This literature review is the first article of a two-part series on the subject of spondylolysis injuries. This article summarizes two recent reviews on spondy- management and details information regarding examination, typical clinical presentation, medical recommendations, prognosis, and return to sport. The second article of this two-part series focuses on the phases of rehabilitation for spondylolysis and includes a detailed rehabilitation framework.
Introduction:
Low back pain is commonly seen in patients of all ages with variable incidence/prevalence figures reported throughout the research. Current research estimates that the prevalence of low back pain is lower in pediatric populations. However, pediatric athletic populations have considerably higher prevalence of low back pain. Low back pain diagnoses include muscle strains, discogenic pain, bone stress injuries, and more. Youth athletes with low back pain are often seen in outpatient physical therapy practice and proper management is key to maximize long-term outcomes.
Spondylolysis is a bone stress injury commonly observed at the pars interarticularis and is most common at the L5 level.1 The level of tissue damage is variable ranging from a stress reaction to a fracture. A spondylolisthesis occurs when a vertebra shifts over the vertebral body of the inferior segment. Those spondylolytic injuries that are progressive in nature commonly involve low grade spondylolisthesis at that level (estimated to be 75%).2
Pediatric low back pain prevalence is directly related to the patient’s level of participation in higher intensity sports. Current research indicates the prevalence is ~5x greater in active youth than that of inactive youth populations.1 It should be noted that prevalence is also related to factors including genetics, sex, growth, sport-specific biomechanics, and ethnicity.
A study investigating the prevalence of spondylolytic injuries in female gymnastics estimated the rate to be close to 11%. Another study investigated the prevalence of these injuries in participants of the following sports: divers, weightlifters, wrestlers, and gymnasts. They found that as a group, the prevalence is close to 15%. For reference, the estimated incidence of the average population is 5%.1
Clinical Presentation and Examination:
Spondylolysis and spondylolisthesis injuries generally include a gradual onset and are thought to be related to excessive extension and rotation of the spine.
Subjectively, the patient will likely describe pain of gradual onset over 3 or more weeks. Common findings include tenderness either unilaterally or bilaterally along the paraspinals and worsening pain with spinal extension. Patients often describe frequent and consistent use of over-the-counter anti-inflammatory medication. Pain often worsens with activity and improves with rest. Pain at rest may be indicative of more progressive spondylolysis and/or spondylolisthesis.1
Numbness and tingling or other neurological signs are typically rare with spondylolysis and should raise suspicion of other pathology. Clinicians should conduct a thorough neurologic screen for this purpose. It is recommended that therapists visualize the spine to observe for hair patches, dimpling, or skin discolorations which may rule in spina bifida occulta.1
Other important clinical findings may include limitations in muscle extensibility (hamstrings or hip flexors) or hip range of motion. Findings such as these help to direct patient treatment in the earlier phases of rehabilitation.1, 2
The “Stork Test” is a special test that asks the patient to extend through the spine while standing on one leg. The test is repeated bilaterally. A positive Stork Test is characterized by provocation of the patient’s pain upon testing. Recent studies question the clinical utility of the Stork Test, however. Diagnosis of a spondylolytic injury is multifactorial in nature and a thorough subjective history and comprehensive physical exam are more sensitive in diagnosing spondylolysis rather than solely relying on the result of the Stork Test.3
Patients should be referred out for further examination if any one of the following is true:
- There is traumatic onset and fracture is suspected
- There are neurologic changes including sensation, reflexes, or weakness in a myotomal pattern
- Pain does not respond to rest or over the counter medication
- Symptoms do not respond within 2-3 weeks following evaluation
Prognosis:
Current recommendations are that patients be placed in a full-time rigid orthosis for 4-6 weeks consistent with bony tissue healing timelines. Once the patient is asymptomatic with extension, they may begin physical therapy for a gradual return to sport over a 6 to 8-week timeline.1 Based on the degree of injury the medical team may recommend between 2 to 6 months complete rest from sport.1
Early identification is key in the course of care with spondylolytic injuries and may be predictive of future outcomes. A review found a 100% healing rate in early spondylolysis with an average treatment time of 2.5 months. The healing rate for progressive and terminal spondylolysis was found to be 93.8% and 80% respectively.1 Surgical management via either direct pars repair or fusion is recommended when patients have undergone 6 months of conservative care without resolution of symptoms.1, 2
Return to Sport Considerations:
The majority of athletes are able to return to play within 3-6 months following injury with early diagnosis and conservative treatment of spondylolysis. Retrospective studies suggest that osseous healing of spondylolytic injuries is more likely to occur in unilateral vs. bilateral injuries.1 Retrospective studies have also found that as many as 70-90% of athletes have good to excellent long-term outcomes without surgical intervention, even without radiographic evidence of osseous healing.1 In terms of spondylolisthesis, expert opinion suggests that low grade spondylolistheses (<30% slip at evaluation) are unlikely to progress further.2
As mentioned above, surgery will be indicated following 6 months of conservative treatment without resolution of symptoms. Studies have found that only 27-36% of surgeons allowed resumption of collision sports at 1-year post-op, 49% of surgeons prohibited return to collision sports with a low-grade slip (<30%), and as many of 58% prohibited return to collision sports for higher grade slips.2
Surgeons that have allowed unrestricted return to play regardless of sport included that the patient be asymptomatic, have achieved stable fusion, and have fully returned to their prior level of athletic function and capacity. These patients generally returned within 1 year post operatively.2
Conclusion:
While young athletes are at greater risk of low back pain and spondylolytic injuries relative to their inactive counterparts, early identification and management may yield favorable outcomes. This is critical in the context of maintaining activity levels through adolescence and into adulthood. This also cultivates life-long healthy habits.
In the second installment of this two-part series I will detail the rehabilitation phases of spondylolytic management. This will include considerations and exit criteria for early, mid-, and late phase rehabilitation to ensure appropriate treatment response and logical progression.
Citations:
[1] Berger, R. G., & Doyle, S. M. (2019). Spondylolysis 2019 update. Current Opinion in Pediatrics, 31(1), 61–68. doi: 10.1097/mop.0000000000000706
[2] Bouras, T., & Korovessis, P. (2014). Management of spondylolysis and low-grade spondylolisthesis in fine athletes. A comprehensive review. European Journal of Orthopaedic Surgery & Traumatology, 25(S1), 167–175. doi: 10.1007/s00590-014-1560-7
[3] Alqarni AM, Schneiders AG, Cook CE, Hendrick PA. Clinical tests to diagnose lumbar spondylolysis and spondylolisthesis: A systematic review. Phys Ther Sport. 2015 Aug;16(3):268-75. doi: 10.1016/j.ptsp.2014.12.005. Epub 2015 Jan 8. PMID: 25797410.
