Comparison between Lengthening over Nails (LON) Method and Holyfix Method in Limb Lengthening Surgery
“LON” stands for” lengthening over nails “, which literally means that the bones are distracted or lengthened with an internal nail; however the bones are lengthened using a mono-lateral type external fixator device; similar to the one used in the Holyfix method.
The main difference between the LON method and Holyfix is the presence of the internal intramedullary nails over which the bones are lengthened over. This provides some important advantages over other fully external methods like Holyfix or Illizarov; that the patients are enabled to have the external fixators removed much earlier than with fully external methods. Usually, with LON, external devices can be removed approx. 3-4 months, after the surgery, while in Holyfix method these devices can be removed only after full consolidation of bones (which takes around 9-12 months).
In LON method, the intramedullary nails stay inside the bone cavity until, the bones fully consolidate, heal, and recovery; which can usually happen, approximately, after 1-1.5 years of the surgery. After which the patient’s bones should have fully strengthened, the internal nails can also be removed by a minor surgical operation.
What is LON Method?
Lengthening over Nails (LON) is relatively new technique that combines external fixator distraction osteosynthesis with the convenience of intramedullary nail.
The Lon method, also known as external fixator combined with intramedullary nail, is a holding system attached by the skin. This method is used for broken bones and lengthening surgery.
The external device can be an Ilizarov fixator, a monolateral (rod-like) fixator, or any other device developed by some doctor anywhere, it is mainly up to the preference of the surgeon who practices limb lengthening.
An Intramedullary Nail or Rod, is generally a metallic nail type rod device which is surgically embedded within the bone cavity, during a Limb Lengthening Surgery by LON Methodology.
How does a LON method surgery work?
During the Limb Lengthening Surgery by LON Methodology, the external fixator is attached to the bone through the skin. The intramedullary nail (intramedullary screws) is inserted on the femur either through a small skin incision above the hip or below the kneecap. To extend the lower leg, the intramedullary nail is also inserted below the kneecap.
The extension is done with the external fixator, the patient extends with a special screw every day by 1 mm to – 1.5 mm every 6 hours (4×6 hours), with the screw on the outside of the external fixator by 0.25 mm – to 0 .5 mm, so that at the end of the day 1 to 1.5 mm can be reached.
With the external fixator, the thigh and lower leg bones are gently lengthened.
The surgery lasts on average between 3 to 5 hours under general anesthesia.
Once the LON apparatus is surgically attached to the patient’s legs; soon after 3-5 days of post-surgery hospitalization, the lengthening period begins at the hospital, whereby the external fixator is elongated or distracted by 1 mm per day, allowing the patient’s bone to separate, with the intramedullary nail inside their bones.
The biggest advantage of having an intramedullary nail in this method is that it helps in correcting any angular bone deformity, during this lengthening phase, as well. Within 60 to 80 days of lengthening, elongation of the bone is stopped, and we let the bone start to heal between the gaps created; and once there is ample weight-bearing bone consolidation, usually 30 to 45 days after the lengthening has been stopped; the doctors could remove the external fixator devices. This allows for quicker recovery time, in comparison to purely external fixator methods; as after this stage the patient’s bones would generally take around 5-6 months to fully heal. Thus, allowing the whole process to complete in 8 to 9 months; which in reality is as fast as any internal method; this is why LON is one of the most preferred methods of Limb Lengthening surgery by our patients worldwide.
What is Holyfix Method?
The “Holyfix” method is a monolateral rod type method that has been used in success since 1997. This method involves limb lengthening to be achieved with an external fixator without any internal bone support. Monolateral external fixators are attached by pins to the patient’s legs. The nails are attached to the nearest and safest area, especially not near any vein and nerve. The chances of open wound infection is very small.
Holyfix apparatus is made of a special, aluminum and titanium alloy, thus lighter in weight and is MRI and radiology compatible. Hence, making this biomechanical system extremely stable and safe; allowing the patient to walk during the treatment phase. This device makes the distraction (bone lengthening) process very practical and easy, allowing the patient to perform extensions on their own. In addition, Holyfix apparatus has such a superior design that it allows for accelerated bone formation and transfers the burden from the bone without any shortening (Dynamization).
During the procedure
Arm or leg extensions:
If the length of bone is extended to 5 cm, one level, it is extended over 5 cm, two-level cuts are surgically made. Two or three nails are applied to both sides of the area. This is mainly dependent on the body weight (BMI) of the patient. Henceforth, a suitable “HolyFix” fixator is prepared and applied.
During the surgery, an incision is made on the skin section about 3 to 4 cm. Monolateral external fixators are attached by pins to the patient’s legs. The nails are attached to the nearest and safest area, especially not near any vein and nerve. Single-zone single arm-leg lengthening surgery takes an average of 40 minutes; arm-leg lengthening takes about 60 minutes. The operation is performed under either general anesthesia or spinal anesthesia.
Monolateral External Fixators
Monolateral external fixators have a straight bar that is placed on one side of the arm, leg or foot. It is connected to the bone by screws that are often coated with hydroxyapatite to improve the screws’ “hold” in the bone and prevent loosening. The patient (or family member) may need to adjust the device several times a day by turning knobs.
Height lengthening:
Height lengthening is a process where both legs are extended. Whereby, both the legs are lengthened at the same time, thus the patient’s height is increased, simultaneously. Limb Lengthening Surgery by Holyfix Methodology, generally, take about 90 minutes for a single level (up to 5 cm), 2-2.5 hours for a double level (up to 10 cm).
Lengthening Period:
Normally, this process of lengthening starts at the hospital. The lengthening is a total of 1 mm per day in four equal parts (4 × 0.25 mm) at each lengthening level.
About Iranian Surgery
Iranian surgery is an online medical tourism platform where you can find the best orthopedic Surgeons in Iran. The price of Limb lengthening Surgery by LON and HolyFix method in Iran can vary according to each individual’s case and will be determined based on photos and an in-person assessment with the doctor.
For more information about the cost of Limb Lengthening Surgery by LON and HolyFix method in Iran and to schedule an appointment in advance, you can contact Iranian Surgery consultants via WhatsApp number +98 901 929 0946. This service is completely free.