Abstract
Aims
The aim of this retrospective study was to measure and determine variation in VCA between the two limbs in a patient with windswept deformity on preoperative full-length, standing, hip-to-ankle radiographs. We hypothesised that there will be significant difference in VCA between the two limbs of a patient with arthritic windswept deformity and therefore it is necessary to individualise VCA for each limb preoperatively on full-length radiographs during TKA.
Patients and Methods
In this retrospective study, femoral valgus correction angle (VCA) measured on full-length, hip-to-ankle, standing radiographs was compared between the varus and the valgus limbs in 63 patients with windswept deformities who underwent TKA.
Results
The mean VCA in varus knees was significantly higher compared to mean VCA in valgus knees (p=0.002). The VCA was <5° in 40% of valgus knees compared to 6% in varus knees (p=0.0001) whereas VCA was 5°–7° in 73% of varus knees compared to 47% in valgus knees (p=0.0003). There was no difference in the percentage of varus or valgus knees with VCA >7° (p=0.18). A difference in VCA of <3° between the two limbs was seen in 63% of patients, a difference of ≥3° between the two limbs was seen in 18% of patients and 19% of patients had no difference in VCA between the two limbs
Conclusion
Significant difference in VCA is present between the varus and the valgus limbs in most patients withwindswept deformity undergoing TKA.
Clinical Relevance
It may be necessary to individualise VCA for each limb preoperatively on full-length radiographs in patients with windswept deformities in order to minimize error while performing the distal femoral cut during TKA.
