Surgical Correction of Non-traumatic Patella Maltracking. Midterm Clinical Follow-up

BACKGROUND: Patellar instability comprises a group of pathologies that allow the patella to move out of its trajectory within the trochlear groove during walking. Symptomatic patients who need surgery commonly undergo soft tissue procedures such as medial patellofemoral ligament repair to strengthen the ligaments that hold the patella in place. However, soft-tissue repairs may be insufficient in patients suffering from patellar maltracking, which is characterized by an unbalanced gliding of the patella within its route. In these patients, a different approach is advised. We aim to provide the mid-term clinical outcomes of the Fulkerson distal realignment operation in selected patients with non-traumatic patellar maltracking. METHODS: The clinical outcomes of the Fulkerson distal realignment operation performed in 22 knees of 21 patients were evaluated by a self-administered subjective International Knee Documentation Committee (IKDC) score and the Tegner–Lysholm knee scoring scale. RESULTS: Before surgery, the median IKDC score was 52, and the median Tegner–Lysholm score was 56. Following surgery (mean follow-up 48 months, range 24–156), the median IKDC and the Tegner–Lysholm scores were 67 and 88, respectively. The improvement was statistically significant (P=0.001 and P=0.002 for IKDC and Tegner–Lysholm scores, respectively). Associated procedures included patella microfracture due to grade III–IV cartilage lesion (International Cartilage Repair Society grading system) in four patients, retinacular releases in three patients, medial capsular augmentations in two patients, and medial patellofemoral ligament reconstruction in two patients. One patient with Ehlers–Danlos disease required excessive medialization of the tibial tuberosity. Surgery-related complications occurred in three patients. DISCUSSION: Surgical correction of patellar maltracking with Fulkerson distal realignment combined with associated procedures in individual patients was associated with an increase in subjective and functional clinical scores at medium-term follow-up. Particular attention should address pathologies associated with patellar maltracking and managed accordingly. LEVEL OF EVIDENCE: 4c (case series).