Publications by authors named "Natalie Keough"

16 Publications

  • Page 1 of 1

Increased Posterior Slope of the Medial and Lateral Meniscus Posterior Horn Is Associated with Anterior Cruciate Ligament Injuries.

Arthroscopy 2021 May 6. Epub 2021 May 6.

Department of Anatomy, School of Medicine, Faculty of Health Sciences, University of Pretoria, South Africa; Department of Anatomy and Cellular Biology, College of Medicine and Health Sciences, Khalifa University, Abu Dhabi, United Arab Emirates.

Purpose: To measure the slope of the medial and lateral posterior horn of the meniscus and its contribution to the overall resulting posterior tibial slope (bone and meniscus combined slope) in anterior cruciate ligament-intact (ACLI) and -deficient (ACLD) knees.

Methods: Magnetic resonance images of intact menisci in patients 16 to 60 years old were included. Posterior tibial bone slope (PTS) and meniscus slope (MS) were measured 25%, 50%, and 75% from the medial and lateral borders of the tibial plateau. Analysis of variance was used to determine differences in posterior tibial slopes between ACLD and ACLI knees and between sexes for ACLD and ACLI knees.

Results: 192 ACLI patients (age 35.2 ± 9.6 years, mean ± standard deviation) and 159 ACLD patients (age 34.2 ± 10.3 years) were included. Medial and lateral PTS in ACLD was significantly (P = .00001) higher at 25%, 50%, and 75%. Medial and lateral MS in ACLD was significantly (P = .00001) lower at 25%, 50%, and 75%. There were no significant sex differences for medial or lateral MS in ACLD or ACLI patients (P = .51). The resultant combined medial and lateral slope in ACLD patients was significantly (P = .00001) lower at 25%, 50%, and 75%. There were no significant sex differences in PTS (P = .68), MS (P = .51), or resultant slope (P = .79) CONCLUSIONS: The results of this study strongly suggest that lower meniscal slopes of both the medial and lateral posterior horns are associated with ACL injuries in both males and females. Although the posterior horns reversed the bone PTS to an anterior inclined slope in both ACLD and ACLI patients, both the meniscus slope and the combined resultant slope were significantly lower and more positive at all 6 measured locations in ACLD knees.

Level Of Evidence: III, retrospective cohort study.
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http://dx.doi.org/10.1016/j.arthro.2021.04.066DOI Listing
May 2021

Defining the popliteal fossa by bony landmarks and mapping of the courses of the neurovascular structures for application in popliteal fossa surgery.

Anat Cell Biol 2021 Mar;54(1):10-17

Department of Anatomy, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.

Surgical access to the posterior knee poses a high-risk for neurovascular damage. The study aimed to define the popliteal fossa by reliable bony landmarks and comprehensively mapping the neurovascular structures for application in posterior knee surgery. Forty-five (20 male, 25 female) embalmed adult cadaveric knees were included. The position of the small saphenous vein (SSV), medial cutaneous sural nerve (MCSN) and lateral cutaneous sural nerv (LCSN), tibial nerve (TN) and common fibular nerve (CFN) nerves, and popliteal vein (PV) and popliteal artery (PA) were determined in relation to either medial (MFE) or lateral (LFE) femoral epicondyles, medial (MTC) and lateral (LTC) tibial condyles and the midpoint between the MFE and MTC and LFEF and LTC. The distance between the MFE and the PA, PV, TN, MCSN, and SSV was 38.4±12.1 mm, 38.4±12.9 mm, 39.4±10.2 mm, 39.2±14.0 mm and 37.6±12.5 mm respectively for males and 34.6±4.9 mm, 32.8±5.6 mm and 38.0±8.1 mm 38.8±10.1 mm and 37.9±8.2 mm respectively for females. The distance between LFE and the CFN and LCSN was 13.4±8.2 mm and 24.9±7.3 mm respectively for males and 8.4±9.1 mm and 18.4±10.4 mm respectively in females. This study defined the popliteal fossa by reliable bony landmarks and provided a comprehensive map of the neurovascular structures and will help to avoid injuries to the important neurovascular structures.
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http://dx.doi.org/10.5115/acb.20.179DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8017454PMC
March 2021

The posterior horn of the medial and lateral meniscus both reduce the effective posterior tibial slope: a radiographic MRI study.

Surg Radiol Anat 2021 Feb 9. Epub 2021 Feb 9.

Faculty of Health Sciences, Department of Anatomy, School of Medicine, University of Pretoria, Pretoria, South Africa.

Purpose: The purpose of this study was to quantify the posterior horn meniscal slope and determine its contribution to the reduction in posterior tibial slope.

Methods: Patients aged between 16 and 60 years and had intact menisci with no evidence of previous injury or surgery were included. Patients with radiological evidence of osteoarthritis Grade II-IV, any acute or chronic meniscus injuries, fractures, and ligamentous injuries were excluded. The posterior bony slope (PTS) and the meniscus slope (MS) of the posterior horns were measured at 25, 50, and 75% from the medial and lateral borders of the tibial plateau.

Results: 325 MR images (mean age 37.1 ± 10.9 years) were included. There were 194 males and 131 females, with 162 left and 163 right knees. The PTS in the medial compartment ranged from (-) 2.8° to 3.7° and from (-) 1.3° to 1.9° in the lateral compartment (p = 0.0001). The MS in the medial compartment ranged from 27.4° to 28.2°, and from 27.8° to 28.7° in the lateral compartment (p > 0.05). The differences between the medial and lateral knee compartment were statistically significant. At the 25% interval the p level was 0.037, at 50% p = 0.00001, and at 75% p = 0.0001. There were no significant between gender differences.

Conclusions: The results of this study demonstrated a significant reduction in posterior tibial bone slope by the posterior horns of both the medial and lateral meniscus, from a mean of (-) 1° to 2° to a more horizontal anterior slope. The posterior bone slope was larger in the medial compartment by 1°, resulting in a smaller slope reduction in the lateral compartment.
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http://dx.doi.org/10.1007/s00276-021-02696-8DOI Listing
February 2021

A quantitative analysis of the dimensions and content of the vertebral triangle.

Surg Radiol Anat 2021 Jun 2;43(6):881-888. Epub 2021 Feb 2.

Department of Anatomy, Faculty of Health Science, School of Medicine, University of Pretoria, Pretoria, South Africa.

Purpose: The vertebral triangle (VT) located in the root of the neck most commonly contains the vertebral artery (VA), cervical sympathetic chain and certain roots of the brachial plexus. Although other structures have been reported, few studies have reported on the overall content of this space. Based on the current literature, there is a general paucity of anatomical information pertaining to the dimensional anatomy of the VT and specifically the structures related to it. Therefore, this study aimed to quantitatively analyze the size, position, content, and anatomical structures in relation to the vertebral triangle in a South African sample.

Methods: Forty-three VTs were dissected on bodies donated to science. Measurements taken include the dimensions of the triangle, as well as distances between prominent structures and landmarks of the VT. Observations were made on the presence/absence of the varying neurovascular structures within the VT.

Results: Mean height was 30.1 ± 1.51 mm (R) and 32.9 ± 1.78 mm (L). Mean width was 18.3 ± 0.74 mm (R) and 19.3 ± 0.98 mm (L). The C8 spinal nerve was found on average approximately halfway [16.4 ± 0.74 mm (R) and 15.9 ± 0.95 mm (L)] in the VT. The VA was present in the VT in 100% of the sample and the C7 spinal nerve and inferior sympathetic ganglia were present in more than 80% of the sample.

Conclusion: Understanding the VT and the content is of the utmost importance and of great interest to neurosurgeons, to avoid these important neurovascular structures and prevent iatrogenic complications during surgery.
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http://dx.doi.org/10.1007/s00276-020-02645-xDOI Listing
June 2021

The anatomical relationship of the common peroneal nerve to the proximal fibula and its clinical significance when performing fibular-based posterolateral reconstructions.

Arch Orthop Trauma Surg 2021 Mar 3;141(3):437-445. Epub 2021 Jan 3.

Department of Anatomy, Faculty of Health Sciences, School of Medicine, University of Pretoria, Pretoria, South Africa.

Purpose: The common peroneal nerve (CPN) can be injured during fibular-based posterolateral reconstructions due to its close relationship to the neck of the fibula. Therefore, the purpose of this study was to observe the course of the CPN and its branches around the fibular head and neck and quantify the position in relation to relevant bony landmarks and observe the relation between tunnel drilling for posterolateral corner reconstruction and both the tunnel entry and exit at the proximal fibula and the CPN and its branches was observed.

Methods: In 101 (mean age = 70.6 ± 16 years) embalmed cadaver knees, the relationship between bony landmarks (tibial tuberosity, styloid process of fibula (APR)) and the CPN and its branches were established and 8 (M1-M8) distances from these landmarks measured; mean, SD and 95% CI were recorded. In 21 of these knees, a fibula tunnel was drilled as in PLC reconstruction and the association of the CPN and its branches to the tunnel entry and exit were judged by two independent observers. Fisher's exact test of independence was used to determine significant differences between genders. Tunnel intersection was analysed in a binary yes/no fashion and was described in frequencies and percentages.

Results: The mean distance from the APR to where the CPN reaches the fibula neck (M1) was 31.4 ± 8.9 mm (CI:29.8-33.0); from the apex of the styloid process (APR) to where the CPN passes posterior to the broadest point of the fibular head (M3) was 21.7 ± 12.6 mm (CI:19.4-24.0); from the apex of the APR to the most proximal point of the CPN/CPN first branch in the midline of the fibular head (M2) was 37.0 ± 6.7 mm (CI: 35.4-37.7). Out of the 21 randomly selected knees for drilling, the first branch of the CPN was damaged at the tunnel entry point in 7 (33%), and in 5 knees (24%), the CPN was damaged at the tunnel exit. In one knee, at both the tunnel entry and exit, the first branch of the CPN and the CPN were intersected, respectively.

Conclusion: The results of this study strongly suggest that the CPN is at risk when drilling the fibula tunnel performing fibula-based posterolateral corner reconstructions. The total injury rate was 57% with a 33% incidence of injury to the first branch of the nerve at the tunnel entry and 24% to the CPN at the tunnel exit.

Clinical Relevance: Due to the high incidence of injury, percutaneous placement of guide pins and tunnel drilling is not recommended. The nerve should be visualized and protected by either a traditional open approach or minimally invasive techniques. With a minimally invasive approach, the nerve should be identified at the fibula neck and then followed ante- and retrograde.
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http://dx.doi.org/10.1007/s00402-020-03708-9DOI Listing
March 2021

The determination of safe zones for arthroscopic portal placement into the posterior knee by mapping the courses of neurovascular structures in relation to bony landmarks.

Eur J Orthop Surg Traumatol 2021 Jan 3. Epub 2021 Jan 3.

Valiant Clinic/Houston Methodist Group, Dubai, United Arab Emirates.

Purpose: Minimally invasive surgery in the posterior knee is high risk for iatrogenic injury to popliteal neurovascular neurovasculature structures. This study aimed to use reliable landmarks to define safe zones for arthroscopic portal placement into the posterior knee.

Methods: Distances were measured between bony landmarks and neurovascular structures within the popliteal fossa using 45 formalin-embalmed cadavers: small saphenous vein (SSV), medial (MCSN) and lateral (LCSN) cutaneous sural nerves, tibial nerve (TN), common fibular nerve (CFN), popliteal vein (PV) and artery (PA). The structures were measured in relation to medial (MEF) and lateral (LEF) femoral epicondyle, medial (MCT) and lateral (LCT) tibial condyle and the midpoint between the landmarks.

Results: The mean distance (mm) between MEF and structures was, male and female, respectively: SSV 37.6 + 12.5, 37.9 + 8.2; MCSN 39.2 + 14, 38.8 + 10.1; TN 39.4 + 10.2, 38.0 + 8.1; PV 38.4 + 12.9, 32.8 + 5.6; PA 38.4 + 12.1, 34.6 + 4.9. At midpoint and MCT all structures medialized between 5 and 28%. The mean distance between LEF and structures was, male and female, respectively: CFN 13.4 + 8.2, 8.4 + 9.1; LCSN 24.9 + 7.3, 18.4 + 10.4. At midpoint and LCT the CFN lateralized by 37-42% and the LCSN medialized by 8-9%.

Conclusions: Results suggest posteromedial portal placement can be safely established < 20 mm from the medial femoral epicondyle, tibial condyle or the midpoint between the two landmarks. Posterolateral portal placement is of higher risk, and entry point is 18 mm from the lateral femoral epicondyle, tibial condyle or the midpoint between the two landmarks in males and 12 mm in females. These landmarks will allow safe portal placement in 99% of cases.
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http://dx.doi.org/10.1007/s00590-020-02847-4DOI Listing
January 2021

The position of the common facial vein in neonates: An alternate route for central venous catheter placement.

Clin Anat 2021 May 9;34(4):644-650. Epub 2020 Oct 9.

Department of Anatomy, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.

Introduction: We determine the location of the common facial vein (CFV) in a sample of neonates and assess the safety of this vein as an alternative access route for a central venous catheter (CVC).

Materials And Methods: We dissected both the left and right sides of the neck region in 24 neonatal, formalin-fixed cadavers, exposing the underlying soft tissues and neurovascular structures. We identified the CFV, which we then pinned together with the internal jugular vein, cervical branch of facial nerve, marginal mandibular branch of the facial nerve, the cricoid cartilage, brachiocephalic vein, and the mastoid and sternal attachments of the sternocleidomastoid muscle. We measured the CFV and the related pinned structures.

Results: In neonates, the CFV intersected the anterior border of sternocleidomastoid on average 19.53 mm (left) and 21.73 mm (right) from its sternal attachment.

Conclusion: We found the CFV inferior to the upper one third and just superior to half of the length of the sternocleidomastoid muscle, indicating a possible "safe-zone" where a skin incision could be made over the anteromedial border of sternocleidomastoid. The CFV is easily identified from surrounding landmarks. It could be used as a safe, alternative route for inserting a CVC if its average length (8.72 mm) and diameter (1.50 mm) are taken into account.
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http://dx.doi.org/10.1002/ca.23685DOI Listing
May 2021

Kambin's triangle and the position of the dorsal nerve root in the lumbar neural foramen.

Clin Anat 2020 Nov 21;33(8):1204-1213. Epub 2020 Jan 21.

Department of Anatomy, University of Pretoria, Pretoria, Gauteng, South Africa.

Introduction: As a result of the increased utilization of neurosurgical arthroscopic techniques, investigations into population and sex-specific trends of anatomical considerations have become increasingly important. This study aimed to investigate and describe aspects of the neuroanatomical morphometry of lumbar spines in a cadaveric and magnetic resonance imaging (MRI) sample.

Materials And Methods: Twenty white adult (>18 years) cadavers (9 males; 11 females) were obtained under Ethical clearance. The lumbar regions were dissected and the position of the dorsal root ganglion (DRG) and dimensions of Kambin's triangle were determined. Twenty-six black adult (>18 years) MRI scans (17 males; 9 females) were obtained from an Academic Hospital and were used to determine the dimensions of the neural foramen and the DRGs within.

Results: The ganglia were mostly at the midline of the caudal pedicle. Similar to previous studies, the diagonal measurement from Kambin's triangle was the largest and the vertical measurement the shortest. Skeletal and soft-tissue measurements indicated distinct trends when moving caudolaterally in the spine. Soft-tissue parameters from the current study were within the upper limits of those from previous studies, whereas skeletal parameters were in agreement with those reported by previous authors.

Conclusions: Results from this study suggest a variation of certain parameters between studies with varying population groups and therefore supports the need for and the importance of possible population-specific trends of anatomical parameters considered during surgical procedures.
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http://dx.doi.org/10.1002/ca.23565DOI Listing
November 2020

An anatomical investigation into the blood supply of the proximal humerus: surgical considerations for rotator cuff repair.

JSES Open Access 2019 Dec 18;3(4):320-327. Epub 2019 Nov 18.

Department of Orthopaedic Surgery and Sports Medicine, Valiant Clinic/Houston Methodist Group, Dubai, United Arab Emirates.

Background: The purpose of this study was to investigate the blood supply of the humeral head (HH) originating from the anterior (ACHA) and posterior circumflex humeral arteries (PCHA).

Methods: Formalin preserved specimens were used to measure ACHA length, ACHA length in the bicipital groove (BG), the length of the ascending branch of the ACHA, the penetration point of the ascending branch of the ACHA at the greater tuberosity (GT), and the penetration point of the ascending branch PCHA at the GT. Fresh specimens were used to identify the intraosseous vascular network by both the ACHA and PCHA by injecting a contrast medium using a high-resolution microfocus computed tomography. Specimens were then dissected to expose where the branches of the ACHA and PCHA penetrate the bone, and a small section of the medial head was removed to visualize dye penetration of the cancellous bone.

Results: Seven variations for the course of the ACHA were observed. In 36%, the ACHA runs posterior to the BG and posterior to the long head of biceps tendon, and splits into the anterolateral ascending and descending branch. The ascending branch enters the medial wall of the GT. Microfocus computed tomography demonstrated that the intraosseous branch of the ascending branch of the ACHA runs within the GT in a medial direction from its penetration point just along the lateral edge of the BG. Intraosseous accumulation of contrast within the GT supply occurs more toward the inferior aspect of the HH, and the anterior-superior and superior-medial aspect of the HH is not perfused. This region is a high-risk zone for avascular necrosis.

Conclusion: The results of this study suggest that 7 variations for the course of the ACHA exist. These variations and the interruption of the intraosseous arterial network in the GT with surgery and suture anchor placement result in a high-risk zone in the superomedial aspect of the humeral head overlapping with the area where early aseptic necrosis is identified.
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http://dx.doi.org/10.1016/j.jses.2019.09.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6928301PMC
December 2019

Defining the anatomy of the neonatal lingual frenulum.

Clin Anat 2019 Sep 3;32(6):824-835. Epub 2019 Jun 3.

Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.

The lingual frenulum is recognized as having the potential to limit tongue mobility, which may lead to difficulties with breastfeeding in some infants. There is extensive variation between individuals in the appearance of the lingual frenulum but an ambiguous relationship between frenulum appearance and functional limitation. An increasing number of infants are being diagnosed with ankyloglossia, with growing uncertainty regarding what can be considered "normal" lingual frenulum anatomy. In this study, microdissection of four fresh tissue premature infant cadavers shows that the lingual frenulum is a dynamic, layered structure formed by oral mucosa and the underlying floor of mouth fascia, which is mobilized into a midline fold with tongue elevation and/or retraction. Genioglossus is suspended from the floor of mouth fascia, and in some individuals can be drawn up into the fold of the frenulum. Branches of the lingual nerve are located superficially on the ventral surface of the tongue, immediately beneath the fascia, making them vulnerable to injury during frenotomy procedures. This research challenges the longstanding belief that the lingual frenulum is a midline structure formed by a submucosal "band" or "string" and confirms that the neonatal lingual frenulum structure replicates that recently described in the adult. This article provides an anatomical construct for understanding and describing variability in lingual frenulum morphology and lays the foundation for future research to assess the impact of specific anatomic variants of lingual frenulum morphology on tongue mobility. Clin. Anat. 32:824-835, 2019. © 2019 The Authors. Clinical Anatomy published by Wiley Periodicals, Inc. on behalf of American Association of Clinical Anatomists.
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http://dx.doi.org/10.1002/ca.23410DOI Listing
September 2019

Apprasial of the surface anatomy of the Thorax in an adolescent population.

Clin Anat 2019 Sep 3;32(6):762-769. Epub 2019 Mar 3.

Department of Anatomy, Faculty of Health Sciences, School of Medicine, University of Pretoria, Pretoria, South Africa.

Surface anatomy is considered a fundamental part of anatomy curricula and clinical practice. Recent studies have reappraised surface anatomy using CT, but the adolescent age group has yet to be appraised. Sixty adolescent thoracoabdominal CT scans (aged 12-18 years) were examined. The surface anatomy of the central veins, cardiac apex, diaphragmatic openings, and structures in relation to the sternal angle plane were analyzed. The results showed that the brachiocephalic vein (left and right) formed mostly posterior to the sternoclavicular joint. The superior vena cava formed close to the second costal cartilage, ±16.3 mm to the right of the midline. The apex of the heart was located in relation to the fifth intercostal space; ±78.6 mm to the left of the midline. The caval hiatus was in relation to T9 and T10; the esophageal hiatus was at T10; whereas the aortic hiatus was at T11. The sternal angle plane was in relation to the upper half of T5, which was also where the bifurcations of the trachea and pulmonary trunk were observed. The SVC/azygos vein junction and the concavity of the aortic arch were observed to be more than 10 mm superior to this plane. The results of this study further highlight the substantial variability of the surface anatomy between age groups. It also emphasizes the notion that surface anatomy is a dynamic variable and cannot be treated as a static observation. Clin. Anat. 32:762-769, 2019. © 2019 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/ca.23351DOI Listing
September 2019

Inter- and intraclass correlations for three standard foot radiographic measurements for plantar surface angles. Which measure is most reliable?

Foot Ankle Surg 2019 Oct 26;25(5):646-653. Epub 2018 Jul 26.

Department of Orthopaedic Surgery, University of Texas Health Science Center, San Antonio, TX, USA.

Background: The purpose of this study was to evaluate the reliability and reproducibility of three commonly used radiographic measures for plantar surface angles.

Methods: The calcaneal angle (CA), calcaneal pitch angle (CPA), and length-height index (LHI) was measured by three independent examiners on two occasions on lateral foot radiographs. Intra- and inter-rater correlations were calculated using a general linear estimate model and post-hoc tests for repeated measures. Bland-Altman's plots with limits of agreement were used for observer differences in scores.

Results: The intra-class correlations for the CA ranged from 0.91 to 0.94, for the CPA from 0.93 to 0.98, and for the LHI from 0.96 to 0.97. The inter-class correlations were 0.80 for CA, 0.83 for CPA and 0.93 for LHI.

Conclusions: The results of this study strongly suggest that the length-height index was the most consistent and reliable measure for arch height.

Level Of Evidence: Diagnostic Level II, validity.
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http://dx.doi.org/10.1016/j.fas.2018.07.007DOI Listing
October 2019

The mechanical properties of fresh versus fresh/frozen and preserved (Thiel and Formalin) long head of biceps tendons: A cadaveric investigation.

Ann Anat 2019 Jan 4;221:186-191. Epub 2018 Jun 4.

Department of Orthopaedic Sports Medicine, Technical University of Munich, Germany.

Human cadaveric specimens commonly serve as mechanical models and as biological tissue donors in basic biomechanical research. Although these models are used to explain both in vitro and in vivo behavior, the question still remains whether the specimens employed reflect the normal in vivo situation. The mechanical properties of fresh-frozen or preserved cadavers may differ, and whether they can be used to reliably investigate pathology could be debated. The purpose of this study was to therefore examine the mechanical properties of cadaveric long biceps tendons, comparing fresh (n=7) with fresh-frozen (n=8), formalin embalmed (n=15), and Thiel-preserved (n=6) specimens using a Universal Testing Machine. The modulus of elasticity and the ultimate tensile strength to failure was recorded. Tensile failure occurred at an average of 12N/mm in the fresh group, increasing to 40.1N/mm in the fresh-frozen group, 50.3N/mm in the formalin group, and 52N/mm in the Thiel group. The modulus of elasticity/stiffness of the tendon increased from fresh (25.6MPa), to fresh-frozen (55.3MPa), to Thiel (82.5MPa), with the stiffest being formalin (510.6MPa). Thiel-preserved and formalin-embalmed long head of biceps tendons and fresh-frozen tendons have a similar load to failure. Either the Thiel or formalin preserved tendon could therefore be considered as alternatives for load to failure studies. However, the Young's modulus of embalmed tendons were significantly stiffer than fresh or fresh frozen specimens, and these methods might be less suitable alternatives when viscoelastic properties are being investigated.
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http://dx.doi.org/10.1016/j.aanat.2018.05.002DOI Listing
January 2019

Single- versus double-row repair for full-thickness rotator cuff tears using suture anchors. A systematic review and meta-analysis of basic biomechanical studies.

Eur J Orthop Surg Traumatol 2018 Jul 21;28(5):859-868. Epub 2017 Dec 21.

Department of Anatomy, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.

Purpose: The purpose of this study was to perform a systematic review and meta-analysis comparing single- and double-row biomechanical studies to evaluate load to failure, mode of failure and gap formation.

Materials And Methods: A systematic review of MEDLINE, Embase, Scopus and Google Scholar was performed from 1990 through 2016. The inclusion criteria were: documentation of ultimate load to failure, failure modes and documentation of elongation or gap formation. Studies were excluded if the study protocol did not use human specimens. Publication bias was assessed by funnel plot and Egger's test. The risk of bias was established using the Cochrane Collaboration's risk of bias tool. Heterogeneity was assessed using χ and I statistic.

Results: Eight studies were included. The funnel plot was asymmetric suggesting publication bias, which was confirmed by Egger's test (p = 0.04). The pooled estimate for load to failure demonstrated significant differences (SMD 1.228, 95% CI: 0.55-5.226, p = 0.006, I  = 60.47%), favouring double-row repair. There were no differences for failure modes. The pooled estimate for elongation/gap formation demonstrated significant differences (SMD 0.783, 95% CI: 0.169-1.398, p = 0.012, I  = 58.8%), favouring double-row repair.

Conclusion: The results of this systematic review and meta-analysis suggest that double-row repair is able to tolerate a significantly greater load to failure. Gap formation was also significantly lower in the double-row repair group, but both of these findings should be interpreted with caution because of the inherent interstudy heterogeneity.

Level Of Evidence: Systematic review and meta-analysis.
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http://dx.doi.org/10.1007/s00590-017-2114-6DOI Listing
July 2018

Scoring of Decomposition: A Proposed Amendment to the Method When Using a Pig Model for Human Studies.

J Forensic Sci 2017 Jul 29;62(4):986-993. Epub 2016 Dec 29.

Human Variation and Identification Research Unit, Faculty of Health Sciences, School of Anatomical Sciences, University of the Witwatersrand, 7 York Road, Parktown, 2193, South Africa.

Decomposition studies often use pigs as proxies for human cadavers. However, differences in decomposition sequences/rates relative to humans have not been scientifically examined. Descriptions of five main decomposition stages (humans) were developed and refined by Galloway and later by Megyesi. However, whether these changes/processes are alike in pigs is unclear. Any differences can have significant effects when pig models are used for human PMI estimation. This study compared human decomposition models to the changes observed in pigs. Twenty pigs (50-90 kg) were decomposed over five months and decompositional features recorded. Total body scores (TBS) were calculated. Significant differences were observed during early decomposition between pigs and humans. An amended scoring system to be used in future studies was developed. Standards for PMI estimation derived from porcine models may not directly apply to humans and may need adjustment. Porcine models, however, remain valuable to study variables influencing decomposition.
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http://dx.doi.org/10.1111/1556-4029.13390DOI Listing
July 2017

Application of FORDISC 3.0 to explore differences among crania of North American and South African blacks and whites.

J Forensic Sci 2013 Nov 18;58(6):1579-83. Epub 2013 Jul 18.

Department of Anatomy, University of Pretoria, Private Bag x323, 0007, Arcadia, South Africa.

Using discriminant function analysis, classification accuracies for ancestry and sex in white and black South Africans were compared using North American (FDB), African groups in Howells (HDB), and South African (SADB) databases in FORDISC 3.0. (FD3). Twenty-four standard linear measures were collected from a total of 86 black and 101 white crania obtained from the Pretoria Bone Collection. White and black South Africans classified 73% correctly in FDB, 55% correctly in HDB, and 71% correctly in SADB. The percentage of atypical cases was higher with FDB than SADB. In all three databases, misclassification occurred more with sex than ancestry revealing differences in sexual dimorphism between population groups. Broad ancestral differences may explain low misclassification rates for ancestry. FD3, with a modern South African reference sample, can assist South African anthropologists to standardize methodology and to justify procedures for estimating ancestry.
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http://dx.doi.org/10.1111/1556-4029.12198DOI Listing
November 2013