Does mechanical filtration of intraoperative cell salvage effectively remove titanium debris generated during instrumented spinal surgery? An in vitro analysis.

BACKGROUND CONTEXT: Instrumented fusion of the spine is a surgery commonly performed to stabilize vertebrae causing pain and to correct anatomic deformities. Such surgery can create substantial blood loss. Autotransfusion is a means to limit homologous blood transfusion in this setting. However, a dilemma is created when the high-speed drill used for bone removal comes in contact with implanted titanium spinal hardware. A clinician at this point is forced to decide between two options: to discontinue autotransfusion to avoid the potential transfusion of titanium fragments while risking blood loss and the need for homologous transfusion or to continue autotransfusion while risking transfusion of titanium fragments back into circulation. PURPOSE: To conclusively identify whether titanium fragments created by a high-speed drill are able to pass through standard autotransfusion microaggregate blood filters. STUDY DESIGN: A positive and negatively controlled experiment with blinded sample analysis. OUTCOMES MEASURES: The presence or absence of titanium alloy on a filter with detection by energy-dispersive X-ray spectroscopy (EDX). METHODS: A mock autotransfusion setup was devised for in vitro filtering. Six investigational and two control experiments were conducted. Titanium fragments generated by a high-speed drill were aspirated with saline and filtered with standard autotransfusion reservoirs and microaggregate blood filters. A final filter with a 1-µm pore size was placed distal to the blood filters. After filtration was complete, this final filter was analyzed using EDX. RESULTS: The presence of titanium was confirmed by EDX on five of six investigational filters. The positive and negative control filters were analyzed by EDX and tested positive and negative, respectively, for titanium. CONCLUSIONS: Standard 40 µm reservoir and blood microaggregate filters do not eliminate the smallest fragments of titanium generated by contact between a high-speed drill and a titanium hardware. The mass of titanium able to elude filtration is very small. The impact of transfusing blood contaminated with such a small mass of titanium is not known.

Comparison of perioperative parameters and complications observed in the anterior exposure of the lumbar spine by a spine surgeon with and without the assistance of an access surgeon.

BACKGROUND CONTEXT: The anterior approach to the spine is becoming an increasingly important avenue to treat spine conditions. Most of the literature reporting on the exposure uses an access surgeon assisting the spine surgeon to expose and prepare the spine for implant. PURPOSE: To compare perioperative parameters and complications in anterior lumbar spine surgery with the exposure performed either by a spine surgeon or a general surgeon. STUDY DESIGN: A retrospective cohort study comparing perioperative parameters and complications of anterior lumbar spine surgery. METHODS: A retrospective review was completed on 96 consecutive patients who underwent anterior spine surgery between Levels L3 and S1 from 1995 to 2008. Patient and surgery characteristics including demographics, comorbidities, perioperative parameters, and complications were logged. In the first 56 consecutive patients, a general surgeon completed the exposure, with an additional patient who later had the exposure performed by a general surgeon because of extensive prior abdominal surgeries. In the next 39 patients, the orthopedic surgeon completed the exposure. RESULTS: When the operation was performed solely by a spine surgeon, the estimated blood loss, operative time, and hospital stay was 204 mL, 2.80 hours, and 3.5 days, respectively. In the procedures completed with the aid of a general surgeon, it was found that the same parameters were 420 mL, 3.93 hours, and 4.7 days, respectively, and statistically significantly less in the group without the assistance of the general surgeon (p=.0007, p=.0003, and p=.0006, respectively). Fewer complications also were observed in that group (p<.00001). The most common complication was an ileus. Major complications including retrograde ejaculation, iliac vein bleeding, peritoneal rent requiring repair, dyspareunia, or scrotal/penile swelling were only observed in the group with the assistance of the general surgeon. CONCLUSIONS: This study indicated that a spine surgeon can successfully and safely carry out the anterior exposure to the spine without the aid of an access surgeon.

The effect of lordosis, disc height change, subsidence, and transitional segment on stand-alone anterior lumbar interbody fusion using a nontapered threaded device.

In this study, we retrospectively evaluated 37 consecutive patients who underwent stand-alone anterior lumbar interbody fusion (ALIF); for indications that included degenerative disc disease, concordant pain on discography, disc space collapse of more than 50%, and failure of nonoperative management for at least 4 consecutive months. Patient demographics, procedural data, and prospective Short Form 36 General Health Survey composite scores were collected. Mean follow-up was 24.2 months. In this cohort of patients with degenerative disc disease, there was no loosening or migration of implants. Stand-alone ALIF using a threaded interbody fusion device provided excellent clinical results and return-to-work rates with few complications. Increased lordosis was associated with increased subsidence and less favorable outcome. Patients with a transitional segment displayed relatively smaller increases in lordosis and better outcomes than patients without a transitional segment.