Stand-alone anterior lumbar interbody fusion (ALIF) provides the opportunity to avoid supplemental posterior fixation. This may reduce morbidity and complication rate, which is of special interest in patients with reduced bone mineral density (BMD). This study aims to assess immediate biomechanical stability and radiographic outcome of a stand-alone ALIF device with integrated screws in specimens of low BMD.

Eight human cadaveric spines (L4-sacrum) were instrumented with SynFix-LR™ (DePuy Synthes) at L5/S1. Quantitative computed tomography was used to measure BMD of L5 in AMIRA. Threshold values proposed by the American Society of Radiology 80 and 120 mg CaHa/mL were used to differentiate between Osteoporosis, Osteopenia, and normal BMD. Segmental lordosis, anterior and posterior disc height were analysed on pre- and postoperative radiographs (Fig 1). Specimens were tested intact and following instrumentation using a flexibility protocol consisting of three loading cycles to ±7.5 Nm in flexion-extension, lateral bending, and axial rotation. The ranges of motion (ROM) of the index level were assessed using an optoelectronic system.

BMD ranged 58–181mg CaHA/mL. Comparison of pre- and postoperative radiographs revealed significant increase of L5/S1 segmental lordosis (mean 14.6°, SD 5.1, p < 0.001) and anterior disc height (mean 5.8mm, SD 1.8, p < 0.001), but not posterior disc height. ROM of 6 specimens was reduced compared to the intact state. Two specimens showed destructive failure in extension. Mean decrease was most distinct in axial rotation up to 83% followed by flexion-extension.

ALIF device with integrated screws at L5/S1 significantly increases segmental lordosis and anterior disc height without correlation to BMD. Primary stability in the immediate postoperative situation is mostly warranted in axial rotation. The risk of failure might be increased in extension for some patients with reduced lumbar BMD, therefore additional posterior stabilization could be considered.

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Background

Depression, anxiety, catastrophising, and fear-avoidance beliefs are some of the so-called “yellow flags” that predict a poor outcome in back patients. Many surgeons have difficulty assessing yellow flags, perhaps due to the complexity of existing instruments and time constraints during consultations. We developed a brief tool to allow the systematic evaluation of core flags.

Background

Patient-rated measures are the gold standard for assessing spine surgery outcomes, but there is no consensus on the appropriate timing of follow-up. Journals often demand a minimum 2-year follow-up, but the indiscriminate application of this principle may not be warranted. We examined the course of change in patient outcomes up to 5 years postoperatively.

Purpose

A new approach to the reporting of health outcomes involves assessing the proportion of patients achieving a level of symptoms that they feel they could live with. We evaluated the acceptable level of pain in patients after surgery for lumbar disc herniation (LDH).

Introduction: We present a clinical and radiology follow-up of the uncemented titanium coated monobloc Robert Mathys (RM) Acetabular Component (Mathys AG Bettlach, Bettlach, Switzerland).

The acetabular component is a monobloc hemispherical cup manufactured from Ultra High Molecular Weight Polyethylene (UHMWPE), with a pure titanium particle coated surface. With heat and pressure, the particles are blasted into the polyethylene surface. The coating promote osseointegration. Stability of the cup is provided by 2 anchoring pegs on the weight bearing part on its outer surface. The inclination of pegs and holes diverge by 5 degrees providing a press-fit effect that increases the rigidity of the primary fixation and this is supplemented by screws inserted through the periphery of the cup. Tow cups designs are available, a full-profile and a bevelled cup. In all cases the bevelled cup was used. The purpose of this study was to assess the clinical performance with 15 years of this cup.

Methods: In this study, the status of the uncemented titanium coated RM cup placed in patients who underwent a primary total hip replacement between January 1, 1988 and December 31, 2001 was determined. A total of 1876 cups (1584 patients) were placed in patients with a permanent residence in Berlin. The femoral component was either an uncemented or a cemented stem in an supine lateral approach with either a 28 or 32mm diameter head. The majority of the heads were ceramic and stainless steel.

The diagnosis was osteoarthritis, rheumatic arthritis, femur neck fracture, developmental dysplasia of the hip (DDH). 1034 patients were contacted by telephone. Out of this patients group 539 patients (678 cups) were evaluated by clinical examination (HHS), radiographic investigation and social evaluation by the WOMAC and NHS score. 451 patients who had died unrelated to the operation. Lost of follow up were 65 patients (69 Cups) and 34 patients (48 cups) had to be revised.

Results: The cumulative survival rate of the RM cup is 98.2 percent at 5 years, 97.5 percent at 10 years and 96.9 percent at 15 years. The survival rate in the ceramic head group is 98.7 at 15 years and by using stainless steel head 91.7 at 15 years. Reseaon for re-opertion was in 34 patients aseptic loosening, 8 patients had infection. Dislocation, malpsition and periprosthetik fracture in 2 patients. In the group with clinical evaluation, the HHS was in 80.2 percent of all patients good and ecellent, 9,7 percent had a moderate result and 10,1 percent had a poor result.

Discussion/Conclusion: The low failure rate for loosening demonstrates that this implant has excellent ongrowth and fixation potential. The RM Cup has been shown to function well at up to 15 years post implantation. Its success may in part be due to the one-piece design.