A Mechanism of Injury to the Forefoot in Car Crashes

Objective:The purpose of this study was to determine a mechanism of injury of the forefoot due to impact loads and accelerations as noted in some frontal offset car crashes. Methods:The impact tests conducted simulated knee-leg-foot entrapment, floor pan intrusions, whole-body deceleration, muscle tension, and foot/pedal interaction. Specimens were impacted at speeds of up to 16 m/s. To verify this injury mechanism research was conducted in an effort to produce Lisfranc type injuries and metatarsal fractures. A total of 54 lower legs of post-mortem human subjects were tested. Two possible mechanisms of injury were investigated. For the first mechanism the driver was assumed to be braking hard with the foot on the brake pedal and at 0 deg plantar flexion (Plantar Nominal Configuration) and the brake pedal was in contact with the foot behind the ball of the foot. The second mechanism was studied by having the ball of the foot either on the brake pedal or on the floorboard with the foot plantar-flexed 35 to 50 deg (Plantar Flexed Configuration). Results:The Plantar Nominal injury mechanism yielded few injuries of the type the study set out to produce. Out of 13 specimens tested at speeds of 16 m/s, three had injuries of the metatarsal (MT) and tarsometatarsal joints. The Plantar Flexed Configuration injury mechanism yielded 65% injuries at high (12.5–16 m/s) and moderate (6–12 m/s) speeds. Conclusion:It is concluded that Lisfranc type foot injuries are the result of impacting the forefoot in the Plantar Flexed Configuration. The injuries were consistent with those reported by physicians treating accident victims and were verified by an orthopedic surgeon during post impact x-ray and autopsy. They included Lisfranc fractures, ligamentous disruptions, and metatarsal fractures.

[1]  M. Benjamin.  Hollinshead's Functional Anatomy of the Limbs and Back , 1991 .

[2]  Patricia C. Dischinger,et al.  FOOT AND ANKLE INJURY: THE ROLES OF DRIVER ANTHROPOMETRY, FOOTWEAR, AND PEDAL CONTROLS , 1996 .

[3]  P C Dischinger,et al.  Lower limb response and injury in frontal crashes. , 1998, Accident; analysis and prevention.

[4]  Edward B. Elmer,et al.  Surgery of the Foot and Ankle , 1990 .

[5]  K B Fields,et al.  Lisfranc injury of the foot: a commonly missed diagnosis. , 1998, American family physician.

[6]  Winfried Buss,et al.  SIMULATION OF FOOTWELL INTRUSION FOR SLED TESTING , 1998 .

[7]  Diane C. Lestina,et al.  Mechanisms of Fracture in Ankle and Foot Injuries to Drivers in Motor Vehicle Crashes , 1992 .

[8]  Claude Tarriere,et al.  BIOMECHANICAL RESPONSE AND PHYSICAL PROPERTIES OF THE LEG, FOOT, AND ANKLE , 1996 .

[9]  P C Dischinger,et al.  Lower extremity fractures in motor vehicle collisions: the role of driver gender and height. , 1995, Accident; analysis and prevention.

[10]  N. Murphy,et al.  Lisfranc joint injuries: trauma mechanisms and associated injuries. , 1994, The Journal of trauma.

[11]  Rolf H. Eppinger,et al.  Ankle joint injury mechanism for adults in frontal automotive impact , 1991 .

[12]  P C Dischinger,et al.  Lower extremity injuries in drivers of airbag-equipped automobiles: clinical and crash reconstruction correlations. , 1995, The Journal of trauma.

[13]  H. Aro,et al.  Lisfranc joint injuries: trauma mechanisms and associated injuries. , 1993, The Journal of trauma.

[14]  P. Lövsund,et al.  AN INFLATABLE CARPET TO REDUCE THE LOADING OF THE LOWER EXTREMITIES - EVALUATION BY A NEW SLED TEST METHOD WITH TOEPAN INTRUSION , 1998 .

[15]  J. Brunet.  Pathomechanics of Complex Dislocations of the First Metatarsophalangeal Joint , 1996, Clinical orthopaedics and related research.

[16]  S. Trevino,et al.  Controversies in tarsometatarsal injuries. , 1995, The Orthopedic clinics of North America.

[17]  E. S. Alepuz,et al.  Fractures of the Central Metatarsal , 1996, Foot & ankle international.

[18]  M Goossens,et al.  Lisfranc's fracture-dislocations: etiology, radiology, and results of treatment. A review of 20 cases. , 1983, Clinical orthopaedics and related research.

[19]  Albert I. King,et al.  Dynamic human ankle response to inversion and eversion , 1993 .

[20]  N Yoganandan,et al.  Axial impact biomechanics of the human foot-ankle complex. , 1997, Journal of biomechanical engineering.

[21]  Yuichi Kitagawa,et al.  A Severe Ankle and Foot Injury in Frontal Crashes and Its Mechanism , 1998 .

[22]  M. Richter,et al.  Fractures and Fracture Dislocations of the Midfoot: Occurrence, Causes and Long-term Results , 2001, Foot & ankle international.

[23]  Jeffrey Richard Crandall,et al.  Lower Extremity and Brake Pedal Interaction in Frontal Collisions: Sled Tests , 1998 .

[24]  Paul C. Begeman,et al.  Human ankle impact response in dorsiflexion , 1990 .

[25]  John D. States,et al.  Accident Investigation and Impairment Study of Lower Extremity Injury , 1993 .

[26]  D. Altman,et al.  Statistics Notes: Diagnostic tests 1: sensitivity and specificity , 1994 .

[27]  P. Prasad,et al.  Foot and Ankle Severity Scale (FASS) , 1997, Foot & ankle international.

[28]  J. Michelson,et al.  Foot and Ankle Injuries in Motor Vehicle Accidents , 2001, Foot & ankle international.

[29]  M. Nyska,et al.  Floating metatarsal: concomitant Lisfranc fracture-dislocation and complex dislocation of the first metatarsophalangeal joint. , 1997, The Journal of trauma.

[30]  P Vulcan,et al.  Lower limb injuries to passenger car occupants. , 1997, Accident; analysis and prevention.