Avulsion Fractures of the Transverse Processes of the First Thoracic Vertebra: An Archaeological Case Study from Raunds

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1 International Journal of Osteoarchaeology Int. J. Osteoarchaeol. 19: (2009) Published online 23 July 2008 in Wiley InterScience ( SHORT REPORT Avulsion Fractures of the Transverse Processes of the First Thoracic Vertebra: An Archaeological Case Study from Raunds B. R. UPEX* y AND C. J. KNÜSEL Biological Anthropology Research Centre (BARC), Archaeological Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, BD71DP, UK ABSTRACT Avulsion fractures of the transverse processes of vertebrae have not been previously identified in the archaeological record. This paper provides a case study of a year old male skeleton from the 10 th century cemetery at Raunds Furnells (Northamptonshire, UK) with bilateral avulsion fractures of the transverse processes of the first thoracic vertebra. Possible aetiologies of this condition are discussed and conclusions drawn about the impact of this condition upon the individual. Copyright ß 2008 John Wiley & Sons, Ltd. Key words: vertebral avulsion; transverse processes; Raunds (Northants; UK); trauma; 10 th century Introduction The Anglo-Saxon cemetery of Raunds Furnells is located on the south side of the Nene Valley in East Northamptonshire, UK. The earliest settlement on the site was established in the 6 th century AD, and the site was continuously occupied until the 15 th century. By the early 10 th century the first church was built on the site, and burials commenced shortly after, close to the church walls and then expanded to the south and * Correspondence to: Biological Anthropology Research Centre (BARC), Archaeological Sciences, School of Life Sciences, University of Bradford, Bradford, West Yorkshire, BD71DP, UK. beth_up@yahoo.com y Current Address: Department of Archaeology, Durham University, South Road, Durham, DH1 3LE, UK. east of the site. The majority of the graves appear to be associated with the first phase of church building dating to the mid-10 th century (Boddington, 1996). The site was extensively excavated between 1977 and 1984 in response to a development project that threatened its destruction. The excavations covered the entire area of the church as well as the cemetery, which contained a total of 363 burials (Boddington, 1996). Skeleton 5046 Skeleton 5046 was located at the very end of row 22 in zone 5 (see Table 1), adjacent to the boundary of the churchyard (see Figure 1). Copyright # 2008 John Wiley & Sons, Ltd. Received 28 November 2006 Revised 15 October 2007 Accepted 21 November 2007

2 Vertebral Avulsions 117 Table 1. Data relating to Zone 5 (modified from Boddington, 1996) Information % in zone 5 Parallel burial 34.5% Non-parallel burial 65.5% With stone arrangements in the grave 67% Without stone arrangements in the grave 32% Males 82.1% Females 17.9% Adults 53.3% Adolescents, children & infants 46.7% A detailed assessment of this individual revealed that the remains were of a well-preserved and relatively complete adult male, aged between 21 and 25, who stood at around cm tall for this population where the average male height was around 167 cm ( ) (Boddington, 1996: 177). Analysis of the cemetery as a whole indicated that 72% of all adult males were buried with some form of stone arrangements and 48% were buried with stone head pillows. In zone 5, 67.4% of males were buried with some form of stone arrangement, and Boddington (1996) noted that these were generally more complexly arranged than in the rest of the cemetery. Skeleton 5046 is atypical because his grave contained no stones. Like 34.5% of all the burials in this zone, skeleton 5046 was buried with the lower limbs together and the upper limbs placed at the sides of the body in an east west orientation (with the head to the west). The lack of disarticulation and internal or external bone tumble suggests that the body was placed directly in the ground without a coffin. General pathology This individual was shown to have extreme asymmetry in the upper body, with the right side being far more developed than the left. The right Figure 1. The locations of zones and rows within the Raunds churchyard, after Boddington (1996: Fig. 5, p.7). (Reproduced by kind permission of English Heritage.).

3 118 B. R. Upex and C. J. Knüsel humerus is longer than the left by 12 mm and, at its narrowest point, has a circumference that is greater by 4 mm. The attachment for M. deltoideus on the humerus is also enlarged on the right, with the greatest breadth at this point being 3 mm greater than that on the left. There is also the presence of a cortical defect on the attachment for M. pectoralis major on the right humerus, indicating that this muscle was repeatedly used and placed under mechanical stresses which were not present in the left humerus. The individual also had a well-healed rib fracture and a greenstick fracture of the right femur with secondary sclerosing osteomyelitis. Pathological changes in the maxilla and manual and pedal elements, combined with extensive periostitis of the lower limbs, indicate that he had suffered from lepromatous leprosy. Analysis of the vertebrae revealed Schmorl s nodes, intervertebral osteochondrosis, and osteophyte formation. Avulsions of the transverse processes Of greatest interest for this contribution was the presence of two small dysplastic bone fragments that had originally been identified as carpals. On closer inspection, these bones were identified as the transverse processes of the first thoracic vertebra. The tips of the transverse processes are secondary ossification centres in the vertebrae that appear at puberty and normally fuse between 17 and 25 years of age (see Figure 2) (Bass, 1995: 102; Goodear & Styles, 1999; Scheuer & Black, 2000: 209). Although skeleton 5046 was aged between 21 and 25 years at death, since all other vertebral transverse processes in this individual were fully fused to the vertebral bodies, non-fusion of those of the first thoracic vertebra to the vertebral body indicates a pathological aetiology for this condition. Both transverse processes had smooth shallow facets for articulation with the ribs, as well as slightly porous concave facets with lipping and osteophyte formation around them for articulation with the vertebral body (see Figures 3 and 4). While both sides of this vertebra had suffered taphonomic damage, the bones could be re-united on the right side through a false facet Figure 2. The secondary ossification centres of the vertebrae. (see Figure 5). This was not possible on the left side due to the extent of post-burial damage. Since all other transverse processes were present on the remaining vertebrae, it can be assumed that the second bone fragment also derived from the first thoracic vertebra. Aetiology There are three potential explanations for the occurrence of this lesion. The first is that an

4 Vertebral Avulsions 119 Figure 3. The transverse processes of the first thoracic vertebra. This figure is available in colour online at www. interscience.wiley.com/journal/oa. unidentified congenital condition led to the tips of the transverse processes never fusing to the main vertebral body. However, an extensive literature review has found no evidence in modern clinical literature to indicate any known congenital or developmental defects that would cause this to occur. The second option is that the epiphyses were avulsed from the vertebral body before they had fully fused. Avulsions of the transverse tips are common in modern clinical literature and can be caused by a variety of mechanisms including mechanical overloading and trauma (Schmorl & Junghanns, 1971: 260). A modern clinical example of an avulsion fracture of a thoracic transverse process is shown in Figure 6. This example is taken from a champion juvenile water-skier. The constant traction stress on the upper limbs and back caused by the skiing led to the avulsion of the transverse processes in several of the upper thoracic vertebrae in this individual. The third and final possibility is that the epiphyses had fully fused, but that there was then a bilateral fracture of the transverse processes. Fractures of this sort are commonly the result of extreme rotation, violent muscle contraction or lateral bending of the spine as a result of high impact, as in car accidents. The transverse processes of the upper thoracic vertebrae are muscle attachments for Mm. levatores costarum, Mm. rotatores and the muscles of the erector spinae group, all of which are involved in lateral flexion, extension and rotation of the trunk (Stone & Stone, 2003: 71 96). Due to constant movement produced by these muscles, the separated fragment of bone would never have had the Figure 4. The vertebral body without transverse processes. This figure is available in colour online at www. interscience.wiley.com/journal/oa.

5 120 B. R. Upex and C. J. Knüsel Figure 5. The right transverse process articulated with the vertebral body. This figure is available in colour online at opportunity to heal and so a false joint formed. This is often seen in clay-shoveller s fractures, which can take the form of either a fracture or an avulsion of the epiphysis of the vertebral spinous process. Examples of clay-shoveller s fractures are known in the archaeological record, and an individual from Chichester (Chichester 18) possessed a juvenile form of this condition, Figure 6. A modern example of a stress fracture of the transverse process of a thoracic vertebra (Goodear M, Styles S Stress fractures of the thoracic spine transverse processes in a water skier. Clinical Nuclear Medicine 24: Reproduced by kind permission of Lippincott, Williams & Wilkins Publishers).

6 Vertebral Avulsions 121 Figure 7. The smooth facet of the right transverse process. This figure is available in colour online at www. interscience.wiley.com/journal/oa. referred to as Schmitt s disease: an avulsion of the vertebral spinal epiphysis (Knüsel et al., 1996: 430). Discussion A bilateral fracture of the transverse processes of this individual s first thoracic vertebra would appear to be unlikely given the appearance of the false facets. A fracture of the transverse processes would lead to a porous surface on the false facet; whereas, the facets on the transverse processes of this individual are smooth (see Figure 7), as on an unfused epiphysis and very similar in appearance to the false facets seen in the juvenile form of clay shoveller s avulsion discussed above. This, combined with the lack of evidence for congenital or developmental defects, indicates that an avulsion fracture of the processes would be the most likely cause of these lesions. The presence of a green-stick fracture of the right femur with secondary infection and a well-healed fracture to a right rib suggest that this individual was subjected to some form of trauma during adolescence. While it cannot be demonstrated that these injuries occurred at the same time, it is a possibility. A twisting fall from a height could quite plausibly explain all of these injuries, including the avulsion of the vertebral transverse processes. The extensive asymmetry in the upper body and the presence of Schmorl s nodes, intervertebral osteochondrosis and osteophyte formation also indicate that, despite the young age of the individual, he had experienced considerable mechanical stress in his upper body and spine before his death. This may have contributed to the lack of healing and the formation of the false facets in the avulsed epiphysis. Avulsions of this sort, while apparently relatively common in modern patients, have not previously been identified in the archaeological record; an extensive literature search has not revealed any other known archaeological specimens of this type, thus suggesting that this

7 122 B. R. Upex and C. J. Knüsel individual provides a unique example of this type of avulsion. Acknowledgements We would like to thank Anthea Boylston, Jo Buckberry, Keith Dobney and Keith Manchester for their suggestions and advice. References Bass WM Human Osteology: a Laboratory and Field Manual, (3 rd edn). Missouri Archaeological Society: Columbia, MO. Boddington A Raunds Furnells: The Anglo-Saxon Church and Churchyard. Raunds Area Project, English Heritage Archaeological Report 7: London. Goodear M, Styles S Stress fractures of the thoracic spine transverse processes in a water skier. Clinical Nuclear Medicine 24: Knüsel CJ, Roberts CA, Boylston A When Adam delved...an activity-related lesion in three human skeletal populations. American Journal of Physical Anthropology 100: Scheuer L, Black S Developmental Juvenile Osteology. Academic Press: London. Schmorl G, Junghanns H The Human Spine in Health and Disease, (2 nd edn). Grune & Stratton: London. Stone RJ, Stone JA Atlas of Skeletal Muscles, (4 th edn). McGraw Hill: New York.