The failure of subcategorization of cauda equina syndrome.

The diagnostic sub-categorization of cauda equina syndrome (CES) is used to aid communication between doctors and other healthcare professionals. It is also used to determine the need for, and urgency of, MRI and surgery in these patients. A recent paper by Hoeritzauer et al (2023) in this journal examined the interobserver reliability of the widely accepted subcategories in 100 patients with cauda equina syndrome. They found that there is no useful interobserver agreement for the subcategories, even for experienced spinal surgeons. This observation is supported by the largest prospective study of the treatment of cauda equina syndrome in the UK by Woodfield et al (2023). If the accepted subcategories are unreliable, they cannot be used in the way that they are currently, and they should be revised or abandoned. This paper presents a reassessment of the diagnostic and prognostic subcategories of cauda equina syndrome in the light of this evidence, with a suggested cure based on a more inclusive synthesis of symptoms, signs, bladder ultrasound scan results, and pre-intervention urinary catheterization. This paper presents a reassessment of the diagnostic and prognostic subcategories of CES the light of this evidence, with a suggested cure based on a more inclusive synthesis of symptoms, signs, bladder ultrasound scan results, and pre-intervention urinary catheterization.

Which treatment provides the best neurological outcomes in acute spinal cord injury?

Initial treatment of traumatic spinal cord injury remains as controversial in 2023 as it was in the early 19th century, when Sir Astley Cooper and Sir Charles Bell debated the merits or otherwise of surgery to relieve cord compression. There has been a lack of high-class evidence for early surgery, despite which expeditious intervention has become the surgical norm. This evidence deficit has been progressively addressed in the last decade and more modern statistical methods have been used to clarify some of the issues, which is demonstrated by the results of the SCI-POEM trial. However, there has never been a properly conducted trial of surgery versus active conservative care. As a result, it is still not known whether early surgery or active physiological management of the unstable injured spinal cord offers the better chance for recovery. Surgeons who care for patients with traumatic spinal cord injuries in the acute setting should be aware of the arguments on all sides of the debate, a summary of which this annotation presents.

The diagnostic and prognostic value of artificial intelligence and artificial neural networks in spinal surgery : a narrative review.

In recent years, machine learning (ML) and artificial neural networks (ANNs), a particular subset of ML, have been adopted by various areas of healthcare. A number of diagnostic and prognostic algorithms have been designed and implemented across a range of orthopaedic sub-specialties to date, with many positive results. However, the methodology of many of these studies is flawed, and few compare the use of ML with the current approach in clinical practice. Spinal surgery has advanced rapidly over the past three decades, particularly in the areas of implant technology, advanced surgical techniques, biologics, and enhanced recovery protocols. It is therefore regarded an innovative field. Inevitably, spinal surgeons will wish to incorporate ML into their practice should models prove effective in diagnostic or prognostic terms. The purpose of this article is to review published studies that describe the application of neural networks to spinal surgery and which actively compare ANN models to contemporary clinical standards allowing evaluation of their efficacy, accuracy, and relatability. It also explores some of the limitations of the technology, which act to constrain the widespread adoption of neural networks for diagnostic and prognostic use in spinal care. Finally, it describes the necessary considerations should institutions wish to incorporate ANNs into their practices. In doing so, the aim of this review is to provide a practical approach for spinal surgeons to understand the relevant aspects of neural networks. Cite this article: Bone Joint J 2021;103-B(9):1442-1448.

The cost of consent: why healthcare providers must be compliant with the Montgomery principles.

The cost of clinical negligence in the UK has continued to rise despite no increase in claims numbers from 2016 to 2019. In the US, medical malpractice claim rates have fallen each year since 2001 and the payout rate has stabilized. In Germany, malpractice claim rates for spinal surgery fell yearly from 2012 to 2017, despite the number of spinal operations increasing. In Australia, public healthcare claim rates were largely static from 2008 to 2013, but private claims rose marginally. The cost of claims rose during the period. UK and Australian trends are therefore out of alignment with other international comparisons. Many of the claims in orthopaedics occur as a result of "failure to warn", i.e. lack of adequately documented and appropriate consent. The UK and USA have similar rates (26% and 24% respectively), but in Germany the rate is 14% and in Australia only 2%. This paper considers the drivers for the increased cost of clinical negligence claims in the UK compared to the USA, Germany and Australia, from a spinal and orthopaedic point of view, with a focus on "failure to warn" and lack of compliance with the principles established in February 2015 in the Supreme Court in the case of Montgomery v Lanarkshire Health Board. The article provides a description of the prevailing medicolegal situation in the UK and also calculates, from publicly available data, the cost to the public purse of the failure to comply with the principles established. It shows that compliance with the Montgomery principles would have an immediate and lasting positive impact on the sums paid by NHS Resolution to settle negligence cases in a way that has already been established in the USA. Cite this article: Bone Joint J 2020;102-B(5):550-555.

Surgeon proficiency in robot-assisted spine surgery.

Continuous technical improvement in spinal surgical procedures, with the aim of enhancing patient outcomes, can be assisted by the deployment of advanced technologies including navigation, intraoperative CT imaging, and surgical robots. The latest generation of robotic surgical systems allows the simultaneous application of a range of digital features that provide the surgeon with an improved view of the surgical field, often through a narrow portal. There is emerging evidence that procedure-related complications and intraoperative blood loss can be reduced if the new technologies are used by appropriately trained surgeons. Acceptance of the role of surgical robots has increased in recent years among a number of surgical specialities including general surgery, neurosurgery, and orthopaedic surgeons performing major joint arthroplasty. However, ethical challenges have emerged with the rollout of these innovations, such as ensuring surgeon competence in the use of surgical robotics and avoiding financial conflicts of interest. Therefore, it is essential that trainees aspiring to become spinal surgeons as well as established spinal specialists should develop the necessary skills to use robotic technology safely and effectively and understand the ethical framework within which the technology is introduced. Traditional and more recently developed platforms exist to aid skill acquisition and surgical training which are described. The aim of this narrative review is to describe the role of surgical robotics in spinal surgery, describe measures of proficiency, and present the range of training platforms that institutions can use to ensure they employ confident spine surgeons adequately prepared for the era of robotic spinal surgery. Cite this article: Bone Joint J 2020;102-B(5):568-572.

Macroscopic and histologic analyses of de novo bone in the posterior spine at time of spinal implant removal.

STUDY DESIGN: Case series report. OBJECTIVE: To evaluate the macroscopic and histologic appearance of bone after implantation of bone marrow aspirate on mineralized collagen fiber (Healos) at 12 to 24 months postoperative. SUMMARY OF BACKGROUND DATA: Numerous bone graft substitutes are currently used for spinal fusion. The success of these technologies is usually determined by radiographic visualization at 1-year or 2-year follow-up. Although x-rays and computed tomography scans are among the best tools to identify bone, interpretation of these images can still lead to error. METHODS: Six subjects with prior spinal fusion were reoperated for spinal implant removal. All subjects had reached at least 11-month follow-up from their initial spinal surgery. The graft material used in all fusion sites was bone marrow aspirate with Healos (BMA-H), except in a case where autograft was used on one side and BMA-H on the other. At implant removal, macroscopic appearances of the fusion sites were manually tested, photographed, and biopsies were taken and processed for routine histology. RESULTS: Macroscopic observations were critical to determine presence of mineralized or fibrous tissue. In the site implanted with autograft, fibrous tissue was observed macroscopically. This finding was confirmed by histology. In all sites implanted with BMA-H, solid bone was observed macroscopically. In 1 particular case, the newly formed fusion masses had a rectangular shape, reminiscent of that of the implanted strips. Histologically, BMA-H biopsies revealed mature cortico-cancellous bone. CONCLUSIONS: Published accounts of histologic evaluations of bone graft materials are uncommon, due to ethical and clinical limitations to harvesting tissue samples. Reoperations for instrumentation removal present rare occurrences when biopsies can be performed. In all cases, BMA-H implants resulted in solid, mature bone. These findings provide additional data on the effectiveness of BMA-H as a bone graft substitute for posterolateral fusion.

Facet joint cysts causing cauda equina compression.

Facet joint cysts are commonest at the L4-L5 level and are associated with facet joint degeneration and type III (degenerative) spondylolisthesis. It is extremely rare for facet joint cysts to cause symptomatic cauda equina compression. Three elderly patients presented to us with significant cauda equina compression caused by facet joint cysts. One presented with classic symptoms and signs of a cauda equina syndrome, a second with bilateral lower limb neurologic loss associated with uncontrolled epilepsy, and the third with bilateral leg symptoms as well as an upper limb tremor and fasciculation. The diagnosis was easily made after magnetic resonance scanning in two patients, although in one patient, it was significantly delayed because of his confounding neurologic picture. Lumbar spine surgery (decompression and cyst resection) was successful in resolving symptoms in all three, even though two patients had significant neurologic compromise before surgery. The occurrence of facet joint cysts in older patients can be associated with other degenerative neurologic conditions, and the diagnosis might not be apparent early. We suggest that in older patients who have a mixed picture of central and peripheral neurologic compromise, this diagnosis should be considered and investigation of the whole of the spine, not just the brain and spinal cord, should be undertaken.

Avascular necrosis of the femoral head after surgery for lumbar spinal stenosis.

STUDY DESIGN: Case report. OBJECTIVE: To report a previously undescribed complication of lumbar spinal surgery under prolonged hypotensive anesthesia. BACKGROUND DATA: Avascular necrosis of bone most commonly affects the femoral head. The etiology of the condition is understood in only 75% of cases. There have been no prior reports of this condition following lumbar spine surgery carried out under hypotensive anesthetic. METHODS: Notes review, clinical examination, plain radiographs, and magnetic resonance imaging diagnosed three patients who developed avascular necrosis of the femoral heads (five joints in total) after surgery for lumbar spinal stenosis. All three were treated with total hip replacement (five joints), and the diagnosis of avascular necrosis was confirmed in two by histopathological examination. RESULTS: All three patients have recovered full mobility following hip replacement surgery. None had any residual symptoms of lumbar spinal stenosis or hip disease, and none of them had shown any clinical evidence of avascular necrosis in any other bone. CONCLUSIONS: The development of avascular necrosis of the femoral heads following surgery for spinal stenosis may be due to hypotensive anesthesia, prone positioning on a Montreal mattress, or a combination of the two. Careful intraoperative positioning may reduce the risk of this occurring after spinal surgery. However, close postoperative surveillance and a high index of suspicion of worsening hip pathology in patients who appear to mobilize poorly after lumbar spinal surgery may be the only method of early detection and treatment for this condition.