From the Guidelines
Surgery is the usual treatment for a fracture of bilateral L4 and L5 pars interarticularis, but simple immobilization is appropriate when fracture fragments are small, nonarticular, or minimally displaced. A fracture of bilateral L4 and L5 pars interarticularis, also known as spondylolysis, typically requires a combination of rest, pain management, and physical therapy. The diagnosis is based on a history of trauma and focal pain on palpation and is confirmed with radiographic studies 1. Initial treatment should focus on activity modification with avoidance of activities that extend the spine, particularly sports like gymnastics, football, and weightlifting for 6-12 weeks.
- Pain management can include NSAIDs such as ibuprofen or naproxen for 1-2 weeks.
- A rigid or semi-rigid lumbar brace may be beneficial to limit lumbar extension and provide support during the healing process.
- Physical therapy should be initiated after the acute pain subsides, focusing on core strengthening, hamstring stretching, and proper body mechanics. Most patients improve with conservative management within 3-6 months. If symptoms persist beyond 6 months or if there is evidence of progressive slippage (spondylolisthesis), surgical intervention may be considered, as suggested by the American College of Foot and Ankle Surgeons 1. This condition occurs due to stress fractures in the pars interarticularis, the thin portion of bone between the superior and inferior articular processes of the vertebrae, typically resulting from repetitive hyperextension of the lumbar spine, common in adolescent athletes.
From the Research
Fracture of Bilateral L4 and L5 Pars Interarticularis
- A fracture of the bilateral L4 and L5 pars interarticularis is a type of stress fracture that occurs in the lumbar spine 2.
- This type of fracture is more common in young athletes involved in trunk twisting sports and can cause low back pain 2.
- The pathologic progression of this fracture starts with a stress reaction in the pars, progressing to an incomplete stress fracture, and then a complete pars fracture 2.
Diagnosis and Treatment
- Diagnosis of a fracture of the bilateral L4 and L5 pars interarticularis is dependent on clinical examination and radiological imaging studies such as plain radiography, computed tomography (CT) scans, and magnetic resonance imaging (MRI) scans 2.
- Treatment of this fracture is dependent on symptoms as well as radiographic stage of the lesion, with conservative management being the mainstay of treating early lesions 2.
- A comprehensive rehabilitation program that incorporates core spinal stabilization exercises can be effective in treating this fracture, and athletes should not return to sports until they are pain-free 2.
Risk Factors
- Excessive loading in repetitive hyperextension is a significant risk factor for a fracture of the bilateral L4 and L5 pars interarticularis 2.
- A steeply angled superior endplate of S1, which represents a sacral tilt, is associated with a significantly increased angle of lordosis and pars fractures at L5 3.
- Professional sporting individuals are at increased risk of failure of resolution of symptoms, which may require early surgical repair of the pars interarticularis defect 2.
Surgical Treatment
- Modified Buck's technique and pedicle screw-hook constructs for direct repair have a high success rate in patients with persistent low back pain 2.
- Minimally invasive lumbar pars defect repair has given similar successful outcomes with the added advantage of minimizing muscle injury, preserving the adjacent joint, and reducing hospital stay 2.
- Intraoperative intrathecal morphine has been shown to reduce postoperative opioid use and length of stay in patients undergoing posterior spinal fusion 4.