What's New in Spine Surgery

The impacts of waiting for surgical correction of Adolescent Idiopathic Scoliosis and its repercussions for publicly funded health systems: systematic review

PURPOSE

To investigate, through a systematic review, the impact of the waiting time for Adolescent Idiopathic Scoliosis (AIS) surgical correction from the point of view of deformity evolution, treatment cost, and quality of life.

METHODS

PubMed, Embase, LILACS, SciELO, Scopus, Web of Science, LIVIVO, and Cochrane Library databases were searched by two researchers to select the articles. The eligibility criteria were: Patients diagnosed with AIS with indication for surgical correction and submitted to waiting lists until treatment. The risks of bias were evaluated using the Risk Of Bias In Non-randomized Studies-Interventions (ROBINS-I) tool, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was used to classify the level of the evidence for each outcome. The summary of the available evidence is presented in a narrative synthesis.

RESULTS

Six observational studies were included. In a Canadian study, the primary outcome was the need for additional spine surgery in patients who had to wait more than three months due to spine deformity progression. American researchers presented a sample of premenarcheal and skeletally immature patients with AIS showing increased Cobb angle and attributed this to a six-month waiting for the surgical treatment. Another study included 177 patients with AIS with a mean waiting time of 225.7 days. There was a worsening average of 7.7° ± 8.6° in Cobb angle, and there was a change in surgical plan in 28 patients, which increased surgical time. Studies that evaluated the treatment cost showed significantly higher mean costs in those who waited longer than six months. Regarding the quality of life, while waiting for surgery, a retrospective study found that patients who underwent surgery earlier showed better results in a questionnaire that assessed their quality of life compared to those who were still waiting.

CONCLUSION

Observational studies show that, in individuals who are on waiting lists for AIS surgery, there is a worsening of the spinal deformity (substantial evidence), an increasing cost of treatment (moderate evidence) and it may negatively impact patients' quality of life (insufficient evidence). Performing better methodological quality studies to investigate these outcomes can violate good research practices since randomized clinical trials on this subject have ethical limitations to be carried out.

TRIAL REGISTRATION

The authors declare that the systematic review protocol was registered at the international prospective register of systematic reviews (PROSPERO), CRD42020212134, and it was accepted for publication.

Traumatic Brown-Séquard syndrome: modern reminder of a neurological injury

Brown-Séquard syndrome (BSS) presents as an ipsilateral loss of motor function, proprioception and vibratory sensation accompanied by contralateral pain and temperature loss two to three levels below the level of the injury. It is one of the syndromes associated with incomplete transection of the spinal cord. Classic BSS is rare as most patients present with mixed neurological deficits related to damage of the spinal cord and surrounding structures. BSS remains prevalent in areas with high trauma burden, where assaults with sharp weapons are common. We present the case of a man aged 38 years who sustained a stab injury to the left back. BSS was diagnosed. He underwent removal of the weapon in the operating room and had an uneventful recovery to near baseline functional level after a course of rehabilitation. Despite being a rare aetiology, BSS continues to be an excellent reminder to trauma providers of the anatomy and physiology of neuroanatomical tracts.

Innovation and New Technologies in Spine Surgery, Circa 2020: A Fifty-Year Review

Spine surgery (lumbar, cervical, deformity, and entire spine) has increased in volume and improved in outcomes over the past 50 years because of innovations in surgical techniques and introduction of new technologies to improve patient care. Innovation is described as a process to add value or create change in an enterprise's economic or social potential. This mini review will assess two of three assessments of innovation in spine surgery: scientific publications and patents issued. The review of both scientific publications and issued patents is a unique assessment. The third assessment of innovation: regulatory clearances of medical devices and equipment for spine surgery and their evolution over time, will also be discussed.

Principles of Antibiotic Prophylaxis in Total Joint Arthroplasty: Current Concepts

Infection is a rare, serious complication following total joint arthroplasty and constitutes a considerable emotional and financial burden for patients, surgeons, and healthcare systems. Prevention of surgical site and periprosthetic joint infections is crucial. This requires knowledge of the microorganisms that commonly cause these infections, including Staphylococcus species. Selection of the appropriate antibiotic regimen to treat infection remains controversial, but cefazolin and cefuroxime are the most commonly recommended antibiotics for prophylaxis. Appropriate timing of administration before surgery, with redosing performed as needed, can help to ensure optimal antibiotic concentration during surgery. Given the increasing evidence that S aureus colonization is a risk factor for periprosthetic joint infection, an exploration of the potential benefits of preoperative S aureus carrier screening and decolonization protocols is warranted. The use of antibiotic-loaded bone cement in primary total joint arthroplasty and antibiotic powder at wound closure are other controversial topics that require additional research.

Evaluation of posterolateral lumbar fusion in sheep using mineral scaffolds seeded with cultured bone marrow cells

The objective of this study is to investigate the efficacy of hybrid constructs in comparison to bone grafts (autograft and allograft) for posterolateral lumbar fusion (PLF) in sheep, instrumented with transpedicular screws and bars. Hybrid constructs using cultured bone marrow (BM) mesenchymal stem cells (MSCs) have shown promising results in several bone healing models. In particular, hybrid constructs made by calcium phosphate-enriched cells have had similar fusion rates to bone autografts in posterolateral lumbar fusion in sheep. In our study, four experimental spinal fusions in two animal groups were compared in sheep: autograft and allograft (reference group), hydroxyapatite scaffold, and hydroxyapatite scaffold seeded with cultured and osteoinduced bone marrow MSCs (hybrid construct). During the last three days of culture, dexamethasone (dex) and beta-glycerophosphate (β-GP) were added to potentiate osteoinduction. The two experimental situations of each group were tested in the same spinal segment (L4–L5). Spinal fusion and bone formation were studied by clinical observation, X-ray, computed tomography (CT), histology, and histomorphometry. Lumbar fusion rates assessed by CT scan and histology were higher for autograft and allograft (70%) than for mineral scaffold alone (22%) and hybrid constructs (35%). The quantity of new bone formation was also higher for the reference group, quite similar in both (autograft and allograft). Although the hybrid scaffold group had a better fusion rate than the non-hybrid scaffold group, the histological analysis revealed no significant differences between them in terms of quantity of bone formation. The histology results suggested that mineral scaffolds were partly resorbed in an early phase, and included in callus tissues. Far from the callus area the hydroxyapatite alone did not generate bone around it, but the hybrid scaffold did. In nude mice, labeled cells were induced to differentiate in vivo and monitored by bioluminescence imaging (BLI). Although the cultured MSCs had osteogenic potential, their contribution to spinal fusion when seeded in mineral scaffolds, in the conditions disclosed here, remains uncertain probably due to callus interference with the scaffolds. At present, bone autografts are better than hybrid constructs for posterolateral lumbar fusion, but we should continue to seek better conditions for efficient tissue engineering.