Clinical Results and Functional Outcomes After Direct Intralaminar Screw Repair of Spondylolysis

Study Design. 

Prospective analysis.

Objective. 

Our objective was to analyze clinical and functional results of patients with spondylolysis treated via direct intralaminar screw fixation and autograft, a minimally invasive and motion-preserving surgery.

Summary of Background Data. 

Spondylolysis is usually treated nonoperatively; multiple surgical techniques are available when nonoperative measures fail. No studies evaluate the clinical and functional outcomes and their correlation with pars defect size and disc morphology on magnetic resonance imaging.

Methods. 

We reviewed patients with spondylolysis treated with intralaminar screw fixation and bone grafting from 2000 through 2010. Of the 31 patients (mean age, 16 yr; range, 10–37 yr), 25 (81%) were competitive athletes. Preoperative computed tomographic scans were used to measure the pars defect size, and preoperative magnetic resonance images were graded using Pfirrmann classification for correlation with postoperative outcomes. Student t test was used for analysis (significance, P < 0.05).

Results. 

At a mean follow-up of 60 months (range, 24–135 mo), pain (visual analogue scale score) significantly (P < 0.01) improved: preoperative mean, 7 points (range, 1–10 points); postoperative mean, 2 points (range, 0–10 points). Of the 25 athletes, 19 (76%) returned to competitive sports with a mean postoperative visual analogue scale score of 1 point (range, 0–4 points) at a mean of 6 months (range, 3–10 mo) after surgery. One patient required L6–S2 posterior spinal fusion after spondylolysis repair for persistent pain starting 18 months after intralaminar screw fixation, 2 patients sustained unilateral intralaminar screw fractures at L5, and 1 patient required irrigation and debridement for a superficial postoperative infection. There was no correlation among preoperative magnetic resonance imaging disc morphology, defect size on computed tomography, patient age, and clinical outcomes.

Conclusion. 

Direct repair of spondylolysis with intralaminar screws offers a low profile, reliable treatment with good functional outcome and a low complication rate in active patients.

Level of Evidence: 4

We describe the clinical results and functional outcomes and investigated the correlation between pars defect size and intervertebral disc morphology on magnetic resonance imaging to patient outcomes in 31 patients undergoing direct intralaminar screw fixation of pars defect, a minimally invasive and motion-preserving surgery with successful outcome and low complication rate.