Shoulder Anatomy
Shoulder Fracture – In this article I’m doing to talk about Shoulder Fracture. The shoulder is formed where the humerus, collar bone (clavicle), and scapula join. The rotator cuff holds the humerus in place. The muscles that form the shoulder are the supraspinatus, infraspinatus, tres minor, subscapularis, and deltoid. There are four rotator cuff tendons and two biceps tendons that make up the shoulder. These tendons connect the deep layers of the muscles to the scapula and humerus and provide support to the glenohumeral joint. The supraspinatus tendon is the most affected tendon due to overuse and trauma. The supraspinatus muscle is responsible for lifting the arms out to the side. An injury to this muscle can result in a possible rotator cuff tear or tears. Overuse can lead to shoulder (subacromial) impingement.
Shoulder Fracture
A shoulder fracture can occur after falling directly onto the shoulder with the arm either tucked or restrained to the body. This type of injury usually occurs in male athletes who play contact sports such as football, rugby, wrestling, and mixed martial arts. Shoulder fractures can also occur from motor vehicle accidents, also. This particular injury causes tears in the ligaments surrounding the AC joint(located between the acromion process and collar bone). When someone falls with an outstretched arm, the distal clavicle and acromion process may fracture. Injury to the AC joint can damage the cartilage within the joint, which can later cause arthritis in the AC joint.
There are three types of shoulder fractures: scapular, clavicle, and humerus.
1). Scapular Fracture
The scapula is the triangular bone located in the upper portion of the back. It connects the arm to the chest.Scapula fractures are very uncommon, but they can occur from severe direct trauma to the upper thoracic and scapular area.Patients with a fractured scapula often present with posterior shoulder and thoracic area swelling, tenderness, and bruising. Most of the time, when patients have a scapula fracture, they will have a life-threatening injury to their lungs, ribs, and nerves that will result in the scapular fracture treatment being delayed until the patient is stabilized. If this is the case, and the scapula is severely displaced, then surgery will be needed. However, most scapula fractures do not require surgery due to minimal displacement and strong muscle support. Instead, patients will wear a sling for short-term immobilization. Once the sling is no longer necessary and pain has improved, patients will be referred to physical therapy for progressive range-of-motion exercises until they have achieved full recovery. Most scapula fractures heal in 6 weeks.
2). Clavicle (Collarbone) Fracture
The clavicle is the long bone that begins at the base of the neck and extends to the shoulder. Clavicle fractures are very common and often happen when athletes (especially ones who participate in hockey, soccer, roller blading, skiing, bicycling, or horseback riding), particularly football players, fall directly onto their shoulder with their arm outstretched or tucked close to their body. I remember watching Aaron Rodgers, quarterback of the Green Bay Packers,being tackled during an NFL game in 2017 against the Minnesota Vikings. This resulted in him breaking his right collarbone. Patients who experience this injury report hearing a snapping or cracking sound when they break their collar bone. They complain of front upper shoulder pain and swelling. Deformity over the clavicle may be observed asone shoulder may look shorter than the other (one side droops).
Patients with a broken clavicle will complain of difficulty breathing and have shallow breath sounds, which indicate a lung injury. Patients may also have vascular injuries such as a diminished pulse, swelling, and decreased blood flow (venous stasis), which may result in blood clots (venous thrombosis). If you suspect that anyone has any of these signs or symptoms, please go directly to the ER for medical treatment.This will entail labs (blood work) to assess arterial blood gases; X-rays of the clavicle, shoulder, chest (assess pneumothorax or hemothorax), ribs; and CTs to evaluate possible fractures and neurovascular injuries. Depending on the severity of vascular and pulmonary (lung) injuries, patients will be referred to either a vascular surgeon or a general/thoracic surgeon.
Treatment for a clavicle fracture depends on the imaging results. Most clavicle fractures will heal without surgery. Wearing a shoulder sling may be necessary; however, not all clavicle fractures are the same. Fractures can occur in different parts of the bone. For example, if a fracture occurs in the middle of the clavicle, surgery is typically not required. If the fracture is medial, then surgery is possible, but may not be likely. Last, if the fracture occurs laterally (near the acromion), then surgery may or may not be required. Patients will be referred to an orthopedic surgeon for a consultation for a possible surgical fixation.
3). Humerus Fracture
There are two types of humerus fractures, proximal and distal. Proximal humeral fractures occur in older patients with osteoporosis. They are often caused by falling while standing, falling down the stairs, ormotor vehicle accidents. Patients with possible proximal fractures often complain of pain while moving their shoulder and elbow. Bruising and swelling of the affected shoulder and arm will be present. Most proximal fractures are non displaced and typically will not require surgery.
Distal humerus fractures are associated with ipsilateral proximal forearm fractures. This type of fracture occurs in younger patients. The best treatment plan is minimizing movement, taking NSAIDS for pain management, and applying ice compresses to relieve pain and to reduce swelling. An immediate trip to the ER for evaluation is necessary. Surgery is based on the results of the X-ray and the severity of the displacement.
The humeral head connects to the scapular glenoid. There are four parts to the humeral head: the neck, the greater tuberosity, the lesser tuberosity, and the humeral shaft. The greater tuberosity fracture should have ultrasound or an MRI to check for integrity of the rotator cuff. Blood is supplied to the humeral head from branches of the axillary artery. A fracture to the neck may affect the blood supply and result in avascular necrosis of the humeral head. A proximal humeral head fracture can be managed without surgery. A sling tends to be the primary treatment.
Fractures of the anatomical neck should be referred to an orthopedic specialist because of the risk of avascular necrosis. Humerus shaft fracture is stabilized by a coaptation splint. A fracture reduction is not necessary due to the difficulty of maintenance.
References
Alila Medical Media. (2019). Shoulder bursa, bursitis. [Illustration]. Retrieved from https://www.shutterstock.com/image-illustration/shoulder-bursa-bursitis-122298685?src=LgujqAxYpFEk2V8pW5kcBw-1-8
Goss, T., Cantu, R., Talavera, F., Mooar, P., &Hasan, A.S. (2020). Scapula Fracture. Retrieved from https://emedicine.medscape.com/article/1263076-overview
OrthoInfo. (2020). Clavicle Fracture (Broken Collarbone). Retrieved from https://orthoinfo.aaos.org/en/diseases–conditions/clavicle-fracture-broken-collarbone/
Srivastava, A., Aronson, A., Mills, T., Legome, E., &Talavera, F. (2019). Humerus Fracture. Retrieved from https://emedicine.medscape.com/article/825488-overview#showall
Udaix. (2020). Shoulder Joint of the Human Body. [Illustration]. Retrieved from https://www.shutterstock.com/image-vector/shoulder-joint-human-body-anatomy-infographic-699043855