Shoulder Joint Pain Reasons
One of the first questions any patient asks when obtaining an injury is ‘how long until it gets better’... If only an answer were simple.
Unfortunately, when it comes to the shoulder joint, the answer isn’t straightforward at all because your shoulder is one of the most complicated joints in your body.
To achieve the wide range of movement that the shoulder provides, it requires a combination of muscles from body to shoulder blade (scapula), body to arm bone (humerus) and shoulder blade to arm bone. Due to this complexity, it is one of the most susceptible joints in the body to injury.
The shoulder is made up of three bones, the upper arm bone (humerus), the shoulder blade (scapula) and the collarbone (clavicle). There are joints between the clavicle and scapula and between the scapula and humerus.
The stability of the shoulder is predominantly controlled by four muscles, commonly known as the rotator cuff. They are tasked with keeping the joint properly centred and located.
These are
- Supraspinatus
- Infraspinatus
- Subscapularis
- Teres Minor
Common Shoulder Problems
The most common shoulder injuries are:
- Rotator cuff tears/tendonitis
- Impingement
- Instability
- Frozen Shoulder
- Bursitis
- Osteoarthritis
Rotator Cuff Tears
The rotator cuff muscles and tendons are an important part of the shoulder and are tasked with keeping the bones of the joint together across its wide range of motion. Rotator cuff tears account for more than 50% of shoulder injuries and are most common in people who repeatedly perform overhead motions. Thus athletes involved in sports such as swimming, racquet sports and weight lifting, which all require repetitive overhead movement, are particularly prone to injury.
Typical symptoms of a rotator cuff tear will be pain at night disturbing your sleep, and probably some lessening of pain during the day, although any overhead movement or even reaching behind your back is likely to be painful. You will also probably experience weakness in the affected arm. If left untreated, the pain will most likely increase over time.
Keen athletes may be tempted to continue in their favourite sport, in the hope that the pain will recede, but this will most likely aggravate the situation and, over time, may make the condition worse. If you suspect a rotator cuff tear, it is strongly advised to seek help from a qualified physiotherapist or sports therapist as soon as possible, as some conditions, such as a full-thickness supraspinatus tear, can become irreversible if left too long.
Impingement
Rotator cuff tendons can become trapped between a bony projection of the shoulder blade called the acromion and the top of the humerus (arm bone). Particularly prone is the supraspinatus tendon, this muscle is responsible for moving the top of the arm sideways from the body for about the first 15 degrees of arm movement.
Impingement problems can be caused by a number of factors, including:
- Loss of scapula – humeral rhythm
- Nerve interference or injury from the neck to the shoulder, causing abnormal movement of the shoulder
- Poor posture
- Tears and inflammation of tendons
Instability
Recent dislocation, sudden injury or overuse can each cause shoulder instability. The head of the upper arm bone can glide out of the shoulder socket (glenoid). This can occur when the capsule and ligaments that have the role of stabilising the shoulder in the socket have not healed properly and remain stretched making them too loose to keep the shoulder stabilised. This can result in repeated dislocations.
It is, therefore important to seek treatment. Rehabilitation and soft tissue work can be provided by qualified physiotherapists or sports therapists to help strengthen the muscles and ligaments and help to gain stability around the shoulder joint once more. It is advisable to seek help sooner rather than later.
Frozen Shoulder
This condition, medically described as adhesive capsulitis, can literally develop overnight. The capsule of the joint becomes inflamed and stiff, resulting in restricted movement. Eventually, the shoulder ‘freezes’ and becomes immobile for a few months to a year.
However, a frozen shoulder does typically progress in three main stages:
- Freezing stage- any movement of your shoulder causes pain, and your shoulder's range of motion starts to become limited.
- Frozen stage- pain may begin to diminish during this stage. However, your shoulder becomes stiffer and moving it becomes more difficult.
- Thawing stage- The range of motion in your shoulder begins to improve.
Bursitis
A bursa is a fluid-filled sac that act as a cushion to stop friction between the muscles and bones as they glide over on another. You have several in your shoulder, one being one of the largest in the body which is located towards the top of the arm.
After an excessive repetitive motion of the shoulder, the bursas can inflame and swell. The pain is normally a gradual onset located on the outside of the shoulder which can spread down the arm. It can become more aggravated when lying on the shoulder or if you’re using your shoulder anywhere from 60-90 degrees up and outwards.
When treating Bursitis, the aim is to control the inflammation. If you don’t seek help, often the pain will become worse and become impinged.
Osteoarthritis
This is when the normally smooth cartilage that covers the ball and socket joint diminishes after constant friction leaving bone to grind against bone. It develops slowly and the pain worsens over time, normally after chronic wear and tear or work injuries. Symptoms may include swelling, pain, and stiffness.
Osteoarthritis is a chronic problem which cannot be resolved, but the symptoms of the condition are amenable to pain-reducing treatment.
Every shoulder injury will present differently, and everyone’s perception of improvement will be different too. For example, one patient may be over the moon for gaining an extra 10 degrees in pain-free shoulder motion. Whereas the next will be happy only when gaining their full range of motion back.
Many biological, psychological, and social factors are involved during the recovery process after a shoulder injury.