Where Does My Shoulder Pain Come From? ーUnderstanding the Connection Between Bones and Muscles ーAugust 3, 2026 (Monday) Reiwa8
After surgery for a left proximal humerus fracture, I still feel a heavy pain throughout my left arm.
When I woke up, the pain was especially strong, and my entire arm felt heavy. However, as time passed, the pain medicine seemed to take effect, and talking while thinking about my body also helped me relax a little.
Today, while studying anatomy again, I realized that the shoulder does not move by the shoulder alone.
The movement of the shoulder is created by the connection between:
The sternum
↓
The clavicle
↓
The scapula
↓
The humerus
Many muscles work together to create smooth movement.
## The Relationship Between the Humerus and the Shoulder
The upper part of the humerus, where I had my fracture, is an important area that forms the shoulder joint.
The head of the humerus fits into the glenoid cavity of the scapula, creating the shoulder joint and allowing a wide range of arm movement.
However, because the shoulder joint has such a wide range of motion, it depends greatly on muscles and tendons for stability.
Important muscles involved include:
- Deltoid muscle
- Rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis)
- Biceps brachii muscle
- Pectoralis major and pectoralis minor
- Trapezius muscle
- Levator scapulae muscle
- Rhomboid muscles
- Teres major muscle
- Latissimus dorsi muscle
## The Relationship Between My Pain and My Muscles
The movement that feels most difficult now is raising my arm forward.
My right arm can rise straight upward, but my left arm cannot. My shoulder does not rise enough, and my elbow bends as my arm stops halfway.
This may happen because the muscles and joint around my shoulder have not yet returned to their normal movement after the fracture and surgery.
My body may also be unconsciously avoiding pain by changing the way I move.
Another painful movement is when I hold my hands above my head and lower them down.
This movement requires:
- Shoulder joint movement
- Scapular movement
- Stretching of the chest muscles
- Flexibility of the tissues in the front of the shoulder
## Pain in the Front of the Shoulder
My surgical scar is on the front of my shoulder, about 5–10 cm long.
The front area of the shoulder contains:
- The anterior part of the deltoid muscle
- Pectoralis major muscle
- Pectoralis minor muscle
- Tissues around the long head of the biceps tendon
Therefore, these tissues may be related to the pain I feel when lifting my arm forward.
## The Importance of the Back Muscles
The shoulder is not only connected to the front of the body. The back muscles also play an important role.
The trapezius is a large muscle extending from the neck to the shoulder blade and back. It helps control the position and movement of the scapula.
The latissimus dorsi and teres major are back muscles, but they attach to the humerus, so they are also involved in arm movement.
After shoulder surgery, protecting the injured arm can place extra stress on the neck and back muscles, which may contribute to the heavy feeling and pain throughout the arm.
## My Recovery So Far
Although the pain is still strong, there has been some improvement.
Previously, I could not hang laundry or attach socks to clips. Now I can do these small daily movements with much less pain.
This shows that some function is gradually returning.
The shoulder is a complex area where many bones and muscles work together.
Through this fracture and surgery, I have learned again that the body does not work as separate parts. Everything is connected.
I still wonder when this pain will finally disappear, but I want to continue observing my body, understanding it, and recovering step by step without rushing.
### Hashtags
#LeftProximalHumerusFracture
#ShoulderRehabilitation
#ShoulderAnatomy
#ConnectionBetweenBonesAndMuscles
#DeltoidMuscle
#TrapeziusMuscle
#LatissimusDorsi
#Scapula
#RecoveryJourney
#ChallengeTowardTheFuture
