To compare the RLLs following single mix and dual mix cementation techniques.
RLLs were more common in the Endoplus group (10/21) compared to the Alloclassic group (8/28). There was no clinical compromise (all had pain free mobility) in these patients and no progression of RLLs was noted.
To determine how long after injury a single photon emission computed tomography (SPECT) scan may remain positive in cases of symptomatic posterior element lumbar stress injuries. SPECT scans can identify posterior element lumbar stress injuries earlier than other imaging modalities. As these lesions evolve and the spondylolysis becomes chronic, the SPECT scan tends to revert to normal even though healing of the defect has not occurred. The aim of this study was to determine how long after initial injury a SPECT scan might remain positive. One hundred and sixty-five patients (85 male, 80 female) between the ages of 8 and 38 years with suspicion of lumbar spondylolysis or posterior element lumbar stress injuries were investigated. All patients underwent plain radiographs, planar bone scintigraphy and SPECT imaging. The duration of symptoms at clinical assessment was recorded. The age, sex, symptom reproduction on flexion or extension, level of sporting activity, and the Oswestry Disability Index both pre- and post-treatment were also recorded. SPECT positive images (hot scans) were depicted as cases and SPECT negative images as controls. Univariate and multivariate analysis was performed. Eighty-five patients (63 male, 22 female) had positive SPECT scans (cases); eighty had negative scans (controls). The mean age at onset of symptoms was 20.2 years for cases and 17.4 years for controls. Bilateral increased uptake on SPECT scan was more common than unilateral. The commonest site for increased uptake was the posterior elements of the fifth lumbar vertebra. Low back pain in extension was more common in SPECT positive cases. The mean time from injury / onset of symptoms to a positive SPECT scan was 7.1 months (range 5.2–9.2 months) and to a negative SPECT scan was 22.5 months (range 16.8–28.4 months). Intense scintigraphic activity in the posterior elements of the lumbar spine was associated with a more recent injury and was concordant with the patient’s history and physical examination. Chronic, un-united spondylolysis was often scintigraphically occult. There was a window of approximately six months from the onset of symptoms to investigation after which the sensitivity of SPECT imaging diminished.
Recent years have seen the popularization of minimally invasive approaches to the spine. However, the use of the balloon assisted retroperitoneal approach has not been widely described, moreover there has been no direct comparison between this mini-ALIF (anterior lumbar interbody fusion) and the conventional open method in the literature. Comparison of peri and intra-operative parameters between the rnini-ALIF (using the balloon assisted dissector and Synframe retractor system) and the open midline approach for single and double level anterior lumbar interbody fusions in order to assess the efficacy of this procedure. An independent retrospective evaluation of 35 patients who underwent single or double level ALIF under the care of the senior author at the University Hospital, Nottingham during the period from 1997 to 2000. The patients were split between those undergoing a mini-ALIF (balloon assisted retroperitoneal dissection) or the conventional approach via a larger midline incision. The groups were matched for age, sex and number of levels. Data was collated from the medical notes with regards to intra-operative blood loss, operative time, intra-operative complications, PCA requirements, time to mobilisation and length of hospital stay. A statistically significant (p=0. 01) reduction in time to mobilisation (mean 2. 1 days vs 3. 9 days) and operative time (mean 175mins vs 265mins) was found for the single level mini-ALIF. This reflects the greater number of L5/SI fusions in this group. The number of vascular injuries was also greater in the approach to L4/5. No difference was found between the two groups for double level procedures. The immediate advantages of a less invasive approach both to the patient and hospital do not appear to be borne out by this study. Cosmesis was not assessed and the long term functional outcome awaits later confirmation.
A radiological and histological analysis of five knee joints after a minimum of 15 years following the implanting of carbon fibre which had been used as a treatment for knee instability was undertaken. All patients underwent Total Knee replacement for secondary osteoarthritis. Histological analysis demonstrated a variable amount of macroscopically visible carbon particles in the synovium, hyaline cartilage and menisci showed . At microscopy these particles were found enveloped by giant cells and lying quiescent with no active inflammatory changes. No intact carbon fibre ligament was noted within the joint, small portion of the old ligament were covered with a thin fibrous layer but there was no evidence of any structure resembling neo-ligament. Extra articularly the carbon fibre was covered with a thick fibrous sheath with no active inflammatory changes inflammation. In the bone tunnels the carbon fibre- bone interface showed an apposition of the bone to the carbon fibre without any interposing fibrous sheath. The histology suggests that carbon fibre bonds directly with the bone without fibrous interposition and that there is no evidence of synovitis changes related to the carbon fibre material. The study suggest that although carbon fibre failed structurally as a ligament replacement it did not cause any significant long term inflammatory pathology.
Conclusion: The immediate advantages of a less invasive approach both to the patient and the hospital do not appear to be borne out by this study. Cosmesis was not assessed and long term functional outcome awaits later review.