Aims. The aim of this study was to explore risk factors for complications associated with dural tear (DT), including the types of DT, and the intra- and postoperative management of DT. Patients and Methods. Between 2012 and 2017, 12 171 patients with degenerative lumbar diseases underwent primary lumbar spine surgery. We investigated five categories of potential predictors: patient factors (sex, age, body mass index, and primary disease), surgical factors (surgical procedures, operative time, and estimated blood loss), types of DT (inaccessible for suturing/clipping and the presence of cauda equina/nerve root herniation), repair techniques (suturing, clipping, fibrin glue, polyethylene glycol (PEG) hydrogel, and polyglycolic acid sheet), and postoperative management (drainage duration). Postoperative complications were evaluated in terms of dural leak, prolonged bed rest, headache, nausea/vomiting, delayed wound healing, postoperative neurological deficit, surgical site infection (SSI), and reoperation for DT. We performed multivariable regression analyses to evaluate the predictors of postoperative complications associated with DT. Results. In total, 429/12 171 patients (3.5%) had a DT. Multivariable analysis revealed that PEG hydrogel significantly reduced the incidence of dural leak and prolonged bed rest, and that patients treated with sealants (fibrin glue and PEG hydrogel) significantly less frequently suffered from headache. A longer drainage duration significantly increased the incidence of headache, nausea/vomiting, and delayed wound healing. Headache and nausea/vomiting were significantly more prevalent in younger female patients. Postoperative neurological deficit and reoperation for DT significantly depended on the presence of cauda equina/nerve root herniation. A longer operative time was the sole independent risk factor for SSI and was also a risk factor for dural leak, prolonged bed rest, and nausea/vomiting. Conclusion. Sealants, particularly PEG hydrogel, may be useful in reducing symptoms related to cerebrospinal fluid leakage, whereas prolonged drainage may be unnecessary. Younger female patients should be carefully treated when DT occurs. Cite this article: Bone Joint J 2019;101-B:1115–1121

Aims

Non-coding microRNA (miRNA) in extracellular vesicles (EVs) derived from mesenchymal stem cells (MSCs) may promote neuronal repair after spinal cord injury (SCI). In this paper we report on the effects of MSC-EV-microRNA-381 (miR-381) in a rodent model of SCI.

Following studies in 2007-08 comparing cervical discs devices, satisfaction and accuracy of operated and adjacent levels was observed with titanium devices. Patients were followed up and surgical assessments recorded. MRI with 12 patients were first assessed for imaging quality. Two independent radiologists scored twice sagittal and axial T2 – weighted images using the Jarvik four point scale. Statistical analysis was performed on operated and adjacent levels and between devices. Length of surgery, blood loss, approach and time of exposure to radiation were recorded. Patients were followed up at two years. BAGUERA C containing titanium metal allowed satisfactory visualization of the canal, exit foramina, cord and adjacent levels. PCM and PRODISC C visualization was significantly impaired at operated level and in both spinal cord and neural foramina. At adjacent levels, image quality was statistically poorer for those two devices. 6 patients were operated at C5-C6 and 6 at C6-C7. Mean age was 49. Approach was from the right, length of surgery and blood loss were: mean 46 min and 16.25 cc for BAGUERA C; mean 70 min and 27.5 cc for PCM and mean 63 min with 26.25 cc for PRODISC C. Exposure to radiation presented also significant difference between devices. Clinical outcomes reveal similar VAS and patient's satisfaction scores. Titanium device with polyethylene allow for satisfactory monitoring with adequacy in the assessment of neural decompression. BAGUERA C surgical outcomes indicate potential benefits that may be related to technique and simplicity of implantation

Aim. NICE guidance on lumbar total disc replacement (TDR) recommends ongoing audit should be an integral part of disc replacement surgery. We present our ongoing audit data and the extent of problem of patients lost to follow up. Method. 35 patients underwent lumbar TDR surgery over 4.5 years. They were followed prospectively. A database is maintained and ODI and VAS were collected prospectively, including patient satisfaction and any failures. Results. At latest follow up full data was available for 30 out of 35 patients. The mean follow-up was 34 months (range 3-52 months). There were 13 males with a mean age 37.7 years (range 27-62) and 17 females with a mean age of 49.8 years (range 27-62). Surgery was single level in 24 cases and double level in 6 cases. 21 patients rated their outcome as good or very good and 7 as unsatisfactory. There were 2 failures, one secondary to late extrusion of the polyethylene liner (12 months post-surgery) and one early anterior migration of the prosthesis. ODI scores improved by a mean of 28 points (range -4 to 68) whilst VAB scores improved by a mean of 4.9 (range -1 to 9). Five patients had been lost to follow up. One patient migrated out of the area. Two came from out of the area and did not return for follow up after the initial period and two further patients DNAed multiple clinic appointments. Conclusion. We conclude that lumbar disc replacement surgery can provide substantial improvement in pain relief and function. Continued audit of this cohort of patients is essential to comply with NICE guidance. 14% loss to follow up/audit is encountered despite our best effort

Between January 1990 and December 2000 we carried out 226 SB Charité III disc replacements for lumbar disc degeneration in 160 patients. They were reviewed at a mean follow-up of 79 months (31 to 161) to determine the clinical and radiological outcome. The clinical results were collected by an independent observer, who was not involved in patient selection, treatment or follow-up, using a combination of outcome measures, including the Oswestry Disability Index. Pain was recorded using a visual analogue score, and the most recent radiographs were reviewed.

Survival of the device was analysed by the Kaplan-Meier method and showed a cumulative survival of 35% at 156 months when radiological failure was taken as the endpoint. The mean improvement in the Oswestry disability index scores after disc replacement was 14% (6% to 21%) and the mean improvement in the pain score was 1.6 (0.46 to 2.73), both falling below the clinically significant threshold. Removal of the implant was required in 12 patients, four because of implant failure.

These poor results indicate that further use of this implant is not justified.

The purpose of this study was to evaluate whether concerns about the release of metal ions in metal-on-metal total hip replacements (THR) should be extended to patients with metal-bearing total disc replacements (TDR).

Cobalt and chromium levels in whole blood and serum were measured in ten patients with a single-level TDR after a mean follow-up of 34.5 months (13 to 61) using inductively-coupled plasma mass spectrometry. These metal ion levels were compared with pre-operative control levels in 81 patients and with metal ion levels 12 months after metal-on-metal THR (n = 21) and resurfacing hip replacement (n = 36). Flexion-extension radiographs were used to verify movement of the TDR.

Cobalt levels in whole blood and serum were significantly lower in the TDR group than in either the THR (p = 0.007) or the resurfacing group (p < 0.001). Both chromium levels were also significantly lower after TDR versus hip resurfacing (p < 0.001), whereas compared with THR this difference was only significant for serum levels (p = 0.008). All metal ion levels in the THR and resurfacing groups were significantly higher than in the control group (p < 0.001). In the TDR group only cobalt in whole blood appeared to be significantly higher (p < 0.001). The median range of movement of the TDR was 15.5° (10° to 22°).

These results suggest that there is minimal cause for concern about high metal ion concentrations after TDR, as the levels appear to be only moderately elevated. However, spinal surgeons using a metal-on-metal TDR should still be aware of concerns expressed in the hip replacement literature about toxicity from elevated metal ion levels, and inform their patients appropriately.