Awad Alsaidi محمد الشطناوي. Ahmad

Transcription

1 12 Awad Alsaidi محمد الشطناوي Ahmad

2 Clinical applications on the lower limb (injuries) 1. Common Peroneal nerve injury: *The common peroneal nerve is exposed to a high risk of injury, due to its course as it leaves the popliteal fossa and winds around the neck of the fibula to enter the peroneus longus muscle. - Motor effects: * Paralysis of theextensor group of muscles, located in the anterior compartment of the leg (Supplied by the Deep Peroneal nerve), this means the loss of Dorsiflexionof the foot. * Paralysis of the Peronei group of muscles, located in the lateral compartment of the leg (Supplied by the Superficial Peroneal nerve), this means the loss of Eversion of the foot. The Antagonistic groups of muscles; the plantar flexors and invertors take over. Leading thefoot to be plantar flexed (Foot Drop) and inverted, in a condition called Equinovarus. - Sensory effects: *There will be a loss of sensation over: Most of the dorsum of the foot, except for the lateral side, which is supplied by the Sural nerve and the medial side supplied by the Saphenous nerve. The anterio-lateral aspect of the leg.

3 2. Tibial nerve injury *Rarely injured, due to its deep and protected position* Injury of the tibial nerve results in the following clinical features: - Motor: Paralysis of all the muscles in the back of the leg and sole of the foot Calcaneovalgus : an attitude of the opposing muscles which involves the dorsiflexion of the foot at the ankle joint and eversion of the foot at the subtalar and transverse tarsal joints. - Sensory: Loss of sensation at the sole of the foot and trophic ulcers may develop later on 3. Obturator nerve injury - Common causes of injury: Penetrating wounds Anterior dislocation of the hip joint Abdominal hernias through the obturator foramen Pressure by the fetal head during parturition Clinical features of obturator nerve injury: - Motor: Paralysis of the entire group of adductor muscles, except for the hamstring part of the Adductor Magnus (innervated by the sciatic nerve). - Sensory: A minimal loss of cutaneous sensory supply over the medial aspect of the thigh.

4 Venous injuries of the lower limb The veins of the lower limb are classified into three groups: 1. Superficial veins: in the superficial fascia, below the skin. The Great saphenous vein The Small saphenous vein 2. Deep veins: venae comitantes subjected to high pressure, surrounded by muscles. 3. Perforating veins: communicating vessels that run between superficial and deep veins, largely found within the ankle region and the lower aspect of the leg. *Perforating veins contain special valves that are placed as to prevent blood flow from high pressure deep veins to superficial veins. - Varicose veins: a common condition in the superficial veins of the lower limb, caused by the incompetence of a valve in a perforating vein. Leads to the formation of a varicosed vein: has a larger than normal diameter and is elongated and tortuous.

5 Dermatomes in the lower limb - Dermatomes: regions that can be tested for sensation and are reasonably autonomous (have minimal overlap). *certain methods of testing are used to locate an injury in the spinal cord, by applying force onto a dermatome. However, the results can be ambiguous or unclear. Therefore testing fortendon reflexes is a more accurate procedure especially in unresponsive patients. We sit on S3 and we stand on S1. Testing for sensory and motor somatic functions of the spinal cord using tendon reflexes: *Particularly useful with unresponsive patients. 1. Patellar tendon reflex (knee joint) : *The knee must be flexed prior to testing for the action to be evident. - The physician taps the patellar ligament at the knee and the reflex anticipated is the extension of the knee joint. - This procedure tests for the functions of L3 and L4 at the spinal cord level. 2. Achilles tendon reflex (ankle jerk) : - Upon tapping the Achilles tendon, plantar flexion at the ankle joint is expected. - This tests for the functions of S1 and S2.

6 Fractures of the distal end of the femur - The fractured distal end of the femur is pulled backwards by the Gastrocnemius to a large extent and may damage the popliteal artery; interfering with the blood flow through the leg and foot. Popliteal Cysts - Popliteal cysts are abnormal fluid filled sacs of synovial membrane in the popliteal fossa.often the result of inflammation. - They are common in children, and are usually asymptomatic. - In adults, popliteal cysts can be large, extending as far as the mid-calf and may interfere with knee movement. *Large cysts completely abort knee flexion, smaller cysts may allow little flexion of the knee joint. Anterior compartment of the leg syndrome - Is produced by an increase in the intra-compartmental pressure which is a result of elevated tissue fluid production. - Soft tissue injury associated with bone fractures is a common cause. - Early diagnosis is crucial. - The immense fluid pressure pushes down on the nerves, mainly the deepperoneal nerve, causing a deep aching pain which is a characteristic of this syndrome. Dorsiflexion of the ankle joint severely increases the pain. - As the pressure rises, the venous return diminishes ( edema and effusion), further increasing the pressure. - In severe cases, the arterial supply (Dorsalis Pedis) is cut-off by compression; causing ischemia, also the dorsalispedis pulsation disappears.

7 - The Tibialis anterior, Extensor halluces longusand Extensor digitorum longusare all paralyzed. *Dorsiflexion is impaired. - Loss of sensation is limited to the area supplied by the deep peroneal nerve;the skin cleft between the first and second toes. Treatment: Cutting open the anterior compartment of the leg; making a longitudinal incision through the deep fascia. Thus, decompressing the leg and relieving the accumulated pressure. Hallux Valgus - A foot deformity may be caused by degenerative joint disease, but is mostly congenital. - It is characterized by a lateral deviation of the hallux. In some people, the deviation is so great; the first toe overlaps the second. In such cases, the individuals are unable to move the first toe away from the second as the sesamoid bones under the head of the first metatarsal are displaced and lie in the space between the first and second metatarsals. - A subcutaneous bursa may also form due to the constant pressure and friction against the shoe. When tender and inflamed, the bursa is called a Bunion great toe.

8 Piriformis Syndrome - The common fibular nerve may be compressed by the piriformis muscle as it passes through its fibers. Which is an abnormal situation, as the common fibular nerve usually passes below the piriformis, along with the tibial nerve. - Another case of this syndrome involves the compression of the sciatic nerve. *The piriformis syndrome results in motor and sensory loss to both the anterior and lateral compartments of the leg. With the piriformis syndrome being explained, we have completed the required clinical applications on the lower limb. - The Diaphragm: A muscle that acts as a fibro-muscular partition that separates the thoracic cavity from the abdominal cavity. Origin: the posterior surface of the sternum, the lower six ribs and two vertebrae: left and right crura plus five arcuate ligaments.right crus (arises from the upper 3 vertebrae), Left crus (from the upper 2 vertebrae). Insertion:the fibers join, forming the central tendon which lies directly below the heart. Nerve supply:thephrenic nerve (C3,C4,C5) Action: the main respiratory muscle. Arcuate ligaments (5): -Median ligament: stretches between the right and left crura. -Medial ligaments (2): arise from the body of L2 and attach to the transverse process of L1. Cross Psaos Major. -Lateral ligaments (2): arise from the transverse process of L1 and attach at the last rib. CrossQuadratus lumborum. *Clinical application* The Costovertebral angle: is an angle formed on the lateral side of the body between the vertebral column and the last rib. The kidney and pleura are subject to contact and friction in certain cases, like kidney inflammation. The pleura might also be damaged when operating on the kidney, due to their proximity,

9 - The foramina of the diaphragm:three major openings and five minor ones. *Inferior Vena Cava opening, projects to the right- at T8 *Esophageal hiatus, situated to the left - at T10 *Aortic hiatus, centrally positioned (most posterior, to evade muscle contraction) - at T12 - Structures passing along with the Aorta: *The Thoracic duct: rises from the abdomen and drains in the thorax region. *The Azygous vein: passes through the thoracic wall, from the abdomen. - Structures passing along with the Vena Cava: *Right Phrenic nerve; supplies the diaphragm. *Lymphatics - Structures passing along the esophagus: *The Vagusnerve; descends to the abdominal region. The smaller foramina of the diaphragm - Two arteries and five nerves pass through the smaller openings: *The Internal Thoracic artery: splits into two terminal branches, the epigastric(1)and musculophrenic(2)arteries. *The Left Phrenic Nerve(1) *Lower six intercostal Nerves(2): pass between rib bones and supply the abdominal wall. *The last of them being Subcostal nerves(3). *The Sympathetic trunk (chain) (4) *Splanchnic nerves (sympathetic) (5) Functions of the diaphragm: - The main respiratory muscle - Increases intra-abdominal pressure (contraction):greatly assists with urination, defecation and vomiting. - The diaphragm as athoraco-abdominal pump: it helps with lymph drainage from the visceral organs by creating a negative pressure; pulling lymph from the abdominal region upwards through the lymphatic system. As well as supporting blood flow. - A weight lifting muscle: the diaphragm pushes downwards;increasing intraabdominal pressure, supporting the vertebral column and preventing its flexion.

10 Joints of the vertebral column 1. Joints of the vertebral bodies: *Secondary cartilaginous joints (Sympheses) *IV disks connect the articulating surfaces of adjacent vertebrae: -Provide strength, support and are shock absorbent -Permit little movement between vertebrae -Degenerate with age, due to constant pressure and friction *Each IV disk consists of two parts: An inner gelatinous core (nucleus pulposus), provides elasticity. An outer fibrous part (annulus fibrosus), provides strength and support. *Joints of the vertebral bodies are stabilized by two ligaments: a. Anterior Longitudinal ligament: - A strong, broad and fibrous band - The only ligament anterior to the vertebral body b. Posterior longitudinal ligament: - A narrower, somewhat weaker ligament

11 *Clinical Application* -Vertebral Disk herniation: *Degeneration of the annulus fibrosus allows the nucleus pulposus to escape the IV disc, making nerves prone to contact with the gelatinous substance. This gives rise to manifestations that could be either Motor or Sensory in nature. *Treatment (surgical intervention): Last resort Laminectomy: Cutting through the vertebral body (posteriorly) at the lamina to reach the IV disc and remove its escaped material. *Microdiscectomy: this procedure is done by microscopically removing the fragments of herniated disc, it s minimally invasive.