title: Clinical and biomechanical researches of polyetheretherketone (PEEK) rods for semi-rigid lumbar fusion: a systematic review.
abstract: Lumbar spinal fusion using rigid rods is a common surgical technique. However, adjacent segment disease and other adverse effects can occur. Dynamic stabilization devices preserve physiologic motion and reduce painful stress but have a high rate of construct failure and reoperation. Polyetheretherketone (PEEK) rods for semi-rigid fusions have a similar stiffness and adequate stabilization power compared with titanium rods, but with improved load sharing and reduced mechanical failure. The purpose of this paper is to review and evaluate the clinical and biomechanical performance of PEEK rods. A systematic review of clinical and biomechanical studies was conducted. A literature search using the PubMed, EMBASE, and Cochrane Library databases identified studies that met the eligibility criteria. Eight clinical studies and 15 biomechanical studies were included in this systematic review. The visual analog scale and the Oswestry disability index improved significantly in most studies, with satisfactory fusion rates. The occurrence of adjacent segment disease was low. In biomechanical studies, PEEK rods demonstrated a superior load-sharing distribution, a larger adjacent segment range of motion, and reduced stress at the rod-screw/screw-bone interfaces compared with titanium rods. The PEEK rod construct was simple to assemble and had a reliable in vivo performance compared with dynamic devices. The quality of clinical studies was low with confounding results, although results from mechanical studies were encouraging. There is no evidence strong enough to confirm better outcomes with PEEK rods than titanium rods. More studies with better protocols, a larger sample size, and a longer follow-up time are needed.
authors.affiliation: Department of Orthopedic Surgery (Spine Division), 1st People's Hospital of Taicang City, South Changshen Road 58#, Taicang, 215400, Jiangsu Province, China.
authors.forename: Chan
authors.initials: C
authors.lastname: Li
authors.affiliation: Division of Rheumatology, Huashan Hospital, Shanghai Medical College, Fudan University, 12 Wulumuqizhong Road, 200040, Shanghai, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Orthopedic Surgery (Spine Division), 1st People's Hospital of Taicang City, South Changshen Road 58#, Taicang, 215400, Jiangsu Province, China.
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Shi
authors.affiliation: Department of Orthopedic Surgery (Spine Division), 1st People's Hospital of Taicang City, South Changshen Road 58#, Taicang, 215400, Jiangsu Province, China.
authors.forename: Kai-Zhong
authors.initials: KZ
authors.lastname: Yan
authors.affiliation: Department of Orthopedic Surgery (Spine Division), 1st People's Hospital of Taicang City, South Changshen Road 58#, Taicang, 215400, Jiangsu Province, China.
authors.forename: Wei-Zhong
authors.initials: WZ
authors.lastname: Shen
authors.affiliation: Department of Orthopedic Surgery (Spine Division), 1st People's Hospital of Taicang City, South Changshen Road 58#, Taicang, 215400, Jiangsu Province, China. zryang@outlook.com.
authors.forename: Zhen-Rong
authors.initials: ZR
authors.lastname: Yang
mesh_terms: D001577:Benzophenones; D001696:Biomechanical Phenomena; D001863:Bone Screws; D004867:Equipment Design; D005500:Follow-Up Studies; D006801:Humans; D007659:Ketones; D008159:Lumbar Vertebrae / Q000601:surgery*; D010043:Outcome and Process Assessment, Health Care; D011092:Polyethylene Glycols; D011108:Polymers; D013123:Spinal Fusion / Q000295:instrumentation*; D014025:Titanium
chemical_list: D001577:Benzophenones; D007659:Ketones; D011108:Polymers; C063834:polyetheretherketone; D011092:Polyethylene Glycols; D014025:Titanium
keywords: Adjacent segment disease; Fusion rates; Polyetheretherketone (PEEK) rods; Semi-rigid fusion