[Quantitative evaluation of postoperative effect of calcaneal fractures using Footscan system].

OBJECTIVE: To investigate the value of using Footscan system to evaluate the therapeutic effect of two internal fixation methods on calcaneus fractures.

METHODS: From February 2006 to September 2006, 64 patients with fresh unilateral closed calcaneus fractures were randomly divided into two groups. The experimental group: 32 patients underwent minimally invasive open reduction and internal fixation with improved compressing plate and screw, including 28 males and 4 females aged 20-53 years old (average 36.7 years old); the course of disease was 3-14 days; there were 19 cases of type II, 11 of type III, and 2 of type IV according to Sanders fracture classification system. The control group: 32 patients underwent internal fixation of standard AO plate via L-shaped incision, including 29 males and 3 females aged 18-56 years old (average 37.1 years old); the course of disease was 4-15 days; there were 18 cases of type II, 11 of type III and 23 of type IV according to Sanders fracture classification system. No significant difference was noted between two groups in the general information (P > 0.05). At 1 and 2 years after operation, dynamic plantar pressure was measured using Footscan system, Maryland foot scores of two groups was compared, and statistical analysis was performed.

RESULTS: All patients were followed up for 2 years. No infection, cuticular border necrosis, and sural nerve distal end injury occurred in the experimental group, whereas in the control group, 3 patients suffered from cuticular border necrosis and recovered after dressing, and 1 patient had sural nerve distal end injury with decreased sensation in local skin. At 1 and 2 years after operation, in the control group, there were significant differences between the injured foot and the normal foot in terms of impulse, instep index, motion range of subtalar joint, lateral displacement of footplate pressure center, and calcaneal width when patients stood on both feet (P < 0.05), whereas in the experimental group, no significant differences were noted between the injured foot and the normal foot in terms of the above parameters (P > 0.05). Significant differences were noted between two groups in terms of the above parameters (P < 0.05). The Maryland score 1 year after operation was (86.74 +/- 8.56) points for the experimental group and (71.24 +/- 10.06) points for the control group; at 2 years after operation, it was increased to (87.35 +/- 8.49) points and (72.41 +/- 9.69) points, respectively, indicating there was a significant difference between two groups (P < 0.05).

CONCLUSION: Operative outcomes of internal fixation with improved compressing plate are superior to those of standard AO plate. Footscan system can provide a quantitative assessment on the operative effect of calcaneus fractures.