Innovative ‘Push Screw’ as reduction aid for minimally invasive fixation of calcaneus fracture

• Published in: Foot & ankle orthopaedics Vol. 3; no. 3
• Main Author: Shah, Rajiv
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-07-2018; Sage Publications Ltd; SAGE Publishing
• Subjects: Fractures; Push Screw; articular fragment; Sunchondral raft screw; Minimally invasive
• ISSN: 2473-0114; 2473-0114
• DOI: 10.1177/2473011418S00434

Category:
Trauma
Introduction/Purpose:
Percutaneous reduction of depressed and rotated articular fragments is the most challenging job during minimally invasive fixation of fracture calcaneus. A solid, fully threaded, flat ended, 6.5 mm cancellous ‘Push Screw’ designed by us, serves as novel innovative tool for this purpose. ‘Push Screw’, by its pushing ability; not only reduces the articular fragment but also carries with it a big chunk of underlying subchondral cancellous bone for fixation of subarticular raft screws. We present a study of 28 cases of calcaneus fractures treated with minimally invasive techniques where ‘Push Screws’ were utilized to gain articular reduction of subtalar as well as calcaneocuboid joint.
Methods:
Twenty eight intra-articular calcaneus fracture cases where ‘Push Screw’ assisted reduction was done were included in present study. Image assisted method of achieving reduction with ‘Push Screws’ comprised of placement of a subarticular guide wire, drilling and tapping of a pilot hole, driving of a flat ended ‘Push Screw’ followed by placement of a subchondral raft screw in reduced articular fragment. ‘Push Screws’ were either replaced or retained. Sequential tightening and strategic placement of two ‘Push Screws’ helped to correct rotation as well as depression. Cases were segregated as per the joints where ‘Push Screws’ were utilized.
Results:
‘Push Screw’ assisted subtalar joint restoration was carried out in all 28 cases, while 3 cases required restoration of both; calcaneocuboid as well as subtalar joint. Use of more than one ‘Push Screw’ was required in 8 cases, out of which 3 Sander type III cases required use of three ‘Push Screws’. All these cases had involvement of both subtalar as well as calcaneocuboid joint. In 26 out of 28 cases ‘Push Screws’ were replaced with fully threaded 6.5 mm cancellous screws while in remaining 2 cases they were retained. Malreduction was noticed in 3 cases and loss of initial reduction was noticed in 2 cases.
Conclusion:
‘Push Screw’ is a novel innovative tool to achieve articular reduction at minimally invasive reduction of calcaneus fracture. It not only helps to soundly reduce articular facet but also carries with it lifted chunk of subchondral bone for sound fixation of subarticular raft screw. Ease of image aided analysis of reduction, maintenance of reduction and fixation of articular fragment are the unique advantages of ‘Push Screws’. ‘Push Screw’, a cheap and versatile reduction tool also obviates the need for trained assistant.