Amputation is the surgical removal of all or part of a limb or extremity. For students of Prosthetics & Orthotics (P&O) and Physiotherapy, understanding the precise levels of amputation, the rigorous management of the residual limb (stump), and the complex pathophysiology of Phantom Limb Pain (PLP) is critical for academic exams and clinical practice.
1. Levels of Amputation
The level of amputation determines the type of prosthesis required and the energy expenditure for the patient. Higher amputations generally result in higher energy costs during ambulation.
Lower Limb Amputations
| Level Name | Anatomical Description | Prosthetic Consideration |
|---|---|---|
| Hemipelvectomy | Resection of the lower half of the pelvis. | Requires a Canadian Hip Disarticulation prosthesis. |
| Hip Disarticulation | Amputation through the hip joint; pelvis remains intact. | Socket must bear weight on the Ischial Tuberosity. |
| Transfemoral (AKA) | Amputation through the femur (Above Knee). | Socket types: Quadrilateral or Ischial Containment. |
| Knee Disarticulation | Amputation through the knee joint. Femur intact. | End-bearing stump; Condyles provide suspension. |
| Transtibial (BKA) | Amputation through the tibia and fibula (Below Knee). | Ideal length: Junction of upper and middle third of the leg. PTB (Patellar Tendon Bearing) socket used. |
| Syme's Amputation | Ankle disarticulation with heel pad preservation. | Excellent end-bearing capability. |
| Chopart & Lisfranc | Partial foot amputations (Mid-tarsal & Tarsometatarsal). | High risk of Equinus deformity. |
Upper Limb Amputations
- Forequarter: Removal of the arm, scapula, and clavicle.
- Shoulder Disarticulation: Removal of the arm at the shoulder joint.
- Transhumeral: Above elbow amputation.
- Elbow Disarticulation: Disarticulation at the elbow joint.
- Transradial: Below elbow amputation (Most common upper limb major amputation).
2. Stump Care & Management
Proper care of the residual limb is the foundation of successful prosthetic rehabilitation. A poorly managed stump can lead to delayed fitting, skin breakdown, and infections.
A. Edema Management & Shaping
- Figure-of-8 Bandaging: Elastic bandages (Crepe) are applied in a figure-of-8 pattern. Never use circular bandaging as it creates a tourniquet effect.
- Shrinkers: Elastic socks used to control edema once the sutures are removed.
- Rigid Dressings (IPOP): Immediate Post-Operative Prosthesis helps in early ambulation and prevents edema.
B. Hygiene & Skin Care
- Wash the stump daily with mild soap and warm water; dry thoroughly.
- Do not apply lotions or creams immediately before wearing the prosthesis (causes slippage).
- Inspect the skin daily (using a mirror) for redness, blisters, or abrasions.
C. Desensitization Techniques
To prepare the stump for the pressure of the socket, desensitization is required:
- Tapping: Gently tapping the stump end.
- Massage: Deep friction massage to prevent adherent scars.
- Texture rubbing: Rubbing with cotton, then wool, then rougher fabrics to normalize sensation.
3. Phantom Limb Pain (PLP) Management
Definition: Painful sensation perceived in the missing portion of the limb. It differs from Phantom Sensation (non-painful feeling that the limb is still there) and Residual Limb Pain (pain in the remaining stump).
Pathophysiology (Theories)
- Cortical Remapping (Neuroplasticity): The area of the brain (somatosensory cortex) representing the amputated limb is "taken over" by adjacent areas (e.g., face or adjacent limb), causing crossed signals.
- Neuromas: Tangled nerve endings at the cut site generating abnormal impulses.
Management Strategies
| Modality | Technique/Mechanism |
|---|---|
| Mirror Therapy | Gold Standard. The patient views the intact limb in a mirror, tricking the brain into thinking the amputated limb is moving pain-free. This helps reverse cortical remapping. |
| TENS | Transcutaneous Electrical Nerve Stimulation uses the Gate Control Theory to block pain signals. Applied to the contralateral limb or proximal to the stump. |
| Medical Management | Use of anticonvulsants (Gabapentin, Pregabalin) and antidepressants (Amitriptyline) for neuropathic pain. |
| Prosthetic Use | Early fitting and weight-bearing can provide sensory feedback that reduces PLP. |
Frequently Asked Questions (FAQs)
The ideal shape is Conical or Cylindrical. A bulbous end (swollen at the bottom) makes it impossible to don the socket, while a pointed (conical) shape allows for total contact.
Circular bandaging creates a "tourniquet effect," restricting blood flow and causing bulbous swelling at the distal end (choking effect), which delays healing.
Syme's is an ankle disarticulation (removal of the foot but keeping the heel pad). Chopart is a mid-tarsal amputation (between talus/calcaneus and cuboid/navicular), often leading to equinus deformity due to muscle imbalance.
Exam Quiz: Amputation & Prosthetics (10 MCQs)
Test your knowledge. Click the correct option to see the answer and reasoning.
1. Which amputation level involves the disarticulation of the ankle joint with preservation of the heel pad?
Syme's amputation is an ankle disarticulation where the malleoli are trimmed and the heel pad is preserved for end-bearing capability.
2. What is the primary purpose of Figure-of-8 bandaging?
Figure-of-8 bandaging applies graded pressure (distal to proximal) to reduce edema and shape the stump into a cone for prosthetic fitting.
3. Mirror Therapy is primarily used to treat:
Mirror therapy utilizes visual feedback to reorganize cortical mapping, effectively reducing Phantom Limb Pain.
4. In a Transfemoral amputation, which contracture is most common?
Due to the loss of adductor muscles (specifically Adductor Magnus) and the pull of the Iliopsoas and Gluteus Medius, the stump tends to go into Flexion and Abduction.
5. The "Patellar Tendon Bearing" (PTB) socket is designed for which level of amputation?
The PTB socket is the standard design for Transtibial (Below Knee) amputations, utilizing the patellar tendon as a major weight-bearing area.
6. Which of the following is a disadvantage of a Hip Disarticulation amputation?
Hip disarticulation results in very high energy consumption (up to 200% more than normal walking) because the patient must use trunk motion to swing the heavy prosthesis.
7. The main cause of Equinus deformity in Chopart amputation is:
In Chopart amputation, the dorsiflexors are removed/detached, leaving the strong Gastrocnemius-Soleus (plantarflexors) unopposed, pulling the foot into Equinus.
8. What is "Neuroma"?
A neuroma is a benign growth of nerve tissue causing pain, occurring when nerve axons continue to grow after being cut and form a ball.
9. Which medication is commonly used as a first-line treatment for neuropathic Phantom Limb Pain?
Gabapentin (and Pregabalin) are anticonvulsants that are specifically effective in treating neuropathic pain like PLP. NSAIDs like Ibuprofen are generally ineffective.
10. The ideal length for a Transtibial stump is:
This length provides the best lever arm for control while leaving enough room for the prosthetic components (foot and pylon) below.
References
- Lusardi, M. M., & Jorge, M. (2013). Orthotics and Prosthetics in Rehabilitation. Saunders/Elsevier.
- Bella J. May. (2002). Amputations and Prosthetics: A Case Study Approach. F.A. Davis Company.
- Smith, D. G. (2004). Atlas of Amputations and Limb Deficiencies. American Academy of Orthopaedic Surgeons.
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