INTRODUCTION
Medical management following concussion in children and adolescents has commanded the attention of health care providers and researchers alike. The majority of individuals recover spontaneously after concussion, requiring minimal medical evaluation and intervention to safely return to functional activities. However, there is a considerable and concerning subset of individuals who report persistent symptoms past the expected timeline of symptom recovery.1–4 2 , 4 , 5 6 6–9
A commonly prescribed component of concussion management, specifically during the acute phase of injury, is physical and cognitive rest.6–11 6–9 Consensus Statement on Concussion in Sport—the 5th International Conference on Concussion in Sport, 12 13
Physical therapy (PT) has emerged as a potentially effective rehabilitation strategy to help patients reengage in preinjury activities after concussion.12 , 14–18 16
In a retrospective analysis published in 2017, investigators reported on the safety and feasibility of a multimodal, impairment-based PT program consisting of aerobic exercise, vestibular/oculomotor training, and cervical spine interventions for patients aged 12 to 20 years who experienced persistent postconcussion symptoms for 3 weeks or more after injury.12
Issues related to timing and dose of PT interventions are paramount across all areas of physical therapist practice.19
METHODS
A retrospective observational study design was conducted using medical records at a large metropolitan children's hospital from June 11, 2014, to January 31, 2016. Upon approval from the institutional review board, medical records of patients who received outpatient, PT services to address concussion-related complaints were identified. To be incorporated into the initial data extraction, the medical record had to include (1) a physician-verified medical diagnosis of concussion, (2) documentation of a formal referral for outpatient impairment-based PT interventions with the episode of care terminating prior to January 31, 2016, and (3) no history of a medical condition that mimics the signs and symptoms of prolonged concussion symptoms (eg, history of chronic headaches, depression, cardiovascular conditions). Patients with prior history of concussion were included in the analysis, but previous history and the number of prior concussions were noted to help describe the sample. The initial data pool was screened further using the following exclusion criteria: (1) younger than 12 years of age at the time of the initial PT evaluation, (2) no data available beyond the initial PT visit, (3) incomplete data for the initial visit symptom score or final visit symptom score, and (4) insufficient documentation or evidence of poor adherence with the PT assessment and intervention protocols. Twelve years of age was selected as a cutoff to ensure consistency in the symptom outcome measure used because the protocol at the institution called for younger children to be assessed using a different version of the symptom inventory form.
Patient Profiles
Demographic information obtained from the medical records included date of injury, age at the time of evaluation, sex, prior history of concussion, and athlete versus nonathlete status. Patient records were categorized into 3 cohorts on the basis of the timing of PT implementation: 0 to 20 days following injury (early intervention), 21 to 41 days following injury (middle intervention), and 42 or more days following injury (late intervention). The rationale for the timing groups was based on a desire to build upon previous studies that focused on initiation of PT 3 or more weeks after injury.12 , 15 , 20 15 , 18 , 20 , 21 13
Outcome Measures
Total symptom severity score on the Post-Concussion Symptom Inventory (PCSI) was used as the primary outcome measure. The PCSI is a self-reported measure of 21 postconcussion symptoms on a 7-point Likert scale.22 , 23 21
To evaluate the safety of PT interventions provided, each patient's medical record was evaluated for any occurrences of unplanned visits to a health care provider, urgent care center, or hospital emergency department. An unplanned visit to a health care provider was flagged as a potential adverse event if it was related to an exacerbation of symptoms that had occurred within 7 days of an in-clinic PT session or completion of PT exercises at home. The duration of the PT episode of care was determined from the date of the initial visit to the date of the final visit; the date of the final visit was determined by the documentation of discharge from the treating physical therapist or by the visit date after which the patient did not return to PT within 1 month of the prior visit (categorized as self-discharge).
PT Evaluation and Interventions
Patients were evaluated and treated by 1 of 32 licensed physical therapists who were trained to treat patients with concussion via an initial comprehensive training session with biannual refresher trainings conducted by a sports-certified PT specialist with extensive experience working with children and adolescents with concussions. Clinicians were given the opportunity to receive additional individualized training to ensure high comfort level and consistent practice patterns across the treating physical therapists. All of the evaluation strategies and intervention strategies provided in the training sessions were preapproved by internal and external physician and PT brain injury specialists and aligned well with strategies previously proposed by Hugentobler et al,17 24 , 25 26 , 27 28 Figure 1 ). As no guidelines specific to PT interventions were available at the time, the therapists were encouraged to utilize related guidelines to further guide their treatment strategies (eg, neck pain guidelines,29 30
Figure 1.: Concussion care pathway recommendations for physical therapy evaluation and treatment. PCSI, Post-Concussion Symptom Inventory.
Statistical Analysis
Descriptive statistics were computed for the sample as a whole and for each intervention cohort. Chi-square tests for independence were utilized to determine the presence of group differences in sex, athletic status, and prior concussion history. Tests for the assumptions of normality and homogeneity of variance were used to determine the appropriateness of parametric versus nonparametric comparisons between groups for age, initial PCSI visit severity scores, final visit PCSI scores, change in PCSI scores, number of PT sessions, and duration of PT episode of care. One-way analysis of variance was used to compare the groups when the assumptions for parametric testing were met, and a Kruskal-Wallis H test with post hoc analyses was used when there were concerns for a lack of normality or homogeneity of variance. An a priori α level was set at .05 to assess for statistical significance between intervention cohorts.
RESULTS
In the initial chart extraction, 173 records were identified as potential cases for this study. Of the original record set, 120 records (78 females, 42 males) were deemed appropriate relative to the inclusion and exclusion criteria. Of the 120 records identified, all were deemed to have sufficient documentation and appropriate adherence to the concussion management protocols emphasized in staff training sessions. Figure 2 provides the inclusion flow chart relative to each intervention cohort. The mean age for all of the cohorts combined was 14.77 years (SD: 1.94), with a range of 12 to 21 years and median of 14. Thirty-three individuals (27.5%) were categorized into the early intervention cohort, while 39 (32.5%) and 48 (40.0%) individuals were categorized into the middle and late intervention cohorts, respectively. Table 1 summarizes the demographic results by cohort. No significant differences were identified between intervention cohorts with regard to sex, age, prior history of concussion, or athlete versus nonathlete status (P > 0.05). Of note, the late intervention cohort had a higher rate of previous concussions (54%) than the early (36%) and middle (34.1%) intervention cohorts.
Figure 2.: Flow chart for inclusion in the analysis. PCSI, Post-Concussion Symptom Inventory; PT, physical therapy.
Table 1. -
Patient Profiles by Intervention Timing Cohort
Early Intervention (n = 33)
Middle Intervention (n = 39)
Late Intervention (n = 48)
Age, y
Range
12-19
12-19
13-21
Mean (SD)
14.94 (1.97)
15.08 (1.87)
15.61 (1.69)
Median
15
15
16
Days to PT initiation
Range
1-20
21-40
42-363
Mean (SD)
11.63 (4.90)
30.51 (5.83)
97.81 (72.27)
Median
15
32
67
Sex
19 F, 14 M
29 F, 10 M
31 F, 17 M
Athlete status (A, NA)
30 A, 3 NA
34 A, 5 NA
44 A, 5 NA
Prior concussion (Yes, No)
12 Yes, 21 No
15 Yes, 24 No
26 Yes, 23 No
PCSI initial session
Range
0-84
0-90
0-54
Mean (SD)
25.14 (15.19)
25.59 (21.09)
17.66 (15.70)
Median
19
19
13
PCSI final session
Range
0-33
0-33
0-83
Mean (SD)
5.27 (8.89)
12.03 (16.14)
14.21 (21.24)
Median
1
5
3
Change in PCSI score
Range
−80 to +7
−86 to +22
−43 to +58
Mean (SD)
−19.89 (23.21)
−13.56 (19.55)
−6.45 (17.02)
Median
−10
−12
−6.5
Number of PT sessions
Range
2-18
2-48
2-15
Mean (SD)
6.51 (4.13)
8.46 (7.78)
6.89 (3.63)
Median
6
7
7
Duration of PT care, d
Range
4-106
5-206
9-245
Mean (SD)
40.94 (28.85)
54.54 (45.12)
61.53 (46.25)
Median
36
42
52
Discharge Status (C, S)
23 C, 10 S
24 C, 15 S
32 C, 17 S
Abbreviations: A, athlete; C, clinician discharge (discharged by physical therapist); F, female; M, male; NA, nonathlete; PCSI, patients' self-reported Post-Concussion Symptom Index total scores for those patients who had scores available for the beginning of their first session and the end of their first session; PT, physical therapy; S, self-discharge.
Figures 3 to 5 provide plots of the spread of scores for PCSI measures relative to each cohort. Intervention cohorts did not statistically differ with regard to their initial (P = 0.50), final (P = 0.13), or change in (P = 0.38) PCSI scores. Although the mean and median scores for the initial and change in PCSI values appeared slightly lower for the late intervention cohort than for the early and middle intervention cohorts, a deeper analysis of the cohorts combined did not show any significant relationships among days since injury and initial PCSI score or change in PCSI (P > 0.05).
Figure 3.: Initial session PCSI scores for each patient by intervention timing group. Shewart chart for individual measures (sometimes referred to as an I chart, X chart, or Xmr chart). Each dot represents an individual. The y -axis represents PCSI total severity scores, and the x -axis is ordered sequentially by PCSI score in order from lowest to highest for each group. The dashed line represents the mean score for each group. PCSI, Post-Concussion Symptom Inventory.
Figure 4.: Final session PCSI scores for each patient by intervention timing group. Shewart chart for individual measures (sometimes referred to as an I chart, X chart, or Xmr chart). Each dot represents an individual patient. The y -axis represents PCSI total severity scores, and the x -axis is ordered sequentially by PCSI score in order from lowest to highest for each group. The dashed line represents the mean score for each group. PCSI, Post-Concussion Symptom Inventory.
Figure 5.: Change in PCSI scores from initial visit to final visit for each patient by intervention timing group. Shewart chart for individual measures (sometimes referred to as an I chart, X chart, or Xmr chart). Each dot represents an individual patient. The y -axis represents PCSI total severity scores, and the x -axis is ordered sequentially by PCSI score in order from lowest to highest for each group. The dashed line represents the mean score for each group. PCSI, Post-Concussion Symptom Inventory.
All 3 cohorts demonstrated an overall reduction in PCSI values. Even so, 13 patients (10.8%) reported higher PCSI values (ie, higher symptom burden) at the final visit compared with the initial visit (Figure 5 ). Two participants (6%) in the early intervention cohort, who both reported relatively low scores at their first visit (4 and 11 points), noted a slight increase from the first to last visit with very small magnitudes (2- and 7-point increases, respectively). Four participants (10%) in the middle intervention cohort reported increases of varying magnitudes (7-, 10-, 17-, and 22-point increases). Seven participants (14.6%) in the late intervention cohort reported increases with a wide range in magnitude (2-, 3-, 5-, 10-, 20-, 22-, and 58-point increases). Further review of the charts indicated that all of the patients with score increases in the middle and late intervention groups may have had some concussion-related impairments that may not have been directly addressable with PT interventions (ie, anxiety, depression, sleep challenges).
There were no statistical differences among the early, middle, or later cohorts identified for either the number of PT sessions (P = 0.21) or the duration of PT episode of care (P = 0.19). Figures 6 and 7 provide the spread of scores for each cohort and measure. Out of the 120 records included, 7 (5.8 %) individuals had an unplanned visit to a health care provider for symptom exacerbation within 1 week of a PT session. Three unplanned visits occurred in both the early and middle intervention cohorts, while 1 unplanned visit occurred in the late intervention cohort. Of note, all of the unplanned health care visits related to symptom exacerbations occurred at least 2 days following completion of a PT clinic or home exercise session, suggesting that the symptom exacerbations that led to the unplanned health care visits were not likely to be due to the PT exercises. Because of the low rates of adverse events, a statistical comparison between cohorts is inappropriate.
Figure 6.: Number of physical therapy (PT) sessions for each patient by intervention timing group. Shewart chart for individual measures (sometimes referred to as an I chart, X chart, or Xmr chart). Each dot represents an individual patient. The y -axis represents number of PT visits scores, and the x -axis is ordered sequentially by number of PT visits in order from lowest to highest for each group. The dashed line represents the mean score for each group. PCSI, Post-Concussion Symptom Inventory.
Figure 7.: Duration of physical therapy (PT) episode of care (days) for each patient by intervention timing group. Shewart chart for individual measures (sometimes referred to as an I chart, X chart, or Xmr chart). Each dot represents an individual patient. The y -axis represents days in the PT episode of care, and the x -axis is ordered sequentially by number of days in order from lowest to highest for each group. The dashed line represents the median score for each group.
DISCUSSION
The purpose of this study was to evaluate the safety and preliminary outcomes of the implementation of PT interventions at varying time points after injury for youth diagnosed with concussion. With the low rate of adverse events, all of which were not likely related to PT interventions, these data indicate that multimodal, impairment-based PT is likely safe, regardless of the timing of initiation. In addition, the results indicate that patients receiving PT interventions can experience improvements in their symptoms, irrespective of how early or late initiation of PT occurs. Collectively, the results of this study suggest that multimodal PT interventions administered by licensed physical therapists may be feasible and safe even within the first few weeks after injury to help facilitate prompt recovery and mitigate the onset of secondary effects from delayed treatment.
Previous research illustrates the importance and effectiveness of PT interventions in facilitating recovery for patients presenting with concussion-related impairments.12 , 14 , 16 , 31 12 , 15–17 , 20 , 32 6 , 24 , 33 10 , 31 , 34 , 35
As described in the introduction, Grabowski et al12 36 36 36
For the current study, the total number of PT sessions and the duration of PT services were also similar across intervention cohorts. These results, coupled with the similarity in improvements in symptoms across cohorts, suggest that introducing PT earlier in the recovery process may be beneficial in minimizing the potential burden of longer recovery trajectories. If patients can safely participate in PT within 3 weeks following injury, as the results of the current study suggest, a logical next step is to investigate whether earlier initiation of PT interventions can help reduce the risk for prolonged recovery and facilitate earlier return to preinjury functional levels. Future studies exploring the rate of recovery and return to preinjury functional participation may provide further insight into the advantages and disadvantages of earlier initiation of PT services.
Several limitations need to be considered before applying the evidence of the current study to the treatment of patients diagnosed with concussion. First, the study's design as a retrospective analysis prevents the formation of a definitive conclusion with regard to safety and tolerability following early implementation of PT. Limited patient information was available when reviewing medical records, including confirmation of full completion of recommended episode of care, level of adherence to provider recommendations, and the precise PT intervention protocols each patient received. Likewise, unless the patient was seen directly in the health system, or a patient self-reported and a clinician documented that an unplanned health provider visit occurred, there is potential that unplanned visits to health care providers for symptom exacerbations were missed. In addition, there was a large variation in physician referral patterns for initiating PT services after concussion, which allowed for the current study to explore timing variables. However, it is possible that there was a selection bias with regard to the timing in which physicians referred patients for PT services after concussion. Physicians may have intentionally or unintentionally screened out patients, using clinical judgment, who may not be ready to safely engage in progressive, monitored physical activity.
It is also important to acknowledge that licensed physical therapists are all trained to work with patients with a variety of health conditions, and specifically brain injuries across the spectrum of severity. However, it is important to consider that the patients in this study were all being treated by physical therapists who were trained and experienced in managing patients with pediatric concussions. Future research is needed to determine how physical therapists' level of training and experience specific to working with patients with concussions may influence the overall success rates and outcomes. Another limitation to the study is that retrospective design constrained the ability to accurately capture and report on any additional services or interventions patients received (eg, medication, occupational therapy, psychological interventions) unless the therapists directly asked and documented it within the patient's medical record. In addition, due to the lack of control group, it cannot be determined whether improvements in symptoms that patients experienced were a result of the PT interventions, other interventions they may have received along the way, or natural recovery processes.
A final limitation of note is that the sample size for this study, although larger than previous studies related to this topic, may have had limited the statistical power to capture differences between the cohorts. A post hoc power analysis using Cohen d of 0.2 and 0.5 estimated effect sizes and a 95% confidence level for capturing differences between the cohorts indicated a statistical power ranging between 0.58 and 0.98 based on the size of the current sample. However, this represents a large range in power, and some statistical experts do not consider a post hoc analysis appropriate for representing observed power in a study.37
CONCLUSIONS
The current study provides evidence for the feasibility of incorporation of multimodal impairment-based PT earlier into the concussion plan of care, specifically within 3 weeks postinjury. The timing of PT services is an important component to consider when determining the most appropriate care for this patient population as there is growing concern regarding the negative effects of prolonged physical and cognitive rest. Future research should aim to validate the results of this exploratory study through prospective clinical trials in order to identify the most optimal and appropriate plan of care for this patient population.
ACKNOWLEDGMENTS
The authors acknowledge the contributions of the physical therapists and staff on the sports and orthopedic team at Cincinnati Children's Hospital for their commitment to diligently document and adhere to the suggested concussion management protocols and trainings. The authors also thank the reviewers and editors for their time and contributions to improving the reporting of the study results.
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