Movements of the human shoulder represent the result of a complex dynamic interplay of structural bony anatomy and biomechanics, static ligamentous and tendinous restraints, and dynamic muscle forces. The complexity of the ankle anatomy has a significant influence on the biomechanical performance of the joint, and this paper discusses the motions of the ankle joint complex, and the joints at which it is proposed they occur. Scapulothoracic st joint known as a functional joint. During the concentric phase in a very wide stance pushup, the joint action is shoulder horizontal adduction. As the major joint in the shoulder complex, the glenohumeral joint permits the. The best sleeping position for back pain, neck pain, and sciatica tips from a physical therapist duration. Apr 27, 2018 this study aimed to develop a subjectspecific musculoskeletal modeling framework to quantify the influence of a powered robotic assistive exoskeleton on shoulder muscle and joint function during movements with and without gravity compensation. There are interactive popup questions throughout this lecture. If the glenohumeral joint was a pure ballandsocket joint, the joint icr would be coincident with the two elementary rotations. Previous studies have given a thorough insight into the biomechanics of the shoulder joint after rsa including joint forces and deltoid function, transfer procedures and strategies to avoid inferior impingement15, 16. The shoulder complex mechanics, muscle function and exercise marilyn m. The muscles surrounding the joint undergo reflex spasm in response to pain originating in the joint, which in turn serves to immobilize the joint and thus reduce the pain.
You can also consider the contributions of the upper thoracic, costal and sternomanubrial joints when. Pdf kinematics and biomechanics of reverse shoulder arthroplasty. This can cause poor performance, and can cause or exacerbate shoulder injury. Shoulder biomechanics lecture originally developed by bryan morrison, ph. A biomechanical model of the scapulothoracic joint to. Which muscle is a powerful defense to the front of the shoulder joint, preventing displacement of the head of the humerus.
Shoulder anatomy biomechanics pathomechanics youtube. Combined or isolated injury to vital osseous and soft tissue structures of the elbow joint a. Zuckerman orthopaedic surgery, nyu hospital for joint diseases, new york. Associate professor of education, university of north texas the shoulder joint consists primarily of the glenoid fossa of the scapula and humeral head. Helps to stabilize the shoulder joint by keeping the head of the humerus firmly pressed medially against the glenoid fossa of the scapula 16. For tendon, the fiber force response is exponential, and the shear modulii are 100 times. The shoulder complex mechanics, muscle function and exercise. It is a ball and socket modified ovoid joint and it is the most mobile joint in the body. The biomechanics of the shoulder joint has been an active area of study for many years. These scapu lar muscles dynamically position the glenoid so that efficient glenohu. Scapular joint position sense at different arm elevation angles. Its base is attached to the m ar gin of the glenoid fossa by fibrocartilage and fibrous bone. The model is designed specifically for estimating muscle and jointreaction. The humerus is a long bone that forms the articulations of the glenohumeral joint proximally with the scapula, and the humeral ulnar joint and humeral radial joint.
Biomechanics of the shoulder complex look at how the entire shoulder complex moves and start to get a feel for where the restrictions are and where they compensate. Unraveling the biomechanics of shoulder reconstruction. Injury to the shoulder joint is followed by pain, limitation of movement, and. Reverse shoulder arthroplasty leads to significant. At the root of shoulder instability is its structure. Jun 14, 2018 shoulder joint is a ball and socket joint also known as glenohumeral joint. Biomechanics and in particular biomechanics of the human shoulder involves research. These changes may affect the biomechanics of the shoulder and alter the shoulder joint inducing loss of power and pain according to the underlaying pathology. For example, when the arm is abducted, the greater tubercle of the. This does mean however, that the bony surfaces of the joint itself and those surrounding the joint play a key role in injuries of the shoulder. Sghl su p erio r g le n o h u m e ra l lig a m e n t, m g h l m id d le g le n o h u m e ra l lig am en t. The joint is sensitive to pain, pressure, excessive traction, and distension. This chapter concentrates on the physiological range of motion and the different stabilizing and anatomical aspects of the shoulder.
It is important to recognize the unique anatomy of the elbow, including the bony geometry, articulation, and soft tissue structures. Injury to 1 or more of these components through overuse or acute trauma disrupts this complex interrelationship and places the shoulder at increased risk. The wrist and hand complex joint structure and function. Know its structure, function, movements, muscles, tendons. Biomechanics of the shoulder joint jama surgery jama. Biomechanics of the shoulder complex free download as powerpoint presentation. Normal anatomy and biomechanics of the knee fred flandry, md, facsw and gabriel hommel, md abstract. The complexity of shoulder mechanics combined with the movement of skin relative to the scapula makes it difficult to measure shoulder kinematics with sufficient accuracy to distinguish between symptomatic and asymptomatic individuals. In the field of biomechanics, joint limits have often been measured, using various mechanical. Shoulder function is the result of the complex interplay of the osseous, ligamentar, capsular and muscular structures of the shoulder girdle. At 60 of abduction, the downward short rotator force was maximal at 9. Each joint proximal to the wrist complex serves to broaden the placement of the hand in space and to increase the degrees of. In normal upperquarter function, the scapula provides a stable base from which glenohumeral mobility occurs.
Dec 15, 2017 muscle function in glenohumeral joint stability during lifting task article pdf available in plos one 1212. Apr 23, 2020 as mentioned, the glenohumeral joint has great mobility. The primary function of the shoulder girdle is to give strength and range of motion to the arm. It helps position the hand in space, thus allowing the hand to perform activities of daily living.
Biomechanical relationships within the shoulder joint. Anatomy and function of the shoulder the shoulder is a ballandsocket joint and has the greatest range of motion of any joint in the body. The principal function of the sijs is to act as stress relievers, ensuring that the pelvic girdle is not a solid ring of bone that could easily crack under the stresses to which it is subjected adams et al. The glenohumeral joint is the most mobile joint in the. Abduction of the arm about the glenohumeral joint is accompanied by. Relationships between the humerus and scapula are particularly apparent in successful gymnastics performance.
Understand the biomechanics of the shoulder complex. Anatomy and function of the shoulder joint youtube. The biomechanics of the elbow joint can be divided into kinematics, stabilizing structures in elbow stability, and force transmission through the elbow joint. Dont wait until later to see if your treatment affected the. Biomechanics of hip joint 345 figure 2 a pelvic anatomical frame defined as fo llows. Varus stress is checked in extension equally by the joint articulation 55% and the soft tissue, lateral collateral ligament, and capsule. Ac joint plane synovial joint 3 rotational and 3 translational degrees of freedom the primary function of the ac joint is to allow the scapula additional range of rotation on the thorax and allow for adjustments of the scapula outside the initial plane of the scapula in order to follow the changing shape of the thorax as arm movement occurs. Shoulder complex anatomy osseous elements the shoulder complex includes the articulations of the humerus, the clavicle, the scapula, and the posterior surface of the ribs. While quantifiable differences do exist in proper mechanics for various sports, certain similarities are found in all overhand throws.
Biomechanics of the shoulder in this section, we explain shoulder biomechanics focusing on the rotator cuff muscles, and describe the concept of rotator cuff repair in the next section. Shoulder girdle permits largest rom of any complex in the body shoulder girdle increases rom with less compromise of stability scapulohumeral rhythm 4 joints vs. Glenohumeral joint anatomy, stabilizer, and biomechanics. Review specific functional anatomy of the shoulder complex.
This lack of awareness often translates into incomplete evaluation and diagnosis of shoulder problems. Review anatomy of shoulder complex and its function. However, so far it remains unclear why functional deficits in internalexternal rotation can occur, even though the muscles. The joint is formed by three skeletal bones and supported by several ligament and muscles. It discusses bones, ligaments, muscles and other structures that make up the shoulder joint.
In addition, scapular rehabilitation is often ignored. If you choose to pause the lecture and return at a later time, a natural break time would be after answering the interactive questions. Identify sources of pain not all anatomical illustrations are completely accurate. Motion and muscular function after reverse shoulder arthroplasty 73. Mu s c l e s a n d j o i n t ac ti o n s o f th e p u s h up. The shoulder s ability for multiple degrees of motion is based on the interaction of multiple structures that react to mechanical stimuli and adjust accordingly. Omar soliman basic orthopedics science course 2015. The application of biomechanics to the musculoskeletal system has led to a better understanding of both joint function and dysfunction, resulting in design improvements in devices such as joint arthroplasty systems and orthotic devices. The muscles that work concentrically on a joint are the same muscles working eccentrically on that joint. For specific identification of neural elements we made use of a special silver impregnation technique, described by novotny, for. Analyze overall mechanical effects on shoulder during movement.
Functional anatomy of the shoulder complex 25%30% of the humerus contacts the glenoid. Box 850, hershey, pa 170330850, usa a sound understanding of elbow anatomy and. Anatomy and biomechanics of the pelvis clinical gate. Only sc joint connects the components of shoulder joint to the axial skeleton. In a very narrow stance pushup, the joint action is shoulder flexion. Bio mechanics of the shoulder shoulder anatomical terms. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
The two main bones of the shoulder are the humerus and the scapula shoulder blade. The shoulder girdle includes three bonesthe scapula, clavicle and humerus. Observations on the function of the shoulder joint. Functionally, the knee comprises 2 articulationsthe patellofemoral and tibiofemoral. The elbow must be robust enough to allow it to function as a weightbearing joint, and therefore complex joint biomechanics are required to maintain its. Proper throwing mechanics may enable an athlete to achieve maximum performance with minimum chance of injury. But it is not, and the humeral head rotates around the joint icr. One essential property is the utilisation of a kinetic chain to generate and transfer energy from the larger body parts to the smaller, more injury. Pronation of the subtalar joint in a closed kinetic chain is calcaneal eversion with adduction and plantarflexion of the talus fig. Bio mechanics of the shoulder free download as powerpoint presentation.
Muscles were assumed exponential hyperelastic, incompressiblew. The tissue was stained following the haematoxylineosin and van giesson techniques. Current concepts the role of the scapula in athletic. The long head participates in extension and adduction of the glenohumeral joint, whereas the main function of the whole muscle is extension of the elbow joint. The elbow links the shoulder and the hand, and functions as a fulcrum for the forearm lever. The role of the scapula in athletic shoulder function w.
Sc joint is a plane synovial joint, with 3 rotatory and 3 translatory degrees of freedom. Biomechanics of the shoulder joint jama surgery jama network. Stability functions of shoulder girdle provides stable base from which shoulder muscles can generate force shoulder girdle muscles as stabilizers maintain appropriate forcelength relationship maintain maximum congruence of shoulder joint. However, most all shoulder kinematics studies model the glenohumeral joint as a ballandsocket joint to negate these differences.
Stability of the joint is governed by a combination of static ligaments, dynamic muscular forces, meniscocapsular aponeurosis, bony topography, and joint load. Which of the following parameters is used to assess muscle function using an isokinetic dynamometer. Functional anatomy of the shoulder pubmed central pmc. Sesh 3 is the shape parameter of the curvature of the exponential slope, and. Please read the section on basic shoulder anatomy before reading this section.
This paper provides an introduction to the biomechanics of the ankle, introducing the bony anatomy involved in motion of the foot and ankle. Kim 68 3dof, exponential redundancy resolution in 10 8m, 2f. Sternoclavicular joint movement of the clavicle at the sc joint inevitably produces movement of the scapula under conditions of normal function, because the scapula is attached to the lateral end of the clavicle. It is parametrized by l 0, the rate at which the event occurs. Stability at the scapulothora cic joint is dependent upon the sur rounding musculature.
Because of this mobility, it is at risk for injury or degenerative problems. Biomechanics of the shoulder complex shoulder anatomical. Cynthia norkin biomechanics pdf free download cynthia c norkin biomechanics pdf download cynthia norkin biomechanics pdf cynthia norkin biomechanics second edition pdf cynthia norkin bio mechanics book by cynthia norkin joint structure and function by cynthia norkin joint structure and function cynthia norkin pdf joint structure and function by cynthia norkin pdf cynthia norkins biomechanics. Shoulder joint or glenohumeral jointstructure, function. Pdf a survey of human shoulder functional kinematic. Feb 14, 2020 study identify these deltoid muscle images and explain briefly about them flashcards flashcards at proprofs front of card is a picture of the muscle and the back of card lists the muscles name, insertion, origin and action. Introduction shoulder joint gh joint has more mobility than stability. Forces in the shoulder joint tu delft repositories. Hershey medical center, h089, 500 university drive, p. The shoulder is an important functional joint, and its large range of motion rom poses. Automatic determination of shoulder joint limits using quaternion.
Research from jama surgery biomechanics of the shoulder joint. Additionally, basic musculoskeletal biomechanics concepts are important for clinicians. It is important to reevaluate functional mechanics before and after each treatment intervention. A n a t o m y a n d b io m e c h a n ic s o f t h e s h o u l d e r 161 f ig u re 2. Stability of the scapulothoracic joint depends on coordinated activity of the surrounding musculature. Anatomy and biomechanics of the elbow hand therapy hub. Biomechanics of overhand throwing with implications for. Mark frankle scott marberry derek pupello editors biomechanics. Joint function mechanical forces acting on connective tissue tension forces compression forces shear forces torque forces properties of connective tissue muscle ligaments facet joints intervertebral discs models of spine function t his chapter provides an academic picture of the applied anatomy and biomechanics of the musculoskeletal system. Specifically, the muscles of the scapula function as follows. Pdf muscle function in glenohumeral joint stability during. Mar 24, 2019 the shoulder is not a single joint, but a complex arrangement of bones, ligaments, muscles, and tendons that is better called the shoulder girdle. The top of the humerus is shaped like a ball and it sits in a socket on the end of the scapula.
In order to better understand the biomechanics of the shoulder it is important to understand its anatomy. The shoulder joint is structurally classified as a synovial ball and socket joint and functionally as a diarthrosis and multiaxial joint. To make the subject at once comprehensive and relevant to the clinician, the structure and function of the sternoclavicular and acromioclavicular joints are dealt with first. Biomechanics and pathomechanics of the shoulder joint with. The shoulder joint is a shallow ballandsocket joint that is formed by the attachment of the head of the humerus with the glenoid fossa of the scapula. Biomechanical relationships within the shoulder joint by william cornelius, ph. Finite element models of the human shoulder complex. The rotator cuff muscles work not only as a motion actuator abduction or external and internal rotations but also as a shoulder stabilizer. The extremely large range of motion of the upper arm is made possible by the coordinated interaction of multiple joints, and the biomechanics of the glenohumeral joint can be studied and understood only in relation to the biomechanics of the shoulder as a whole. Oct 16, 2016 introduction the shoulder is composed of 3 synovial joints. Finite element analysis of reverse shoulder joint prosthesis. The first role of the scapula is to be a stable part of the. A thorough understanding of the functional anatomy of the shoulder provides the clinician with a foundation for caring for athletes with shoulder injuries. Multibody skeletal models can improve motion capture accuracy by reducing the space of possible joint movements, and models are used widely to improve.
Musculoskeletal model of the human shoulder for joint force. In extension, the anterior capsule provides about 70% of the soft tissue restraint to distraction, whereas the medial collateral ligament assumes this function at 90 degrees of flexion. Because of its component parts, a description of the biomechanics of the shoulder complex is rather involved. Assessment of a functional pulling task in older adults with and without a. The failure of the scapula to perform these roles causes inefficient physiology and biomechanics and, therefore, inefficient shoulder function. Effects of stretching and strengthening exercises, with and. Roche and others published kinematics and biomechanics of. The scapula extends up and around the shoulder joint at the rear to form a roof called the acromion, and around the shoulder joint at the front to form the coracoid process. This puts greater demands on the muscles for securing the shoulder girdle. Armstrong, bscpt, md, msc, frcsc department of orthopaedics and rehabilitation, penn state college of medicine, penn state milton s. Finite element analysis of reverse shoulder joint prosthesis siavash emami submitted to the institute of graduate studies and research in partial fulfillment of the requirements for the degree of master of science in mechanical engineering eastern mediterranean university july 20 gazimagusa, north cyprus. However, most all shoulder kinematics studies model the glenohumeral joint as a ballandsocket joint. Loss of elbow function can severely affect activities of daily living.
Recent research, however, has demonstrated a pivotal role for the scapula in shoulder function, shoulder injury, and shoulder. The joint capsules and the glenohumeral ligaments of 12 human shoulder specimens were histologically investigated by light microscopy. Sc joint connects the components of shoulder joint to the axial skeleton. Measuring the dynamic in vivo shoulder kinematics is crucial to better understand numerous pathologies, but remains a challenging problem due to its complicated anatomy, large range of motion and fast.
Lagrange function of a mechanism augmented by constraints. Basic shoulder biomechanics there are three joints in the shoulder complex. Modulation of shoulder muscle and joint function using a. Contributions of the deltoid and rotator cuff to shoulder. Biomechanics of the shoulder and elbow sciencedirect. Identify these deltoid muscle images and explain briefly. Deltoid force was maximal with the arm abducted 90, and was calculated to be 8.