Purpose
The purpose of the study was to report the functional and radiological outcome following varus osteotomy as a salvage procedure in young to middle-aged patients with patellofemoral arthritis (PFA) and associated valgus malalignment. It was hypothesized that a significant improvement in knee function and reduction in pain would be achieved. Moreover, a low rate of conversion to patellofemoral joint arthroplasty could be observed.
Material And Methods
Patients (< 50 years of age) that underwent varus osteotomy between 08/2012-01/2020 for the treatment of symptomatic PFA and associated valgus malalignment were consecutively included (minimum follow-up: 24 months). Patient-reported outcome measures (PROMs; International Knee Documentation Committee subjective knee form [IKDC]), Visual Analog Scale [VAS] for pain, Tegner Activity Scale [TAS], and satisfaction with the postoperative results (on a 1-10-scale) and weight-bearing whole-leg anteroposterior radiographs were conducted pre- and postoperatively. The change in PROMs and femorotibial angle (FTA) were tested for statistical significance.
Results
In total, 12 patients (13 knees) were included (66.7% female; mean age 33.8 ± SD 6.6 years). In 10 cases, lateral open-wedge distal femoral osteotomies (DFO) were performed, of which 3 cases included a concomitant femoral derotation. Three medial closed-wedge DFOs and one medial closed-wedge high tibial osteotomy were performed. At follow-up (55.3 ± 29.3 months), a significant improvement in knee function (IKDC: 56.4 ± 14.4 to 69.1 ± 11.2, p = 0.015) and reduction in pain (VAS for pain: 3.5 [interquartile range 2.3-5.8] to 0.5 [0-2.0], p = 0.018) were observed. Patients were able to reach their preoperative sporting activity level (TAS: 3.0 [3.0-4.0] to 3.5 [3.0-4.0], p = 0.854) and were highly satisfied with the postoperative result (8.3 ± 1.9). Additionally, a significant correction of valgus malalignment was observed (5.0 ± 2.9° to -.7 ± 3.2°, p < .001). Regarding complications, two re-osteosyntheses were performed due to delayed bone healing and loss of correction. No conversion to patellofemoral arthroplasty occurred.
Conclusion
In patients with symptomatic PFA and associated valgus malalignment, varus osteotomy as a salvage procedure achieved a significant improvement in knee function and reduction in pain. No conversion to patellofemoral joint arthroplasty appeared.