Posterior Cruciate Ligament (PCL) Injury.
What is a PCL injury?
The posterior cruciate ligament (PCL) is one of the four major ligaments of the knee, running from the back of the tibia (shin bone) diagonally upward to the front of the femur (thigh bone). It is the strongest ligament in the knee and its primary role is to prevent the tibia from sliding backward on the femur — the opposite of what the ACL prevents. The PCL also contributes to rotational stability and plays a role in proprioception — the knee's sense of position.
PCL injuries are less common than ACL injuries and are frequently missed or underdiagnosed, in part because they tend to produce less dramatic acute presentations and in part because the PCL has a better intrinsic healing capacity than the ACL. They are graded the same way as other ligament injuries — grade 1 (minor stretch), grade 2 (partial tear), grade 3 (complete rupture) — and management depends significantly on the grade and the presence of associated injuries.
What causes PCL injuries?
PCL injuries can occur in various circumstances including sports injuries, car accidents, or falls. The most common mechanism is a direct blow to the front of the shin with the knee bent — the classic "dashboard injury" in motor vehicle accidents, or a fall onto a bent knee in contact sport. The force drives the tibia backward, stressing or rupturing the PCL. It is also commonly injured as part of complex knee trauma involving multiple ligaments.
Unlike ACL injuries, isolated PCL tears from non-contact mechanisms (pivoting, landing) are rare. When the PCL is injured without a direct blow, other structures — the LCL, posterolateral corner, or MCL — are frequently involved and must be assessed carefully.
What are the symptoms?
Acutely, PCL injuries produce posterior knee pain, swelling and a sense of instability, though the presentation is often less dramatic than an ACL rupture. The posterior drawer sign — in which the tibia sags backward compared to the uninjured knee when the knee is held at 90 degrees of flexion — is the most characteristic clinical finding.
Chronically, the hallmark of PCL deficiency is a posterior tibial sag that alters knee mechanics and progressively increases load on the medial compartment and patellofemoral joint, contributing to early degenerative change if left unaddressed. Patients often describe vague knee pain, difficulty with stairs and squatting, and a sense of the knee feeling unreliable under load.
How is it diagnosed?
Clinical assessment involves specific PCL tests — the posterior drawer test, posterior sag sign, and quadriceps active test — alongside comprehensive assessment of the surrounding ligamentous structures. MRI is the gold standard for confirming the diagnosis, grading the tear, and identifying associated injuries including posterolateral corner involvement, meniscal tears, and bone bruising.
How can physiotherapy help?
Most non-severe grade I and II PCL tears are primarily treated by physiotherapy and don't require surgery. Even grade III complete tears are frequently managed conservatively in active patients, with surgery reserved for cases where instability persists after adequate rehabilitation, or where associated injuries — particularly posterolateral corner damage — require surgical reconstruction.
The key to successful conservative PCL management is a structured and progressive program that centres on one distinctive principle: the quadriceps is the dynamic substitute for the PCL. The quadriceps pulls the tibia forward, directly counteracting the posterior tibial sag that PCL deficiency creates. Building quadriceps strength — particularly the VMO — is therefore the foundation of PCL rehabilitation in a way that differs from other knee ligament injuries.
In the acute phase, protected weight-bearing, swelling management and early quadriceps activation are the priorities. A posterior splint or brace may be used to prevent the tibia from sagging backward during the healing phase. Physiotherapy begins gentle quadriceps activation and range-of-motion work within comfortable limits.
As the acute phase settles, progressive quadriceps strengthening is the core of rehabilitation — initially with open-chain exercises (straight leg raises, terminal knee extensions) before progressing to closed-chain loading. Hamstring strengthening requires careful management in PCL rehabilitation — isolated hamstring curls that pull the tibia backward are typically avoided or modified in the early phases to avoid stressing the healing PCL.
Hip abductor, gluteal and calf strengthening, balance and proprioception training, and gait retraining complete the rehabilitation program before return to sport. Return to cutting, pivoting and contact sport is guided by objective quadriceps strength testing and functional hop testing rather than symptoms alone.
For patients requiring surgical reconstruction — typically those with grade III tears and persistent instability, or combined ligament injuries — physiotherapy is equally important before and after surgery, and our dedicated PCL reconstruction rehabilitation page covers the post-surgical pathway.
Clinical Pilates provides an excellent environment for progressive quadriceps and hip strengthening with precise load modification. Real time ultrasound assists in retraining VMO activation where inhibition is affecting rehabilitation progress. For patients whose PCL injury occurred in a motor vehicle accident, CTP funded rehabilitation is available. WorkCover funded rehabilitation is also available for workplace injuries.
Our physiotherapists Eliane Machado, Bethany Kippen and Emma Cameron all have experience in knee ligament injury management and are members of the Australian Physiotherapy Association.
To book or find out more, call us on 07 3706 3407 or book online below. We see patients from across Brisbane's southside including Tarragindi, Coorparoo, Holland Park, Greenslopes and Mt Gravatt.
The posterior cruciate ligament (PCL) is one of the four major ligaments of the knee, running from the back of the tibia (shin bone) diagonally upward to the front of the femur (thigh bone). It is the strongest ligament in the knee and its primary role is to prevent the tibia from sliding backward on the femur — the opposite of what the ACL prevents. The PCL also contributes to rotational stability and plays a role in proprioception — the knee's sense of position.
PCL injuries are less common than ACL injuries and are frequently missed or underdiagnosed, in part because they tend to produce less dramatic acute presentations and in part because the PCL has a better intrinsic healing capacity than the ACL. They are graded the same way as other ligament injuries — grade 1 (minor stretch), grade 2 (partial tear), grade 3 (complete rupture) — and management depends significantly on the grade and the presence of associated injuries.
What causes PCL injuries?
PCL injuries can occur in various circumstances including sports injuries, car accidents, or falls. The most common mechanism is a direct blow to the front of the shin with the knee bent — the classic "dashboard injury" in motor vehicle accidents, or a fall onto a bent knee in contact sport. The force drives the tibia backward, stressing or rupturing the PCL. It is also commonly injured as part of complex knee trauma involving multiple ligaments.
Unlike ACL injuries, isolated PCL tears from non-contact mechanisms (pivoting, landing) are rare. When the PCL is injured without a direct blow, other structures — the LCL, posterolateral corner, or MCL — are frequently involved and must be assessed carefully.
What are the symptoms?
Acutely, PCL injuries produce posterior knee pain, swelling and a sense of instability, though the presentation is often less dramatic than an ACL rupture. The posterior drawer sign — in which the tibia sags backward compared to the uninjured knee when the knee is held at 90 degrees of flexion — is the most characteristic clinical finding.
Chronically, the hallmark of PCL deficiency is a posterior tibial sag that alters knee mechanics and progressively increases load on the medial compartment and patellofemoral joint, contributing to early degenerative change if left unaddressed. Patients often describe vague knee pain, difficulty with stairs and squatting, and a sense of the knee feeling unreliable under load.
How is it diagnosed?
Clinical assessment involves specific PCL tests — the posterior drawer test, posterior sag sign, and quadriceps active test — alongside comprehensive assessment of the surrounding ligamentous structures. MRI is the gold standard for confirming the diagnosis, grading the tear, and identifying associated injuries including posterolateral corner involvement, meniscal tears, and bone bruising.
How can physiotherapy help?
Most non-severe grade I and II PCL tears are primarily treated by physiotherapy and don't require surgery. Even grade III complete tears are frequently managed conservatively in active patients, with surgery reserved for cases where instability persists after adequate rehabilitation, or where associated injuries — particularly posterolateral corner damage — require surgical reconstruction.
The key to successful conservative PCL management is a structured and progressive program that centres on one distinctive principle: the quadriceps is the dynamic substitute for the PCL. The quadriceps pulls the tibia forward, directly counteracting the posterior tibial sag that PCL deficiency creates. Building quadriceps strength — particularly the VMO — is therefore the foundation of PCL rehabilitation in a way that differs from other knee ligament injuries.
In the acute phase, protected weight-bearing, swelling management and early quadriceps activation are the priorities. A posterior splint or brace may be used to prevent the tibia from sagging backward during the healing phase. Physiotherapy begins gentle quadriceps activation and range-of-motion work within comfortable limits.
As the acute phase settles, progressive quadriceps strengthening is the core of rehabilitation — initially with open-chain exercises (straight leg raises, terminal knee extensions) before progressing to closed-chain loading. Hamstring strengthening requires careful management in PCL rehabilitation — isolated hamstring curls that pull the tibia backward are typically avoided or modified in the early phases to avoid stressing the healing PCL.
Hip abductor, gluteal and calf strengthening, balance and proprioception training, and gait retraining complete the rehabilitation program before return to sport. Return to cutting, pivoting and contact sport is guided by objective quadriceps strength testing and functional hop testing rather than symptoms alone.
For patients requiring surgical reconstruction — typically those with grade III tears and persistent instability, or combined ligament injuries — physiotherapy is equally important before and after surgery, and our dedicated PCL reconstruction rehabilitation page covers the post-surgical pathway.
Clinical Pilates provides an excellent environment for progressive quadriceps and hip strengthening with precise load modification. Real time ultrasound assists in retraining VMO activation where inhibition is affecting rehabilitation progress. For patients whose PCL injury occurred in a motor vehicle accident, CTP funded rehabilitation is available. WorkCover funded rehabilitation is also available for workplace injuries.
Our physiotherapists Eliane Machado, Bethany Kippen and Emma Cameron all have experience in knee ligament injury management and are members of the Australian Physiotherapy Association.
To book or find out more, call us on 07 3706 3407 or book online below. We see patients from across Brisbane's southside including Tarragindi, Coorparoo, Holland Park, Greenslopes and Mt Gravatt.
