The accessory nerve provides the motor supply to the sternocleidomastoid, while the ansa cervicalis is responsible for supplying sensory information from the muscle.

The Sternocleidomastoid Muscle: Anatomy and Function

The sternocleidomastoid muscle is a large muscle located in the neck that plays an important role in head and neck movement. It is named after its origin and insertion points, which are the sternum, clavicle, mastoid process, and occipital bone. The muscle is innervated by the spinal part of the accessory nerve and the anterior rami of C2 and C3, which provide proprioceptive feedback.

The sternocleidomastoid muscle has several actions, including extending the head at the atlanto-occipital joint and flexing the cervical vertebral column. It also serves as an accessory muscle of inspiration. When only one side of the muscle contracts, it can laterally flex the neck and rotate the head so that the face looks upward to the opposite side.

The sternocleidomastoid muscle divides the neck into anterior and posterior triangles, which are important landmarks for medical professionals. The anterior triangle contains several important structures, including the carotid artery, jugular vein, and thyroid gland. The posterior triangle contains the brachial plexus, accessory nerve, and several lymph nodes.

Overall, the sternocleidomastoid muscle is a crucial muscle for head and neck movement and plays an important role in the anatomy of the neck.

To identify the affected nerve, it is crucial to accurately diagnose the underlying condition. The patient’s symptoms, such as numbness and tingling in the thumb and middle finger (and possibly the radial half of the ring finger), suggest carpal tunnel syndrome. Additionally, the patient’s occupation involving computer use and hypothyroidism are risk factors for this condition.

Carpal tunnel syndrome occurs when the median nerve is compressed at the carpal tunnel as it passes through the wrist.

Carpal tunnel syndrome is a condition that occurs when the median nerve in the carpal tunnel is compressed. This can cause pain and pins and needles sensations in the thumb, index, and middle fingers. In some cases, the symptoms may even travel up the arm. Patients may shake their hand to alleviate the discomfort, especially at night. During an examination, weakness in thumb abduction and wasting of the thenar eminence may be observed. Tapping on the affected area may also cause paraesthesia, and flexing the wrist can trigger symptoms.

There are several potential causes of carpal tunnel syndrome, including idiopathic factors, pregnancy, oedema, lunate fractures, and rheumatoid arthritis. Electrophysiology tests may reveal prolongation of the action potential in both motor and sensory nerves. Treatment options may include a six-week trial of conservative measures such as wrist splints at night or corticosteroid injections. If symptoms persist or are severe, surgical decompression may be necessary, which involves dividing the flexor retinaculum.

The radial artery is the only structure that passes through the anatomical snuffbox and is commonly injured by scaphoid bone fractures, as it runs over the bone at the snuffbox. Therefore, it is the most likely structure to be affected by such a fracture.

The median nerve does not pass through the anatomical snuffbox, but rather through the carpal tunnel, so it is less likely to be injured by a scaphoid fracture.

While the radial nerve does pass through the snuffbox, it is the superficial branch, not the deep branch, that does so. Therefore, if a scaphoid bone fracture were to damage the radial nerve, it would likely affect the superficial branch rather than the deep branch.

The basilic vein does not pass through the anatomical snuffbox, but rather travels along the ulnar side of the arm. The cephalic vein is the vein that passes through the snuffbox.

The extensor pollicis longus tendon forms the medial border of the snuffbox, but it is not one of its contents. It runs relatively superficially and is therefore less likely to be affected by a scaphoid bone fracture than a structure that runs closer to the bone, such as the radial artery.

The Anatomical Snuffbox: A Triangle on the Wrist

The anatomical snuffbox is a triangular depression located on the lateral aspect of the wrist. It is bordered by tendons of the extensor pollicis longus, extensor pollicis brevis, and abductor pollicis longus muscles, as well as the styloid process of the radius. The floor of the snuffbox is formed by the trapezium and scaphoid bones. The apex of the triangle is located distally, while the posterior border is formed by the tendon of the extensor pollicis longus. The radial artery runs through the snuffbox, making it an important landmark for medical professionals.

In summary, the anatomical snuffbox is a small triangular area on the wrist that is bordered by tendons and bones. It is an important landmark for medical professionals due to the presence of the radial artery.

The patient exhibits a positive Trendelenburg sign, indicating weakness in the gluteus medius and minimus muscles responsible for hip abduction and pelvic stabilization. This is likely due to injury to the superior gluteal nerve. In contrast, injuries to the inferior gluteal nerve affect the gluteus maximus muscle and result in difficulty rising from a seated position or climbing stairs. The femoral nerve is responsible for knee extension and does not play a role in hip abduction. The lateral cutaneous nerve of the thigh causes pain in the posterolateral aspect of the thigh but does not cause motor impairment, while the obturator nerve controls thigh adduction and does not cause a positive Trendelenburg sign.

Lower limb anatomy is an important topic that often appears in examinations. One aspect of this topic is the nerves that control motor and sensory functions in the lower limb. The femoral nerve controls knee extension and thigh flexion, and provides sensation to the anterior and medial aspect of the thigh and lower leg. It is commonly injured in cases of hip and pelvic fractures, as well as stab or gunshot wounds. The obturator nerve controls thigh adduction and provides sensation to the medial thigh. It can be injured in cases of anterior hip dislocation. The lateral cutaneous nerve of the thigh provides sensory function to the lateral and posterior surfaces of the thigh, and can be compressed near the ASIS, resulting in a condition called meralgia paraesthetica. The tibial nerve controls foot plantarflexion and inversion, and provides sensation to the sole of the foot. It is not commonly injured as it is deep and well protected, but can be affected by popliteral lacerations or posterior knee dislocation. The common peroneal nerve controls foot dorsiflexion and eversion, and can be injured at the neck of the fibula, resulting in foot drop. The superior gluteal nerve controls hip abduction and can be injured in cases of misplaced intramuscular injection, hip surgery, pelvic fracture, or posterior hip dislocation. Injury to this nerve can result in a positive Trendelenburg sign. The inferior gluteal nerve controls hip extension and lateral rotation, and is generally injured in association with the sciatic nerve. Injury to this nerve can result in difficulty rising from a seated position, as well as difficulty jumping or climbing stairs.

Fractures in the neck of the femur can be extremely dangerous, especially in elderly women with osteoporosis who experience minor trauma. However, they can also be caused by a single traumatic event.

When the femoral neck is fractured, the femur is displaced anteriorly and superiorly, resulting in a shortened leg. This displacement causes the medial rotators to become lax and the lateral rotators to become taut, leading to lateral rotation of the leg.

The blood supply to the femoral neck is delicate and is provided by the lateral and medial circumflex femoral arteries, which give off reticular arteries that pierce the joint capsule. These arteries are branches of the femoral artery.

The hip joint is supplied by two anastomoses: the trochanteric anastomosis, formed by the circumflex femoral arteries and the descending branch of the superior gluteal, and the Cruciate anastomosis, formed by the circumflex femoral, descending branch of the inferior gluteal, and ascending branch of the first perforating artery.

The femoral head has a high metabolic rate due to its wide range of movement, which stimulates bone turnover and remodeling. This requires an adequate blood supply.

Intracapsular fractures in the cervical or subcapital regions can impede blood supply and lead to avascular necrosis of the head. However, intertrochanteric fractures spare the blood supply.

Hip fractures are a common occurrence, particularly in elderly women with osteoporosis. The femoral head’s blood supply runs up the neck, making avascular necrosis a risk in displaced fractures. Symptoms include pain and a shortened and externally rotated leg. Patients with non-displaced or incomplete neck of femur fractures may still be able to bear weight. Hip fractures are classified based on their location, either intracapsular or extracapsular. The Garden system is a commonly used classification system that categorizes fractures into four types based on stability and displacement. Blood supply disruption is most common in Types III and IV.

Undisplaced intracapsular fractures can be treated with internal fixation or hemiarthroplasty if the patient is unfit. Displaced fractures require replacement arthroplasty, with total hip replacement being preferred over hemiarthroplasty if the patient was able to walk independently outdoors with no more than a stick, is not cognitively impaired, and is medically fit for anesthesia and the procedure. Extracapsular fractures are managed with a dynamic hip screw for stable intertrochanteric fractures and an intramedullary device for reverse oblique, transverse, or subtrochanteric fractures.

The surgical management of carpal tunnel syndrome involves dividing the flexor retinaculum, which is the structure spanning the anteromedial surface of the ulna and the distal interphalangeal joints of the phalanges. This procedure is indicated by symptoms such as thenar wasting and a positive Tinel’s test. It is important to note that the cubital retinaculum, Osborne’s ligament, palmar aponeurosis, and pisometacarpal ligament are not involved in the treatment of carpal tunnel syndrome.

Carpal tunnel syndrome is a condition that occurs when the median nerve in the carpal tunnel is compressed. This can cause pain and pins and needles sensations in the thumb, index, and middle fingers. In some cases, the symptoms may even travel up the arm. Patients may shake their hand to alleviate the discomfort, especially at night. During an examination, weakness in thumb abduction and wasting of the thenar eminence may be observed. Tapping on the affected area may also cause paraesthesia, and flexing the wrist can trigger symptoms.

There are several potential causes of carpal tunnel syndrome, including idiopathic factors, pregnancy, oedema, lunate fractures, and rheumatoid arthritis. Electrophysiology tests may reveal prolongation of the action potential in both motor and sensory nerves. Treatment options may include a six-week trial of conservative measures such as wrist splints at night or corticosteroid injections. If symptoms persist or are severe, surgical decompression may be necessary, which involves dividing the flexor retinaculum.

The drawer test is used to check for cruciate ligament rupture in the knee. The examiner flexes the hip and knee, holds the tibia, and attempts to pull it forward or backward. Excessive displacement indicates a rupture of the anterior or posterior cruciate ligament.

Knee Injuries and Common Causes

Knee injuries can be caused by a variety of factors, including twisting injuries, dashboard injuries, skiing accidents, and lateral blows to the knee. One common knee injury is the unhappy triad, which involves damage to the anterior cruciate ligament, medial collateral ligament, and meniscus. While the medial meniscus is classically associated with this injury, recent evidence suggests that the lateral meniscus is actually more commonly affected.

When the anterior cruciate ligament is damaged, it may be the result of twisting injuries. Tests such as the anterior drawer test and Lachman test may be positive if this ligament is damaged. On the other hand, dashboard injuries may cause damage to the posterior cruciate ligament. Damage to the medial collateral ligament is often caused by skiing accidents or valgus stress, and can result in abnormal passive abduction of the knee. Isolated injury to the lateral collateral ligament is uncommon.

Finally, damage to the menisci can also occur from twisting injuries. Common symptoms of meniscus damage include locking and giving way. Overall, understanding the common causes and symptoms of knee injuries can help individuals seek appropriate treatment and prevent further damage.

Systemic lupus erythematosus (SLE) is a connective tissue disorder that is more common in females and typically arises between the ages of 20 and 40. SLE can cause a range of symptoms, including a malar facial rash, arthritis, pericarditis, pleuritis, kidney disease, and neurological and psychiatric symptoms. SLE is thought to occur due to autoimmune attack against intracellular substances, such as double stranded DNA, ribonucleoproteins, histones, and phospholipids. SLE patients may release greater levels of intracellular substances due to low levels of complement factor 4 (C4), which prevents their clearance by macrophages. Anti-double stranded DNA antibodies are a specific marker of SLE, but their absence does not rule out the condition. Antibodies against citrullinated proteins are uncommon in SLE and are more commonly seen in rheumatoid arthritis. Anticentromere antibodies are rarely produced in SLE patients and are usually detected in patients with CREST syndrome. The body has high tolerance to its own cell surface proteins, including Class 1 Major Histocompatibility Complexes (MHCs), which present foreign antigens on the surfaces of cells to natural killer cells, T- and B-lymphocytes.

Understanding Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disease that is much more common in females, with a ratio of 9:1 compared to males. It is also more prevalent in Afro-Caribbeans and Asian communities. The onset of SLE usually occurs between the ages of 20-40 years, and its incidence has risen substantially over the past 50 years. SLE is considered a type 3 hypersensitivity reaction and is associated with HLA B8, DR2, and DR3.

The pathophysiology of SLE is characterized by immune system dysregulation, leading to immune complex formation. These immune complexes can deposit in any organ, including the skin, joints, kidneys, and brain. It is important to note that the incidence of SLE in black Africans is much lower than in black Americans, and the reasons for this are unclear.

In summary, SLE is a complex autoimmune disease that affects multiple organs and is more common in females and certain ethnic groups. Understanding the pathophysiology of SLE is crucial in developing effective treatments and improving patient outcomes.

The Gell and Coombs classification divides hypersensitivity reactions into four types. Type 1 is immediate and IgE mediated, type 2 is mediated by IgG and IgM causing cell death, type 3 is mediated by immune complexes, and type 4 is delayed and mediated by T lymphocytes causing contact dermatitis. Examples of each type include allergic rhinitis, Goodpasture syndrome, and rheumatoid arthritis. Nickel is a common cause of contact dermatitis.

Understanding Contact Dermatitis

Contact dermatitis is a skin condition that can be caused by two main types of reactions. The first type is irritant contact dermatitis, which is a non-allergic reaction that occurs due to exposure to weak acids or alkalis, such as detergents. This type of dermatitis is commonly seen on the hands and is characterized by erythema, but crusting and vesicles are rare.

The second type of contact dermatitis is allergic contact dermatitis, which is a type IV hypersensitivity reaction. This type of dermatitis is uncommon and is often seen on the head following hair dyes. It presents as an acute weeping eczema that predominantly affects the margins of the hairline rather than the hairy scalp itself. Topical treatment with a potent steroid is indicated for this type of dermatitis.

Cement is a frequent cause of contact dermatitis. The alkaline nature of cement may cause an irritant contact dermatitis, while the dichromates in cement can also cause an allergic contact dermatitis. It is important to understand the different types of contact dermatitis and their causes to effectively manage and treat this condition.

Rickets is a condition where the growth plate in the wrist joints widens due to an excess of non-mineralized osteoid. This is caused by a deficiency in vitamin D or calcium, which is usually due to poor dietary intake. Calcium is necessary for the mineralization of osteoid and the formation of mature bone tissue. When this process is disrupted, rickets can occur.

Monoclonal antibodies used to treat osteoporosis target RANKL, an enzyme that activates osteoclasts and promotes bone resorption. However, RANKL is not the cause of rickets.

Excessive mineralized osteoid is not the cause of rickets. Instead, rickets is caused by inadequate calcium for mineralization, leading to a buildup of non-mineralized osteoid.

While excessive osteoclast activity can cause diseases like osteoporosis and Paget’s disease, it is not the cause of rickets. Similarly, a deficiency of osteoclast activity can result in osteopetrosis, but not rickets.

Understanding Rickets

Rickets is a condition that occurs when bones in developing and growing bodies are inadequately mineralized, resulting in soft and easily deformed bones. This condition is usually caused by a deficiency in vitamin D. In adults, a similar condition is called osteomalacia.

There are several factors that can predispose individuals to rickets, including a dietary deficiency of calcium, prolonged breastfeeding, unsupplemented cow’s milk formula, and a lack of sunlight.

Symptoms of rickets include aching bones and joints, lower limb abnormalities such as bow legs or knock knees, swelling at the costochondral junction (known as a rickety rosary), kyphoscoliosis, craniotabes (soft skull bones in early life), and Harrison’s sulcus.

To diagnose rickets, doctors may check for low vitamin D levels, reduced serum calcium, and raised alkaline phosphatase. Treatment typically involves oral vitamin D supplementation.

Overall, understanding rickets and its causes can help individuals take steps to prevent this condition and ensure proper bone development and growth.

When joint aspiration is performed in cases of gout, the presence of needle-shaped monosodium urate crystals that are negatively birefringent can be observed under polarised light. The acute manifestation of gout often involves the first metatarsophalangeal joint, which is commonly referred to as podagra. Gout is caused by elevated levels of uric acid, which results in the accumulation of monosodium urate crystals in and around the joints. Pseudogout, a similar condition, is caused by the deposition of calcium pyrophosphate. In rheumatoid arthritis, a collection of fibrous tissue known as a pannus may be observed within affected joints, while osteoarthritis may present with bony projections called osteophytes. A diet that is high in purines, such as red meat, liver, and beer, may increase the likelihood of developing gout.

Understanding Gout: Symptoms and Diagnosis

Gout is a type of arthritis that causes inflammation and pain in the joints. Patients experience episodes of intense pain that can last for several days, followed by periods of no symptoms. The acute episodes usually reach their peak within 12 hours and can affect various joints, with the first metatarsophalangeal joint being the most commonly affected. Swelling and redness are also common symptoms of gout.

If left untreated, repeated acute episodes of gout can lead to joint damage and chronic joint problems. To diagnose gout, doctors may perform synovial fluid analysis to look for needle-shaped, negatively birefringent monosodium urate crystals under polarised light. Uric acid levels may also be checked once the acute episode has subsided, as they can be high, normal, or low during the attack.

Radiological features of gout include joint effusion, well-defined punched-out erosions with sclerotic margins, and eccentric erosions. Unlike rheumatoid arthritis, gout does not cause periarticular osteopenia. Soft tissue tophi may also be visible.

Saturday night syndrome is a condition where the brachial plexus is compressed due to sleeping with the arm over the back of a chair. This can result in a radial nerve palsy, commonly known as wrist drop, where the patient is unable to extend their wrist and it hangs flaccidly.

Upper limb anatomy is a common topic in examinations, and it is important to know certain facts about the nerves and muscles involved. The musculocutaneous nerve is responsible for elbow flexion and supination, and typically only injured as part of a brachial plexus injury. The axillary nerve controls shoulder abduction and can be damaged in cases of humeral neck fracture or dislocation, resulting in a flattened deltoid. The radial nerve is responsible for extension in the forearm, wrist, fingers, and thumb, and can be damaged in cases of humeral midshaft fracture, resulting in wrist drop. The median nerve controls the LOAF muscles and can be damaged in cases of carpal tunnel syndrome or elbow injury. The ulnar nerve controls wrist flexion and can be damaged in cases of medial epicondyle fracture, resulting in a claw hand. The long thoracic nerve controls the serratus anterior and can be damaged during sports or as a complication of mastectomy, resulting in a winged scapula. The brachial plexus can also be damaged, resulting in Erb-Duchenne palsy or Klumpke injury, which can cause the arm to hang by the side and be internally rotated or associated with Horner’s syndrome, respectively.

The radial nerve supplies all the extensor muscles in the arm, and a recent humerus fracture in this patient may have caused damage to this nerve. Midshaft humeral fractures can put the radial nerve at risk as it travels down the arm in the radial groove on the surface of the humerus.

In contrast, the axillary nerve is most commonly damaged in humeral head dislocations or fractures of the humeral neck, resulting in weakened shoulder abduction or reduced sensation in the inferior region of the deltoid muscle.

The median nerve is typically affected at the wrist and is commonly injured in carpal tunnel syndrome. Symptoms of median nerve damage include weakened pronation (if injured at the elbow), paralysis of the thenar muscles (if injured at the wrist), or loss of sensation over the palmar aspect of the lateral 3½ fingers.

Damage to the musculocutaneous nerve is rare and usually occurs as part of a larger injury to the brachial plexus. Symptoms of musculocutaneous nerve damage include weakened elbow flexion or loss of sensation to the lateral part of the forearm.

Finally, a medial epicondyle fracture can damage the ulnar nerve, resulting in weakness of the majority of the intrinsic hand muscles or loss of sensation to the medial 1½ fingers.

Upper limb anatomy is a common topic in examinations, and it is important to know certain facts about the nerves and muscles involved. The musculocutaneous nerve is responsible for elbow flexion and supination, and typically only injured as part of a brachial plexus injury. The axillary nerve controls shoulder abduction and can be damaged in cases of humeral neck fracture or dislocation, resulting in a flattened deltoid. The radial nerve is responsible for extension in the forearm, wrist, fingers, and thumb, and can be damaged in cases of humeral midshaft fracture, resulting in wrist drop. The median nerve controls the LOAF muscles and can be damaged in cases of carpal tunnel syndrome or elbow injury. The ulnar nerve controls wrist flexion and can be damaged in cases of medial epicondyle fracture, resulting in a claw hand. The long thoracic nerve controls the serratus anterior and can be damaged during sports or as a complication of mastectomy, resulting in a winged scapula. The brachial plexus can also be damaged, resulting in Erb-Duchenne palsy or Klumpke injury, which can cause the arm to hang by the side and be internally rotated or associated with Horner’s syndrome, respectively.

The most frequently sprained ligament in ankle inversion injuries is the anterior talofibular ligament, which runs from the talus to the fibula and restricts inversion in plantar flexion. The calcaneonavicular ligament, located between the calcaneus and navicular bones, stabilizes the medial longitudinal arch and is not involved in resisting inversion or eversion, making it unlikely to be injured. The deltoid ligament, found on the medial side of the ankle, resists eversion and is therefore not typically affected in inversion injuries. The interosseous ligament, located between the tibia and fibula above the ankle joint, is only impacted if there is trauma to the lower leg. The Lisfranc ligament, which connects the second metatarsal to the medial cuneiform, is more commonly disrupted by direct blows or axial loads on a plantarflexed foot with rotation, whereas a simple sprain to the anterior talofibular ligament is more common in inversion injuries.

Ankle Sprains: Types, Presentation, Investigation, and Treatment

Ankle sprains occur when ligaments in the ankle are stretched or torn. The ankle joint is composed of the distal tibia and fibula and the superior aspect of the talus, which form a mortise secured by ligamentous structures. Low ankle sprains involve the lateral collateral ligaments, with the anterior inferior tibiofibular ligament being the most commonly injured. Inversion injury is the most common mechanism, causing pain, swelling, tenderness, and sometimes bruising. Low ankle sprains are classified into three grades based on the extent of ligament disruption, bruising and swelling, and pain on weight-bearing. Radiographs should be done to rule out associated fractures, and MRI may be useful for evaluating perineal tendons. Treatment for low ankle sprains involves rest, ice, compression, and elevation, with occasional use of a removable orthosis, cast, or crutches. Surgical intervention is rare.

High ankle sprains involve the syndesmosis, which is rare and severe. The mechanism of injury is usually external rotation of the foot, causing the talus to push the fibula laterally. Patients experience more pain when weight-bearing than with low ankle sprains. Radiographs may show widening of the tibiofibular joint or ankle mortise, and MRI may be necessary for high suspicion of syndesmotic injury. Treatment for high ankle sprains involves non-weight-bearing orthosis or cast until pain subsides, or operative fixation if there is diastasis or failed non-operative management.

Isolated injuries to the deltoid ligament are rare and frequently associated with a fracture, such as Maisonneuve fracture of the proximal fibula. Treatment for deltoid ligament injuries is similar to that for low ankle sprains, provided the ankle mortise is anatomically reduced. If not, reduction and fixation may be necessary.

Pemphigus vulgaris is characterized by the presence of antibodies against desmoglein 3, while Grave’s disease is associated with antibodies against TSH receptors. Cardiac myopathy is linked to antibodies against desmoglein 2, while pemphigus foliaceus is associated with antibodies against desmoglein 1. Hashimoto’s hypothyroidism is characterized by the presence of antibodies against thyroid peroxidase.

Pemphigus vulgaris is an autoimmune condition that occurs when the body’s immune system attacks desmoglein 3, a type of cell adhesion molecule found in epithelial cells. This disease is more prevalent in the Ashkenazi Jewish population. The most common symptom is mucosal ulceration, which can be the first sign of the disease. Oral involvement is seen in 50-70% of patients. Skin blistering is also a common symptom, with easily ruptured vesicles and bullae. These lesions are typically painful but not itchy and may appear months after the initial mucosal symptoms. Nikolsky’s sign is a characteristic feature of pemphigus vulgaris, where bullae spread following the application of horizontal, tangential pressure to the skin. Biopsy results often show acantholysis.

The first-line treatment for pemphigus vulgaris is steroids, which help to reduce inflammation and suppress the immune system. Immunosuppressants may also be used to manage the disease.

The patella, which is the largest sesamoid bone in the body, shares an articular space with the femur and tibia. Sesamoid bones are embedded in tendons and often pass over joints to protect the tendon from damage.

Long bones, such as the femur, humerus, tibia, and fibula, have a body that is longer than it is wide.

Short bones, like the carpals, are as wide as they are long.

Flat bones are plate-like structures that serve to protect vital organs.

Irregular bones, such as the vertebrae and mandible, do not fit into any of the other categories.

Knee Problems in Children and Young Adults

Knee problems are common in children and young adults, and can be caused by a variety of conditions. Chondromalacia patellae is a condition that affects teenage girls and is characterized by softening of the cartilage of the patella. This can cause anterior knee pain when walking up and down stairs or rising from prolonged sitting. However, it usually responds well to physiotherapy.

Osgood-Schlatter disease, also known as tibial apophysitis, is often seen in sporty teenagers. It causes pain, tenderness, and swelling over the tibial tubercle. Osteochondritis dissecans can cause pain after exercise, as well as intermittent swelling and locking. Patellar subluxation can cause medial knee pain due to lateral subluxation of the patella, and the knee may give way. Patellar tendonitis is more common in athletic teenage boys and causes chronic anterior knee pain that worsens after running. It is tender below the patella on examination.

It is important to note that referred pain may come from hip problems such as slipped upper femoral epiphysis. Understanding the key features of these common knee problems can help with early diagnosis and appropriate treatment.

IgM antibody against IgG is known as rheumatoid factor.

Rheumatoid arthritis is a condition that requires initial investigations to determine the presence of antibodies. One such antibody is rheumatoid factor (RF), which is usually an IgM antibody that reacts with the patient’s own IgG. The Rose-Waaler test or latex agglutination test can detect RF, with the former being more specific. RF is positive in 70-80% of patients with rheumatoid arthritis, and high levels are associated with severe progressive disease. However, it is not a marker of disease activity. Other conditions that may have a positive RF include Felty’s syndrome, Sjogren’s syndrome, infective endocarditis, SLE, systemic sclerosis, and the general population. Anti-cyclic citrullinated peptide antibody is another antibody that may be detectable up to 10 years before the development of rheumatoid arthritis. It has a sensitivity similar to RF but a much higher specificity of 90-95%. NICE recommends testing for anti-CCP antibodies in patients with suspected rheumatoid arthritis who are RF negative. Additionally, x-rays of the hands and feet are recommended for all patients with suspected rheumatoid arthritis.

Fractures of the clavicle typically occur in the medial third, with the lateral aspect being displaced inferiorly by the weight of the arm and medially by the pull of the pectoralis major muscle. Meanwhile, the medial aspect of the fracture is usually displaced superiorly due to the pull of the sternocleidomastoid muscle.

Anatomy of the Clavicle

The clavicle is a bone that runs from the sternum to the acromion and plays a crucial role in preventing the shoulder from falling forwards and downwards. Its inferior surface is marked by ligaments at each end, including the trapezoid line and conoid tubercle, which provide attachment to the coracoclavicular ligament. The costoclavicular ligament attaches to the irregular surface on the medial part of the inferior surface, while the subclavius muscle attaches to the intermediate portion’s groove.

The superior part of the clavicle medial end has a raised surface that gives attachment to the clavicular head of sternocleidomastoid, while the posterior surface attaches to the sternohyoid. On the lateral end, there is an oval articular facet for the acromion, and a disk lies between the clavicle and acromion. The joint’s capsule attaches to the ridge on the margin of the facet.

In summary, the clavicle is a vital bone that helps stabilize the shoulder joint and provides attachment points for various ligaments and muscles. Its anatomy is marked by distinct features that allow for proper function and movement.

The primary role of the Biceps Brachii muscle is to facilitate supination and elbow flexion. It is particularly effective in supination when the elbow is flexed, such as when using a screwdriver. The muscles located in the posterior compartment of the forearm are responsible for wrist flexion, while the triceps are responsible for elbow extension and the deltoid is mostly responsible for shoulder abduction.

Upper limb anatomy is a common topic in examinations, and it is important to know certain facts about the nerves and muscles involved. The musculocutaneous nerve is responsible for elbow flexion and supination, and typically only injured as part of a brachial plexus injury. The axillary nerve controls shoulder abduction and can be damaged in cases of humeral neck fracture or dislocation, resulting in a flattened deltoid. The radial nerve is responsible for extension in the forearm, wrist, fingers, and thumb, and can be damaged in cases of humeral midshaft fracture, resulting in wrist drop. The median nerve controls the LOAF muscles and can be damaged in cases of carpal tunnel syndrome or elbow injury. The ulnar nerve controls wrist flexion and can be damaged in cases of medial epicondyle fracture, resulting in a claw hand. The long thoracic nerve controls the serratus anterior and can be damaged during sports or as a complication of mastectomy, resulting in a winged scapula. The brachial plexus can also be damaged, resulting in Erb-Duchenne palsy or Klumpke injury, which can cause the arm to hang by the side and be internally rotated or associated with Horner’s syndrome, respectively.

The adductor canal’s distal boundary is demarcated by a foramen located within the adductor magnus. The vessel traverses this area to reach the popliteal fossa.

The Adductor Canal: Anatomy and Contents

The adductor canal, also known as Hunter’s or the subsartorial canal, is a structure located in the middle third of the thigh, immediately distal to the apex of the femoral triangle. It is bordered laterally by the vastus medialis muscle and posteriorly by the adductor longus and adductor magnus muscles. The roof of the canal is formed by the sartorius muscle. The canal terminates at the adductor hiatus.

The adductor canal contains three important structures: the saphenous nerve, the superficial femoral artery, and the superficial femoral vein. The saphenous nerve is a sensory nerve that supplies the skin of the medial leg and foot. The superficial femoral artery is a major artery that supplies blood to the lower limb. The superficial femoral vein is a large vein that drains blood from the lower limb.

In order to expose the contents of the adductor canal, the sartorius muscle must be removed. Understanding the anatomy and contents of the adductor canal is important for medical professionals who perform procedures in this area, such as nerve blocks or vascular surgeries.

The anatomical snuffbox is situated above the scaphoid bone. The radial nerve’s cutaneous branch is located closer to the surface and closer to the center.

The Anatomical Snuffbox: A Triangle on the Wrist

The anatomical snuffbox is a triangular depression located on the lateral aspect of the wrist. It is bordered by tendons of the extensor pollicis longus, extensor pollicis brevis, and abductor pollicis longus muscles, as well as the styloid process of the radius. The floor of the snuffbox is formed by the trapezium and scaphoid bones. The apex of the triangle is located distally, while the posterior border is formed by the tendon of the extensor pollicis longus. The radial artery runs through the snuffbox, making it an important landmark for medical professionals.

In summary, the anatomical snuffbox is a small triangular area on the wrist that is bordered by tendons and bones. It is an important landmark for medical professionals due to the presence of the radial artery.

The cuboid bone is situated on the outer side of the foot, positioned between the heel bone at the back and the fourth and fifth toe bones towards the front.

The foot has two arches: the longitudinal arch and the transverse arch. The longitudinal arch is higher on the medial side and is supported by the posterior pillar of the calcaneum and the anterior pillar composed of the navicular bone, three cuneiforms, and the medial three metatarsal bones. The transverse arch is located on the anterior part of the tarsus and the posterior part of the metatarsus. The foot has several intertarsal joints, including the sub talar joint, talocalcaneonavicular joint, calcaneocuboid joint, transverse tarsal joint, cuneonavicular joint, intercuneiform joints, and cuneocuboid joint. The foot also has various ligaments, including those of the ankle joint and foot. The foot is innervated by the lateral plantar nerve and medial plantar nerve, and it receives blood supply from the plantar arteries and dorsalis pedis artery. The foot has several muscles, including the abductor hallucis, flexor digitorum brevis, abductor digit minimi, flexor hallucis brevis, adductor hallucis, and extensor digitorum brevis.

The aortic arch can be located at the Angle of Louis (Manubriosternal angle) on the surface. The oesophagus is situated at the back and is less susceptible to damage.

The sternal angle is a significant anatomical landmark located at the level of the upper sternum and manubrium. It is characterized by several structures, including the upper part of the manubrium, left brachiocephalic vein, brachiocephalic artery, left common carotid, left subclavian artery, lower part of the manubrium, and costal cartilages of the 2nd ribs. Additionally, the sternal angle marks the transition point between the superior and inferior mediastinum, and is also associated with the arch of the aorta, tracheal bifurcation, union of the azygos vein and superior vena cava, and the crossing of the thoracic duct to the midline. Overall, the sternal angle is a crucial anatomical structure that serves as a reference point for various medical procedures and diagnoses.

The deep peroneal nerve is responsible for supplying the muscles in the anterior compartment of the lower leg. The superficial peroneal nerve, on the other hand, innervates the muscles in the lateral compartment of the lower leg, while the tibial nerve is responsible for innervating the muscles in the posterior compartment of the lower leg. Lastly, the lateral cutaneous nerve is responsible for innervating the skin in the lower leg.

Fascial Compartments of the Leg

The leg is divided into compartments by fascial septae, which are thin layers of connective tissue. In the thigh, there are three compartments: the anterior, medial, and posterior compartments. The anterior compartment contains the femoral nerve and artery, as well as the quadriceps femoris muscle group. The medial compartment contains the obturator nerve and artery, as well as the adductor muscles and gracilis muscle. The posterior compartment contains the sciatic nerve and branches of the profunda femoris artery, as well as the hamstrings muscle group.

In the lower leg, there are four compartments: the anterior, posterior (divided into deep and superficial compartments), lateral, and deep posterior compartments. The anterior compartment contains the deep peroneal nerve and anterior tibial artery, as well as the tibialis anterior, extensor digitorum longus, extensor hallucis longus, and peroneus tertius muscles. The posterior compartment contains the tibial nerve and posterior tibial artery, as well as the deep and superficial muscles. The lateral compartment contains the superficial peroneal nerve and peroneal artery, as well as the peroneus longus and brevis muscles. The deep posterior compartment contains the tibial nerve and posterior tibial artery, as well as the flexor hallucis longus, flexor digitorum longus, tibialis posterior, and popliteus muscles.

Venous ulcers typically develop in the gaiter region, specifically around the medial malleolus. The ankle-brachial pressure index and venous duplex ultrasound are diagnostic tools used to investigate ulcers, not treat them. The primary conservative treatment for venous ulcers is four-layer compression bandaging. If conservative measures fail, surgical debridgement may be considered. There is limited evidence supporting the use of intermittent pneumatic compression devices for venous ulcers.

Venous ulceration is a type of ulcer that is commonly found above the medial malleolus. To determine the cause of non-healing ulcers, it is important to conduct an ankle-brachial pressure index (ABPI) test. A normal ABPI value is between 0.9 to 1.2, while values below 0.9 indicate arterial disease. However, values above 1.3 may also indicate arterial disease due to arterial calcification, especially in diabetic patients.

The most effective treatment for venous ulceration is compression bandaging, specifically four-layer bandaging. Oral pentoxifylline, a peripheral vasodilator, can also improve the healing rate of venous ulcers. While there is some evidence supporting the use of flavonoids, there is little evidence to suggest the benefit of hydrocolloid dressings, topical growth factors, ultrasound therapy, and intermittent pneumatic compression.

The common peroneal component of the sciatic nerve innervates the short head of biceps femoris, which may be absent at times. On the other hand, the tibial division of the sciatic nerve innervates the long head.

The Biceps Femoris Muscle

The biceps femoris is a muscle located in the posterior upper thigh and is part of the hamstring group of muscles. It consists of two heads: the long head and the short head. The long head originates from the ischial tuberosity and inserts into the fibular head. Its actions include knee flexion, lateral rotation of the tibia, and extension of the hip. It is innervated by the tibial division of the sciatic nerve and supplied by the profunda femoris artery, inferior gluteal artery, and the superior muscular branches of the popliteal artery.

On the other hand, the short head originates from the lateral lip of the linea aspera and the lateral supracondylar ridge of the femur. It also inserts into the fibular head and is responsible for knee flexion and lateral rotation of the tibia. It is innervated by the common peroneal division of the sciatic nerve and supplied by the same arteries as the long head.

Understanding the anatomy and function of the biceps femoris muscle is important in the diagnosis and treatment of injuries and conditions affecting the posterior thigh.

The primary neurovascular structure that can be affected by a scaphoid fracture is the dorsal carpal branch of the radial artery. This artery is responsible for supplying blood to the scaphoid bone, and a fracture can lead to a high risk of avascular necrosis in the proximal pole of the bone. Symptoms of a scaphoid fracture include tenderness in the anatomical snuffbox, pain when compressing the thumb longitudinally, and a loss of grip strength. While an X-ray may not provide a conclusive diagnosis, further imaging studies can confirm the presence of an occult fracture.

The other answer choices are incorrect. The common digital arteries originate from the superficial palmar arch and supply the fingers. The deep palmar arch primarily supplies the thumb and index finger. The proper digital arteries arise from the common digital arteries and supply the fingers.

A scaphoid fracture is a type of wrist fracture that usually occurs when a person falls onto an outstretched hand or during contact sports. It is important to identify scaphoid fractures as they can lead to avascular necrosis due to the unusual blood supply of the scaphoid bone. Patients with scaphoid fractures typically experience pain along the radial aspect of the wrist and loss of grip or pinch strength. Clinical examination involves checking for tenderness over the anatomical snuffbox, wrist joint effusion, pain on telescoping of the thumb, tenderness of the scaphoid tubercle, and pain on ulnar deviation of the wrist. Plain film radiographs and scaphoid views are used to diagnose scaphoid fractures, but MRI is considered the definitive investigation. Initial management involves immobilization with a splint or backslab and referral to orthopaedics. Orthopaedic management depends on the type of fracture, with undisplaced fractures typically treated with a cast and displaced fractures requiring surgical fixation. Complications of scaphoid fractures include non-union and avascular necrosis.

The femoral nerve is responsible for loss of knee extension and sensory loss to the anterior and medial aspect of the thigh following a stab injury. The muscles innervated by the femoral nerve are responsible for hip flexion and knee extension, while the nerve is responsible for sensation over the anterior thigh. Injury to the inferior gluteal nerve would result in loss of hip extension, while injury to the obturator nerve would result in a loss of sensation to the medial thigh and impaired hip adduction. Although the quadriceps tendon is vital to knee extension, it would not explain the sensory deficit and the location of the injury.

Lower limb anatomy is an important topic that often appears in examinations. One aspect of this topic is the nerves that control motor and sensory functions in the lower limb. The femoral nerve controls knee extension and thigh flexion, and provides sensation to the anterior and medial aspect of the thigh and lower leg. It is commonly injured in cases of hip and pelvic fractures, as well as stab or gunshot wounds. The obturator nerve controls thigh adduction and provides sensation to the medial thigh. It can be injured in cases of anterior hip dislocation. The lateral cutaneous nerve of the thigh provides sensory function to the lateral and posterior surfaces of the thigh, and can be compressed near the ASIS, resulting in a condition called meralgia paraesthetica. The tibial nerve controls foot plantarflexion and inversion, and provides sensation to the sole of the foot. It is not commonly injured as it is deep and well protected, but can be affected by popliteral lacerations or posterior knee dislocation. The common peroneal nerve controls foot dorsiflexion and eversion, and can be injured at the neck of the fibula, resulting in foot drop. The superior gluteal nerve controls hip abduction and can be injured in cases of misplaced intramuscular injection, hip surgery, pelvic fracture, or posterior hip dislocation. Injury to this nerve can result in a positive Trendelenburg sign. The inferior gluteal nerve controls hip extension and lateral rotation, and is generally injured in association with the sciatic nerve. Injury to this nerve can result in difficulty rising from a seated position, as well as difficulty jumping or climbing stairs.

The patient is likely to have suffered damage to their common peroneal nerve, resulting in foot drop, following a fibular neck fracture. This is a common occurrence in such cases.

It is important to note that damage to the lateral cutaneous nerve of the thigh, obturator nerve, or pudendal nerve is unlikely to cause foot drop. These nerves are associated with different symptoms and conditions.

Lower limb anatomy is an important topic that often appears in examinations. One aspect of this topic is the nerves that control motor and sensory functions in the lower limb. The femoral nerve controls knee extension and thigh flexion, and provides sensation to the anterior and medial aspect of the thigh and lower leg. It is commonly injured in cases of hip and pelvic fractures, as well as stab or gunshot wounds. The obturator nerve controls thigh adduction and provides sensation to the medial thigh. It can be injured in cases of anterior hip dislocation. The lateral cutaneous nerve of the thigh provides sensory function to the lateral and posterior surfaces of the thigh, and can be compressed near the ASIS, resulting in a condition called meralgia paraesthetica. The tibial nerve controls foot plantarflexion and inversion, and provides sensation to the sole of the foot. It is not commonly injured as it is deep and well protected, but can be affected by popliteral lacerations or posterior knee dislocation. The common peroneal nerve controls foot dorsiflexion and eversion, and can be injured at the neck of the fibula, resulting in foot drop. The superior gluteal nerve controls hip abduction and can be injured in cases of misplaced intramuscular injection, hip surgery, pelvic fracture, or posterior hip dislocation. Injury to this nerve can result in a positive Trendelenburg sign. The inferior gluteal nerve controls hip extension and lateral rotation, and is generally injured in association with the sciatic nerve. Injury to this nerve can result in difficulty rising from a seated position, as well as difficulty jumping or climbing stairs.

The patient’s shortened and externally rotated right leg indicated a fracture of the neck of the femur, which was determined to be a fragility fracture due to osteoporosis. This condition is a common cause of fragility fractures in postmenopausal women, as decreased estrogen levels lead to increased bone resorption and decreased bone mass. Other bone-related conditions, such as osteopetrosis, osteomalacia, Paget disease of the bone, and osteosarcoma, have different underlying causes and presentations.

Osteoporosis is a condition that is more prevalent in women and increases with age. However, there are many other risk factors and secondary causes of osteoporosis. Some of the most significant risk factors include a history of glucocorticoid use, rheumatoid arthritis, alcohol excess, parental hip fracture history, low body mass index, and current smoking. Other risk factors include a sedentary lifestyle, premature menopause, certain ethnicities, endocrine disorders, gastrointestinal disorders, chronic kidney disease, and certain genetic disorders. Additionally, certain medications such as SSRIs, antiepileptics, and proton pump inhibitors may worsen osteoporosis.

If a patient is diagnosed with osteoporosis or has a fragility fracture, further investigations may be necessary to identify the cause of osteoporosis and assess the risk of subsequent fractures. Recommended investigations include a history and physical examination, blood tests such as a full blood count, urea and electrolytes, liver function tests, bone profile, CRP, and thyroid function tests. Other procedures may include bone densitometry, lateral radiographs, protein immunoelectrophoresis, and urinary Bence-Jones proteins. Additionally, markers of bone turnover and urinary calcium excretion may be assessed. By identifying the cause of osteoporosis and contributory factors, healthcare providers can select the most appropriate form of treatment.