The Telos stress x-ray after the failure of the patellar tendon graft showing 15 mm of posterior displacement.
PCL Re-tensioning
This 36 year old patient sustained a posterior cruciate ligament injury in1994. He underwent a PCL reconstruction using a patellar tendon graft fixed with interference fit screws. The tibial screw was advanced to the proximal end of the tibial tunnel.
Click on the photos to see a large picture.
The Telos stress x-ray after the failure of the patellar tendon graft
showing 15 mm of posterior displacement.
When the patellar tendon graft failed after another injury, he had an onlay patellar tendon graft harvested from the opposite knee. Dr. Jung Young from Seoul Korea and Dr. John Bergfeld have both popularized this technique.
The technique of the posterior patellar tendon onlay graft. (Drawings
courtesy of Dr. John Berfeld)
Post operatively he developed a severe DVT, with a pulmonary embolism. He was treated with heparin and coumadin for 3 months. At 7 weeks post op, when he was in pool therapy, he slipped and fell, sustaining a hyperflexion injury. When examined after this injury he had a significant posterior displacement. The tibial bone plug had pulled loose, as seen in the Telos stress x-ray seen below. For several reasons, the DVT being the most important, surgery was delayed.
The Telos stress xray after the onlay graft showing 15 mm of posterior
displacement. The plain xray showed that the staples had pulled loose. The ideal fixation
would be screws, but the existing screw made that method of fixation impossible.
There were several choices for revision:
Drill a tibal tunnel with a coring reamer and remove the screw.
Make 2 small 6 mm tunnels for double loop semi-t harvested from both knees. Put the tunnels beside the screw.
Asses the graft arthroscopically, if a graft is still present, re-tension the graft as recommended by Dr. Young from Seoul Korea.
Plan A was to retension the graft.
The procedure.
The arthroscopy revealed a substantial bundle of graft. A posteromedial approach was made, the staples were removed, a bone block was cut from the tibia with the attached graft. The screw was cut out and removed posteriorly. Sutures of No 5 Ticron was placed through and around the bone plug and the bone plug was moved distally. The bone block was also secured with a staple. The sutures were tied over a button on the anterior periosteal surface.
The operative view of the posterior bone block that has been pulled
down into the defect left by removal of the screw.
The diagram of the distal re-tensioning of the tibial bone block.
Conclusions
The technique of re-tensioning the patellar tendon graft is easily performed. The open posteromedial approach has been described by Burks(1). The technique of re-tensioning of the tibial attachment of both the native PCL and the patellar tendon graft has been presented to the Global Arthroscopy Study Group by Dr. Young in 1998. However, this technique should be practiced in the cadaver lab to become confident with the anatomy.
1. Burks RT, Schaffer JJ. A simplified approach to the tibial attachment of the posterior cruciate ligament. Clin Orthop 1990 May;(254):216-9