Shoulder pain — All You Need To Know.

What Are The Caus­es Of Shoul­der Pain? Shoul­der pain can make a sim­ple move ( brush­ing or dry­ing your hair, reach­ing behind your back, or grab­bing some­thing over­head ) seems like a Her­culean task. Read On To Learn More and Know The Causes. This arti­cle was writ­ten by Dr. Islam Elna­gar. M.D, FRCSC, Orthopaedic Surgeon.

Why Is My Shoulder Aching ?

There is a big list of caus­es for Shoul­der pain. Few of these caus­es are not orig­i­nat­ing from the shoul­der joint itself, known as; Referred pain. The caus­es of Shoul­der pain might dif­fer from one per­son to anoth­er accord­ing to gen­der, age, lifestyle, occu­pa­tion and gen­er­al med­ical condition. Before we dis­cuss this list, we would like to enu­mer­ate few facts about the Shoul­der joint. 1- It is com­posed of an artic­u­la­tion between the Humerus Head and the Gle­noid ( part of the Scapula ). 2- It has the biggest range of motion of any joint in the body. 3- It is the most com­mon­ly dis­lo­cat­ed joint, with ante­ri­or dis­lo­ca­tion being the most common.

Causes Of Shoulder Pain

1- Shoulder Arthritis

A preva­lent cause of shoul­der pain, espe­cial­ly in old­er peo­ple. Age is just a num­ber, but in gen­er­al, by 50–60 years, arthri­tis becomes a com­mon cause of joints pain ( Shoul­der, hip, knee, etc.). Arthri­tis can be idio­path­ic ( no cause ) or sec­ondary to sys­temic dis­ease, trau­ma, etc.  Dis­crim­i­na­tor: Usu­al­ly, the pain increas­es with activ­i­ty and decreas­es with rest unless the arthri­tis is advanced, lead­ing to the ongo­ing con­stant pain.

2- Rotator Cuff Diseases

Rota­tor cuff pathol­o­gy is com­mon among younger and old­er patients. A spec­trum of dis­eases affect the Rota­tor cuff as; impinge­ment, inflam­ma­tion, par­tial or full tears. Dis­crim­i­na­tor: With impinge­ment or small tears, the pain is usu­al­ly at the extreme range of motion as the mus­cles impinge on the bony struc­tures. In big tears, the pain could be con­stant and asso­ci­at­ed with much decrease in range of motion, plus night pain could occur.

3- The Long Head Of The Biceps Muscle

The biceps mus­cle has two heads; long and short ones. The long head is intra-artic­u­lar, mean­ing it runs in the joint. This long head can get inflamed ( syn­ovitic ) or even get torn; it will cause ante­ri­or shoul­der pain and upper arm pain in both cases. Dis­crim­i­na­tor:  Pain is usu­al­ly locat­ed in the ante­ri­or aspect of the shoul­der, just dis­tal to the joint ( on the upper arm ).

4- Labral Injuries

The labrum is the soft tis­sue lin­ing around the gle­noid. It helps to pro­vide sta­bil­i­ty by increas­ing the depth of the gle­noid ( socket ). Labral injuries can be acute or chron­ic. Chron­ic injuries ( also known as degen­er­a­tive ) can cause deep shoul­der pain with range of motion. Acute injuries are more com­mon in younger patients; this could be due to a sin­gle trau­mat­ic event or ongo­ing repet­i­tive load to the joint. Dis­crim­i­na­tor: Deep joint pain which could be asso­ci­at­ed with click­ing, espe­cial­ly in cas­es of acute injuries in younger patients or could be asso­ci­at­ed with the sen­sa­tion of insta­bil­i­ty in acute cas­es sec­ondary to dis­lo­ca­tion ( in this case, it might be a pain­less sen­sa­tion of insta­bil­i­ty with an almost full range of motion ). In old­er patients with chron­ic degen­er­a­tive labral injuries, the pain is mild and sim­i­lar to arthrit­ic pain.

5- Acromioclavicular Joint Arthritis

The acromio­clav­ic­u­lar joint is a small joint with very lit­tle motion locat­ed ante­ri­or­ly and on top of the main shoul­der joint ( Gleno­humer­al joint ). This artic­u­la­tion is between the Acromion ( part of the scapula/shoulder blade ) and the Clav­i­cle ( col­lar bone ). This joint might get arthrit­ic ( nar­row­ing of the space ), caus­ing pain very well local­ized ante­ri­or­ly yet can be per­ceived as shoul­der pain. Dis­crim­i­na­tor: Localised point of pain/tenderness over the joint on the ante­ri­or aspect of the shoul­der region. This is usu­al­ly not asso­ci­at­ed with decreased range of motion nor night pain if it occurs in isolation.

6- Nerve Pain

Few nerves run around the shoul­der as; Axil­lary, Supras­capu­lar, and Infra­scapu­lar nerves. Impinge­ment of any of these nerves around the shoul­der would cause pain ( usu­al­ly sharp shoot­ing pain ). Dis­crim­i­na­tor: Sharp shoot­ing pain ( rather than aching pain ), referred down to the arm.

7- Brachial Plexus Injury

The brachial plexus is the bun­dle of nerve trunks and cords aris­ing from the neck and feed­ing the whole upper extrem­i­ty down to the fin­ger­tips. Brachial plexus injuries due to sys­temic dis­eases or sec­ondary to trau­ma will cause shoul­der pain. Dis­crim­i­na­tor: As in nerve pain, sharp shoot­ing pain with weak­ness in the mus­cles involved and decreased sen­sa­tion in the affect­ed der­matomes in the arm/forearm/wrist and hand.

8- Neck Pain

Also called referred pain since the pathol­o­gy is not orig­i­nat­ing from the Shoul­der joint itself. This is a preva­lent cause of pain that could be thought of as shoul­der pain, yet the shoul­der is non-patho­log­ic, yet it just per­ceives the pain. Neck patholo­gies as degen­er­a­tive disc dis­ease, spinal steno­sis, foram­i­nal steno­sis ( fora­men where the nerve root exits the spinal cord ) or paraspinal mus­cle spasm can cause neck and shoul­der pain. This pain can be asso­ci­at­ed with numb­ness, tin­gling and maybe weak­ness down to the hand lev­el, which is very uncom­mon in true shoul­der pain when the pathol­o­gy orig­i­nates from the joint. Dis­crim­i­na­tor: Pain in the neck and/or the parac­er­vi­cal mus­cles that might be increased with neck range of move­ments, plus pain/numbness and tin­gling radi­at­ing down the arm.

9- Infection

This is uncom­mon with­out pre­dis­pos­ing fac­tors as shoul­der surgery, open frac­ture or under­ly­ing immuno­com­pro­mised dis­ease, yet it can also occur spon­ta­neous­ly. This can be pre­sent­ing as cel­luli­tis or shoul­der joint infec­tion. It is usu­al­ly asso­ci­at­ed with red­ness, swelling, decreased shoul­der range of motion, fever etc. Dis­crim­i­na­tor: Con­stant aching pain even at rest asso­ci­at­ed with skin red­ness, swelling, and sys­temic changes as fever and chills.

10- Inflammation

For exam­ple; Bur­si­tis ( which is dif­fer­ent from the infec­tion since there is no pathogen). It is inflam­ma­tion of the tis­sue either inside the shoul­der joint or in sub­acro­mi­al space or extra-articular. The intra-artic­u­lar usu­al­ly presents as the rota­tor cuff pathol­o­gy, while the extra-artic­u­lar could present with red­ness and swelling. Dis­crim­i­na­tor: Like rota­tor cuff pathol­o­gy, the super­fi­cial bur­sae can present with red­ness and swelling plus focal local­ized pain.

11- Frozen Shoulder ( also known as Stiff Shoulder )

It can occur with­out any rea­son but is more com­mon­ly present after shoul­der surgery, more in females, dia­bet­ics, breast can­cer treat­ment, car­dio­vas­cu­lar dis­eases, myocar­dial dys­func­tion, thy­roid dys­func­tion, and seden­tary life. Dis­crim­i­na­tor: Decreased range of motion usu­al­ly starts with exter­nal rota­tion defi­cien­cy, and pain increas­es with the range of motion. The pas­sive range of motion will be equal­ly affect­ed as well.

12- Scapular Pain

This can be due to few rea­sons as trau­ma or dysk­i­ne­sia ( altered scapu­lar posi­tion and motion ). Dysk­i­ne­sia can be due to; Kypho­sis, clav­ic­u­lar frac­ture malu­nion or nonunion, or scapu­lar winging. Dis­crim­i­na­tor: Usu­al­ly, there is either his­to­ry of trau­ma or defor­mi­ty on phys­i­cal examination

13- Trauma

This could lead to frac­tures ( prox­i­mal humerus frac­ture, scapu­lar frac­ture, Acromio­clav­ic­u­lar joint sep­a­ra­tion etc.), dis­lo­ca­tions or soft tis­sue injury. If treat­ment of any of these was ignored or mis­man­aged, this might lead to Shoul­der pain. Dis­crim­i­na­tor: His­to­ry of trau­ma, if you had a fall or acci­dent, you should be checked by a med­ical doc­tor (i.e. don’t ignore your first injury, occa­sion­al­ly we see injuries weeks or months after the ini­tial inci­dent, which some­times lead to sub­op­ti­mal outcomes).

14- Muscular

The mus­cles around the shoul­der can get fatigued over time. This can be due to age­ing or ongo­ing abnor­mal posture. A com­mon dis­ease in this cat­e­go­ry is called; Upper Cross Syn­drome, where the neck, upper back, shoul­der, or chest mus­cles become deformed and acquire dif­fer­ent non-anatom­ic posi­tions lead­ing to a change in the dynam­ics and even­tu­al­ly ongo­ing pain. Dis­crim­i­na­tor: This usu­al­ly occurs in peo­ple who sus­tain cer­tain posi­tions for long hours as; sit­ting on a desk in the wrong way for a long time, bik­ing, dri­ving etc.

15- Systemic Disease

A big list of dis­eases that can lead to joint pain as; Inflam­ma­to­ry Arthri­tis, Fibromyal­gia, Mul­ti­ple Scle­ro­sis, etc. ( the list goes on ). Even car­diac con­di­tions as a heart attack can present with left shoul­der pain. Dis­crim­i­na­tor: His­to­ry of sys­temic dis­ease ( If you have a known med­ical con­di­tion, you can review its clin­i­cal pic­ture and talk with your doctor ).

When to Seek Professional Help for Pain

Ongo­ing or wors­en­ing pain is a sign that your body needs prop­er atten­tion, not guess­work. When it comes to shoul­der pain, ignor­ing symp­toms or rely­ing on self-treat­ment can delay heal­ing and some­times lead to more seri­ous issues. A trained pro­fes­sion­al can iden­ti­fy the under­ly­ing cause, rec­om­mend appro­pri­ate treat­ment, and help pre­vent long-term damage. This is espe­cial­ly impor­tant in sit­u­a­tions involv­ing trau­ma, such as recov­ery after auto acci­dent, where pain may not ful­ly appear until days or weeks lat­er. Ear­ly assess­ment ensures injuries are addressed cor­rect­ly and sup­ports a safer, more com­plete recovery.

In Summary

Shoul­der Pain can be due to a huge list of caus­es, as men­tioned. The key to diag­no­sis depends on tak­ing a good his­to­ry, know­ing the asso­ci­at­ed med­ical con­di­tions and arrang­ing the appro­pri­ate inves­ti­ga­tions. Our rec­om­men­da­tion is to seek med­ical advice with­out delay!