CASE 37: Revision of the femoral stem for pain and malalignment causing impingement
The Story
“A 48-year-old male presented with left groin pain.
At 26 he had injured his left rectus femoris playing football, requiring reconstruction. This started to cause him pain in his late 30’s and he was treated with femoral nerve neurolysis. This provided partial relief.
In 2011 he had a left Birmingham hip resurfacing completed which also provided partial pain relief.”
The Investigation
The patient presented with an audible click in his left hip with flexion and internal reduction and the inability to adduct fully. He had a normal gait and was able to straight leg raise however this caused pain.
An injection of local anaesthetic relieved his pain for 24 hours.
He had a CRP of 2.2mg/L and an ESR of 16mm/H ruling out infection and his blood metal ion levels were satisfactory.
The Evidence
Pre-operative anteroposterior radiograph shows satisfactory sizing, positioning and fixation of the left Birmingham hip resurfacing.
An MRI scan revealed rectus femoris problems, which are long standing, but also psoas atrophy.
The Diagnosis
The diagnosis was of left groin pain secondary to psoas tendonitis due to the psoas tendon rubbing on the inferior margin of the hip resurfacing head.
The Plan
Revision of the Birmingham hip resurfacing, reducing the size of the femoral head to 36mm while maintaining stability with a longer neck.
A Corail femoral stem was used with a ceramic head. A Pinnacle Gription socket was used with a polyethylene liner and 3 screws for initial stability.
Stage One Outcome
Post-operative AP radiograph shows a well-fixed, well-positioned and well-sized total hip replacement.
The patient is very happy with the outcome of the surgery. His left hip is functioning very well and his psoas tendon function is improving.
The Verdict
Anterior impingement can lead to psoas tendonitis. This is rectified by replacing a large diameter head with a smaller one, while maintaining stability by increasing the femoral offset.
