Muscle Slings Research Articles

Twisted orientation of the muscle bundles in the levator ani functional parts in women: Implications for pelvic floor support mechanism.

This study presents a comprehensive investigation of the anatomical features of the levator ani muscle. The levator ani is a critical component of the pelvic floor; however, its intricate anatomy and functionality are poorly understood. Understanding the precise anatomy of the levator ani is crucial for the accurate diagnosis and effective treatment of pelvic floor disorders. Previous studies have been limited by the lack of comprehensive three-dimensional analyses; to overcome this limitation, we analysed the levator ani muscle using a novel 3D digitised muscle-mapping approach based on layer-by-layer dissection. From this examination, we determined that the levator ani consists of overlapping muscle bundles with varying orientations, particularly in the anteroinferior portion. Our findings revealed distinct muscle bundles directly attached to the rectum (LA-re) and twisted muscle slings surrounding the anterior (LA-a) and posterior (LA-p) aspects of the rectum, which are considered functional parts of the levator ani. These results suggest that these specific muscle bundles of the levator ani are primarily responsible for functional performance. The levator ani plays a crucial role in rectal elevation, lifting the centre of the perineum and narrowing the levator hiatus. The comprehensive anatomical information provided by our study will enhance diagnosis accuracy and facilitate the development of targeted treatment strategies for pelvic floor disorders in clinical practice.

Single-Stage Augmentation Mastopexy With Composite Reverse Inferior Muscle Sling Technique for Autologous Reinforcement of the Inferior Pole: Technical Refinements and Outcomes.

Single-stage augmentation mastopexy (SAM) is a common procedure, but revision rates are high. Muscle slings have been used in SAM, but despite satisfactory outcomes, most studies do not include objective or accurate measurements of implant/breast position. This article describes a surgical technique for SAM employing a composite reverse inferior muscle sling (CRIMS). The authors sought to assess outcomes from primary SAM procedures utilizing the CRIMS technique in a cohort of patients operated on by a single surgeon. Thirty-two patients (60 breasts) aged a mean of 43.1 ± 6.8 years underwent primary CRIMS mastopexy to treat severe ptosis (grade III-IV) in 25 patients (78.1%). The average implant volume was 255 cc (range, 215-335 cc). Three-dimensional imaging obtained from the Divina scanner system was employed to evaluate lower pole stretch and lower pole arc and to determine long-term ptosis. Four cases of complications were observed in 3 patients (9.3%), minor dehiscence in 2 and capsular contraction in 1, during a mean follow-up of 42 months. The value for lower pole stretch was 5.5% (P < 0.0001) between 10 days and 1 year, with the majority occurring early in the first 6 months, indicating that lower pole arc remained steady during the last months of follow-up. Advances in techniques have led to improvements in aesthetic outcomes following SAM, and CRIMS can play a helpful role. Our results show this procedure is suitable for patients with breast ptosis, with acceptable complication rates and the added bonus of implant stabilization within the pocket.

Three muscle slings of the pelvic floor in women: an anatomic study

The region anterior to the anal canal in women is composed of intertwined smooth and skeletal muscles. The present study aimed to clarify skeletal muscle morphology in the anterior region of the anal canal. The pelvic floor muscles of 28 pelvic halves from 16 female cadavers (mean age 79.75 years) were dissected from the inferior aspect to examine the perineal muscles, followed by midline transection and dissection from the inner surface to examine the pelvic outlet muscles. The bulbospongiosus muscle was found to be attached to the lateral surface of the external anal sphincter. The superficial transverse perineal muscle crossed superiorly to the bulbospongiosus and coursed medially toward its contralateral muscle bundle deep to the anterior portion of the external anal sphincter. The superficial transverse perineal muscle formed the middle sling. From the medial aspect, the anterior part of the levator ani was divided into anterior and posterior bundles to form the anterior and posterior slings, respectively. This study proposes that three muscular slings could be important in supporting the pelvic floor in women. In addition, this study shows that the anterior skeletal muscular wall of the anal canal is composed of the anterior muscle bundle of the levator ani, superficial transverse perineal, and proper external anal sphincter muscles.

FMS: Relationship between muscul activity in deep squat ans trunk stability pushup

Aims and Objectives:Motor control is described as the internal control and regulation processes which facilitate movements. Scientists divide motor control into the function of stability and the movement to maintain balance in locomotion. The FMS is used to analyze the motor behavior of muscle slings on the one hand, and to estimate injury risk on the other hand. Yet, the true extent of the FMS’ diagnostic information remains unclear. The low intensity level of the FMS items causes low tension within the motor network. Based on Hennemen’s size principle, this is a clear indicator for the activation of slow-twitch fibers in the muscle. A possible relationship between movement and stability function of muscle slings has yet to be examined. Therefore, the aim of this investigation was to shed light on the motor behavior of dynamic and isometric muscle activity as well as the examination of average muscle activity when performing the items deep squat (DS) and trunk stability pushup (TSPU).Materials and Methods:Data from 16 collegiate athletes (22.1±1.5yrs) with various sports histories was analyzed. The data analysis was based on Kendall’s tau correlation coefficient. The items DS and TSPU were rated via an ordinal ranking system ranging from 0 (pain) to 3 (adequate). Muscle activity was recorded with a new EMG device at a rate of 25 Hz (Myontec Ltd, Kuopio, Finland). In a concurrent pilot study the reliability of this device was examined with a progressive loaded squat protocol (50 up to 125% BW). It indicated almost perfect reliability for the quad/ham balance, quadriceps distribution (r< 0.9, CV:3-5%) and high reliability for the hamstrings (r >0.8, CV:<10%).Results:Strong relationships between the quad/ham balance (r=0.7, p<0.01) and quadriceps distribution (r=0.6, p<0.03) in DS and TSPU were identified. The connection between hamstring muscle activity balance was low (r< 0.2, p>0.5). In both items, the muscle contractions were dominated by the activation of the quadriceps (79% vs. 21% hamstrings). Additionally, the average muscle activity was 4 times higher in a loaded squat (100% BW) than it was in DS. Generally, DS was rated as follows: score 3 (3 times) and score 2 (13 times). For the item TSPU score 3 was given 14 times and score 2 was given 2 times.Conclusion:The relationship between dynamic and static motor behavior of the quadriceps supports the connection between the stabilizing and movement function of muscle slings. The low intensity corresponds with the slow EMG activity in DS, which is an indicator for the activation of mainly slow twitch muscle fibers. This scientific innovation is relevant for practitioners as it establishes the diagnostic value of the FMS. Based on this evidence, the FMS provides information with regards to low tension motor behavior. It is unlikely that this information is specific enough to estimate injury risk or performance because when it comes to return to sport decisions, it is also important to obtain information of motor control associated with fast-twitch fibers.

Effect of lumbopelvic myofascial force transmission on glenohumeral kinematics – A myo-fascia-biomechanical hypothesis

Abstract Introduction The clinical management of shoulder disorders do not commonly includes the myo-fascial–skeletal contributions from the lumbopelvic (LP) region. Nevertheless, a notable myofascial–biomechanical connection exists between LP and shoulder regions. Aim The current paper proposes a quantifiable medical hypothesis that there will be an increased anterior humeral head translation (ATHH) in the glenohumeral joint (GHJ) due to altered myofascial force transmission that results from LP dysfunction. Material and methods A literature search was conducted in Science Direct and PubMed databases for articles published from January 1990 to December 2015. Medical Subject Headings and other keywords for search were myofascial continuity, force transmission, muscle slings, lumbopelvic-glenohumeral joint and biomechanics. Results and discussion The hypothesis suggests a clinical reasoning that impaired myofascial force transmission from LP region as one of the contributing factors for shoulder pathogenesis. The hypothesis is proposed based on the anatomical and biomechanical relationship between the LP region and the contralateral GHJ. Evidences of myofascial continuity between the LP and GHJ, myofascial force transmission and integrated energy transfer theory are explained to strengthen the proposed hypothesis. An experimental method to test the proposed hypothesis is recommended for researchers and clinicians. A theoretical understanding of the pre stressed spring system via the myofascial chains is applied to strengthen the reasoning on the current hypothetical connection between LP and contralateral GHJ. Conclusions The implication of the new medical hypothesis may substantiate the understanding of the clinicians on the connections between the LP and the contralateral GHJ to consider a global myo-fascial–skeletal management of shoulder disorders.

Pathologic anatomy of the soft palate, part 1: Embryology, the hard tissue platform, and evolution

The purpose of this communication is to explore in detail the developmental anatomy of the soft palate, its pathologies, and strategies for management. Despite the voluminous literature regarding complete cleft palate in its usual presentation, little attention has been paid to the biology of the isolated soft palate cleft. It exists as a spectrum, ranging in severity from the submucous variant, with nothing notable save a groove and a palpable defect of the posterior spine, all the way to a complete disruption of the soft tissue envelope and the horizontal palatine shelves. All these presentations are but variations of common pathology. Much can be gained from a disciplined examination of these. Our discussion includes two parts. The first part is on the embryologic events that generate the mesenchymal building blocks from which the posterior palate is constructed: palatine bone, oral and nasal mucosa, palatine aponeurosis, and muscle slings. Palate structures develop from neural crest and mesoderm; these tissues originate at specific sites along the axis of the embryo and they can be mapped according to the developmental units of the central nervous system (CNS) from which they are innervated. These units, called neuromeres, are specific zones within the neural tube, the boundaries of which are established by the expression pattern of homeotic genes. The forebrain (prosencephalon) has telencephalon and 3 prosomeres, the midbrain (mesencephalon) has 1-2 mesomeres, and the hindbrain (rhombencephalon) has 12 rhombomeres. Each neuromere has a specific neuroanatomic content and is hardwired to specific tissues outside the brain. We next consider a model of the palate which is analogous to a pinball machine that consists of a platform (bone) and mobile “flippers” or lever arms (the velum). In this study, the osseous platform is discussed in detail with neural crest bones being coded by the sensory innervation of their surrounding soft-tissue envelope. Maxilla, palatine bone, and vomers are all derivatives of hindbrain neural crest arising from rhombomere 2 but distributed according to various neurovascular pedicles of the V2 stapedial system, the anatomy of which will be explained in detail. Next, the evolution of palate will be presented as a series of innovations favoring increased metabolic capacity. A final appendix presents a functional classification of cranial nerves which I have endeavored to make straightforward. This will prove useful when reading the second part of this manuscript having to do with the neuromuscular apparatus of the soft palate.

Myofascial force transmission in sacroiliac joint dysfunction increases anterior translation of humeral head in contralateral glenohumeral joint

Abstract Introduction Posterior and anterior oblique muscle slings contribute to the force closure mechanisms that provide stability to sacroiliac joint. These global muscle slings consist of myofascial network of fascia, muscles and tendons from global muscles. It links the lumbopelvic region to other joints of musculoskeletal system especially the contralateral glenohumeral joint (GHJ). Any sacroiliac joint dysfunction (SJD) may likely disrupt the force transmission across the oblique slings and it can affect the contralateral GHJ. Aim The current study aims to investigate the effects of SJD on the contralateral GHJ. Material and methods An experimental study is designed recruiting 20 participants with SJD and 20 healthy participants as matched controls to test the hypothesis that SJD may cause excessive anterior translation of humeral head (ATHH) in contralateral GHJ. Using real time ultrasonography, resting position of humeral head (RPHH), ATHH and posttranslation distance of humeral head (PDHH) are compared between the GHJs among participants with SJD and the matched controls. Paired sample t-test and independent sample t-test are used to analyze the data. Results and discussion The paired sample t-test result showed statistically significant increase in ATHH (P = 0.03) and PDHH (P = 0.01) in contralateral GHJs among participants with SJD. The independent sample t-test showed a significant increase in RPHH (P = 0.01) and PDHH (P = 0.01) in SJD participants when compared to matched controls. Conclusion SJD contributes to excessive ATHH in the contralateral GHJ. This may occur due to altered myofascial force transmission across oblique sling muscles.

Pathology of the Palatal Aponeurosis in Cleft Palate

The palatal aponeurosis is a controversial structure, both in terms of its anatomy and its function. This article points out a pathologic finding in the cleft palate condition that has not been previously described.By means of surgical dissections, this study demonstrates in detail that the palatal aponeurosis exists even in cleft palates, but it is disrupted, malpositioned, and folded in two layers.This dissection method has been performed on more than 150 patients with cleft of the hard and soft palate, with or without cleft of the lip and alveolus. At the time of operation, the children were between 6 and 8 months of age.It is possible to dissect the two layers of the palatal aponeurosis, to unfold the aponeurosis, and to form a tough tendinous plane.For a functional physiologic reconstruction of the cleft palate, it is necessary not only to reconstruct the levator veli palatini and palatopharyngeus muscle slings, but also to approximate and suture the fibers of the palatal aponeurosis to the corresponding fibers of the opposite side after unfolding them in a medio-dorso-cranial direction. In this manner, a continuous palatal aponeurosis can be created, which subsequently can serve as a transmitter of the muscle forces.

Pathology of the palatal aponeurosis in cleft palate.

The palatal aponeurosis is a controversial structure, both in terms of its anatomy and its function. This article points out a pathologic finding in the cleft palate condition that has not been previously described. By means of surgical dissections, this study demonstrates in detail that the palatal aponeurosis exists even in cleft palates, but it is disrupted, malpositioned, and folded in two layers. This dissection method has been performed on more than 150 patients with cleft of the hard and soft palate, with or without cleft of the lip and alveolus. At the time of operation, the children were between 6 and 8 months of age. It is possible to dissect the two layers of the palatal aponeurosis, to unfold the aponeurosis, and to form a tough tendinous plane. For a functional physiologic reconstruction of the cleft palate, it is necessary not only to reconstruct the levator veli palatini and palatopharyngeus muscle slings, but also to approximate and suture the fibers of the palatal aponeurosis to the corresponding fibers of the opposite side after unfolding them in a medio-dorso-cranial direction. In this manner, a continuous palatal aponeurosis can be created, which subsequently can serve as a transmitter of the muscle forces.

Femoral Head Excision Arthroplasty Using the Vascularised Rectus Femoris Muscle Sling

SummaryRectus femoris muscle slings were transposed over femoral head ostectomy sites in four large breed dogs, while in three other dogs, standard femoral head and neck excision arthroplasty was performed. After the operation two dogs, with rectus femoris muscle slings, showed transient swelling of the operated limb and remained weight bearing minimally throughout the 28-day study period. In the two remaining dogs with muscle transposition, the surgical sites were normal, but decreased weight bearing and marked lameness were apparent. The dogs with standard femoral head excisions did not have any postoperative problems with the surgical sites and were weight bearing, with slight to moderate gait abnormalities, after the operation. All of the dogs showed decreases in coxofemoral range of motion, standing hip angle and limb length of the operated leg but postoperative differences between the two treatment groups were not significant. Thigh muscle circumference was significantly less in dogs with rectus femoris muscle slings than those with standard femoral head excision. Extensive perfusion of transposed slings was apparent on angiographic studies. Histopathology of muscle slings showed focal inflammation, muscle fibre atrophy and fibrosis with intact neurovascular supply.Femoral head excisional arthroplasty was performed in seven large breed dogs, four of which had adjunctive rectus femoris muscle slings trans-posed over ostectomy sites. Although the rectus femoris muscle sling remained vascular and was associated with minimal immediate postoperative complications, dogs with muscle transposition showed decreased weight bearing, more obvious lameness and a slower return to function, than dogs with standard femoral head and neck excision. Dogs with rectus femoris muscle slings did not show any improvement in coxofemoral range of motion, standing hip angle or limb length, rather more thigh muscle atrophy was evident on day 28 after surgery.

Postoperative examination of the biceps femoris muscle sling used in excision of the femoral head and neck in dogs.

Twenty-four dogs underwent unilateral excision of the femoral head and neck. An adjunctive biceps femoris muscle sling procedure was done in 16 dogs. In eight dogs (controls), the flap was dissected and returned to its original position. Four dogs with muscle slings were euthanatized on days 2, 5, 30, and 60, respectively. Four control dogs were euthanatized on day 2 and four dogs on day 5. Limb function did not differ consistently between dogs with muscle slings and control dogs. There was marked swelling and edema of the affected limb in half the dogs with muscle slings but not in the controls. Postoperative temperature elevations were significantly higher in dogs with muscle slings on days 1 and 2 (p less than 0.05). Infection was documented in four dogs with muscle slings. Flaps from control dogs had only minor gross and histologic abnormalities. On days 2 and 5, flaps from dogs with muscle slings appeared congested and swollen beneath and distal to the ostectomy site, with infarction involving 50 to 90% of the muscle mass. On days 30 and 60, the muscle slings were atrophic and fibrous, and by day 60 a synovial membrane covered the surfaces of all slings within the pseudarthrosis. Muscle fiber loss was attributed to infarction, necrosis, and disuse atrophy.

Long-standing facial paralysis rehabiltation.

AbstractA group of 32 patients with severe facial paralysis from 2 to 30 years and of different etiologies were studied. Various degrees of nerve and muscle atrophy were noted in this group. A new concept relative to the status of the paralyzed face, its nerve and muscle system and their capacity for rehabilitation was acquired.The treatment of long‐standing paralysis has been relegated to fascial stripping, muscle slings, tarsorrhaphies and face‐lift operations. This investigation indicates that the situation is not totally irreversible. The determinant factors are the number of surviving axones and the viability of the facial muscles supplied by them. Regardless of the electrical testing, the facial nerve never totally disappears nor do the facial muscles. On surgical exploration, the facial nerve and the posterior belly of the digastric muscle were always recognizable in varying degrees of atrophy and fibrosis. A range of 20‐90 percent of normal size was noted.Electron microscopy of the nerve and muscles demonstrated axone degeneration still taking place and muscle fibers present in cases 20‐30 years post injury to the nerve. The degree of atrophy and fibrosis was dependent upon the length of the paralysis. It was also noted that the degree of severity was less as the site of injury became more peripheral. This was probably related to the rich extratemporal nerve interconnections from the sympathetics, cervical plexus, and cranial nerves V and IX. These findings verified the existence of a subliminal system which is non‐functional, but in certain instances had the potential for rehabilitation.Some of the most interesting aspects of facial rehabilitation in longstanding facial paralysis are beginning to unfold themselves in the recognized potential of a regrowth of axones in a depleted but not annihilated facial nerve system by nerve crossover and nerve grafting techniques. When the peripheral facial nerve system is absent, nerve implantation into the residual mimetic muscles or transposed masticatory muscles is indicated. The introduction of masticatory muscles into the face to accommodate this neural regrowth, when mimetic muscle potential remains subclinical, adds a new neuromuscular facility in the rehabilitation.

HABITUAL DISLOCATION OF THE SHOULDER JOINT

RECURRING dislocations of the shoulder joint have been recognized for centuries, Hippocrates being credited with the first description. Over the course of time treatment has been varied. The first recorded treatment consisted of plunging a hot iron into the axilla. There was little rationale in methods used until about 1882, when Cromer 1 advocated resection of the head of the humerus. In 1888 Albert 2 advised fusion of the shoulder. By 1903 recommendations had become much less radical. They fall into four groups or combinations thereof. From about 1903 attention was focused on the capsule, the treatment consisting chiefly of plication operations. By 1909 the style shifted to muscle slings. Ehrlich and Clairmont advocated taking a segment of the posterior deltoid, freeing it from its insertion into the humerus, stripping it free up to its origin and then slipping it through under the head of the humerus extracapsularly and attaching