Posterior Cruciate Ligament (PCL) is the other major stabilizing ligament located centrally in the knee similar to the ACL. Unlike the ACL; PCL is on the backside of the knee, hence called the ‘Posterior’ Cruciate Ligament. It is a posterior stabilizer for the knee. It forms a central pivot along with the ACL placed in a cruciate (cross) arrangement with each other. It is a much larger and stronger ligament as compared to the ACL.
A PCL tear is known to occur in sports injuries and due to a direct fall on the knee. However it is more commonly inured in road traffic accidents where the knee happens to dislocate. In these situations the PCL injury is commonly associated with multiple other ligament injuries around the knee. This multi-ligament injury of knee needs careful assessment for a correct and complete diagnosis for appropriate management.
Unlike an ACL injury, the isolated PCL injury may not always present with obvious symptoms. However one may feel a subtle difference in the affected knee as compared to the normal side. More commonly one would have pain in the knee. If it is associated with multiple other ligament involvement as in a knee dislocation symptoms of instability become more obvious.
Immediately following injury, one may have a classical abrasion/bruise in front of the knee at the site of impact. There may be discoloration of skin visible on the back/inner/outer side of knee if there are multiple ligaments involved with the PCL.
If the injury is long standing due to neglect, one may start developing pain in the knee and limitation in terminal knee bending. One would also have difficulty in negotiating stairs.
The surgeon correlates ones history of injury along with a clinical examination. The laxity of knee is tested along with an examination for detecting any other associated injuries.
The clinical diagnosis is then correlated with X-Ray and MRI findings to confirm a precise and complete diagnosis. It is important to not miss out on associated injuries, which may also need a combined management. A PCL injury is more commonly associated with multiple ligament involvement than an ACL injury. A neglect/overlook of associated injuries is known to cause long-term failure of a PCL reconstruction.
It is advisable that one comes for a consult with these basic investigations
• X-ray : Both knees – AP in standing / Lateral
• MRI of the affected knee
Immediately following the injury it is best to follow the P.R.I.C.E.R principle. A ‘rigid long knee brace’ is sufficient for initial immobilization along with ice application.
It is however important to get an appropriate assessment done at this acute stage to confirm on the extent of injury. Missing out on this golden period of early assessment may amount to a neglect of certain associated injuries and then give substandard long-term results if treated late.
All injuries to the PCL may not require surgical management. Only symptomatic knees with clinically significant findings may require a surgical intervention. Injuries requiring surgery can be treated by special arthroscopic techniques (Key hole surgery). Some may require mini-open/open surgical procedures.
PCL preservation :
If the injury is detected early and the PCL is repairable, one can fix the ligament back in its original position and preserve the native PCL. These repairs can be all arthroscopic methods or may require an open surgery. This depends on the type of injury to the PCL. If associated with multiple ligament involvement, it may require additional repairs to give optimal results.
PCL reconstruction :
All PCL injuries may not be repairable, especially if it is a late presentation. These would require PCL reconstruction. In this procedure ones own tissue (hamstring tendon) is harvested and fashioned into a ligament. This is then fixed into the knee with small titanium buttons/screws with a special arthroscopic technique. If multiple ligaments require reconstruction / in revision cases, grafts may be acquired from the contralateral knee OR allografts (cadaveric grafts) may be necessary.
Latest, advanced technique for arthroscopic PCL reconstruction -
The standard old technique for PCL reconstruction involves taking the hamstring graft from front of the knee. This results in the surgical scars being visible on front of the knee. It also has certain risks and complications related to it with regards to the quality of graft and risk of nerve injury.
Dr.Kodkani performs a cosmetic, minimally invasive technique of hamstring graft harvesting. This technique is used for PCL reconstructions as well, which is now followed by many surgeons in India and internationally.
This technique involves harvesting of the graft from a small incision on back of the knee. The surgical scar therefore stays hidden on the back side and front of the knee hardly has any visible scars. This technique also has numerous added technical advantages, which avoid the risks and complications associated with the older methods of PCL reconstruction.
(Comparative pictures of old procedure of PCL reconstruction Vs New procedure of PCL reconstruction)
Rehabilitation following arthroscopic PCL reconstruction -
The surgery requires hospitalization for 3 days. This is for medication, initial physiotherapy, training for mobilization and postoperative care.
• Rigid long knee brace for 4 weeks with posterior calf padding
• Hinged knee cap for 6-9 months
• Walking is permitted from day of surgery. There is no period of compulsory bed rest.
• Use of crutches/walker for upto 1 week following which one may walk without any support.
Knee movements –
• Knee range of motion exercises and physiotherapy start from 2 weeks following surgery.
• One can expect full range of motion by 1½ month following surgery
Toning and strengthening –
• Training for these exercises is given by the physiotherapist during the hospital stay.
• An exercise program is tailored for sports specific training
Return to activities of daily living -
• One is able to resume normal activities of daily living by suture removal (10 days)
Return to sports –
• 6 – 9 months. This depends on individual progress in recovery and the sport one is involved in.
The physiotherapy protocol and recovery would vary depending on any associated procedures performed in addition to an PCL reconstruction