Jakub R. Pękala

Prevalence of foramen arcuale and its clinical significance: a meta-analysis of 55,985 subjects

OBJECTIVE The foramen arcuale (FA) is a bony bridge located over the vertebral artery on the posterior arch of the atlas. The presence of an FA can pose a risk during neurosurgery by providing a false impression of a broader posterior arch. The aim of this study was to provide the most comprehensive investigation on the prevalence of the FA and its clinically important anatomical features. METHODS Major electronic databases were searched to identify all studies that reported relevant data on the FA and the data were pooled into a meta-analysis. RESULTS A total of 127 studies (involving 55,985 subjects) were included. The overall pooled prevalence of a complete FA was 9.1% (95% CI 8.2%-10.1%) versus an incomplete FA, which was 13.6% (95% CI 11.2%-16.2%). The complete FA was found to be most prevalent in North Americans (11.3%) and Europeans (11.2%), and least prevalent among Asians (7.5%). In males (10.4%) the complete FA was more common than in females (7.3%) but an incomplete FA was more commonly seen in females (18.5%) than in males (16.7%). In the presence of a complete FA, a contralateral FA (complete or incomplete) was found in 53.1% of cases. CONCLUSIONS Surgeons should consider the risk for the presence of an FA prior to procedures on the atlas in each patient according to sex and ethnic group. We suggest preoperative screening with computerized tomography as the gold standard for detecting the presence of an FA.

Oblique incisions in hamstring tendon harvesting reduce iatrogenic injuries to the infrapatellar branch of the saphenous nerve

PurposeIatrogenic injury to the infrapatellar branch of the saphenous nerve (IPBSN) is associated with many surgical interventions to the medial aspect of the knee, such as anterior cruciate ligament (ACL) reconstruction. Different types of surgical incisions during hamstring tendon harvesting for ACL reconstruction are related to a variable risk of IPBSN injury. This study aimed to evaluate the risk of iatrogenic IPBSN injury during hamstring tendon harvesting for ACL reconstruction with different incision techniques over the pes anserinus.MethodsThis study was performed on 100 cadavers. Vertical, horizontal, or oblique incisions were simulated on each cadaveric limb to determine the incidence of iatrogenic IPBSN injury.ResultsThe vertical incision caused the IPBSN injury during hamstring tendon harvesting in 101 (64.7%), the horizontal incision in 78 (50.0%), and the oblique incision in 43 (27.6%) examined lower limbs. The calculated odds ratios (OR) for risk of injury in vertical versus horizontal and horizontal versus oblique incisions were 2.4 (95% CI 1.5–3.6) and 1.8 (95% 1.2–2.8), respectively.ConclusionsThe vertical incision technique over the pes anserinus should be avoided during hamstring tendon harvesting for ACL reconstruction. The adoption of an oblique incision, with the shortest possible length, will allow for the safest procedure possible, thus minimizing the risk of iatrogenic IPBSN injury, and improving patient outcomes and postoperative quality-of-life.

Lateral and posterolateral foraminal variations of the atlas: A meta-analysis

The lateral (LF) and posterolateral (PLF) foramina are anatomical variants of the atlas. Both variants have been implicated in multiple neurological conditions including vertebrobasilar insufficiency, with symptoms such as dizziness, syncope, auditory and visual disturbances and paresis. The aim of this study was to conduct a systematic meta-analysis on the prevalence and anatomical characteristics of the LF and PLF. An extensive search of the major electronic databases was conducted to identify all studies that reported relevant data on the LF and PLF. No date or language restrictions were applied. Data on the prevalence, type (complete and incomplete), side, gender, and laterality of the LF and PLF, when available, were extracted and pooled into a meta-analysis. A total of 33 studies (n=10,190 subjects) were included in the quantitative analysis. The overall pooled prevalences of complete LF and PLF were 2.6% (95%CI: 2.1-3.1) and 1.2% (95%CI:0.6-2.0), respectively, while the overall pooled prevalence of the incomplete LF was 2.7% (95%CI:1.3-4.4) and the incomplete PLF was 0.7% (95%CI:0.0-1.8). When there was a complete PLF, a contralateral PLF (complete or incomplete) was found in 32.8% of cases. The geographical distribution of both variants was variable. The findings of this study provide an evidence-based foundation of anatomical knowledge of the two variants of the atlas. We recommend that physicians consider the possible role of the LF and PLF during the diagnosis of various neurological disturbances, especially in situations when all other possible explanations for the symptoms have been excluded.

The Achilles tendon and the retrocalcaneal bursa: An anatomical and radiological study

Objectives Inflammation of the retrocalcaneal bursa (RB) is a common clinical problem, particularly in professional athletes. RB inflammation is often treated with corticosteroid injections however a number of reports suggest an increased risk of Achilles tendon (AT) rupture. The aim of this cadaveric study was to describe the anatomical connections of the RB and to investigate whether it is possible for fluid to move from the RB into AT tissue. Methods A total of 20 fresh-frozen AT specimens were used. In ten specimens, ink was injected into the RB. The remaining ten specimens were split into two groups to be injected with radiological contrast medium into the RB either with or without ultrasonography guidance (USG). Results In specimens injected with ink, diffusion outside the RB was observed with staining of the anterior portion of the AT. In eight contrast-injected specimens (five USG, three non-USG), a similar localised diffusion pattern was observed, with the contrast identified superiorly and anteriorly. In two contrast-injected specimens (non-USG), the diffusion pattern was more extensive. Conclusion This study confirmed the existence of connections between the RB and the AT, especially rich in the anteroinferior portion of the tendon, which should be considered a weak zone for substances injected into the RB. We hypothesise that this part of the AT might be most vulnerable to rupture after corticosteroid injections. Cite this article: P. A. Pękala, B. M. Henry, J. R. Pękala, K. Piska, K. A. Tomaszewski. The Achilles tendon and the retrocalcaneal bursa: An anatomical and radiological study. Bone Joint Res 2017;6:446–451. DOI:10.1302/2046-3758.67.BJR-2016-0340.R1.

Presence of a foramen arcuale as a possible cause for headaches and migraine: Systematic review and meta-analysis

The foramen arcuale (FA) is an osseous bridge that can be formed on the posterior arch of the atlas, often observed on lateral radiographs of the cervical spine. Currently, there is a lack of studies that systematically review the available literature on the FA and its role in headaches and migraines. Therefore, we conducted an extensive search of the major electronic databases to identify all studies that reported relevant data on patients with versus without FA and prevalence of headaches or migraines. No date or language restrictions were applied. Data on the prevalence, type (complete and incomplete), and laterality of the FA and relationship with headaches or migraines were extracted and pooled into a meta-analysis. There were 168/412 (40.8%) patients with headaches in the FA group compared to 368/1691 (21.8%) patients with headaches in the no FA group (OR 4.68; P = 0.002). The proportion of headaches for complete FA was 73/125 (58.4%) compared with 80/413 (19.4%) for incomplete FA (OR 5.04; P = 0.04). When comparing incomplete FA to no FA, the proportion of headaches was 36/85 (42.3%) vs 65/560 (11.6%), and this was significantly different (OR 6.13; P = 0.009). The proportion of headaches in patients with bilateral FA was 67/132 (50.8%) compared to 80/140 (57.1%) in the unilateral group (OR 1.36; P = 0.72). We performed the first meta-analysis to demonstrate the significant association between FA and headaches, and provided further support for the notion of the clinical relevance of this anatomical variant.

Internal and external morphology of mandibular molars: An original micro-CT study and meta-analysis with review of implications for endodontic therapy: Morphology of Mandibular Molars

The aim of this radiological micro‐CT study and meta‐analysis was to determine the morphological features of the root canal anatomy of the mandibular molars. The radiological study included micro‐CT scans of 108 mandibular first, 120 mandibular second, and 146 mandibular third molars. For our meta‐analysis, an extensive search was conducted through PubMed, Embase, and Web of Science to identify articles eligible for inclusion. Data extracted included investigative method (cadaveric, intraoperative, or imaging), Vertucci type of canal configuration, presence/number of canals, roots, apical foramina, apical deltas, and intercanal communications. In the mesial roots of mandibular molars, the most frequent Vertucci type of canal configuration was type IV, except for the mandibular third molar where type I was most common. Type I was most common in the distal root. There were usually two canals in the mesial root and one in the distal root. Two was the most common number of roots, and a third root was most prevalent in Asia. One apical foramen was most common in the distal root and two apical foramina in the mesial root. Intercanal communications were most frequent in the mesial root. Knowledge of the complex anatomy of the mandibular molars can make root canal therapy more likely to succeed. We recommend the use of cone‐beam computed tomography before and after endodontic treatment to enable the root anatomy to be accurately described and properly diagnosed, and treatment outcome to be assessed. Clin. Anat. 31:797–811, 2018.

Prevalence of the petrosquamosal sinus and its clinical significance: a radiological study and meta-analysis

OBJECTIVE The petrosquamosal sinus (PSS) is clinically important as it represents a potential hemorrhagic hazard during neurosurgical procedures. This double-approach radiologic study and meta-analysis aimed to assess the imaging characteristics of the PSS on computed tomography (CT) and systematically analyze its prevalence to improve imaging accuracy and assist in neurosurgical management. METHODS The retrospective radiologic study included CT scans of 388 patients aged 18 years or older. All patients with any visible intracranial pathologies or history of head trauma were excluded. To identify articles eligible for inclusion in our meta-analysis, an extensive search was conducted through PubMed, Embase, ScienceDirect, Web of Science, and CNKI. Data extracted included investigative method, prevalence of the PSS among subjects, ethnicity, gender, side, laterality, and mean diameter. The extracted data were pooled into a meta-analysis with a random-effects model. RESULTS The radiologic study showed that the PSS was visualized in 25.5% of the sides examined, that it was slightly more common among females (27.5%) than males (23.8%) and on the left (21.7%) than the right (29.4%). Its mean diameter was 1.14 ± 0.58 mm. The meta-analysis revealed that the overall prevalence of the PSS in the population is 11.1%, that it is more common in females (27.4%) than males (17.6%), and that a unilateral PSS is more common (78.2%) than a bilateral one (21.8%). CONCLUSIONS As a PSS is present in about one tenth of the population, it is important to consider the possibility that it is present when undertaking neurosurgical procedures and to assess preoperative CT scans to avoid complications.

Congenital absence of the palmaris longus muscle: A meta-analysis comparing cadaveric and functional studies

The aim of our paper was to provide comprehensive data on the prevalence of absence of palmaris longus muscle (PLM) and its anatomical characteristics and conduct two separate meta-analyses comparing cadaveric and functional studies while identifying variation among different ethnic groups. An extensive search was conducted through the major electronic databases to identify eligible articles. Data extracted included prevalence of absence of PLM among subjects, ethnicity, laterality, side, and gender. Our main findings revealed that the absence of PLM is more frequently reported in functional studies. Moreover, functional tests likely overestimated the absence of PLM and recommend future studies to assess the validity of functional tests and use an imaging assessment prior to excluding the use of a palmaris longus tendon graft in patients in whom a function test identified the absence of PLM.

The prevalence and morphology of the corona mortis (Crown of death): A meta-analysis with implications in abdominal wall and pelvic surgery

PURPOSE Corona mortis is a highly variable vascular connection between the obturator and external iliac or inferior epigastric arteries or veins located behind the superior pubic ramus in the retropubic space (space of Retzius). Due to the significant variation in this collateral circulation, detailed anatomical knowledge of the corona mortis is vital to enhance the prevention of possible iatrogenic errors in hernia repair and other pubic surgical procedures. The aim of our meta-analysis was to provide comprehensive data on the prevalence, anatomical characteristics, and ethnic variations of the corona mortis vessel. METHODS An extensive search was conducted through the major electronic databases to identify eligible articles. Data extracted included investigative method, prevalence of the corona mortis vessels among hemi-pelvises (overall, arterial only, venous only, and combined), distance from the corona mortis to pubic symphysis, and assessment of gender, side, laterality, and ethnicity subgroups. RESULTS A total of 21 studies (n=2184 hemi-pelvises) were included in the meta-analysis. The overall prevalence of the corona mortis in hemi-pelvises is high (49.3%). A venous corona mortis is more prevalent than an arterial corona mortis (41.7% vs. 17.0%). The corona mortis is more common in Asia (59.3%) than in Europe (42.8%) and North America (44.3%). CONCLUSIONS As a corona mortis is present in an about half of all hemi-pelvises, it is important to consider the possibilities of its presence when undertaking surgical procedures and plan accordingly to avoid injuries. All surgeons operating in the retropubic region should have a thorough understanding of the anatomical characteristics and surgical implications of a corona mortis.