Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LATERALITY”

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 1,297 records · Page 72Linked to original sources
PubMed2006

Effects of disease severity on response to lateral wedged shoe insole for medial compartment knee osteoarthritis.

OBJECTIVE: To determine the effects of lateral wedged insoles on knee kinetics and kinematics during walking, according to radiographic severity of medial compartment knee osteoarthritis (OA). DESIGN: A prospective case control study of patients with medial compartment OA of the knee. SETTING: Gait analysis laboratory in a university hospital. PARTICIPANTS: Forty-six medial compartment knees with OA of 23 patients with bilateral disease and 38 knees of 19 age-matched healthy subjects as controls. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: We measured the peak external adduction moment at the knee during the stance phase of gait and the first acceleration peak after heel strike at the lateral side of the femoral condyles. Kellgren and Lawrence grading system was used for radiographic assessment of OA severity. RESULTS: The mean value of peak external adduction moment of the knee was higher in OA knees than the control. Application of lateral wedged insoles significantly reduced the peak external adduction moment in Kellgren-Lawrence grades I and II knee OA patients. The first acceleration peak value after heel strike in these patients was relatively high compared with the control. Application of lateral wedged insoles significantly reduced the first acceleration peak in Kellgren-Lawrence grades I and II knee OA patients. CONCLUSIONS: The kinetic and kinematic effects of wearing of lateral wedged insoles were significant in Kellgren-Lawrence grades I and II knee OA. The results support the recommendation of use of lateral wedged insoles for patients with early and mild knee OA.

Aged↗
PubMed2006

Lateral trochanteric pain following primary total hip arthroplasty.

The purpose of this study was to evaluate the incidence of lateral trochanteric pain (LTP) following primary total hip arthroplasty (THA) and identify risk factors. From 1993 to 1998, 543 primary THAs were performed for osteoarthritis. Lateral trochanteric pain was identified in 24 (4.4%) of 543 patients. The incidence of LTP with the posterior approach was 1.2% (1/82), and the incidence with the direct lateral approach was 4.9% (23/461). Leg length discrepancy, femoral offset, and heterotopic ossification were not correlated with LTP. No patient required operative treatment. Lateral trochanteric pain after primary THA was significantly more common in females (P < .04) and in patients who had a direct lateral approach (P < .01). Lateral trochanteric pain in this series was effectively treated with nonoperative modalities.

Aged↗
PubMed2006

Lateral patellar contact after total knee arthroplasty: an analysis of the effects on postoperative pain and outcome.

Although medialization of the patellar component during primary total knee arthroplasty (TKA) has been advocated for biomechanical reasons, this can lead to lateral patellar contact with the femoral component. Using blinded radiographic evaluations, we evaluated 980 consecutive primary TKAs performed from 1997 to 1998. The prevalence of lateral patellar contact in this series was found to be 46.1%. Lateral patellar contact was not correlated with significant differences in our measures of outcome (knee score [P = .1066], functional score [P = .2457], or range of motion [P = .2514]). The average pain score in knees with lateral patellar contact was higher (48.1) (less pain) when compared with knees without (46.7). Total knee arthroplasties without lateral patellar contact had a 1.61 times odds of experiencing postoperative pain compared with those TKAs with lateral patellar contact (P = .0025).

Adult↗
PubMed2004

Lateral retinacular release: a survey of the International Patellofemoral Study Group.

PURPOSE: The purpose of this investigation was to determine current views regarding lateral release among experienced knee surgeons with a specific interest in the patellofemoral joint. TYPE OF STUDY: Scientific survey. METHODS: A questionnaire was developed and mailed to all members of an international group with a specific interest in disorders of the patellofemoral joint. Frequencies and percentages of responses were calculated for each question to determine surgeon consensus. We measured agreement among responses using the kappa statistic. This provided an indication of consistency for each question as well as correlation among the responses to different questions. RESULTS: The survey response rate was 60%. Isolated lateral release was estimated to account for only 1 to 5 surgical cases per respondent per year, or 2% of cases performed annually. In the setting of arthroscopy or exploration, 74% of respondents believed that lateral release calls for specific informed consent. Strong consensus was found that objective evidence is needed to justify lateral release, but agreement was poor as to what clinical evidence provides the most appropriate indication for the procedure. CONCLUSIONS: Even among experienced knee surgeons with a special interest in diseases of the patellofemoral articulation, isolated lateral release is rarely performed. Strong consensus was found that isolated lateral release should not be undertaken without prior planning in the form of objective clinical indications and preoperative informed consent. LEVEL OF EVIDENCE: Level V.

Arthroscopy↗
PubMed2005

Long-term results of lateral retinacular release.

PURPOSE: We evaluated the outcomes of lateral retinacular release (LRR) after a long-term follow-up period of 5 to 12 years. TYPE OF STUDY: Long-term retrospective clinical follow-up study. PATIENTS AND METHODS: Between 1986 and 1994, 120 LRRs were performed in the Orthopaedic Department of the Catholic University of Rome. A total of 100 patients were evaluated. We divided the patients into 2 groups: group I contained 50 patients with patellar pain and no signs of instability; the remaining 50 patients, with clear signs of patellar instability, made up group II. Standard weight-bearing radiographs, axial views of the knee at 45 degrees , and dynamic computed tomography scans were performed in all patients preoperatively and at follow-up evaluation. Chondral damage was classified at the time of lateral release according to the criteria of Outerbridge and Dunlop. We used the Lysholm II score, which was modified for patellofemoral pathology and a clinical grading system of Busch and de Haven, to evaluate clinical outcomes at follow-up evaluation. RESULTS: In group I (pain), 70% reported satisfactory outcomes at follow-up evaluation compared with 50% in group II (P < .05) (instability). Compared with a previously published analysis of 3-year outcomes in this same patient population, there was very little change in group I patients, whereas group II showed a significant decrease in good outcomes over time. The worst results were obtained in cases with serious cartilage damage and exposure of the subchondral bone at the time of lateral release. CONCLUSIONS: LRR is a procedure offering a good percentage of success in the management of a stable patella with excessive lateral pressure and elective location of pain on the lateral retinaculum. In patellar instability the results are less favorable in long-term follow-up evaluation. The presence of high-grade joint surface injury is a poor prognostic indicator for lateral release. LEVEL OF EVIDENCE: Level IV.

Adult↗
PubMed2006

Clinical outcomes following isolated lateral meniscal allograft transplantation.

PURPOSE: The purpose of our study was to determine the clinical outcomes following isolated lateral meniscal allograft transplantation. METHODS: Thirty-two patients were retrospectively reviewed following isolated lateral meniscal allograft transplantation. Twenty-five were available for subjective follow-up, and 17 were available for a complete physical examination and postoperative radiographs. The average duration of follow-up was 3.3 years (range, 2 to 6 years), and the average age of the subjects was 30 years (range, 19 to 45 years). In all, 17 patients had bony fixation and 8 had suture fixation of the anterior and posterior horns of the meniscal allograft. RESULTS: Ninety-six percent of patients believed that their overall function and activity level were improved following surgery. Short Form-36 (SF-36) physical and mental component summary scores for these subjects were higher than age- and sex-matched scores from the US population. Joint space narrowing of the transplanted lateral compartments was not significantly different when compared with the joint space narrowing of the lateral compartment of the contralateral knee. In addition, preoperative and postoperative radiographic joint space measurements of the involved lateral compartment were significantly associated with subjective assessment, symptoms, sports activity score, Lysholm score, and final International Knee Documentation Committee (IKDC) rating at latest follow-up. Finally, patients fixed with the bony technique had significantly better range of motion, according to IKDC criteria at latest follow-up, compared with the suture fixation group. CONCLUSIONS: Our results suggest that isolated meniscal allograft transplantation can be a beneficial procedure in properly selected symptomatic patients with a lateral meniscus-deficient knee. The data also suggest that earlier meniscal transplantation, before the onset of significant joint space narrowing, may result in improved outcomes. Finally, bony fixation may have a significant advantage over suture fixation, particularly with regard to knee range of motion. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Adult↗
PubMed2005

Hemispheric specialization and dual processing in strongly versus weakly lateralized chicks.

Lateralization of various functions is well established in the domestic chick and other vertebrates. The function of lateralization is a question under investigation now. In a previous study, it was shown that chicks incubated in the dark (Da), which prevents the development of lateralization of visual foraging and predator detection, did not perform well when two tasks requiring simultaneous use of the expertise of the right and left eye systems were presented. Performance of a task requiring the chick to find grains against a background of pebbles deteriorated in the Da chicks in the presence of a predator. In the study reported here, the two simultaneous tasks were tested in both binocular and monocular conditions to establish the role of each eye system. Learning of the pebble-floor task was poor in Da chicks tested binocularly or monocularly and in the light-exposed (Li) chicks using the left eye (LE). The time taken to complete the pebble-floor task in the presence of a predator was significantly longer for the Da chicks. This was because pecking was interrupted for longer times when the predator was presented, and the Da chicks made more distress calls than the Li. The latency to detect the predator was longest in the Li chicks using the right eye (RE) (i.e., the Li were lateralized). In the Li chicks, sustained initial viewing of the predator was by the LE. There was no LE/RE difference in the Da chicks. The intensity of responses decreased with continued presentation of the predator but forced use of the RE slowed this habituation. Exposure to light before hatching affects lateralization of both learning of the pebble-floor task and the detection of an overhead predator. Attending to the foraging and predator vigilance tasks simultaneously is impaired in the Da chicks and the superior ability of Li (lateralized) chicks is due to a specific effect of light stimulation of the RE prior to hatching. We have shown that superior performance on the dual task results from the ability to allocate food searching to one hemisphere (left) and predator vigilance to the other (right) hemisphere, achieved only by Li chicks.

Animals↗
PubMed2006

Preservation of lateral thoracic artery to improve vascular supply of distal skin without compromising pedicle length in harvesting pectoralis major myocutaneous flap.

The pectoralis major myocutaneous (PM) flap is supplied by three arterial systems. The lower chest skin of the PM flap is mainly supplied by the branches of lateral thoracic artery and internal mammary artery. The conventional harvesting technique for head and neck reconstruction utilizes single arterial supply from the pectoral branch of thoracoacromial artery. The distal skin island of PM flap is therefore compromised and requires indirect blood supply by communicating vessels. In harvesting the PM flap, the pectoralis minor muscle is divided to preserve the lateral thoracic artery and its blood supply to the lateral distal skin island of PM flap without compromising the pedicle length for head and neck reconstruction. Six PM flaps were harvested for reconstruction of head and neck defects with preservation of both the pectoral artery and lateral thoracic artery. The focal pint of swing of all six flaps was at the same point just below the mid-point of clavicle for both pectoral artery and lateral thoracic artery. The flaps can reach the oral cavity, tonsil or hypopharynx without limitation and there is no flap necrosis. In conclusion, the lateral thoracic artery can be preserved without compromising the pedicle length of PM flap. It is a recommended technique to improve the blood supply to the distal skin of PM flap.

Head and Neck Neoplasms↗
PubMed2005

Effects of GABA(B), 5-HT(1A), and 5-HT(2) receptor stimulation on activation and inhibition of the rat lateral amygdala following medial geniculate nucleus stimulation in vivo.

The input from the medial geniculate nucleus of the thalamus (MGN) to the lateral amygdala is known to be important in the regulation of fear and anxiety. Modulation of this pathway may be useful for the treatment of anxiety disorders. We set out to determine whether simple extracellular electrophysiological techniques could be used to study pharmacological modulation of this pathway in vivo. We studied the effects of GABA(B), 5-HT(1), and 5-HT(2) receptor agonists on activity in the lateral amygdala following stimulation of the MGN in isoflurane-anaesthetised rats. Electrical stimulation of the MGN evoked a characteristic biphasic field potential in the lateral amygdala. Baclofen (10 mg kg(-1), iv) inhibited the evoked potential with an effect that was most marked on the positive-going component (80+/-9% inhibition; P<0.05). Baclofen also significantly reduced paired-pulse inhibition of the negative-going component at short interpulse intervals (<200 ms). The 5-HT(1A) receptor ligands, 8-OH-DPAT (60 microg kg(-1), iv) and WAY-100635 (0.5 mg kg(-1), iv) were without effect on evoked responses or paired-pulse relationship. In contrast, the 5-HT(2) receptor agonist, DOI, caused a rapid inhibition of the field potential (to 59.33+/-11.41% of the baseline response; P<0.05). This effect was blocked by ketanserin, either following systemic (0.5 mg kg(-1), iv) or intra-amygdala administration. These results show that GABA(B) and 5-HT(2) receptor agonists can modulate activation of the lateral amygdala following MGN stimulation; furthermore, GABA(B) receptor agonists appear to have a profound effect on local circuit inhibition within the lateral amygdala. The results support the use of in vivo field potential recording within the MGN-lateral amygdala pathway to evaluate this as a possible site of action for novel anxiolytic drugs.

8-Hydroxy-2-(di-n-propylamino)tetralin↗
PubMed2005

Progesterone's 5 alpha-reduced metabolite, 3 alpha,5 alpha-THP, mediates lateral displacement of hamsters.

5 alpha-Pregnan-3 alpha-ol-20-one (3 alpha,5 alpha-THP), progesterone (P4)'s 5 alpha-reduced, 3 alpha-hydroxysteroid oxidoreduced product, facilitates lordosis of rodents in part via agonist-like actions at GABA(A)/benzodiazepine receptor complexes in the ventral tegmental area (VTA). Whether 3 alpha,5 alpha-THP influences another reproductively-relevant behavior, lateral displacement, of hamsters was investigated. Lateral displacement is the movement that female hamsters make with their perineum towards male-like tactile stimulation. This behavior facilitates, and is essential for, successful mating. Hamsters in behavioral estrus had greater lateral displacement responses when endogenous progestin levels were elevated compared to when progestin levels were lower. Administration of P4, a prohormone for 3 alpha,5 alpha-THP, dose-dependently (500 > 200 > 100, 50, or 0 microg) enhanced lateral displacement of ovariectomized hamsters that had been primed with SC estradiol benzoate (5 or 10 microg). Inhibiting P4's metabolism to 3 alpha,5 alpha-THP by co-administering finasteride, a 5 alpha-reductase inhibitor, or indomethacin, a 3 alpha-hydroxysteroid oxidoreductase inhibitor, either systemically or to the VTA, significantly decreased lateral displacement and midbrain progestin levels of naturally receptive or hormone-primed hamsters compared to controls. These data suggest that lateral displacement is progestin-sensitive and requires the formation of 3 alpha,5 alpha-THP in the midbrain VTA.

Analysis of Variance↗
PubMed2004

Parabrachial inputs to Fos-immunoreactive neurons in the lateral central nucleus of amygdala activated by hypotension: a light and electron microscopic study in the rat.

Morphological features and functional implications of projections of the parabrachial nucleus to the central nucleus of the amygdala were investigated in the rat. The anatomical study was based on injections of the tracers horseradish peroxidase and biotinylated dextran amine. An extremely dense concentration of labeled fibers was found in the lateral and lateral capsular subdivisions of the central nucleus of the amygdala, originating mainly from the external lateral and ventral lateral subnuclei of the parabrachial nucleus. The parabrachial fibers exhibited the morphological characteristic of forming dense pericellular terminal arborizations. The functional implications of this pathway in cardiovascular functions were verified using Fos protein induction in response to hypotension induced by continuous intravenous administration of hydralazine-hydrochloride. In this paradigm, Fos immunoreactivity was found to be confined to the lateral and lateral capsular subdivisions of the central nucleus of the amygdala. Double immunostaining methods were used to visualize, at the electron microscopic level, terminals labeled by biotinylated dextran amine and Fos cell labeling. With this approach, we were able to confirm that Fos-immunoreactive neurons in the central nucleus of the amygdala receive axosomatic terminals from the parabrachial nucleus. The present findings point out that parabrachial inputs to the central nucleus of the amygdala play a relevant role in regulating cardiovascular function.

Amygdala↗
PubMed2005

Lateral and medial amygdala of anuran amphibians and their relation to olfactory and vomeronasal information.

The amygdala of anurans is currently considered as a complex of nuclei that share many features with their counterparts in amniotes. In the present study, the subdivisions of the amygdala that are directly related to olfactory and vomeronasal information, were investigated in the anurans Rana perezi and Xenopus laevis. In particular, the connectivity of the main and accessory olfactory bulbs and their related amygdaloid nuclei was studied by means of in vivo and in vitro tract-tracing with dextran amines. The projections observed from the main olfactory bulb clearly innervate the newly redefined lateral amygdala within the ventral pallium and, to a lesser extent, the rostral portion of the medial amygdala. Injections into the accessory olfactory bulb exclusively revealed projections to the medial amygdala. Tracer applications into the lateral and medial nuclei revealed abundant intra-amygdaloid connections. The dual flow of olfactory and vomeronasal projections throughout the telencephalon was not strictly segregated since the lateral pallium and the lateral amygdala, both receiving olfactory information, were found to project to the medial amygdala (the only target of vomeronasal information), which in turn projects to the lateral amygdala. Additionally, both the lateral and the medial amygdala strongly project to the hypothalamus through the anuran equivalent of the stria terminalis. The main hodological features found in the present study suggest that forerunners of the olfactory and vomeronasal amygdaloid nuclei can be distinguished in anurans. This supports the notion that all tetrapods share a common pattern of organization of the amygdaloid complex, which links environmental (olfactory/vomeronasal) information and the behavioural response of the animal.

Amygdala↗
PubMed2004

Q-angle undervalued? The relationship between Q-angle and medio-lateral position of the patella.

BACKGROUND: For an accurate quadriceps angle measurement, the patella must be centralised in the femoral trochlear groove, numerous authors have described lateral displacement of the patella in patellofemoral pain patients, this leads to the intriguing possibility that the Q-angle might be undervalued within patellofemoral pain patients who have laterally displaced patella. METHOD: 109 asymptomatic subjects (51 male, 58 female) were assessed. Medio-lateral patella position was measured using a previous validated method and Q-angle was measured in standing with the quadriceps relaxed. FINDINGS: Mean Q-angle was 11.6 degrees (SD 5.2) left knee, 11.3 degrees (SD 4.9) right knee in the male subjects and 14.4 degrees (SD 5.2) left knee, 13.3 degrees (SD 5.5) right knee for female subjects. 40 females and 28 males had laterally displaced patellae. 13 subjects had centrally placed patellae (7 females, 6 males) with 28 subjects having medially displaced patellae (11 females, 17 males). Recalculation of Q-angle for the laterally displaced group brought about a statistically significant increase in angle. In the medial displaced group failed to produce a statistically significant decrease. INTERPRETATION: The adjusted Q-angle values for medially and neutral placed patellae brought the values very much into the centre of the reported ranges for Q-angles. After adjustment for lateral patella displacement, Q-angle values were towards the under end of values reported as normal, especially female values which were close to the previously reported pathological cut off point. Because of the inverse relationship between quadriceps strength and the magnitude of Q-angle and quadriceps crucial role in the aetiology of patellofemoral pain, any method which improves the reliability and applicability of Q-angle measurement could prove useful in investigations into the aetiology of and outcome from treatment of patellofemoral pain syndrome.

Adolescent↗
PubMed2007

A biomechanical analysis of the effect of lateral column lengthening calcaneal osteotomy on the flat foot.

BACKGROUND: Biomechanical models have been used to study the plantar aponeurosis, medial arch height, subtalar motion, medial displacement calcaneal osteotomy, subtalar arthroereisis and the distribution of forces in the normal and flat foot. The objective was to examine the hypothesis that increased load on the medial arch in the adult flat foot can be reduced through a 10mm lateral column lengthening calcaneal osteotomy 10 mm proximal from the calcaneal cuboid joint. METHODS: A three dimensional multisegment biomechanical model was used with anatomical data from a normal foot, a flat foot and a foot corrected with a 10mm lateral column lengthening calcaneal osteotomy. The response of a normal foot, a flat foot and a flat foot with a 10mm lateral column lengthening calcaneal osteotomy to an applied load of 683 N was analyzed using the biomechanical model. Data for the biomechanical model was obtained from a cadaver foot using the direct linear transformation method. Direct linear transformation uses multiple cameras to determine the spatial location of anatomical landmarks. FINDINGS: Load on the first metatarsal increases to 37% body weight in the flat foot compared to 12% for the normal foot and the moment about the talo-navicular joint increases from 5.6 N m to 21.6 N m. Lateral column lengthening shifts the load toward the lateral column, decreasing load on the first metatarsal to 10% and decreasing the moment about the talo-navicular joint to 8.1 N m. INTERPRETATION: The analysis shows that a 10mm lateral column lengthening calcaneal osteotomy reduces the excess force on the medial arch in an adult flat foot and adds biomechanical rationale to this clinical procedure.

Biomechanical Phenomena↗
PubMed2004

Maximizing aesthetics in lateral-tension abdominoplasty and body lifts.

The high-lateral-tension abdominoplasty addresses the practical and theoretic faults of standard abdominoplasty design. Key features include limited direct undermining, increased lateral skin resection with highest-tension wound closure along lateral limbs, two-layer superficial fascial system repair, and significant truncal liposuction when needed. The high-lateral-tension design limits the unfavorable features of standard abdominoplasty and produces balanced natural aesthetic contours. The high-lateral-tension abdominoplasty is the foundation for treatment of more generalized relaxation problems in the circumferential trunk and thighs. For more significant thigh laxity and buttock ptosis, the lateral-tension abdominoplasty is combined with the transverse thigh/buttock lift to produce the lower body lift #2.

Abdominal Wall↗
PubMed2005

Identification of distinct electrocardiographic patterns from the basal left ventricle: distinguishing medial and lateral sites of origin in patients with idiopathic ventricular tachycardia.

BACKGROUND: Idiopathic ventricular tachycardias (IVTs) can originate from the basal left ventricle (LV). OBJECTIVE: To determine if using magnetic electroanatomic mapping (MEAM) for accurate localization (1) unique ECG morphologies on pace maps from medial and lateral sites in basal LV could be identified and (2) this ECG information would facilitate VT localization. METHODS: In 12 patients with structurally normal hearts undergoing ablation for IVT, detailed MEAM of LV was constructed in sinus rhythm and pace-mapping was done from the septal-parahisian (S-P) region, aortomitral continuity (AMC), and superior, superolateral, and lateral mitral annular (MA) locations. Pace maps were analyzed for ECG morphologies in limb leads and transition patterns in precordial leads. RESULTS: Medial pacing sites (S-P and AMC) compared with lateral sites (superolateral and lateral MA) demonstrated narrower QRS complexes (134 +/- 24 msec vs. 182 +/- 18 msec; P < .05) with initial negative forces in lead V1 and predominantly positive forces in lead I (amplitude 0.59 +/- 0.27 mV vs. 0.16 +/- 0.34 mV; P < .05). The ratio of QRS complexes in leads II and III was >1 for all (12 of 12) S-P pace maps and 11 of 12 lateral MA pace maps but remained < or =1 for pace maps from 10 of 12 AMC locations, 11 of 12 superior MA locations, and 10 of 11 superolateral MA locations. Using these ECG criteria, a blinded reviewer was able to accurately localize the site of origin (SOO) of clinical arrhythmia (successful ablation site on MEAM) in 10 of 12 cases (83%) of IVT originating from basal LV. CONCLUSION: Pace maps from basal LV endocardium manifest site-dependent ECG morphologies that can help differentiate medial from lateral locations and can predict the SOO of clinical arrhythmias from this region.

Adult↗
PubMed2005

Lateral rectus resections in divergence palsy: results of long-term follow-up.

INTRODUCTION: Lateral rectus resections have been previously advocated as surgical options to treat patients with divergence palsy who do not respond well to prisms. This study was undertaken to review the results and long-term follow-up of patients with divergence palsy who underwent lateral rectus resections at our institution. METHODS: Retrospective review of 29 patients (age 35-83 years) with divergence palsy. Five subjects underwent unilateral lateral rectus resection between 4.5 and 5.5 mm on adjustable suture and 24 subjects underwent bilateral lateral rectus resection between 3 and 7 mm on adjustable sutures. RESULTS: Preoperatively, all patients had diplopia at distance and an esodeviation, which was greater at distance (mean 14.7 +/- 5.1Delta) than at near (mean 4.7 +/- 3.5Delta). Twenty-five subjects had previously been treated with prisms. Postoperative follow-up period ranged from 6 to 96 months (mean 38.7 +/- 27.3 months). The angle of deviation at distance was significantly reduced to -0.1 +/- 3.2Delta postoperatively ( P < 0.0001). The angle of deviation at near reduced significantly to -2.2 +/- 3.3Delta postoperatively ( P < 0.0001). No patient was overcorrected for near. Two patients experienced recurrent postoperative diplopia at distance subsequently at 1 and 4 years, which was corrected with prism glasses and lateral rectus re-resection. CONCLUSION: Lateral rectus resection in patients with divergence palsy is an effective and stable procedure in patients with divergence palsy over long-term follow-up periods, with minimal risk of overcorrections at near.

Adult↗
PubMed2004

Mechanical and metabolic requirements for active lateral stabilization in human walking.

Walking appears to be passively unstable in the lateral direction, requiring active feedback control for stability. The central nervous system may control stability by adjusting medio-lateral foot placement, but potentially with a metabolic cost. This cost increases with narrow steps and may affect the preferred step width. We hypothesized that external stabilization of the body would reduce the active control needed, thereby decreasing metabolic cost and preferred step width. To test these hypotheses, we provided external lateral stabilization, using springs pulling bilaterally from the waist, to human subjects walking on a force treadmill at 1.25 m/s. Ten subjects walked, with and without stabilization, at a prescribed step width of zero and also at their preferred step width. We measured metabolic cost using indirect calorimetry, and step width from force treadmill data. We found that at the prescribed zero step width, external stabilization resulted in a 33% decrease in step width variability (root-mean-square) and a 9.2% decrease in metabolic cost. In the preferred step width conditions, external stabilization caused subjects to prefer a 47% narrower step width, with a 32% decrease in step width variability and a 5.7% decrease in metabolic cost. These results suggest that (a). human walking requires active lateral stabilization, (b). body lateral motion is partially stabilized via medio-lateral foot placement, (c). active stabilization exacts a modest metabolic cost, and (d). humans avoid narrow step widths because they are less stable.

Adult↗