Computer-assisted techniques versus conventional guides for component alignment in total knee arthroplasty: a...

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Medical Imaging

Background:

• Optimal prosthesis alignment is crucial for successful total knee arthroplasty (TKA).
• Conventional TKA techniques utilize intramedullary and extramedullary guides for component alignment.
• Variations in alignment can impact patient outcomes and revision rates.

Purpose of the Study:

• To compare the accuracy of component alignment in TKA using computer-assisted surgery (CAS) versus traditional intramedullary (IM) and extramedullary (EM) guides.
• To evaluate the impact of different alignment techniques on radiographic outcomes and operative times.
• To determine the most accurate method for achieving optimal implant positioning in TKA.

Main Methods:

• A randomized controlled trial involving 107 patients undergoing TKA.
• Patients were assigned to three groups: CAS, IM guides for both femur and tibia, or IM guide for femur with EM guide for tibia.
• Alignment was assessed using hip-to-ankle radiographs and CT scans three months post-surgery.

Main Results:

• CAS group showed significantly less coronal tibiofemoral malalignment (1.91°) compared to EM (3.22°) and IM (2.59°) groups (p=0.007).
• A greater deviation (>3°) was observed in 19% of CAS patients versus 38% (EM) and 36% (IM) (p=0.022).
• CAS increased operative time (107 min) versus IM (80 min) and EM (83 min) (p<0.0001); no outcome differences between IM and EM groups.

Conclusions:

• Computer-assisted total knee arthroplasty provides significantly improved implant alignment compared to conventional IM or EM guide techniques.
• This enhanced accuracy in alignment, as verified by radiography and CT, supports the use of CAS in TKA.
• The findings contribute to the evidence base favoring CAS for superior radiographic outcomes in total knee replacement.