It was hypothesized that, by adding progressively increasing complexity of core exercises over an 8-week period, participants would experience less pain and improved function equal to or greater than the control groups (ITB stretching and conventional exercise). Baker and Fredericson found that, at 6 weeks, 22 of 24 runners were pain free and had returned to running, and suggested that 6 weeks should be the benchmark to consider whether a given treatment modality has been effective in those with ITBS [2]. A thorough search of the relevant literature yielded no studies comparing the effect of different exercise regimes among female runners.
The study results showed that neither 8 weeks of stretching of hip nor core strengthening significantly influenced the YBT™, DN muscle testing, LEFS, NPS, and SLMS indices, which may be attributed to the small sample size and short rehabilitation periods. However, all three exercise regimens produced improvements in clinical outcomes including pain, function, and strength; with the stretching and experimental group showing the greatest differences.
Within group comparison showed that, in the experimental group, a total of 13 outcome parameters showed significant differences. On the other hand, the stretching group and the conventional group showed significant differences for only five and three parameters, respectively. Thus, these results indicate that the experimental exercise regimen could be more beneficial for patients with ITBS than conventional exercises.
Traditional rehabilitation, which employed a mixture of isolated hip exercises, NSAIDs, icing, and reduction of aggravation has previously demonstrated to show improvement [27]. However, the effectiveness of these treatments varies according to the stages of ITBS during which each intervention manifested a maximum period of effectivenesss [12]. Thus, the findings of the study by Ellis et al. were consistent with the observations from this study which showed only moderate improvement in ITBS symptoms with conventional hip exercises [12].
Reduced gluteus medius strength leads to decreased stabilization and control [2]. The weakened gluteus medius muscle is known to be the cause of lower extremity dysfunction and injuries including ITBS [2, 28]. Several exercises activate the gluteus muscle, including single leg squat, clamshell, side-lying hip abduction [29, 30]. All the above-mentioned exercises were included in the experimental group of this study. Thus, these exercises in addition to the others would have led to the activation of gluteus medius, resulting in improved function and strength associated with ITBS.
Fredericson et al. also examined 24 distance runners (14 females) with ITBS treated with stretching and hip abduction exercises and pelvic drops (6 weeks rehabilitation program) [2]. Following the treatment, there was statistically significant (p < 0.05) increase in average hip abductor torque to 10.55% BWh, a 34.9% increase in injured female runners and to 10.38% BWh, a 51.4% increase in injured male runners. At the end of 6 weeks, 22 runners were pain free. and there was no recurrence of ITBS as per telephonic follow-up after 6 months [2]. Beers et al. (2008) examined the effectiveness of hip abductor strengthening in sixteen subjects (5 men and 11 women) aged between 20 and 53 years. A statistically significant difference (p = 0.05) in the strength was observed between the affected and unaffected limbs at baseline (week 0) which disappeared at the end of 6 weeks. The increase in hip abductor strength resulted in increased physical function capacity [18].
One of the major issue that hinders the effective treatment of ITBS is the fact that the cause of ITBS is difficult to identify [7]. Although there are standard protocols for treatment, the results vary. This could result from not recognizing the root cause of an individual’s ITBS, and thus not being able to address it adequately. Therefore, it is not surprising that the five indices used in this study to evaluate the treatment success were not sufficiently discriminating. Indeed, a thorough history of each patient should be collected including training age, gender, weight, previous injuries, training surface, training schedule, recovery schedule, proper tapering before competition, foot wear (i.e., examining shoe soles for uneven wear), running surface, and mileage accumulated over short or long time periods. Following this, a biomechanical assessment of any compensatory patterns or movement asymmetries due to previous injuries or inherent skeletal muscular mechanics should be performed. These total assessments lead to a functional diagnosis complementing the orthopedic diagnosis of ITBS. A functional diagnosis can either be tissue extensibility dysfunction, stability/motor control dysfunction, or joint mobility dysfunction and may include inflammation. Therefore, a customized regimen may be crafted including (1) rehabilitation to improve stability or muscle weakness, (2) joint manipulations/mobilizations to address joint dysfunction, (3) appropriate shoe adjustments (including potential orthoses), and (4) acupuncture, soft-tissue therapy, stretching and/or instrument assisted soft-tissue mobilization.
The experimental treatment group resulted in improvement in pain, function, and strength although the improvement was not statistically significant for some of the parameters assessed. The results of the study indicate that although the experimental treatment did not show statistically significant improvements in all the parameters assessed, it resulted in improvements in function, pain, and strength among study participants. These findings are valuable because they are a product of a body of research and present a new mode of treatment intervention. The study results emphasize that future research should be conducted with the experimental procedure to assess its effectiveness in large sample size with different weight, age, gender, and other variables.
Limitations of the present study include the small sample size and the short duration of the exercise intervention. With a high number of dropouts and exclusions, we acknowledge that we did not recruit all the subjects necessary to satisfy the ex ante power analysis. However, we were stringent in our recruitment selection, so as to only include in the study subjects who fully satisfied the inclusion criteria, and were likely to finish the study. Within the limits imposed by the number of subjects recruited, we are confident that our results are valid and representative. A larger sample is recommended to detect statistical differences between and within groups. A longer study period such as 10–12 weeks would allow time for myofascial adaptations to the exercises interventions. Some of the information for adherence and use of other treatments outside of study were self-reported by the subjects, which may have affected the accuracy of the treatment outcomes. Finally, this study did not account for fatigue and pain felt after a certain distance. Some of the runners did report that they did not feel pain until after 5 km. This may have affected the results of the NRPS outcomes and the return-to-run program given as well as the functional questionnaire. Further research is needed to compare the experimental exercise regimen and its effects on running biomechanics and fatigue. However, this was an exploratory study and based on the study findings a power calculation was performed and it was determined that a sample size of 12 patients for each treatment group was required for a power of 85%.We performed a power analysis based on a t test for each coefficient estimate of an ANOVA model. The statistics of the present investigation were undertaken using a per protocol analysis, since the dropouts were removed in the analysis. This study acknowledges that the intention to treat analysis is generally a more robust analysis, but emphasize that there was roughly an equal number of dropouts in each group, and the effect of removing them is not likely to change the interpretation of the results.
Although a preliminary power analysis showed that, for this pilot study, a total of 12 patients per each group would have sufficed, we are aware that such small numbers may engender a type I statistical error. However, given the nature of this preliminary investigation, the data produced should be used to inform more definitive studies.