Hip Fractures Mechanism of Injury

 

Low energy fracture occurs in the elderly from a fall onto the greater trochanter. The young will try to protect themselves by falling on the wrist. High energy fractures can occur in both the young or the elderly  form either a fall or a car accident.

Femoral Neck Fracture Anatomy

 

The neck shift angle is approximately 130 degrees. Anteversion is approximately 10 degrees. The calcar is an area of stress transfer. It is a posteromedial dense plate of bone. It forms an internal strut within the inferior part of the femoral neck and the intertrochanteric area. No periosteum in the femoral neck and no abundant callus. The fracture heals by endosteal proliferation. The medial femoral circumflex artery is the most important blood supply to the femoral head. In young patients, injury is usually high energy that may lead to avascular necrosis. Some believe that surgery should be urgent in the young patient in order to decompress the compressed vessels. The more displaced the fracture and the more vertical the fracture, then the more likely that the risk of complications will occur including disruption of the retinacular vessels, avascular necrosis, and nonunion. Femoral neck reduction should be anatomic, either by closed technique or open technique (if closed reduction technique fails).

Bipartite Patella

 

Bipartite patella is a failure of the ossification centers of the patella to fuse. Common types of bipartite patella include inferior pole, lateral margin, and superolateral pole. The accessory ossification center at the superolateral pole remains unfused. In the cases of bipartite patella, you can see that the patella has two parts: the smaller part is rounded and usually located laterally. It can be confused with a fracture. The superolateral pole is the most common type (occurs in about 75% of patients). Try to get an x-ray of the other knee (it is bilateral in about 50% of the time). Skyline view x-ray with a squatting position (weight-bearing) may show displacement and increased separation of the fragment. The bipartite patella is usually asymptomatic, and it is usually an incidental finding on the x-ray. It may cause symptoms that mimic those of a fracture. Minor trauma or injury can cause the fibrous tissue between the two segments to become inflamed and irritated. Localized tenderness over the separated fragments, usually the superolateral part of the patella. The most common presentation is pain at the area of the separated fragments, especially during or after heavy physical activity or sports. It is usually asymptomatic and does not require treatment or surgery. In general, the most common error with bipartite patella is mistaking the condition for a fracture and fixing it (the patient really does not need surgery). Treatment is usually reassurance and observation, rest, knee immobilizer, physical therapy, and nonsteroidal anti-inflammatory medication (NSAID). Nonoperative treatment should be done for at least 6 months. These patients will improve without surgery. Surgery is rare, and it is excision of the fragment if the fragment is small. If the fragment is large, painful, and conservative treatment fails, then you can do lateral release of the retinaculum to reduce the traction force on the unfused, smaller fragment. Internal fixation and possible bone graft is rarely done if the fragment is large and painful.

Hip Fractures History Exam Evaluation of Patients

 

Obtain adequate history from the patient such as any syncopal episodes and loss of consciousness. The preinjury ambulatory status may determine the treatment selected for the patient. Falls and low sodium will increase the risk of hip fractures. Check for comorbidities. The number of comorbidities is directly related to 1-year mortality rate. Patients with 4 or more comorbidities are reported to have a higher 1-year mortality rate than patients with 3 comorbidities or less. Position of the leg is usually shortening and external rotation. You will be able to tell which hip is broken by looking at the feet of the patient. If the leg is shortened and externally rotated, then this is the broken hip. AP view and cross-table lateral view. In cross-table lateral view, you move the uninjured hip away. Cross-table lateral view is better than frog leg lateral view. Consider doing traction-internal view if the fracture is occult or comminuted. Check for hip arthritis and pathological fracture. If you have a comminuted femoral shaft fracture, you may look for an associated femoral neck fracture. In patients with femoral shaft fracture, the rate of associated femoral neck fracture is precisely undetermined, however it is approximately 5%, and the fracture may be overlooked in about 30% of the time. Normal x-rays of the hip do not mean that the patient with hip pain does not have a hip fracture. 8% of the patients may have an occult hip fracture. It may be important to get a CT scan of the neck of the femur when you have a comminuted femoral shaft fracture. This will help to diagnose an occult femoral neck fracture. You may see the fracture in abdomen/pelvic CT scan cuts, usually before surgery. Good for occult and stress fractures (if the patient cannot bear weight- get an MRI). If there is contraindication for an MRI, get a CT scan or bone scan. Bone scan increases sensitivity by waiting up to 72 hours after the injury. Deep vein thrombosis (DVT) can occur in about 80% of patients. Patients will need chemical and mechanical prophylaxis. The duration and the type of prophylaxis is not determined (no unanimity). Get the patient out of bed and allow weight-bearing as tolerated. The patient will autoregulate their ambulation. Preoperative cognitive impairment will lead to a higher incidence of delirium in patients with hip fractures. Delirium and time of surgery affected the length of stay in the hospital. Most patients with hip fractures between the ages of 50-80 years old were able to regain their mobility and independence. If the patient is older than 80 years old, the patient was able to regain their independence, but not their mobility with 70% of these patients requiring a walking aid at 12 months. The factors associated with the increased ability to ambulate and to live independently 1 year after surgery for femoral neck fracture are patients age 50-80 years old, ASA class 1, and pre-fracture independence. Some patients may delay coming to the hospital. They may have been lying on the floor for many hours or even days. Check the patient for DVT, ulcers, dehydration, and malnutrition (the patient may be very sick). May need comedical management with the medical team. Early surgery (within 48 hours) is associated with a decreased one-year mortality. Expedited definitive surgery of less than 24 hours will reduce the mortality rate at 30 days and at 1 year. A delay of more than 24 hours of surgery significantly increased the incidence of 30 day mortality, and 1 year mortality, as well as increased incidence of pulmonary embolism, myocardial infarction and pneumonia. If the patient has ASA 3 and ASA 4, this will increase the mortality rate for the patient (means that the patient’s condition is medically complicated and the patient is high risk). Types of ASA is classification of American Society of Anesthesiologists. ASA 1 is a lot better than ASA 4. In younger trauma patients, the femoral neck fracture should be dealt with urgently and after the overall condition of the patient is thoroughly evaluated to exclude other injuries. Early surgery may decrease the incidence of osteonecrosis.