Common Nerve Injuries in Upper Limb Trauma

The upper limb is susceptible to various nerve injuries following trauma. Here are some of the most common nerve injuries that can occur in the upper limb:

Axillary nerve: Shoulder dislocation can cause injury to the axillary nerve, which innervates the deltoid muscle. Sensation in the skin innervated by the superior lateral cutaneous nerve can be tested as an alternative.

Radial nerve: Mid-humeral shaft fractures can damage the radial nerve, which provides sensation to the dorsum of the hand and innervates the extensor compartment of the forearm.

Ulnar nerve: Cubital tunnel syndrome and fracture of the medial epicondyle can cause ulnar nerve injury, leading to weakness in wrist flexion and a claw hand deformity.

Median nerve: Supracondylar humerus fractures, wearing a tight forearm case, wrist laceration, or carpal tunnel syndrome can injure the median nerve, causing sensory loss and motor deficits such as loss of pronation in the forearm, weakness in wrist flexion, and loss of thumb opposition.

Musculocutaneous nerve: The musculocutaneous nerve gives rise to the lateral cutaneous nerve of the forearm, while the cutaneous distribution of the median and ulnar nerves is located more distally to the hand.

In conclusion, understanding the common nerve injuries that can occur in upper limb trauma is crucial for proper diagnosis and treatment.

Common Hand Conditions: Trigger Finger, Dupuytren’s Contracture, and Osteoarthritis

Trigger Finger: A common cause of hand pain and disability, trigger finger occurs when the tendon to the finger cannot easily slide back into the tendon sheath due to swelling. This results in a fixed flexion of the finger, which pops back suddenly when released. It may be due to trauma or have no obvious cause. Treatment may include corticosteroid injection or tendon release surgery.

Dupuytren’s Contracture: This condition causes a fixed flexion contracture of the hand, making it difficult to straighten the affected fingers.

Osteoarthritis: A degenerative joint disease, osteoarthritis may cause deformity and pain in the affected joint, but not the symptoms of trigger finger.

Other possible hand conditions include cramp and tetany, which may cause muscle spasms and tingling sensations. It is important to seek medical attention for any persistent hand pain or discomfort.

Factors Affecting Blood Flow in Exercising Muscles

During exercise, several factors affect blood flow in the muscles. One of these factors is the diameter of the arterioles, which can increase due to vasodilation of muscle arterioles. Another factor is the concentration of metabolites, such as adenosine, carbon dioxide, and lactic acid, which accumulate in the tissues due to oxygen deficiency and cause vasodilation.

As a result of these factors, blood flow to the muscles can increase up to 20-fold during exercise, which is the greatest increase in any tissue in the body. This increase in blood flow is mainly due to the actions of local vasodilator substances on the muscle arterioles.

However, the increased demand for oxygen during exercise can also lead to a decrease in oxygen concentration in the tissues. This, in turn, can cause an increase in vascular resistance, which can further affect blood flow to the muscles.

Overall, understanding the factors that affect blood flow in exercising muscles is important for optimizing exercise performance and preventing injuries.

Pain Management Options for a Patient with Knee Osteoarthritis

When managing the pain of a patient with knee osteoarthritis, it is important to consider their medical history and current medication regimen. In this case, the patient is already taking non-opioids and topical capsaicin is not providing sufficient relief. According to the World Health Organization (WHO) analgesic ladder, the next step would be to add a weak opioid such as codeine or tramadol.

Offering morphine modified-release would not be appropriate as it is a strong opioid and should only be considered after trying a weak opioid first. Aspirin and ibuprofen are not recommended due to the patient’s history of peptic ulcer disease.

While a total knee replacement may ultimately be necessary to alleviate the patient’s pain, a pharmacological approach should be attempted first. This will involve assessing the patient’s fitness for surgery and anesthesia before proceeding with any surgical intervention. By managing the patient’s pain with medication, their quality of life can be improved while they await further treatment options.

The radial nerve originates from the posterior cord of the brachial plexus and runs alongside the deep brachial artery in the spiral groove of the humeral shaft. It is susceptible to damage during midshaft humeral fractures, resulting in loss of sensation on the dorsal aspect of the hand and weakness in wrist extension. The ulnar nerve is located medially to the radial nerve and is not typically affected by midshaft humeral fractures. However, it can be injured by a fracture of the medial epicondyle, resulting in weakness in wrist flexion and loss of adduction and sensation in the medial aspect of the hand. The axillary nerve branches closer to the shoulder and is prone to injury with shoulder dislocation, causing weakness in the deltoid muscle. The median nerve is not located near the midshaft of the humerus but can be injured in various ways, resulting in sensory and motor deficits. The musculocutaneous nerve passes over the brachialis muscle and can be affected by entrapment or upper brachial plexus injury, causing weakness in elbow flexion and forearm supination and sensory loss on the radial aspect of the forearm.

Management of Lower Back Pain: Explained

Lower back pain is a common complaint among patients seeking medical attention. In managing lower back pain, it is important to identify the cause and provide appropriate treatment. In this case, the patient’s back pain is most likely mechanical in nature. Mobilisation has been shown to be effective in reducing back pain, and bed rest is not advised as it can worsen the pain and affect the patient’s daily activities. A lumbar X-ray is not necessary unless there is suspicion of a fracture. Referral to physiotherapy or alternative therapies may be considered if initial management is not effective. An MRI would be indicated if there are any ‘red flags’ in the history.

Femoral Fractures: Myths and Facts

Femoral fractures are common and can have serious consequences. However, there are many myths and misconceptions surrounding these injuries. Here are some facts to help dispel these myths:

Myth: Unimpacted fractures of the femoral shaft do not cause limb shortening.
Fact: Unimpacted fractures of the femoral shaft are typically associated with shortening of the limb due to muscle contractions.

Myth: Subcapital fractures of the femoral neck do not cause avascular necrosis of the femoral head.
Fact: Intracapsular fractures of the femoral neck can disrupt the blood supply to the femoral head and cause avascular necrosis.

Myth: Pertrochanteric fractures of the femur are always associated with avascular necrosis of the femoral head.
Fact: Pertrochanteric fractures lie outside of the line of attachment of the hip joint capsule and are not typically associated with avascular necrosis of the femoral head.

Myth: Closed fractures of the femoral shaft do not cause significant blood loss.
Fact: Fractures of the femoral shaft can cause significant blood loss into the soft tissue of the thigh.

Myth: Traction splints should always be applied to distal supracondylar fractures of the femur.
Fact: Application of a traction splint to a supracondylar fracture of the distal femur may cause disimpaction of the fracture and damage to the popliteal artery.

By understanding the facts about femoral fractures, healthcare professionals can provide better care for their patients and avoid potential complications.

Nerve Anatomy of the Leg: Common Peroneal, Deep Peroneal, Superficial Peroneal, Saphenous, and Tibial Nerves

The leg is innervated by several nerves, each with its own specific functions. One of these nerves is the common peroneal nerve, which descends through the popliteal fossa and runs parallel to the biceps femoris insertion tendon. It then curves around the fibular head and neck before dividing into the superficial and deep peroneal nerves.

The deep peroneal nerve innervates the dorsiflexors of the foot, including the tibialis anterior, extensor hallucis longus, extensor digitorum longus, peroneus tertius, and extensor digitorum brevis. On the other hand, the superficial peroneal nerve supplies the peroneus longus and brevis before providing cutaneous innervation to the dorsal skin of the foot.

Another nerve that supplies cutaneous innervation to the leg is the saphenous nerve. It passes superficial to the femoral triangle and is not likely to be damaged in injuries involving the fibula.

Finally, the tibial nerve arises in the distal third of the thigh and passes deep through the popliteal fossa. It does not pass close to the fibula but instead leaves the fossa, passing through the two heads of the gastrocnemius.

Treatment Options for Smith’s Fracture

Smith’s fracture, also known as a reverse Colles’ fracture, is a type of wrist fracture where the distal radius fragment is displaced anteriorly/volarly. The following are treatment options for this type of fracture:

Reduction under local anaesthesia: This method is not recommended for best cosmetic and functional results.

Reduction under anaesthetic: This method involves either a manipulation under anaesthetic (MUA) or an open reduction and fixation (ORIF) for best cosmetic and functional results.

Application of a scaphoid cast and referral to Fracture clinic: This method is not indicated for prompt reduction and possibly fixation.

Application of a backslab plaster of Paris cast and referral to Fracture clinic the next day: This method is not appropriate for prompt reduction and possibly fixation.

Application of a backslab plaster of Paris cast and referral to Fracture clinic in 2-6 weeks: This method is not appropriate for prompt reduction and possibly fixation.

Treatment Options for Smith’s Fracture

Anatomical Snuffbox and Nerve and Artery Relations in the Wrist

The anatomical snuffbox is a triangular depression located on the lateral side of the wrist, bounded by tendons and limited above by the styloid process of the radius. The floor of the snuffbox is formed by the scaphoid and the trapezium and is crossed by the radial artery.

The radial nerve can be damaged by a midshaft humerus fracture, leading to wrist drop, but it does not pass over the anatomical snuffbox. The median nerve can be compressed when passing through the carpal tunnel, causing tingling and numbness in the hand, but it has no relation to the snuffbox. The ulnar nerve can be compressed in the cubital fossa, leading to numbness and tingling in the fourth and fifth fingers, but it also has no relation to the snuffbox. The ulnar artery is on the medial side of the wrist and has no relation to the snuffbox.