Limbs, Spine and Vascular Pathology Flashcards
What is carpal tunnel syndrome?
Median nerve compression at the wrist as it passes under the flexor retinaculum.
Symptoms include pain, paraesthesia, and numbness in the radial 3 1/2 digits, weakness, and atrophy of the thenar muscles.
Symptoms may be worse at night and provoked by activities involving prolonged gripping e.g. driving
What are the causes of carpal tunnel syndrome?
- Idiopathic
- Endocrine: pregnancy, hypothyroidism, acromegaly, DM
- Inflammatory: RA
- Mechanical: Osteophytes (OA), Previous fracture
What are the management options of for carpal tunnel syndrome?
- Conservative: address the underlying cause, night time splint (30-degree wrist extension)
- Medical: corticosteroid injection
- Surgical: Carpal tunnel decompression (open/endoscopic)
How is open carpal tunnel decompression performed?
- Full pre-operative assessment
- Explain the operation to the patient, obtain informed consent and confirm the correct side
- LA (most commonly)
- Skin preparation and draping (including limb exsanguination and tourniquet inflation)
- Patient supine, arm abducted and placed on arm table
- Longitudinal incision in line with the radial aspect of ring finger, distal to the distal wrist crease, no further than the line of the 1st web space
- Cut skin, fat and palmar fascia
- May insert a McDonald’s Dissector under the flexor retinaculum to protect the median nerve
- Divide the flexor retinaculum under direct vision, ensuring adequate release distally to the fat pad and proximally to the antebrachial fascia
- Observe the median nerve
- Tourniquet release and hemostasis
- Suture skin
- Apply non-adherent dressing, wool, and crepe bandage
What are the complications of carpal tunnel decompression?
- Immediate Damage: median nerve (recurrent motor branch), palmar arch (superficial and deep), ulnar nerve, and artery
- Early: hematoma, infection, wound dehiscence
- Late: incomplete symptom resolution, CRPS, Pillar Pain*, Recurrence of symptoms
*Pillar Pain: a frequent symptom following carpal tunnel release. The pain is located at the base of the hand in the heel of the palm. The muscles at the thumb base (thenar eminence) and the muscles at the base of the small finger (hypothenar eminence) are the usual areas of tenderness.
How would you perform a hemiarthroplasty via an anterolateral (Hardinge) approach?
- Full pre-op assessment.
- Explain operation to patient and obtain informed consent, confirm correct side.
- Patient in lateral position under GA.
- Skin preparation and draping.
- Longitudinal skin incision 2.5cm behind ASIS, to tip of greater trochanter.
- Extend the incision vertically down along the anterior margin of the greater trochanter for 10-15 cm.
- Incise tensor fascia lata and divide gluteus medius.
- Access to the femoral neck and capsule is gained. These are divided.
- Cut the femoral neck with a power saw.
- Externally rotate the leg to allow the femoral head to be removed from the acetabulum.
- Measure femoral head size.
- Femoral shaft reamed, trial reduction attempted.
- Hammer in prosthesis to rest on calcar femorale.
- Reduce the hip and check stability.
- Repair muscles.
- Close skin.
- Check X-ray in 24h to confirm prosthesis position.
Outline the common approaches to the hip joint, indicating those nerves that are at risk of immediate damage?
- Anterolateral (Hardinge) Approach:
a. most common approach
b. access between tensor fascia lata and gluteus medius
c. superior gluteal nerve is at risk (supplies gluteus medius and minimus, such that division causes loss of hip abduction and Trendelenberg gait) - Posterior Approach:
a. Skin incision centered on posterior aspect of greater trochanter and curved proximally towards the PSIS
b. Dissect through subcutaneous tissue.
c. Split gluteus maximus along its fibres.
d. Identify and retract piriformis (the superior gluteal artery is above, the inferior gluteal and sciatic nerve are below).
e. Divide the short external rotator muscles at their insertion at the medial aspect of the greater trochanter (piriformis, gemelli & obturator internus). Repair is then advisable.
f. Sciatic nerve is at risk. - Anterior (Smith-Peterson) Approach:
a. Used in paediatric orthopaedics to correct congenital dislocation of the hip.
b. Skin incision from 2cm below midpoint of iliac crest, curved inferiorly to ASIS and extended distally.
c. Between tensor fascia lata (superior gluteal nerve at risk) & sartorius (femoral nerve at risk).
d. Divide rectus femoris & anterior 1/3 of the gluteus medius.
Nerve: Lateral femoral cutaneous nerve of thigh is at risk. - Lateral Approach:
a. Skin incision centred on greater trochanter. Incision extended proximally in line with fibres of gluteus medius and distally in line with the femur.
b. Involves splitting tensor fascia lata, gluteus medius & minimus (short external hip rotators).
Nerve: Superior gluteal nerve is at risk. - Medial Approach:
a. Between adductor longus and gracilis.
b. Then between adductor magnus and brevis.
Nerve: Posterior branch of obturator nerve is at risk.
What are the complications of hemiarthoplasty?
Immediate:
a. Acetabulum/Femur fracture
b. Haemorrhage
c. Neurovascular damage
Early:
a. Dislocation
b. Infection
c. DVT/PE
d. Fat embolism
Late:
a. Dislocation
b. Infection
c. Loosening
d. Periprosthetic fracture
e. Leg length discrepancy
What is an ingrown toenail?
A condition where the nail plate grows into the lateral nail fold. It is often painful & presents with signs of infection or inflammation.
What are the treatments for an ingrown toenail?
Conservative:
a. Good nail care
b. Cut nail transversely
c. Analgesia
d. Antiseptic dressings
Surgical:
a. Simple nail avulsion: for acutely infected toenails, high incidence of recurrence
b. Wedge excision: excision of affected nail segment and nail bed down to periosteum
Zadek’s procedure: total radical excision of nail and nail bed
How is Zadek’s Procedure performed?
- Full pre-op assessment
- Explain operation to patient, obtain informed consent and confirm correct digit
- GA/LA ring block with 1% plain lignocaine.
- Skin preparation & draping (including digital tourniquet)
- Remove nail plate from nail bed
- 2 small incisions are made at the corners of the nail bed, extending to the distal skin crease
- Excise germinal matrix & curette the nail bed down to the periosteum
- 80% phenol may then be used to abate any remaining germinal matrix
- Tourniquet release
- Haemostasis
- Suture skin flaps
- Apply non-adherent dressing
- Post-operative advice includes leg elevation for 1 day & mobilisation as pain allows
What are the contraindications to the Zadek’s Procedure?
- Acute infection
- Peripheral Vascular Disease
What are the complications of the Zadek’s Procedure?
Early: pain and would infection
Late: recurrence, osteomyelitis, septic arthritis
What is compartment syndrome?
Discrete osteofascial compartments exist within the limbs. Pressure may become elevated within these compartments, usually following trauma e.g. tibial fracture.
The following events occur:
1. Increased compartment pressure
2. Increased venous pressure/reduced venule (not arteriole) diameter
3. Decreased arterio-venous pressure gradient
4. Decreased tissue perfusion
5. Tissue necrosis e.g. nerve and muscle
What are the clinical features of compartment syndrome?
(6 x P’s of compartment syndrome)
- Pain: out of proportion to injury and often resistant to potent analgesia (pain is worse on passive muscle stretch). Early sign.
- Pressure: a difference of less than or equal to 30mmHg between compartment and diastolic pressures.
- Paraesthesia/sensory loss: may be a useful early sign in nerves crossing involved compartments.
- Pallor: late sign.
- Pulselessness: late sign.
- Paralysis: late sign.
