Tibial tuberosity transfer (TTT) is a surgical procedure involving cutting the bony bump below the kneecap (the tibial tuberosity) and either moving it or re-angling it with a view to changing the forces through the patella.
Page updated September 2023 by Dr Sheila Strover (Clinical Editor)
There are several different procedures in this group and they are also called a tibial tubercle transfer or tibial tubercle osteotomy. A tibial tubercle transfer or osteotomy is usually performed to improve symptoms in patellar instability. Because such corrective surgery is performed distal to the patella (below it) the group of procedures are referred to as distal realignment procedures.
Extensor mechanism realignment
The extensor mechanism is the chain of bone-tendon-bone- muscle, reaching from the upper tibia right to the hip, that allows active extension of the knee. The patella at the centre of the chain acts as a fulcrum as it is contained within the groove of the femur. Sometimes the alignment is not ideal and the patient may suffer from subluxations or dislocations of the patella, or long-standing patellar pain. In these cases, the knee surgeon may seek to change the alignment of this so-called extensor mechanism by changing the forces either above or below the patella. These are referred to as proximal realignments and distal realignments. A TTT is a distal realignment.
TTT for patellar instability
TTT is one of a number of distal realignment procedures that seek to address patellar instability. In this case, the doctor will have determined that the attachment of the patellar tendon does not offer optimal alignment of the patella in its underlying groove.
Post-op experiences after Fulkerson osteotomy
- Considering surgery to lengthen patella tendon
A long conversation including many aspects of tibial tubercle osteotomy.
Citation: Grimm NL, Lazarides AL, Amendola A. Tibial Tubercle Osteotomies: a Review of a Treatment for Recurrent Patellar Instability. Curr Rev Musculoskelet Med. 2018 Jun;11(2):266-271. doi: 10.1007/s12178-018-9482-3. PMID: 29721692; PMCID: PMC5970117.
Quotes: "Although excellent outcomes can be achieved, this procedure is not without complications..." "The Maquet technique...has largely been abandoned...for skin necrosis, compartment syndrome, and nonunion." "Nonunion is a recognized risk after tibial tubercle transfer" as well as "fracture of the proximal tibia...increased when the tibial tubercle is completely detached from its hinge."
Relevant material -
- Tibial tuberosity
- Patellar instability
- Distal realignment
2013 - Surgery for patellar malalignment (part of a course on Patellofemoral Pain) - by Dr Ronald Grelsamer (Knee Surgeon)