Repair of isthmic pars interarticularis fractures: a literature review of conventional and minimally invasive techniques.

INTRODUCTION The repair of symptomatic isthmic pars interarticularis fractures can result in excellent outcomes. A variety of operative interventions exist with conventional techniques requiring larger exposures. Recently described, less invasive techniques tend to minimize disruption of adjacent soft tissues, decrease postoperative pain, increase patient satisfaction, and improve return to work status and/or competitive sports. The present review details both conventional and minimally invasive techniques of pars interarticularis repairs. Also, the review uniquely describes the authors' technique of fluoroscopically guided direct pars screw placement with recombinant human morphogenic protein, with clinical and radiographic outcomes. EVIDENCE ACQUISITION A PubMed database literature review and retrospective chart review were conducted, in search of patients with lumbar spondylosis treated surgically. Literature review focused on various surgical techniques in repairing pars interarticularis fractures. Retrospective chart review analyzed demographic, radiographic, as well as pre- and postoperative clinical outcomes data. EVIDENCE SYNTHESIS Surgical technique was characterized as traditional or minimally invasive operative technique. Four major operative techniques are discussed: The Buck repair, the Scott repair, the Morscher repair, and other pedicle-screw based repairs. The Levi technique is also described, utilizing minimally invasive techniques, in full. CONCLUSIONS Surgical treatment of isthmic pars interarticularis fractures is safe and effective. Many surgical techniques exist, however minimally invasive techniques tend to provide additional clinical benefit. Moreover, fluoroscopically guided direct pars screw placement with use of recombinant human morphogenic protein, may provide the most benefit, especially in adolescent patients with high levels of physical activity.