42 Years Old Female Patient with Dysplastic Hip

Courtesy: Mr Justin P Cobb, Imperial College London

A 42 years old underwater photographer and ex dancer presented with a painful left hip now preventing exercise. On examination, she was fit and strong with pain on flexion and internal rotation of the hip.

Imaging revealed a dysplastic hip with superior and anterior subluxation and joint space loss (figures 1a and 1b).

Planning using low dose CT1 illustrated that the femoral head was best resurfaced with a 46mm diameter component (figures 2a and 2b).

Fig 2a and 2b: Planned head position and orientation 135 degrees and neutral on neck by means of low dose CT¹

The matching acetabular component could be inserted at 45 degrees of inclination and 15 degrees of anteversion providing good restoration of head coverage without psoas impingement (figures 3a and 3b).

Fig 3a and 3b: Planned cup position and orientation 45 degrees inclination and 15 degrees anteversion by means of low dose CT¹

At operation, the 46mm head was confirmed, maintaining femoral head bone-stock without compromise on the acetabular side. The single use reamer ensured stable press-fit without undue force.

X-rays taken postoperatively show the position and orientation achieved (figures 4a and 4b).

After 3 years the acetabular interface in mature, and both the femoral neck and periprosthetic pelvic bone is well maintained (figures 5a and 5b).

In functional terms, the patient returned to work rapidly, both on land and underwater. Full marks were achieved with the Oxford Hip Score within 6 months after surgery, while substantial functional gains were still captured in the second postoperative year using personalized score Imperial Score, where 100% is the preoperative aspiration for each activity (figures 6a and 6b).