Posterior Cruciate Ligament Tear
While an injury of the anterior cruciate ligament is one of the most common sports injuries, a rupture of posterior cruciate ligament (PCL) is rare. However, an injury to the posterior cruciate ligament is equally serious. This type of injury requires an optimal treatment at the earliest stage by a knee specialist in order to avoid lasting damages.
What are the functions of the posterior cruciate ligament?
In combination with the anterior cruciate ligament the posterior cruciate ligament is one of the main stabilizers of the knee and prevents mainly that the lower leg is shifted backward against the thigh. The cruciate ligaments intersect inside of the knee joint and together they form the central stabilization pillar of the knee joint. Only in this combination they ensure the natural movement of the knee joint (see Anatomy Knee Joint)
What are the consequences of a posterior cruciate ligament tear?
A tear of the posterior cruciate ligament causes the knee to become unstable. The fact that the lower leg increasingly pushes backwards against the thigh can cause the knee to buckle, lock, or even to collapse. Consequences may be a cruciate ligament injury, the loss of natural joint movements a meniscus tear or cartilage damage. As a result of this condition, a severe degeneration of the knee, osteoarthritis is developed over the course of years.
How is a posterior cruciate ligament tear diagnosed?
An orthopedist specializing in knee injuries can accurately assess the degree of mobility of the lower leg (tibia) relative to the upper leg (femur) by using special examinations such as the Lachman-Test or Posterior Drawer Test. Here the exact degree of knee instability can be determined by a special measuring method (Rollimeter). Standardized X-rays can reliably show the extent of the instability. A suspected posterior cruciate ligament can additionally be confirmed by magnetic resonance imaging (MRI). An MRI should be performed as a routine, to rule out other associated injuries such as meniscus tear or cartilage damage.
Treatment options – posterior cruciate ligament rupture
If a posterior cruciate ligament injury is diagnosed, it is important to decide for the most optimal treatment. The following criteria will be decisive in determining the treatment:
- degree of instability
- the patient's age and activity level
- associated injuries
Conservative treatment - posterior cruciate ligament rupture
In contrast to an anterior cruciate ligament tear, a posterior ligament tear can often be treated conservative, e.g. without surgery. If the instability is not strongly marked, stability can be satisfactorily achieved through a consequent treatment of the shinbone. Following the treatment, the knee joint muscles should be improved by appropriate strength and coordination training to additionally stabilize the knee muscular.
An orthopedist specializing in knee injuries can accurately assess the degree of mobility of the lower leg (tibia) relative to the upper leg (femur) by using special examinations such as the Lachman-Test or Posterior Drawer Test. Here the exact degree of knee instability can be determined by a special measuring method (Rollimeter). Standardized X-rays can reliably show the extent of the instability. A suspected posterior cruciate ligament can additionally be confirmed by magnetic resonance imaging (MRI). An MRI should be performed as a routine, to rule out other associated injuries such as.
Surgical treatment - posterior cruciate ligament rupture
All patients with severe knee instability and higher levels of physical/sports activities should be urged to undergo surgery replacing the posterior cruciate ligament, since otherwise there is a great risk of osteoarthritis.
The younger the patient the more important is it to opt for a cruciate ligament surgery. Surgery is particularly important if other serious leg injuries are present, such as a torn meniscus or cartilage damage.
What are the procedures in a cruciate ligament tear surgery?
In a cruciate ligament surgery, the non-functional anterior cruciate ligament is replaced with an artificial tissue (graft). New developments in medicine allow the tendon to be replaced with an autologous tendon.
The surgery should be minimally invasive, i.e. performed by arthroscopy. This requires two or three incisions that are only a few millimeters in size for placing a mini camera and small surgical instruments. As an implant, the surgeon uses either two tendons from the inside of the thigh (semitendinosus and gracilis tendon) or a part of the knee extensor tendon (patellar tendon or quadriceps).
The respective tendon graft is extracted via a small, 3 cm long incision. After appropriate preparation, the tendon graft is then threaded through tunnels drilled into the lower leg and the thigh bone respectively. It precisely fits the knee joint and is then fixated. It is secured with screw-type implants, so-called interference screws, which consist of a bioabsorbable material or plastic. Alternatively, the fixation can be done with small titanium plates (endobutton) or a cross pin. In the context of the healing process, the graft grows in the bone and takes over the function of the cruciate ligament.
What type of anesthesia is needed for a knee joint cruciate ligament surgery?
Most of the cruciate ligament surgeries that last approx. 1 to 1.5 hours, are performed with general anesthesia. Due to the medical, technical and pharmacological progress made in recent years, general anesthesia is well tolerated.
General anesthesia is often combined with local anesthetics of the nerves that supply the knee joint. That means that even less medication is needed for general anesthesia and that it is even better tolerated. However, such a decision should only be made on a case to case basis after an appropriate examination of the patient individually decided by the anesthetist. The post-operative pain is due to improved anesthetic procedures and appropriate pain medication usually is not very strong.
What complications are possibly after an anterior cruciate ligament surgery?
Common surgical risks are wound healing, infection of the joint or a thrombosis in the leg.
Even if all possible safety measures are met, these risks can generally not be excluded completely, however, ultimately the risk is very slight. Specific complications associated with the surgery are a residual instability of the knee or a restriction of movement, meaning a lack of full extension or flexion of the knee joint. The risks are reduced if a cruciate ligament specialist performs the operation.
What about post operative care after a cruciate ligament surgery?
By using modern, minimally invasive surgical techniques, the impairment and rehabilitation after cruciate ligament surgery is quite short.
Generally, the surgery requires a hospital stay of one to three nights.
An optimal healing process requires the active participation of the patient, and simultaneously a professional physiotherapy (physical therapy, lymphatic drainage, exercise therapy).
Following the general guide line for the post surgical treatment is strongly recommend, however, the plan may vary depending on the decision of the surgeon and patient:
- Relieving the weight on the operated leg using crutches (about 20 kg weight bearing) for about 2-3 weeks.
- Immediately after surgery, starting tension exercises for muscle toning and gentle physiotherapy as lymphatic drainage and physiotherapy.
- Anti-embolism compression stockings and blood thinning drugs to 10 days after the operation.
- Cooling wraps and possibly taking an anti-inflammatory drug (e.g. diclofenac, ibuprofen) to reduce swelling and relieve pain.
- Protection of the operated knee joint in a special mobility brace for about 6 weeks.
- After 6 weeks starting intensive exercise therapy to improve strength, coordination, and endurance.
- Nach ca. 6-8 Wochen erstes Training auf Radergometer, nach ca. 8-10 Wochen Walking, nach ca. 12-14 Wochen ist leichtes Joggen möglich.
- After the first 6-8 weeks patients may start cycle ergometer training, after about 8-10 weeks walking, and light jogging after about 12-14 weeks.
- Sports with stop-and-go movements (ball sports such as football, basketball, tennis, etc.) with an increased risk of injuries (skiing, snowboarding, inline skating, etc.) should be avoided for about 6-8 months after the surgery since the transplant has healed completely only after that time.
- The time of sick leave after such a surgery is highly dependent on the nature of the job and should be discussed with the treating physician individually.
Specialists: Cruciate Ligament Tear
For an optimal treatment of a cruciate ligament tear/rupture, the knee experts at the Klinik am Ring are particularly well-qualified. Stefan Preis, M.D. and Jörg Schroeder, M.D., senior physicians at the Practice and Department of Orthopedics and Sports Traumatology at the Klinik am Ring in Cologne, specialize together with their team in the treatment of knee and shoulder disorders. In 2004, they founded the WEST GERMAN SHOULDER KNEE & CENTER, Cologne. The team consisting of eight specialists treats more than 10,000 patients per year. Annually they perform more than 1200 knee surgeries, of which are about 120 cruciate ligament surgeries.