Comparison Between Anterior and Direct Lateral Approach in Total Hip Arthroplasty

• Muscle damage [ Time Frame: Day of operation and next four consecutive days ] [ Designated as safety issue: No ]
  CK-total is measured direct postoperativly and for the next four consequtive days. CRP is measured the first four postoperative days.
• Pain [ Time Frame: First four postoperative days ] [ Designated as safety issue: No ]
  Pain using Visual Analog Scale and the use of analgetics (converted to opioid equivalent doses) are recorded.
• X-ray assessment [ Time Frame: 3 and 12 months ] [ Designated as safety issue: No ]
  Placement of the acetabular component (inclination and version) and femoral stem (varus/valgus) and migration.
• MRI [ Time Frame: 3 and 12 months ] [ Designated as safety issue: No ]
  A subselection of about 40 patients will undergo MRI-scans preoperatively and after 3 and 12 months to assess tendon- and muscledamage.

In total hip arthroplasty several approaches can be used. The newly introduced minimally invasive anterior approach is supposed to cause less damage to tendons and muscles. At the same time there are reports that there are more complications when this approach is used. The direct lateral approach is the most used in Norway and is well documented. There are however those who postulate that there is to high risk of damage to the gluteus medius causing Trendelenburg gait. In the investigators hospital both the anterior and direct lateral approach is used with good result. The investigators main study hypothesis is that there is no difference between the use of anterior or direct lateral approach i total hip arthroplasty in regards to postoperative function and pain, complications, radiological finds (X-ray and MRI), markers for muscle damage (i.e CK-total) or other clinical outcomes.

• Procedure: Direct lateral approach in total hip arthroplasty
  The use of direct lateral approach in total hip arthroplasty
  Other Name: Hardinge approach
• Procedure: Anterior approach
  The use of anterior approach in total hip arthroplasty
  Other Name: Smith-Petersen approach

• Active Comparator: Direct lateral approach
  Patient operated using direct lateral approach.
  Intervention: Procedure: Direct lateral approach in total hip arthroplasty
• Active Comparator: Anterior approach
  Patient operated using anterior approach.
  Intervention: Procedure: Anterior approach

Inclusion Criteria:

• Clinical and radiological diagnosis of coxarthrosis

Exclusion Criteria:

• Previous surgery on affected hip
• No mental disability preventing follow-up