The patient history should investigate multiple aspects of the injury, including pain location and the mechanism of injury. The patient must describe the injury's event and the force directed toward the ankle along with the intensity of this force. Higher levels of force should raise the suspicion of more complications. The foot and ankle position during injury also requires analysis because it will help to classify the fracture according to the Lauge-Hansen classification system. Past medical history, such as diabetes, peripheral vascular disease, and metabolic bone disease, may affect treatment plans. Chronic medications as corticosteroids can cause osteoporosis. So, it is necessary to ask about medication history. 

On physical examination, it is essential to examine the normal ankle before the injured one to detect any differences between the two ankles and set a baseline to elucidate any deviation from the normal. It is also important to examine the knee, fibula, tibia, ankle, and foot and look for any signs of fracture like swelling, redness, hematoma formation, and lateral or medial tenderness malleolus or the proximal head of the fibula. The inability to bear weight on the injured foot is indicative of a fracture, and palpation can identify the fracture's exact location.

The clinician must ensure that the foot and ankle's neurovascular state is intact, including examining the sural artery, saphenous vein, and superficial peroneal nerve, and by assessing the motor function, sensation, capillary refill time, and pulses in the site of the injury. Examine both the active and passive range of motion of the joint, as well as weight-bearing status. Also, assess if there are any signs of open wounds or compartment syndrome.[1][7][11]

According to the Ottawa Ankle Rules, the clinician should not order ankle radiographs unless there is pain or tenderness in the ankle malleoli along with one of the following:

• The presence of tenderness at the tip of lateral or medial malleolus within or 6 cm above these structures
• Patients should not be able to bear their weight after the injury weight-bearing.

Radiological Features

Plain-film Radiographs:

Ankle X-ray is the best initial investigation, requiring three views:

• Anterior-posterior view: assesses the soft tissue swelling and checks if there any subtle fractures.
• Mortise view: this view is is done by putting the foot in 15 to 20 degrees of internal rotation. It evaluates the talus positioning and the syndesmosis widening.
• Lateral view: serves to assess fractures in the lateral view and for determining any effusion in ankle joint

Sometimes the tenderness is present in the proximal leg in addition to the widening of the syndesmosis, without obvious fracture in the ankle; however, there is a fracture in the proximal fibula. It provides a clue to the rupture of the syndesmosis. This presentation calls for an image for the tibia and fibula to diagnose this injury called Maisonneuve fracture, which is a spiral fracture in the proximal third of the fibula.

Usually, weight-bearing films, if possible, are the best option to diagnose syndesmotic injuries.

CT:

• CT is mostly for potential posterior malleolar fractures and to give an idea about the degree of impact. 

MRI:

• MRI is only indicated to assess soft tissues, i.e., cartilage or ligament injuries.  

Ultrasound:

• Ultrasound is also sometimes useful for ligament assessment, but the results are user-dependent. [1][7][11]

In treatment, assessment of the patient and the injury should proceed in a systematic approach according to ATLS guidelines. The primary survey should come first, ruling out any life-threatening injuries. Then, the examiner can manage the ankle fracture, first checking if there is any neurovascular damage that needs an urgent ankle reduction to regain the foot's vascularity and to avoid long-term sequence. A skin integrity examination is essential because open fractures could be treated primarily by external fixators. Open fractures can lead to delayed union, infection, and skin necrosis. 

Most bimalleolar fractures are unstable fractures and require treatment with open reduction internal fixation (ORIF). The management plan can be for either operative or non-operative treatment.

Non-operative 

Uses a below-knee cast for six weeks or a total contact cast for three months in patients with diabetes; indicated if the fracture is stable or when the patient cannot tolerate surgical fixation. It needs repeat ankle X-rays in a week to check for any displacement. Also, patients should be on thromboprophylaxis. 

Operative

ORIF is indicated when the fracture is unstable, such as in a talar shift. The technique is by fibula fixation using plates and screws (lateral malleolus) and medial malleolus fixation using cannulated screws or tension band wiring or plate over medial malleolus in certain types of medial malleolus fractures (Lauge-Hansen supination-adduction fracture pattern). Also, if there is syndesmotic injury is, syndesmotic screws should be inserted (there are some intraoperative tests to check syndesmosis integrity, one of them called the Cotton test). If the posterior malleolus fracture is more than 25%, a CT scan is necessary, and it requires posterior fixation using cannulated screws or, in some situations, plating.

In the two options, thromboprophylaxis is necessary until the patient achieves full weight bearing to avoid the risk factor of DVT.[2][8][6][9][1]

Previously, surgeons stated that a reduction of the lateral malleolus was the critical element in treating ankle fractures. Today it is accepted that the deep deltoid ligament is the primary ankle stabilizer preventing lateral talar shift and external rotation of the talus.[12]

• Ankle sprain
• Osteoarthritis
• Osteosarcoma
• Osteomyelitis
• Achilles rupture
• Septic arthritis
• Tendon dislocation
• Rheumatoid arthritis
• Osteoid osteoma
• Charcot joint
• Pathologic fracture
• Ewing sarcoma
• Gout

The bimalleolar fracture can have a poor prognosis, depending on the patient and operation, like the elderly, persons with diabetes, and especially those with comorbidities. In general, full weight-bearing takes time and is usually only possible at 12 to 16 weeks, but it generally takes up to 6 months to achieve full weight-bearing with final functional recovery. With operative intervention, the mortality at one year after the surgery is 12% in patients older than 65 years, increasing to 50% for patients over 95 years old.[2][1][6][13]

The complication includes: wound infection, wound hematoma, delay of wound healing, dislocation, arthrosis, inadequate reduction, complex regional pain syndrome, compartment syndrome, impingement syndrome, limited range of motion, malunion, malunion, and Charcot arthropathy mainly in diabetic patients. The long-term complications include deformity, infection, ulceration, ankle osteoarthritis, and amputation. Until the patient reaches full weight-bearing, they must take thromboprophylaxis to prevent the development of DVT or pulmonary embolism.[1][9]

In patients with bimalleolar ankle fractures, since many patients are under surgical management, it is essential to educate them about the importance of postoperative physiotherapy that results in significant differences in treatment and weight-bearing status. Any delay in the union or any struggle to achieve weight-bearing status rates as a red flag, and the patient must be aware of this point. Patients must closely adhere to postoperative instructions and therapy to achieve optimal outcomes.

Bimalleolar ankle fracture is considered an unstable fracture, and the orthopedic team should be responsible for its management. This fracture needs communication with the orthopedic surgeon to enhance and to improve patient outcomes. The physiotherapist's essential role is to help the patient physical health, muscle strength, and weight-bearing abilities after the surgery. The emergency team should perform emergency fracture reduction. After the surgery, all interprofessional team members should follow up with the patient to ensure a full recovery. This team includes:

• Orthopedic team
• Physiotherapy team

At home, the patient must be given thromboprophylaxis prescriptions and equipment like (walker boots, crutches, canes, etc.), and ensure that there is someone at home to help the patient till full recovery.