Ground reaction forces and EMG activity with ankle bracing during inversion stress

PURPOSE: The purpose of this investigation was to evaluate the effects of external ankle support on ground reaction forces and myoelectrical activity of selected lower extremity muscles during dynamic inversion stress. METHODS: Twenty-four healthy males performed five trials of a lateral dynamic movement at a rate between 80-90% of their maximal speed under three ankle brace conditions (no brace--control, Aircast Sport-Stirrup, Active Ankle). Ground reaction forces along the mediolateral axis and EMG activity of the peroneus longus, tibialis anterior, and medial gastrocnemius were simultaneously recorded during force plate contact. RESULTS: Ankle bracing did not affect peak impact force (P > 0.05), maximum loading force (P > 0.05), or peak propulsion force (P > 0.05) in the lateral direction compared with the control condition. Ankle bracing reduced the EMG activity of the peroneus longus during peak impact force compared with the control condition (P < 0.05), although no differences were noted between the two braces. Furthermore, peroneous longus activity during maximum loading force and peak propulsion remained unaffected (P < 0.05). Ankle bracing did not affect the EMG activity of the tibialis anterior and medial gastrocnemius at the point of peak impact force, maximum loading force (P > 0.05), and peak propulsion force (P > 0.05). CONCLUSIONS: These data suggest that ankle bracing may not affect the forces experienced at the foot and ankle, but helps reduce the strain placed on the peroneus longus during peak impact force. Furthermore, ankle bracing does not alter the function of the tibialis anterior and medial gastrocnemius during dynamic inversion stress.     

Braced for impact: reducing military paratroopers' ankle sprains using outside-the-boot braces

BACKGROUND: Ankle injuries account for 30 to 60% of all parachuting injuries. This study was designed to determine if outside-the-boot ankle braces could reduce ankle sprains during Army paratrooper training. METHODS: The randomized trial involved 777 volunteers from the U.S. Army Airborne School, Fort Benning, Ga. Of this group, 745 completed all study requirements (369 brace-wearers and 376 non-brace-wearers). Each volunteer made five parachute jumps, for a total of 3,674 jumps. RESULTS: The incidence of inversion ankle sprains was 1.9% in non-brace-wearers and 0.3% in brace-wearers (risk ratio, 6.9; p = 0.04). Other injuries appeared unaffected by the brace. Overall, 5.3% of the non-brace group and 4.6% of the brace group experienced at least one injury. The risk ratio for injured individuals was 1.2:1 (non-brace to brace groups; p = 0.65). CONCLUSION: Inversion ankle sprains during parachute training can be significantly reduced by using an outside-the-boot ankle brace, with no increase in risk for other injuries.     

Does ice immersion influence ankle joint position sense?

The purpose of this study was to determine whether a fifteen minute ice immersion treatment influenced the normal ankle joint position sense at 40% and 80% range of inversion and to establish the length of treatment effect through monitoring the rewarming process. Forty nine healthy volunteers between the ages of 17 and 28 were tested. Subjects were screened to exclude those with a history of ankle injuries. The subject's skin temperature over antero-lateral aspect of the ankle was measured using a thermocouple device during the fifteen minutes ice intervention and thirty minutes post-intervention. Testing of ankle joint position sense using the pedal goniometer was performed before and after a clinical application of ice immersion. The testing required the subject to actively reposition their ankle at 40% and 80% of their total range of inversion. The majority of subjects experienced numbness of the foot and ankle by the fifth or sixth minute during ice immersion. One minute after immersion skin temperatures averaged 15 degrees C + 1.7 degrees C. Skin temperature was seen to rise relatively rapidly for the first ten minutes and then slowed considerably. Subjects had not returned to the pre-test skin temperatures by thirty minutes. A significant difference in ankle joint position sense (p < 0.0499) following fifteen minutes of ice immersion was found. However, the magnitude of this difference (0.5 degree) would not be deemed significant in clinical practice. The research found no significant difference in joint position sense between 40% and 80% of the range of inversion both before and after cryotherapy. These findings suggest that the clinical application of cryotherapy is not deleterious to joint position sense and assuming normal joint integrity patients may resume exercise without increased risk of injury.     

Concomitant injuries after upper ankle joint dislocations

Functional treatment with the Air Stirrup Ankle Brace recommended by C. N. Stover in 1979 can reduce pathological inversion of the ankle joint. In our retrospective study of 109 patients treated by this kind of ankle brace we found 96 patients (88%) with excellent results. Only 13 patients (12%) reported moderate to good results. To detect and characterize their painful conditions of ankles we did a clinical, radiological and MRI-Investigation. In only 2 cases we found a moderate instability after clinical investigation, anterior stress roentgenogram and talar tilt. By using the MRI-investigation 1.0 Tesla with a 512 x 360 Matrix we could find 10 cases with osteochondral lesions of the ankle. In 7 cases there was separated ossicle in the fibulotalar joint, in 1 case we detected a fracture of the processus anterior tali, in another case we could see a posttraumatic lesion of the talus and calcaneus with bone bruise and at least one osteochondral fracture of the distal tibia. The capability of the MRI to detect particularly osteo-chondral lesions of the talus and the tibiofibular joint was shown in 10 of 13 cases. Therefore we recommend to do an MRI-investigation on all patients after ankle sprain if there are painful conditions within the ankle after conservative treatment.     

The effects of functional knee braces on speed in collegiate basketball players

Knee braces are worn by many athletes following injury. The purpose of this study was to determine whether two functional knee braces (noncustom design) significantly affected straight line and successive turning trial running times in noninjured collegiate basketball players. Twenty-five coed basketball players completed 2 days of running trials. Subjects ran three full lengths of a basketball court and 10 lengths between the baseline and the foul line first without wearing a brace, then wearing either a DonJoy GoldPoint brace or an Omni OS-5 brace, and finally wearing the other brace. The results indicated no significant difference (p < .05) in straight line or successive turning running times when the two braces were compared with the nonbraced condition and when the two braces were compared with each other. The results implied that speed was not significantly affected by a functional knee brace in noninjured collegiate basketball players.     

A comparative study of TLSO, Charleston, and Milwaukee braces for idiopathic scoliosis

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To determine which of TLSO, Charleston, or Milwaukee bracing best prevents curve progression and surgery in adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Bracing has been shown to prevent curve progression in idiopathic scoliosis, when compared with no treatment. However, there is little literature available comparing the effectiveness of different brace designs. METHODS: One hundred seventy patients who completed brace treatment for adolescent idiopathic scoliosis between 1988 and 1995 were studied. Forty-five thoracolumbosacral orthoses, 95 Charleston braces, and 35 Milwaukee braces were used. Thoracolumbosacral orthoses and Charleston braces were used on comparable curves, whereas Milwaukee braces were used in a subgroup in which the other brace designs were considered inappropriate. Evaluated were the absolute increase in curve severity, the percentage of curves that progressed beyond 6 degrees and 10 degrees thresholds, and the percentage of patients who underwent surgery. RESULTS: Age, Risser stage, curve size, and time braced and observed did not differ among groups. Mean progression of the curve during bracing was 1.1 degrees with thoracolumbosacral orthosis, 6.5 degrees with the Charleston brace, and 6.3 degrees with the Milwaukee brace (P = 0.012; analysis of variance). Proportion of patients with more than 10 degrees of curve progression was 14% with thoracolumbosacral orthosis, 28% with the Charleston brace, and 43% with the Milwaukee brace (P = 0.017; chi-square). The proportion of patients who underwent surgery was 18% with thoracolumbosacral orthosis, 31% with the Charleston brace, and 23% with the Milwaukee brace (P = 0.26; chi-square). CONCLUSIONS: The thoracolumbosacral orthosis was superior at preventing curve progression in adolescent idiopathic scoliosis.     

The role of the pulmonary circulation in the regulation of coagulation and fibrinolysis in relation to major surgery

A total of 18 competitive and recreational athletes were enrolled in a randomized, prospective study looking at the effect of pneumatic leg braces on the time to return to full activity after a tibial stress fracture. All patients had positive bone scans and 15 had positive radiographic findings by Week 12. There were two treatment groups. The traditional treatment group was treated with rest and, after 3 pain-free days, a gradual return to activity. The pneumatic leg brace (Aircast) group had the brace applied to the affected leg and then followed the same return to activity guidelines. The guidelines consisted of a detailed functional progression that allowed pain-free return to play. The brace group was able to resume light activity in 7 days (median) and the traditional group began light activity in 21 days (median). The brace group returned to full, unrestricted activity in 21 +/- 2 days, and the traditional group required 77 +/- 7 days to resume full activity. The Aircast pneumatic brace is effective in allowing athletes with tibial stress fractures to return to full, unrestricted, pain-free activity significantly sooner than traditional treatment.     

Expression of HNF-1 alpha and HNF-1 beta in various histological differentiations of hepatocellular carcinoma

BACKGROUND: This study examined the effects of aerobic fitness and exercise history on self-reported affect during and after acute aerobic exercise and quite reading. METHODS: Active and sedentary participants (N = 41) reported their psychological affect during two separate conditions in a counterbalanced design: (1) exercise on a cycle ergometer at 50% predicted VO2 max, and (2) quiet reading in a reclining chair. Affect was assessed prior to, every 3 minutes during, and at 5 and 20 minutes after each 24-minute exercise and reading period. RESULTS: Analysis revealed that active participants were significantly more positive than the sedentary group during exercise and at 5 minutes postexercise. The groups were similar in affect at 20 minutes postexercise. No between-group differences were found during the reading condition. Exercise enhanced affect compared to reading only for the active group. In addition, the affective responses of both groups were influenced by pre-exercise affect, with the greatest increases observed for those reporting the lowest affect before activity. CONCLUSIONS: These results suggest that affective responses during and after aerobic exercise were influenced by exercise history and aerobic fitness, but moderated by pre-activity scores.     

Diagnostic ophthalmic cytopathology--past, present and future

OBJECTIVE: To assess whether accident and emergency (A&E) nurses using the Ottawa Ankle Rules could detect all ankle fractures. DESIGN: Prospective observational study. SETTING: A&E department of a university teaching hospital. SUBJECTS: All patients who presented with ankle injuries who were initially assessed by a nurse taught the Ottawa Ankle Rules. OUTCOME MEASURES: (1) The numbers of patients referred by the nurse for ankle radiography; (2) of these, the number with ankle fractures; (3) of those not sent for radiography initially by the nurse, the number who subsequently had x rays (ordered by the doctor) and had a fracture; (4) of those having no x rays, the number who reattended later. RESULTS: 324 patients were eligible; 238 had x rays at the request of the nurse (73%); 48 of these (20%) were diagnosed as having a fracture. Of those 86 patients not sent for radiography by the nurse, 19 subsequently had x ray examinations at the request of a doctor and no fracture was detected. Of the 67 not sent for radiography, none returned within the subsequent eight weeks. CONCLUSIONS: Nurses can apply the Ottawa Ankle Rules safely without missing acute fractures; that is, of those who were not sent for radiography by nurses, none subsequently reattended the A&E department or the trauma service of the Bristol Royal Infirmary during the following two months.     

Diaphragmatic paralysis

Ankle inversion injuries are the most common injury in sport and yet treatment is controversial. One result is chronic ankle instability, an injury for which criteria for surgical intervention are unclear. This prospective study of 14 patients showed that a large proportion of patients had no detectable abnormality on preoperative investigation, but were subsequently shown to have an abnormality under general anaesthesia. This suggests that a good history of chronic instability is more sensitive an indicator than conventional investigations. Stress views under anaesthesia may confirm the problem.     

Persistent disability associated with ankle sprains: a prospective examination of an athletic population

The purpose of this study was to examine a young athletic population to update the data regarding epidemiology and disability associated with ankle injuries. At the United States Military Academy, all cadets presenting with ankle injuries during a 2-month period were included in this prospective observational study. The initial evaluation included an extensive questionnaire, physical examination, and radiographs. Ankle sprain treatment included a supervised rehabilitation program. Subjects were reevaluated at 6 weeks and 6 months with subjective assessment, physical examination, and functional testing. The mean age for all subjects was 20 years (range, 17-24 years). There were 104 ankle injuries accounting for 23% of all injuries seen. There were 96 sprains, 7 fractures, and 1 contusion. Of the 96 sprains, 4 were predominately medial injuries, 76 were lateral, and 16 were syndesmosis sprains. Ninety-five percent had returned to sports activities by 6 weeks; however, 55% of these subjects reported loss of function or presence of intermittent pain, and 23% had a decrement of >20% in the lateral hop test when compared with the uninjured side. At 6 months, all subjects had returned to full activity; however, 40% reported residual symptoms and 2.5% had a decrement of >20% on the lateral hop test. Neither previous injury nor ligament laxity was predictive of chronic symptomatology. Furthermore, chronic dysfunction could not be predicted by the grade of sprain (grade I vs. II). The factor most predictive of residual symptoms was a syndesmosis sprain, regardless of grade. Syndesmosis sprains were most prevalent in collision sports. This study demonstrates that even though our knowledge and understanding of ankle sprains and rehabilitation of these injuries have progressed in the last 20 years, chronic ankle dysfunction continues to be a prevalent problem. The early return to sports occurs after almost every ankle sprain; however, dysfunction persists in 40% of patients for as long as 6 months after injury. Syndesmosis sprains are more common than previously thought, and this confirms that syndesmosis sprains are associated with prolonged disability.     

A comparative study of treadmill tests and heel raising exercise for peripheral arterial disease

OBJECTIVES: This two part study validated a 1 min treadmill exercise test and compared this with simple heel raising exercise. METHODS: In an initial study of 24 claudicants (aged 43-79, median 63 years), ankle pressures were measured immediately after repeated treadmill exercises: for 1 min, until onset of claudication, and until maximum tolerated walking distance. Absolute value, fall and percent change in pressures were calculated. The results of this part of the study were then used as a "gold standard" for comparison with 30 s of heel raising and treadmill exercise. This second stage was performed on 21 symptomatic limbs (14 claudicants aged 42-73, median 69 years). RESULTS: Variability was least for pressures expressed as percent change after 1 min of exercise. The paired t-test revealed a significant correlation between the two methods of exercise (p < 0.05). CONCLUSION: Heel raising produced changes in ankle pressure which correlated well with those induced by treadmill exercise. We recommend the use of simple heel raising when a stress test is required to diagnose lower limb arterial insufficiency in the outpatient clinic.     

Eosinophilic myopathic syndromes

The purpose of this study was to develop a standardised maximal treadmill exercise test performed until fatigue in order to find reproducible markers for anaerobic metabolism, specifically adenine nucleotide degradation. Six Standardbred trotters performed an incremental maximal treadmill exercise test in 1 min steps (starting with 7 m/s) until they could no longer keep pace with the treadmill. The test was performed twice with at least one week between the tests. Heart rate was recorded and venous blood samples were obtained during the test and in the recovery period for determination of plasma lactate, hypoxanthine, xanthine and uric acid. Muscle biopsy samples (m. gluteus) were collected at rest, immediately post exercise, and after 15 min recovery and analysed for their concentrations of glycogen, creatine phosphate (CP), adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), inosine monophosphate (IMP) and muscle lactate (MLa). Significant decreases in glycogen, CP and ATP and significant increases in IMP and MLa were seen immediately post exercise. None of these metabolites had returned to resting levels after 15 min of recovery. A marked increase in plasma lactate (PLa) occurred during exercise and the peak concentration (mean value = 27.2 mmol/l) was reached within 5 min of recovery. Plasma uric acid concentration did not increase during exercise but rose markedly immediately post exercise, reaching the highest level (mean value = 121.5 micromol/l) at 20-30 min recovery. The duration of the maximal test was related to peak PLa and the uric acid concentration at 30 min of recovery. A correlation was also found between the ATP and IMP concentrations immediately post exercise and the plasma uric acid concentration at 30 min of recovery. The results show that this treadmill test triggered anaerobic metabolism and also that uric acid concentration post exercise seems to be a marker for the adenine nucleotide degradation that occurs during intense exercise. No significant differences were seen in metabolic response between the 2 test occasions.     

Cardiorespiratory kinetics during exercise of different muscle groups and mass in old and young

The purpose was to compare cardiorespiratory kinetics during exercise of different muscle groups (double-leg cycling vs treadmill walking and single-leg ankle plantar flexion) in old and young subjects. Oxygen uptake (VO2) during exercise transitions was measured breath by breath, and the phase 2 portion of the response was fit by a monoexponential for determination of the time constant (tau) of VO2. Two separate studies were performed: in study 1, 12 old (age 66.7 yr) and 16 young (aged 26.3 yr) subjects were compared during cycling and ankle plantar flexion exercise, and in the study 2, five old (aged 69.6 yr) and five young (24.4 yr) subjects were compared during cycling and treadmill walking. VO2 transients during square-wave cycling exercise were significantly slower in the old compared with the young groups. In contrast, VO2 kinetics did not differ between old and young groups during plantar flexion exercise. Heart rate (HR) kinetics followed the same pattern, with tau HR being significantly slower in the old vs young groups during transitions to cycling but not to plantar flexion. In study 2 tau VO2 and tau HR during on-transients to treadmill square-wave exercise were significantly slower in the old group compared with the young group, but tau VO2 was significantly faster during treadmill exercise than during cycling in the old group. The differences with aging between the modes of exercise may be related to the muscle mass involved and the circulatory demands. On the other hand, slowed VO2 kinetics with age appear to occur in a mode (cycling) in which the muscles are not accustomed to the activity, whereas in a mode of normal activity (walking) and with the muscle groups (plantar flexors) accustomed to the activity, VO2 kinetics are not slowed to the same degree with age.     

The Milwaukee brace for the treatment of adolescent idiopathic scoliosis. A review of one thousand and twenty patients

We reviewed the medical records and roentgenograms of 1020 patients who had been managed for adolescent idiopathic scoliosis, between January 1954 and December 1979, with a Milwaukee brace; we wished to determine whether use of the brace had effectively altered the natural history of the disease. The findings were considered with respect to a previous study of 727 children who had had comparable curves and had not initially been managed with the brace but had been followed for progression of the curve, during the same time-span as that in the current study. Of those 727 patients, 558 (77 percent) had no progression of the curve. The average age of the 1020 patients at the time that treatment with the brace was begun was thirteen and one-half years (range, ten to seventeen years). None of the patients had received any other treatment, and all had been managed only by the physicians participating in this study. In both the current and the earlier series, the outcome was considered a failure if the curve had increased 5 degrees or more; in the patients in the current study, who were managed with the brace, the outcome was also considered a failure if operative intervention had been needed. Of the 1020 patients in the current series, 229 (22 percent) had operative intervention; this rate was higher in the patients who had a curve of more than 30 degrees at the time of bracing and in those who had a Risser sign of 0 or 1. The 791 remaining patients, who were managed with the brace only, had a mild improvement of 1 to 4 degrees at the time that use of the brace was discontinued (the difference being within the margin of error of measurement). With respect to curves of between 20 and 39 degrees, the rate of failure was lower in the current series of patients who had been managed with the brace than in the earlier series of patients who had not been thus managed but had been followed for progression. Progression of the curve was found to be related to the pattern and magnitude of the curve; the age of the patient at the time of presentation; the Risser sign; and, in girls, the menarchal status. We recommend that immature adolescents who have a curve of more than 25 degrees and a Risser sign of 0 be managed with a brace immediately, rather than after progression has been documented.     

The effect of flumazenil on CNS oxygen toxicity in the rat

The effect of afferent cutaneous electrical stimulation on the spasticity of leg muscles was studied in 20 patients with chronic hemiplegia after stroke. Stimulation electrodes were placed over the sural nerve of the affected limb. The standard method of cutaneous stimulation, TENS with impulse frequency of 100 Hz, was applied. The tonus of the leg muscles was measured by means of an electrohydraulic measuring brace. The EMG stretch reflex activity of the tibialis anterior and triceps surae muscles was detected by surface electrodes and recorded simultaneously with the measured biomechanical parameters. In 18 out of 20 patients, a mild but statistically significant decrease in resistive torques at all frequencies of passive ankle movements was recorded following 20 min of TENS application. The decrease in resistive torque was often (but not always) accompanied by a decrease in reflex EMG activity. This effect of TENS persisted up to 45 min after the end of TENS. The results of the study support the hypothesis that TENS applied to the sural nerve may induce short-term post-stimulation inhibitory effects on the abnormally enhanced stretch reflex activity in spasticity of cerebral origin.     

Complete neurological recovery following prolonged cardiac arrest. Description of a clinical case

The therapy of fibular ligament ruptures is still a controversial subject. Reports on healing processes following operative or conservative treatment have been verified hitherto by means of clinical examinations and stress tests. The MRT, as a highly sensitive non-invasive method, allows exact documentation of the ligament structures in the ankle joints. This technique was used in a randomized clinical trial over a 6-month period. The 29 patients (ages 17-51 years) had recent ligament rupture [admission criteria: clinical signs of trauma, talar tilt in anteroposterior stress radiographs (15 kp) > or = 10 degrees, talar shift > or = 10 mm] were examined with regard to ligament healing during functional therapy with AIRCAST pneumatic leg braces. Within the first week an MRT was done for verification of ligament injury. Treatment was conservative and functional: lower leg cast for 2 weeks and subsequent mobilization with protection provided by an AIRCAST brace. Follow-up examination was 3 months after injury, taking the form of clinical examination, a-p-radiographs with stress tests, and MRT. In all patients both clinical and radiological examination confirmed that ligament structures had healed, as was also verified by MRT.     

Response of the nose to exercise in healthy subjects and in patients with rhinitis and asthma

BACKGROUND: Although the nose and the bronchi are both involved in the process of regulating respiratory heat exchange, thermal changes may precipitate airway obstruction during exercise but rarely cause nasal obstruction in patients with rhinitis. The cause of the different response of the nose and bronchial tree has hardly been investigated. This study was performed to assess the response of the nose during exercise in the presence of rhinitis, asthma, and in normal controls. METHODS: Ten healthy subjects (group 1), 15 patients with asthma and rhinitis (group 2), 10 with rhinitis only (group 3), and 11 with asthma only (group 4) were included in the study. Exercise was performed on a bicycle ergometer for six minutes, reaching a heart rate of 80% of predicted. Bronchial and nasal responses were measured by forced expiratory volume in one second (FEV1) and posterior rhinomanometry, respectively. A drop in the FEV1 of 20% or more was considered a positive exercise induced asthma challenge test. RESULTS: Heart rate and ventilation increased by a similar proportion in the four groups. The FEV1 significantly decreased in asthmatic patients (groups 2 and 4) but it did not change in healthy subjects (group 1) or in those with rhinitis (group 3). Thirteen asthmatic patients developed exercise induced asthma. Nasal patency increased with exercise by a similar proportion in all groups, and no differences were detected between those with rhinitis (groups 2 and 3) and those without (groups 1 and 4). Nasal patency had returned to basal values at 25 minutes after completion of exercise in the four groups. The nose of patients with exercise induced asthma, however, remained significantly more patent than in patients without exercise induced asthma between 10 and 30 minutes after exercise. CONCLUSIONS: These results suggest that the nose responds differently from the bronchi during exercise induced airway obstruction: whereas the bronchial tree responds by becoming narrowed, the nose becomes more patent. These findings suggest that the mechanisms regulating the response of the nose to exercise are different from those involved in the response of the bronchial tree.     

Hepatic blood flow in horses during the recuperative period from maximal exercise

OBJECTIVE: To determine effects of walking or standing on hepatic blood flow of horses after brief, intense exercise. ANIMALS: 6 adult Thoroughbreds (4 mares, 2 geldings). PROCEDURE: Horses were preconditioned on a treadmill to establish uniform level of fitness. Once fit, treadmill speed causing each horse to exercise at 120% of maximal oxygen consumption was determined and used in simulated races at 14-day intervals. In a three-way crossover study, horses were exercised at a speed inducing 120% of maximal oxygen consumption until fatigued or for a maximum of 2 minutes. Three interventions were studied: resting on the treadmill (REST), exercised then standing on the treadmill for 30 minutes (MS), and exercised then walking at 2 m/s for 30 minutes (MW). At 60 seconds after completion of exercise, bromsulphalein (BSP) was infused IV, and blood samples were collected every 2 minutes for 30 minutes for analysis of BSP concentration. Hematocrit and plasma total solids concentration were measured. Pharmacokinetic parameters were derived, using nonlinear regression, and were compared, using Friedman's repeated measures analysis on ranks. RESULTS: Plasma BSP concentration was higher after exercise. Median hepatic blood flow (BSP clearance) decreased significantly from 23.8 (REST) to 20.7 (MS) and 18.7 (MW) ml/min/kg. Median steady-state volume of distribution of BSP decreased from 47.6 (REST) to 42.7 (MW) and 40.2 (MS) ml/kg. Differences among trials were not significant when horses walked or stood after exercise. CONCLUSIONS: Hepatic blood flow and pharmacokinetics of BSP are markedly altered immediately after exercise. Limiting movement of horses during this period did not affect hepatic blood flow.     

Arthroscopic treatment of soft-tissue impingement of the ankle in athletes

Sixty ankle arthroscopies were performed on patients with chronic soft-tissue impingement of the ankle after an ankle sprain between January 1989 and January 1994. Preoperative examination findings featured tenderness localized to the anterolateral aspect of the ankle, no instability, and, with the exception of 2 patients, normal radiographs. A preoperative bone scan was performed on 34 patients and was positive in each case but was not specific. Arthroscopy was performed an average of 23 months after injury. Results were determined by using a new ankle rating score. Hypertrophic synovium, synovitis, or fibrous adhesions were arthroscopically visualized and resected in all cases. The average follow-up was 27 months (range, 6 to 64 months). Thirty-one patients underwent complete evaluation and 29 were evaluated over the telephone. There were 51 excellent, 7 good, 1 fair, and 1 poor results. The diagnosis of chronic soft-tissue impingement of the ankle can be made from an appropriate history, thorough physical examination, and plain radiographs. Ankle arthroscopy with resection of impinging hypertrophic synovium or fibrous bands occurring after an ankle sprain was effective in alleviating pain in athletes.