Predictors of Clinical Failure after Endoscopic Lumbar Spine Surgery During the Initial Learning Curve.

OBJECTIVE: This study aims to identify clinical factors that may predict failed endoscopic lumbar spine surgery to guide surgeons with patient selection during the initial learning curve. METHODS: This is an Australasian prospective analysis of the first 105 patients to undergo lumbar endoscopic spine decompression by 3 surgeons. Modified MacNab outcomes, visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were utilized to evaluate clinical outcomes at 6 months postoperatively. Descriptive statistics and ANOVA t tests were performed to measure statistically significant (P < 0.05) associations between variables using GraphPad Prism v10. RESULTS: Patients undergoing endoscopic lumbar surgery via an interlaminar or transforaminal approach have overall good/excellent modified MacNab outcomes and a significant reduction in postoperative VAS and ODI scores. Regardless of the anatomic location of disc herniations, good/excellent modified MacNab outcomes and significant reductions in VAS and ODI were reported post-operatively, however, not in patients with calcified disc herniations. Patients with central and foraminal stenosis overall reported poor/fair modified MacNab outcomes, however, there were significant reductions in VAS and ODI scores postoperatively. Patients with subarticular stenosis or an associated spondylolisthesis reported good/excellent modified MacNab outcomes and significant reductions in VAS and ODI scores postoperatively. Patients with disc herniation and concurrent degenerative stenosis had generally poor/fair modified MacNab outcomes. CONCLUSIONS: The outcomes of endoscopic spine surgery are encouraging with low complication and reoperation rates. However, patients with calcified disc herniations, central canal stenosis, or disc herniation with concurrent degenerative stenosis present challenges during the initial learning curve and may benefit from traditional open or other minimally invasive techniques.

How Does Cage Lordosis Influence Postoperative Segmental Lordosis in Lumbar Interbody Fusion.

BACKGROUND: Consideration of sagittal alignment is an integral part of spinal fusion surgery correlating with superior outcomes. Segmental lordosis is an important contributor to sagittal alignment. This study assessed surgical factors influencing segmental lordosis in a 360° fusion model, including cage dimensions, anterior longitudinal ligament resection, facetectomy, and posterior compression. METHODS: Six L3-4 synthetic spinal motion segments were used in a repeated measures design. Each sample was sequentially instrumented with lateral cages of increasing height and angle. Lordosis was assessed from lateral radiographs of intact and each instrumented condition. The effect of anterior longitudinal ligament resection, posterior compression with pedicle screws, and bilateral facetectomy was additionally examined. RESULTS: A linear relationship between segmental lordosis and cage height was found. This effect was greater with the anterior longitudinal ligament divided. In cages of the same anterior height, increased intrinsic cage lordosis did not result in increased segmental lordosis; cages with no intrinsic lordosis resulted in the highest segmental lordosis. In examining this finding, it was shown that posterior cage height had a larger influence on segmental lordosis. Posterior compression with pedicle screws and bilateral facetectomy increased the segmental lordosis by a further 3.4° and 2.6°, respectively. CONCLUSIONS: Cage height was a key factor, with posterior compression further increasing lordosis. The finding that 0° cages results in the most segmental lordosis was an unexpected finding and highlights the importance of appropriate sizing on resulting lordosis. These findings are relevant to cage selection but require further study prior to applying to clinical practice and may influence future cage design.

Spontaneous peritoneal catheter knot formation: A rare cause of ventriculoperitoneal shunt malfunction.

Ventriculoperitoneal (VP) shunting remains invaluable in the management of hydrocephalus. It is a common procedure that can be complicated by shunt malfunction due to infection, blockage and disconnection. Spontaneous peritoneal catheter knot formation causing CSF flow obstruction is a rare phenomenon. We present a case of a 12years old boy with spontaneous knot formation in the peritoneal catheter causing VP shunt obstruction and hydrocephalus.

Comparison of ALIF vs. XLIF for L4/5 interbody fusion: pros, cons, and literature review.

The incidence of lumbar fusion for the treatment of various degenerative lumbar spine diseases has increased dramatically over the last twenty years. Many lumbar fusion techniques have been developed and popularized, each with its own advantages and disadvantages. Anterior lumbar interbody fusion (ALIF) initially introduced in the 1930's, has become a common and widely accepted technique for lumbar fusions over the last decade offering several advantages over standard posterior lumbar interbody fusion (PLIF) or transforaminal lumbar interbody fusion (TLIF). More recently, the lateral trans-psoas approach termed extreme, direct or lateral lumbar interbody fusion (XLIF, DLIF, LLIF) is gaining widespread popularity. The aim of this paper is to compare the approaches, advantages and disadvantages of ALIF and XLIF for L4/5 interbody fusion based on relevant literature.

An intraneural ganglion cyst causing unilateral hypoglossal nerve palsy.

Intracranial ganglion cysts are rare. We report a patient with a rare unilateral hypoglossal nerve palsy caused by an intraneural ganglion cyst. To our knowledge, there are only four reports of ganglion/synovial cysts causing unilateral hypoglossal nerve palsy. Our aim is to present the fifth report, and to compare our findings with the others.

Giant PICA aneurysm presenting as intractable hiccups.

We report a 23-year-old female with rare intractable hiccups caused by a giant posterior inferior cerebellar artery (PICA) aneurysm compressing the medulla oblongata, which resolved after surgical resection of the aneurysm and decompression of the medulla oblongata. We review the literature on lesions in the posterior fossa presenting as intractable hiccups.

Clinical lessons and risk factors from 403 fatal cases of subarachnoid haemorrhage.

Intracranial aneurysm rupture continues to cause high mortality and morbidity. Determining the aetiology, identifying the risk factors and improving diagnostic accuracy are ongoing challenges. We retrospectively reviewed consecutive autopsies over 30 years (1977-2006) in Auckland, New Zealand, and identified 403 cases of subarachnoid haemorrhage to examine these challenges within a fatal case population. Females (67%) outnumbered males. Ruptured posterior circulation aneurysms were frequent (25%). Left ventricular hypertrophy was documented in 45% of cases, with fatty metamorphosis of the liver also prominent (16%). About 6.5% had additional unruptured aneurysm/s. Most patients were sedentary at onset (39% being asleep); 6% were involved in significant physical exertion; 69% were found dead or collapsed; the remaining patients reported headache (27%) or atypical primary symptoms (4%). Warning headache over recent days to months occurred in 38%, among whom misdiagnosis was notable. Our findings regarding warning headache patterns and the range of atypical presentations are aimed at improving clinician discernment in managing this condition.

Factors affecting implant retention in infected joint replacements.

BACKGROUND: There is no standard treatment for infected joint replacements. The options available are varied, and treatment choices may pose problems in relation to both efficacy and cost-effectiveness. METHODS: A retrospective review of 73 patient records identified in our departmental audit database as infected joint replacements treated at Dunedin Hospital between 1990 and 2000 was carried out. The findings were analysed in terms of outcome of primary treatment, final outcome including prosthesis retention and bacteriology. RESULTS: Of the 73 patients (50 hips and 20 knees), the majority (69%) were managed by primary surgical debridement followed by intravenous antibiotics but about one-third (34%) lost their implants because of infection. Retention of implants was higher in acute infections (85-100%) as opposed to late infections (20-50%). The microbiological analysis showed that Staphylococcus and Streptococcus caused the majority (76%) of infections. CONCLUSION: In our series, a patient with an infected joint replacement had an approximately similar 30% chance of retaining the original prosthesis, undergoing a successful revision and having no implants in situ at the end of treatment.