A bone healing in a wrong position and direction is called a malunion. In cases of malunions, a broken bone starts to heal in different positions – such as, the bone may be rotated, crooked or becomes shorter than its normal length. A malunion fracture can also have a combination of all these deformities together.
Malunions may or may not impair daily activities – and therefore, don’t need any treatment. However, malunions occurring in the lower limbs due to fractures can often result in substantial functional impairment. These malunions look aesthetically and cosmetically displeasing – apart from causing pain and limp.
Treatment mostly involves a surgical correction with an aim to correct alignment of the fractured bone and improve function in the affected leg.
Foot problems (rotational abnormality) – The foot turns inward or outward
Limb length discrepancy – the leg is longer or shorter than the other leg
The inability to fully extend or straighten the leg.
In comminuted fractures the bone breaks into many pieces. It becomes difficult to properly align those pieces and put them back. Therefore, in this type of fractures, the bone most likely to heal in an abnormal position and alignment. This may happen even after an appropriate treatment.
In some cases, malunion fractures can also result after casting and surgical fixation. In these cases, the broken bone shifts in a different position during the healing process.
These fractures can alter the position of bones during the healing process and cause unwanted symptoms – such as limp while walking and the foot turning in or out. In some cases, foot pain, ankle pain and knee pain can also occur due to malunions. This is mostly due to malunions changing or altering a person’s walking style and mechanics putting pressure on the other joints of the body.
An orthopedic doctor specializing in the management of malunions carefully and comprehensively examine the patient. The doctor deeply examines the previously broken bone. And then, asks a few questions to know when was the bone broken and what type of treatment was done to fix it in the past. The doctor, next checks the affected limb for a variety of motions in the joint. Symmetry is also important here as the doctor examines the patient’s normal size for comparison.
The doctor asks the person to move to keenly observe how the person moves (The way the affected person walk – gait). A lower limb malunion causes altered gait – where in the person limps or points his feet inwards or outwards. The doctor also measures any discrepancy in the length of the leg.
The doctor may order X-rays and CT scans as well to see and learn more about the nature of the malunions and also to get precise measurement of discrepancy in the length.
An orthopedic doctor provides treatment for a malunion in the lower limb based on the type of affected bone; patients symptoms; complications of malunion; impact of malunion on daily functions and mobility and severity of the condition.
The doctor addresses the malunion that is causing length discrepancy by recommending a shoe lift (either inside or outside of the shoe). This will help in improving length, improving gait and reducing back pain. This is quite economical and simple treatment.
Some cases where the leg position is out of sorts without any painful symptoms, the doctor suggests bracing for providing additional support. Braces will help in pulling the affected leg in a straight position and thus improving walking ability.
An orthopedic doctor specializing in the malunion fractures surgery recommends surgery to correct the malunion and to improve mobility, discomfort and pain.
Osteotomy – In this type of surgery, the bone is cut or rebroken at the original fracture site. It is then held in correct anatomical alignment and position using either internal or external fixations – based on the severity of the fracture and its location.
There are two types of fixations – internal fixation and external fixation
Internal fixation – The orthopedic doctor uses plates and screws and attach them outside of the bone or places a rod in the center of the bone.
External fixation – The orthopedic doctor uses a metal frame and positions it outside the leg and then attaches it to the bone with wires and pins.
Distraction osteogenesis – The procedure involves lengthening the limb using internal lengthening rods or external frame. With this procedure, the orthopedic doctor addresses the issue of shortened bone with a significant length discrepancy caused by malunion. Distraction osteogenesis helps in equalizing the limb length over a period of time and thus eliminating the limp caused by a short leg.
Post-surgical pain is common, but the orthopedic doctor and pain management expert ensure to minimize pain as much as possible. The doctor prescribes pain relievers including nonsteroidal anti-inflammatory drugs (NSAIDs), opioids and local anesthetics.
after the procedure, the orthopedic doctor immobilizes the leg in a splint or cast for some period of time. The doctor instructs the patient not to bear weight until their bones become strong and heal properly. To regain muscles strength, a range of motion and walking ability, the doctor will suggest physiotherapy for several weeks.
During the follow up care, the doctor monitors the alignment of the bone and healing process with the help of X-rays. This is to ensure that the bone is healing with apt alignment in the proper position.