DISTAL FEMORAL VARUSING FOR OSTEOARTHRITIS OF VALGUS KNEE: A LONG-TERM FOLLOW-UP

Single Cut Distal Femoral Varus Osteotomy (SCFO): A Preliminary Study

BACKGROUND

Genu valgum usually originates from a deformity of distal femur that is often corrected by distal femoral varus osteotomy. The osteotomy includes both components of angulationcorrection and translation because the site of osteotomy is not commonly at the apex of deformity. Improvement of patellar tracking not only depends on valgus correction, but also it may be partially due to centralization of the trochlear groove under the femoral anatomical axis (FAA).We asked whether we could accurately correct the deformities based on our preoperative goals for the correction of the mechanical axis and centralization of the trochlear groove under the FAA by using a single bone cut.This study describes a new lateral single cut distal femoral osteotomy (SCFO) that enables concurrent correction of angulation and translation.

METHODS

This study was done on 12 young adult patients with femoral juxta-articular genu valgum deformity using SCFO. The average age at operation was 21 years (range: 16-25). SCFO is a type of closing-opening distal femoral osteotomy that corrects the valgus deformity of the distal femur while the translation of the distal fragment is done using one oblique cut. It centralizes the trochlear groove under the FAA. We compared the pre and postoperative radiographic and clinical variables including mechanical tibiofemoral angle, knee range of motion (ROM), International knee documentation committee (IKDC) score and the time to union. Mean follow-up of the patients was 24 months.

RESULTS

The average mechanical tibiofemoral angle improved from 16 degrees (10-23) to 1 degrees (-2 to +2). IKDC subjective score slightly improved from preoperative (65) to 2-year follow-up (71). Centralization of the trochlea was achieved in all patients.

CONCLUSION

SCFO can be a reasonable alternative for correction of the distal femur genu valgum deformity. It can centralize the patellar groove under the FAA with satisfactory clinical outcomes.

Physical activity after distal femur osteotomy for the treatment of lateral compartment knee osteoarthritis

PURPOSE

Distal femoral osteotomy (DFO) is the preferential treatment for the symptomatic osteoarthritis of the lateral compartment of the knee in young active patients. The objective of this study is to evaluate the physical activity and functional outcome of a group of patients presenting with lateral compartment osteoarthritis of the knee prior to and after a DFO for correction of genum valgum.

METHODS

Twenty-six patients who had been submitted to complete V-shaped distal femoral osteotomy were evaluated after a mean follow-up period of 48 months by interview and questionnaire. Functional and physical activities were scored according to published rating systems.

RESULTS

Twenty-two (84.6 %) patients were very satisfied or satisfied (mean satisfaction 2) with the outcome of surgery and 88.5 % of the patients had normal work duties after surgery without limitation or decline in performance. The preoperative median level for physical activity according to the Tegner activity level was 3(2-7), while the median postoperative level was 3 (1-7) (n.s.) 57.7 % had resumed physical activities at preoperative levels: some patients had increased the number and type of exercises. According to Lysholm score, the mean preoperative score for physical performance was 53.1 ± 16.2 while the mean postoperative score had increased to 77.3 ± 16.7 (p < 0.05).

CONCLUSION

Based on this study, distal femoral osteotomy allowed the resumption of physical activities for individuals with symptomatic osteoarthritis of the lateral compartment of the knee, resulting in improvements in clinical conditions and, consequently, in their daily working and recreational activities.