Summary mans girdle s the general of his treeswinging ancestors, with of the posture, thorax has from anteriorposterior. The humeral head is a sphere in 90% of people, with an average radius of curvature in the coronal plane of 24 mm range 1928 mm. A total shoulder limitation motion, to slightly of humem i head if rotator with a prosthesis. Mark emphasizes the importance of understanding the mechanisms involved within the biomechanics of the shoulder. Biomechanical considerations of the normal and rotator. Athletes often incur injuries of the shoulder as they subject the joint to extreme ranges of motion and force, as well as excessive repetitions of these motions 2.
It has been suggested that the tendons of the rotator cuff muscles blend with the. Biomechanics of shoulder complex linkedin slideshare. The sphere of influence of the hand in space is highly dependent on shoulder and elbow motion. Kinematic analysis of the glenohumeral joint epublications. In mechanics, a couple is a system of forces that results in a moment without a resultant force and creates a. 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. Shoulder joint anatomy medvizz anatomy medical animations. Balancing mobility and stability, the biomechanics of the shoulder provides optimal use of the thumb and hand. This chapter concentrates on the physiological range of motion and the different stabilizing and anatomical aspects of the shoulder. Clinical anatomy and biomechanics of the glenohumeral joint. A force couple is defined as two equal but oppositely directed forces acting simultaneously on opposite sides of an axis that generates rotation.
The subscapularis muscle hello friends, this is the first of a fourpart series on the shoulder joint, focusing specifically on the rotator cuff and its biomechanical relationship with the deltoid muscle. This study aimed to evaluate the threedimensional kinematics of the shoulder joint in patients with shoulder impingement and normal volunteers with focus on three wellknown diagnostic tests. Biomechanics and assessment of the painful shoulder. Functionally, the knee comprises 2 articulationsthe patellofemoral and tibiofemoral. It is important to reevaluate functional mechanics before and after each treatment intervention. Feeley, md department of orthopaedic surgery, university of california at san francisco, san francisco, ca, usa reverse total shoulder arthroplasty is an effective procedure for treatment of glenohumeral joint. Armstrong, bscpt, md, msc, frcsc department of orthopaedics and rehabilitation, penn state college of medicine, penn state milton s.
Shoulder function is the result of the complex interplay of the osseous, ligamentar, capsular and muscular structures of the shoulder girdle. Bhanu prakash usmle, fmge and neet pg 83,901 views. This chapter addresses the anatomy and biomechanics, especially the recently acquired knowledge, pertaining to diagnoses and treatments frequently encountered by the shoulder surgeon. Introduction shoulder joint gh joint has more mobility than stability. Associate professor of education, university of north texas the shoulder joint consists primarily of the glenoid fossa of the scapula and humeral head. There is a fine balance between the mobility to perform athletic activities and stability required to power and stabilise the arm. Individuals with tos typically experience upper limb pain, numbness, tingling, or weakness that is exacerbated by shoulder or neck movement. Which muscle is a powerful defense to the front of the shoulderjoint, preventing displacement of the head of the humerus. In particular, contributions of sternoclavicular sc and ac joint motions to overall scapulothoracic st motion during arm elevation will be discussed. Mar 30, 2016 the shoulder consists of two force couples. Lennard funk the shoulder is potentially one of the most unstable joints of the body, with very little bony stability or containment and has been likened to a golf ball on a golf tee. Shoulder joint reaction force shoulder replacement 2 reversed shoulder replacement 4 9. The glenohumeral joint is what the layman and many in the healthcare field think of as the shoulder joint. Because of the multiple joints involved during shoulder movement, it is prudent.
Relationships between the humerus and scapula are particularly apparent in successful gymnastics performance. Review anatomy of shoulder complex and its function. Biomechanics of the shoulder complex shoulder anatomical. This puts greater demands on the muscles for securing the shoulder girdle. Identify abnormal biomechanics of the shoulder and how dysfunction disrupts function at varying stages of motion. Pdf biomechanical basis of common shoulder problems. Biomechanics of the shoulder since the time of leonardo di vincis pioneering exploration of the human anatomy, man has recognized the perfect union of form and function found in the shoulder joint. Jospt janlfeb 1985 biomechanics of the shoulder figure lb the right scapula. Analyze overall mechanical effects on shoulder during movement.
The shoulder complex has the greatest mo bility of all joints. 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. But it is not, and the humeral head rotates around the joint icr. Shoulder problems, glenohumeral joint, rotator cuff dysfunction. If the glenohumeral joint was a pure ballandsocket joint, the joint icr would be coincident with the two elementary rotations. The joints of the shoulder number from four to five, depending on interpretation. Normal anatomy and biomechanics of the knee fred flandry, md, facsw and gabriel hommel, md abstract. Relocation test instead of bringing arm back to neutral, put hand over shoulder to provide anterior support that they need and relocate it 3.
Biomechanics of the spine 142 biomechanics of spinal components i 142 biomechanics of spinal components ii 144. 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. Deltoid force was maximal with the arm abducted 90, and was calculated to be 8. In this article, we describe the basic knowledge about shoulder biomechanics, which is thought to be useful for shoulder surgeons to perform surgeries, and introduce our recent experiment data and latest biomechanics information. I got started years ago writing about biomechanics. Although this joint is considered a ball humerus and socket glenoid joint, the socket covers only onequarter of the humeral head. A thickening of m iddle layer reinforces the axillary pouch. Biomechanics of the shoulder girdle audio and pdf yoga. Only sc joint connects the components of shoulder joint to the axial skeleton. Box 850, hershey, pa 170330850, usa a sound understanding of elbow anatomy and. Bignardi department of mechanics, technical university of turin politecnico di torino, corso duca degli abruzzi 24 10129 torino italy abstract. Jospt march 1987 kinesiology of the shoulder table 3 muscle actions at the shoulder complex muscle biceps brachii long head may abduct the humerus if the humerus is externally rotated. Biomechanics of reverse total shoulder arthroplasty jonathan l. Helps to stabilize the shoulder joint by keeping the head of the humerus firmly pressed medially against the glenoid fossa of the scapula 16.
Compared to the shoulder, which has a large range of motion in all three axes of rotation, elbow range of motion is relatively constrained. Pdf balancing mobility and stability, the biomechanics of the shoulder provides. Knowledge of the biomechanics is therefore essential if one is to properly assess and treat shoulder pathology. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Biomechanics of the shoulder joint jama surgery jama network. The anatomies and biomechanics of the glenohumeral joint and the scapulothoracic articulation are the subjects of this article. 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. Jan 04, 2017 shoulder joint anatomy medvizz anatomy medical animations. This chapter concentrates on the physiological range of motion and the different stabilizing and anatomical aspects of.
Understand the normal biomechanics of the shoulder. Morrey, md, kainan an, phd because of its component parts, a description of the biomechanics of the shoulder complex is rather involved. Not all standard free weight exercises actually work the muscles they were designed to strengthen, and some can even be harmful. Chapter 6 biomechanics of the shoulder eiji itoi, md, phd, bernard f. The glenohumeral joint itself has to be positioned and stabilised in relation to the trunk by the scapulothoracic joint, which functions by suspension of the scapula from the. Clinical anatomy and biomechanics of the glenohumeral. Pdf a 3d biomechanical skeleton model for posture and. The axis around which movement takes chapter 2 joint anatomy and basic biomechanics figure 22 a, midsagittal plane. The glenohumeral joint motion is a result of a complex interplay between the passive and active stabilizers that require intricate balance and synchronicity. The latissimus dorsi, serratus anterior, pectoralis major, and del. To make the subject at once comprehensive and relevant to the clinician, the structure and function of the sternoclavicular and acromioclavicular.
In mechanics, a couple is a system of forces that results in a moment without a. Identify the correct motion within the plane of the scapula when assessing and treating the shoulder. Bio mechanics of the shoulder free download as powerpoint presentation. A 3d biomechanical skeleton model for posture and movement analysis article pdf available in studies in health technology and informatics 123. The effects of these pathological changes, and others, are predictable by consideration of natural joint anatomy and biomechanics of the joint. Glenohumeral ligaments static ligamentous restraints in different arm positions. Flexionextension the normal range of elbow motion in. The anatomy and biomechanics of the glenohumeral joint are then.
T he joints of the shoulder com plex have to rely on adjacent ligam ents and m uscles to provide stability. This paper was presented at the 1 st congress of asiapacific knee, arthroscopy and sports medicine society in april. These four tendons blend intimately together to form a continuous rotator cuff. Providing a fortuitous combination of mobility and stability, the shoulder joint complex permits a wide range of motion that differentiates human. Elbow biomechanics kinematics together with the shoulder, the elbow acts to position the hand in space. Shoulder biomechanics lecture originally developed by bryan morrison, ph. Currently, manual rom measurement of the gh joint in extensionflexion. However, most all shoulder kinematics studies model the glenohumeral joint as a ballandsocket joint to negate these differences. Dysfunction manual techniques for the shoulder manual techniques for the. Research from jama surgery biomechanics of the shoulder joint. Biomechanics of reverse total shoulder arthroplasty. Which muscle is a powerful defense to the front of the shoulder joint, preventing displacement of the head of the humerus. Stability of the joint is governed by a combination of static ligaments, dynamic muscular forces, meniscocapsular aponeurosis, bony topography, and joint load. Forces in the shoulder joint tu delft repositories.
The purpose of this manuscript is to identify recent advances in understanding of normal and abnormal biomechanics of the shoulder as related to rehabilitation of shoulder impingement. Glenohumeral joint anatomy, stabilizer, and biomechanics. The shoulder joint requires active stabilization from the rc muscles due to its nonconstrained nature and dislocating forces of the prime shoulder movers e. O n the other hand, the shoulder com plex is com posed of the scapulothoracic articulation and the glenohum eral joint to. Scapulothoracic muscles the stability of the glenohumeral joint is also affected by the large muscles acting away from the shoulder joint itself. Apprehension test lay on back, shoulder in 90 degree abduction, elbow is 90 degree flexion and put strain on anterior shoulder. The shoulder joint is unique, as multiplanar mobility of the joint is dominant over static stability. The rotator cuff muscles work not only as a motion actuator abduction or external and internal rotations but. Biomechanics of the shoulder and elbow sciencedirect. The shoulder, being the most mobile joint of the human body, is highly susceptible to injury 1.
Dec 28, 2015 normal shoulder joint biomechanics orthopaedic surgery department. Thoracic outlet syndrome tos describes a group of disorders that are due to a dynamic compression of blood vessels or nerves, between the clavicle and first rib or cervical vertebral nerve roots. At 60 of abduction, the downward short rotator force was maximal at 9. Hershey medical center, h089, 500 university drive, p. This generous amount of mobility can lead to a multitude of intrinsic ailments about the shoulder and, in fact, a majority of shoulder problems stem from this. 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. Shoulder instability biomechanics shoulderdoc by prof. Bio mechanics of the shoulder shoulder anatomical terms.
C ontrary to the anterior joint capsule, the posterior is quite thin. 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. Anatomy and biomechanics of the shoulder request pdf. Biomechanics of the shoulder complex free download as powerpoint presentation. With more than 37 years of clinical and research experience, mark albert delivers the most uptodate, evidencebased information on how to become proficient in your approach to the dysfunction of the shoulder. Shoulder biomechanics and exercises medbridge blog. The loosepacked positions allow for better joint lubrication, less frictional forces on the joint sur faces, and more freedom of movement through combined joint surface spin, roll, and slide. Apr 22, 2014 the glenohumeral joint is the articulation that primarily endows the shoulder with its huge range of movement, but this is achieved by trading off inherent stability. Because of its component parts, a description of the biomechanics of the shoulder complex is rather involved. Pdf balancing mobility and stability, the biomechanics of the shoulder provides optimal use of the thumb and hand. Biomechanical relationships within the shoulder joint.
133 539 785 663 878 412 996 573 502 23 114 1001 755 287 874 172 91 702 300 23 992 301 538 163 1115 1049 504 829 221 424 778 426 1355 1421