PMC3163138_01
Radiological anteroposterior radiographs of the pelvis showing the Burch Schneider metal cage.
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fig1
After six days of pharmacological treatment, the sciatalgic pain was evaluated with a magnetic resonance (MR) which demonstrated L1-L2 and L3-L4 herniated discs, but no specific radicular compression.The radiological evaluation of the prosthesis did not show mobilization or malpositioning of the implant (Figure 1).
The sciatic nerve (A) compressed by fibrotic tissue (B) after the section of the external rotator muscles (C).
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fig2
After the section of the tendon of the external rotator muscles group and of the piriformis muscle, the nerve appeared clearly embedded in a fibrotic tissue (Figure 2).
The sciatic nerve (A) impinging on the metal cage (B).
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fig3
Moreover, a straight relationship between the sciatic nerve and the Schneider ring was found (Figure 3): this relationship caused the compression of the nerve itself on the metallic cage, particularly during the movement of flexion of the hip, which clearly stretched the nerve.
The muscular flap (A) positioned between the sciatic nerve (B) and the metallic cage: (a) preparation of the flap, (b) the flap in its final position.
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fig4
The nerve was carefully released from the fibrotic tissue, and a muscular flap was made using part of the dissected profundus gluteus muscle to allow a nerve glide on the ischiatic bone and on the edge of the Burch Schneider metal cage (Figure 4).