BLOG: Thoughts on the current state of patella instability surgery
In this entry, I will discuss my thoughts on the state of patella instability surgery. Of note, I will detail the importance of accurate decision-making, the efficacy of medial patellofemoral ligament reconstruction and the indications for medial reconstruction and tibial tubercle transfer.
Accurate decision-making about the origins of instability will lead to good surgical control of instability. In general, one should use the most accurate and least invasive approaches whenever possible.
Medial patellofemoral ligament (MPFL) or medial quadriceps tendon-femoral ligament (MQTFL) reconstruction is highly effective, if properly done, for achieving patella stability. These procedures are preferable, usually, to imbrication, but must be done correctly.
Medial reconstruction should only stabilize the patella and should not be used to displace or move the patella. Medial reconstruction must be achieved with precise anatomic accuracy.
Radiographs and digital imaging provide an approximation of femoral MPFL origin, but final femoral fixation must be based on anatomy. The adductor magnus tendon leads to the adductor tubercle, which is the key to anatomic accuracy. Make the incision large enough to identify it accurately every time. Put the graft just at the distal adductor tubercle.
The results of MQTFL reconstruction are comparable to MPFL reconstruction and eliminate the risk of patella fracture.
The following are my thoughts regarding tibial tubercle transfer, rotational osteotomy and trochleoplasty:
- Tibial tubercle transfer is usually the best way to establish a balanced and accurate tracking pattern for the patella in patients with established malalignment;
- Anteromedial tibial tubercle transfer is only needed when a distal patella articular lesion needs to be unloaded at the time of tibial tubercle transfer; and
- Rotational osteotomies and trochleoplasty are useful and effective in extreme cases, but are rarely needed to achieve stability in the majority of patella instability patients.
Lastly, remember early motion is important and nearly eliminates the risk of serious stiffness. Anatomic accuracy, establishing proper tracking and early motion go hand in hand.
John P. Fulkerson, MD, is a clinical professor of orthopedic surgery at the University of Connecticut School of Medicine and practices at Orthopedic Associates of Hartford in Farmington, Conn. He is also president of The Patellofemoral Foundation.
Disclosure: Fulkerson reports he receives royalties from DJO Global and is a patent holder for DJO Global.