Response and injury severity of the head-neck unit during a low velocity head impact

Rizzetti, A.; Kallieris, D.; Schiemann, P.; Mattern, R.

Affiliations

Abstract

Skull, brain and cervical spine injuries through direct head impacts are reported.

14 head impacts (frontal, lateral or occipital and figid or padded) with cadavers and 6 padded head impacts by using Hybrid ltl and EURO-SID dummies at a velocity of 20 km/h were performed. A pneumatic impactor with a movable mass of 23 kg was used; the impact surface was a disc with 150 mm of diameter.

Accelerations at the top of the head and the epidural pressure at the contre coup site were measured. The impact situation was documented laterally with a high speed camera of a rate of 1000 pic/sec.

According to the acceleration measurements at the top of the head the evaluated acceleration at the head c.g. amounts between 70 g (padded) and 160 g (rigid); the rotational acceleration of the head around the rotation axis varies between 2700 rad/sec’ (padded) and 11000 rad/sec2 (rigid). Furthermore, the epidural pressure is between -20 kPa and -46 kPa.

The evaluated resultant acceleration in the center of gravity for padded impacts- of the cadavers is in agreement with the values observed for the dummy, whereas the HIC-values of the dummy tests are clearly higher than those of the cadavers.

Except for one test, all the rigid impacts show skull fractures. These fractures are located at the impact area and include usually the basis of the skull.

The brain injuries include contre coup subarachnoid haematom_as of different size; the haematomas were observed independent of the rigid or padded impact and were found in 54 % of the investigated cases. Possible mechanisms for causing of subarachnoid haematomas are interactions between the skull-brain interface.

Skin lacerations were observed in rigid frontal impacts and scalp contusions in occipital rigid head impacts.

It is concluded that padding prevents skull fractures but not brain injuries. Only in two cases the cervical spine was uninjured. Usually, strains of soft tissue and ruptures of ligaments were found. Response and injury mechanism are critically discussed with. those existing inthe literature.

Cited Works (6)

Year	Entry
1975	Padgaonkar AJ, Krieger KW, King AI. Measurement of angular acceleration of a rigid body using linear accelerometers. J Appl Mech. September 1975;42(3):552-556.
1980	Nahum A, Ward C, Raasch E, Adams S, Schneider D. Experimental studies of side impact to the human head. In: Proceedings of the 24th Stapp Car Crash Conference. October 15-17, 1980; Troy, MI. Warrendale, PA: Society of Automotive Engineers:45-62. SAE 801301.
1978	Got C, Patel A, Fayon A, Tarrière C, Walfisch G. Results of experimental head impacts on cadavers: the various data obtained and their relations to some measured physical parameters. In: Proceedings of the 22nd Stapp Car Crash Conference. October 24-26, 1978; Ann Arobor, MI. Warrendale, PA: Society of Automotive Engineers:57-99. SAE 780887.
1977	Stalnaker RL, Melvin JW, Nusholtz GS, Alem NM, Benson JB. Head impact response. In: Proceedings of the 21st Stapp Car Crash Conference. October 19-21, 1977; New Orleans, LA. Warrendale, PA: Society of Automotive Engineers:305-335. SAE 770921.
1980	Kallieris D, Schmidt G, Hausler E. Brain injuries under high speed loadings: a study with models and cadaver heads. In: Proceedings of the 1980 International IRCOBI Conference on the Biomechanics of Impact. September 9-11, 1980; Birmingham, England.229-240.
1984	Nusholtz GS, Lux P, Kaiker P, Janicki MA. Head impact response: skull deformation and angular accelerations. In: Proceedings of the 28th Stapp Car Crash Conference. November 6-7, 1984; Chicago, IL. Warrendale, PA: Society of Automotive Engineers:41-74. SAE 841657.

Cited By (5)

Year	Entry
2001	Gibson T, Benetatos E, Newstead S, Fildes B. Improved side impact protection: the development of injury assessment functions. In: Proceedings of the 17th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 4-7, 2001; Amsterdam, The Netherlands.
2003	van Don B, van Ratingen M, Bermond F, Masson C, Vezin P, Hynd D, Owen C, Martinez L, Knack S, Schaefer R. Biofidelity impact response requirements for an advanced mid-sized male crash test dummy. In: Proceedings of the 18th International Technical Conference on the Enhanced Safety of Vehicles (ESV). May 19-22, 2003; Nagoya, Japan.
2005	Chawla A, Mukherjee S, Mohan D, Jain S. Validation of the cervical spine model in THUMS. In: Proceedings of the 19th International Technical Conference on the Enhanced Safety of Vehicles (ESV). June 6-9, 2005; Washington, DC.
2018	Ogle MK, Carey JP, Dennison CR. Development and validation of a surrogate mechanical neck prototype for use in helmet certification applications. In: Proceedings of the 14th Ohio State University Injury Biomechanics Symposium. May 20-22, 2018; Columbus, OH.
2008	Raymond DE. Biomechanics of Blunt Ballistic Temporo-Parietal Head Impact [PhD thesis]. Detroit, MI: Wayne State University; August 2008.