A recent Neurosurgery digest,
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Study Type: Multicentre retrospective case series (n=5; three academic centres)

Key Question: Is the retrosigmoid trans-middle cerebellar peduncle (trans-MCP) approach a safe and effective option for symptomatic intrinsic pontine cavernous malformations outside the originating centre?

Key Findings:

• Gross total resection was achieved in 5/5 patients, with no residual or recurrent lesion on MRI at 4–14 months' follow-up.
• Postoperative neurological morbidity occurred in all five patients but was mainly transient. Residual deficits were minor (mild ataxia, facial hypoaesthesia, dysarthria, vertigo).
• Median mRS improved from 4 (range 1–4) pre-operatively to 1 (range 1–2) at follow-up.

Clinical Relevance: Provides early independent evidence supporting trans-MCP access for selected deep pontine lesions, relevant to UK units considering alternatives to more eloquent-tissue-transgressing corridors.

Limitations: Very small, retrospective series with short follow-up and universal early morbidity, so conclusions on safety and reproducibility are tentative and prone to selection bias.

Study Type: Technical note ("How I do it"); descriptive operative technique with no patient cohort, comparator, or outcome data reported in the abstract.

Key Question: Can extraforaminal lumbar disc sequestra be removed effectively through a midline intertransverse approach, rather than a paraspinal or muscle-splitting route?

Key Findings:

• Describes unilateral subperiosteal dissection to expose the isthmus, facet margin, transverse processes and intertransverse ligament.
• Key steps: osteotome removal of the facet margin, resection of the intertransverse ligament, coagulation of the intertransverse artery, then exposure of the nerve root and disc space for sequestrectomy.
• Authors state the approach offers familiar midline anatomy, minimal facet resection and avoidance of muscle splitting. No quantitative outcomes, complication rates or stability data are given in the abstract.

Clinical Relevance: Offers UK spinal surgeons an alternative to Wiltse-type approaches for far lateral herniations, potentially useful where midline orientation is preferred.

Limitations: The abstract presents no clinical outcomes, complication data or comparison with established approaches, so the claimed benefits (effectiveness, preserved stability) remain unsubstantiated.

Study Type: Single-centre retrospective before-and-after cohort study (n = 4,888)

Key Question: Does switching VTE prophylaxis from enoxaparin to tinzaparin alter symptomatic VTE or postoperative rebleeding rates in neurosurgical patients?

Key Findings:

• Low-risk patients: no significant difference in VTE (0.44% vs 0.86%, p = 0.35).
• Moderate-to-high-risk patients: VTE higher with tinzaparin (1.67% vs 0.84%, p = 0.04), driven by PE (1.05% vs 0.18%, p = 0.01); DVT rates similar. Adjusted OR for VTE with enoxaparin 0.475 (95% CI 0.246–0.919).
• Rebleeding requiring evacuation did not differ between agents.

Clinical Relevance: Tinzaparin is widely used in UK practice, so units considering formulary changes should note a possible signal in higher-risk patients, though causality is unproven.

Limitations: The PE excess coincided with increased CTA use and showed no temporal step change at the switch, suggesting detection bias; authors regard findings as hypothesis-generating only.

Study Type: Retrospective prognostic cohort study (prediction model development with external validation), using the Chinese MATCH registry.

Key Question: Can a new multivariable model predict unfavourable neurological outcome (mRS >2) after microsurgical AVM resection better than Spetzler-Martin and Lawton-Young grading?

Key Findings:

• The AVM-NOS includes six predictors: age, AVM volume, eloquence reclassification, deep perforating artery supply, exclusively deep venous drainage, and venous aneurysm.
• Derivation cohort (n=1151): AUC 0.77 (95% CI 0.71-0.83) versus 0.67 for Spetzler-Martin and 0.72 for Lawton-Young.
• External validation (n=75): AUC 0.86 (95% CI 0.77-0.96) versus 0.67 and 0.75 respectively. Calibration and decision-curve analyses were reported as supportive.

Clinical Relevance: If replicated, AVM-NOS could refine surgical selection and counselling beyond current grading systems, though it has not been tested in UK populations or practice.

Limitations: The external validation cohort is small (n=75) with wide confidence intervals that overlap those of Lawton-Young, and the retrospective, single-country design limits generalisability.

Study Type: Retrospective single-centre cohort study (n = 90), with a brief literature review.

Key Question: Does ETV as primary treatment for adult chronic obstructive hydrocephalus improve cognition and gait in the short and longer term?

Key Findings:

• MoCA improved from 23.1 (SD 3.1) to 25.7 at 3 months and 25.8 at 1 year (p < 0.001); the rise met the minimal clinically important difference, and half of patients had normal MoCA scores postoperatively.
• Gait velocity (10-m walk) rose from 1.17 to 1.42 m/sec at 1 year (p < 0.001); the 0.25 m/sec gain was clinically meaningful.
• Improvements appeared by 3 months and were sustained at 1 year.

Clinical Relevance: Provides objective functional outcome data supporting ETV as a first-line option in adult COH, relevant to UK counselling and treatment decisions.

Limitations: Retrospective, uncontrolled design with no comparator (e.g., shunting) and unreported loss to follow-up or etiology-specific outcomes, so selection and practice-effect bias cannot be excluded.

Study Type: Single-centre retrospective cohort study (330 patients, 537 spinal bone metastases; CyberKnife SBRT, 2012–2023).

Key Question: How durable is primary SBRT for spinal metastases, and do ESCC grade, SINS and revised Tokuhashi score predict local control?

Key Findings:

• 1- and 2-year local control 86.2% and 75.9%; median time to local progression 12 months. Independent predictors: radioresistant histology, epidural compression (even minimal; aHR 2.01), osteolytic destruction, pain, dose <20 Gy single-fraction equivalent, and repeat SBRT. SINS 7–12 had worse control than SINS <7 (aHR 1.78).
• An integrated multivariable model outperformed ESCC, SINS and rTS (AUC 0.72–0.75 vs 0.59–0.65). The rTS contribution was largely driven by performance status.
• Acute adverse events 33.9% (pain flare 14.2%); vertebral fracture 17.0%.

Clinical Relevance: Supports SBRT as primary treatment in selected NOMS-eligible patients, and suggests that even low-grade epidural disease or intermediate SINS signals higher failure risk, which is relevant to MDT decisions on separation surgery or dose.

Limitations: Retrospective single-centre design with no external validation of the integrated model; patients with ESCC 2–3 or SINS >12 were excluded, limiting generalisability to surgical-threshold disease.

Study Type: Single-centre retrospective cohort study (2015–2025), n=20.

Key Question: What are the patterns and potential risk factors for mechanical failure after cervical/cervicothoracic junction en bloc spondylectomy with circumferential reconstruction for primary spinal tumours?

Key Findings:

• Instrumentation failure occurred in 3/20 (15%) at 4–44 months: two anterior column events (cage migration, delayed visceral erosion) and one posterior rod fracture.
• Failures were associated with 3.5 mm two-rod constructs, fewer levels fixed above the resection, and cobalt-chromium rods (33% vs 0%, p=0.015); bone density (HU) trended lower in failures.
• 30-day readmission was higher in the failure group (100% vs 17.6%, p=0.004).

Clinical Relevance: For UK sarcoma and spinal oncology centres performing these rare, high-morbidity resections, the findings suggest considering robust proximal fixation and surveillance for late anterior column complications.

Limitations: With only three events, univariate analysis is underpowered and the risk signals are hypothesis-generating rather than confirmatory.

Study Type: Nationwide retrospective registry cohort study (Finland), with propensity score matching.

Key Question: Is preinjury statin use associated with lower mortality and better short-term outcomes after first-admission traumatic brain injury?

Key Findings:

• Among 58,489 TBI patients (18.6% on statins), matched analysis (10,131 pairs) showed lower mortality in statin users: 30-day HR 0.86 (95% CI 0.81–0.92); 1-year HR 0.80 (0.76–0.83).
• Statin users had lower odds of acute neurosurgical operation (7.1% vs 8.1%; OR 0.87, 0.78–0.96) and shorter admission (17.0 vs 19.5 days).
• Lipophilic and high-intensity statins showed greater 1-year survival benefit.

Clinical Relevance: Hypothesis-generating evidence for statins as neuroprotective adjuncts in an ageing UK TBI population, where statin use is common, though not practice-changing.

Limitations: Observational design with residual confounding (e.g., healthy-adherer effect, unmeasured injury severity such as GCS/imaging) means causality cannot be inferred.