Development of the center of pressure velocity in the healing process after intra-articular calcaneus fractures

Abstract

BackgroundCalcaneal fractures are among the most common foot injuries and sometimes develop manifold post-surgical complications. Restricted foot movement is one of the main functional limitations which often persists during long-term rehabilitation. Therefore, it is important to quantitatively monitor the biomechanical foot mobility after calcaneal fracture from an early stage in order to achieve an optimal therapeutic treatment. Research questionEvaluation of the Center of Pressure velocity (vCOP) in patients after intrarticular calcaneal fractures during the healing progress from three to 24 months after surgery. MethodsA total of 20 patients with unilateral calcaneal fracture were investigated by means of pedobarography and marker-based gait analysis at three, six, 12 and 24 months after surgery. Data for vCOP [m/s], maximum external dorsal extension moments during stance (DEmomentstance) and tibiotalar range of motion during mid stance (MS) and terminal stance (TS) were obtained. Functional evaluation was performed using clinical examination (e.g. calf circumference measurements) and patient-reported outcome measures (SF-36). ResultsWhen compared to the healthy side, vCOP of the injured side showed a significant reduction during MS (3 months: 48%, p < 0.001; 6 months: 13%; p = 0.040) and an significant increase during TS (3 months: 110%, p < 0.001; 6 months: 43%, p < 0.001; 12 months: 17%, p = 0.012). DEmomentstance of the fractured foot, showed a significant increase of 80% (p < 0.001) from three to 24 months after surgery, which correlated with vCOP at three and six months after surgery (p < 0.05; vCOP MS: 3 months: r = 0.876, 6 months: r = 0.685; vCOP TS: 3 months: r = −0.554, 6 months r = −0.626). SignificancevCOP might serve as an indicator for foot mobility and function during the early healing phase after calcaneal fractures. As vCOP can be obtained by pedobarography it is more readily accessible an less costly compared to foot function obtained by marker based gait analysis.