Knee surgeon

Anterior cruciate ligament


The anterior cruciate ligament or ACL is one of the four major ligaments of the knee and is fundamental to maintaining stability. Injury to the anterior cruciate ligament is one of the most common knee injuries. It usually needs surgery to rebuild it and to be able to restore normal joint function.

About half of the injuries occur in combination with injuries to the menisci, cartilage or other ligaments. In addition to providing stability to the knee, the ACL protects the meniscus and the cartilage. Therefore, it is common for ACL injuries that are left untreated to lead to injury of these structures. In turn, this will lead to the accelerated and early development of osteoarthritis.


Anterior cruciate ligament surgery requires a thorough knowledge of the anatomy of its insertions as well as of the other ligaments and structures of the knee.

During his career as an anatomist and further development as a surgeon, Dr. Gelber has gained extensive knowledge in this field. It gives him a unique expertise when assessing injuries and reconstructing them as closely as possible to their prior natural state. The precise location of the tunnels is the most important aspect of ACL surgery. It is so much so that placement only millimeters off their optimum position is the main cause of ACL reconstruction failure.

In this context, ACL surgery has evolved dramatically in recent years. Not long ago and even in many places still today, the ligament is reconstructed with a central upright graft. This has led to continued rotational instability, which is most disabling and harmful to the patient. It has been shown that the best way to reconstruct the ligament is by reproducing its previous anatomy as this best restores its proper function in comparison to these previous techniques. Dr. Gelber has been a pioneer in Spain in the introduction of this technique and its variants of selective or partial reconstruction of the ligament. There are multiple scientific studies that Dr. Gelber has contributed to in this field of surgery. Although the ligament is functionally divided into two bundles, it has been demonstrated that it is not necessary to individually reconstruct each one in the complete tear. Different is the situation of partial ACL tears in which only one of the bundles is damaged. In these cases, treatment requires precision and experience as it is vitally important that the healthy bundle remains intact without injury during surgery while the damaged bundle is being reconstructed.

Anterior cruciate ligament surgery requires a thorough knowledge of the anatomy of its insertions as well as of the other ligaments and structures of the knee.


Hamstring tendons

Already in the operating room, Dr. Gelber uses different types of grafts for the reconstruction of the ligament, being in the vast majority of cases obtained from the patient himself. An alternative is the use of the hamstring tendons, which allow their extraction through a small 2 cm incision on the inside of the knee.

This results in less post-operative pain and better cosmetic results, as well as unbeatable clinical and sporting results.

Quadriceps tendon

Another tendon frequently used by Dr. Gelber is the quadriceps tendon. This alternative is most commonly indicated in revision surgery for re-ruptured ACL grafts.

Anterolateral reinforcement technique

Another field where Dr. Gelber is a world leader is in the so-called anterolateral knee reinforcement technique. It has been widely shown that in patients with more functional demands, such as athletes and those under 25 years of age, strengthening the anterolateral area of ​​the knee with an anterolateral tenodesis or anterolateral ligament reconstruction decreases more than 3 times the possibility that the reconstructed ACL will break This is because of the supporting or collaborating effect that this anterolateral technique has with the ACL. Currently, Dr. Gelber performs this combination in 70-80% of ACL reconstructions.

Lateral Extraarticular Tenodesis

Antero Lateral Ligament reconstruction

Other tendons

Another option is the patellar tendon, but due to its possible consequence of pain in postures such as squatting, it is an alternative that is not currently used as a first choice except in selected cases. Finally, tendons from tissue banks are a valid alternative, although due to their higher rate of breakage in very athletic people and the fact that their healing requires more time, they are left as an alternative in the case of multiple ligament injuries or in very old patients low functional demand. In short, each has its advantages and disadvantages, and the most appropriate one is used in each case. The philosophy of Dr. Gelber is to adapt himself to each specific case and not offer the same treatment for people who may have completely different conditions.


Before the surgery

Diagnostic tests

Dr. Gelber evaluates the knee using clinical tests, x-rays, and MRI to determine if the ACL is in fact injured. All this will help to determine if the ACL is intact, or if it has a partial injury or a complete injury. For diagnostic and therapeutic accuracy between different degrees of injury, precision and experience are required.

After surgery

The day after surgery and before leaving for home, the patient receives all the necessary information relative to postoperative care. The patient also leaves the hospital with an appointment for within 10 days or so to have the wound checked


The rehabilitation process is considered key to the reconstruction of the anterior cruciate ligament. It is imperative that the patient well understands the process to recover 100% of knee function. One of the most common complications after surgery of the anterior cruciate ligament is the loss of mobility, especially extension. This leads to limping, quadriceps muscle weakness and pain in the knee region. Many studies have shown that the worst time to perform the ACL surgery is when it is done with a swollen, painful and stiff knee. Therefore, this risk is minimized if surgery is delayed until the period of acute inflammation has passed, the inflammation has subsided a lot, complete or almost complete mobility is recovered and one can walk in an almost normal manner. 

General Phases

PHASE Ia (0-2 weeks)

Aims to eliminate the effusion, pain and to initiate muscle activation.

PHASE Ib (2-4 weeks)

Aims to eliminate the effusion, to achieve full extension and restore muscle control of the leg.

PHASE II (From week 5 until the objectives of the phase are achieved)

Aims to normalize walking, have mobility without pain and be able to stand on the operated leg without Crutches

PHASE III (From Phase II goals achievement until weeks 12-16)

the objective is to have control without pain with light and low impact exercise.

PHASE IV (from Phase III objectives achievement until week 24-40)

The aim is to have good neuromuscular control in specific low impact sports exercises

PHASE V: Return to any sports activity

Although there is the feeling that the knee is in optimal form many weeks before reaching this stage, the reconstructed ligament goes through a period of remodeling that even needs up to 2 years to complete. In any case, with the exception of cases of athletes who require an early return to their sports activity, it is advisable to avoid contact and pivoting activity until 8-10 months after surgery in cases where the sport is more casual type of.

Summary Rehabilitation Protocol


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