Articulação esternoclavicular Ir para: navegação, pesquisa

Description

The Sternoclavicular Joint (SC joint) is formed from the articulation of the medial aspect of the clavicle and the manubrium of the sternum.  It is one of four joints that compose the Shoulder Complex.  The SC joint is generally classified as a plane style synovial joint, and has a fibrocartilage joint disk.^[1]  The ligamentous reinforcements of this joint are very strong, often resulting a fracture of the clavicle before a dislocation of the SC Joint.^[2]

Anatomy

Joint Capsule

The SC Joint capsule is fairly strong but is dependent on the ligaments noted above for the majority of its support.

Joint Disk 

The SC Joint is surprisingly incongruent, and because of this incongruency a joint disk is present to enhance joint curvature and contact of the joint surfaces. Similar to meniscus of the knee, the SC Joint disk increases joint congruence and acts to absorb foces that may be transmitted along the clavicle. The disk is attached to the upper and posterior margin of the the clavicle, and to the cartilage of the first rib, which functions to help prevent medial displacement of the clavicle. This orientation divides the joint into seperate cavities. Greater movement occurs between the disk and the clavicle than between the disk and the manubrium. ^[3][4]

Ligaments 

LIGAMENT	DESCRIPTION	PROXIMAL ATTACHMENT	DISTAL ATTACHMENT	ROLE
Anterior Sternoclavicular Ligament [5][6]	Broad band of fibers, covering anterior surface of SC Joint running obliquely from Proximal Clavicle to Sternum in a downward and medial direction	Superior & Anterior Aspect Sternal End Clavicle	Anterior Superior Aspect of Manubrium	Reinforce Capsule Anteriorly Limits Anterior Translation of Clavicle Checks Anterior Movement of Head of Clavicle
Posterior Sternoclavicular Ligament [5][6]	Broad band of fibers, covering posterior surface of SC Joint Weaker than the Anterior Sternoclavicular Ligament.	Superior & Posterior Aspect Sternal End Clavicle	Posterior Superior Aspect of Manubrium	Reinforce Capsule Posteriorly Limits Posterior Translation of Clavicle Checks Posterior Movement of Head of Clavicle
Costoclavicular Ligament [5][6]	Anchors Inferior Surface of Sternal End of Clavicle to 1st Rib & its Costal Cartilage Orientation allows this ligament to act as the Primary Restraint for the SC Joint			Limits Elevation of Pectoral Girdle Acts as Fulcrum for Elevation-Depression Protration-Retraction Checks Clavicular Elevation and Superior Glide of Clavicle
Interclavicular Ligament [5][6]	Connects Sternal Ends of Each Clavicle with Capsular Ligaments and Upper Manubrium Produces a Bilateral Depression Force	Sternal End of One Clavicle	Sternal End of Other Clavicle	Strengthens Capsule Superiorly Resists Excessive Depression or Downward Glide of Clavicle

Muscles

There are no muscles that act directly on the SC Joint.  However, the SC Joint motions closely mimic the reciprical motions of the scapula.  In addition, the following muscles have an attachment of the clavicle and therefore may produce movement of the clavicle: 

Function

Motions Available & Range of Movement

The SC Joint has 3 Degress of Movement

Elevation and Depression  

During elevation, the clavicle rotates upward on the manubrium, and produces and inferior glide to maintain joint contact. The reverse actions happen when the clavicle is depressed. The motions are usually associated with elevation and depression of the scapula.^[7]

Elevation 0° – 45°		Depression 0° – 10°
Levator Scapulae	Dorsal Scapular Nerve C5 Cervical Nerves C3-C4	Pectoralis Minor	Medial Pectoral C8-T1
Trapezius – Upper	Spinal Accessory Motor CN XI Cervical Nerves C3-C4	Trapezius Lower	Spinal Accessory Motor CN XI Cervical Nerves C3-C4
Rhomboids	Dorsal Scapular Nerve C4-C5	Serratus Anterior – Inferior	Long Thoracic C5-C6-C7

Protraction and Retraction

During protraction, the concave surface of the medial clavicle moves on the convex sternum, producing an anterior glide of the clavicle, and an anterior rotation of the lateral clavicle. With retraction, the medial clavicle articulates with a flat surface and tilts or swings, causing an anterolateral gapping, and a posterior rotation at the lateral end. These movements are usually associated with abduction (protraction) and adduction (retraction) of the scapula, since the scapula is attached to the distal end of the clavicle.^[8][9]

Protraction 0° – 15° / 30°		Retraction 0° – 15° / 30°
Pectoralis Minor	Medial Pectoral C8-T1	Trapezius – Middle	Spinal Accessory Motor CN XI Cervical Nerves C3-C4
Serratus Anterior	Long Thoracic C5-C6-C7	Latissimus Dorsi	Thoracodorsal Nerve C6 – C8
		Rhomboids	Dorsal Scapular NerveC4-C5

Axial Rotation

When the arm is raised over the head by flexion the clavicle rotates passively as the scapula rotates. This is transmitted to the clavicle by the coracoclavicular ligaments

Rotation Elevating Glenoid Cavity 0° – 40° / 50°		Axial Rotation Depressing Glenoid Cavity 0° – 40° / 50°
Trapezius – Upper (Descending)	Suprascapular Nerve C5-6	Levator Scapulae	Dorsal Scapular Nerve C5 Cervical Nerves C3-C4
Trapezius – Lower	Axillary Nerve C5-6	Latissimus Dorsi	Thoracodorsal Nerve C6 – C8
Serratus Anterior – Inferior	Long Thoracic C5-C6-C7	Pectoralis Minor	Medial Pectoral C8-T1
		Rhomboids	Dorsal Scapular Nerve C4-C5

Closed Packed Position

• Maximum Shoulder Elevation

Open Packed Position

Pathology / Injury

The Sternoclavicular Joint is vulnerable to the same disease processes as other synovial joints, the most common of which are instability from injury, osteoarthritis, infection and rheumatoid disease. Patients may also present with other conditions, which are unique to the joint, or are manifestations of a systemic disease process.The most common clinical presentation is pain and swelling in the area of the Sternoclavicular Joint, either after an injury to the shoulder, or insidiously, with no history of trauma.^[10] A Sternoclavicular Joint sprain is a relatively rare sporting injury, which can range from a small sprain resulting in minimal pain and allowing ongoing activity, to a severe sprain resulting in significant pain, deformity and disability,^[11]

Techniques

Treatment

A mild sprain usually gets better by resting the joint for two to three days. Ice packs can be placed on the sore joint for up to 15 minutes at a time during the first few days after the injury.Moderate sprains may require some help to get the joint back into position. Your Physical Therapist at Humpal Physical Therapy & Sports Medicine Centers may recommend a figure-eight strap wraps around both shoulders to support the SC joint. Patients with a moderate sprain may need to wear this type of strap for four to six weeks. The strap protects the joint from another injury and lets the injured ligaments heal and become strong again.

Osteoarthritis of the SC Joint usually responds to initial rest, ice, and anti-inflammatory medications with Physiotherapy treatments which include range-of-motion exercises as pain eases, followed by a program of strengthening. If the symptoms of osteoarthritis do not respond to basic treatment over six to 12 months, Physiotherapy may refer you for surgical evaluation.

For post surgical treatment your surgeon may have you wear a sling to support and protect the shoulder for a few days. Then your physiotherapy can begin a rehabilitation program. First few physiotherapy treatments will focus on controlling the pain and swelling from surgery, followed with with range-of-motion exercises and gradually work into active stretching and strengthening with progressive loading of the shoulder. ^[12]

Resources References

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1. ↑ Levangie, P.K. and Norkin, C.C. (2005). Joint structure and function: A comprehensive analysis (4th ed.). Philadelphia: The F.A. Davis Company.
2. ↑ Allman, F.L. (1967). Fractures and ligamentous injuries of the clavicle and its articulation. J Bone Joint Surg. 49A:774-784.
3. ↑ Dutton, M. (2008). Orthopaedic: Examination, evaluation, and intervention (2nd ed.). New York: The McGraw-Hill Companies, Inc.
4. ↑ Levangie, P.K. and Norkin, C.C. (2005). Joint structure and function: A comprehensive analysis (4th ed.). Philadelphia: The F.A. Davis Company.
5. ↑ ^5.05.15.25.3 Dutton, M. (2008). Orthopaedic: Examination, evaluation, and intervention (2nd ed.). New York: The McGraw-Hill Companies, Inc.
6. ↑ ^6.06.16.26.3 Levangie, P.K. and Norkin, C.C. (2005). Joint structure and function: A comprehensive analysis (4th ed.). Philadelphia: The F.A. Davis Company.
7. ↑ Brody, L.T.:Shoulder. In: Wadsworth, C.(ed.)(2001). Current concepts of orthopedic physical therapy: Home study course. LaCrosse, WI: Orthopaedic Secion, APTA, Inc.
8. ↑ Conway, A.M. (1961). Movements at the sternoclavicular and acromioclavicular joints. Phys Ther Rev. 41: 421-432.
9. ↑ Levangie, P.K. & Norkin, C.C. (2005). Joint structure and function: A comprehensive analysis (4th ed.). Philadelphia: The F.A. Davis Company.
10. ↑ Disorders of the sternoclavicular jointfckLRC. M. Robinson, BMEdSci, FRCS Ed(Orth and Trauma), Consultant Orthopaedic Surgeon1; P. J. Jenkins, MRCS Ed, Specialty Registrar,
11. ↑ ↑