 minutes with the Swede-O brace. Tape showed further significant increases in plantarflexion ROM after 15-minute intervals of 30, 45, and 60 minutes of activity. All three support conditions had increased significantly in inversion ROM by 15 minutes of activity. The SubTalar Support brace showed a further significant inversion ROM increase between 15 and 30 minutes postactivity. We conclude that the Swede-O and SubTalar Support braces and tape offer significant preactivity ankle support in all four directions of movement. We also conclude that both braces offer longer postactivity support than tape. In inversion ROM and plantarflexion ROM, actions prevalent in ankle sprains, the Swede-O brace retained support longer than the SubTalar Support brace.

Journal Article↗

Changes in ankle joint proprioception resulting from strips of athletic tape applied over the skin.

OBJECTIVE: In part, the believed effectiveness of taping in preventing injuries may be in the increased proprioception that it provides through stimulation of cutaneous mechanoreceptors. The objective of this study was to examine the effectiveness of strips of athletic tape applied over the skin of the ankle in improving ankle joint movement and position perception. DESIGN AND SETTING: The study consisted of a single-group, repeated-measures design, where all subjects were tested under all conditions presented in a fully randomized order. Testing was performed in the biomechanics laboratory at Marquette University. SUBJECTS: Twenty healthy males (mean age = 20.3 +/- 1.5 yr) participated in this study. MEASUREMENTS: Ankle joint movement and position perception for plantar flexion and dorsiflexion were tested using a specially designed apparatus. Each individual was tested with and without two 12.7-cm (5-inch) strips of tape applied in a distal-proximal direction directly to the skin in front of and behind the subject's talocrural joint. RESULTS: Data were analyzed with repeated-measures analyses of variance (ANOVA) models. Our results indicate that under the nonweightbearing condition, taping significantly improved (p < .05) the ability of the subjects to perceive ankle joint position, especially for a 10 degrees plantar-flexed position. In the weightbearing condition, the use of tape did not significantly alter (p > .05) the ability of the subjects to perceive ankle position. Similarly, taping did not alter ankle movement perception in either the weightbearing or nonweightbearing condition (p > .05). CONCLUSIONS: We concluded that increased cutaneous sensory feedback provided by strips of athletic tape applied across the ankle joint of healthy individuals can help improve ankle joint position perception in nonweightbearing, especially for a midrange plantar-flexed ankle position.

Journal Article↗

Long-term ankle brace use does not affect peroneus longus muscle latency during sudden inversion in normal subjects.

OBJECTIVE: External ankle supports are widely used in sports medicine. However, ankle bracing in a healthy ankle over a sustained period has been scrutinized due to possible neuromuscular adaptations resulting in diminished dynamic support offered by the peroneus longus muscle. Although this claim is anecdotal in nature, we sought to investigate the effects of long-term ankle bracing using 2 commonly available appliances on peroneus longus latency in normal subjects. Our second purpose was to evaluate the effects of ankle bracing on peroneus longus latency before a period of extended use. DESIGN AND SETTING: A 3 x 3 x 2 design with repeated measures on the first and third factors was used in this study. All data were collected in the Sports Injury Research Laboratory. SUBJECTS: Twenty (12 men and 8 women) physically active college students (age = 23.6 +/- 1.7 years; height = 168.7 +/- 8.4 cm; weight = 69.9 +/- 12.0 kg) free of ankle or lower extremity injury in the 12 months before the study and not involved in a strength-training or conditioning program in the 6 months before the study. MEASUREMENTS: We evaluated peroneus longus latency by studying the electromyogram of the muscle after sudden foot inversion. RESULTS: Application of a lace-up or semirigid brace did not affect peroneus longus latency. Additionally, 8 weeks of longterm ankle appliance use had no effect on peroneus longus latency. CONCLUSIONS: The duration of the peroneus longus stretch reflex (latency) is neither facilitated nor inhibited with extended use of an external ankle support. Proprioceptive input provided by the muscle spindles within the peroneus longus does not appear to be compromised with the long-term use of ankle braces.

Journal Article↗

High-signal T2 changes of the bone marrow of the foot and ankle in children: red marrow or traumatic changes?

BACKGROUND: High-signal T2-weighted bone marrow changes can be found in both bone marrow edema and hematopoietic marrow and are often seen on pediatric MR images of the feet and ankle. OBJECTIVE: To evaluate whether high-signal T2 changes of the bone marrow seen on pediatric MRI of feet and ankles represent residual hematopoietic marrow. MATERIALS AND METHODS: A total of 402 bones in 41 pediatric MRI studies of feet and ankles (34 children, 1-18 years) were reviewed by two observers who were blinded to the patients' ages. The studies were reviewed for the presence of high-signal changes of the bone marrow on sagittal fluid-sensitive images. The frequency and location of these foci were correlated with the patients' ages. RESULTS: High-signal T2 changes of the bone marrow were seen in 45/402 bones (11%) and in 24/41 patients younger than 16 years (59%). The changes were most commonly located in the calcaneus (54%), followed by the talus (35%) and navicular bone (35%), invariably at the endosteal surface. In 16 ankles, such foci were seen in the feet but not in the distal tibia/fibula. Symmetric presence (two ankles) or absence (four ankles) of high-signal marrow were seen in six of seven patients with bilateral ankles. CONCLUSION: High-signal T2 changes of the bone marrow in pediatric feet and ankle MRIs have a symmetric, fairly consistent pattern and disappear after the age of 15 years. We believe that these high-signal areas are normal and represent residual hematopoietic marrow.

Adolescent↗

Magnetic resonance imaging findings in anterolateral impingement of the ankle.

OBJECTIVE: To demonstrate the MR imaging findings of anterolateral impingement (ALI) of the ankle. DESIGN AND PATIENTS: Nine patients with a history of ankle inversion injury and chronic lateral ankle pain were imaged with MR imaging, and the findings correlated with the results of arthroscopy. Three additional patients with clinically suspected ALI of the ankle were also included. Ankle MR imaging studies from 20 control patients in whom ALI was not suspected clinically were examined for similar findings to the patient group. RESULTS: MR imaging findings in the patients with ALI included a soft tissue signal mass in the anterolateral gutter of the ankle in 12 of 12 (100%) cases, corresponding to the synovial hypertrophy and soft tissue mass found at arthroscopy in the nine patients who underwent arthroscopy. Disruption, attenuation, or marked thickening of the anterior talofibular ligament was seen in all cases. Additional findings included signs of synovial hypertrophy elsewhere in the tibiotalar joint in seven of 12 patients (58%) and bony and cartilaginous injuries to the tibiotalar joint in five of 12 (42%). None of the control patients demonstrated MR imaging evidence of a soft tissue mass in the anterolateral gutter. CONCLUSIONS: ALI of the ankle is a common cause for chronic lateral ankle pain. It has been well described in the orthopedic literature but its imaging findings have not been clearly elucidated. The MR imaging findings, along with the appropriate clinical history, can be used to direct arthroscopic examination and subsequent debridement.

Adolescent↗