Interesting case

History

Case: ผปวยชายไทย อาย 18 ป CC: ปวดหวไหลขวา 1 ชวโมง กอนมารพ. PI: 1 ชวโมงกอนมารพ . ขณะเลนฟตบอล ผปาว

ลมตวรบลกบอลไปทางดานขวา มอขวากระแทกพน หลงจากนนมอาการปวด บรเวณหวไหลขวา ขยบหวไหลไมได ยกแขนไมขน ขยบตนแขนไมได ไมไดรบบาดเจบบรเวณศรษะ ไมไดรบบาดเจบบรเวณอน

- ไมมประวตโรคประจำาตว -ไมแพยาไมแพอาหาร

Physical exam

V/S T. 36 PR.68 BP. 121/60 RR.20 GA—A young Thai male,good

consciousness HEENT—Not pale conjunctivae,anicteric

sclerae Heart—Normal s1s2,no murmur Lung—Clear Abdomen—Soft,not tender Extremities—Pain at right shoulder, limit

ROM right arm and right shoulder

Dugar’s sign: positive Ruler’s sign : positive

Dx >> acute anterior shoulder dislocation

Dislocation

Shoulder joint

Glenohumeral ( Shoulder)dislocation

ขอหวไหลเปนขอทหลดบอยทสดของรางกาย เพราะโดยลกษณะ bone anatomy ทเปน large spherical humeral head articulate กบ small shallow glenoid fossa ทำาใหขอนมการเคลอนไหวคอนขางมากและหลดงาย ความมนคงของขอไหลขนกบ soft tissue ( labrum, joint capsule, surrounding muscle ) มากกวา

Incidence

Shoulder is the most commonly dislocated joint

Traumatic Dislocations Anterior 95-97% Posterior 2-4%

Bony Anatomy

Radiographic Anatomy

Stability (static and dynamic stabilizers)Static stabilizers = the bony construct and the capsulolabral

complex1. Glenohumeral joint = ball and socket joint.

Glenohumeral ligaments are lax during the mid-range of motion

and become taut at the extreme position. Glenohumeral joint capsule is a reinforced by the

glenohumeral ligaments. 2. Suction cup effect (negative intraarticular pressure) by capsule and the labrum.3. Rotator interval = capsuloligametous tissue between supraspinatus and subscapular 4.Lubricated synovial fluid.

Conditions that affect the wetability of the joint surface such as arthritis or displaced intraarticular fracture would compromise this mechanism.

Dynamic stability, the rotator cuff, the prime mover, and the periscapular muscles are the main stabilizers.

Static StabilizersThe shoulder joint is composed of 4

articulationsglenohumeral, acromioclavicular,

sternoclavicular, and scapulothoracic

Instability =

The Rotator Cuff Muscles

SupraspinatusInfraspinatusTeres minorSupscapularis

Mechanism of injury

- anterior shoulder dislocation is usually caused by a blow to the abducted, externally rotated, and extended arm (eg, blocking a basketball shot). Less commonly, a blow to the posterior humerus or a fall on an outstretched arm may cause an anterior dislocation.- posterior shoulder dislocation A blow to the anterior portion of the shoulder, axial loading of an adducted and internally rotated arm, or violent muscle contractions following a seizure or electrocution represent the most common causes of posterior shoulder dislocation

Clinical Presentation

Pain on affected side Holds the injured

limb with other hand close to the trunk

The shoulder is abducted and the elbow is kept flexed

There is loss of the normal contour of the shoulder

Physical Examination

Loss of the contour of the shoulder may appear as a step

Anterior bulge of head of humerus may be visible or palpable

A gap can be palpated above the dislocated head of the humerus

Physical Examination

Limited ROM Dugar’s sign Ruler’s sign

Associated injuries of anterior Shoulder Dislocation Injury to the neurovascular bundle in

axilla (rare) Injury of the axillary nerve (Usually

stretching leading to temporary neurapraxia)

Associated fracture

Investigations

Shoulder series AP Transcapula Transaxillary

Investigations

Shoulder series AP Transcapula Transaxillary

A-P: anteroposterior.

An A-P radiograph with internal rotation (A) shows the position of the greater tuberosity (arrow). With external rotation (B), the greater tuberosity becomes more obvious (arrow).

Scapular (Y-view)

This radiograph utilizes a scapular Y-view of the shoulder to assess the location of the humeral head. Anterior or posterior dislocation are excluded by a normal position of the humeral head (HH) relative to the coracoid (C) and the acromion process (A). The inferior portion of the "Y" is formed by the body of the scapula (S).

Axillary view

An axillary view of a normal shoulder shows the components of the shoulder including the glenoid (g), humeral head (h), coracoid process (c), clavicle (cl), lesser tuberosity (lt), acromion (a), and greater tuberosity (gt).

• AP:humeral head อยใน glenoid fossa, หางจาก anteriorglenoid rim < 6 mm,

ดcortex/trabecular pattern,acromio-humeral distance 9-10 mm, calcification รอบขอหรอไม

• Lateral scapular: humeral head วางอยตรงกลาง glenoid cavity

Type of Anterior Shoulder Dislocation

Management

Pre-Medication

Reduction Maneuvers

Post-Reduction Immobilization

Pre-Medication

Methods of Premedication prior to Reduction

None Intraarticular Lidocaine IV Sedation Supraclavicular Block Suprascapular Block

Reduction technique

Stimson technique ( If the above techniques are unsuccessful )

- placing the patient prone and hanging the affected extremity off the edge of the bed with 10 to 15 pounds of weight

- Reduction is usually achieved within 30 minutes.

Stimson’s Technique

Reduction technique

Traction countertraction - employs a sheet wrapped under the

axilla. - While one assistant provides gentle

continuous traction at the wrist or elbow, the other provides countertraction with the sheet from the opposite side of the patient

Traction Counter Traction Method

Zero position technique เรมดงเบา ๆ พอใหแขนอยในทา Extend Elbow โดยไมออกแรง

ดงใหตวผปวยขยบตาม เรม Abduction ของ Shoulder ชา ๆ จนถง 90 แลวลด

ความเรวของการทา Abduction หรอหยดชวคราว เรมขยบจาก Abduction 90 จนได Full Abduction of

Shoulder (ตนแขนชดห ) สงเกตวาแขนของผปวยจะมการหมน (External rotation) ใหหมนแขนตาม (External rotation) โดยการขยบมอสองขางอยางเหมาะสม

คางแขนของผปวยไวในทา Full Abduction จนไดความรสกวาเกด Reduction หรอผปวยรสกหายจากอาการตง ๆ บรเวณไหล ใหเรมลดมม Flexion ของ Shoulder

FOLLOW-UP CARE - After successful reduction,shoulder is immobilized

and referred to an orthopedic surgeon within 1 week. - most common complication of shoulder dislocation

is recurrent dislocation 50 - 90 % under the age of 20

5 - 10 % over age 40 - Efforts to prevent redislocation include altering the

position of immobilization, increasing the duration of immobilization, physical therapy, and operative repair.

Immobilization - The best position in which to

immobilize the shoulder after reduction remains controversial.

- We suggest immobilizing the shoulder in the traditional position of adduction and internal rotation.

- A collar and cuff, sling and swathe, or a commercially available shoulder immobilizer are equally effective.

- In patients under 30 years old, the shoulder is immobilized for 3 weeks - In patients over 30 years old, the rate of redislocation is lower and early mobilization (after 1week) is needed to limit joint stiffness

-Gentle pendular motion exercises should be performed during the immobilization period to reduce the risk of frozen shoulder.

- recurrent dislocation might be less likely if the shoulder were immobilized in 10 degrees of external rotation

- detachment of the glenoid labrum (ie, Bankart lesion) is the major reason for high redislocation rates among younger patients.

- If the shoulder were immobilized in external rotation, the damaged and intact parts of the glenoid labrum would lie closer to one another and be more likely to heal .

- While this theory makes intuitive sense, the evidence available from randomized trials does not demonstrate lower redislocation rates among patients immobilized in external rotation

Complications

Axillary nerve injury Neurovascular injury (rare) Associated fracture of neck of

humerus or greater or lesser tuberosities

Recurrent dislocation

http://www.uptodate.com/contents/shoulder-dislocation-and-reduction?source=search_result&search=reduction+shoulder+dislocation&selectedTitle=1%7E2

http://www.uptodate.com/contents/image?imageKey=EM%2F60699&topicKey=SM%2F258&rank=1%7E2&source=see_link&search=reduction+shoulder+dislocation&utdPopup=true

http://www.uptodate.com/contents/physical-examination-of-the-shoulder?source=see_link

References