Posterior Cruciate Ligament Injury

By admin On Feb 23, 2024

Ovid: 5-Minute Orthopaedic Consult

Editors: Frassica, Frank J.; Sponseller, Paul D.; Wilckens, John H.

Title: 5-Minute Orthopaedic Consult, 2nd Edition

> Table of Contents > Posterior Cruciate Ligament Injury

Posterior Cruciate Ligament Injury

Marc Urquhart MD

John H. Wilckens MD

Basics

Description

Injury to the OSD, the primary stabilizer to posterior translation of the tibia on the femur at the knee (1)
Classification (see “Posterior drawer test” under “Physical Exam”) (2):
- Grade 1: Tibial plateau is anterior to the femoral condyles.
- Grade 2: Tibial plateau is level with the femoral condyles.
- Grade 3: Tibial plateau is posterior to the femoral condyles.

Epidemiology

Young adults
Males affected more than females

Incidence

Uncommon

Risk Factors

Motor vehicle accident
Participation in collision sports
Hyperextension injury to the knee

Genetics

No Mendelian pattern is known.

Etiology

Direct blow to the anterior tibia with the knee flexed and the foot plantarflexed
Hyperflexion without a blow
Hyperextension

Associated Conditions

Popliteal artery injury

Diagnosis

Signs and Symptoms

Knee pain and swelling after the injury with gradual improvement in generalized pain symptoms
Minimal symptomatic instability, usually when climbing stairs
Recurrent effusion
Posterior knee pain
Knee recurvatum (late finding)

Physical Exam

Perform a complete neurovascular examination.
Tests for ligamentous stability:
- Posterior drawer test:
  - Position the patient supine with the knee flexed 90° and the foot stabilized on the examination table.
  - Apply posterior force to the anterior tibia.
  - Note the excursion of the tibia underneath the femoral condyles.
  - Note the quality of the end point.
  - Compare the involved and contralateral sides.
  - The position of the affected knee can
    reveal a posterior sag of the tibia when the patient is supine with
    hips flexed 45°, knees flexed 90°, and feet flat on the examination
    table.
- Lachman test:
  - Anterior drawer test at 30° of flexion
  - To rule out associated ACL rupture
- Rule out collateral ligament injury

Tests

Lab

None indicated

Imaging

Radiography:
- Plain film AP and lateral views of the knee:
  - To evaluate for fracture about the knee
  - May reveal an avulsion fracture off the proximal posterior tibia
- Stress radiography
MRI is very sensitive for identifying PCL injury and associated injuries

Pathological Findings

Either midsubstance rupture or proximal or distal bony avulsion is noted.

Differential Diagnosis

ACL injury
Tibial plateau fracture
Meniscal tear

Treatment

General Measures

Patients may be partial weightbearing as tolerated.
History and physical examination for a provisional diagnosis
Radiography and MRI to confirm the diagnosis
Nonoperative treatment initially, except for high-grade injuries/knee dislocations
Knee immobilizer and crutch ambulation as tolerated until comfortable
Early ROM and strengthening
Knee braces are of questionable use.

P.339

Special Therapy

Physical Therapy

A specific OSD-insufficiency knee program is initiated.

Medication

First Line

NSAIDs
Acetaminophen

Second Line

Mild, as-needed narcotics for acute/severe pain

Surgery

Relative indications for surgery:
- Grade 3 PCL injuries
- Posterolateral corner injuries
- Associated ligamentous, meniscal, or articular surface injuries
- Giving-way of the knee
- Pain
- Radiographically documented progressive articular deterioration
Reduction and internal fixation of avulsion fractures
Reconstruction is reserved for patients with symptomatic swelling and activity-related pain (3).
- The procedure entails reconstruction of the ligament with an autograft or allograft.
- Arthroscopically assisted reconstructions are demanding technically but obviate wide surgical exposure.

Follow-up

Prognosis

Extremely good
Most patients do not require surgery (4).

Complications

Recurrent symptomatic giving-way of the knee
Failure of reconstruction
Progressive medial compartment arthrosis, followed by patellofemoral compartment arthrosis

Patient Monitoring

Patients are followed at 3–6-month intervals to check on their prognosis with ROM, muscle strength, and function.

References

1. Miller MD, Bergfeld JA, Fowler PJ, et al. The posterior cruciate ligament injured knee: principles of evaluation and treatment. Instr Course Lect 1999;48:199–207.

2. Shelbourne
KD, Rubinstein RA, Jr. Methodist Sports Medicine Center’s experience
with acute and chronic isolated posterior cruciate ligament injuries. Clin Sports Med 1994;13:531–543.

3. Johnson
TS, Cosgarea AJ. Posterior cruciate ligament injuries. In: Garrick JG,
ed. Orthopaedic Knowledge Update: Sports Medicine 3. Rosemont, IL:
American Academy of Orthopaedic Surgeons, 2004:155–168.

4. Shelbourne
KD, Davis TJ, Patel DV. The natural history of acute, isolated,
nonoperatively treated posterior cruciate ligament injuries. A
prospective study. Am J Sports Med 1999;27:276–283.

Miscellaneous

Codes

ICD9-CM

717.84 Disruption of the posterior cruciate ligament

Patient Teaching

Isolated PCL injuries often are treated nonoperatively.

FAQ

Q: What is the natural history of nonoperatively treated isolated PCL injuries?

A:
Most patients are able to return to functional activity in 6–8 weeks.
Although progressive laxity is uncommon, patients can develop medial
and patellofemoral compartment changes over the ensuing years of PCL
laxity.

Q: Are other injuries associated with PCL injury?

A:
Low-energy PCL injuries usually are isolated. However, high-energy PCL
injuries usually are accompanied by collateral ligament injury and/or
ACL injury. A patient with a high-energy PCL tear should be evaluated
for concomitant vascular and neurologic injury.