Custom Socket Liners Fill In For Difficult Residual Limbs
30 Aug 2017
The introduction of gel socket liners in the early 1990s opened new vistas of comfort and improved prosthesis suspension for lower-limb amputees and spawned a steady stream of new liner designs and materials, which continues today.
Most prosthetic liners are off-the-shelf products of uniform gel thickness throughout and available in various sizes.
These products work well for most transtibial and some transfemoral amputees; however, those with residual limbs that are particularly bony, short, uneven, deeply scarred and/or invaginated often experience pain when wearing their prosthetic limb and sometimes difficulty in maintaining suction suspension.
Alpha® assembly™ custom liners can extend a comfortable, secure prosthetic fit to individuals with one or more of those limb characteristics. These liners are made to conform to the unique variations of a challenging residuum, as modeled by an OMEGA® Tracer® computer-assisted assembly (CAD) system or a plaster cast of the limb. In the absence of a CAD image, the amputee’s prosthetists can participate in the fabrication of the custom liner through an interactive online consultation with the designer, known as Web Assist.
The resulting liner will be one of a kind. assembly liners feature varying gel thickness at strategic points that contact difficult areas on the residual limb surface. The standard 6mm gel thickness can be decreased as needed or increased up to 12mm in the distal end and up to 15mm over invaginations. The additional padding enhances comfort; the closer fit improves suction continuity.
The first assembly liners were available only for transtibial amputees; transfemoral liners are now offered as well. Both can be ordered in a suction version or incorporating a distal attachment for a locking pin. assembly liners come in one of three fabric coverings (two for the transfemoral version), many sizes, and three fabric colors.
Custom Liner Helps Defeat Osteomyelitis
After almost four decades as a Level 4 (high-activity) amputee, David T., 59, suddenly faced a major curtailment of his activities.
A persistent infection in the distal end of his very short (3 inches) transtibial limb was diagnosed as possible osteomyelitis. If the prescribed antibiotics, or something else, didn’t defeat the infection and attendant swelling, further surgery would be the likely next step.
When your limb is as short at David’s, more residual limb surgery is spelled “major lifestyle change.”
Loss of the knee joint would mean having to learn to walk again, with likely ramifications for his 10 miles-a-week running regimen and frequent long-hour days as a county executive. Though already wearing an advanced prosthetic system, David consulted his prosthetist to determine what else could be done.
Together, they discovered that the standard prefab locking pin liner David was wearing was allowing considerable movement of his residual limb within the socket. Moreover, despite having little sensation in the distal end of his limb, he was experiencing significant discomfort on the fibula head. Compounding the issue were the significant irregularities – scarring, and bony prominences – on his residual limb resulting from amputation necessitated by an auto accident at age 21.
The prosthetic solution was to switch to suction suspension and an Alpha assembly custom liner. The new interface produced almost-instant benefits: David noted an immediate pain reduction when wearing his prosthesis, even after having it on for up to 16 hours a day, and limb movement within the socket was all but eliminated. “I asked my wife to try to pull the leg off,” he recalls. “She really tried…and she couldn’t do it.”
With the new liner in place, David’s edema subsided within 10 days, and the infection came under control in 30. “My doctor treated my problem, my prosthetist treated the cause,” he says. He has temporarily traded running for swimming and biking until he can be reasonably confident the infection will not recur.
The remainder of David’s prosthetic system consists of a hybrid PTB (patellar tendon-bearing)/hydrostatic socket, Endolite Elite all-terrain foot, and suspension sleeve incorporating a suction valve.
If need a comfortable prosthetic or prosthetic liner, be sure to contact LeTourneau Prosthetics in Beaumont, Nederland or Jasper, Texas. Your initial consultation is free.