What is the recommended treatment for a 25-year-old female with chronic low back pain and MRI findings of grade 1 anterolisthesis (anterior displacement of a vertebra) associated with chronic bilateral spondylolysis (defect in the pars interarticularis) at the L5-S1 level?

Treatment for Grade 1 Anterolisthesis with Bilateral Spondylolysis at L5-S1

Conservative management with structured physical therapy for at least 6 weeks should be the initial treatment approach, with surgical fusion reserved only for patients who fail comprehensive conservative therapy and meet specific criteria including documented instability and persistent disabling symptoms. 1

Initial Conservative Management (First-Line Treatment)

• Begin with a comprehensive 6-week structured physical therapy program focusing on core strengthening, hamstring stretching, and spine range of motion exercises 2
• Restrict activities that exacerbate symptoms, particularly hyperextension movements that stress the pars defect 3, 2
• Consider anti-inflammatory medications and activity modification as part of the initial conservative approach 1
• Studies demonstrate that 96% of patients with spondylolysis and grade I spondylolisthesis achieve minimal disability scores with conservative management alone, with 78% reporting complete resolution of pain 2

Important consideration: Bracing is no longer considered mandatory for successful outcomes, as physical therapy alone has proven equally effective while avoiding compliance issues and costs 2

Advanced Conservative Interventions (If Initial Therapy Fails)

• Epidural steroid injections at the level of the pars defect can provide significant relief in patients who fail initial conservative measures 4
• Consider neuroleptic medications (gabapentin or pregabalin) as part of comprehensive pain management 1
• Continue structured rehabilitation for a minimum of 3-6 months before considering surgical options 1, 3

Surgical Indications (Only After Conservative Failure)

Lumbar fusion should be considered only if ALL of the following criteria are met: 1

• Failure of comprehensive conservative management for at least 3-6 months including formal physical therapy 1, 3
• Documented instability on flexion-extension radiographs 1
• Persistent disabling symptoms that significantly impair function despite conservative measures 1
• Pain that directly correlates with the L5-S1 spondylolysis/anterolisthesis on imaging 1

Surgical Options When Indicated

• Fusion is recommended over decompression alone for patients with spondylolisthesis and documented instability, with fusion rates of 92-95% 1
• In select young patients with isolated pars defects and no significant disc degeneration, direct pars repair may preserve segmental motion while achieving bony fusion 5
• TLIF (transforaminal lumbar interbody fusion) is an appropriate technique for L5-S1 spondylolisthesis when fusion is indicated 1

Critical Pitfalls to Avoid

• Do not proceed to surgery without completing at least 6 weeks of formal physical therapy - this is a critical deficiency that makes surgical intervention premature 1
• Imaging abnormalities (spondylolysis and grade 1 anterolisthesis) are often present in asymptomatic individuals; correlation with clinical symptoms is essential 6
• Address modifiable risk factors (smoking, depression, chronic pain behaviors) before considering surgery, as these negatively impact surgical outcomes 7
• Recognize that fusion procedures carry 31-40% complication rates compared to 6-12% for non-instrumented procedures 1

Expected Outcomes

• Conservative management success rate: 96% of patients achieve minimal disability with structured physical therapy and activity modification 2
• Surgical fusion success rate: 86-92% clinical improvement with significant reduction in pain scores when appropriate criteria are met 1
• Most patients can return to full activity with either no symptoms (60%) or minor symptoms (40%) after appropriate treatment 5