Pars Repair in Isthmic Spondylolysis in the Young Adults

Abstract Background Data: Spondylolysis is the main identifiable cause of low back pain in children and adolescents. The fifth lumbar vertebra (L5) is the most common site for spondylolysis. The cause of spondylolysis in these patients is attributed to repetitive stress of the pars interarticularis with subsequent microfracture;it is believed that an inherited genetic pars weakness can make an individual more susceptible to spondylolysis.There are varieties of surgical techniques in the treatment of spondylolisthesis whether the traditional surgical fusion and instrumental fixation or the direct pars repair if no evident slippage, disc degeneration or canal stenosis. Purpose: Evaluations of the efficacy of pars repair as regard bony fusion, preservation of motion segment with no adjacent level disease. Patients and Methods: our study was conducted on10 patients with diagnosed isthmic spondylolysis.Three males and seven females were operated (between 2016- 2018) by direct pars repair using smile face shaped rod technique (V shaped rod technique) with insertion of iliac crest bone graft at the site of the defect bilaterally to enhance bony fusion at the fracture site. Age less than 30years, Weight less than 80kg, back pain not responding to conservative treatment. No slippage or less than 2mm, healthy disc space not degenerated, no disc herniation or canal stenosis, no previous disc operation, preserved sagittal balance and lumber lordosis. Results: All cases were assessed clinically and radiologically over one year to assess the improvement in back pain using RMQ and to assess bony fusion radiologically through PXR and CT lumbosacral spine. Good outcome was achieved in seven cases (70% of patients) with significant improvement in back pain and RMQ. Two cases (20% of patients) had fair outcome with occasional back pain occur with sports and strenuous activities. 1 case (10% of patients) had poor out come as the patient exposed to back trauma that lead to fracture of the L5 screw and operated again for traditional surgery with 4 screws, 2 rods and cage placemen. Par bony fusion was sound in all cases except one patient that was subjected to direct back trauma 3 months following surgery and had one screw fracture, that required redo surgery with formal fixation using 4 screws, 2 rods and intervertebral cage Conclusion: Direct pars repair can provide good functional outcomes in young adult patients with isthmic spondylolysis.