• Siegmar Blumentritt
  • Thomas Schmalz
  • Otto Bock
Keywords: gait analysis, joint biomechanics, leg prosthesis, rehabilitation


INTRODUCTION: In current clinical practice, physical examination, X-rays and subjective impressions are the most frequent methods for evaluation of an individual’s orthopaedic condition. These familiar methods cannot predict the biomechanical function (i.e. forces, structural integrity) of joints, of a complete leg or of the locomotor apparatus. In addition to clinical evaluation more specific functional measurements of the movement apparatus, particularly during gait, seem to be desirable. This presentation illustrates our experiences with instrumented gait analysis and its efficiency as a scientific and clinical tool. The main problem is to look for sensitive parameters (indicators), which characterize the functional state of patient’s locomotor apparatus. METHODS: Our gait analysis is based on measurement of kinematic and kinetic data during level walking on a 12 m walkway, and sometimes EMG data for special cases. Measurement systems are one optoelectronical device (PRIMAS, Delft, NL) and two force plates (KISTLER, Winterthur, CH). Since 1992, 600 individuals (including amputees, orthopaedic patients and normal subjects) were measured in our gait lab. Selected systematic tests were performed with amputees, whereby different prosthetic components and prosthetic alignments were used. Also, single cases without positive clinical or X-ray findings, who complained of functional pain, received gait analysis. RESULTS: Joint moments are the single best indicators of the manner in which amputees adapt their motor activity to changes in the prosthesis. Patients complaining of pain despite negative clinical findings walk with asymmetrical muscle joint moments. Such joint moments often objectively document the patient’s rehabilitation state and his or her progress. CONCLUSIONS: The human gait cycle is a consistant and precise repeatable complex of movements performed one million times annually. Therefore, gait analysis can only be clinically useful if measurement systems can very sensitively and fastly determine external joint moments. For orthopaedic and prosthetic tasks, such measurement equipment is now available. In addition to instrumented gait analysis biomechanical knowledge is absolutly necessary so that orthopaedic patients can benefit from the valuable data of gait and motion analysis.