The impact of residual varus alignment following total knee arthroplasty on patient outcome scores in a constitutional varus population.

BACKGROUND: Following a total knee arthroplasty (TKA), restoration of the mechanical axis of the lower limb to a neutral position of 0°â€¯±â€¯3° is generally considered the standard of care. Little is known, however, regarding the impact of realignment defined according to the patient's physiologic anatomy on clinical outcome scores. METHODS: The study included 67 knees with a mean age of 65.9 ±â€¯8.3 years with unilateral osteoarthritis (OA) who underwent a primary unilateral TKA for medial end-stage OA. Patients were categorized based on post-operative limb alignment in one of two ways, either based on alignment relative to their contralateral, physiologic side (physiologic), or alignment relative to a neutral axis (neutral). Knee Society Score (KSS), Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC), and the 12-Item Short Form Survey (SF-12) were compared between the two groups. RESULTS: WOMAC Total and subscale scores improved for both groups between the pre- and post-operative time points. SF-12 scores were comparable post-operatively between the groups. WOMAC and KSS total and subscale scores were slightly greater post-operatively in the group not aligned according to their physiologic anatomy (neutral). However, none of these differences reached a level of significance. CONCLUSION: Post-operatively, residual varus and neutral limb alignment lead to comparable clinical outcome scores. In a constitutional varus population with medial end-stage OA, aligning the lower limb during a TKA to a neutral position rather than the patient's native anatomy does not negatively impact self-reported patient outcome scores at the one and two-year time points.

Outcomes of Surgical Management of Supracondylar Periprosthetic Femur Fractures.

BACKGROUND: Fracture location is an important consideration in managing supracondylar periprosthetic femur fractures. The outcomes of locked plating and intramedullary (IM) nail fixation were therefore compared based on fracture location, being above or at/below the total knee arthroplasty (TKA) flange. METHODS: Fifty-seven patients were identified from surgical records as being treated for supracondylar periprosthetic femur fracture with either a locking plate (n = 38) or IM nail (n = 19). Based on fracture location, either above or at/below the TKA flange, both groups were assessed for time to full weight bearing, time to radiographic union, number of postoperative complications, subsequent surgery, transfusion requirements, as well as range of motion, pain, and instability at most recent follow-up. Radiographs were reviewed to assess fracture alignment with comparisons made immediately postoperative to most recent. RESULTS: Mean follow-up for IM nail and locking plate fixation was 13.9 and 15.6 months, respectively. There was no statistical difference between groups in the mean time to fully weight bear, the incidence of postoperative pain, range of motion, use of gait aids, time to full radiographic union, or the overall radiographic alignment of a healed fracture (P > .05). Comparison based on fracture location yielded similar outcomes. Nonunion was only demonstrated in the IM nail cohort, particularly for fractures below the TKA flange (n = 2). CONCLUSION: The use of either IM nail or locking plate fixation for supracondylar periprosthetic fractures provides comparable clinical outcomes. Caution is recommended in using IM nails for fractures below the flange where limited fixation may increase the risk of nonunion.