Alternating Layers of Morselized Allograft and Injectable Ceramic Bone Graft Substitute in Acetabular Reconstruction: A Novel 'Sandwich' Technique

Background

Impaction of morselized allograft is an appealing procedure for addressing the bone defects. However, concerns remain about its suitability for massive defects. We used a novel "sandwich" technique by impacting the morselized allograft in layers with an intervening layer of injectable bone graft substitute for restoring bone defects during acetabular reconstruction in total hip arthroplasties.

Methods

From August 2015 to June 2017, 17 revisions, 4 rerevisions, and 3 complex primary total hip arthroplasties were operated by this novel technique. Postoperatively, serial X-rays were evaluated at regular intervals. Clinical and functional outcomes were assessed by the Harris hip score. To examine if introducing an injectable bone substitute into allograft stock increased its load-bearing capability, simulated mechanical testing using Synbone samples was conducted in the laboratory.

Results

The mean Harris hip score significantly improved from 54.6 preoperatively to 86.8 at the latest follow-up. Graft incorporation was seen in all the cases. There was no evidence of component migration or loosening as compared to the X-rays at 3 weeks and 3 months in all the cases. With revision of component as end point, the survivorship was 100% at 82 months. The mechanical testing reported a higher capability of allograft samples when compared to those without bone substitutes.

Conclusions

Our data confirms that the use of the "sandwich" technique is a reliable option for major acetabular reconstruction. Early weight bearing is a significant value addition, and short-term results confirm good clinical and functional outcome. Longer follow-up is necessary to assess the status of the construct in the long term.

Acetabular Screw in Close Proximity to the Posterior Branch of the Internal Iliac Artery in Revision Hip Surgery with Intrapelvic Migration of Acetabular Component: Preoperative Placement of a Fogarty Catheter in the Internal Iliac Artery (Case Report)

Revision of an intrapelvic migration of the acetabular component of a total hip is a challenging surgery due to the risk of injury to the pelvic viscera. The primary concern is vascular injury due to the risk of mortality and limb loss. The researchers present one case where the acetabular screw was near the posterior branch of the internal iliac artery. A Fogarty catheter was placed in the internal iliac artery preoperatively, and the amount of fluid to inflate the catheter and completely block the artery was determined. The catheter was kept in a deflated condition. The hip reconstruction was performed, and there was no incidence of vascular injury during the procedure; hence, the Fogarty catheter was removed postsurgery. The placement of a Fogarty catheter in the at-risk vessel provides the freedom to proceed with the hip reconstruction through the standard approach. In case of an inadvertent event of a vascular injury, it can be inflated with the predetermined amount of saline to check the bleeding until the vascular surgeons take over the case.