Suture Materials

Sutures are essential in surgical procedures for wound closure and tissue approximation. Various types of sutures are available, each with unique properties, advantages, and applications. Below is a summary of some commonly used suture materials, including chromic catgut, polypropylene, polyglycolic acid, and polyamide (nylon).

1. Chromic Catgut

• Description:

  • Chromic catgut is a natural absorbable suture made from collagen derived from the submucosa of sheep intestines or the serosa of beef cattle intestines. It is over 99% pure collagen.

• Absorption Process:

  • The absorption of chromic catgut occurs through enzymatic digestion by proteolytic enzymes, which are derived from lysozymes contained within polymorphonuclear leukocytes (polymorphs) and macrophages.

• Absorption Rate:

  • The absorption rate depends on the size of the suture and whether it is plain or chromicized. Typically, absorption is completed within 60-120 days.

• Applications:

  • Commonly used in soft tissue approximation and ligation, particularly in areas where a temporary support is needed.

2. Polypropylene (Proline)

• Description:

  • Polypropylene is a synthetic monofilament suture made from a purified and dyed polymer.

• Properties:

  • It has an extremely high tensile strength, which it retains indefinitely after implantation. Polypropylene is non-biodegradable, meaning it does not break down in the body.

• Applications:

  • Ideal for use in situations where long-term support is required, such as in vascular surgery, hernia repairs, and other procedures where permanent sutures are beneficial.

3. Polyglycolic Acid

• Description:

  • Polyglycolic acid is a synthetic absorbable suture formed by linking glycolic acid monomers to create a polymer.

• Properties:

  • It is known for its predictable absorption rate and is commonly used in various surgical applications.

• Applications:

  • Frequently used in soft tissue approximation, including in gastrointestinal and gynecological surgeries, where absorbable sutures are preferred.

4. Polyamide (Nylon)

• Description:

  • Polyamide, commonly known as nylon, is a synthetic non-absorbable suture that is chemically extruded and generally available in monofilament form.

• Properties:

  • Nylon sutures have a low coefficient of friction, making passage through tissue easy. They also elicit minimal tissue reaction.

• Applications:

  • Used in a variety of surgical procedures, including skin closure, where a strong, durable suture is required.

Sinus

It is a tubular track lined by granulation tissue and open at one end which is at the surface,

eg. Tuberculous Sinus

Fistula

A tubular track lined by granulation tissue and open at both ends.at least one of which communicates with a hollow viscus. it can be internal or external.

Causes

1. Inadequate drainage

• Abscess bursting at the non dependent part
• Incision at the non-dependent part.
• Narrow outer opening leading to collection of exudates in the cavity.

2. Presence of foreign body like sequestrum or slough.

3. Persistence of infection.

4. When the track is lined by epithelium

5. Specific causes, TB., Syphilis, etc.

6. Marked fibrosis of the wall with obliteration of blood vessels.

7. Poor general condition causing delayed healing.

Treatment

1. control of specific infection,

2. Thorough excision of track to open up the cavity. Removal of foreign body and scraping of the epithelium

3. Through Scrapping of the wall to expose healthy tissue

4. Wound laid open and allowed to heal from the bottom leaving no pocket,

Inflammation is the respone of the body to an irritant.

Stages of Inflammation

1. General: Temperature Raised. In severe cases bacteremia or septicemia ,rigors may occur.

2. Local: classical signs of inflammation are due to hyperemia and inflammation exudate

i) Heat:  inflammed area feels warmer than the surrounding tissues.

ii) Redness

iii) Tenderness: Due to pressure of exudate on the surrounding nerves  If the exudate is  under tension, e.g. a furuncle (boil) of the ear, pain is severe.

iv) swelling

v) Loss of function.

The termination of Inflammation

This may be by:1. Resolution 2. Suppuration 3. Ulceration 4. Ganangren s. Fibrosis

Management

i. Increase the patients resistance., Rest,  Relief of pain by analgesics,  Diet: High protein and high calorie diet with vitamins,  Antibiotics,  Prevent further contamination of wound.

Surgical measures

1. Excision: If possible as in appendicectomy.

2. Incision and drainage: If an abscess forms.

TMJ Ankylosis

Temporomandibular Joint (TMJ) ankylosis is a condition characterized by the abnormal fusion of the mandibular condyle to the temporal bone, leading to restricted jaw movement. This condition can significantly impact a patient's ability to open their mouth and perform normal functions such as eating and speaking.

Causes and Mechanisms of TMJ Ankylosis

1. Condylar Injuries:

   • Most cases of TMJ ankylosis result from condylar injuries sustained before the age of 10. The unique anatomy and physiology of the condyle in children contribute to the development of ankylosis.

2. Unique Pattern of Condylar Fractures in Children:

   • In children, the condylar cortical bone is thinner, and the condylar neck is broader. This anatomical configuration, combined with a rich subarticular vascular plexus, predisposes children to specific types of fractures.
   • Intracapsular Fractures: These fractures can lead to comminution (fragmentation) and hemarthrosis (bleeding into the joint) of the condylar head. A specific type of intracapsular fracture known as a "mushroom fracture" occurs, characterized by the comminution of the condylar head.

3. Formation of Fibrous Mass:

   • The presence of a highly osteogenic environment (one that promotes bone formation) following a fracture can lead to the organization of a fibrous mass. This mass can undergo ossification (the process of bone formation) and consolidation, ultimately resulting in ankylosis.

4. Trauma from Forceps Delivery:

   • TMJ ankylosis can also occur due to trauma sustained during forceps delivery, which may cause injury to the condylar region.

Etiology and Risk Factors

Laskin (1978) outlined several factors that may contribute to the etiology of TMJ ankylosis following trauma:

1. Age of Patient:

   • Younger patients have a significantly higher osteogenic potential and a more rapid healing response. The articular capsule in younger individuals is not as well developed, allowing for easier displacement of the condyle out of the fossa, which can damage the articular disk. Additionally, children may exhibit a greater tendency for prolonged self-imposed immobilization of the mandible after trauma.

2. Type of Fracture:

   • The condyle in children has a thinner cortex and a thicker neck, which predisposes them to a higher proportion of intracapsular comminuted fractures. In contrast, adults typically have a thinner condylar neck, which usually fractures at the neck, sparing the head of the condyle within the capsule.

3. Damage to the Articular Disk:

   • Direct contact between a comminuted condyle and the glenoid fossa, either due to a displaced or torn meniscus (articular disk), is a key factor in the development of ankylosis. This contact can lead to inflammation and subsequent bony fusion.

4. Period of Immobilization:

   • Prolonged mechanical immobilization or muscle splinting can promote orthogenesis (the formation of bone) and consolidation in an injured condyle. Total immobility between articular surfaces after a condylar injury can lead to a bony type of fusion, while some movement may result in a fibrous type of union.

Types of Brain Injury

Brain injuries can be classified into two main categories: primary and secondary injuries. Understanding these types is crucial for effective diagnosis and management.

1. Primary Brain Injury

• Definition: Primary brain injury occurs at the moment of impact. It results from the initial mechanical forces applied to the brain and can lead to immediate damage.
• Examples:
  • Contusions: Bruising of brain tissue.
  • Lacerations: Tears in brain tissue.
  • Concussions: A temporary loss of function due to trauma.
  • Diffuse axonal injury: Widespread damage to the brain's white matter.

2. Secondary Brain Injury

• Definition: Secondary brain injury occurs after the initial impact and is often preventable. It results from a cascade of physiological processes that can exacerbate the initial injury.
• Principal Causes:
  • Hypoxia: Reduced oxygen supply to the brain, which can worsen brain injury.
  • Hypotension: Low blood pressure can lead to inadequate cerebral perfusion.
  • Raised Intracranial Pressure (ICP): Increased pressure within the skull can compress brain tissue and reduce blood flow.
  • Reduced Cerebral Perfusion Pressure (CPP): Insufficient blood flow to the brain can lead to ischemia.
  • Pyrexia: Elevated body temperature can increase metabolic demands and worsen brain injury.

Glasgow Coma Scale (GCS)

The Glasgow Coma Scale is a clinical tool used to assess a patient's level of consciousness and neurological function. It consists of three components: eye opening, verbal response, and motor response.

Eye Opening (E)

• Spontaneous: 4
• To verbal command: 3
• To pain stimuli: 2
• No eye opening: 1

Verbal Response (V)

• Normal, oriented: 5
• Confused: 4
• Inappropriate words: 3
• Sounds only: 2
• No sounds: 1

Motor Response (M)

• Obeys commands: 6
• Localizes to pain: 5
• Withdrawal flexion: 4
• Abnormal flexion (decorticate): 3
• Extension (decerebrate): 2
• No motor response: 1

Scoring

• Best Possible Score: 15/15 (fully alert and oriented)
• Worst Possible Score: 3/15 (deep coma or death)
• Intubated Cases: For patients who are intubated, the verbal score is recorded as "T."
• Intubation Indication: Intubation should be performed if the GCS score is less than or equal to 8.

Additional Assessments

Pupil Examination

• Pupil Reflex: Assess size and light response.
• Uncal Herniation: In cases of mass effect on the ipsilateral side, partial third nerve dysfunction may be noted, characterized by a larger pupil with sluggish reflex.
• Hutchinson Pupil: As third nerve compromise increases, the ipsilateral pupil may become fixed and dilated.

Signs of Base of Skull Fracture

• Raccoon Eyes: Bilateral periorbital hematoma, indicating possible skull base fracture.
• Battle’s Sign: Bruising over the mastoid process, suggesting a fracture of the temporal bone.
• CSF Rhinorrhea or Otorrhea: Leakage of cerebrospinal fluid from the nose or ear, indicating a breach in the skull base.
• Hemotympanum: Blood in the tympanic cavity, often seen with ear bleeding.

Types of Head Injury

1. Extradural Hematoma (EDH)

Overview

• Demographics: Most common in young male patients.
• Association: Always associated with skull fractures.
• Injured Vessel: Middle meningeal artery.
• Common Site of Injury: Temporal bone at the pterion (the thinnest part of the skull), which overlies the middle meningeal artery.
• Location of Hematoma: Between the bone and the dura mater.

Other Common Sites

1. Frontal fossa
2. Posterior fossa
3. May occur following disruption of major dural venous sinus.

Classical Presentation

• Initial Injury: Followed by a lucid interval where the patient may only complain of a headache.
• Deterioration: After minutes to hours, rapid deterioration occurs, leading to:
  • Contralateral hemiparesis
  • Reduced consciousness level
  • Ipsilateral pupillary dilatation (due to herniation)

Imaging

• CT Scan: Shows a lentiform (lens-shaped or biconvex) hyperdense lesion between the brain and skull.

Treatment

• Surgical Intervention: Immediate surgical evacuation via craniotomy.
• Mortality Rate: Overall mortality is 18% for all cases of EDH, but only 2% for isolated EDH.

2. Acute Subdural Hematoma (ASDH)

Overview

• Location: Accumulates in the space between the dura and arachnoid.
• Injury Mechanism: Associated with cortical vessel disruption and brain laceration.
• Primary Brain Injury: Often associated with primary brain injury.

Presentation

• Consciousness: Impaired consciousness from the time of impact.

Imaging

• CT Scan: Appears hyperdense, with hematoma spreading diffusely and having a concavo-convex appearance.

Treatment

• Surgical Intervention: Evacuation via craniotomy.
• Mortality Rate: Approximately 40%.

3. Chronic Subdural Hematoma (CSDH)

Overview

• Demographics: Most common in patients on anticoagulants and antiplatelet agents.
• History: Often follows a minor head injury weeks to months prior.
• Pathology: Due to the tear of bridging veins leading to ASDH, which is clinically silent. As the hematoma breaks down, it increases in volume, causing mass effect on the underlying brain.

Clinical Features

• Symptoms may include:
  • Headache
  • Cognitive decline
  • Focal neurological deficits (FND)
  • Seizures
• Important to exclude endocrine, hypoxic, and metabolic causes in this group.

Imaging

• CT Scan Appearance:
  • Acute blood (0–10 days): Hyperdense
  • Subacute blood (10 days to 2 weeks): Isodense
  • Chronic (> 2 weeks): Hypodense

Treatment

• Surgical Intervention: Bur hole evacuation rather than craniotomy.
• Anesthesia: Elderly patients can often undergo surgery under local anesthesia, despite comorbidities.

4. Subarachnoid Hemorrhage (SAH)

Overview

• Causes: Most commonly due to aneurysms for spontaneous SAH, but trauma is the most common cause overall.
• Management: Conservative treatment is often employed for trauma cases.

5. Cerebral Contusions

Overview

• Definition: Bruising of the brain tissue due to trauma.
• Mechanism: Often occurs at the site of impact (coup) and the opposite side (contrecoup).
• Symptoms: Can range from mild confusion to severe neurological deficits depending on the extent of the injury.

Imaging

• CT Scan: May show areas of low attenuation (hypodense) or high attenuation (hyperdense) depending on the age of the contusion.

Treatment

• Management: Depends on the severity and associated injuries; may require surgical intervention if there is significant mass effect.