Simplifying Sacroiliac Joint Arthrodesis Using MIS Fusion Implants
J. Jay Halki, M.D., Mark A. Reiley, M.D., Leonard M. Rudolf, M.D., Arnold Graham-Smith, M.D. Abstract Presented at the North American Spine Society 2010 Annual Meeting in Orlando, FL (NASS), Oct 2010
Category: NASS 2010, Clinical
SIMPLIFYING SACROILIAC JOINT ARTHRODESIS USING MIS FUSION IMPLANTS
Authors: J. Jay Halki, MD1, Mark A. Reiley, MD2, Leonard M. Rudolf3, MD, Arnold Graham-Smith, MD4
Purpose: According to Bernard and Kirkaldy-Willis (1987), over twenty two percent (22%) of individuals who presented with lower back complaints actually had problems in their sacroiliac joint (SI joint.) Despite the large number of patients with SI joint symptoms, in recent history, most of the treatment focus in the spine has centered on the disc. Orthopedic and neurosurgical residents are rarely taught to consider degenerative SI joint arthritis and/or old SI joint trauma as the cause of the patient’s low back problems. In addition few if any lumbar MRI’s routinely extend below S1 to examine the SI joint. A minimally invasive surgical (MIS) procedure may help to address this significant unmet clinical need.
Figure 1. AP and Lateral x-rays of the Fusion Rod treatment of the SI Joint.
Relevance: In response to the increasing awareness of symptomatic SI joint pathology, an innovative, patented, intramedullary MIS implant to treat the sacroiliac joint (Figure 1) was developed. This procedure requires only a minimal incision and uses a titanium implant. The implants are coated with a porous plasma spray that acts as an interference surface to help decrease implant motion. These implants, because of their size and metallurgy, are able to produce exceedingly strong constructs. A similar system has been used successfully in over 1,000 cases of dysfunctional foot joints.
Diagnostic methods: SI joint diagnoses require appropriate interpretation of a patient’s history, clinical exam, and imaging studies (often hip and lumbar pathology coexist with SI joint pathology). Physical examination for SI pathology includes pain, palpable tenderness of the posterior pelvic SI region, provocative testing (min. 3 positive tests), and the absence of neurologic deficits. Image- guided injection provides confirmation of SI joint pathology. If lidocaine is injected into the joint and symptoms temporarily resolve, then this is excellent confirmation of the diagnosis. Some physicians repeat the injection to reduce the chance of a false positive.
Concomitant abnormalities on a lumbar MRI can cloud the correct diagnosis. However, when physical and laboratory findings point to the SI joint, chronic, degenerative changes in the lumbar spine or bulging discs should not override a diagnosis of SI Joint pathology.
Methods: The MIS surgical procedure is performed under general in the prone position. The 7.0 mm triangular fusion implants are inserted through a 2 to 3 cm incision. The drills, the broaches, and the 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. Post-operatively patients are kept non-weight bearing for 6 weeks, depending on the patient’s pain level and physician recommendation. Routine activities are allowed at 12 weeks after surgery. Radiologic studies include immediately post op films, and 3, 12, and 24 month X- rays. CT is recommended at 3, 12, and 24 months to document implant position, and to observe bone growth across the joint.
Clinical Results: The authors treated the 52 patients included in this report. Patients were tested quantitatively for SI joint symptoms, pre-operatively, at 3, 6,
12, and 24 months (when available). Patients have been able to return to full
and unrestricted activity at three months. Signs of SI joint fusion occur as early as 2 months post-operative, as seen on sagittal CT view (Figure 2). Symptom scales administrated pre-op, 3, 6, and 12 months, showed SI joint symptoms decreased from a pre-op average of 8.2 to 1.2 at 12 months. In response to questioning, 90% of patients indicated they would have the operation again.
Figure 2. Sagittal CT of pelvis shows bone crossing the SI joint 2 months after surgery.
Conclusions: SI dysfunction syndromes (laxity or arthritis) are common. There needs to be a heightened awareness that the SI joint can produce symptomatology. Several treatments available heretofore have shown limited efficacy or moderately severe collateral damage. Rheumatologists and physiatrists need to have an outlet for these previously, unsatisfied patients. In some patients with residual symptoms after hip arthroplasty or lumbar spine
procedures, it may be the SI joint that is the symptom generator. With the advent of a new MIS procedure, the surgeon may now be able to avoid unsuccessful repeat procedures as is often seen in failed lumbar spine surgery syndrome.
1 Department of Orthopaedic Surgery, Northern Nevada Medical Center, Reno, NV, USA
2 Berkeley Orthopaedic Medical Group, Inc., Berkeley, California, USA
3 Department of Orthopaedic Surgery, Alice Peck Day Health Systems, Lebanon, NH, USA
4 Department of Orthopaedic Surgery, Baptist Health of Northeast Florida – South, Jacksonville, FL, USA
Key Words: SI joint, sacroiliac dysfunction, minimally invasive surgical, implant, symptom scales, low back pain, lumbar.
