Slipped upper (or capital) femoral epiphysis (SUFE or SCFE, respectively) is not common, with an incidence of 2 in 100 000. Nevertheless, it is a very common exam topic because it has several features that can differentiate poor, average, and excellent candidates.

Congenital dislocation of the knee (CDK) is a relatively rare congenital condition where one or both knees are either hyperextended, subluxed, or dislocated. The reasons are not very well understood.

Skeletal dysplasia (SD) is a heterogenous group of inherited disorders characterized by abnormal growth of bone and/or cartilage, resulting in abnormal shape and size of the skeleton, spine, and/or head.

This chapter covers several conditions that have featured in previous exams but do not fit neatly in other chapters, including non-accidental injury, bladder exstrophy, osteogenesis imperfecta (OI), physis and physeal fractures, toe walkers, and others.

This section covers several hip problems that are not covered earlier and are relevant to the exam (and practice). More hip disorders, including hip disorders in neuromuscular conditions, trisomy 21 and skeletal dysplasia, will be covered in their relevant sections.

Assessing a child with orthopaedic problems is more challenging than assessing adults. Children are poor historians and parents are usually emotional. Establishing a rapport during the first visit (and in the exam) is essential – although not always easy or possible. It gets easier with experience though.

Gait analysis is an essential orthopaedic skill. It represents a dynamic complement to static clinical examination. It is important to remember that gait by observation requires no more equipment than stereoscopic vision. As with all other skills, it requires persistence, reflection, and experience to master.

The key to understanding metabolic bone disease in children is to have a clear understanding of what bone is made of and how it grows at the physes. The structure of the physis is covered in detail in Chapter 25. An overview of the structure of bone and its role in calcium and phosphate homeostasis will be covered below.

The ankle joint is a modified hinge joint between the tibial plafond, the medial and lateral malleoli proximally, and the talus distally. It is stabilized by several ligaments which are essential for normal function (Figure 9.1).

The foot has 26 bones, 33 joints, and over 100 muscles and tendons; therefore, it is not a surprise that it is one of the commonest causes for parents to see a paediatric orthopaedic surgeon. At birth, the talus, calcaneus, cuboid, metatarsals, and phalanges are ossified, whereas the navicular and three cuneiforms are not (see Chapter 3, Figure 3.11). The lateral cuneiform ossifies at 1 year, the medial cuneiform at 2 years, and the intermediate cuneiform at 3 years. The navicular bone ossifies between 2 and 5 years [1].

Radioulnar synostosis refers to the bony bridge between the radius and the ulna. This can be either congenital or post-traumatic. The precise cause of congenial synostosis is unknown. Embryologically, the elbow forms from the three cartilaginous parts representing the humerus, radius, and ulna. A programmed cavitation process leads to formation of the elbow joint; if this process fails, endochondral ossification results in a bony synostosis. Because the forearm bones differentiate at a time when the fetal forearm is in pronation, almost all forearm synostoses are fixed in this position.

The initial management of a child with a suspected spine injury is the same as for an adult. Advanced Trauma Life Support (ATLS) protocols of primary and secondary survey must be followed. Cervical spine protection is linked to airway management, which is the first step in managing an injured person. A paediatric spinal board should be used in children aged <8 years to avoid neck flexion due to their relatively large heads.

Septic arthritis is an intra-articular microbial infection of the joint. It typically affects large joints, such as the hip (35%), knee (35%), and ankle (10%), although other joints may be affected. Usually only one joint is affected, but multiple joint involvement has been reported.

Many of the syndromes of ‘orthopaedic interest’ rely on the clinical skills of pattern recognition and some knowledge of genetics. Increasingly, in any given patient, the genotype can be mapped and the genetic mishap identified. However, whilst this does not always improve our understanding of the patient’s phenotype, it can help our appreciation of which other systems are affected and perhaps in which way.