This is a pilot proof of feasibility study to explore the efficacy of High Resolution Infrared Thermographic Imaging (HRTI) to assist with the detection of musculoskeletal infections in children. In HRTI, a sensitive thermal camera is used to capture the temperature profile of the suspected infected body region in the form of images. In this study, a 10-second video will be recorded to allow dynamic monitoring. The resulting video will be processed and interpreted to determine whether there is a musculoskeletal infection.

Bone, joint and soft tissue infections can be caused by bacteria which can enter the body through accidental injuries, or because of surgery or implants. Once in the body, they circulate through the bloodstream until they reach a bone, joint, or muscle, multiply and cause infection. These conditions can cause significant complications in children and adults and can even result in death if untreated.

Infections of the bone, called osteomyelitis can inhibit bone growth in children. As a result, children who have suffered from osteomyelitis may require extensive treatment later in childhood. While osteomyelitis accounts for only 1% of childhood hospital admissions, its incidence in children has increased in recent decades. This is associated with an increase in the prevalence of antibiotic resistant bacteria such as MRSA.

Infections of the joint, called septic arthritis, is an emergency condition that requires prompt diagnosis and treatment. Long delays in diagnosis and surgical drainage of the joint may lead to irreversible damage to the cartilage and bone destruction.

There is currently a need for improved technologies to screen for and monitor bone, joint, and soft tissue infections. Plain radiographs appear normal in the first 7 to 10 days of osteomyelitis. Magnetic resonance imaging (MRI) is the most sensitive modality for diagnosing osteomyelitis. However, MRI scans are costly their accessibility is limited, plus the scan can take 30 minutes to perform. As the child needs to be still during the scan, sedation is required.

Infrared thermal imaging is a harmless, cost effective and rapid scanning method that has proven industrial applications such as condition monitoring of machineries and fault findings. There has also been extensive interest in utilising and this technology for medical diagnosis and monitoring. This study builds on our earlier work that used HRTI to detect inflammation in the abdomen in infants. This technology may allow timelier and more cost-effective diagnosis of the condition. Sheffield Children's Hospital and Sheffield Hallam University collaborate in conducting the study.

The study will involve recruiting 30 patients at Sheffield Children's Hospital with suspected infection of either bone, joint or soft tissue. They will have their HRTI recorded and processed to follow up the study's research questions. The findings from the study will not alter the routine medical treatments of the patients and participation is voluntary.

Inclusion Criteria:

• Children and young people from neonates to 15 years of age:
• With clinical suspicion of a primary MSK infection (irrespective of location or aetiology), as defined by presenting symptoms, physical examination and bloodwork performed by a qualified clinician.
• Presenting to Sheffield Children's Hospital via A&E or referral from another hospital.
• Who are able to interpret the information given in the information sheet/assent form on paper in English (with the exception of children under the age of 3 years who are not required to assent.)
• With at least 1 competent legal guardian who is capable of legally consenting, and interpreting the information given in the information sheet in English.
• Where a medical doctor involved in their care has agreed that their participation in the study will not negatively impact on their treatment outcome

Exclusion Criteria:

• - Have a secondary MSK infection.
• Are severely ill or need urgent/critical attention or have comorbid conditions that will complicate their care, as decided by a medical doctor involved in their treatment.
• Patients with conditions including but not limited to leukaemia, hyper/hypothyroidism, diabetes mellitus or any other condition that affects their basal metabolic rate/body temperature.
• Amputees where the amputated region is contralateral to the region of suspected infection.
• Have received an a priori diagnosis or have already undergone any investigation. This includes patients admitted for a recurrence/exacerbation of recently diagnosed MSK infection.
• Any patient where the medical team responsible for their treatment raises concerns that HRTI could negatively impact their treatment outcome.
• The patient, or their legal guardian(s) do not consent or assent/withdraw consent or assent/ or are not able to consent or assent for any reason. (Eg. The patient/guardian(s) are non-English speakers or have disabilities impairing their understanding of the study.)

Paediatric patients ages 0-15 presenting to Sheffield Children's Hospital with a suspected primary muscoloskeltal infection