Michael Payer

Elevated levels of tumor necrosis factor-alpha in periradicular fat tissue in patients with radiculopathy from herniated disc

Study Design. Case-control study. Objective. To determine whether inflammatory cytokines [tumor necrosis factor (TNF)-&agr;, interleukin (IL)-1&bgr;, IL-6 and IL-8] are elevated in tissues intimately surrounding involved nerve roots of patients suffering from radiculopathy form herniated disc (HD). Summary of Background Data. Proinflammatory cytokines are postulated to play an important role in radiculopathy from HD. Although TNF-&agr; has been found in human HD, it is not known whether TNF-&agr; concentrations are increased in symptomatic patients. Epidural fat (EF) is another tissue in close contact with nerve roots. Histologic modifications of EF have been reported in patients with sciatica but concentrations of inflammatory cytokines have never been studied. Methods. Twenty-three lumbar HD along with adjacent EF (EFHD) were harvested from patients with radicular syndrome. As controls, 14 intervertebral discs (IVDs) and 10 samples of EF (EFC) were obtained from patients without radicular syndrome undergoing spine surgery. Tissue explants were incubated ex vivo for 48 hours and the concentrations of cytokines were measured by ELISA in the supernatants. Results were standardized according to tissue weight. Results. All 4 cytokines were found at higher concentrations in EFHD compared with HD (P < 0.001). TNF-&agr; was the only cytokine found in significantly higher levels in EFHD compared with EFC [median, interquartile range 6.6, (1.6–16.3) pg/mL per milligram of tissue vs. 2.3 (1.3–5.0), P < 0.05] and to subcutaneous fat [0.35 (0–2.28), P < 0.001]. No significant increase of either cytokines was found in HD compared with IVD. Conclusion. Higher concentrations of TNF-&agr; were found in EF from patients with radiculopathy from HD compared with patients suffering from other type of back pain. These results support the role of TNF-&agr; in the pathogenesis of radiculopathy from HD.

Posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws.

PurposeC1-C2 instability or painful osteoarthritis are recognised indications for posterior atlanto-axial fixation. In the traditional trans-articular C1-C2 screw fixation, up to 20% of patients cannot have safe placement of bilateral screws in the event of a medially located vertebral artery and a straight screw trajectory in the sagittal plane. The more recently developed C1-C2 fixation technique with individual C1 lateral mass screws and converging C2 pars screws can be employed in case of a medially located vertebral artery and has comparable biomechanical strength. This is a prospective observational study to investigate the advantages, the safety, and the drawbacks of posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws.MethodsTwelve consecutive patients with C1-2 instability (nu2009=u200911) and painful osteoarthritis (nu2009=u20091) underwent a posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws. The average follow-up was 16xa0months and all patients reached the 12-month follow-up.FindingsNo hardware failure occurred in any of the patients. Correct screw placement and construct stability was found in all 12 patients (100%) at 6 and 12xa0months after surgery. Mean neck pain on a visual analogue scale (VAS) was 2.1 at 6xa0months and 2.0 at 12xa0months. Only transient complications were observed: one patient presented with progressive intestinal herniation through the iliac crest scar; one suffered from severe pain at the posterior iliac crest for 3 months and three patients complained of annoying pain/dysaesthesia in the C2 dermatome for 3–6xa0months after surgery.ConclusionThis study confirms that posterior atlanto-axial fixation with polyaxial C1 lateral mass screws and C2 pars screws is a safe and effective surgical option in the treatment of atlanto-axial instability or painful osteoarthritis.

Minimally invasive lumbar spine surgery a critical review

BackgroundMinimal-access technology has evolved rapidly with tubular or percutaneous approaches for decompression and stabilization in the lumbar spine. Potential benefits (smaller scars, diminished local pain, reduced blood loss, reduced postoperative wound pain, shorter hospital stays) have to be weighed against possible drawbacks (reduced orientation, steep learning curve, increased radiation exposure, dependency on technology, cost). While non-comparative case series are often rather enthusiastic, comparative studies and particularly RCTs are scarce and might convey a more realistic appreciation.MethodsA MEDLINE search via PubMed was performed to find all English-language studies comparing open or traditional or conventional with minimally invasive or percutaneous or tubular approaches in degenerative lumbar spine surgery.ResultsOnly nine comparative studies could be retrieved altogether. No clear benefit could be found for minimally invasive procedures in lumbar disc herniation, TLIF, or PLIF. There seems to be a slight advantage in terms of hardware safety in open procedures.ConclusionsThis review, based solely on the very limited number of available comparative studies, shows no relevant benefit from minimally invasive techniques, and a tendency for more safety in open procedures in lumbar disc herniation, TLIF and PLIF.

Acute traumatic central cord syndrome: A comprehensive review

Acute traumatic central cord syndrome (ATCCS) is the most common type of incomplete spinal cord injury, characterized by predominant upper extremity weakness, and less severe sensory and bladder dysfunction. ATCCS is thought to result from post-traumatic centro-medullary hemorrhage and edema, or, as more recently proposed, from a Wallerian degeneration, as a consequence of spinal cord pinching in a narrowed canal. Magnetic Resonance Imaging is the method of choice for diagnosis, showing a typical intramedullary hypersignal on T2 sequences. Non-surgical treatment relies on external cervical immobilization, maintenance of a sufficient systolic blood pressure, and early rehabilitation, and should be reserved for patients suffering from mild ATCCS. Surgical management of ATCCS consists of posterior, anterior or combined approaches, in order to achieve spinal cord decompression, with or without stabilization. The benefits of early surgical decompression in the setting of ATCCS remain controversial due to the lack of clinical randomized trials; recent studies suggest that early surgery (less than 72hours after trauma) appears to be safe and effective, especially for patients with evidence of focal anatomical cord compression.

SPECT/CT in differentiation of pseudarthrosis from other causes of back pain in lumbar spinal fusion: report on 10 consecutive cases.

Purpose: SPECT fused with computed tomography (CT) provides a new approach for more accurate diagnosis of pseudathrosis after spinal fusion procedures. The aim of this study was to compare the findings of SPECT fused with CT (SPECT/CT) with those of CT alone for the diagnosis of pseudarthrosis. Materials and Methods: SPECT and CT of 10 consecutive patients with recurrence of back and/or leg pain and with suspicion of pseudarthrosis on conventional radiologic imaging were analyzed retrospectively. All had previously undergone anterior and/or posterior lumbar fusion techniques. Presence of screw loosening, nonunion through or around the cages, and facet joint degeneration were assessed for diagnosis of pseudarthrosis. Based on SPECT/CT scan findings, the decision of surgical reintervention was made on 6 of 10 patients. The clinical follow-up (mean, 15.6 months; range, 5–29 months) was evaluated according to Macnab criteria (excellent, good, fair, poor). Results: All patients showing screw loosening on CT alone showed also an abnormal uptake on SPECT/CT. SPECT/CT did not show abnormal uptake in 3 of 5 patients who had nonunion through/around the cages on CT alone. SPECT/CT was able to show increased uptake in 6 cases in which CT alone did not show facet joint degeneration. Conclusions: In the lumbar spine, SPECT/CT seems to increase specificity for detection of nonunion of interbody devices compared with CT alone. It is more sensitive than CT to detect facet joint degeneration, and it can detect screw loosening as well as CT. These findings can be helpful for surgeons in planning appropriate surgical revision strategy.

Spontaneous acute spinal subdural hematoma: spontaneous recovery from severe paraparesis—case report and review

Spontaneous idiopathic acute spinal subdural hematomas are highly exceptional. Neurological symptoms are usually severe, and rapid diagnosis with MRI is mandatory. Surgical evacuation has frequently been used therapeutically; however, spontaneous recovery in mild cases has also been reported. We present a case of spontaneous recovery from severe paraparesis after spontaneous acute SSDH, and review the English-speaking literature.

Clinically relevant complications related to posterior atlanto-axial fixation in atlanto-axial instability and their management

BACKGROUNDnThe Magerl transarticular technique and the Harms-Goel C1 lateral mass-C2 isthmic screw technique are the two most commonly used surgical procedures to achieve fusion at C1-C2 level for atlanto-axial instability. Despite recent technological advances with an increased safety, several complications may still occur, including vascular lesions, neurological injuries, pain at the harvested bone graft site, infections, and metallic device failure.nnnMETHODSnWe retrospectively analyzed all patients (n=42 cases) undergoing a Harms-Goel C1-C2 fixation surgery with polyaxial C1 lateral mass screws and C2 isthmic screws at two different institutions between 2003 and 2012 and report clinical and radiological complications. One patient was lost to follow-up. The mean follow-up of the remaining 41 patients was 18.7 months (range 12-90). A clinically relevant complication was defined as a complication determining the onset of a new neurological deficit or requiring the need for a revision surgery.nnnRESULTSnA total of 14 complications occurred in 10 patients (24.4% of 41 patients). Greater occipital nerve neuralgia was evident in 4 patients (9.8%). All but one completely resolved at the end of the follow-up. Persistent neck pain was reported by 3 patients (7.3%), hypoesthesia by 1 patient (2.4%), and anesthesia in the C2 area on both sides in 1 patient (2.4%). Furthermore, a superficial, a deep, and a combined superficial and deep wound infection occurred in 1 patient each (2.4%). One patient (2.4%) had pain at the iliac bone graft donor site for several weeks with spontaneous resolution. A posterior progressive intestinal herniation through the iliac scar was seen in 1 case (2.4%), which required surgical repair. No vascular damages occurred. Altogether, 5/41 patients (12.2%) had a clinically relevant complication including 4 patients necessitating a revision surgery at the C1-C2 level (9.8%).nnnCONCLUSIONSnAtlanto-axial fixation surgery remains a challenging procedure because of the proximity of important neurovascular structures. Nevertheless, on the basis of our current experience, the C1 lateral mass-C2 isthmic screw technique appears to be safe with a low incidence of clinically relevant complications. Postoperative C2 neuralgia, as the most frequent problem, is due to surgical manipulation during preparation of the C1 screw entry point.

Solitary thoracic intradural extramedullary ependymoma

Intradural extramedullary ependymomas of the cervical or thoracic spine are extremely rare. We present a 62-year-old woman with progressive thoracic back pain over 9 months. Magnetic resonance imaging rerevealed a thoracic intradural extamedullary tumour which was surgically removed in total. Histologic examination identified the tumour as ependymoma, WHO Grade II. Our radiological and surgical findings are consistent with the hypothesis that these tumours develop from heterotopic glial tissue pinched off from the neural tube during its closure. Copyright 1999 Harcourt Publishers Ltd.

Accuracy of freehand fluoroscopy-guided placement of C1 lateral mass and C2 isthmic screws in atlanto-axial instability

BackgroundThe C1 lateral mass and C2 isthmic stabilization, as introduced by Goel and Laheri and by Harms and Melcher, is a well-known fixation technique. We present the clinical and radiographic results with freehand fluoroscopy guided C1 lateral mass and C2 isthmic fixation in a consecutive series of 28 patients, evaluating the accuracy of screw placement.MethodsTwenty-eight consecutive patients suffering from post-traumatic and other C1-C2 instability were operated on between 2001 and 2010. Indications for surgery were: trauma (nu2009=u200921 cases), os odontoideum (nu2009=u20091), cranio-verterbal malformation (nu2009=u20091), and arthritis (nu2009=u20093) and idiopathic instability (nu2009=u20092). C1 lateral mass and C2 isthmic screws were placed according to the usual anatomical landmarks with lateral fluoroscopy guidance. All patients underwent a postoperative CT scan. The extent of cortical lateral or medial breach was determined and classified as follows: no breach (grade A), 0–2xa0mm (grade B), 2–4xa0mm (grade C), 4–6xa0mm (grade D), more than 6xa0mm (grade E). Grade A and B screws were considered well positioned.ResultsA total of 56xa0C1 lateral mass and 55xa0C2 isthmic screws were placed. Accuracy of screw placement was as follows: 107 grade A (96.4%), four grade B (3.6%), and no grade C, D or E. Clinical and radiological follow-up showed improvement in symptoms (mainly pain) and stability of the implants at the end of the follow-up.ConclusionsFreehand fluoroscopy-guided insertion of C1 lateral mass and C2 isthmic screws can be safely and effectively performed.

Superficial siderosis of the central nervous system: secondary progression despite successful surgical treatment, mimicking amyotrophic lateral sclerosis. Case report and review.

Superficial siderosis of the central nervous system is a rare disorder with hemosiderin deposition in the spinal and cranial leptomeninges and subpial layer, mostly from repetitive subarachnoid hemorrhage. Progressive sensorineural deafness, cerebellar ataxia, and pyramidal signs comprise the typical clinical presentation. We describe a 47-year-old patient, who showed initial 2-year improvement after successful occlusion of an intradural bleeding source at T4. Secondary progression of symptoms without further bleedings was noted thereafter, with a clinical picture of amyotrophic lateral sclerosis. This case illustrates that the disease may progress secondarily even without re-bleedings, and that secondary progression might be due to a similar pathomechanism as in amyotrophic lateral sclerosis.