

KNEE SURGERY

	KNEE REPLACEMENT ARTHROSCOPIC PROCEDURES KNEE ANATOMY AND FUNCTION
KNEE CONDITIONS

	PATELLAR TENDONITIS CHONDROMALACIA PATELLA RUNNERS KNEE BAKER'S CYST BURSITIS ARTHRITIS OSTEOARTHRITIS PLICA SYNDROME OSGOOD-SCHLATTER DISEASE OSTEOCHONDRITIS (OCD) PATELLOFEMORAL DISORDERS
KNEE INJURIES

	ANTERIOR CRUCIATE LIGAMENT INJURY (ACL) ARTICULAR CARTILAGE LESIONS LATERAL COLLATERAL LIGAMENT INJURY (LCL) MEDIAL COLLATERAL LIGAMENT INJURY (MCL) PATELLAR TENDON RUPTURE POSTERIOR CRUCIATE LIGAMENT INJURY (PCL) TORN MENISCUS (Cartilage) FRACTURES & DISLOCATIONS
PATIENT RESOURCES

	SPORTS RELATED KNEE INJURIES BEFORE KNEE SURGERY KNEE SURGERY RECOVERY Insurance Carriers

Knee Fractures and Dislocations

The lower end of the femur bone is broad and forms two curved structures that are called condyles. The one located on the inner side is called medial condyle and the one on the outer side is called lateral condyle. In the front the condyles are united with each other. Behind they are separated by a space called the intercondylar notch.

The supracondylar area of the femur is the part that lies between the condyles and the shaft of the femur. Intercondylar area is the part between the two condyles.

In young adults these fractures result from high energy injuries such as road traffic accidents. In the elderly they occur following a minor fall with the knee joint flexed in weak osteoporotic bone.

Symptoms include the following

Patient will give a history of a fall or accident.
Severe pain and swelling will be present.
Deformity is seen in the thigh or knee.
Inability to lift the leg and inability to walk.
The ankle and the toes can be moved freely unless there is a neuro-vascular injury along with the fracture.

In elderly people there may not be much pain and swelling. History of injury may also be vague. Inability to walk and lift the leg should alert us to the possibility of a fracture.

Diagnosis of the fracture can be easily made with x rays of the knee joint taken in two planes. At times it is difficult to understand the fracture pattern on x rays. In such conditions if is advisable to get a CT scan with three dimensional reconstruction of the fractured knee. This greatly helps in planning of definitive treatment.

Fractures of the knee include:

The Patella
Femoral Condyles
Tibial Eminence
Tibial Tuberosity
Tibial Plateau.

Fractures of the knee can result in neurovascular compromise or compartment syndrome. Soft-tissue infection or osteomyelitis may occur with open fractures. Other complications include nonunion, delayed union, osteoarthritis, avascular necrosis, fat embolism, and thrombophlebitis. See also separate article Complications from Fractures.

Patellar Fractures

May follow a direct blow to the patella, sudden forceful knee flexion or contraction of the quadriceps muscle.
Presents with pain, swelling and difficulty with extending the knee.
Displaced, transverse fractures result in an inability to straight leg raise, which can also be caused by rupture of a quadriceps tendon or a patellar tendon.
X-rays: may be difficult to interpret because the patella overlies the distal femur and subtle fractures may be obscured. In a bipartite patella, the accessory bone is usually in the upper, lateral part of the patella.

Dislocation of the patella

The patella usually dislocates laterally.
This is most common in adolescents and more common in girls.
It is usually caused by a twisting injury or a direct blow, with the knee in slight flexion.
There may be an associated osteochondral fracture.
The dislocation may reduce spontaneously and there may be a history of recurrent dislocation.
Assessment:
- Presents with knee pain and the knee is held in flexion with lateral displacement of the patella.
- X-rays: usually not required prior to reduction of the dislocation.

Dislocation of the knee

Knee dislocations are uncommon. A knee dislocation is defined as complete displacement of the tibia with respect to the femur, with disruption of 3 or more of the stabilizing ligaments. Small avulsion fractures from the ligaments and capsular insertions may be present.

This is rare and indicates severe disruption of the cruciate and collateral ligaments and other soft tissues of the knee.
There is usually gross deformity of the knee with swelling and immobility, but up to 50% of knee dislocations are reduced by the time of arrival at hospital and may not be obvious.
There may be fractures of the tibial spine or the tip of the fibula due to ligament avulsion.
There may also be an injury to the popliteal artery and nerve (distal pulses and sensation should be checked and monitored). Popliteal artery damage may not be initially evident but may develop some hours later.