Screws versus hooks: Implant cost and deformity correction in adolescent idiopathic scoliosis

Abstract

Objective To compare the costs of two spinal implantshook and hybrid constructs and pedicle screw constructsin posterior spinal fusion for adolescent idiopathic scoliosis (AIS) as they relate to intraoperative deformity correction. Study design and method This retrospective study examined 50 patients with AIS who were treated with posterior spinal fusion using segmental hook-hybrid constructs (23) or pedicle screws (27). Radiographic parameters measured on immediate preoperative and initial standing postoperative scoliosis films were the coronal Cobb angles of the upper thoracic, middle thoracic, lumbar, and instrumented curves; global coronal and sagittal balance; thoracic kyphosis; lumbar lordosis; and type and number of implants used. Current implant cost data were obtained from three major spinal implant manufacturers to determine the total cost of the constructs, cost per degree of correction, cost per level fused, and cost per degree of correction of the major curve. Results After surgery, the average percentage of correction for the middle thoracic curve or major curve was 57 % in the hook-hybrid group compared to 73 % in the pedicle screw group (P \ 0.001). The average amount of correction of the major curve was 31.1°in the hook-hybrid group compared to 42.7°in the pedicle screw group (P \ 0.001). The average number of fused levels was 10.7 in the hookhybrid group compared to 12.2 in the pedicle screw group (P \ 0.001). The average number of implants was 14.8 in the hook-hybrid group compared to 23.3 in the pedicle screw group (P \ 0.001). The average total cost of implants was $11,248 in the hook-hybrid group compared to $22,826 in the pedicle screw group (P \ 0.001), and the average cost per fused level was $1,058 in the hook-hybrid group compared to $1,878 in the pedicle screw group (P \ 0.001). The average cost per degree of correction of the major curve was $415 in the hook-hybrid group compared to $559 in the pedicle screw group (P = 0.0014). The global coronal balance, global sagittal balance, thoracic kyphosis, and lumbar lordosis did not differ significantly between the two groups. Conclusion Pedicle screw instrumentation was shown to be more expensive overall, per fused level, and per degree of correction. Also, more implants were used and more levels were fused in the pedicle screw group than in the hook-hybrid group. Pedicle screws showed a statistically significantly greater percentage of correction of the major curve. Physicians must evaluate each patient individually and determine if the increased percentage of correction warrants the increased cost for pedicle screw constructs.

Optimal surgical care for adolescent idiopathic scoliosis: an international consensus

“…Pedicle screws versus hooks There are multiple retrospective comparative studies which report on improved coronal correction of the curve [30][31][32] and improved patient satisfaction [31] with all pedicle screw constructs versus hook-only constructs. There are reports which show increased costs [30] and increased incidence of proximal Used (67 %) Not used (13 %) Not used (24 %) Blank (7 %) Blank (9 %) junctional kyphosis [33] for all pedicle screw constructs versus hybrid and hook-only constructs.…”

“…There are reports which show increased costs [30] and increased incidence of proximal Used (67 %) Not used (13 %) Not used (24 %) Blank (7 %) Blank (9 %) junctional kyphosis [33] for all pedicle screw constructs versus hybrid and hook-only constructs.…”

Idiopatinės Skoliozės Pooperacinės Korekcijos Priklausomybė Nuo Fiksavimo Būdo

“…Multisegmentinė pedikulinė fiksacija tapo labiausiai naudojama stuburo iškrypimo korekcijos metodika. Tačiau dėl multisegmentinės fiksacijos gydymo išlaidos padidėjo 2-3 kartus [9], padidėjo komplikacijų skaičius [10][11][12], pailgėjo operacijos laikas, padidėjo kraujavimas operacijos metu [13]. Didėjant patyrimui, operacinei technikai, ryškiai sutrumpėjo operacijos laikas, kraujo netekimas operacijos metu bei komplikacijų skaičius [6,7].…”

“…studija [9], kurioje skaičiuota operacijos kaina pagal korekcijos laipsnį. Autorių duomenimis, kaina 34,7 proc.…”

Implant and spinal mobility influence on the spinal curvature correction in adolescent idiopathic Lenke I type scoliosis

“…Spinal implant constructs have developed over years from in situ fusion and cast stabilization to non-segmental rods, to segmental wire fixation, to segmental hook fixation, to segmental screw fixation and to segmental hook and screw fixation [1]. Each improvement has to be estimated, and it is important to find out which surgical technique gives the best clinical benefits to the patient.…”