The posterior cruciate ligament or PCL is one of the 4 main ligaments that provide stability to the knee joint. Therefore, its damage is one of the most serious injuries to the knee joint. And the fairly high frequency of their occurrence (3-20% of cases of knee injuries) makes the problem highly relevant in modern orthopedics. Therefore, today there are already ways not only to restore the integrity of the PCL, but also to return it, and therefore the knee joint, to normal functionality as quickly as possible and with the utmost safety for the patient.
Causes of injuries
It's not easy to damage the posterior cruciate ligament. His mechanics are a powerful straight punch just below the knee. When does this happen? This often happens during a car accident, when during a head-on collision the driver’s leg is hit by the dashboard of the passenger compartment or a pedestrian is hit by the car’s bumper. In sports, the posterior ligament is most often injured by skiers when they collide with an obstacle on the descent. Ligament damage is often accompanied by injuries to the menisci and other nearby ligaments and structures. In such cases, treatment is carried out surgically, since the return of function is otherwise difficult. Arthroscopy is usually performed to reconstruct the ligament and restore other structures.
Diagnostics
Injuries to the posterior cruciate ligament are quite difficult to diagnose, especially in the acute period of injury. After all, the main sign of PCL damage is posterior instability of the knee joint, and pain and swelling prevent its detection. Therefore, it is not uncommon for patients with fresh knee injuries to be iced and given painkillers. If after this it is not possible to fully examine the knee joint, be sure to schedule a repeat examination in a week. After the end of the acute period, it is usually possible to carry out all the necessary examinations and diagnose damage to the PCL.
But if this is not done in time, secondary changes can occur in the knee, which will have an extremely undesirable effect on its condition and functioning. Therefore, it is important to consult an orthopedist as soon as possible after receiving a blow to the knee and undergo the recommended diagnostic procedures.
To assess the quality of functioning of the knee joint, an anamnesis is first collected, i.e., a survey of the patient. As part of this stage, the doctor finds out the specifics of the injury, which helps him determine both the possibility and the most likely mechanism of damage to the PCL, as well as assess the likelihood of injury to other structures.
After this, an orthopedic examination is carried out, during which the orthopedist palpates (feels) the knee, measures the circumference of the injured and healthy joint, assesses the amplitude of passive and active movements, and identifies signs of damage to the menisci or other intra-articular structures. To do this, he asks the patient to walk and also uses special diagnostic tests, in particular the posterior drawer test.
This is one of the most accurate methods for diagnosing PCL damage. It is carried out when the knee is bent at a right angle by determining the distance between the anterior surface of the central part of the epiphysis of the tibia and the condyles of the femur. If a displacement of more than 3-5 mm is detected, the test is considered positive. Moreover, the higher the obtained indicator, the higher the degree of the rear “drawer”. But this test is difficult to perform immediately after injury due to severe swelling of the knee and limited mobility.
In such situations, other tests may be used, in particular:
- Reverse Lachman test - the knee is fixed bent at an angle of 30°. If the tibia moves posteriorly relative to the femur, this is considered a sign of damage to the posterior cruciate ligament.
- Trillat test - considered positive when the tibia is displaced during flexion of the knee joint at an angle of 20°.
- Godfrey test - performed in a supine position with the legs bent at a right angle at the knee and hip joint. The doctor helps the patient maintain this position by holding his foot by the toes. If, under the influence of gravity, the tibia moves downward, the test is considered positive.
A number of other tests are also used to diagnose posterior cruciate ligament injuries. And to obtain the most accurate data on the nature and severity of the injury, since PCL injuries in less than half of the victims are isolated, the orthopedist refers the patient to:
- X-ray;
- Ultrasound;
- CT or MRI (performed in cases where the most accurate information about the state of intra-articular structures is required, and other methods did not provide the necessary data or an old injury and the development of complications are expected).
MRI is considered the gold standard for diagnosing PCL injuries.
Types of PCL ruptures
The first degree is characterized by incomplete rupture of the ligament (microtears, sprains). The pain syndrome is relieved in such cases by taking anti-inflammatory drugs. But specialist supervision is necessary; the lower limb is temporarily immobilized.
Second degree - rupture of the ligament without deformation of other structures. Here it is important to assess the consequences of such an injury and how the knee joint functions. The doctor makes the decision on surgical intervention after acute symptoms have resolved.
Third degree - complete rupture of the PCL in combination with damage to the anterior ligaments, meniscus and other tissues of the knee almost always causes instability, which becomes the reason for surgery to avoid complications.
Surgery on the ACL: types of plastic surgery, principle of execution
Any plastic procedure on the ACL is currently performed using minimally invasive arthroscopy. The arthroscopic session is performed in a closed manner under spinal anesthesia. The operation is a gentle type of high-precision surgery, so no damage is caused to soft tissues, nerves and vascular structures. In addition, manipulations are carried out exclusively on the affected area, and after the intervention no scars remain.
Surgery.
To reconstruct a damaged element, it is enough to make one 5-mm puncture for an optical probe, which has a built-in miniature video camera, and 1-2 additional accesses (no more than 8 mm in diameter). Through the auxiliary holes, the surgeon will use microsurgical instruments to reconstruct the damaged area. Visual control is provided by an arthroscope (endoscopic probe), which displays an image of the operated area on the monitor at 40-60x magnification. Surgery can be performed in several ways; we will consider them further.
Autotransplantation
In this case, a fragment of the patient's tendons taken from the thigh muscles is transplanted; sometimes material is taken from the ligaments or tendons of the patellar tendon. This does not affect the functionality of the donor site in any way. The reconstruction technique involves removing torn ligamentous structures and then introducing a prepared tendon graft in their place.
Material “collection” area.
The end sections of the tendon flap are threaded into the drilled canals of the femur and tibia and stretched to the required parameters, after which they are secured with biodegradable screws or mounted on special loops. After a few months, they completely grow into the bone without any problems. The technique has been well studied and has an impressive evidence base of effectiveness, therefore it is today the most used tactics for treating ACL, the “gold standard” of orthopedics and traumatology.
Allotransplantation
The donor of similar biological tissues in this case is not the patient, but a completely different person. It could be a close or distant relative, as well as a person who is not related in any way, and, after all, a corpse. Plastic surgery of a partial anterior cruciate ligament of the knee joint using an allograft is generally not used. And this is primarily due to the fact that the engraftment of a “non-native” substitute may not take place due to the so-called tissue incompatibility, and this greatly increases the likelihood of the body rejecting a foreign graft.
This technique can only be used in situations where the collection of the patient’s own tissues for transplantation is impossible for some reason, which is very rare. The principle of implantation and fixation of the allograft is the same as for autotransplantation.
Plastic surgery using the Legamis method
For reconstruction, a special implant is taken, which is a polyethylene thread and a hypoallergenic steel sleeve. The thread is fixed to the thigh bone, the sleeve is installed in the shin bone. A synthetic thread is pulled along the problematic ligament, connecting its torn parts, and then, under optimal tension, it is connected to the end of the sleeve.
In this way, reliable stabilization of the knee is achieved, thereby creating favorable conditions for natural healing of the tear. The method is advisable only for fresh injuries, no more than 3 weeks old. Today, this method is practiced in a few clinics in Europe, usually in medical centers in Germany. Actually, this technology was developed by German specialists.
Symptoms.
Quite characteristic symptoms for this type of pathology. Immediately after the injury, the patient presents the following complaints:
- Intense pain in the knee.
- Joint instability, loss of knee functionality.
- Feeling of dislocation.
- Instability, loss of knee functionality.
- Swelling of the knee due to hemarthrosis.
- Hemarthrosis (outflow of blood into the joint cavity due to damage to blood vessels).
- Limitation of movements.
- Hemorrhages are visible on the lower leg and in the popliteal region.
- Clicking sound when injured.
Treatment.
Conservative treatment of anterior cruciate ligament injuries usually does not produce good results in people returning to intense sports activities. Pain, swelling, and instability occur intermittently in 56% to 89% of athletes with ACL tears after conservative treatment.
It is impossible to stitch a torn anterior cruciate ligament; grafts are used to restore it, i.e. other tendons (patellar ligament autograft, hamstring autograft, allografts) or synthetic prostheses.
Surgery (arthroscopy) is performed if, after conservative treatment, the stability of the joint does not meet the requirements of physical activity. It is worth noting that the operation gives the best results against the background of good movements in the knee joint and strong muscles, which once again emphasizes the importance of the conservative stage of treatment. On average, anterior cruciate ligament reconstruction surgery for non-athletes is performed 6 months after a tear, but this does not mean that surgery is not necessary later. It happens that it is done 5-7 years after the injury. In principle, the operation can be performed at any time after the injury, with the exception of cases where severe arthrosis has developed in the knee joint due to a rupture of the anterior cruciate ligament and subsequent instability of the knee joint.
Diagnosis of PCL damage
A specialist can already guess the diagnosis based on the mechanism of injury. This is why it is so important not to miss the details when visiting a doctor in a clinic. Swelling and severe hemarthrosis often do not allow for a detailed examination. However, functional tests are indicative of this injury. Imaging methods, namely MRI (magnetic resonance imaging), CT (computed tomography), provide the clearest picture of the process. According to indications, diagnosis is carried out using arthroscopy - a minimally invasive operation that allows you to visualize the pathology from the inside.
Damage to the ligaments of the knee joint, diagnosis and treatment tactics
One of the most common pathologies of the knee joint is damage to the ligaments that fix the knee joint.
Knee ligament rupture is a type of musculoskeletal injury in which the ligaments of the knee joint are damaged. These ligaments, involved in fixing the tibia to the femur, are represented by the patellar ligament, the external and internal collateral ligaments, and the anterior and posterior cruciate ligaments.
With this type of injury, partial or complete rupture of the fibers of the ligament or its separation from the attachment site occurs. Often, such an injury can be obtained not only while playing sports, but also in a common accident.
Types of knee ligament rupture
Depending on which ligaments are affected, they are distinguished:
- Anterior cruciate ligament rupture
- Posterior cruciate ligament rupture
- Rupture of the lateral collateral ligament
- Internal collateral ligament rupture
Depending on the degree of damage to the fibers, there are:
- 1st degree tears - only part of the fibers are damaged, while the overall integrity of the ligament is preserved
- Grade 2 tears – more than half of the fibers are torn, movement in the knee joint is limited
- Grade 3 ruptures – the ligament is completely torn, the joint is unstable, pathological mobility is observed
Causes of knee ligament rupture
Knee ligament ruptures most often occur when performing physical exercises that place stress on the joint, or when direct force is applied, such as a direct blow to the knee.
The rupture of specific ligaments depends on certain types of movements:
- A rupture of the anterior cruciate ligament is associated with the application of a force that is directed forward into the area of the posterior surface of the knee joint, while the lower leg is bent and rotated inward.
- Rupture of the posterior cruciate ligament - most often occurs when the leg is sharply extended at the knee joint or when the blow falls on the front surface of the shin, while the leg is bent at the knee joint.
- Rupture of the external collateral ligament - occurs when the lower leg deviates inward when walking on uneven terrain, awkward movements, or twisting the leg when walking in high heels.
- A torn medial collateral ligament occurs when the lower leg deviates outward.
Often, combined damage to the ligaments of the knee joint occurs when damage occurs, for example, to the lateral and cruciate ligaments at the same time. In such cases, hemorrhage into the joint may occur (hemarthrosis is formed) and the period of rehabilitation of joint functions is significantly extended.
Symptoms of a torn knee ligament
Symptoms that may indicate damage to the ligamentous apparatus of the knee include the following:
- Sharp pain in the knee
- Swelling of the knee area (the knee joint increases in size)
- Weak cracking sounds during injury, resulting from rupture of ligament fibers
- At the time of injury or fall, you may feel a sensation of “dislocation” of the lower leg to the side or anteriorly
- Limitation of range of motion in the joint or, on the contrary, “looseness”, instability of the knee joint (symptoms of the anterior and posterior “drawer”)
- Inability to put weight on the affected leg when walking
- Pathological mobility of the patella when pressing with the fingers while the leg is straightened at the knee joint (patellar balling)
Diagnosis of knee ligament rupture.
If there are symptoms of patellar ligament rupture, the examination will be carried out by a traumatologist. The examination begins with an external examination and palpation of the knee joints, then additional instrumental examination methods may be required, such as:
- X-ray examination of the knee joint
- Magnetic resonance imaging
- Ultrasound examination of the knee joint
These tests will help diagnose soft tissue injuries and bone fractures that may have been caused by the injury.
After assessing the patient’s condition, the doctor draws up a treatment plan, which includes:
- Rest – During the first time after an injury, it is necessary to limit movement to a minimum to reduce pain and swelling, prevent further damage and create the preconditions for an earlier recovery.
- Cold - applying cold compresses, ice packs and other cryotherapy methods in the first 24 hours after a rupture causes the blood vessels to constrict, which leads to a decrease in swelling and hemorrhage in the tissue.
- Elastic bandages, bandages, bandages - create pressure on the knee area, prevent the formation of swelling, stabilize the knee joint, and limit pathological movements.
- Giving the leg an elevated position - with the help of improvised objects (for example, a pillow) or special medical equipment, the leg is raised above the level of the heart. At the same time, the flow of large amounts of blood to the site of injury is hampered, and tissue swelling is reduced.
- The fight against pain is carried out with the help of non-steroidal anti-inflammatory drugs (ketorolac, diclofnac, ibuprofen), which the doctor prescribes both in the form of tablets for oral administration and in the form of pain-relieving creams, ointments, lotions.
- Heat - you can start using warming compresses, ointments, and heating pads on the knee area only a few days after the ligament ruptures, after bleeding from small vessels has stopped. Such procedures provide pain relief for the patient.
- Physiotherapy - paraffin applications, UHF, diadynamic currents, electrophoresis are used. A set of physical exercises must be performed regularly during the rehabilitation period to restore muscle strength and mobility in the joint.
- Massage – performed either by a specialist or in the form of self-massage to relieve pain and swelling.
- Surgical treatment – used for complete rupture of one or more ligaments, joint instability and ineffectiveness of conservative treatment methods.
When treating knee ligament ruptures, preference is given to minimally invasive operations, in which surgery to restore the integrity of the ligament is performed only through two small incisions. This procedure uses special endoscopic instruments to see what is happening inside the joint cavity on a monitor screen. It is also possible to use autografts (tendons are taken from the patient himself from accessible areas) or prostheses made of synthetic tissue to restore ligaments. Be healthy!
Treatment of posterior cruciate ligament rupture.
Patient management tactics are individually selected by a specialist depending on the general picture of the disease, lifestyle and age characteristics:
Conservative technique
It is suitable when the position of the lower leg remains stable after injury. At first, you need to apply cold to the damaged area and take medications to reduce pain and swelling. During the treatment period, it is necessary to limit the movement of the knee by using orthoses and braces. The doctor eliminates hemarthrosis by puncturing the joint with a syringe. Intra-articular injections of platelet-rich plasma and hyaluronic acid help speed up the healing process and reduce inflammation. Gradually, when the swelling decreases, therapeutic exercises are prescribed to strengthen the muscles. Physiotherapeutic procedures help speed up the healing process.
Surgery
Arthroscopy is used as the most gentle method that promotes a speedy recovery, as well as the most effective. The reason for surgery is instability in its work, pathological movements, which additionally cause microtrauma to the articular cartilage and meniscus, which provokes the development of arthrosis. If there are indications, the patient is prepared for surgical treatment. The operation then provides access to the joint by making small incisions in the skin - just enough to insert the arthroscope and surgical instruments into the cavity. Due to the fact that the image of the joint structures is transmitted from the arthroscope camera to the monitor, visualization of the joint structures is provided at multiple magnification. The specialist determines the area of damage, then decides what manipulations need to be performed and immediately performs them.
If the PCL is ruptured, its repair is performed arthroscopically using an autograft. Typically, the semitendinosus tendon is used. This method of treatment helps to restore lost functions. If deformation of other tissues is detected, their integrity is restored if possible. After arthroscopy, the patient is discharged on the day of surgery. Subsequently, to ensure better results after surgery, it is recommended to visit a doctor and undergo a rehabilitation course.
You can read more about knee arthroscopy on our website:
Rehabilitation after PCL injury
Rehabilitation activities include a whole course of exercises, procedures and the use of auxiliary devices, which are developed individually for each person. First of all, fixation of the joint is necessary. Then a gradual increase in loads is carried out by prescribing physical therapy and mechanotherapy. Physiotherapy is needed to speed up healing. Sometimes, for the same purposes, a course of intra-articular injections of PRP or hyarulonates is carried out. Initially, the patient performs the exercises in the clinic, then they are allowed to perform them at home. The minimum rehabilitation period is 3 months.
Forecast
Most often, the prognosis for this type of injury is favorable. Even with conservative treatment, a return to sports activities is possible, since knee stabilization is achieved by training the anterior thigh muscles. After plastic surgery of the ligament and completion of a course of postoperative rehabilitation, as a rule, the function of the joint, its stability, is completely restored, and it becomes possible to return to sports activities.
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Rehabilitation
The principles of rehabilitation during conservative treatment are similar to postoperative ones.
As a rule, in order to allow the ligament to recover in a neutral position, several important rules must be followed:
- Limit your exposure to gravity. Advise the patient to avoid positions that cause tibial sag, such as wall squats, for 6 weeks. You may also encourage the patient to place a pillow under the proximal tibia while sleeping.
- One of the most important components of the treatment of PCL injury is wearing a dynamic orthosis (brace). It acts as a spring to prevent excessive posterior translation of the tibia. Thus, the brace does not allow the bone to “sag”. Ideally, you should wear the brace 24/7 for 16 weeks, only removing it when showering. In 2010, a study was conducted in which 21 people took part. All subjects wore the orthosis for a whole year. According to the data obtained, the use of the orthosis helped reduce posterior advancement of the tibia by 2.3 mm. The data obtained indicate that the brace actually has healing properties and can be used to reduce the degree of damage. If the patient does not have the financial ability to purchase a dynamic orthosis, then a removable knee brace can be recommended as an alternative during the acute phase. After this, the patient should wear a hinged bandage with a special pad on the PCL area for 12 months. The wearing period can be increased depending on the stability of the knee joint.
- When working on increasing the range of motion, select exercises with the starting position lying on your stomach. This way you can limit the influence of gravity.
- If the injury is accompanied by intra-articular effusion or bleeding, limit weight-bearing exercise
- Isolated contractions of the hamstrings with the knee bent greater than 15 degrees increase pressure on the PCL. For this reason, avoid such exercises for at least 16 weeks. Instead, you can recommend exercises such as the Romanian deadlift, where the angle of knee flexion is much less, which means there is no excessive stress on the tibia.
Rehabilitation in the acute phase
Goals:
- Restore range of motion.
- Reduce swelling.
- Reduce the inflammatory process.
- Restore muscle function.
Restoring range of motion (weeks 0-4):
- Exercises from a prone position on your stomach are performed with the help of an assistant.
- Next, move on to working on an exercise bike. The angle of flexion at the knee is 115 degrees or as much as is necessary for a full rotation of the pedals on the exercise bike.
Reducing swelling:
- Applying ice.
- Elevated position.
- Limiting the load on the knee.
Muscle Recovery: Learning to activate the quadriceps muscle is important because this muscle pulls the tibia forward, improving knee stability. You can direct the patella upward by forcing the quadriceps to contract in isolation.
Proceed to exercises with weights if the following conditions are met:
- The flexion angle at the knee joint is 130 degrees.
- The knee is fully extended.
- The patient feels comfortable walking with the orthosis.
Late rehabilitation
- Muscle Endurance (Weeks 5-10): Light weight and high reps (eg, 3-4 sets of 15 reps with a 40-second rest). Examples of exercises: Walking forward and backward using a Theraband.
- Bilateral squats.
- Eccentric exercises (for example, descending from a platform or pedestal).
- Romanian deadlift or single leg deadlift.
Return to sports
Before returning to sports, the patient must complete a complete rehabilitation program and strengthen his muscles. The patient's readiness to resume sports training can be assessed using the following criteria:
- Quadriceps strength.
- Balance test (Y balance anterior reach distance).
- Hop test.
What technique do we recommend to perform this surgical intervention?
The most advanced technique for restoring the PCL today is plastic surgery of the ligamentous apparatus using the “all inside” principle (allinside). The advantages of this technique:
- there is no need to drill through bone canals, therefore, less pain after surgery, faster recovery, reduced risk of complications, development of thrombosis, arthrofibrosis and limb dysfunction;
- only one tendon is required, and not two, as with the classical method;
- the thickness of the graft is twice that of the classical technique with screw fixation;
- the absence of implants inside the channels (screws) improves the process of osseointegration in all 3D planes;
- the force to rupture the fixing buttons exceeds the force to rupture the native ligament;
- the structure can be strengthened by augmentation (additional placement) of the internal brace inside the ligament to prevent re-injury and graft rupture, as well as earlier rehabilitation.
This surgical intervention is a gentle and at the same time effective method of treatment. All manipulations are carried out through micropunctures using high-tech equipment, the patient is under anesthesia.
Surgery for cruciate ligament injury
Arthroscopy, in addition to being a diagnostic examination, is used as a method of performing surgery on the knee joint. A microscopic camera is inserted into the joint capsule, and thanks to it, a medical specialist determines the extent of the tear and performs its repair. This is the most gentle and popular method of surgical intervention for treating joints.
For athletes with a partial rupture, surgical treatment is used to prevent the end of the athlete’s sports career.
After the plastic surgery, wearing a special orthosis to fix the knee is required for a certain number of weeks, and walking is not prohibited for the patient from the first day. To restore all functions of the knee joint, physical therapy classes are required: exercises on an exercise bike in the third week, a month later - active swimming in the pool, after 3-4 months smooth running at a high pace is practiced. If all instructions are followed, after six months the patient can return to their normal pace of life.
A complete rupture of the ligaments cannot be treated, and it is impossible to restore the integrity of the ligament. Therefore, when an injury of this severity occurs, doctors perform an operation to replace the cruciate ligament with an autograft (own tendon from another place) or with a prosthesis made from synthetic materials. As a result, the patient will be able to return to physical activity (but with a number of restrictions). In addition, the risk of various types of complications will be reduced: meniscal tears, arthrosis, deformation, and the like.
Osteopathic treatment is often sought after surgery to quickly restore knee function. Although with the help of osteopathic techniques it is often possible to avoid surgery altogether. The gentle but effective actions of an osteopathic doctor can restore injured ligaments using special techniques.
Success of surgical treatment
It consists of the following components:
- academic examination by a qualified surgeon, based on many years of experience working with athletes in a team with rehabilitation specialists, sports medicine doctors, physiotherapists, with the construction of the entire treatment plan until the patient’s complete recovery;
- careful preoperative planning using the latest equipment. The center is equipped with a complex of navigation robotic equipment for precise intraoperative execution of assigned tasks;
- detailed preoperative examination to provide clear indications for a specific surgical intervention;
- minimally invasive surgery. The smaller the incision, the faster the rehabilitation occurs. This rule always works! The operating rooms are equipped with all the necessary equipment, including robotic navigation systems, video complexes for arthroscopy with the ability to receive high-quality streaming video in 4K format, which makes the surgeon’s work much easier;
- coordinated work of the anesthesiological and surgical teams;
- rehabilitation complex from the first hours after surgery/injury.
Basic treatment methods
For minor ruptures, treatment is conservative. Patients are advised to wear an orthosis, take non-steroidal anti-inflammatory drugs (Nise, Nurofen, Ketoprofen) if pain occurs, 5-10 sessions of physiotherapeutic procedures (UHF therapy, electrical stimulation, electrophoresis, magnetic therapy).
In case of serious injury, minimally invasive surgery is performed. After applying a pneumatic tourniquet to the thigh to prevent bleeding, the surgeon makes two small incisions of 0.5 cm each. After introducing an arthroscope and medical instruments (shaver, scissors, nippers), the connective tissue structures are examined and the dimensions of the surgical field are determined. The device is equipped with a miniature video camera, so all joint elements are clearly visualized on the monitor screen. The surgeon removes the detached elements of the PCL, clearing the area for graft placement. Another mini-incision is made through which a small tendon of the femoral muscle is harvested. If this manipulation is impossible, the graft is taken from the patellar ligament. The removed tendon is sutured, then channels are formed in the tibia and femur to remove the graft and fix it in tension position.
For 4-5 weeks after surgery, patients are advised to use crutches when moving. Regular lymphatic drainage of the operated area is carried out, and analgesics are used to eliminate pain. The load on the knee is gradually increased to stimulate blood circulation and prevent post-traumatic osteoarthritis. During the entire rehabilitation period (2-3 months), the patient performs special exercises daily to help increase the functional activity of the joint.
In the absence of medical intervention, 5 years are enough for the complete destruction of hyaline cartilage after a ligament rupture. When the lower leg slips, the patellofemoral joint experiences excessive loads, causing rapid wear of the cartilage tissue of the patella. Therefore, even with a minor injury, you should seek medical help.