Sporhopaedics Mathys


Which symptoms are indicative of a tear of the anterior cruciate ligament?

Tearing of the anterior cruciate ligament can occasionally make a sound like the crack of a whip. Typical symptoms are knee swelling, bruising in the joint, pain and instability. As a reaction to the injury, the joint is often held slightly bent in a protective position.

How is a cruciate ligament tear diagnosed?

For the doctor, the so-called drawer test often provides the crucial indication of a rupture of the anterior cruciate ligament, together with the typical symptoms. This test is performed with the knee bent to determine whether the lower leg can be shifted forwards or backwards from the thigh, like a drawer. In a healthy knee, the intact cruciate ligaments limit this movement. X-rays are good at imaging bones; however, ligaments and soft tissues remain invisible. To be able to image softer tissues such as muscles, cartilage or the cruciate ligament, magnetic resonance tomography (MRI, CT) is needed. This examination method can also reveal associated injuries, such as injuries to the meniscus, the joint capsule or to other ligaments, which are not visible during X-ray examinations.

Does the Ligamys implant remain in the joint, or is it removed later?

As a rule, all components of the implant may be left in the joint without any problems. If desired, or if required clinically, the metal sleeve can be removed in an outpatient procedure after the cruciate ligament has grown back together. The resultant cavity can be filled with bone replacement material: This gives the bone the possibility of regenerating independently, closing the opening. The polyethylene thread is left; in general, it grows together with the regenerated cruciate ligament.

Which symptoms are indicative of a tear of the anterior cruciate ligament?

Tearing of the anterior cruciate ligament can occasionally make a sound like the crack of a whip. Typical symptoms are knee swelling, bruising in the joint, pain and instability. As a reaction to the injury, the joint is often held slightly bent in a protective position.

What are the consequences if a cruciate ligament rupture is not surgically repaired?

The cruciate ligaments ensure the stability of the knee joint during movements, and this function can to some extent also be provided by the knee joint muscles. Thus, a torn anterior cruciate ligament does not necessarily require surgery, however the stability may remain limited, which may result in an increased risk of subsequent injuries to the knee – such as a torn meniscus.

Can the Ligamys implant be felt in the tibia?

In most patients, the metal sleeve does not cause any significant impairment in the tibia (monobloc). In individual cases, a small bump on the anterior edge of the tibia underneath the knee joint can be felt. This is not problematic and is completely normal. However, if the monobloc is bothersome or in rare cases cause pain, it can be removed in an outpatient procedure.

What happens if the cruciate ligament does not grow back together, despite Ligamys?

As with any surgery, there is also a small risk in the case of the Ligamys procedure that it will not yield the desired successful result. In these cases, however, a conventional cruciate ligament replacement can be performed at a later point in time – without any restrictions.

What materials is the implant made of?

The implant components consist of materials that have been proven over the years in the field of orthopaedics. The thread is made of the synthetic material polyethylene, and the plate at the upper end is made of titanium. The sleeve for the tibia (monobloc) is made of medical implant-grade steel. In general, there are no allergic reactions to these materials. Patients who have a hypersensitivity (allergy) to certain metals should discuss this with the attending doctor.

Despite the Ligamys implant, can magnetic resonance imaging (MRI images) be taken later on?

Yes, later MRI examinations are possible under certain conditions (this is known as MR Conditional). More information about the limitations of Ligamys in an MRI environment is listed in the Instructions for Use under point 7.

What should be borne in mind in the case of Ligamys, in comparison to reconstruction using a donor tendon?

The biggest difference compared to reconstruction with a replacement tendon is that treatment with Ligamys should be performed until the 21st day after the cruciate ligament rupture, according to current recommendations. If the treatment does not achieve the desired success, a conventional cruciate ligament reconstruction with a graft can alternatively be performed.

Can a Ligamys implant also be used for ruptures of other ligaments (such as the collateral ligaments)?

Ligamys was specifically developed for the treatment of anterior cruciate ligament ruptures and is currently used only for this purpose. Since this ligament differs in its function and mechanical properties from all other ligaments of the body, Ligamys cannot be used for other ligaments.

Is the cruciate ligament sutured after the rupture?

No. The polyethylene thread of the Ligamys implant only aids in stabilising the injured knee. However, to create the mechanical preconditions for the cruciate ligament to grow together, the ruptured ends are not sutured. They are only brought together using an auxiliary suture so that the ligament can grow together at the right location.

What happens during the surgery?

The surgery is performed during an arthroscopy procedure using a small camera and miniature instruments which are inserted into the joint through two or three small access points. The procedure takes about 45 minutes and can be performed in regional anaesthesia of the lower half of the body (spinal anaesthesia), or in general anaesthesia. The length of the inpatient stay depends on the scope of the injury, any concomitant injuries as well as the regeneration process, and will be determined by the attending doctor. Normally, patients only spend two days or less in the hospital.

How large are the knee scars?

Only small incisions are needed for the arthroscopic Ligamys implantation, in order to introduce the surgical instruments into the joint. The two access incisions on the knee joint are each about 1.5 cm long, and an approximately 4 cm long incision is needed to implant the metal sleeve in the lower leg (monobloc). In most patients, the scars are unobtrusive after healing and hardly visible.

How long does it take for the cruciate ligament to grow back together?

The treatment with Ligamys promotes biological self-healing of the ruptured cruciate ligament and is thus a natural process whose duration differs from person to person. Usually within 6 months, the ligament grows together to an extent such that gentler forms of non-contact sports can be performed.

Which hospital or which doctor will implant Ligamys?

The Ligamys implant may be used only by doctors who have completed the corresponding training. Thus, ruptures of the anterior cruciate ligament can be treated with the Ligamys implant only at select hospitals; however, the number of approved hospitals is continuously increasing. The current list of surgical centres can be found under "Who implants Ligamys?" ((Link))

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These web pages contain general information about the Ligamys implant, crucial ligament injuries and its treatments as well as the manufacturing company Mathys Ltd Bettlach. They do not contain specialist advice, recommendations, instructions or binding offers. If you have questions regarding Ligamys, please contact us directly under info@ligamys.com

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