DEFINITION AND SYMPTOMS
Spondylolisthesis is a degenerative, traumatic or congenital condition where one vertebra slips over the vertebrae below. The isthmic type is the most common cause of back pain in adolescents and young athletes. It is seen most commonly in the lumbar spine but it can affect the cervical and thoracic spine as well. Spondylolysis (stress fracture of Pars Interarticularis) is the cause of spondylolisthesis in congenital and traumatic types. The pars interarticularis is a small segment of vertebrae, joining the facet joints. If pars interarticularis fractures on both sides of the same vertebrae, it may lead to forward slippage of the vertebrae over the one below it, leading to spondylolisthesis. Single sided fracture may be painful but will not result in
slippage. Most common spondylolisthesis is L5/S1 followed by L4/5. Gymnasts, divers, weightlifters, football players, hockey players, and military parachutists are susceptible to spondylolisthesis since there is a forceful extension and twist force on the spine in these sports/jobs leading to pars fracture. Spondylolisthesis is graded based on the degree of the slippage. Grade 1 which is a 25% or less slippage is the most common. Spine stability is of concern in Grades 3-5 which requires surgical stabilization.
Lumbar spondylolisthesis can be acute or chronic. Back pain with spine extension is the main complaint, but it also can present with groin pain, buttock pain, hamstring pain, sciatica lower leg pain, muscle tightness, leg/foot numbness and leg weakness.
Cervical spondylolisthesis presents with neck pain, shoulder blade pain or headaches. Pain is triggered by neck movement (extension and side bending or turning). Due to compression of spinal nerves or spinal cord, the patient may also have arm pain, arm/hand numbness, tingling, electrical sensation or myelopathy (losing dexterity, imbalance, loss of muscle function, incontinence and falls).
The congenital spondylolisthesis (isthmic type) is typically not diagnosed till later in life when it becomes symptomatic. The degenerative listhesis present at or after 4th decade of life and the traumatic ones present in the context of the trauma. The first episode is often acute and patients go to the emergency room. At the ER, a clinical diagnosis is made based on x-rays and physical examination. If there is no progressive neurological loss, further care is deferred to the primary care physician and/or spine specialist in an outpatient setting. The spine specialist will examine the patient and determine proper workup. A thorough physical examination is performed by the spine specialist, which includes range of motion examination, sensory testing, strength testing and evaluation of reflexes. If there are alarming signs of spinal cord compression, a more aggressive workup is warranted. The first diagnostic test is often an x-ray, including dynamic x-rays to assess stability of the spine. The most accurate clinical test to identify the pars fracture is a CT scan. An MRI can identify a pars fracture in the acute phase. To evaluate nerve impingement and cord compression, MRI is a superior test. In the acute phase, a bone scan can identify the pars fracture which is critical in the return to competitive sports.
Avoiding aggressive spine extension, staying away from lifting over 10-20 lbs and keeping athletes out of competition for the first few months can help with progress. In adolescence or adults with a newly developed pars fracture, custom bracing is prescribed for 2-6 months which may result in solidifying the fracture line and prevent spondylolisthesis. Bracing in general provides pain relief in the acute phase but long-term use is not recommended. Pain can be controlled by nonsteroidal anti-inflammatory medication, Tylenol or a short course of stronger pain medication. Muscle pain and spasms can be controlled by muscle relaxants. If there are no alarming neurological deficits or spine instability, 6-8 weeks of physical therapy is recommended.
The patient and physical therapist work on strengthening exercises, isometric and isotonic exercises, as well as stretching and balance enhancing techniques to minimize symptoms and improve function. In most cases, this conservative treatment results in improvement of symptoms. After physical therapy treatment, the patient is re-examined to evaluate for any residual deficits. If the pain subsides and function fully recovers, the patient is discharged with a recommendation to continue a home exercise program and observe correct ergonomics. Return to sports and competition is determined by physicians and may require follow-up imaging. The percentages of athletes who return to sports activities after conservative and surgical treatment appeared to be satisfactory (80% or more), but the interval until their return to sports activities was longer after surgery than after conservative treatment. There is limited research data available to support or confirm the safety of spine manipulation (chiropractic) in high grade spondylolisthesis therefor it is not recommended.
Pain and dysfunction may not improve with oral medications or physical therapy. In those cases, an x-ray guided epidural steroid injection can help with the sciatica or arm pain, facet injection or pars injection can help with localized lower back pain, or a radiofrequency ablation treatment can help localized spinal pain. The effect of spinal injections and procedures may last several weeks to several months. If the symptoms return, such treatment could be repeated.
Persistent pain, unstable spine, progressive weakness, myelopathy (cord compression) and frequent falls are among the indications of surgical care. A careful risk assessment should be done by the primary care physician, spine surgeon and the patient before considering surgery. Spinal fusion is the recommended procedure for spondylolisthesis to help back/neck pain and relieve the pressure off the nerves or spinal cord. Surgery takes a few hours to complete, with a course of inpatient hospitalization and a few months of outpatient rehabilitation after discharge from the hospital. Patients should avoid smoking for 6 months after fusion surgery, as it interferes and would result in non-fusion.