Trauma
Question 38 of 180
A 27 year old man presents to the Emergency Department complaining of leg pain following a particularly violent tackle during a football game. An x-ray is performed which shows a proximal fibular fracture. On examination the patient has weakness of ankle dorsiflexion. Which structure has been damaged?
Answer:
The common peroneal nerve may be damaged in proximal fibular injuries. Examine specifically for weakness of ankle dorsiflexion and decreased sensation of the dorsum of the foot and lateral side of the leg.Leg Injuries
Trauma
Last Updated: 25th August 2022
Tibial shaft fractures
- Adult tibial fractures are usually a result of direct blows or falls onto the tibial shaft.
- Spiral fractures of the tibia or fibula follow violent twisting injuries, usually from sports (e.g. soccer, rugby, skiing). Displaced fractures typically involve both the tibia and the fibula.
- A large portion of the tibia has relatively little soft tissue covering— compound injuries are common.
- Displaced tibial shaft fractures may be complicated by injury to the popliteal artery and compartment syndromes. Check (repeatedly) for distal pulses and sensation.
- Diagnosis is usually easy. Look for deformity, localised swelling, or tenderness. Regard all wounds near the fracture site as potential compound injuries.
- Ensure X- rays show the whole length of the tibia and fibula. Examine closely for the presence of other injuries (e.g. around the knee or ankle).
- Stress fractures can occur and may not be visible on initial X- rays. Refer if there are persisting symptoms suggestive of stress fracture.
- Treat undisplaced transverse tibial shaft fractures with analgesia and long leg POP backslab.
- Spiral and oblique fractures also need immobilisation but are potentially unstable, so refer to the orthopaedic team for admission.
- Immobilise displaced fractures in a long leg POP backslab, following IV analgesia, and refer (to consider MUA or closed intramedullary nailing). Badly comminuted or segmental fractures may require ORIF. Contact orthopaedics immediately if suspected vascular injury, sensory deficit, or gross swelling.
Toddler's fracture
- Minor trauma in 1– 4y olds may result in characteristic spiral undisplaced distal tibial fractures. The periosteum remains intact and the bone is stable.
- These may not be apparent on the initial X- rays— localised warmth and tenderness with a history of trauma may suggest the diagnosis in the otherwise wide differentials of the limping child.
- If a fracture is visible on initial X- rays, treat by rest in a POP and arrange fracture clinic follow- up.
- If the diagnosis is made without a visible fracture, treat in POP and review clinically and radiologically at 10 days— further X- rays may then demonstrate a long strip of new periosteal tibial bone formation. Continue to treat according to symptoms.
Fibular shaft fractures
- These can occur in combination with a tibial fracture, as a result of a direct blow or from twisting injuries.
- The common peroneal nerve may be damaged in proximal fibular injuries. Examine specifically for weakness of ankle dorsiflexion and decreased sensation over the dorsum of the foot, and lateral side of the leg.
- Treat undisplaced proximal or fibular shaft fractures with analgesia and elevation. Consider support with a light bandage. If unable to weight- bear, use a below- knee POP for comfort, with crutches until weight- bearing is possible. Arrange follow- up in all cases.
- Refer displaced or comminuted fractures.
- Stress fractures of the fibula are relatively common, typically affecting the fibular neck of military recruits and athletes following vigorous training. Treat symptomatically with rest and analgesia.
Maisonneuve fracture
- Transmitted forces may fracture the proximal fibula following an ankle injury. This usually involves fracture of the medial malleolus and fracture of the proximal fibula or fibular shaft, and implies damage to the distal tibiofibular syndesmosis.
- Examine the proximal fibula in all ankle injuries, and X- ray if locally tender.
Calf muscle tears
- Acute tears of the gastrocnemius muscle often occur during sports. They can also occur simply from stepping from a bus or kerb or from a sudden jump.
- Sharp or burning pain in the calf is followed by stiffness or pain on weightbearing. Examine for localised tenderness and/ or swelling over the calf muscle bellies. The medial head of the gastrocnemius is more commonly injured.
- Carefully check the Achilles tendon for signs of rupture. Differential diagnosis includes DVT or rupture of a Baker’s cyst.
- Treat with analgesia, NSAID, and initial ice application. Raising the heel with a pad may also help. Advise elevation of the leg and progressive weight-bearing, as guided by symptoms. Use of crutches may be required if symptoms are severe (in this case, arrange follow- up and early physiotherapy).
Calf muscle bruising
- Direct blunt calf trauma can result in haematoma formation and considerable swelling. Be alert to the possibility of compartment syndrome, particularly where there is a significant mechanism of injury.
Achilles tendon rupture
- Achilles tendon rupture can occur without prior symptoms during sudden forceful contraction of the calf. Usually this occurs during sports (notoriously badminton). It also occurs in other situations (e.g. running for a bus or missing a step and landing heavily).
- Patients on ciprofloxacin/fluoroquinolones or oral steroids or those with a history of steroid injection of the Achilles tendon area are at increased risk.
- The patient often describes a sudden sharp pain (‘snap’) behind the ankle. Patients may mistakenly initially believe they have sustained a blow to the back of the ankle.
- Examination
- Examination may reveal swelling, pain, bruising, and often a (diagnostic) palpable defect (gap) in the tendon ~5cm above the calcaneal insertion.
- Plantar flexion against resistance will be weaker than on the uninjured side, but do not rely on this when making a diagnosis.
- Beware plantar flexion (even standing on tiptoes) may still be possible due to action of the tibialis posterior and peroneal and toe flexor muscles.
- Calf squeeze test (Simmonds/ Thompson’s test): Kneel the patient on a chair, facing the back, with the feet hanging free over the edge. Alternatively, position the patient to lie prone on a trolley, with the ankles over the end. Gently squeeze mid- calf, and look for normal plantar flexion of the ankle. To avoid confusion, do not describe the result as +ve or –ve— just state ‘calf squeeze test normal’ or ‘abnormal’.
- Treatment remains controversial, so follow local policy. Options are:
- Conservative management: many ruptures are managed with crutches, analgesia, and immobilisation for 6 weeks in a equinus plaster, with the ankle in plantar flexion and the knee flexed to ~45°. This is followed by careful rehabilitation under the care of the orthopaedic team and physiotherapist.
- Primary surgical repair: often employed in young patients and athletes. Refer to the orthopaedic team to consider this.
- Note: sometimes a ‘partial’ Achilles tendon rupture is suspected. In this instance, the safest initial treatment is immobilisation in a non- weight- bearing below- knee POP (BKPOP) with ankle flexion, crutches, and orthopaedic follow- up. USS can help to determine the state of the tendon.
Report A Problem
Is there something wrong with this question? Let us know and we’ll fix it as soon as possible.
Loading Form...
- Biochemistry
- Blood Gases
- Haematology
| Biochemistry | Normal Value |
|---|---|
| Sodium | 135 – 145 mmol/l |
| Potassium | 3.0 – 4.5 mmol/l |
| Urea | 2.5 – 7.5 mmol/l |
| Glucose | 3.5 – 5.0 mmol/l |
| Creatinine | 35 – 135 μmol/l |
| Alanine Aminotransferase (ALT) | 5 – 35 U/l |
| Gamma-glutamyl Transferase (GGT) | < 65 U/l |
| Alkaline Phosphatase (ALP) | 30 – 135 U/l |
| Aspartate Aminotransferase (AST) | < 40 U/l |
| Total Protein | 60 – 80 g/l |
| Albumin | 35 – 50 g/l |
| Globulin | 2.4 – 3.5 g/dl |
| Amylase | < 70 U/l |
| Total Bilirubin | 3 – 17 μmol/l |
| Calcium | 2.1 – 2.5 mmol/l |
| Chloride | 95 – 105 mmol/l |
| Phosphate | 0.8 – 1.4 mmol/l |
| Haematology | Normal Value |
|---|---|
| Haemoglobin | 11.5 – 16.6 g/dl |
| White Blood Cells | 4.0 – 11.0 x 109/l |
| Platelets | 150 – 450 x 109/l |
| MCV | 80 – 96 fl |
| MCHC | 32 – 36 g/dl |
| Neutrophils | 2.0 – 7.5 x 109/l |
| Lymphocytes | 1.5 – 4.0 x 109/l |
| Monocytes | 0.3 – 1.0 x 109/l |
| Eosinophils | 0.1 – 0.5 x 109/l |
| Basophils | < 0.2 x 109/l |
| Reticulocytes | < 2% |
| Haematocrit | 0.35 – 0.49 |
| Red Cell Distribution Width | 11 – 15% |
| Blood Gases | Normal Value |
|---|---|
| pH | 7.35 – 7.45 |
| pO2 | 11 – 14 kPa |
| pCO2 | 4.5 – 6.0 kPa |
| Base Excess | -2 – +2 mmol/l |
| Bicarbonate | 24 – 30 mmol/l |
| Lactate | < 2 mmol/l |
