Prosthetics installation effect is poor, stamp this get the best part of amputation
1. Criteria for selecting the best site for lower limb amputation: Except for calf amputation, the principle should be to preserve the longer residual limb. Hemipelvectomy During amputation, efforts should be made to preserve the iliac crest (qià jí) and ischial tubercle according to conditions. The iliac crest (qià jí) is very important for the adaptation and suspension of the socket. It can not only better suspend the prosthesis, but also help reduce the piston movement of the socket during walking. The lack of the ischial tubercle is very detrimental to the weight-bearing of the residual limb.
Hip amputation If possible, the femoral head and neck bones should be retained. Amputation is performed below the lesser trochanter (the bony bump that is palpable and projects posteriorly and medially on the outer surface of the hip joint) without disarticulating the hip joint. From a prosthetic perspective, this method helps to adapt and suspend the socket, and increases the lateral stability and load-bearing area of the prosthesis.
Thigh amputation
● Thigh amputation is often done at the mid-thigh or at the junction of the middle and lower 1/3, because this plane has plump muscles, rich blood circulation, easy wound healing, and is suitable for installing prostheses.
● During amputation, the length of the residual limb should be preserved as much as possible, even if it is a short residual limb; the osteotomy edge should be smoothed with a bone file to prevent postoperative pain in the stump and affect the installation of the prosthetic limb.
● When walking with a prosthetic leg on the thigh stump, the stump will slide up and down, so the tightness of the skin flap must be appropriate.
Knee joint disconnection ● Knee joint dissection is an ideal amputation site, providing excellent weight-bearing on the residual limb. At the same time, the expansion of the femoral condyle helps the prosthesis to hang. Loading the end of the residual limb allows amputees to skip the socket and directly transmit information when standing or walking, thus improving the stability of the prosthetic knee joint.
●
Thigh amputation will remove part of the adductor muscle, thereby weakening its adducting strength, and unable to maintain the normal position of the thigh when the affected side is bearing weight alone. At this time, the body will tilt toward the affected side, resulting in varying degrees of sideways gait. Therefore, the compensatory function of knee joint separation prostheses is significantly better than that of thigh amputation prostheses. Proximal calf amputation As long as the attachment point of the patellar ligament can be preserved, a lower leg prosthesis can be installed by amputation below the tibial tubercle. When amputation, the knee joint should be preserved as much as possible, so as to preserve the complete function of the lower limb. The effect is obviously better than the knee joint separation prosthesis. Note: It is more necessary for children to preserve the epiphysis of the proximal tibia (hóu,the end of the diaphysis, also known as the epiphysis, which is larger and has a smooth articular surface, and the articular surface is covered by articular cartilage).
Calf amputation
The junction of the middle and lower third of the calf is a prime location for calf amputation. Generally, a more ideal prosthetic limb can be installed by retaining a 15cm long residual limb. The middle and distal part of the calf is not suitable for amputation due to factors such as less soft tissue and poor blood supply.
The more professional method of calf amputation is to leave the skin flap on the back side of the calf longer and the front side shorter, then use the back skin flap to wrap the end of the bone, and finally make a suture on the front side of the end of the residual limb. In this way, the bony protrusion at the end of the residual limb is covered by the triceps muscle group of the calf (commonly known as the calf). If the muscles are fixed again, the effect will be better.Ankle dissection and amputation Ankle joint disconnection surgery has high requirements on rescue time, medical technology and medical conditions. When amputating a limb, attention should be paid to preserving the length of the skin behind the heel to facilitate wrapping the amputation site later to prevent pain and discomfort caused by being squeezed when wearing the prosthesis.
Partial foot amputation (hemifoot amputation)
● Partial foot amputation should pay attention to preserving the length of the foot, that is, preserving the length of the forefoot lever arm. If the length is shortened, it will cause great obstacles to fast walking, running and jumping. Therefore, it is very important to have sufficient backward thrust of the forefoot (usually when we walk, the heel touches the ground first, and then the forefoot gives a backward thrust). ●Regarding hemifoot amputation, many friends are complaining that there are too many disadvantages after surgery, such as poor walking gait, blistering when walking with prosthetic limbs, and easy clubfoot, etc. I will publish an article on this issue in the next issue and give suggestions.Syme Amputation
● Syme amputation is an ideal amputation site. Although the amputation level is equivalent to the ankle joint separation, the stump is covered by complete and good heel skin, which is stable, wear-resistant, and not easy to rupture. The residual limb has good load-bearing capacity and strong walking ability, which is conducive to daily life activities. Its function is obviously better than the calf prosthesis. ● When performing Syme amputation, it is best to remove the excess portion of the medial and lateral malleolus during the operation, taking into account the problem of adaptation to the prosthetic socket and to reduce the appearance of the stump caused by enlargement.2. The optimal selection criteria for the upper limb amputation site: try to preserve the function of the fingers Shoulder joint disconnection
Disarticulation of the shoulder joint requires the removal of all the shoulder girdle, scapula, clavicle and the muscles attached to them. This will cause the support points of the socket to be destroyed, so it will be difficult to wear the prosthesis, and the humeral (gōng) head should be preserved as much as possible.
This not only preserves a better appearance, but also facilitates the fitting, suspension and stability of the prosthetic socket. From a biomechanical point of view, preservation of the humeral head facilitates the movement of the prosthetic elbow joint and hand hook.
Upper arm amputation When an upper arm is amputated, the length of the residual limb should be preserved as much as possible. The function of the upper arm prosthesis depends on the lever arm length, muscle strength and shoulder joint range of motion of the residual limb. At the same time, a long residual limb is conducive to the suspension and control of the prosthesis.
It should be noted that prosthetic fittings for patients with above-elbow amputations must include an internal elbow joint locking device and an elbow joint rotation disc. The purpose of the elbow joint locking device is to stabilize the elbow joint in a fully extended position, a fully flexed position, or a position between extension and flexion. The rotating disk device is used to replace the rotation of the humerus. The elbow joint locking device is located at the distal end of the socket and is about 3.8cm long. For aesthetic reasons, the elbow joint of the prosthetic limb should be at the same level as the healthy elbow joint. Therefore, when performing above-elbow amputation, the level of osteotomy should be at least 3.8cm proximal to the elbow joint line, leaving enough space for the installation of this device.
The assembly and function of the prosthetic limb after humeral condylar amputation are the same as those after elbow joint disconnection. Therefore, when conditions permit amputation through the humeral condyle level, amputation should not be performed at the supracondylar location, because elbow joint disconnection prostheses are superior to upper arm amputation in all aspects.
Disconnection of elbow joint The distal end of the humerus is relatively wide and has a strong ability to suspend and control the prosthesis. Therefore, if the distal end of the humerus can be preserved, elbow joint dissection is an ideal amputation site and is preferable to above-elbow amputation. Because if the limb is amputated above the elbow joint, the rotation of the humerus cannot be directly transmitted to the prosthesis, which will reduce the sensitivity of the movement.
Forearm amputation When performing forearm amputation, even a short stump length (4 to 5 cm long) must be preserved. This method is preferable to elbow joint disconnection or above-elbow amputation. From a functional point of view, it is very important to preserve the amputee's own elbow joint: the better the muscles of the residual limb are preserved, the easier it is to obtain good electromyographic signals, and it is also more helpful for assembling myoelectric prosthetic hands.
Wrist amputation
The effect of transcarpal amputation or wrist dissection is better than that of transforearm amputation. This method preserves the distal radioulnar joint of the forearm and can retain all the rotation function of the forearm. Although only 50% of the pronation and supination movements are transmitted to the prosthesis, these movements are very important and valuable to the patient.
Paracarpal bone amputation
If you want to recover well after surgery, the choice of amputation site is very important. Encountering difficulties is helpless, but choosing the scientifically correct method can minimize the damage and allow us to return to normal life as quickly and in the best condition.
Scan the QR code below on WeChat to follow the 51 Prosthetics official account and learn about Yibu.com’s online sales platform for prosthetics and orthotics