Avascular Necrosis of the Shoulder

Avascular necrosis is death of a segment of bone. AVN may affect the proximal humerus due to interruption of the blood supply. The ascending branch of the anterior humeral circumflex artery runs in the lateral bicipital groove and then becomes the arcuate artery. The other artery that is important to the blood supply is the posterior humeral circumflex artery.

avascccc

There are several risk factors for AVN including: Alcohol, Systemic Lupus Erythematosus, infection, trauma, and steroid use. 5-25% of AVN cases are due to steroid usage. Steroids increase the serum lipids in the blood which may precipitate fat embolism into the humeral head blood vessels.

posttrauma

proximal humeral pain

Progressive collapse of the humeral head occurs due to bone death, reabsorption, remodeling, micro fractures and final collapse with joint changes and arthritis. Symptoms include: shoulder pain, weakness, crepitus, and a decreased range of motion. Symptoms are gradual and insidious with delay in the diagnosis and treatment. The patient usually has a history of risk factors.

osteomri

In regards to imagining, x-rays will show the best in the neutral rotation AP view. AVN located on the superior middle part of the humeral head just deep to the articular cartilage. If the crescent sign is seen, this is an indicator of collapse. An MRI is going to be the best imaging study. A patient with AVN of the humerus should have a hip radiograph. If the x-ray is negative and the patient has hip pain, you should obtain an MRI of the hip. It is recommended that a patient with osteonecrosis at the site of the shoulder should undergo an MRI of the hip to rule out asymptomatic osteonecrosis of the hip. You may also need to do an x-ray of the knee. AVN may involve three or more anatomic sites (multifocal osteonecrosis).

Treatment typically consists of:

  • Physical Therapy
  • NSAIDS
  • Core decompression for Stage I and Stage II
  • Resurfacing for Stage III
  • Hemiarthroplasty for Stage III and Stage IV
  • Total shoulder surgery for Stage V
    • Advanced disease
    • The results of total shoulder are inferior to patients with osteoarthritis

 

Tarsal Coalition

Tarsal coalition is a congenital anomaly in which the tarsal bones fuse together, leading to a rigid flat foot, foot pain, and multiple ankle sprains. There are two types of tarsal coalition. The first is known as a Talocalcaneal Coalition, which is a coalition between the talus and the calcaneus. The second is referred to as a calcaneonavicular coalition which is a coalition between the calcaneus and the navicular. When talocalcaneal coalition occurs, it usually happens around 12-15 years of age. The calcaneonavicular coalition presents at an earlier age. About 50% of coalitions are bilateral, and around 20% have multiple coalitions in the same foot. Coalition may be fibrous, cartilaginous, or bony and occurs due to failure of segmentation. It could be associated with fibular hemimelia or Apert’s syndrome.

tarsal anatomy

Symptoms typically consist of patient’s complaining of a painful foot, a history of repeated ankle sprains, and a flat foot deformity. Tarsal coalition may result in a peroneal spastic flat foot. During the physical examination, the physician may find hindfoot valgus. On toe standing, the arch does not reconstitute and heel cord contracture may also be evident during the exam. Furthermore, there may be restriction in the subtalar joint’s range of motion. It is important to check both feet as the condition may be bilateral.

hindfoot

The best imaging study is a CT scan. It can determine the size and location of the coalition. And MRI is also useful in detecting a fibrous or cartilaginous coalition. AP, Lateral, and Oblique view x-rays should be ordered. On a lateral view x-ray, the Calcaneonavicular Coalition can be identified by the “anteater nose sign” and the elongation of the anterior calcaneal process.

ant

A lateral view of a Talocalcaneal Coalition may show talar beaking which is a traction spur that occurs due to the limited motion of the subtalar joint. Additionally, the C sign may be seen which is a radiological sign outlining the talar dome and the sustentaculum. A 45° oblique view is the best for showing calcaneonavicular coalitions.

45oblique

Nonoperative treatment usually consists of anti-inflammatory drugs, modified activities, or the use of a brace or cast. Surgical treatment for the calcaneonavicular coalition usually consists of resection with an interposition of the extensor digitorum brevis muscle or a fat graft no matter the size of the coalition. Similarly, Talocalcaneal coalitions that involve less than 50% of the subtalar joint are also resected. A triple arthrodesis procedure is performed for large coalitions, failed resections, or advanced conditions.

Low Back Pain- Disc Herniation

The spine is comprised of bony vertebrae separated by discs. The neural structures of the spine include the spinal cord (T12-L1), The conus medullaris—which is the lower end of the spinal cord, and the Cauda Equina, which is the division of multiple nerve roots beginning at the level of L1. Conditions of the lumbar spine including disc herniation are a main cause of lower back pain.

needs edits

The lumbar spine (lower back) consists of five vertebrae numbered L1-L5. These vertebrae are attached to the sacrum at the lower end of the spine. The discs between the vertebrae are round cushioning pads which act as shock absorbers. In a normal disc, there are two layers—the inner disc layer, which is comprised of soft gelatinous tissue and known as the Nucleus Pulposus, and the outer disc layer—which is made up of thick strong tissue, which is known as the Annulus Fibrosis. Behind this disc lies the spinal nerve root and the cauda equina. A major disc herniation of the lumbosacral region could affect the nerve roots.

parts

 

In about 95% of all disc herniation cases, the L4-L5 or L5-S1 disc levels are involved. Herniation of the L4-L5 disc will affect the L5 nerve root. Herniation of the L5-S1 disc will affect the S1 nerve root.

spinesections

There are three types of disc herniation:

  1. Protrusion/ Bulge- A bulging disc with intact annular and posterior longitudinal ligament fibers
  2. Disc Herniation
    • Type A—Disruption of inner annular fibers with intact outer annular fibers
    • Type B—Disrupted annulus with tail of disc material extending into the disc space
  3. Sequestration
    • Free fragment without tail extending into disc space
    • Fragment may be reabsorbed spontaneously
    • May get better with the use of an epidural

sequest

There are three typical locations for disc herniation as well:

  1. Central
    • Involves multiple nerve roots
    • Predominantly causes low back pain more than leg pain
    • May cause incontinence of the bladder and bowel
    • Urgent surgical treatment if patient presents with neurological deficits
  2. Posterolateral—usual location, most commonly involving one nerve root (the lower one)
    • For example: L4-L5 posterolateral herniation will involve L5 nerve root
  3. Foraminal
    • Occurs in 8-10% of cases
    • Involves the exiting nerve
    • Example: L4-L5 foraminal herniation will involve the L4 nerve root

Discogenic Back Pain is an internal disc disruption with early disc degeneration. Pain gets worse with flexion and sitting but, gets slightly better with extension. Forward flexion is limited on the exam and there are no radicular symptoms.