Maximum Abduction Research Articles

New dynamic three‐dimensional MRI technique for shoulder kinematic analysis

To establish a new imaging technique using dynamic MRI three-dimensional (3D) volumetric acquisition in real-time, on six normal shoulders for the analysis of the 3D shoulder kinematics during continuous motion. At first, a standard static acquisition was performed. Then, fast images were obtained with a multi-slice 3D balanced gradient echo sequence to get a real time series during the initial phase of shoulder abduction. Subsequently, the images were reconstructed; registered and the translational patterns of the humeral head relative to the glenoid and the size of the subacromial space were calculated. Additionally, the intraobserver reproducibility was tested. The maximal abduction was on average 43° (30° to 60°) and the mean width of the subacromial space was 7.7 mm (SD: ±1.2 mm). Difference between extreme values and average values was low, respectively 2.5 mm on X-axis, 2 mm on Y-axis, 1.4 mm for the width of the subacromial space and 1.2° for the measure of the glenohumeral abduction. This study reported a dynamic MRI protocol for the monitoring of shoulder 3D kinematics during continuous movement. The results suggest that there is no superior shift of the humeral head during the first phase of abduction.

The Effect of Velocity on Load Range during Isokinetic Hip Abduction and Adduction Exercise

The purpose of this study was to quantify the components of acceleration, load range and deceleration through a velocity spectrum during concentric hip abduction and adduction isokinetic exercise, and to investigate the effect of load range on peak torque and work done. 16 male healthy subjects performed 3 maximal concentric reciprocal hip abduction and adduction gravity corrected repetitions in a fixed order at 60, 120, 180, 240, 300, 360 and 420° · s-1, with a 30 s rest between velocities. Hip abduction and adduction results revealed that load range significantly decreased while acceleration and deceleration ROM significantly increased (p<0.05) with each increase in velocity. When the total peak torque data was corrected for load range there was a significant decrease (p<0.05) in peak torque at velocities of 300° · s-1 and above, for both hip abduction and adduction. Load range correction also resulted in a significant decrease (p<0.05) in work done at velocities of 120° · s-1 and above, for both hip abduction and adduction. The results demonstrate an inverse relationship between isokinetic velocity and load range during concentric hip abduction and adduction, and suggest a need for the clinician to carefully consider velocity selection when performing exercise on an isokinetic device.

Time of Day Does Not Modulate Improvements in Motor Performance following a Repetitive Ballistic Motor Training Task

Repetitive performance of a task can result in learning. The neural mechanisms underpinning such use-dependent plasticity are influenced by several neuromodulators. Variations in neuromodulator levels may contribute to the variability in performance outcomes following training. Circulating levels of the neuromodulator cortisol change throughout the day. High cortisol levels inhibit neuroplasticity induced with a transcranial magnetic stimulation (TMS) paradigm that has similarities to use-dependent plasticity. The present study investigated whether performance changes following a motor training task are modulated by time of day and/or changes in endogenous cortisol levels. Motor training involving 30 minutes of repeated maximum left thumb abduction was undertaken by twenty-two participants twice, once in the morning (8 AM) and once in the evening (8 PM) on separate occasions. Saliva was assayed for cortisol concentration. Motor performance, quantified by measuring maximum left thumb abduction acceleration, significantly increased by 28% following training. Neuroplastic changes in corticomotor excitability of abductor pollicis brevis, quantified with TMS, increased significantly by 23% following training. Training-related motor performance improvements and neuroplasticity were unaffected by time of day and salivary cortisol concentration. Although similar neural elements and processes contribute to motor learning, training-induced neuroplasticity, and TMS-induced neuroplasticity, our findings suggest that the influence of time of day and cortisol differs for these three interventions.

Sidestep cutting technique and knee abduction loading: implications for ACL prevention exercises

BackgroundSidestep cutting technique is essential in programmes to prevent anterior cruciate ligament (ACL) injury. A better understanding of how technique affects potentially harmful joint loading may improve prevention programmes. The...

The influence of hip strength on gluteal activity and lower extremity kinematics

The effects of hip muscle strength and activation on anterior cruciate ligament injury biomechanics, particularly knee valgus loading, have been reported in isolation and with equivocal results. However, the combination of these factors influences joint biomechanics. This investigation evaluated the influence of hip strength on gluteal activation and knee valgus motion. Maximal isometric hip abduction (ABD) and external rotation (ER) contractions were used to define High and Low strength groups. Knee kinematics and gluteus maximus (GMax) and medius (GMed) EMG amplitudes obtained during landing were compared between High and Low strength groups after controlling for the potential confounding influence of sex. Knee valgus motion did not differ between the High and Low hip ABD and ER strength groups. However, the Low ABD and ER strength groups displayed greater GMed and GMax EMG amplitudes, respectively, compared to the High strength groups. These findings suggest that weaker individuals compensate for a lack of force production via heightened neural drive. As such, hip muscle strength influences knee valgus motion indirectly by determining neural drive requirements.

Neck and shoulder function in patients treated for oral malignancies: A 1‐year prospective cohort study

Neck and shoulder complaints can be a direct result of a neck dissection. Maximal active lateral flexion of the neck, forward flexion and abduction of the shoulder, and self-perceived function were determined in 145 patients treated for oral cancer. No short-term influence of radiotherapy was found on measured range of motion and self-perceived neck and shoulder function (p > .05). One year after a bilateral neck dissection, patients showed deteriorated lateral flexion of the neck, whereas patients treated with a unilateral modified radical neck dissection still reported pain during neck movements. Maximal forward flexion of the shoulder recovered to the level of healthy controls, but maximal abduction was still reduced in all patients. Neck dissection, tumor site, and extensive reconstruction are related to deterioration of shoulder function shortly after intervention. Maximal active shoulder abduction was affected most.

An in vivo kinematic study of the reverse shoulder joint replacement.

As of now few studies have investigated the kinematics of the reverse shoulder arthroplasty (RSA) in patients and none on how this may be affected by glenosphere shape or size. There have been a few biomechanical studies evaluating the RSA. These studies have modelled and estimated that a large amount of movement is available at the glenohumeral articulation, when using a standard glenosphere, with even more movement using an eccentric or large glenosphere. However, the in vivo kinematics of the RSA has not been determined. Therefore, we conducted a study to assess the in vivo kinematics of the RSA and to observe what affect the glenosphere type would have. Areas of specific interest were the maximal abduction, the ratio of glenohumeral to scapulothoracic motion, and an observation of what occurs during notching. We obtained 18 patients who had high functioning reverse shoulder replacements, with surgery greater than a year ago. We assessed the kinematics, first with fluoroscopy, where we obtained 5 images at various levels of abduction. Then, at the same sitting, electromagnetic sensors were placed on the lateral epicondyle, acromion and base of the scapular spine. These sensors were attached to the Polhemus 3space tracking system that allowed us to measure the movement of the humerus and the movement of scapula during cycles of abduction. Our results demonstrated that the RSA is able to reproduce kinematics similar to the quoted physiological kinematics. Eccentric glenospheres had higher abduction and are less likely to experience superior impingement of the humerus on the under surface of the acromion or develop the more severe stages of notching. The range of movement in our study was highest in the 36-mm eccentric glenospheres and lowest in the 44-mm concentric glenospheres. Notching, although not associated with a poor outcome score or a lower range of movement was more prevalent in patients whose first phase of movement, consisted mainly of scapulothoracic motion.

Abduction in Internal Rotation: A Test for the Diagnosis of Axillary Nerve Palsy

To describe and validate the use of a test of abduction in internal rotation for the assessment of axillary nerve injury. A total of 14 male patients with a mean age of 29 years (SD ± 6 y), with axillary nerve lesions lasting an average of 6 months, participated. We measured their shoulder range of motion. In the upright position, with the trunk bending forward, we asked our patients to actively extend the shoulder (swallowtail test), and then we extended the shoulders and asked each patient to hold them in that position (deltoid extension lag test). For the abduction in internal rotation test, we asked patients to abduct the shoulder in internal rotation. If full abduction compared with the normal contralateral side was not possible, the examiner passively held the affected limb in maximal abduction and internal rotation. The patient was instructed to maintain the position when the examiner released the limb. In each test, any lag compared with the normal side accounted for deltoid palsy. All patients exhibited abduction beyond horizontal and full external rotation. The swallowtail test and the deltoid extension lag test identified the axillary nerve lesion in 10 of 14 patients. The abduction in internal rotation test recognized the axillary nerve injury in all 14. The average difference in the range of abduction in internal rotation between the normal and affected side was 37° (abduction lag). Compensatory abduction in axillary nerve palsy has been attributed to the action of the supraspinatus, biceps, coracobrachialis, and pectoralis major. During abduction in internal rotation, compensatory abduction is impaired, clearly indicating deltoid muscle dysfunction.

The effects of symmetric and asymmetric foot placements on sit-to-stand joint moments

The purpose of this study was to determine the effects of symmetric and asymmetric foot placements on joint moments during sit-to-stand movements. Three symmetric (foot-neutral, foot-back, and foot-intermediate) and three asymmetric foot placements (preferred stagger, nonpreferred stagger, and intermediate stagger) were tested. Standard (46cm) and low (41cm) seat heights were chosen to represent an average public seat height and a 10% lower seat height. Using inverse dynamics, maximum ankle plantarflexion, knee extension, hip extension, and hip abduction moments were calculated. Hip extension moments were significantly increased when using foot-neutral as compared to foot-back. Ankle plantarflexion and knee extension moments were significantly increased when a foot was placed in the posterior position as compared to the anterior position for preferred and nonpreferred stagger. Knee extension moments were significantly increased at the low seat height as compared to the standard seat height. When shifting the feet anterior or posterior for symmetric placements during sit-to-stand, the most dramatic effect was an increase in hip extension moments when the feet are shifted anteriorly. Utilizing asymmetric foot placements during sit-to-stand produced increases in ankle plantarflexion and knee extension moments for the posteriorly placed limb, with reductions in the anteriorly placed limb.

Dynamic Imaging and Function of Partial Supraspinatus Tendon Tears

It was the purpose of this study to identify and document normal and abnormal supraspinatus tendon function in vivo using real-time ultrasound. We defined 4 groups of 20 individuals each: partial tear (group 1), full-thickness tear (group 2), successfully repaired tear (group 3), and healthy asymptomatic controls (group 4). Except for group 4, all patients underwent magnetic resonance arthrography to confirm the diagnosis. All underwent ultrasound imaging of the supraspinatus tendon with the adducted arm at rest and under maximal isometric abduction. Tendon deformation was dynamically assessed and measured with tendon thickness changes at 0.5, 1, 1.5, and 2 cm from the tendon insertion. The clinical assessment consisted of absolute and relative Constant score, subjective shoulder value, and strength measurements. Without muscle contraction, the tendons of the 4 groups were not of significantly different thickness, with the least variation at 1.5 cm from the insertion site. On contraction, the normal tendon thickness significantly increased at a distance of 2 cm, whereas it did not for the full-thickness and partial supraspinatus tears. Thus contraction of the muscle resulted in measurable deformation of the tendon. Partially torn supraspinatus tendons can be functionally incompetent, leading to a biomechanical deformation of the musculotendinous unit that is not different from that of a unit with a full-thickness tendon tear. The dynamic sonographic finding of a successful repair of a supraspinatus tendon is similar to that of a normal tendon, even though the previously injured muscle appears unable to generate the same strength as a normal muscle. Level III, case-control study.

Effect of Supervised Physiotherapy in Ankylosing Spondylitis

DOI: http://dx.doi.org/10.3329/taj.v15i1.8381 TAJ 2002; 15(1): 37-42

Hemiarthroplasty for Comminuted Proximal Humeral Fractures

To evaluate early functional outcomes of hemiarthroplasty for 3- or 4-part proximal humeral fractures. 16 men and 11 women aged 27 to 83 (mean, 56) years underwent hemiarthroplasty for comminuted 3-part (n=13) or 4-part (n=14) proximal humeral fractures. All the patients reported normal shoulder function prior to injury. The range of shoulder motion and muscle power were evaluated, as were subjective pain and satisfaction (using the UCLA scoring system). At the final follow-up, the mean maximum abduction was 111º (SD, 47º; range, 30º-180º), and the mean maximum forward flexion was 143º (SD, 41º; range, 45º-180º). All patients had radiographic union of the tuberosities. The mean UCLA score was 28; 21 patients attained good-to-excellent scores (≥27), whereas 6 attained lower (fair-to-poor) scores. The mean UCLA score was higher in patients aged <60 (n=13) than those who were older (n=14) [30 vs. 26, p=0.008] and in patients operated after 7 days (n=6) than those operated before 7 days (n=21) [32 vs. 27, p=0.02], but did not differ significantly in terms of gender and fracture type and side. Patient age and gender, fracture type, and injury-to-surgery interval did not have a significant impact on maximum forward flexion and abduction. Early functional outcomes of hemiarthroplasty for comminuted proximal humeral fractures is good in medically fit and cooperative patients.

Value of ultrasonography in diagnosis of pediatric vocal fold paralysis

Objectives To investigate the appearance of the pediatric larynx on ultrasound images and the diagnostic potential of ultrasound in cases of pediatric vocal fold paralysis. Methods First, we confirmed the ultrasonographic features of the laryngeal landmarks in 2 pediatric cadaveric larynxes. Secondly, 45 children were enrolled in a clinical study (13 patients with vocal fold paralysis and 32 normal children). Quantitative analysis of vocal fold mobility was carried out by measuring the maximum glottic angle (MGA) and vocal fold-arytenoid angle (VAA). Results All the paralyzed vocal folds showed abnormal mobility, and were flaccid during breathing and phonation. The rima glottis appeared as a hyperechoic air-column band in ultrasound images during phonation. The mean value of the MGA was 61.47 ± 9.00 in the normal larynx and 42.25 ± 10.41 in the paralyzed larynx. In the affected side of the paralyzed larynx, the VAA in maximum abduction was smaller than that in the normal larynx or in the unaffected side. The median difference of the VAA between maximum abduction and maximum adduction was less than that in the normal larynx. The kappa value was 0.96. Conclusion MGA and VAA are quantitative indicators of vocal fold immobility. Ultrasound is a reliable method of diagnosis of pediatric VFP. To diagnose VFP from an ultrasound image, the criteria are: (1) abnormal mobility (this was the most important and direct evidence), (2) hyperechoic air-column band of the glottic rima during phonation, (3) flaccid vocal fold and (4) asymmetry of the glottal structures.

Noninvasive assessment of liver fibrosis

Noninvasive assessment of liver fibrosis

Changes in the intra-articular pressure inside the radiocarpal joint with different volumes of the intra-articular fluid

Intra-articular pressure was measured in 14 carpal joints of 7 fresh corpses of adults, who had not any diseases of the above joints in their case histories, after introduction of 2, 3 and 5 ml of a fluid inside the joint cavity with the normal position of the hand, as well as after its maximum flexion, extension, adduction and abduction. It was found out that the lowest pressure in the above joint was observed in cases of the neutral hand position, which was accepted to be with 5° of dorsal flexion and 10. of ulnar deviation. The maximum extension and abduction resulted in the most significant rise of pressure: more than 10 times versus the neutral position. The maximum flexion and adduction were accompanied with an increase of intra-articular pressure too. A strong positive correlation was demonstrated between intra-articular pressure and fluid volume in the joint in cases of the examined hand positions. The volume of the intra-articular cavity of the radiocarpal joint was approximately determined as equal to 2 cm3.

Effect of shoulder taping on maximum shoulder external and internal rotation range in uninjured and previously injured overhead athletes during a seated throw

The purpose of our study was to investigate whether shoulder taping affects shoulder kinematics in injured and previously injured overhead athletes during a seated throw. Twenty-six overhead college athletes threw a handball three times with and without tape, while seated on a chair. An 8-camera Vicon Motion Capture system recorded markers placed on the upper limb and trunk during each of the throwing conditions. Scaled musculoskeletal models of the upper limb were created using OpenSim and inverse kinematics used to obtain relevant joint angles. Shoulder taping had no main effect on external (ER) and internal (IR) rotation range (ROM) of the shoulder, but a significant interaction effect was found (p = 0.003 and 0.02, respectively), depending on previous injury status, whereby both the ER and IR ROM of the shoulder in the group of previously injured athletes decreased when taped (143-138° and 54-51°, respectively), but increased in the group who had never been injured (131-135° and 42-44°, respectively). Maximum abduction range and ball velocity were not affected by the application of shoulder taping, regardless of previous injury status. Thus, application of shoulder taping has a differential effect on maximum shoulder ER and IR ROM during throwing depending on previous injury status. These findings have implications for returning athletes to sport after injury and for screening athletes at risk of injury.

SHART: shoulder hyperabduction radiological test

To evaluate and quantify laxity of the inferior glenohumeral ligament (IGHL) in post-traumatic anterior instability of the shoulder with the shoulder hyperabduction radiological test (SHART) and correlate it with arthroscopic findings. This prospective study included 21 patients undergoing arthroscopic stabilization for anteroinferior shoulder instability. The SHART test was performed as follows: a bilateral AP radiograph was performed in the supine position, and radiographs were compared. The shoulder was positioned in passive maximum abduction in neutral rotation, and neither general nor regional anesthesia was used. The angle between the axis of the humeral shaft and the line drawn between the lateral border of the scapular tubercle and the inferior edge of the glenoid fossa was measured. During arthroscopy, IGHL distension was classified into 4 stages according to the Detrisac classification. Extensive distension was considered to be the stages 3 and 4. The correlation between the SHART test and Detrisac staging was found to be statistically significant (P = 0.02). In the presence of a difference of more than 15° between the pathological and the contralateral shoulder on radiographs, the SHART test shows 87% of IGHL distension, Detrisac stages 3 and 4. We suggest that the SHART test should be added to conventional preoperative imaging tests for anterior instability.

Dynamic loading of the knee and hip joint and compensatory strategies in children and adolescents with varus malalignment

Three-dimensional gait analysis is a diagnostic tool that can be used to gain a better understanding of the relationship between joint loading and the onset or progression of articular cartilage degeneration in subjects with varus malalignment. The purpose of the present study was to investigate knee and hip joint angles and moments in children and adolescents with pathological varus alignment of the knee without signs of knee osteoarthritis (OA). Moreover, we wanted to know if compensatory mechanisms are present in this young patient group. Fourteen, otherwise healthy patients with varus malalignment of the knee and 15 healthy control subjects were analysed. Patients showed a reduced knee extension and a significantly lower maximum knee extension moment in terminal stance compared to controls. The maximum knee adduction moment in mid and terminal stance and the maximum hip abduction moment in loading response were significantly higher in the patient group. In the transverse plane, abnormally increased knee internal rotation and hip external rotation moments were present in patients with varus malalignment. These findings imply that varus malalignment is not an isolated problem in the frontal plane. In contrast to adult patients with established medial knee OA, the young patients assessed in the present study did not show typical compensatory mechanisms such as increased foot progression angle or reduced walking speed. This suggests that children and adolescents with varus malalignment of the knee probably do not need to alter their spatio-temporal gait parameters in order to decrease knee joint loading.

A Comparison of Sung and Spoken Phonation Onset Gestures Using High-Speed Digital Imaging

Phonation onset is important in the maintenance of healthy vocal production for speech and singing. The purpose of this preliminary study was to examine differences in vocal fold vibratory behavior between sung and spoken phonation onset gestures. Given the greater degree of precision required for the abrupt onset sung gestures, we hypothesize that differences exist in the timing and coordination of the vocal fold adductory gesture with the onset of vocal fold vibration. Staccato and German (a modified glottal plosive, so named for its occurrence in German classical singing) onset gestures were compared with breathy, normal, and hard onset gestures, using high-speed digital imaging. Samples were obtained from two subjects with no history of voice disorders (a female trained singer and a male nonsinger). Simultaneous capture of acoustical data confirmed the distinction among gestures. Image data were compared for glottal area configurations, degree of adductory positioning, number of small-amplitude prephonatory oscillations (PPOs), and timing of onset gesture events, the latter marked by maximum vocal fold abduction, maximum adduction, beginning of PPOs, and beginning of steady-state oscillation. Results reveal closer adductory positioning of the vocal folds for the staccato and German gestures. The data also suggest a direct relationship between the degree of adductory positioning and the number of PPOs. Results for the timing of onset gesture events suggest a relationship between discrete adductory positioning and more evenly spaced PPOs. By contrast, the overlapping of prephonatory adductory positioning with vibration onset revealed more unevenly spaced PPOs. This may support an existing hypothesis that less well-defined boundaries interfere with normal modes of vibration of the vocal fold tissue.

Gluteus medius strength, endurance, and co-activation in the development of low back pain during prolonged standing

This study measured gluteus medius (GM) strength and endurance before and after a 2 h prolonged standing task in previously asymptomatic individuals, to compare between individuals who did and did not report pain in the low back. Twenty-four participants without a history of low back pain stood in a constrained area for 2 h. Before and after the standing protocol, participant’s maximal hip abduction strength (N) and side-bridge endurance (seconds and GM myoelectric fatigue) were measured. Continuous surface EMG was collected from GM during the 2-h protocol for analysis of bilateral co-activation. Pain in the low back was rated every 15 min with a visual analog scale (VAS). Seventeen of 24 (71%) previously asymptomatic participants developed pain in the low back during the standing protocol. These participants had lower side-bridge endurance ( p = .002), and higher gluteus medius (GM) co-activation ( p = .002) compared to participants who did not develop pain in the low back. Hip abduction strength decreased for both groups following prolonged standing, with no between groups’ difference. Lower side-bridge endurance and hip abduction strength were significantly associated with higher GM co-activation (adjusted r 2 = .34), but not pain levels. Side-bridge endurance and GM co-activation, but not hip abduction strength, may have utility in identifying participants likely to develop pain in the low back during prolonged standing. The best training program for increasing GM endurance is unclear.