Abstract
Objectives:
Spondylolysis is commonly seen in adolescent athletes with lumbar pain following acute or repetitive low back hyperextension. The diagnosis is typically confirmed with computed tomography or magnetic resonance imaging. Non-operative management and rest often lead to symptom resolution and return to sport in acute injuries. However, follow up imaging confirming radiographic healing is rarely employed. Furthermore, there is currently limited literature examining sex related differences in healing rates. The objective of this study was to investigate the relationship between sex and radiographic healing in adolescent spondylolysis cases following non-operative treatment.
Methods:
A retrospective review was conducted of adolescent cases of spondylolysis treated by a single physician between September 1, 2022, and May 1, 2024. 143 patients were initially reviewed for participation. Patients included were between 9 and 18 years old, and had a spondylosis diagnosis confirmed by a single photon emission computed tomography (SPECT) scan, and a 3-month follow-up SPECT scan. Patients who were diagnosed with chronic spondylosis or spondylolisthesis, underwent surgical treatment, or did not undergo a SPECT scan at either time point were excluded. Data collection included sex, date of birth, sports participation, and date of initial encounter. Injury-specific details such as date of injury, fracture Hollenberg grade, fracture laterality, and fracture spinal level were additionally collected. Finally, initial and 3-month follow-up SPECT imaging reports were reviewed to collect imaging modality, date, and healing status.
Results:
100 patients were included in the final analysis. The average age at the time of injury was 15.0 years old (range: 9 – 18). After 3 months of non-operative treatment, 93 fractures demonstrated some or complete healing on follow-up imaging, whereas seven (7) fractures demonstrated no healing at the same visit. No sex differences were observed between the healing and non-healing groups. Notably, all the non-healing fractures were bilateral, compared to 33 (35.5%) of the healing fractures. Table 1 demonstrates a male-dominated population at 79% with various sports participation. Grade II spondylosis made up 64% of the injuries while Grade I and III made up 9% and 27%, respectively. Table 2 displays healing results based on 3-month follow-up SPECT imaging separated by sex, fracture level, laterality, and grade. No significant changes in healing were noted based on sex or grade of spondylosis. Table 3 shows no differences in the characteristics of the spondylosis injury based on sex. Characteristics included were the average age, level of injury, laterality, grade of injury, and follow-up SPECT results of healing or not healed.
Conclusions:
Conservative treatment of spondylolysis has been shown to effectively reduce symptoms and shorten return to sport. However, there has been no such study looking at bone healing demonstrated by advanced imaging following conservative management. Our study found that the vast majority (93%) of acute adolescent spondylosis cases demonstrated radiographic healing following 3 months of conservative treatment. No differences in healing rates were observed between the sexes. This suggests skeletal maturity has a negligible effect on healing rates. These results suggest there is little reason to recommend follow up imaging of acute, unilateral spondylolysis in youth athletes. However, the substantial proportion of bilateral non-healing fractures demonstrates the additional care these injuries require.
Table 1. Study Cohort characteristics displaying differences in distribution of sex (male/female), grade of injury (I, II, III), laterality of the injury (right, left, or bilateral), level of injury (L3, L4, L5), completion of 12-week bracing, and sport participation.
