Minimally Invasive Surgical (MIS) Method For Sacroiliac Joint Arthrodesis - A Case Series Of…
Leonard M. Rudolf, M.D. Abstract Presented at the World Society for Endoscopic Navigated and Minimal Invasive Spine Surgery in Bonn, Germany, May 2011
MINIMALLY INVASIVE SURGICAL (MIS) METHOD FOR SACROILIAC JOINT ARTHRODESIS – A CASE SERIES OF LONG‐TERM FOLLOW‐UP PATIENTS
Author: Leonard M. Rudolf, MD. Lebanon, New Hampshire, USA
Introduction: Historically treatment focus in spine has centered on lumbar pathology. In published literature, 15‐30% of individuals who presented with lower back complaints had SI joint (SIJ) problems. The incidence of SIJ degeneration is 75% in patients with previous L4‐5 or L5‐S1 fusions. SIJ disruptions from MVAs and falls are a major clinical issue. A minimally invasive surgical (MIS) procedure may help to
address this significant unmet clinical need.
Figure 1. AP and Lateral X‐rays of the MIS treatment of the SI Joint.
Relevance: In response to growing awareness of symptomatic SIJ issues, a triangular, titanium, MIS implant (Figure 1) was developed. This procedure requires a minimal incision and fluoroscopic guidance. The implants are coated with a porous plasma spray that creates an interference fit to decrease implant motion. The implants, because of their size, geometry, and metallurgy, provide immediate post‐op fixation accomplishing the goal of traditional open SIJ fusion through an MIS approach.
Diagnosis: There are multiple publications available regarding the most appropriate method for SI joint diagnosis. In this case series, diagnosis include the patient’s history, physical examination, imaging and either a single or multiple image‐guided local anesthetic injections. The physical examination includes local palpations for pain and/or tenderness and a number of provocative tests.
Methods: The MIS procedure is performed under general in the prone position. 7.0 mm triangular implants are inserted through a 2 to 3cm incision. Implant lengths range from 30mm to 55mm in 5mm increments. The drills, broaches, and implants are cannulated to allow precise placement over a guide pin. As a rule, patients are implanted with three MIS implants across the SI joint. However, MIS implant numbers may vary based on the size of the patient.
Analysis: A retrospective analysis shall be presented regarding the usage of the iFuse Implant System in long‐term follow‐up patients at a single center. The data shall reflect patients that have been treated and include follow-up of at least 12‐months and up to 2 years.
The data collected will focus on the following areas:
‐ Diagnostic methods
‐ Demographics
‐ Patient spine history (etiology)
‐ Post‐operative Care
‐ Adverse events
Figure 2. Sagittal CTs of the SI joint at 3, 9 and 12 months after MIS procedure.
Results: This single site has preformed over 60 procedures to‐date, with 22 patients at 12‐months follow‐up and 10 patients at 24‐month follow‐up. At 12‐month follow‐up, the relative efficacy of the MIS procedure is reflected in an average decrease in pre‐operative symptoms of 55%. 82% of treated patients indicate they would have the MIS procedure again. This early analysis shows high patient satisfaction and CT‐imaging evidence of bone growth at the bone‐implant interface as seen in Figure 2.
Learning Objectives: 1. The SIJ is a relatively common cause of low back issues. 2. Residual symptoms following lumbar fusion may be from the SIJ. 3. There is now an MIS procedure available as an SIJ treatment option.
Key Words: SI joint, sacroiliac dysfunction, minimally invasive surgical, implant, symptom scales, low back pain, lumbar.
