Technique of THR

Indications of Op THR

• OA – Pain, Disability, ROM• AVN• Fr NOF• Fr acetabulum• Tumours

Contraindications

• Recent Sepsis (?Remote)• Neuropathic joint• Weak Abductors/ myopathy• Stable arthrodesis

Type of Prosthesis

• Un cemented• Cemented• Hybrid

Types of Prosthesis

• Unconstrained• Semi-constrained• Fully constrained

Pre-Op Workup

• Patient• X-rays• Instruments• OT

Pre-Op Workup - Patient

• Co-morbidities• Fitness for anaesthesia• Anticoagulant therapy• Skin Condition• Pre-Op deformities• Pre-Op ROM

Pre-Op Workup –X rays

• Hip AP & lateral View• Pelvis AP view• CT Scan in Fr acetabulum/ Fr dislocation hip• Templating• Size & cuts

X rays

Fr NOF

1 Yr post injury2 Month after injury

AVN Hip

Posterior dislocation

GCT Femoral Neck

Pre-Op Workup Instruments

• Op technique brochure• Practice on saw bone• Dry run

Instruments

Instruments - Advantage

• Acetabular positioner

Trial handle

Pre-Op Work up -OT

• Sterilization• OT • Laminar flow• ORAs • Visitors

Surgery

• Position• Incision• Exposure

Exposure

• Dislocation of hip• Osteotomy of neck• Removal of head • Capsular excision• Placement of Hohmann’s retractors

Acetabular Preparation

• Removal of osteophytes & soft tissues• Identification of rim and medial wall• Reaming• Peg holes• Trial implants – non cemented implants• Pulse lavage• Cemented acetabular component• Anteversion

Femoral Preparation

• Entry point• Femoral canal preparation• Trial implant & Trial reduction• Pulse lavage• Cement restrictor• Cement gun

Implantation

• Final implants• Neck & head size• Hip reduction• Drain• Closure

Post Op• Position of limb• Antibiotics• Pain relief• Anti-coagulation – Physical/ pharmaceutical• Early mobilization• Discharge • Stitch removal – 2 wk• Walker x4 wk• Stick x2 wk

Early Complications

• Intraoperative fracture of femur• Trochanter Fractures• Dislocation• Infection• Bleeding• DVT & PE• Sciatic Nerve injury

Long Term Complications

• Wear • Loosening• Peri-prosthetic fractures• Late infection

Polyethelyene Wear

• Mechanical - Thickness of liner

• Wear particle in cement bone interface• Metal backing -

Thinner liner - Even weight distribution

Follow Up

• Scoring System• For life• National Registry