Ogden8 first described the classification system for PTFJ dislocations. The classification system is based on dislocation direction and whether the joint is partially subluxed or dislocated. The classification system is as follows: type 1, atraumatic subluxation; type 2, anterolateral dislocation; type 3, posteromedial dislocation; and type 4, superior dislocation. Anterolateral PTFJ dislocation is the most commonly reported PTFJ dislocation in published literature. This case was classified as a type 2 dislocation given that the patient’s fibular head can be dislocated with manual pressure following an initial traumatic event.
Past instances of PTFJ instability have been managed with closed reduction and protected weight-bearing, as well as with various open reduction techniques.2-7 Surgical reconstruction is commonly considered in chronic cases or if nonoperative modalities have failed. Although PTFJ arthrodesis or fibular head resection has been used as a prior treatment option, the postoperative complications associated with each of these techniques have since caused them to fall out of favor.
The split biceps femoris graft has been successfully used in the soft tissue reconstruction of PTFJ.3,5-7 The soft tissue reconstruction of the PTFJ provides advantages over arthrodesis or fibular head resection because it preserves normal anatomy and avoids secondary stresses to the ankle encountered in the latter procedure. Fibular head resection also presents secondary complications, such as the loss of the biceps femoris and posterolateral corner ligament insertion points.9 Similar to this study, prior works have reported returns to functionality. However, this study represents the longest clinical postoperative follow-up of PTFJ ligament reconstruction. By using a split biceps graft, the insertion point of the biceps on the fibular head is preserved, thus maintaining normal function while still allowing for an easily tubularized graft for anatomic PTFJ ligament reconstruction.
CONSLUSION
We present data for over 5 years of follow-up for our surgical approach to this rare pathology. To the best of our knowledge, this is the first case report of PTFJ instability that was treated surgically and with a long-term follow-up. The patient did not demonstrate loss of knee motion, pain, or peroneal nerve symptoms. Moreover, she was very satisfied with the procedure at the most recent follow-up and had returned to unrestricted activity. The soft tissue stabilization of a chronically unstable PTFJ is a viable treatment modality that provides good results, and future studies should confirm these satisfactory outcomes in the long-term.
This paper will be judged for the Resident Writer’s Award.