Orthopedics Review PDF

Version (1) – Updated on September 2022 Review some basics ☺ Stages of bone healing: o Inciting event >> Hematoma development & inflammatory mediators release. o Inflammation phase (1-7 days): ▪ Osteoclasts are act...

Version (1) – Updated on September 2022 Review some basics ☺ Stages of bone healing: o Inciting event >> Hematoma development & inflammatory mediators release. o Inflammation phase (1-7 days): ▪ Osteoclasts are activated to remove necrotic bone & sharp bone endings. ▪ Granulation tissue forms and vessels begin to seed the injury site. o Reparative phase: ▪ Soft callus (2-3 weeks) >> periosteal reaction stimulating osteoblasts to form new bone inwards between the 2 fragments. ▪ Hard callus (3-4 months) >> intramembranous bone formation begin to ossify the distal regions while endochondrial ossification takes place centrally to produce woven bone. o Remodeling phase (may take years) >> woven bone slowly replaced by lamellar bone through remodeling. Major orthopedics emergencies: o Open (compound) fractures. o Vascular & neuronal injuries (especially of the spine). o Compartment syndrome. o Bone infections (osteomyelitis & septic arthritis). o Hip dislocation & fracture (risk of avascular necrosis). o Exsanguinating pelvic fracture (open pelvic fractures have a 50% mortality!!). General fracture complications: o Local: ▪ Neurological or vascular injury. ▪ Infections or osteomyelitis. ▪ Compartment syndrome. ▪ Fracture blisters. ▪ Mal or non-union. ▪ Avascular necrosis (especially in scaphoid or femoral neck). ▪ Post-traumatic osteoarthritis. o Systemic >> sepsis, DVT, PE, ARDS (fat embolism). @Gatetomedicine 4  Version (1) – Updated on September 2022 Types of fractures (important) Overview of fractures: o Fracture is defined as discontinuity of bone (cortex). o While discussing a fracture, we must comment on: ▪ Location >> Which bone, which 1/3rd, which part (epiphysis, diaphysis, metaphysis, growth plate). ▪ Integrity of skin >> open or closed fracture. ▪ Fracture pattern (type) >> discussed later. ▪ Alignment: Displaced >> not in anatomical alignment (distal fragment in relation to Varus >> distal segment is going towards proximal fragment). midline (genu varus = bowleg). Distrected >> fracture fragments separated by a gap. Valgus >> distal segment is going away from midline (genu valgum = knock- Impacted >> fracture fragments are compressed into each other. knees). Angulated >> direction of fracture apex is varus or valgus. Types of fractures: o Open fracture: ▪ Bone has protruded through the soft tissue & cased a break in the skin. ▪ The major fear & concern is infection (open fracture is an orthopedic emergency). ▪ Grading (Gustilo-Anderson classification) >> Depends on size of laceration, tissue loss or devitalization, & major vascular injury. ▪ Initial management: Primary & secondary survey (ABCs). Pain control (morphine, fentanyl). IV prophylactic antibiotics (cefazolin, +/- gentamicin). Tetanus coverage (Td vaccine & TIG). Lavage wound with sterile irrigation & dressing. Important investigations (X-ray, trauma labs, ECG, CXR, consent). Surgical debridement. Open reduction & fixation (upper limb usually internal). o Pathological fractures: ▪ Fractures that occur in weak bone as a result of a pathological disease. ▪ Causes: Osteoporosis (most common). Metastatic bone disease & Primary bone cancers. Multiple myeloma. Osteomalacia & rickets. Others >> osteogenesis imperfecta, scurvy, bone infections. ▪ Underlying disease must be treated. @Gatetomedicine 5  Version (1) – Updated on September 2022 o Stress fractures: ▪ Fractures that occurs in normal bones as a result of repetitive stress with March fracture is the inadequate healing time in between. fracture of the distal ▪ Typical in young adults in military training (March fracture), ballerinas, sport third of metatarsals players, hard repeated physical activity. occur due to recurrent stress ▪ Common sites >> metatarsals, calceneus, tibia. ▪ Pain is occur usually during activity. ▪ The micro-fractures may not be visible in the 1st or 2nd weeks on X-ray. However, it may be visible in directly after 2 weeks by callus formation. ▪ Management >> temporary limitation of weight bearing or toning down physical activity. March Fracture o Pediatric age group fractures: ▪ Children develops a certain types of fracture due to the collagenous nature of immature bone. ▪ It’s very important to note growth plate fractures, it may cause growth arrest. ▪ Pediatric patients are expected to have a full recovery if everything is in order. ▪ Torus fracture >> buckle fracture of one cortex (impaction injury of childhood), the lateral ends of fracture appears bulging. ▪ Greenstick fracture >> incomplete & angulated fracture of long bone. @Gatetomedicine 6 Version (1) – Updated on September 2022 Patterns of fracture: o Complete fracture >> the fracture line goes across the whole width of bone. o Transverse fracture >> fracture line perpendicular to long axis of bone. o Oblique fracture >> fracture line isn’t straight. o Spiral fracture >> rotational force to bone results in a complex S-shaped fracture around the whole bone (if found in pediatrics, suspect child abuse). o Segmental fracture >> 2 complete fractures resulting in a segment in the middle. o Comminuted fracture >> >2 fracture fragments (tiny pieces, most likely due to crush injury). o Avulsion fracture >> forceful pull on the insertion of tendon on the bone resulting in breaking a piece of it. o Butterfly fracture >> 2 fracture line that unite, resulting in a triangular segment in between (result from bending force). o Intra-articular fracture >> fracture involving the joints, difficult to get, may need open surgery. @Gatetomedicine 7 Version (1) – Updated on September 2022 Approach to a fracture Clinical assessment: o ABCs (ATLS protocol of primary & secondary survey). o AMPLE history (Allergies, Medications, PMH, Last meal, Events of injury). o Examinations: ▪ Look >> any deformity, assess open or closed fractures. ▪ Feel >> maximal tenderness, pulse distal to injury, sensations. ▪ Move >> avoid ROM or moving injured area, ask to move the fingers or toes. o Salter-Harris fractures types: ▪ Fractures around the physis in pediatric patients are important because if it SALTER dose involve the physis it may lead to growth arrest. S = separated (I) ▪ Type I >> transverse right though the physis. A = Above (II) ▪ Type II >> transverse involving the physis, which then diverts away from the L = Lower (III) T = Through (IV) physis to the metaphysis. R = Ruined (V) ▪ Type III >> transverse goes through the physis & then to the epiphysis (cuts off a piece of bone). ▪ Type IV >> fracture goes across the physis from metaphysis to epiphysis. ▪ Type V >> axial force crushes physeal plate (impaction fracture). Imaging (X-ray): o Role of 2s. o 2 views (at least) >> AP & lateral. o 2 joints >> on above & one below. o 2 sides >> if not sure (e.g. assess growth plate fracture in pediatrics). o 2 radiologist opinions >> you & other one, if both state different opinions, ask a 3rd senior doctor. o 2 times >> one before & another after reduction. @Gatetomedicine 8 Version (1) – Updated on September 2022 Management (brief): o Analgesia >> give strong ones (e.g Morphine). o (1) Reduction: ▪ Close reduction >> IV sedation, apply traction, reverse the mechanism. ▪ Open reduction: Indications (NO CAST): o Non-union. o Open fracture. o Compromised blood flow or neurovascular tissue. o Articular surface mal-alignment (intra-articular fractures). o Salter-Harris type 3, 4, 5. o Trauma patient who needs early ambulation. After open reduction, assess neuro-vascular status & do post-reduction X-ray. o (2) Fixation: ▪ Internal fixation >> screws, plates, pinning, nails, rods. ▪ External fixation >> splints, casts, traction or external fixation devices. o (3) Follow up: ▪ After 2 weeks to evaluate bone healing. ▪ For stress fractures & scaphoid fracture this is also the time to diagnose it radiologically. o (4) Rehabilitation. @Gatetomedicine 9 Version (1) – Updated on September 2022 Compartment syndrome (HIGH-YEILD) Overview: o Definition >> increase pressure within the extremity compartment that compromises the circulation & function of the tissue. o Always suspect it in fractures or damage to an extremity, Why? ▪ The complications are drastic (irreversible tissue death may occur within hours, patient may lose the limb). ▪ The affected limb may appear to be doing well early Crush injuries can cause on, there may be no obvious signs until it’s too late. rhabdomyolysis, which is o Causes: characterized by: ▪ Fractures or trauma (tibial, supracodylar, forearm (1) Hyperkalemia (arrhythmias). fractures). (2) Hyperphosphatemia (hypocalcemia). ▪ Crush or burn injuries. (3) AKI & acidosis. ▪ Vascular injury (post-thrombectomy/embolectomy). Diagnosed by +ve blood dipstick ▪ Drug overdose with prolonged limb compression. with no RBCs on microscopy ▪ Iatrogenic (tight case, poor positioning during surgery). o Clinical features (5Ps): ▪ Pain >> deep, poorly localized, out or proportion to injury or findings, not respond to treatment, increased with passive stretch of muscle. ▪ Paresthesia >> depending on the distribution of nerve compressed in that compartment. ▪ Pallor >> due to compression of vessels (distal hypocirculation). ▪ Paralysis >> later if ischemia established. ▪ Pulselessness >> however, pulse may be present or weakened. ▪ The affected compartment may be tense on palpation. o Investigations & Diagnosis: ▪ It’s generally a clinical diagnosis (high risk patients with pain out of proportion to injury). ▪ Pressure monitors: If clinical exam unreliable (in unconscious patients or children). >30 mmHg suggest compartment syndrome. o Management: ▪ ABCs (as any trauma). ▪ Elevate limb to the level of heart. ▪ Fasciotomy within 4h (decompress all the compartment of the affected limb, not only the affected on). ▪ In 48-72h, wound closure, necrotic tissue debridement. o Complications: ▪ Myonecrosis >> Volkmann’s contracture & deformities, loss of sensations, need for amputation. ▪ Rhabdomyolysis >> AKI, hyperkalemia, hypocalcemia. @Gatetomedicine 10  Version (1) – Updated on September 2022 Shoulder disorders (HIGH-YEILD) Anterior dislocation of the shoulder (most common): o Occur typically in younger patients who play sports or after acute trauma (more joint laxity). o There is increase recurrence risk due to weaker joint ligaments. o Mechanism >> external rotation & abduction. o Clinical features: ▪ Presentation >> pain with difficulty in moving the arm. ▪ Examinations: Look: o Unusual shoulder appearance (asymmetric). o Box-shaped shoulder with loss of its contour. o Humeral head will be prominent. o Typical position >> upper limb held abducted & slightly externally rotated (stuck in which blow resulted in anterior dislocation). Feel (assessment of neuro-vascular structures): o Check for radial & brachial pulses. o Check for axillary nerve (sensations over deltoid area & abduction of arm by deltoid muscle). Move >> reduced ROM + assess movements beyond the deformity (passive & active movement). ▪ Complications: Recurrent dislocations (65-95%). Injury to axillary nerve & artery. Rotator cuff tear. Post-traumatic arthritis. o Investigations: ▪ Shoulder X-ray (rule of 2s) >> it will show the dislocation + it may show hill- Sachs deformity (compression fracture of posterolateral humeral head). o Management: ▪ (1) Closed reduction with IV sedation & muscle relaxation: Longitudinal traction downwards by weight, it will spontaneously reduced in 15min. OR manually by Hennipen technique. OR lift arm to 90 degrees, then externally rotate & adduct until reduced (https://youtu.be/aFEtbMjyGis). ▪ (2) Post-reduction X-rays & neuro-vascular assessment. ▪ (3) Sling immobilization for 3 weeks >> allow for proper healing of ligaments to prevent recurrences. Top image shows humeral head displaced from glenoid and lying inferior to the coracoid process (red arrow); the middle image demonstrates a defect along the posterolateral aspect of the head, which is the Hill-Sach's deformity (green arrow). The lower image is the scapular Y view (blue line outlines scapula). The head lies in a subcoracoid (i.e. anterior location). The white arrows point to the acromion @Gatetomedicine 11 Version (1) – Updated on September 2022 Posterior dislocation of shoulder joint (1-5%): o Causes (uncoordinated muscle contractions): ▪ Seizures (grand-mal/tonic clonic). ▪ Electrical burns & shock. o Presentation >> upper limb held internally rotated & adducted. o Shoulder X-ray (rule of 2s) >> must be 2 sides view, because if one view it can appear normal. o Management >> closed reduction, typically by longitudinal traction (Stimson technique). Inferior dislocation (luxatio erecta) (very rare): o Cause >> hyperabduction (detachment of rotator cuff). o Presentation >> arm held up high (180 degree) & appears shorter. Humeral head may be felt along lateral chest wall. o Management >> closed reduction, +/- surgical repair of rotator cuff muscles. Frozen shoulder (Adhesive capsulitis): o Progressive pain & stiffness of shoulder that resolve spontaneously after 18 months. o Mechanism: ▪ Primary adhesive capsulitis >> Idiopathic (highly associated with DM), resolve spontaneously. ▪ Secondary adhesive capsulitis >> due to prolonged immobilization or following trauma. o Clinical features: ▪ Painful phase (6-9 months) >> gradual onset of diffuse pain. ▪ Stiff phase (4-8 months) >> decreased ROM that impacts functioning. ▪ Thawing or melting phase (5-26 months) >> gradual return of motion. o Investigations >> X-ray usually normal. o Management: ▪ Freezing phase >> physiotherapy, NSAIDs, steroid injections. ▪ Thawing phase >> early physiotherapy, +/- arthroscopy for debridement. @Gatetomedicine 12 Version (1) – Updated on September 2022 Humeral fractures (HIGH-YEILD) Overview: o Common locations: ▪ Surgical neck fracture. ▪ Mid-shaft fracture. ▪ Supracondylar fracture. ▪ Medial epicondyle fracture. o In all cases of humeral fractures: ▪ Diagnosis is done by X-ray (Rule of 2s). ▪ Comment on: Site of fracture (which 3rd). Closed or open fracture. Pattern of fracture. Alignment. Surgical neck fracture: o Occur typically in adults (young adults & elderly). o Causes >> usually direct trauma. o Presentation >> pain, swelling, reduced ROM, ecchymoses over the upper arm & +/- chest (related to damage to surrounding vasculature). o Assessment: ▪ (1) Radial pulse. ▪ (2) Axillary nerve injury (arm abduction & loss of sensations in the shoulder). ▪ (3) Posterior humeral circumflex artery injury (bleeding). o Diagnosis >> X-ray of upper arm (AP, L). o Management: ▪ Depends of fracture severity & degree of displacement. ▪ Closed reduction if necessary, splinting, or ORIF (open reduction & internal fixation). Mid-shaft fracture: o Fracture of diaphysis of the humerus. o Cause >> usually direct trauma. o Presentation >> pain, swelling, reduced ROM. o Assessment: ▪ Radial nerve injury (runs in radial groove posteriorly) >> Wrist drop, loss of sensations of dorsum of hand (1st, 2nd, 3rd fingers). ▪ Injury to deep brachial artery >> ulnar & radial pulses, & comment on perfusion status (warm & pink, pale & cold). o Diagnosis >> X-ray of upper arm. o Management: ▪ 80-90% closed reduction & splinting. ▪ Complicated cases (e.g. comminuted), open reduction & internal fixation. In children, if you see a spiral fracture in the mid-shaft, & the father say the child fell down, suspect child abuse (spiral fracture never happens by falling down) @Gatetomedicine 13 Version (1) – Updated on September 2022 Supracondylar fracture of the humerus: o Typically occur in pediatric cases, rare in adults. o Causes >> fall with hyperextended arm at elbow, fall onto outstretched hand (FOOSH). o Presentation >> pain, arm is held closed to them. o Assessment: ▪ Brachial artery injury >> ulnar & radial pulses, & comment on perfusion status (warm & pink, pale & cold). ▪ Median nerve injury. ▪ Compartment syndrome assessment. o Diagnosis >> lower arm X-ray, if diminished distal pulse consider surgical explore. o Management: ▪ If not displaced: Long arm cast for 4-6 weeks. Must follow up in 1 weeks with X-ray to confirm fracture is still in good position. ▪ If vascular compromise or displaced >> open reduction & internal fixation (vascular surgery may be needed). o Complications: ▪ Median nerve palsy. ▪ Tear or entrapment of brachial artery or compression. ▪ Compartment syndrome. ▪ Volkmann contracture (secondary to reduced perfusion resulting in necrosis of flexor muscles). Medial epicondyle fracture: o Avulsion fracture of medial epicondyle (location of origin of anterior forearm flexer muscles). o Causes >> pitchers (through things overhanded), fall onto outstretched hand (FOOSH). o Presentation >> pain on medial elbow. o Assessment: ▪ Ulnar nerve injury: Loss of abduction & adduction of fingers. Ulnar deviation of wrist. Loss of sensations over medial 1.5 digits & medial palm of hand. o Management: ▪ Depends on fracture severity & degree of displacement. ▪ Closed reduction & splinting OR ORIF. Summary of nerves injury in humerus Surgical neck >> axillary nerve. Radial groove >> radial nerve. Distal humerus >> median nerve. Medial epicondyle >> ulnar nerve. @Gatetomedicine 14