Epiphyseolysis of the humerus in children

When a fracture of the humerus of the upper extremity is accompanied by damage to the region of its metaepiphysis, leading to displacement of a thin layer of hyaline cartilage - the epiphyseal plate (cartilaginous growth plate), epiphyseolysis of the humerus in children is diagnosed. [1]

Epidemiology

Injuries to the proximal humerus epiphysis have been reported to account for approximately 5% of all fractures in childhood, and epiphyseolysis of the humerus is seen in 24% of upper end fractures.

Injuries to the upper humerus most commonly occur before the age of 10 years and are somewhat less commonly reported between the ages of 11-14 years.

Isolated epiphyseal separation is rare and usually occurs in neonates and young children

Causes of the epiphyseolysis of the humerus in children.

In childhood, all tubular long bones grow from their ends, and at least 80% of the growth of the humerus is due to the proximal (upper) metaepiphyseal cartilage. Growth cartilage is also present in the head of the humerus, the small and large apophyses (tuberosities), the head of the condyle, and the epicondyles of the distal (inferior) epiphysis.

Injuries to bones and joints in children, in particular violations of their integrity, are the main causes of epiphyseolysis of the tubular bones of the immature skeleton. Fracture of the growth plate of the humerus usually occurs from a fall on an outstretched or withdrawn arm (with outward rotation), a fall on the shoulder, or a blow to the arm or shoulder.

Thus, proximal epiphysis of the humerus and rotational stress fracture of its upper epiphyseal plate result in proximal epiphyseolysis of the humerus, and in cases of intra-articular fractures of its head (caput humeri) - epiphyseolysis of the head of the humerus in children.

Fractures of the distal end of the humerus near the epiphysis and articulation with the ulna may result in epiphyseolysis of the cephalic eminence of the humerus in children.

And epiphyseolysis of the condyle of the humerus in children is associated with fractures of the humerus at the site of elbow joint formation, as well as intra-articular fractures of the condyle of the humerus (condylus humeri) in the region of the distal epiphysis.

But in some cases, epiphyseolysis of the humerus can occur due to prolonged overuse of the joint (shoulder or elbow) - with repetitive microtrauma to the cartilage causing damage.

Risk factors

Factors predisposing to shoulder injury with damage to the growth cartilage include:

• Decreased stability of the humerus at the articular socket of the scapula due to weakness or tearing of the rotator cuff of the shoulder;
• Habitual shoulder dislocation;
• joint hypermobility;
• playing sports with increased stress on the shoulder, shoulder and elbow joints;
• Neonatal epicondylar fractures as a result of trauma during childbirth.

Although fractures in childhood are common, some children are more prone to them, and consideration should be given to the increased likelihood of tubular bone fractures in children with inadequate bone density, such as those with hypocalcemia, excessive production of thyroid and parathyroid hormones, in cases of hypercorticism in children or somatotropin (growth hormone) deficiency associated with pituitary anemia, and chronic kidney failure.

Pathogenesis

In metaphyseal lesions of the humerus in children and adolescents - fracture through the growth zone - the pathogenesis is due to the fact that the epiphyseal plates of long tubular bones at this age are, in fact, temporary synchondroses (cartilaginous connections) between the expanded part of the bone body (metaphysis) and the end of the bone (epiphysis). These plates undergo endochondral ossification (begin to be replaced by bone tissue) in girls at 13-15 years of age and in boys at 15-17 years of age.

Therefore, the cartilage growth plate of any tubular bone in children is a weak point when fractures and/or excessive stresses result in a gap or cracking of the cartilage - with damage to the cartilage structure and cartilage displacement.

For more information see - Upper and lower limb bone development

Symptoms of the epiphyseolysis of the humerus in children.

Orthopedists define growth plate fractures as metaphyseal fractures, categorizing their types according to the Salter-Harris system.

In children younger than 5 years of age, a type I fracture affecting the humerus (where the fracture line horizontally crosses the epiphyseal plate, splitting it) is more common, while a type II fracture - where the fracture line passes through the lateral part of the growth plate and then ascends to the metaphysis - is more commonly seen in children older than 12 years of age.

Based on the amount of initial displacement of the metaphyseal cartilage, the stages or degrees of epiphyseolysis (mild, moderate, and severe) are determined.

The first signs of a fracture of the proximal growth zone of the humerus include sudden shoulder pain accompanied by rapid swelling in the shoulder area. Limitation of limb mobility is also noted, and if the head of the humerus is affected, the shoulder joint may appear deformed.

Symptoms of proximal humerus epiphyseolysis associated with microtraumas of the metaepiphyseal cartilage during increased physical (sports) loads may be manifested by pain on palpation over the lateral surface of the humerus, muscle weakness, and restriction of range of motion.

Complications and consequences

After trauma to the proximal humerus, its head or condyles with growth plate displacement, the possible complications and consequences may be:

• curvature of the injured limb in the form of an angular deformity;
• premature closure of the metaepiphyseal cartilage and arrest of longitudinal growth of the humerus;
• enthesopathy of the shoulder or elbow joints;
• osteonecrosis of the humeral head.

Diagnostics of the epiphyseolysis of the humerus in children.

To detect epiphyseolysis of the humerus, history and physical examination are not enough, instrumental diagnosis using x-rays of the humerus in two projections, CT of the upper extremity, ultrasound of the shoulder joint is necessary.

Differential diagnosis

To rule out dissecting osteochondritis, humeral synostosis, fibrous osteodysplasia, osteonecrosis and Ewing's sarcoma, a differential diagnosis is made.

In adolescent athletes, the differential diagnosis includes: rotator cuff injury of the shoulder, inflammation of the tendon of the biceps muscle, rupture of the cartilaginous ring of the shoulder joint, subdeltoid bursitis, compression syndrome of the upper thoracic aperture, and osteochondropathy of the humerus.

Treatment of the epiphyseolysis of the humerus in children.

Treatment of epiphyseolysis of the humerus in children and adolescents - reconstruction of the broken bone by open or closed repositioning.

Conservative treatment usually consists of a plaster cast or splint to immobilize the shoulder for the first two weeks. After that, a coaptation (functional) bandage is used and rehabilitation begins, with doctor-prescribed exercises to gradually increase range of motion. X-rays are repeated every two weeks to make sure the fracture is healing properly.

If the bone fragments are displaced and if there is significant displacement of the metaepiphyseal cartilage in older children (with minimal remaining bone growth term), surgical treatment may be required.

Surgery usually involves percutaneous osteosynthesis or internal fixation of the fracture fragments with plates, screws or pins. Complete healing can take several weeks to several months.

Prevention

Prevention of fractures in children can be considered prevention of epiphyseolysis.

Forecast

A favorable prognosis for epiphyseolysis of the humerus in children can be ensured by proper treatment of its fractures; their improper treatment can result in irreversible limitation of the child's upper extremity mobility.