Femoral bow predicts postoperative malalignment in revision total knee arthroplasty.
Diaphyseal bowing may compromise axial alignment in revision total knee arthroplasty (TKA). 277 patients undergoing revision TKA were evaluated for coronal bowing and hip-knee-ankle (HKA) axis. The mean femoral bow was 1.52° ± 0.18° varus (-10.1° to +8.4°). The mean tibial bow was 1.25° ± 0.13° valgus (-5.9° to +10°). HKA axis averaged 3.08° ± 0.35° varus preoperatively compared to 0.86° ± 0.25° varus postoperatively. Inter-rater and intra-rater reliability was high. Femoral bow greater than 4° significantly correlated with postoperative HKA axis malalignment (r = 0.402, P = 0.008). 39.7% of patients deviated 3° or greater from a neutral mechanical axis with a significant difference in femoral bow (0.94° ± 0.31°, P = 0.003). Diaphyseal bowing clearly has an important effect on postoperative limb alignment in revision TKA.
Orthopedic Department, Mayo Clinic, Rochester, Minnesota.
Arjun S
AS
Sebastian
Orthopedic Department, Mayo Clinic, Rochester, Minnesota.
Benjamin K
BK
Wilke
Orthopedic Department, Mayo Clinic, Rochester, Minnesota.
Michael J
MJ
Taunton
Orthopedic Department, Mayo Clinic, Rochester, Minnesota.
Robert T
RT
Trousdale
D000843:Ankle Joint / Q000000981:diagnostic imaging; D019645:Arthroplasty, Replacement, Knee / Q000009:adverse effects*; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery*; D060906:Coxa Valga / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery; D018483:Diaphyses / Q000000981:diagnostic imaging; D005269:Femur / Q000000981:diagnostic imaging* / Q000601:surgery; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000601:surgery; D011184:Postoperative Period; D011237:Predictive Value of Tests; D011859:Radiography; D012086:Reoperation / Q000379:methods; D015203:Reproducibility of Results; D013977:Tibia / Q000000981:diagnostic imaging* / Q000601:surgery
axial alignment in revision total knee arthroplasty; coronal bowing; femoral bow; malalignment; revision total knee arthroplasty