The aim of this study is to design an instrumented test for the evaluation of the climb of stairs. In particular, the main purpose is to characterize and compare the performance of subjects, both pediatrics and adults, with different pathologies (cerebral palsy, amputee, Parkinson's disease, stroke and arthroplasty) in carrying out the instrumented test of climbing and descending stairs. This would provide potentially useful information to complement the clinical assessment, including investigating the existence of correlations between the instrumental data obtained and the clinical scales collected. The secondary objective is to evaluate, in a first phase of the study, the feasibility and reliability of the test, analyzing the validity of the indices obtained in terms of intra- and inter-operator reliability on healthy subjects.

In today's clinical practice there are several assessment tools available to measure strength, endurance and balance. These tools include manual testing, standardised measurement scales or disease-specific scoring systems in which the results obtained during the performance of different motor tasks are calculated to obtain an overall score reflecting the functional level. Among the most used tests, for example, we remember the Six Minute Walking Test, in which the maximum distance walked, expressed in meters, is measured in a time of 6 minutes under standardized conditions, allowing the evaluation of muscular endurance and gait aspects. In addition to tests that monitor walking abilities, there are tests for more complex activities such as climbing and descending stairs. The ability to climb stairs, in contrast to flat walking, can be considered a more challenging task, as it places greater emphasis on muscle strength of lower limbs, requires a greater range of motion of the lower limb joints and increases the demand for posture control and balance system. In addition, falls from stairs can cause more serious injury or even death than falls on a floor. Therefore, for patients with a higher risk of falling, an objective assessment of the performance of climbing stairs could be of great interest, providing fundamental support in managing the activities of the patient's daily life. In the past, a number of methods and technologies have been proposed to analyse and quantify human gait. Measurement systems range from optoelectronic systems, pressure pads or force plates to mobile sensors worn on the body such as inertial units (IMUs) or pressure pads. Mobile gait analysis systems based on IMU, in particular, are attracting increasing interest for use in long-term assessments that can be easily performed in clinical practice. Similarly, inertial sensors could be adopted for an objective evaluation of the ascent and descent of ladders thanks to adapted step analysis algorithms capable of segmenting, parameterizing and classifying the ascent and descent of ladders. The aim of this study, therefore, is to design a test for the evaluation of climbing stairs based on the use of wearable sensors. In particular, the main objective will be to characterise and compare the performance of subjects with different pathologies, providing potentially useful information to complement clinical evaluation. The secondary objective of the study will be to analyse the reliability of the indices obtained. This work proposal is the result of collaboration between several centres: IRCCS E. Medea, IRCCS Istituti Clinici Maugeri Tradate, Pio Albergo Trivulzio and Politecnico di Milano. In particular, IRCCS E. Medea, IRCCS Istituti Clinici Maugeri Tradate and Pio Albergo Trivulzio will be responsible for the recruitment of subjects and data collection. These centres will have the support of the Politecnico di Milano for the processing of data and for the development of the algorithms necessary for the extraction of the monitored parameters from the devices used.

Common inclusion criteria for all groups:

- Ability to climb and descend 10 steps with supervision, even with handrail support.

Common exclusion criteria for all groups:

• Need for help from an operator or use of orthoses to make the stairs;
• Inability to dress the instrumentation (accelerometer/electromyograph);
• clinical condition that does not recommend the execution of scales (e.g. NYHA Class IV cardiovascular decompensation, epilepsy not controlled by drugs, serious visual disturbances...);
• inability to follow verbal instructions.

Inclusion criteria for the healthy group :

• age 4-80 years (8 subjects 4-18 years; 8 subjects 19-65 years; 8 subjects 65-80 years);
• absence of diagnosis of neurological or orthopaedic pathologies, which impair the patient's mobility.

Inclusion criteria for the PCI group :

• age range 4-18 years;
• Diagnosis of Infantile Cerebral Palsy;
• right or left hemiparesis;
• ability motor skills in levels I - III according to the GMFCS (Gross Motor Function Classification System).

Inclusion criteria for the Orthopaedic group:

• Age 65-80 years;
• postoperative postoperative hip or knee arthroplasty (in election and post-fracture, any revisions will be excluded).

Inclusion criteria for the Amputee group:

• age range from 19 to 80 years;
• Leg amputation (trans-tibial), fitted with limb prosthesis.

Inclusion criteria for the Parkinson's group:

• age range from 65 years;
• diagnosis of Parkinson's disease or Parkinsonism also on a vascular basis.

Inclusion criteria for the group Ictus Cerebri:

• Age 65-80 years;
• Aftereffects of Ictus Cerebri;
• left or right hemiparesis.