Hip Fractures Types & Classifications

Femoral neck fractures can occur as a result of low energy trauma as in the elderly. Femoral neck fractures can also occur due to high energy trauma, such as with falls or motor vehicle accidents. Anatomic classification of femoral neck fractures includes subcapital, transcervical, basicervical. Subcapital is common. There are two famous classifications of subcapital fractures: Garden classification and Pauwel’s classification. Garden classification classifies the fractures according to the amount or degree of displacement. There are four types. It relates the amount of displacement to the risk of vascular disruption. This classification applies to the geriatric and insufficiency fractures.it is classified into two groups: nondisplaced are type I and type II, and displaced are type III and type IV. Garden classification type I is incomplete and impacted in valgus. Type II fracture is complete and nondisplaced on at least two planes (anteroposterior & lateral). Type III is a complete fracture and partially displaced. The trabecular pattern of the femoral head does not line up with the acetabular trabecular pattern. Type IV is a completely displaced fracture with no continuity between the proximal and distal fragments. The trabecular pattern of femoral head remains parallel with the acetabulum trabecular pattern. There are three types within the Pauwel’s classification. Pauwel’s classification classifies the fracture according to the orientation and direction of the fracture line across the femoral neck. It relates to the biomechanical stability. The more vertical the fracture, the more shear forces, and the more complication rate. Type I has an obliquity ranging from 0-30 degrees. Type II has an obliquity ranging from 30-50 degrees. Type III has an obliquity between 50-70 degrees or more. As the fracture progresses from Type I- Type III, the obliquity of the fracture line increases. As the fracture line becomes more vertical, the shear forces increase and the instability increases. A horizontal fracture is good and stable. A vertical fracture is bad and unstable. The more displaced the fracture, the more disruption of the blood supply and the chance of avascular necrosis and nonunion (can occur in about 25% of displaced fractures). If nonunion occurs in a younger patient, you may help the patient by doing subtrochanteric osteotomy to reorient the fracture line from vertical to horizontal (will help the fracture healing). In femoral neck fractures associated with femoral shaft fractures, the typical neck fracture is vertical and nondisplaced. It may require internal rotation view x-rays to see this hip fracture (fracture could be missed). Fix the femoral neck fracture first, followed by the femoral shaft fracture. The usual combination is parallel screws in the femoral neck and a retrograde femoral rod for the fractured femur. Pipkin type II fracture is fracture of the femoral head, dislocation of the hip, and fracture of the femoral neck. Try to avoid reduction of the hip dislocation by closed means (especially in the young patients). You may want to do open reduction of the hip dislocation especially if the femoral neck fracture is not displaced. Stress fracture is more common in female athletes. It can be tension fractures. Fracture or callus is present on the superior aspect of the femoral neck. Adult bone is weak in tension, so stress fracture of the femoral neck needs to be fixed. This should be an emergency operation before the fracture displaces. With compression fractures, the compression or callus is present on the inferior aspect of the femoral neck. Some people believe that if the compression fracture is less than 50% across the neck, then the fracture could be stable and you can do protected crutch ambulation. If the compression fracture is more than 50% across the neck, then the fracture is unstable and you will do ORIF. Some surgeons fix all stress fracture of the femoral neck. A female runner with groin pain will rule out stress fracture. Get an MRI, and you will probably have to fix the fracture. Femoral neck fractures can also occur due to insufficiency fracture. This occurs due to weak bone because of osteoporosis or osteopenia. The patient will have groin pain, pain with axial compression, and the x-ray may be normal (MRI is helpful in diagnosing insufficiency fracture).

Causes of Hip Pain

Pain can arise from the structures that are within the hip joint or from the structures surrounding the hip joint. The most important thing is to ask the patient to locate the site of pain. ask the patient to point at the site of pain. When the patient states that their hip hurts, it doesn’t mean that the pain is coming from the hip joint itself, so ask the patient to point at the site of the pain. The pain can arise from structures that are within the hip joint or from structures surrounding the hip. The hip joint is a weight bearing joint. The joint consists of two main parts: femoral head (ball) and acetabulum (socket). The hip pain can be anterior hip pain (deep groin pain). The pain can be lateral hip pain. the pain can be posterior hip pain. The pain can be far posterior hip pain, coming from the sacroiliac joint and the lower spine. Anterior hip pain is usually deep within the groin, and it can result due to arthritis of the hip. Conservative treatment is physical therapy, anti-inflammatory medication, possible injections, and surgery is done in late cases, usually by total hip replacement. It is usually diagnosed by clinical examination with a provocative test of flexion, adduction, and internal rotation. The diagnosis is confirmed by an MRI arthrogram. Conservative treatment is therapy, anti-inflammatory medication, and injections. Surgical treatment provides good result and is usually done by arthroscopic debridement or repair of the tear. Stress fracture is usually diagnosed by an MRI. The x-ray may be normal. Early diagnosis is important before the fracture displaces and gives a bad result. Treatment of avascular necrosis is usually surgical fixation of the fracture. Fixation of the fracture is usually performed utilizing screws. Femoral head replacement is done in rare, late cases. Avascular necrosis means death of a segment of the bone. When the blood supply of the femoral head is interrupted, a segment of the bone dies and becomes necrotic (femoral head will collapse). Treatment for early stages of AVN without collapse of the femoral head include decompression by drilling of this segment in the femoral head to bring a new blood supply to the area. Vascularized fibular graft may be used also. In severe cases with collapse of the femoral head (usually diagnosed by an x-ray), the treatment is usually total hp replacement. Treatment of an inflamed bursa is usually conservative treatment of physical therapy, anti-inflammatory medication, and injection. Surgical treatment by excision of the bursa is rarely done. In case of chronic, resilient trochanteric bursitis, try to get an MRI to exclude a tear of the abductor muscles of the hip (gluteus medius and gluteus minimus muscle tear). Posterior hip pain is usually due to piriformis syndrome. The sciatic nerve can be irritated from the piriformis syndrome. Treatment is usually physical therapy, stretching, anti-inflammatory medications, and injections. Surgical treatment is usually rare. It is the last resort. It includes release of the piriformis tendon and exploration of the sciatic nerve. It is done in cases that fail to improve with conservative treatment. Far posterior pain may come from the sacroiliac joint or from the lower spine conditions. Sacroiliac joint (SI) problems is a challenging diagnostic and treatment entity. There are a lot of clinical diagnostic examinations that can be used to diagnose sacroiliac joint (SI) problems such as the Faber test and others. However, injection of the SI joint is probably the method to diagnose pain originating from the SI joint. If there is improvement of the condition of the patient after injection of the SI Joint, then we will probably consider that the problem is in the SI joint. The SI joint problems are usually under estimated and are unappreciated. Lower spine conditions can cause referred pain to the buttock and hip area. In fact, symptoms of hip and lower spine conditions can overlap or both of them can coexist in the same patient. You have to separate pain from the hip from pain that comes from the spine.

Anatomy of the Upper Arm

The muscles on the front of the upper arm consist of three muscles- biceps brachii muscle, brachialis muscle, and coracobrachialis muscle. The biceps brachii muscle is a strong supinator of the forearm; it flexes the elbow joint, and the long head of the biceps stabilizes the shoulder joint. The brachialis muscle is the primary flexor of the elbow joint. The coracobrachialis functions as flexion and adduction of the shoulder. The musculocutaneous nerve arises from the lateral cord of the brachial plexus. It is the primary nerve supply to these three muscles. It is the primary nerve supply of the muscles of the anterior compartment of the upper arm. It supplies sensation to the lateral half of the forearm.  The triceps muscle is another muscle of the upper arm, but it is located on the back of the upper arm. The triceps muscle functions as the powerful extensor of the elbow joint. The muscle has three heads: long head, lateral head, medial head. It is innervated by the radial nerve from the posterior cord of the brachial plexus.

Osteocytes

By Nabil A Ebraheim MD & Aaron Poliak MD

Our skeleton has billions of osteocytes. Osteocytes make up roughly 90% of cells in the human skeleton. The osteocyte is different from the other two types of bone cells, osteoblasts and osteoclasts. How do osteocytes form? Osteoblasts produce osteoid, composed predominately of Type 1 Collagen, which in turn surrounds itself. The mature osteoblast gets trapped in the matrix that they produce and become enclosed in an area called the Lacunae. When they get trapped, they become osteocytes. Osteocytes have dendritic processes which allow them to communicate with one another. This communication occurs through canaliculi and gap junctions. Osteocytes help with the complex orchestra that is bone remodeling. Osteocytes are sensitive to different stimuli, especially mechanical. When one osteocyte experiences mechanical stress, it sends signals to nearby osteocytes through its dendrites to increase bone remodeling in these areas of maximal mechanical stress through the recruitment of osteoblasts and osteoclasts. Therefore, the osteocyte is a regulator of bone remodeling by controlling the osteoclasts and the osteoblasts. Hormonally, the osteocyte is stimulated by calcitonin, and it is inhibited by PTH (the osteoblast is stimulated by PTH). Another important feature of the osteocyte is its ability to regulate calcium and phosphate concentrations in the bone.