# HAL Training in Spinal Cord Injured Patients: A Narrative Review of 10 Years Experience
## 3 Results
### Clinical Trials
Functional testings' (10 MWT time, 10 MWT-speed, 10 MWT number of steps, TUG) improved in the higher walking ability group significantly while in the low walking ability group none of the participants were able to complete the assessments at either point. BBS score improved significantly following training in the high walking ability group but not in the low walking ability group. Barthel Index (BI) and Functional Independence Measure (FIM) as assessment of activities of daily living (ADL) were unchanged for both groups, indicating that there was no effect of training regardless of baseline walking ability [15]. The authors summed up the results such that patients with a WISCI II score below six barely benefited from training. They contrast these results with [PERSON] et al. [11] in whose collective, which improved significantly, there was also one patient with a WISCI II score of one. In [PERSON]'s study, however, individual results were not reported, so it is not clear whether this patient also improved. Interestingly, despite the sparse results in the slow walking ability group, 19 of the 20 patients reported subjective improvement after training and all patients were either fully or slightly satisfied. The issue of bladder and bowel dysfunctions raised by [PERSON] et al. [11] is revisited by [PERSON] et al. [16] in a retrospective study. Here, 35 patients with acute (\(n=13\)) or chronic (\(n=22\)) SCI completed two standardized and established gastroenterological questionnaires (Cleveland Clinic Constipation Scoring System (CCCS), Wexner Score) and a self-developed questionnaire asking for bladder function before and after completingthe training. The study protocol corresponds to that of the other Ruhr-University Bochum studies and functional results of the patients were already published. Comparisons were made for all patients and the group was divided into subgroups of acute and chronic patients. Within these subgroups, further subgroups were formed according to high or low baseline scores. Wexner Score, a questionnaire to assess the severity of fecal incontinence, over all patients and for the group of chronic patients decreased significantly. For the group of acute patients Wexner Score decreased insignificantly. Patients from both groups with higher baseline scores could decrease significantly. CCCS, a questionnaire to assess the severity of constipation, reduced non-significantly for all patients, the group of acute, and the group of chronic patients. For the subgroup of chronic patients with higher baseline scores, CCCS decreased missing out significance. The self-developed questionnaire showed an improvement in bladder function in 28.24% of all patients, 31.43% of chronic patients, and 23.08% of acute patients. The authors conclude that there is a trend toward improvement in bladder and bowel function after HAL training, with patients with higher baseline scores in Wexner Score and CCCS seeming to benefit more and see this as confirming the results of studies [28; 29; 30; 31] using other exoskeletons. However, the mixed population of acute and chronic patients and different injury levels as well as the retrospective study approach remains a limitation of this study. Another study based on the Ruhr-University Bochum protocol was published by [PERSON] et al. [17]. This time, however, the focus was not on functional improvements of the patients but on whether the functional improvements were accompanied by physiological improvements in gait. For this purpose, a 3D gait analysis was performed on 15 patients (acute \(n=5\), chronic \(n=10\)) using an inertial measurement unit sensor system. While all functional parameters improved as expected, physiological differences were also found in some phases of gait cycle showing improved knee extension during initial contact and increased maximum hip extension prior to swing phase. Furthermore, all joint angles showed a larger range of motion and those findings were accompanied by significant improvement in all spatiotemporal and gait phase parameters.