Cage subsidence-A multifactorial matter!

STUDY DESIGN: Retrospective cohort study OBJECTIVE: Wider cages are associated with improved decompression and reduced subsidence, but variation in cage physical properties limits consistent outcome analysis after thoracolumbar interbody fusion. This study investigated cage subsidence and its relationship to lateral and posterior approaches with a focus on the hypothesis that the larger surface area of lateral cages results in lower subsidence rates. METHODS: This study retrospectively reviewed 194 patients who underwent interbody fusion between 2016 and 2019 with a primary outcome of cage subsidence. Secondary outcomes were cage distribution (patients, approaches, expandability), cage dimensions, t­scores, length of hospital stay, blood loss, surgical time, and pelvic incidence-lumbar lordosis (PI-LL) mismatch. RESULTS: Medical records were reviewed for 194 patients receiving 387 cages at 379 disc levels. Subsidence was identified in 35.1% of lateral cages, 40.9% of posterior cages, and 36.3% of all cages. Lower surface area (p = 0.008) and cage expandability were associated with subsidence risk. Lower anteroposterior cage length proved to be a significant factor in the subsidence of posteriorly placed cages (p = 0.007). Osteopenic and osteoporotic patients experienced cage subsidence 36.8% of the time compared to 3.5% of patients with normal t­scores (p = 0.001). Cage subsidence correlated with postoperative deterioration of the PI-LL mismatch (p = 0.03). Patients receiving fusion augmentation with bone morphogenic protein experienced higher fusion rates (p < 0.01). CONCLUSION: Cage subsidence is a common complication that can significantly impact operative outcomes following thoracolumbar interbody fusion. Low t­scores, smaller surface area, cage expandability, and lower cage length in posterior approaches contribute significantly to cage subsidence.

A prospective randomized peri- and post-operative comparison of the minimally invasive anterolateral approach versus the lateral approach.

There is still controversy as to whether minimally invasive total hip arthroplasty enhances the postoperative outcome. The aim of this study was to compare the outcome of patients who underwent total hip replacement through an anterolateral minimally invasive (MIS) or a conventional lateral approach (CON). We performed a randomized, prospective study of 75 patients with primary hip arthritis, who underwent hip replacement through the MIS (n=36) or CON (n=39) approach. The Western Ontario and McMaster Universities Osteoarthritis Index and Harris Hip score (HHS) were evaluated at frequent intervals during the early postoperative follow-up period and then after 3.5 years. Pain sensations were recorded. Serological and radiological analyses were performed. In the MIS group the patients had smaller skin incisions and there was a significantly lower rate of patients with a positive Trendelenburg sign after six weeks postoperatively. After six weeks the HHS was 6.85 points higher in the MIS group (P=0.045). But calculating the mean difference between the baseline and the six weeks HHS we evaluated no significant differences. Blood loss was greater and the duration of surgery was longer in the MIS group. The other parameters, especially after the twelfth week, did not differ significantly. Radiographs showed the inclination of the acetabular component to be significantly higher in the MIS group, but on average it was within the same permitted tolerance range as in the CON group. Both approaches are adequate for hip replacement. Given the data, there appears to be no significant long term advantage to the MIS approach, as described in this study.

Tartrate-resistant acid phosphatase 5b and C-terminal telopeptides of type I collagen as markers for diagnosis of aseptic loosening after total hip replacement.

INTRODUCTION: Plain radiography, bone scintigraphy, digital subtraction arthrography and various other techniques can be used to evaluate loosening of hip replacements. These methods are associated with radiation exposure and some of them have an increased morbidity. Furthermore, in some cases the results are not conclusive. METHOD: The osteoclast biomarkers tartrate-resistant acid phosphatase 5b (TRAP 5b) and C-terminal telopeptides of type I collagen (CTX) in serum taken from 12 patients with aseptic loosening were measured. Serum samples from 24 other patients, 12 with an intact arthroplasty and 12 without any kind of joint replacement, served as control groups. RESULTS: The serum level of CTX was increased in comparison to the control groups, but the differences were not significant. In contrast, the increase in TRAP 5b in patients with aseptic loosening was highly significant (P < 0.001). A TRAP 5b value of 3.365 U/L was determined as a cut-off value, giving a sensitivity of 83.3% and specificity of 91.7% to differentiate the patients with aseptic loosening from those with an intact arthroplasty. Measurement of serum TRAP 5b may be a clinically relevant assay for monitoring patients after arthroplasty.

Penile metastasis secondary to follicular thyroid carcinoma.

Penile metastases are rare and are considered to reflect end-stage malignant disease. The first case of a follicular thyroid carcinoma metastasizing to the penis is described. Local tumor control and probably enhanced survival was achieved by extended surgery of a previous pelvic recurrence and the penile metastasis and this procedure may be justified in selected cases.

C-myc gene amplification in different stages of oesophageal squamous cell carcinoma: prognostic value in relation to treatment modality.

BACKGROUND: The proto-oncogene c-myc is known to be involved in the regulation of proliferation, apoptosis and cell differentiation. MATERIALS AND METHODS: Amplification of c-myc was determined by means of differential PCR in 77 surgically treated stage I or II oesophageal squamous cell carcinomas (SCC) as well as in 43 locally advanced SCC (cT3-4 cN0-1 cM0) treated by radiochemotherapy and facultatively by surgery. The findings were correlated to overall survival and to response to radiochemotherapy. RESULTS: C-myc gene amplification was present in 8 out of 77 surgically treated SCC (10.4%) and in 13 out of 43 multimodally treated SCC (30.2%). Among the surgically treated tumours, the presence of c-myc amplification was correlated with high proliferative activity (p = 0.0399) but not with overall survival. Among the multimodally treated SCC, c-myc amplification tended to be correlated with response to chemotherapy and response to radiochemotherapy (not significant) whereas no impact on overall survival was found. CONCLUSION: Amplification of c-myc is found more frequently in advanced stages of oesophageal SCC than in early stages. C-myc amplification, however, does not influence the overall survival of oesophageal SCC patients treated either by surgery alone or by multimodal therapy.