Anatomic cementless total hip replacement: design considerations and early clinical experience

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Total hip arthroplasty (THA) aims to restore function and alleviate pain.
• Thigh pain and limp are common early complications following THA.
• Cementless femoral components are increasingly used, but their impact on early symptoms requires evaluation.

Purpose of the Study:

• To prospectively evaluate the efficacy of anatomically designed cementless femoral stems in reducing early thigh pain and limp after total hip arthroplasty.
• To assess the functional outcomes and radiographic findings associated with this implant type.

Main Methods:

• A prospective study of 102 uncemented total hip arthroplasties using anatomic femoral components in 96 patients.
• Follow-up averaged 35 months, with clinical assessment via Harris Hip Score (HHS) and standardized radiographs.
• Primary diagnoses included osteoarthritis, traumatic arthritis, inflammatory arthritis, hip dysplasia, and avascular necrosis.

Main Results:

• The average Harris Hip Score improved significantly from 47 pre-operatively to 93 at final follow-up.
• Incidence of thigh pain and limp was low (3.5% at one year, decreasing to 1.9% at final follow-up).
• Radiographic findings included calcar rounding (75%), pedestal formation (40%), and distal cortical hypertrophy (20%); no endosteal erosions were observed.

Conclusions:

• Anatomically designed cementless femoral components provide satisfactory early pain relief and functional improvement in younger, active patients undergoing total hip arthroplasty.
• The implant demonstrates a low incidence of early thigh pain and limp.
• Radiographic changes are common but generally not associated with adverse outcomes.