PCL Avulsion Fixation: Surgical Approaches
For displaced PCL avulsion fractures, both open posterior approach and arthroscopic suture fixation achieve excellent clinical outcomes with stable knees, and the choice depends primarily on fragment size and surgeon expertise. 1
Indications for Surgical Fixation
Displaced PCL avulsion fractures should undergo operative fixation to restore knee stability and prevent secondary joint changes. 2 The literature consistently demonstrates excellent outcomes with low complication rates when these injuries are surgically addressed. 2
- Non-displaced fractures may be managed conservatively, but any displacement warrants surgical intervention 2
- Multi-ligamentous injuries often accompany PCL avulsions and require comprehensive surgical planning 2
Open Posterior Approach
The open posterior (minimally invasive dorsal) approach is the preferred technique for larger bony fragments amenable to screw fixation. 3, 1
Surgical Technique:
- Patient positioned supine with mediodorsal skin incision over the medial gastrocnemius head 3
- Medial gastrocnemius retracted laterally, protecting popliteal neurovascular structures 3
- Posterior capsule incised from tibial attachment, exposing the fracture and PCL 3
- Reduction achieved and provisionally fixed with drill wires 3
- Definitive fixation with two cannulated cancellous screws for adequate-sized fragments 4, 3
Clinical Outcomes:
- Lysholm scores range 85-100 at final follow-up 1
- 92-100% of patients achieve normal or nearly normal IKDC scores 1
- Side-to-side difference of 0-5 mm on stress testing 1
- Average flexion of 121.7°±9.2° with full extension in all patients 4
- Fracture union achieved in all cases with stable early fixation 4, 3
Arthroscopic Suture Fixation
Arthroscopic suture fixation is indicated when the avulsed fragment is small, comminuted, or inadequate for screw fixation. 5, 1
Surgical Technique:
- Three portals utilized: parapatellar anteromedial, high posteromedial, and posterolateral 5
- PCL tibial guide used to create two bone tunnels from anterior tibial cortex to medial and lateral borders of avulsion site 5
- Fixation achieved with 23-gauge wire strands or multiple nonabsorbable sutures through tunnels 5
- Suture anchors may be used for severely comminuted fragments 3
Clinical Outcomes:
- Lysholm scores range 80-100 at final follow-up 1
- 90-100% of patients achieve normal or nearly normal IKDC scores 1
- Side-to-side difference of 0-5 mm on stress testing 1
- Allows rigid fixation and early rehabilitation despite small fragment size 5
Comparative Analysis
Both approaches demonstrate comparable excellent clinical outcomes, radiological healing, and knee stability. 1 A systematic review with mean Coleman methodology score of 72.4 found no clinically significant differences between techniques. 1
Decision Algorithm:
- Large, single bony fragment → Open posterior approach with cannulated screw fixation 4, 3
- Small or comminuted fragment → Arthroscopic suture or wire fixation 5, 3
- Multi-ligamentous injury → Consider open approach for comprehensive repair 2
- Surgeon expertise → Choose technique with which surgeon has greatest experience 1
Postoperative Rehabilitation
- Partial weight bearing of 10-20 kg for 4-6 weeks 3
- Knee flexion limited to 90° for first 4 weeks 3
- Early controlled mobilization following stable fixation produces excellent results 4
- Special PCL rehabilitation protocol for suture anchor fixation or multi-ligamentous repairs 3
Critical Pitfalls to Avoid
- Do not delay surgery for displaced fractures – secondary joint changes develop without anatomic reduction 2
- Do not dismiss late-presenting patients – good to fair results achievable even beyond 12 weeks, though outcomes may be slightly inferior 4
- Do not use screw fixation for small/comminuted fragments – suture or wire fixation provides superior stability in these cases 5
- Do not overlook associated injuries – carefully assess for posterolateral corner injury and multi-ligamentous involvement 3