Normal Muscle Tone Research Articles

Obstructive Sleep Apnea–Hypopnea Syndrome—The Role of Bariatric and Maxillofacial Surgeries

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a complex disease with multifactorial etiology. It is marked by the occurrence of apnea and hypopnea events caused by repeated obstructions of the upper airways. OSAHS is strongly associated with obesity, and the prevalence of this disease in morbidly obese patients is very high. Nevertheless, not all patients with OSAHS are obese, and for this reason, there may be other anatomical predispositions to airway collapse. In obese patients, fatty deposition in the parapharyngeal region results in airway reduction and predisposes to airway collapse, worsened by neurologic loss of the normal dilator muscle tone of the neck. However, in nonobese patients, specific craniofacial characteristics such as posterior air pharyngeal space, tongue length, hyoid position, and maxillomandibular deficiencies may predispose some people to develop OSAHS. Treatment strategies for OSAHS patients vary from clinical treatment with continuous positive airway pressure, oral appliances, or medications for mild and moderate OSAHS patients, bariatric surgery for severe obese OSAHS patients to maxillomandibular advancement for obese or nonobese OSAHS patients.

Poster 197: Inflammatory Myopathy in a Diabetic Presenting With Foot Drop: A Case Report

Setting: Outpatient clinic. Patient: A 29-year-old man referred for electrodiagnostics with 1 year complaint of progressive foot drop and ataxia. Case Description: Patient has medical history of poorly controlled diabetes type 1 (diagnosed 14 years prior), hyperlipidemia (with current statin use), hypertension, and depression. History of present illness revealed proximal and distal weakness in upper and lower extremities and numbness in stocking and glove distribution. Lumbar magnetic resonance imaging showed disk herniations with no stenosis. The patient denied back pain, radicular pain, muscle aches, or family history of neurologic conditions. Physical exam revealed diffuse atrophy, proximal and distal weakness with trace bilateral ankle dorsiflexion, absent reflexes, and normal muscle tone. Electrodiagnostics revealed a sensorimotor peripheral polyneuropathy with neuropathic findings on electromyography (EMG) without specific myopathic features. Lab studies revealed CPK greater than 1000, elevated aldolase, ESR greater than 100, and a negative rheumatologic panel. Muscle biopsy was suggestive of a chronic myopathy, possibly inflammatory, with features of neurogenic atrophy. Assessment/Results: This patient's clinical picture and diagnostics are suggestive of multifactorial weakness—due to a chronic inflammatory myopathy—polymyositis versus statin-induced myopathy, with a superimposed diabetic neuropathy. The patient has been discontinued from statins, started on corticosteroids and azathioprine, fitted with bilateral ankle foot orthoses, and treated with physical therapy. His functional status remains stable with ongoing treatment. Conclusions: Correlation of thorough history, physical exam, and diagnostics is essential for appropriate diagnosis and treatment. EMG findings for this patient were suggestive of a neuropathic process, while physical exam also suggested a myopathic process. Through laboratory and histologic studies a more complete pathophysiology and treatment plan was formed. It is important to remember that weakness can be multifactorial. Complex cases where history and physical do not correlate with findings necessitate further diagnostic investigation, consideration, and cross-specialty physician collaboration to achieve the best patient outcomes.

Human resting muscle tone (HRMT): Narrative introduction and modern concepts

Human resting muscle (myofascial) tone (HRMT) is the passive tonus or tension of skeletal muscle that derives from its intrinsic (EMG-silent) molecular viscoelastic properties. The word tone has been used to convey varying clinical and physiological features that have led to confusion and controversy. HRMT is the vital low-level, passive tension, and resistance to stretch that contributes importantly to maintain postural stability in balanced equilibrium positions. In contrast, co-contraction of muscle is an active neuromotor control that provides greater levels of tonus for increased stabilization. Functionally, HRMT is integrated with other passive fascial and ligamentous tensional networks of the body to form a biotensegrity system. This review aims to achieve better understandings of HRMT and its functional roles. Nature is frugal and man's adaptations to gravitational forces and erect postures seemingly evolved mechanisms in skeletal muscle tissues to economically enhance stability. Normal passive muscle tone helps to maintain relaxed standing body posture with minimally increased energy costs (circa 7% over supine), and often for prolonged durations without fatigue. Available data infer polymorphic variations in normal myofascial tone. However, few quantitative studies have been performed to establish normal frequency distributions of degrees of myofascial tone. Clinical experience indicates that persons with certain symptomatic musculoskeletal conditions may have palpably increased resting muscle firmness or hardness (EMG-silent), such as that of the upper trapezius in tension-type headache, and the lumbodorsal extensors (hartspann) in degenerative lumbar disc disease and ankylosing spondylitis. In summary, resting skeletal muscle tone is an intrinsic viscoelastic tension exhibited within the body's kinematic chains. It functions inseparably from fascial (i.e., myofascial) tissues and ligamentous structures. Thus, HRMT is a passive myofascial property which operates within networks of tensional tissues, i.e., biotensegrity. This passive tension is the CNS-independent component resulting from intrinsic molecular interactions of the actomyosin filaments in sarcomeric units of skeletal muscle and myofibroblast cells. The overarching CNS-activated muscle contractions generate far greater tensions transmitted by fascial elements. Interdisciplinary research on HRMT and its biodynamics promises greater effectiveness of clinical practitioners and productivity of investigators, which warrants priority attention.

Popliteal Angle in Infants With West Syndrome

The aim of this study was to clarify the relationship between neurologic findings and outcome of patients with West syndrome, focusing on the popliteal angle. The complete neurologic examination, including an assessment of the popliteal angle and muscle tone, was performed on 45 patients with West syndrome. A tight popliteal angle was determined when it was 120 degrees or less. In all 45 patients, abnormal muscle tone was not correlated with any variables. A tight popliteal angle was correlated with seizure persistence, cerebral palsy, and abnormality on magnetic resonance imaging (MRI), as well as severe developmental delay. When limited to the patients with developmental delay, a tight popliteal angle was correlated with severe developmental delay, cerebral palsy, and MRI abnormality, although abnormal muscle tone was not correlated with any items. In the delay group, eight patients had a tight popliteal angle with normal muscle tone. Among them, severe developmental delay was seen in seven (88%), seizure persistence in five (63%), and MRI abnormality in five (63%). These results suggest that a tight popliteal angle might be an indicator of poor neurologic outcome in patients with West syndrome.

A content analysis of physiotherapy for postural control in people with stroke: An observational study

Purpose. The lack of information about the content of therapy packages is a frequent criticism in stroke rehabilitation research. This study aimed to describe, in detail, the content of one aspect of physiotherapy; the rehabilitation of postural control.Methods. The design was a cross-sectional survey and the setting was in 11 NHS Trusts. The participants were 35 stroke physiotherapists working in acute and rehabilitation settings who recorded the treatment of 132 patients in 644 treatment sessions using the Stroke Physiotherapy Intervention Recording Tool. Analysis was carried out by descriptive statistics, one-way ANOVAS and chi-squares which were used to describe content of interventions and effects of the aim of treatment.Results and conclusions. Physiotherapists' clinical practice focused on therapist-led interventions, which aimed to normalize muscle tone and promote normal movement patterns. The most frequent interventions were ‘preparation for treatment’ (n = 1969, 43%), ‘practising balance and walking activities’ (n = 1583, 34%) and ‘practising functional tasks’ (n = 703, 15%). Interventions to encourage independence or activity outside the treatment session were rarely used. This pattern was seen regardless of the aim of treatment (the restoration of sitting balance, standing balance or stepping/walking).

Facilitated oscillatory release—a dynamic method of neuromuscular and ligamentous/articular assessment and treatment

Facilitated oscillatory release is a method and conceptual lens for applying oscillatory force in an osteopathic treatment sequence to normalize muscle tone and articular balance. Not a free standing modality, it has been mostly integrated into the focal treatment style popular with American osteopaths, as an adjunct to high velocity low amplitude (HVLA), muscle energy (MET) or connective tissue release techniques. The concepts can complement many types of bodywork. On review of the scientific literature, it is speculated that rhythmic peripheral afferent input can enable the resetting of normal postural muscle tone. The associated neurophysiologic theory and research may help further validate osteopathic diagnosis and treatment on a wider scale.

Biomechanical adaptation of porcine carotid vascular smooth muscle to hypo and hypertension in vitro

Previous research in arterial remodeling in response to changes in blood pressure seldom included both hyper- and hypotension. To compare the effects of low and high pressure on arterial remodeling and vascular smooth muscle tone and performance, we have utilized an in vitro model. Porcine carotid arteries were cultured for 3 days at 30 and 170 mmHg and compared to controls cultured at 100 mmHg for 1 and 3 days. On the first and last day of culture, pressure-diameter and pressure-wall thickness curves were measured under normal smooth muscle tone using a high-resolution ultrasonic device. Last-day experiments included measurements where vascular smooth muscle was contracted or totally relaxed. From the data wall cross-sectional area, Hudetz elastic modulus and a contraction index related to the diameter reduction under normal smooth muscle tone were calculated. We found that although wall cross-sectional area (indicating wall mass) did not change much, Hudetz elastic modulus was significantly reduced in the 3-day hypotension group. Inspection of the wall contraction index suggests that this is due to a reduction in the vascular smooth muscle tone. Further, the peak of contraction index was found to be shifted to higher pressures in the 3-day 170 mmHg group. We conclude that vascular smooth muscle performance adapts to both hypo- and hypertension at short time scales and can alter the biomechanics of the vascular wall in vitro.

Dopamine receptors in the subthalamic nucleus are involved in the regulation of muscle tone in the rat

The effects of injecting an irreversible dopamine receptor antagonist, N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ) bilaterally into the subthalamic nucleus (STN) on changes in muscle tone and behaviour were investigated. Increased muscle tone (i.e. rigidity) was assessed quantitatively as increases in tonic electromyographic (EMG) activity in the hindlimb muscles of conscious, unrestrained rats. Significant, sustained increases in EMG activity were observed for 3–5 h post-injection in the tibialis and gastrocnemius muscles following injection of EEDQ into the STN. This effect was associated with 73% dopamine D1 and 66% dopamine D2 receptor occupancy in the STN, while dopamine receptors in surrounding regions were minimally occupied. These results provide new evidence that dopamine receptors located in the STN play an important role in the regulation of normal muscle tone.

Recombinant human acid α-glucosidase enzyme therapy for infantile glycogen storage disease type II: Results of a phase I/II clinical trial

Purpose: Infantile glycogen storage disease type II (GSD-II) is a fatal genetic muscle disorder caused by deficiency of acid α-glucosidase (GAA). The purpose of this study was to investigate the safety and efficacy of recombinant human GAA (rhGAA) enzyme therapy for this fatal disorder.Methods: The study was designed as a phase I/II, open-label, single-dose study of rhGAA infused intravenously twice weekly in three infants with infantile GSD-II. rhGAA used in this study was purified from genetically engineered Chinese hamster ovary (CHO) cells overproducing GAA. Adverse effects and efficacy of rhGAA upon cardiac, pulmonary, neurologic, and motor functions were evaluated during 1 year of the trial period. The primary end point assessed was heart failure–free survival at 1 year of age. This was based on historical control data that virtually all patients died of cardiac failure by 1 year of age.Results: The results of more than 250 infusions showed that rhGAA was generally well tolerated. Steady decreases in heart size and maintenance of normal cardiac function for more than 1 year were observed in all three infants. These infants have well passed the critical age of 1 year (currently 16, 18, and 22 months old) and continue to have normal cardiac function. Improvements of skeletal muscle functions were also noted; one patient showed marked improvement and currently has normal muscle tone and strength as well as normal neurologic and Denver developmental evaluations. Muscle biopsies confirmed that dramatic reductions in glycogen accumulation had occurred after rhGAA treatment in this patient.Conclusions: This phase I/II first study of recombinant human GAA derived from CHO cells showed that rhGAA is capable of improving cardiac and skeletal muscle functions in infantile GSD-II patients. Further study will be needed to assess the overall potential of this therapy.

Intramuscular corticosteroid injection for hamstring injuries. A 13-year experience in the National Football League.

The purpose of this study was to assess the safety of intramuscular corticosteroid injection in selected, severe hamstring injuries in professional football players. Clinicians have been reluctant to use corticosteroid injections in or around muscle-tendon units because of concern of incomplete healing or rupture. We retrospectively reviewed the computer database of one National Football League team for all hamstring injuries requiring treatment between January 1985 and January 1998. We found that 431 players had suffered such injury. We developed a clinical grading system to identify hamstring injury severity and to stratify players for treatment. Fifty-eight players (13%) sustained severe, discrete injuries with a palpable defect within the substance of the muscle and were treated with intramuscular injection of corticosteroid and anesthetic. There were no complications related to the injection of corticosteroid. Only nine players (16%) missed any games as a result of their injury. Final examination revealed no strength deficits, normal muscle bulk and tone, and the ability to generate normal power. We believe that the grading system we developed can assist in selection of injury type for injection. Although lack of a control group limits statements of efficacy of injection, our impression is that intramuscular corticosteroid injection hastens players' return to full play and lessens the game and practice time they miss.

Sensitivity of the pendulum test for assessing spasticity in persons with cerebral palsy

The sensitivity of the pendulum test to variation in spasticity in persons with spastic cerebral palsy (CP) was tested in 30 participants with CP and 10 participants without CP (controls) (mean age 13.8 years). The participants with CP were classified into three groups, with normal (mean age 15.9 years), mild/moderate (13.0 years), or severe (23.0 years) muscle tone, as assessed clinically using a modified Ashworth scale. Joint motion during the pendulum test was measured with an electrogoniometer. Muscle relaxation was confirmed using surface EMG. Outcome measures from the pendulum test were (1) number of oscillations, (2) duration of oscillations, (3) excursion of the first backward swing, and (4) relaxation index (first swing excursion/difference between the starting and resting angles). Data were assessed using one‐way analysis of variance. Outcome measures 1 to 3 differed significantly between control participants and participants with CP (p<0.05). The first swing excursion was the best predictor of the degree of spasticity in persons with CP, being significantly different between all groups (p<0.05). The number of oscillations and their duration differentiated between control participants and all participants with CP (p<0.05) but not between participants with CP who had mild/moderate versus severe spasticity (p>0.05). The relaxation index was not a sensitive measure (p>0.05 between most study groups). We conclude that the pendulum test is a valid tool for assessing spasticity in persons with CP and that the first swing excursion is the most sensitive outcome measure.

Sensitivity of the pendulum test for assessing spasticity in persons with cerebral palsy.

The sensitivity of the pendulum test to variation in spasticity in persons with spastic cerebral palsy (CP) was tested in 30 participants with CP and 10 participants without CP (controls) (mean age 13.8 years). The participants with CP were classified into three groups, with normal (mean age 15.9 years), mild/moderate (13.0 years), or severe (23.0 years) muscle tone, as assessed clinically using a modified Ashworth scale. Joint motion during the pendulum test was measured with an electrogoniometer. Muscle relaxation was confirmed using surface EMG. Outcome measures from the pendulum test were (1) number of oscillations, (2) duration of oscillations, (3) excursion of the first backward swing, and (4) relaxation index (first swing excursion/difference between the starting and resting angles). Data were assessed using one-way analysis of variance. Outcome measures 1 to 3 differed significantly between control participants and participants with CP (p<0.05). The first swing excursion was the best predictor of the degree of spasticity in persons with CP, being significantly different between all groups (p<0.05). The number of oscillations and their duration differentiated between control participants and all participants with CP (p<0.05) but not between participants with CP who had mild/moderate versus severe spasticity (p>0.05). The relaxation index was not a sensitive measure (p>0.05 between most study groups). We conclude that the pendulum test is a valid tool for assessing spasticity in persons with CP and that the first swing excursion is the most sensitive outcome measure.

A man with progressive weakness in his legs

A 47-year-old technical project manager, with a history of endocarditis and aortic regurgitation in 1993, developed difficulty with walking in April, 1995. His thighs tired easily and he had difficulty walking up and down stairs. In October, 1995, he noted cramps in his calves, and problems with driving because of weakness in his feet. He had no pain or sensory symptoms. When he first came to our hospital, in November, 1995, his arms had normal muscle bulk, tone, and strength. There was no muscle atrophy in the legs.

Role of serotonin for scoliotic deformity in pinealectomized chicken.

The effect of intraperitoneal injection of 5-hydroxytryptophan (5-HTP) versus control in pinealectomized chickens. To find if the serotonin may have some role in the cause of treatment of idiopathic scoliosis. One of the causes of idiopathic scoliosis is thought to be the disruption of postural reflex. Serotonin has been proposed to have a crucial role in maintaining normal postural muscle tone or postural equilibrium. Forty pinealectomized chickens served as controls, and an additional 40 pinealectomized chickens received daily intraperitoneal injections of 5-hydroxy-tryptophan, a precursor of serotonin, which can pass through the blood-brain barrier. Spine radiographs were examined to measure the scoliotic deformity. Scoliosis developed in all 40 pinealectomized chickens (control), whereas only 28 chickens in the 5-hydroxytryptophan-treated group (6 in severe, 22 in mild) had scoliosis developed. The remaining 12 chickens grew up with normal spines. Most chickens with mild scoliosis did not have curve progression but continued to have wedged vertebrae. Serotonin deficit secondary to a defect of melatonin may have disturbed postural muscle tone or postural equilibrium resulting in scoliosis in pinealectomized chicken. Prevention from the development of scoliosis or its progression in chickens treated with 5-hydroxytryptophan suggests that serotonin may have potential therapeutic value.

The regulation of motor control: an evaluation of the role of dopamine receptors in the substantia nigra.

The importance of the nigrostriatal dopaminergic pathway in motor control is widely accepted and it is generally believed that the motor symptoms of Parkinson's disease result solely from reduced release of dopamine from terminals in the striatum. Over recent years there has been a growing body of evidence which suggests that dendritic dopamine release in the substantia nigra is of importance in the regulation of neuronal activity and behaviour. This evidence is reviewed together with a description of our recent findings that show nigral dopamine receptors are essential for the maintenance of normal muscle tone. It is concluded that current views of the basal ganglia circuitry involved in motor control need to be re-evaluated to take into account these recent reports. A scheme is suggested to explain how dopamine mechanisms in the substantia nigra regulate motor activity.

Quantitative evaluation of normal muscle tone

Forty-eight normal subjects were evaluated for the purpose of objectively quantifying muscle tone. Flexor carpi radialis and extensor digitorum communis electromyographic (EMG) activity was simultaneously recorded during wrist movements imposed by a torque motor. Each session was subdivided into three steps: (1) measurement of the ‘intrinsic stiffness index’ (ISI) at 10 °/s; (2) measurement of the ‘total stiffness index’ (TSI) at 500 °/s; (3) evaluation of the stretch reflex threshold speed (SRTS). No stretch reflex (SR) was found in about half of the subjects, even at the highest speed. ISI was higher in males ( p < 0.001); significant differences in TSI were found between subjects with SR and those without ( p < 0.02); no statistical differences in SRTS were found for either age or gender. ISI, TSI and SRTS, appear to be reliable indices of the range of normal muscle tone for its quantitative assessment.

Survey of a domiciliary stroke rehabilitation service

A previous randomized controlled comparison of hospital-based and domiciliary rehabilitation for stroke patients discharged from hospital (the DOMINO study) found home therapy to be beneficial in a subgroup who had been in hospital on a stroke unit before entering the trial, whereas no benefit was seen in patients who had been on ordinary geriatric or general medical wards. In this study, to explain the findings of the DOMINO study further, the therapy records kept during the DOMINO study of the amount and type of rehabilitation provided by the domiciliary rehabilitation team were examined. More patients who had been on the stroke unit before entering the trial received therapy and they received more and longer visits than those who had been on geriatric or medical wards. The group from the stroke unit were more likely to receive practice in activities of daily living (ADL), assessment for and instruction in the use of aids and appliances, gait re-education, mobility practice and facilitation of normal muscle tone. One possible deduction is that home rehabilitation services should aim to deliver an average of 15-20 visits in six months, since only this amount of therapy was associated with a measurable benefit. The active components of home therapy may be ADL practice, assessment for and instruction in the use of aids and appliances, gait re-education, mobility, mobility practice and facilitation of normal muscle tone.

THE MECHANISM OF SPASTIC MUSCLE HYPERTONUS&lt;subtitle&gt;VARIATION IN REFLEX GAIN OVER THE TIME COURSE OF SPASTICITY&lt;/subtitle&gt;

The electromyographic (EMG) response of the initially passive biceps brachii muscle to imposed extension applied at the elbow was studied in 19 hemiparetic and 12 normal subjects. In relaxed normal subjects, the biceps muscle was found to respond only at displacement velocities above 175 deg/s, with a single early burst of activity in the biceps EMG. In contrast, the hemiparetic subjects, in addition to the early EMG activity, also showed considerable late activity, which persisted even with stretch velocities as low as 35 deg/s. This late activity is a stretch reflex, present in fully plegic arms. It was seen in all spastic subjects in whom the tone of the biceps had been clinically assessed to be raised, but was never observed in subjects with normal muscle tone. The mean level of this EMG response was highly correlated with displacement velocity and its duration to the duration of the applied displacement. It is suggested that this reflex EMG activity is the major factor in the genesis of spastic hypertonus in the arm and that it arises not from a reduction in the threshold of the stretch reflexes of the muscle, but from a pathological increase in stretch reflex gain. It is further shown that this activity is at a high level between the first and third months after the onset of spasticity and that the reflex gain is significantly reduced when spasticity is established for a year or more. It is concluded that, while changes in passive mechanical properties may play a role when spasticity has been established for more than a year, the major cause of spastic muscle hypertonus is a pathological increase in stretch reflex activity.

Systemic hemodynamic effects of endothelin in rats

Endothelin type 1 (ET-1) is an endothelial cell-derived 21-amino acid peptide with potent contractile effects on isolated vascular smooth muscle. The systemic hemodynamic effects of bolus intravenous injections of ET-1 and angiotensin II (ANG II, 300 pmol) were examined in anesthetized male Munich-Wistar rats by measurements of mean arterial (AP) and right atrial (RAP) blood pressures and cardiac index (CI, electromagnetic flowmetry) over a 60-min period. ET-1 induced a biphasic pressure response: transient hypotension occurred in the early phase with all doses, followed by a more prolonged dose-dependent elevation of blood pressure in the late phase. Because CI was unchanged during the early phase, the hypotension resulted from systemic vasodilation. On the other hand, the marked rise in AP produced by 300 pmol of ET-1 in the late phase was associated with a significant fall in CI, and thus total peripheral resistance index (TPRI) increased profoundly. A fall in right atrial pressure and significant hemoconcentration were associated with this pronounced vasoconstrictor effect, suggesting that a contraction of plasma volume contributed to the reduction of CI. Additionally, stroke and minute work indexes and peak flow velocity became significantly reduced in the late phase for the 300-pmol dose of ET-1. When compared with an equimolar dose of ET-1, 300 pmol of ANG II produced a prompt, more marked, but shorter-lived rise in AP with minimal changes in CI, TPRI, RAP, and hematocrit. These results raise the intriguing possibility that endothelin may play a role in both the control of normal vascular smooth muscle tone and in the pathogenesis of vasospastic disorders.

Duck Wing Hips

Letters to the EditorDuck Wing Hips J. Randunna Corea, MChOrth, FRCSE Orth, FRCS Khalid Al-Umran, and MD, CABP Madampath SankarankuttyMChOrth, FRCSG, FRCS J. Randunna Corea Department of Orthopedic Surgery, King Faisal University, P.O. Box 2114, Dammam 31451, Saudi Arabia Search for more papers by this author , Khalid Al-Umran Department of Pediatrics, King Faisal University, P.O. Box 2114, Dammam 31451, Saudi Arabia Search for more papers by this author , and Madampath Sankarankutty Department of Orthopedic Surgery, King Faisal University, P.O. Box 2114, Dammam 31451, Saudi Arabia Search for more papers by this author Published Online:1 Jul 1988https://doi.org/10.5144/0256-4947.1988.300SectionsPDF ToolsAdd to favoritesDownload citationTrack citations ShareShare onFacebookTwitterLinked InRedditEmail AboutIntroductionWe wish to highlight a physiologic postural variant of the hip joints in neonates, graphically termed "duck wing hips." Though familiar to personnel dealing with neonates, we have seen treatment instituted on two occasions by strapping and once by traction. The objective of this letter is to prevent unnecessary and potentially harmful treatment in a situation that resolves spontaneously.In infants with duck wing hips, the lower limbs are abducted at the hips and lie flat on the cot. The hips are flexed 120° or more, and the knees to similar degree (Figure 1). The hips are stable. Abduction of the hips can be passively corrected, but the thighs cannot be fully extended.Figure 1. Duck wing hips.Download FigureA prospective study of 25 consecutive neonates with duck wing hips was made. Eighteen were Saudi nationals. Twenty infants were premature. Their period of gestation ranged from 27 to 37 weeks with a mean of 33.4 weeks. Their birth weight ranged from 1280 to 2200 g with a mean of 1790 g. Five were full term with a mean birth weight of 3100 g. Twenty-four of the 25 neonates were hypotonic at birth. An x-ray film of one of these infants in utero showed the usual fetal position with flexed, nonabducted hips in the neutral position and flexed knees. All 25 infants regained normal muscle tone and full range of movement of the hips after 4 to 6 weeks. Follow-up at 1 year showed the hips to be stable with a full range of movement.Duck wing hips are a physiologic postural variant of neonates seen more commonly in prematures and associated with hypotonia. They are not due to posture in utero. The condition is easily distinguished from congenital abduction contracture of the hip, which is usually unilateral and accompanied by pelvic tilt and spinal lordosis.1 The duck wing posture resolves spontaneously, and unnecessary treatment by strapping, traction, or manipulation could exert abnormal pressures on the femoral head and induce the risk of avascular necrosis.2ARTICLE REFERENCES:1. Sharrard WJW. Congenital abduction contracture of the hip. In: Paediatric orthopaedics and fractures, vol 1. 2nd ed. London: Blackwell Scientific Publications, 1979:382. Google Scholar2. Bradley J, Wetherill M, Benson MK. "Splintage for congenital dislocation of the hip: is it safe and reliable?" J Bone Joint Surg Br. 1987; 69(2):275–63. Google Scholar Previous article FiguresReferencesRelatedDetails Volume 8, Issue 4July 1988 Metrics History Published online1 July 1988 InformationCopyright © 1988, Annals of Saudi MedicinePDF download