Orthopaedic
CASE 80: a limping ChilD
history
A 13-year-old boy presents to his GP with an 8-week history of an ache in the left thigh. Over the past few days this has got worse and now he is complaining of groin pain and has developed a pronounced limp. He is unsure but his worsening symptoms may have coincided with a fall while playing football. He is feeling well and reports no back or neurological symptoms. His past medical history is unremarkable and he takes no regular medication.
examination
His pulse and blood pressure are within the normal range and he is afebrile. He is overweight and has a body mass index of 33. His abdominal examination is normal and there are no detectable abnormalities of the back or left knee. His left leg is held in slight external rotation. There is a restriction in abduction and internal rotation. When the hip is flexed, the leg is forced into external rotation. There is no distal neurovascular deficit.
INVESTIGATIONS
an x-ray is taken and is shown in Figure 80.1.
Figure 80.1 plain x-ray of the pelvis.
Questions
•What is the diagnosis?
•What further plain x-rays should be requested?
•What are the other causes of a ‘limping child’?
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100 Cases in Surgery
ANSWER 80
This boy has a (acute-on-chronic) slipped capital femoral epiphysis (arrow in Figure 80.2).
Figure 80.2 Slipped femoral epiphysis of the left hip.
This refers to a weakening or fracture of the proximal femoral epiphyseal growth plate. Continued shear stresses on the hip cause the epiphysis to move posteriorly and medially. This condition has a peak presentation in adolescent boys. There are a number of risk factors, including obesity, hypothyroidism and renal failure.
There are three different types described:
•Acute slip: normally secondary to significant trauma
•Chronic slip: the commonest (60 per cent) presentation with symptoms >3 weeks
•Acute-on-chronic: duration of symptoms >3 weeks with sudden deterioration
This scenario is also an excellent example of the orthopaedic mantra of examining the ‘joint above and below’ the suspected origin of the pathology. Up to half of the patients with a chronic slipped capital femoral epiphysis present with thigh or knee pain. In this case, one of the important clues in the examination is the finding of obligatory external rotation when the hip is flexed.
The AP x-ray demonstrates Trethowan’s sign. When a line (Klein line) is drawn along the superior surface of the neck, it should pass through part of the femoral head. If the line remains superior to the femoral head, then this is termed Trethowan’s sign. A frog-lateral view of the hip is normally requested to further aid diagnosis, although caution should be applied in acute presentations as this can worsen the slip. It is also worth noting that when a patient is diagnosed with a slipped capital femoral epiphysis, an x-ray of the opposite hip should be performed as a bilateral presentation occurs in one-third of patients.
At any age, a limp in a child should always be taken seriously. General points to note are: if the child is febrile or unwell, then the diagnosis of a septic arthritis or osteomyelitis should be considered. In the well child, trauma and neoplasia can occur in all age groups. The limping infant should make the clinician think of a developmental hip dysplasia, whereas in the 4–10-year age range, one should think of Perthes’ disease. Perthes’ disease is a condition where avascular necrosis of the head of the femur occurs. The presentation typically happens over a period of a month and is 3–4 times more common in boys. In up to 20 per cent of cases, both hips can be affected.
KEY POINT
• the joints above and below the presumed source of the pain should always be examined.
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Orthopaedic
CASE 81: orthopaeDiC trauma
history
A 23-year-old man is brought into the emergency department by ambulance after coming off his motorcycle. He was travelling at approximately 45 mph and hit a stationary car. A trauma call is made and you are the orthopaedic member of the trauma team. There is no other history available and he is in significant pain.
examination
The patient’s pulse is 100/min, blood pressure is 142/88 mmHg and his oxygen saturations are 97 per cent on room air. His Glasgow Coma Score has remained at 15 out of 15. He is strapped onto a spinal board. The trauma team has completed the initial assessment of the patient. The primary survey has been completed and there is no significant chest, abdominal or pelvic injury.
Examining the left leg, there is an obvious deformity. His shin is angulated at 45°. There is a wound with a diameter of 3 cm that has bone protruding through it. The pedal pulses are palpable. The distal sensation is intact.
INVESTIGATIONS
an x-ray is taken and is shown in Figure 81.1.
Questions
• What are the principles of initial assessment of a trauma patient?
• What is involved in a trauma x-ray series?
• What is the initial management for this patient’s leg injury?
Figure 81.1 plain x-ray of the left leg.
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100 Cases in Surgery
ANSWER 81
Most emergency departments have a protocol to deal with patients involved in significant trauma, which is based around the ATLS guidelines. This involves a primary survey concerned with diagnosing and treating life-threatening injuries quickly and effectively. The assessment follows an ‘ABCDE’ approach:
•A: airway with cervical spine protection
•B: breathing and ventilation
•C: circulation with haemorrhage control
•D: disability – neurological status
•E: exposure/environmental control
The trauma series of x-rays are typically comprised of an AP chest x-ray, an AP pelvis x-ray and a lateral C-spine x-ray. This combination of x-rays is aimed at picking up major injuries such as a haemothorax or pelvic fracture.
When the primary survey has been completed and resuscitation has commenced, a secondary survey is performed. This is a ‘head to toe’ examination to determine any other injuries.
In this case, the patient has sustained an ‘open’ or ‘compound’ tibial fracture. While this is not life-threatening, it is important that it is dealt with promptly. The normal principles when dealing with any fracture still apply, i.e. analgesia, stabilization, elevation, reduction and fixation. The wound should be photographed and covered with gauze soaked in an antiseptic solution. This avoids the necessity of repeated re-examinations, which would increase the risk of infection before reaching the operating theatre. Intravenous broad-spectrum antibiotics should be commenced as soon as possible, e.g. cefuroxime and metronidazole. Similarly, tetanus prophylaxis should be considered and given if necessary. Providing the patient is otherwise stable, they should be taken to theatre for wound debridement and irrigation.
KEY POINT
•the atlS protocol should be followed even in the presence of obvious limb deformity, to ensure a potentially life-threatening injury is not missed.
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