The Incidence of Venous Thromboembolism in Patients Undergoing Anterior Lumbar Interbody Fusion: A Proposed Thromboprophylactic Regime.

OBJECTIVE: To determine the safety and efficacy of the proposed venous thromboembolism (VTE) prophylaxis regime in patients undergoing anterior lumbar interbody fusion (ALIF) surgery. BACKGROUND: Deep vein thrombosis (DVT) and pulmonary embolism (PE) are recognized complications after spine surgery, with rates in the literature ranging from 0% to 14% with some form of prophylaxis. Pharmacological thromboprophylaxis can cause postoperative bleeding and hematomas, which can result in significant neural compromise or permanent injury, and wound complications. ALIF surgery involves the handling and compression of major abdominal vessels during surgery and this adds to the risk of both arterial thrombosis and VTE. METHODS: A retrospective review of data, which were prospectively collected to evaluate the incidence of VTE in 200 consecutive patients undergoing ALIF following our VTE prophylaxis protocol. All patients had low molecular weight heparin, tinzaparin 4500 units subcutaneously on the evening before surgery, then daily for 3 to 5 days, then aspirin (acetylsalicylic acid) 150 mg daily plus lansoprazole 30 mg daily for 4 weeks after surgery. All patients had intermittent pneumatic compression of their calves and thighs intraoperatively and for 24 hours postoperatively then had early mobilization and thromboembolic deterrent stockings for 6 weeks. RESULTS: There was no incidence of any symptomatic VTE in the any of the 200 patients and no loss to follow-up. There was a 0% incidence of injury to the iliac vessels, symptomatic arterial occlusion, wound hematoma, major intraoperative bleeding, need for transfusion, symptomatic GI bleed, or retroperitoneal hematoma requiring intervention. CONCLUSIONS: The proposed VTE prophylactic regime is safe and efficacious and may decrease the incidence of symptomatic VTE in patients undergoing an ALIF procedure, and despite the use of chemical thromboprophylaxis, there is no evidence of bleeding complications as a result of using this regime. LEVEL OF EVIDENCE: 4.

Significantly improved outcomes with a less invasive posterior lumbar interbody fusion incorporating total facetectomy.

STUDY DESIGN: Original study. OBJECTIVE: Prospective comparison of clinical outcomes after a standard posterior lumbar interbody fusion (ST-PLIF) and after a limited exposure PLIF incorporating total facetectomy (LI-PLIF). SUMMARY OF BACKGROUND DATA: Most groups have reported significantly improved clinical outcomes after ST-PLIF. To our knowledge, however, a comparison of outcomes between ST-PLIF and the LI-PLIF that we herein describe has not been reported before. METHODS: Patients were included who had suffered chronic low back pain for a minimum of 2 years that was unresponsive to conservative treatment. N = 114 consecutive patients underwent ST-PLIF, whereas n = 209 underwent LI-PLIF. All patients underwent pre- and postoperative evaluations for Oswestry Disability Index (ODI), short-form 36 (SF-36), and visual analogue scores (VAS). The minimum follow-up for either group was 2 years. RESULTS: There was a significant improvement in the ODI (22.5 +/- 1.0, P < 0.001), VAS for back pain (3.8 +/- 0.1, P = 0.003), VAS for leg pain (4.0 +/- 0.2, P = 0.002), and SF-36 for bodily pain (14.7 +/- 0.9, P = 0.012) after ST-PLIF. However, there was a significantly greater improvement in all scores after LI-PLIF: ODI (28.8 +/- 1.4 vs. 22.5 +/- 1.0, P < 0.001), VAS for back pain (5.4 +/- 0.2 vs. 3.8 +/- 0.1, P = 0.001), VAS for leg pain (5.1 +/- 0.2 vs. 4.0 +/- 0.2, P < 0.001), and SF-36 for bodily pain (18.5 +/- 0.8 vs. 14.7 +/- 0.9, P = 0.003). There was a significantly shorter duration of hospital stay after LI-PLIF (2.24 +/- 0.057 days) than after ST-PLIF (4.04 +/- 0.13 days) (P = 0.005). Operative complications occurred in 19.3% of ST-PLIF and in 6.7% of LI-PLIF. CONCLUSION: Clinical outcomes were significantly improved after both ST-PLIF and LI-PLIF. However, outcomes were significantly better after LI-PLIF than after ST-PLIF. Significantly shortened hospital stay with LI-PLIF probably reflected the "less invasive" technique per se. Significantly better clinical outcomes with fewer complications after LI-PLIF, however, potentially reflected maneuvers singular to LI-PLIF: (1) preservation of posterior elements, (2) avoidance of far lateral dissection over the transverse processes, (3) bilateral total facetectomy, (4) fewer neurologic complications, and (5) avoidance of iliac crest autograft. LI-PLIF is therefore recommended over ST-PLIF.

The precision and accuracy of templating the size of unicondylar knee arthroplasty.

In trauma and joint arthroplasty, preoperative templating is an important step that can help in the selection of implant size, position and alignment. Although the precision (reproducibility) of templating in unicondylar knee arthroplasty has been assessed previously, the accuracy has never been studied. Our aim is to assess the precision and accuracy of using the templating system for one commonly used unicondylar knee arthroplasty, ALPHANORM design (Alphanorm Medizintechnik, Germany). Eight observers used the templating system to estimate the size of the unicondylar knee prosthesis ALPHANORM in 29 randomly selected patients with osteoarthritis. The observers, who all were orthopaedic surgeons with two different levels of experience, worked independently and repeated their measurements 2 weeks later. All the patients subsequently underwent unicondylar knee replacements, and the actual size of the femur and tibia was assessed intra-operatively without any knowledge of the template sizes. Our results revealed a high level of intra-observer reproducibility. However, the inter-observer reproducibility and the accuracy all were poor.