Authors: Dr. Yogesh Kishorkant Pithwa,

Authors Affiliations: HOSMAT Hospital, Bengaluru

Address for Correspondence:, Flat No. D-209, USHAS Apartments,

Site No. 26, 16th Main, Jayanagar 4th Block, Bengaluru-11. India


Background; Concave apical pedicles in scoliosis are known to be narrow and dysplastic. Neural structures too, migrate towards concavity. This leaves little room for error while inserting pedicle screws. Present study aimed to assess relative advantages of inserting concave apex screws vis-à-vis other constructs.

Materials and Methods; This is aretrospective analysis of prospectively collected single-surgeon, single centre data. Patients [n=61] undergoing scoliosis surgery from September 2004-September 2013 included. Exclusion criteria: pseudarthrosis, implant failure, kyphoscoliosis and postoperative infection. Curves classified into two groups; group A-without screws anchoring concave apex and group B-with screws anchoring concave apex. Group A had varied constructs including some with sublaminar wires on concave apex and some with screws only on convex apex.

Results; Based on inclusion-exclusion criteria, 86 individual curves in 59 patients selected;group A [n=54] and group B [n=32]. Both groups comparable in terms of follow-up period, age, sex and etiology [idiopathic and non-idiopathic]. However, group A had larger [79.8+25.20]and more rigid curves [28.6% flexibility] than group B [51.8+16.30 with 51.1% flexibility]. Hence, immediate postoperative correction less significant in group A [53.8%] vis-à-vis group B[65.8%] [2-tailed p=0.0075]. However, no statistically significant difference between the two groups in terms of gains of instrumented correction over and above preoperative flexibility[group A-23.4%, group B-13.5%][two-tailed p=0.21]. At a median follow-up of 12 months, loss of correction between the two groups [A:1.4%,B:7%] not significantly different [2-tailed p=0.06]. No patient in either group had any neurological deterioration.


Over a relatively short follow-up, present study could not demonstrate any gains in using apical concave pedicle screws. A larger, prospective, multicentre study with a longer follow-up may shed more light on the risk-benefit ratio.

How to Cite this Abstract
Pithwa Y. How Advantageous Is It To Insert Screws Into Concave Apex Of A Scoliotic Curve?
International Journal of Conference Proceedings. March 2015;(2015):30