Abstracts from the Scientific Program Presented at the 1989 Annual Meeting of the Association of Children's Prosthetic-Orthotic ClinicsChicago, Illinois VASCULAR AMPUTATION IN CHILDREN

Francis J. Trost, MD, Shriners Hospital for Crippled Children, 3641 Towndale Drive, Bloomington, MN 55431

Vascular amputations in newborns and- young children are an unusual occurance. They are most commonly associated with the elderly. With the onset of heroic lifesaving treatment of seriously ill infants and distressed newborns, however, the incidence of vascular amputations appears to have increased. The authors studied 8 children whose proximate cause for amputation was vascular dysfunction, as to etiology, associated conditions and ultimate level of amputation. Various causes were discovered; several involved venous or arterial catheterization. Vascular amputation was first reported in 1828 by Martini. Further documentation and discussion of the problem have been infrequent. Differential diagnoses of vascular causes for amputation in children include arterial and venous catheterization, heart defects and disease, thrombocytopenia, familial coagulation defects, arterial anomalies, pressure, septic emboli and mucocutaneous lymph node syndrome (Kawasaki Disease). Treatment must be prompt and vigorous. Supportive care, anticoagulation, balloon catheter thrombectomy, fasciectomy and surgical thrombectomy have been used with varying success.


Madan M. Telikicheria, MD, 261 Mack Boulevard, Detroit, MI 48201

Full weight bearing prosthetic ambulation should begin as soon as possible following amputation surgery. Earlier methods of immediate postoperative prosthetic fitting permitted only limited weight bearing through the prosthesis under careful supervision. We achieved prosthetic bearing by using an ischial weight bearing prosthesis with the socket open distally, bypassing weight distribution through the edematous and painful limb immediately following surgery. The prosthesis is prefabricated with an adjustable socket. A bail-lock knee provides stability during standing. We used this prosthesis on 12 patients with above-knee and below-knee amputations done for peripheral vascular disease, trauma, and malignant tumor. One patient had guillotine below-knee amputation. Initial application of the prosthesis ranged from 2 to 14 days following amputation. Patients achieved independence in ambulation with double leg support using the prosthesis and a standard walker and independence with basic self care I to 2 weeks after fitting the prosthesis.


R. D. Beauchamp, MD, S. P. Pirani, Suite 210, 650 West 41st Avenue, Vancouver, British Columbia V5Z 2M9 Canada

Classifications of proximal femoral focal deficiency (PFFD) to date have all been based on the x-ray appearance of the ossified skeleton. This is because the soft tissue abnormalities of the deformity have been poorly described. The advent of magnetic resonance imaging (MRI) now allows much better appreciation of soft tissue anatomy in a non-invasive manner. The authors have done MRI on 10 patients with PFFD located through the Amputee Clinic at the British Columbia's Children's Hospital. One patient also had angiography. This presentation describes the MRI anatomy of PFFD based on the abnormalities of both soft and hard tissues.


John S. Blanco, MD; John A. Herring, MD, Texas Scottish Rite Hospital, 2222 Welborn Street, Dallas, TX 75219

The authors functionally assessed I I patients with congenital Chopart level foot amputations. The average age was 6 years 9 months (range I + I I to 18 + 8). The authors examined each patient noting leg length and calf circumference, range of motion at the ankle and subtalar joints, and recorded residuum appearance. The authors timed the patients running a 50 yard dash and measured a standing broad jump performance. Patients with congenital Chopart amputations functioned within normal limits in all the tests. No patient had a plantar flexion deformity. A slipper style shoe filler or ankle foot orthosis with a foot plate and shoe filler is an easily fabricated and very functional prosthesis. The Chopart foot has many advantages compared to a Syme's level amputation: maintenance of functional length of the extremity, preservation of a broad weight bearing surface, and intact plantar fat pad.


Doreen Bartlett, BSc, PT; Carole Jacques, BSR, British Columbia's Children's Hospital, 4480 Oak Street, Vancouver, British Columbia, V6H 3V4 Canada

A child with multiple congenital anomalies consistent with a diagnosis of VACTERL association will be described. Early medical and surgical management will be outlined. Subsequent discussion will focus on problems encountered in prosthetic fitting and physiotherapy and occupational therapy intervention. Social problems which complicated this child's treatment will be presented. Early management of life threatening anomalies was relatively straight forward and successful. Ongoing management in orthopedic and developmental areas poses numerous challenges to all limb deficiency team members.


Cheryl Withrow, OTR, Shriners Hospital for Crippled Children, 2100 North Pleasantburg Drive, Greenville, SC 29609-3194

The objective of this case report is to encourage other Shriners Hospitals, children's hospitals and clinics to sponsor and hold symposiums on arthrogryposis. The Greenville Unit held such a symposium on July 9, 1988, for 89 professionals, parents, siblings, and children and adults involved with arthrogryposis. We had an orthopedist and geneticist speak, and representatives from Child Life, Occupational Therapy and Physical Therapy Family Services led a panel of parents concerning raising a child with arthrogryposis. The symposium was beneficial for all who attended, but especially for the families and adults. The support and knowledge they gained from each other could not have been achieved in a normal clinic setting.


Deborah J. Bolding, OTR, Shriners Hospital for Crippled Children, 1701 19th Avenue, San Francisco, CA 94122

A play group was developed for children 6 years and younger with upper-limb deficiency to 1) evaluate development, especially gross and fine motor skill and activities of daily living; 2) observe and foster integration of upper-extremity prostheses into play activities; 3) make recommendations to caregivers about improving prosthetic wear and use; 4) arrange individual treatment sessions as needed; and 5) report to team members regarding fit and use of the prostheses. The group is staffed by one or two occupational therapists and one recreational therapist. Children enjoy the play setting, and are more willing to demonstrate use of the prostheses than in a clinic setting. Therapists are able to consult with parents after observing the children use the prostheses. An added benefit is the opportunity for parents to observe other children with a variety of ages, skills and types of prostheses. Approximately half the children scheduled for prosthetic clinic have been attending the play group. A survey of parents is in progress to determine effectiveness of the program and future needs. Although this program was developed in a hospital-based prosthetics clinic, small groups might also be developed in other settings.


Robert Radocy, Children's Hospital, 1056 East 19th Street, Denver, CO 80218

Snow skiing, for children missing a hand, can be enhanced with a specifically designed prosthetic device. An I I year old congenitally hand deficient boy has participated in the Denver Children's Hospital Handicapped Ski Program at Winter Park, Colorado. He skied for several seasons with an ADEPT bodypowered terminal device and is a skilled prosthetic user. He has used the new All Terrain Ski Terminal Device, or AT-Ski-TD, since the onset of the 1988/89 ski season. He initiated use of the AT-Ski-TD immediately after instruction and responded positively to its function. He continues to progress in Alpine skiing utilizing the device and seems to be performing well for his age. The device uses body power for pole extension and planting and automatically flexes the pole when body power is relaxed. The device's safety features functioned reliably, and no injuries were incurred during the season.


Jack R. Engsberg, PhD; James A. Harder, MD; Kathy G. Tedford, PT, University of Calgary, 2500 University Drive NW, Calgary, Alberta, T2N 1N4 Canada This investigation compared standing, walking and running characteristics of 4 below-knee amputee (BKA) children with those of 11 nondisabled children (mean, 8 years). Three dimensional cinematographic and force data were simultaneously recorded in a laboratory setting. Three trials of data were collected for each subject for each activity. One way ANOVA was used to determine any significant differences (p less than 0.05). Results from 3 testing sessions during a 1.5 year period indicated that BKA children had standing, walking and running patterns that were significantly different from those of nondisabled children. For example, stance time for the nonprosthetic limb was significantly different than those for the nondisabled. Generally, significantly greater loads were placed on the nonprosthetic limb than on the limbs of the normal children. A dichotomy may exist for determining the most appropriate activity patterns of BKA children. It may be in the best interest of these children to behave differently from normal children because the prosthesis is functionally different from a normal limb. The greater loading pattern on the nonprosthetic limb may contribute to the propensity for adult BKAs to manifest osteoarthritis in that limb.


Doreen Bartlett, BSc, PT; Bonnie Sawatzky, BPE, British Columbia's Children's Hospital, 4480 Oak Street, Vancouver, British Columbia, V6H 3V4 Canada

One goal in management of children with lower extremity amputations is to improve locomotor efficiency. Traditionally, this has been evaluated by measuring oxygen uptake in the gait laboratory; however, this method is not practical for routine clinical assessment. Researchers at the Orthotic Research and Locomotor Assessment Unit in Shropshire, England have proposed the use of heart rate and speed of walking to calculate the physiological cost index (PCI). The authors investigated the reliability and clinical uses of the PCI in the assessment of limb deficient children. Baseline heart rate is recorded using an ambulatory pulse rate meter. The child is then asked to start walking at a comfortable speed in the 25m walkway. Once a steady state is reached, heart rate and time are recorded after each excursion for a total of 8 recordings. Average heart rate and speed, and subsequently, the PCI are recorded. PCI's of children with several different levels of lower extremity amputation will be presented. Reliability of this method will be presented, as will its usefulness in evaluating change in prosthetic prescription, surgical intervention, effect on an exercise program, and effect of ambulatory aids. Concerns regarding validity will be discussed.


Edward Skewes, CPO; Leon Kruger, MD, Shriners Hospital for Crippled Children, 516 Carew Street, Springfield, MA 0 1104

Self-suspending sockets have been prescribed for Syme's amputees for many years. The design of such a socket may vary. Earliest Syme's sockets were made of carved willow wood with a lacer. With the advent of plastic laminate, the Canadian type Syme's prosthesis was developed. Medial or posterior windows were used to permit the increased distal diameter of the residuum to enter the socket. The lower trimline socket without window was developed so that the liner could slip into the rigid socket and permit supramalleolar suspension. Appearance was not ideal; function was good. When the technique failed in small children, if was necessary to raise the trimline and use alternative suspension. Newer molding techniques enable fitting young patients successfully with low profile Syme's prostheses. The lower trim allows a greater range of knee flexion, permits the patient to kneel, and does not tear the clothes as often as higher trimlines. Thirty-one patients have been fitted with low profile Syme's prostheses using a Pelite insert, polyester socket, and a Syme's foot. Patients range from 13 months to 19 years of age. There were 14 males and 17 females. All old wearers were previously fitted with patellar tendon bearing level Syme's prostheses. Three patients have returned to the higher trimline because they were unable to accept full end-bearing. All other patients report that they are more comfortable with the lower trimline. No problems with skin irritation or excessive rotation between the socket and the residual limb occuffed.


Francis J. Trost, MD, 3641 Towndale Drive, Bloomington, MN 55431

Fifty-five energy storing feet fitted to 51 amputees of various levels were studied. Clinical evaluation was made of the patients' impression of these feet. Gait laboratory analysis of 4 amputees using conventional and energy storing feet was performed. The detailed study was conducted at the Shriners Hospital for Crippled Children in Minneapolis; the authors experience at the Minneapolis Veterans Hospital in adult dysvascular amputees was added to the study. Children were questioned as to general impression, specific activities and adaptability. Problems with the energy storing feet were also analyzed. The effect of these feet on the determinants of gait and oxygen consumption were analyzed.


Edward Skewes, CPO; Leon M. Kruger, MD, Shriners Hospital for Crippled Children, 516 Carew Street, Springfield, MA 01104

Stubby prostheses are short, non-articulated artificial limbs with wide based bottoms. The socket design may vary from quadrilateral to ischial containment with or without Pelite inserts. Suspension is achieved with Silesian bandage, waist belt or suspenders. Rocker bottoms provide adequate standing balance and are an alternate to flat bottoms. These prostheses offer patients with a lower center of gravity, greater sense of stability and more ease in standing and walking. Stubbies provide opportunity to develop better trunk balance for future use of articulated prosthetic limbs. The child is quick to achieve standing balance and confident walking without the fear of falling. Recently fitted patients are presented as well as a 30 year follow-up.


Nancy Bradley, PT; David Firlik, CP, Area Child Amputee Center, 235 Wealthy Street, Grand Rapids, MI 49503

An alternative prosthetic suspension for the very young child amputee is needed. Toddlers present unique challenges in socket suspension because of fleshiness, immature underdeveloped bony prominences, and high activity. Historically, suspension of the below-knee prosthesis for the young child was accomplished by one, or a combination of the following: waist belt, condylar strap, shoulder harness, side joints, and leather corset. These suspensions can be cumbersome, difficult to apply and adjust, and inadequate during the many position changes and activities of a toddler. Within the past year, the Area Child Amputee Center has successfully used neoprene sleeve suspensions on 8 children under the age of 4 with acquired, congenital or post-conversion deficiencies. While it is difficult to measure the value of different types of suspensions, neoprene sleeves seem to demonstrate clear advantages: decreased confinement and restriction of harnessing, increased ease of installation, and improved suspension and appearance. The prosthetic considerations of neoprene sleeve size ranges, proper size selection, fitting and application of the prosthesis will be addressed.


Robert Leimkuehler, CPO, Cleveland Western Reserve University Hospitals 2074 Abington Road, Cleveland, OH 44106

An 8 year old child came to our facility from Yugoslavia. He has bilateral proximal femoral focal deficiencies with severe anterior bowing of the tibiae, equinovarus deformaties, malformed hands and webbed digits of both hands and feet. We will present our prosthetic management.


Thomas J. Koelker, CP; Susan C. Labbard, RN, Shriners Hospital for Crippled Children, 3101 SW Sam Jackson Park Road, Portland, OR 97201

Educational material on prosthetics was produced for 4-12 year olds (some of whom need an artificial limb). The Hal O'Leary disabled skier doll with a residuum in place of a left leg cheerfully demonstrated what it was like to come to clinic and be fitted with a prosthesis. Children and families were educated while waiting for the prosthesis. A prosthetist and pediatric nurse worked with children in the hospital setting, then photographed "Hal" in typical life-like scenes. "Hal" remains cheerful during his visit, illustrating a comfortable environment for children. Male and female narration provided variety. Language and photographs were selected from a child's perspective to decrease anxiety while increasing natural curiosity. This developed into a teaching tool for classrooms promoting positive awareness of children with disabilities and showing multidisciplinary effort to meet the needs of our population. The videotape can be used by prosthetists desiring to do teaching when budget and time are limited, both in the hospital and the classroom. Sample questions are provided for evaluation of teaching. A picture book can be adapted for individual sessions.


Lisa Barker, LPT; Barbara Homlar, OTR/L; Katy Plowden, LPT; Cliff Robbins, CPO; Jan Roth, OTR/L, 3300 Efland Avenue, Cincinnati, OH 45229 Patient was born at 30 weeks gestation with severe hydronephrosis, hypoplastic lungs, prune belly syndrome and congenital amputation of left foot and right lower extremity. He has had a vesicostomy, tracheostomy, and currently receives 34% oxygen. The long-term goal is independent ambulation with the least restrictive assistive devices. Mobility is being provided by adapting a prone support walker with seat. A prosthesis for the left lower limb will be fabricated. Child has demonstrated improved sitting balance through the use of the abdominal binder and bucket seating. He has learned to associate volitional movements of left lower limb with movements of the prone support walker with seat. The physiological benefits for this child are opportunity for increased bone density through weight bearing and strengthening of hip and trunk muscles. Positioning also allows greater interaction with peers and environment.


Scott D. Silver, CO; John R. Fisk, MD, Northwestern University Medical School/Prosthetic-Orthotic Center, 345 East Superior Street, Chicago, IL 60611

After many years of working with patients requiring seating orthoses, better anterior control in seating orthoses is needed. Two case studies assess this need. If the potential of seating orthoses is to be realized with regard to spinal control and/or correction, posteriorly and laterally directed forces upon the body must be analyzed. The cases show the advantages of progressive, aggressive anterior control in a total orthotic seating system.


James H. Campbell, CPO, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44106

This orthosis provides efficient ambulation for the paraplegic child, especially one who presents spinal deformity and hip flexion contracture. The orthosis offers mechanical substitution for weak or paralyzed muscles and restrains the forces of those with unbalanced action. Prescription is based on assessment of neurologic deficit. It has provided efficient ambulation for children whose pathologies include spina bifida with myelodysplasia, neuroblastoma and muscular dystrophy. The orthosis is custom made and includes low friction rollerbearing hip joints linked by a single Bowdenflex push pull linear bearing which is a highly efficient means of joining the hip joints to transmit the forces that assist reciprocal walking. Clinical trials are ongoing at the Department of Orthotics, Cleveland Clinic Foundation. Initial findings indicate that this new design offers distinct advantages over other systems.


Anthony Ballard, MD, University of Miami, Box 016960, D-27, Miami, FL 31101

Excessive internal rotation of the leg results in an uncosmetic gait. This causes considerable concern for patients, family, friends, physicians, and frequently, observing strangers. Multiple treatment methods have been devised, including: observation, manipulation, shoes, appliances, and surgery. Most of these methods take advantage of the naturally-occurring external rotation of the leg segment with time and growth. This presentation will describe the use and results of a 90-degree-angle, flexed-knee, derotation orthosis, designed by Newton C. McCullough, 111, MD, at the University of Miami. Medical records of thirty-one, otherwise normal, ambulatory children, who had complied with the use of this device, were evaluated. Prior to treatment, the average thighfoot angle was minus 25 degrees with a range of minus 20 to minus 45 degrees. At the termination of treatment the average thigh-foot angle was plus 9 degrees with a range from zero to plus 30 degrees. The duration of treatment was 6 months to 48 months with an average of 19 months and a mean of 12 months. No secondary deformities or other complications, secondary to the use of this device, were found. The compliance of patients and parents to the use of this treatment method in our clinic is 75 percent. This orthotic device appears to be effective in correcting the excessive internal rotation of the leg segment.


Robert Kent Ballard, Orthotist, University of Miami, Miami, FL

Many types of orthotic devices have been used to treat children with excessive internal rotation of the leg. Most devices attach to the foot and externally rotate the entire lower limb, including the hip. This presentation will describe a derotation orthosis that concentrates the rotation forces on the leg segment. The orthosis was designed by Newton C. McCollough, III, M.D., and has been utilized in the University of Miami pediatric-orthopaedic clinics for the past eight years. The components, fabrication and fitting of the Miami Derotation Leg Orthosis will be described. The pitfalls and solutions to the effective use of the orthosis will be discussed.


John R. Fisk, MD; Thomas M. Gavin, CO, 8177 South Cass Avenue, Darien, IL 60559

The non-operative treatment of high thoracic scoliosis is controversial and not well covered in the literature. Some claim that orthoses do not work for these curves, while others fit these patients with a CTLSO but do not expect favorable results. An orthotic force system may be used to treat high curves, and may be applied with a CTLSO or a TLSO. The force system is two-fold. First, the auxiliary component of either the shoulder ring or the TLSO structure maximally loads the curve, shifting the trunk to the contralateral side. Then the trapezius aspect depresses the shoulder in a medial position, righting (compensating) the patient thus providing curve endpoint counterforce. This system has yielded up to 50% curve reduction in some patients with high thoracic curves. This method will prevent high thoracic curve progression for some patients who otherwise may not have been successful in an orthosis.


Norman Berger, MS; Joan E. Edelstein, MA, PT, New York University, Prosthetics and Orthotics, 317 East 34th Street, New York, NY 10016

One hundred twenty children with unilateral below-elbow amputations were each provided with a myoelectrically controlled hand (MYO) and a body-powered hand (BP) of identical size, shape, and glove color, as part of a comprehensive field study conducted at eleven units of the Shriners Hospitals for Crippled Children. In one aspect of the study, the children were videotaped as they performed prosthetic prehension tests on a formboard and a series of ten standardized activities requiring bimanual function. Seventy-six pair of tapes were analyzed; excluded were tapes from subjects younger than 6 and those of poor visual quality. Data collected consisted of time and errors (e.g. dropped objects) for the formboard, and time and ratings of performance quality for the activities of daily living. With the MYO hand, children took 14 percent longer to complete the formboard and committed more than twice as many drop and delay errors. Overall performance of practical activities was similar in time and quality regardless of type of hand. Children provided with more training completed the formboard faster and with fewer errors; longer training, however, was not associated with better practical performance. Unimanual formboard prehension tasks appear to place unrealistically high prosthetic demands on the wearer as compared with bimanual practical activities in which the sound side plays the dominant role. Acceptance of the MYO or BP depends primarily on factors other than performance.


Sharon Shapiro, OTR/L; Mary Locast, OTR/L, Shriners Hospital for Crippled Children, 2211 North Oak Park Avenue, Chicago, IL 60635

The voluntary-opening hook terminal device (TD) was compared to the ADEPT voluntary-closing terminal device for children with below-elbow amputations. Comparisons have been made in terms of appearance, precision, spontaneous use, strength of grasp, and overall preference. Subjects have all recently switched to the ADEPT TD from the hook TD. Subjective and objective questionnaires were given to each subject at or near the time they received their ADEPT TD and again at two follow up clinic visits. Videotapes of the subjects performing functional tasks provided objective comparison of TD use. Preliminary findings show that the majority of subjects prefer the ADEPT TD overall to the traditional hook. Several subjects chose to return to using the hook after a short trial with the ADEPT TD because of the stated effort involved in holding objects with the ADEPT TD. Few differences were noted in wearing time of the prosthesis or in need for repair. Results of the study were based on subjective viewing of the videotapes and the stated performance.


Barbara Kaniewski, OTR, Area Child Amputee Center, 235 Wealthy Street, SE, Grand Rapids, MI 49503

Since January 1987 the Area Child Amputee Center has offered a voluntary-closing terminal device to 31 children. Of this group, twenty-eight limbs were fit as below-elbow amputations and four were fit as above-elbow. Children ranged from 2 to 20 years old. Two children were bilateral amputees. The voluntary-closing terminal device was offered to enhance prosthetic use in a borderline user and/or to improve patient and family satisfaction regarding comfort, function, and appearance for those who were already good users. The voluntary-closing terminal device was also offered to selected below-elbow am purees as their first activated prosthesis. Objective measure of pinch ability and subjective reports of patient and family satisfaction will be presented Steps taken by the Center's team to assist in a successful transition to this device, concerns, such as reimbursement from state programs and third-party insurers, as well as cost, will be addressed. Less receptive to the voluntary closing terminal device were adolescents and above-elbow amputees. The voluntary-closing terminal device can be a valuable alternative for the below-elbow amputee.


Arlene Libby, OTR; Sharon Greenberg, MOT; Brian Dudgeon, MS, OTR; Kenneth Jaffe, MD, Children's Hospital and Medical Center, 4800 Sand Point Way NE, PO Box C5371, Seattle, WA 98105

Voluntary-opening and voluntary-closing terminal devices offer different functional options for limb-deficient children. This case report describes a 5 year old boy with a transverse below-elbow deficiency who was switched from voluntary-opening to a voluntary-closing terminal device. He had been a full time CAPP terminal device user when his parents were concerned by his lac of spontaneous prehension and his difficulty with sustained grip. Other prosthetic options, including a voluntary-opening hook and myoelectric hand, were considered before a voluntary-closing terminal device was prescribed. The child's early prosthetic management, factors considered by the treatment team, family and patient in making the switch, initial prosthetic training follow-up home program, and the current functional status after two years wit the voluntary-closing terminal device will be discussed.


Roberta Kuchler-O'Shea; Barbara Baldassare; Tracy Tollefson, La Rabid Children's Hospital and Research Center, East 65th Street at Lake Michigan Chicago, IL 60649

Reports of management of quadrimembral amputees in the literature are rare and even more so in the case of an acquired quadrimembral amputation in a child. This case study is a follow-up presentation of a 5 year-old child originally reported at age 2. This child has made tremendous functional gains. Wit continued therapy and prosthetic management, he is independent with house hold ambulation and most basic self-care. He attends school full-time and ca complete age-appropriate skills independently. His current prosthetic use an functional abilities will be demonstrated in a video tape presentation.


Robin C. Crandall, MD; Donabelle Hansen, RPT, Shriners Hospital for Crippled Children, 8290 University Avenue, Fridley, MN 55432

Twenty patients at the Minneapolis Shriners Hospital with forearm amputations were randomly converted to a voluntary-closing terminal device. The basic criteria for patient selection included full-time usage of a body-powered below-elbow prosthesis. The minimum usage was 80 hours. All patients were shown videotapes of the prosthetic device and its use. Education pertaining to it was conducted by physical therapy and clinic personnel. Clinical and patient questionnaire evaluations were done at 6 month intervals. The patient group consisted of 11 boys and 9 girls with an average age of 9.5 years. Nineteen patients had congenital amputations, I was traumatic. Patients had worn voluntary-opening designs for an average of 8.9 years. No patients who were actively using myoelectric units were included in the study. The voluntary-closing terminal device was highly preferred by 16 patients who refused to return to the voluntary-opening design. Rejection occurred in older individuals who had difficulty adjusting to the new design.


M. Mifsud, E.Eng.T; S. Hubbard, P and OT BSc; G. Verburg, MA; S. Naumann, PhD. P.Eng.; H. R. Galway, MD, FRCS(C); M. Milner, PhD. P.Eng. CCE, The Hugh MacMillan Medical Centre, 350 Rumsey Road, Toronto, Ontario M4G 1R8 Canada

Our current research, ending July 1989, has been directed at developing objective methods relating to the fitting and application of myoelectric control systems. Twenty experienced below-elbow amputees requiring a socket replacement are being fitting using both a newly developed microcomputer-based system and traditional procedures for comparison. The newly developed HHMC MYOELECTRIC ASSESSMENT SYSTEM encompasses tools for objective:

  • finding the most appropriate muscle sites;
  • determining the amputee's suitability to a class of control systems;
  • determining controlling myoelectric signal levels with the socket donned and weighted;
  • determining signal variations produced during sustained muscle contractions and in various forearm positions;
  • determining antagonist muscle signal cross-talk and non-voluntary co-contraction signals in order to minimize inadvertent activation of the prosthesis;
  • using the calculated calibration levels to calibrate the myoelectric control system; and
  • checking and verifying calibration of the control system during follow-up visits and when service is required.

The system allows the clinician to verify visually the calibration levels with consideration given to the rate of change of the measured myoelectric signals as well as allowing for manual adjustment of the calibration levels, if necessary. The system is a general myoelectric tool that may be used with many control systems. This is a viable and valuable product for all clinics, a tool that can be cost-effectively expanded for newer technologies.


John C. Wood; Daniel T. Barry; Beth Alter; Mary Amann; Linda Minor, University of Michigan Occupational Therapy, Ann Arbor, MI 48109

Acoustic signals from muscle were used to control upper-extremity prostheses in individuals who had difficulty operating a conventional myoelectric device because of extensive scar tissue from bums or trauma. A two microphone differential control system was designed and its performance compared to an Otto-Bock myoelectric prosthesis. Three upper-extremity amputees were tested, two of whom had significant scarring and difficult myoelectric site selection. A modified subset of the Smith hand function test was used to compare the two technologies. The myoacoustic device worked nearly as well as the myoelectric for the individual who had no scarring. The two individuals with scar tissue, however, had such severe muscular co-contraction that a differential acoustic signal was not attainable. This -suggests that the difficulty that these amputees had in operating the myoelectric device was not from poor conduction of the myoelectric signal through the skin, as was hypothesized, but rather from poor muscular isolation. This study indicates that while myoacoustic control is a viable alternative to myoelectric control, it may not benefit those patients who are unable to use a myoelectric device.


Diane B. Patterson, LOTR; Patsy McMillan, LOTR; Raoul Rodriguez, MD Children's Hospital of New Orleans, New Orleans, LA

The acceptance rate of myoelectric prostheses by 18 children fitted with myoelectric prostheses at Children's Hospital over the past seven years was assessed. The study includes children with above-elbow and below-elbow, acquired and congenital limb deficiencies. An overview of the successful prosthetic program at Children's Hospital will be presented from both the physician's and therapist's perspectives. Several factors contribute to the more than 83% acceptance rate, including age of fitting, prior experience with body-powered prostheses, influence of contact with other limb-deficient children and degree of parental involvement. Acceptance depends on the amount of follow-up therapy. Indications for initially fitting a child will be discussed.


Ramona M. Okumura, CP, Gillette Children's Hospital, 200 East University, Saint Paul, MN 55101

Sara is a 13 year old girl with a T-11 level sacral agenesis. An overview of her surgical and prosthetic treatment will be given with a focus on the team approach. The emphasis is on meeting the short term needs keeping the long term functional goals in mind and matching them with medical expertise and technology. High technology is not always equivalent to increased function and rehabilitation of the total child.


David Lyttle, MD, FRCSC; William Nichol, CPO; Paul Osborne, Rehabilitation Centre for Children, 800 Sherbrook Street, Winnipeg, Manitoba R3A I M4 Canada

Upper-limb prostheses designed and fitted to young people in many parts of Canada are expected to function outdoors during conditions of summer heat up to 40 degrees C and winter cold down to - 40 degrees C. Many factors must be considered when prescribing and fitting the socket. Exposure of the skin to cold mandates against fenestration of the socket. Insulation of the socket wall is important, particularly in myoelectric fittings where socks cannot be worn. Some types of laminate, even when reinforced with carbon fibre become very brittle and crack readily at low temperatures. Batteries operating at low temperature produce lower voltage and require more frequent recharging because greater currents are required to drive the motors; the viscoelasticity of prosthetic gloves is markedly altered. Prosthetic design is aimed at proximal placement of batteries to allow body heat to keep them warm. Variation in speed of response for opening and closing of a two-state myoelectric prosthesis demonstrates that at extremes of cold such limbs become useless. The response characteristics of an electro-mechanical servocontrol mechanism was also studied. At low temperatures the control mechanism first becomes an all-ornone control and then fails entirely. The lack of control of such prostheses in the cold is a serious safety consideration. Body-powered prostheses are more reliable and less hazardous under such circumstances.


Craig W. Heckathorne, MSEE; Harold Crisk, CP; Jack Uellendahl, CPO; Yeongchi Wu, MD, Rehabilitation Institute of Chicago, 345 East Superior Street, Chicago, IL 60611.

The prosthetics team of the Rehabilitation Institute of Chicago has been developing and applying concepts for fitting cable-operated arm prostheses for adults based on ideas of George Robinson and Jim Caywood of Robin Aids. These concepts center on the use of positive-locking wrist components-for flexion/extension and rotation-and positioning of the components using the same control cable utilized for elbow flexion and split hook opening. This arrangement provides for great variation and relative ease in orienting the prehensor, feedback of the movements of and forces on the controlled component, and rigidity against displacement (when the components are locked) due to forces associated with the use of the prosthesis. During the past three years, multifunction positive-locking prosthetic systems have been developed for adults with bilateral amputations at the below-elbow, above-elbow, and shoulder-disarticulation levels. These systems have recently been adapted to children in conjunction with a Project Hope initiative to provide prostheses to children who lost limbs in the 1988 Armenian earthquake. Selection of components and modifications made to them to accommodate the size, force, and excursion limits of children will be discussed in the context of fitting three children with bilateral upper-limb amputations.


Eugene Danzinger, CP; R. D. Beauchamp, MD, FRCS (C), 650 West 41st, #210, Oakridge Centre, Vancouver, British Columbia V5Z 2M9, Canada

Prenatal diagnosis predicted of a child eventually born with a complete upperlimb amelia. A 7 month-old girl appears to be an identical twin. Her sister seems normal in all respects. We designed a prosthesis which provided comfort, light weight, passive function, good appearance, ease of adjustability for growth, and low maintenance. An endoskeletal prosthesis was fabricated with a shoulder cap socket incorporating passive shoulder flexion and extension, humeral rotation and a hand with a glove. Readily available materials have been utilized. A conventional foam cover and flesh colored stockinette improved appearance. The patient accepted the prosthesis well. Functional aspects of the appliance were very gratifying. By appropriate counselling and parental education, the circumstances surrounding the birth of a limb-deficient infant can be accepted by the parents much more easily.


Charles J. Courtney, CO, D. C. Crippled Children's Clinic, Stephen S. Dillon, EE, Universal Artificial Limb Co., 938 Wayne Avenue, Silver Spring, MD 20910

A 9 month-old female bilateral amelic was presented at clinic and a unilateral fitting was prescribed with articulation of the shoulder, humeral and elbow joints and a powered hand. Search of manufacturer's literature from the United States, Canada and Europe confirmed that suitable shoulder componentry did not exist. A low-profile (thickness-0.380") adjustable friction rotation joint was designed and built. A Steeper infant elbow/humeral joint was modified to permit internal passage of the electrical cable to the hand. The hand itself was a VVO-3A from Variety Ability Systems. A single-function voluntary-opening control system and miniature battery pack were designed to fit in the humeral shell. The control system is activated by a 0.017" thick pressure sensor located in the shoulder cap above the acromion. A second control site was provided on the exterior of the shoulder cap to permit the parent or therapist to activate the hand. The finished prosthesis is completely self-contained and weighs one pound. Details of the shoulder joint, modifications to the elbow and the control/battery system will be presented.


Michael Moor, CPO; Richard Psonak, CP, Newington Children's Hospital, 181 East Cedar Street, Newington, CT 06111

With the advent of new technologies and materials, the below-elbow child amputee is being fit with a more sophisticated prosthesis at an earlier age than ever before. The greatest challenge to the prosthesist is that of providing a total contact, intimate socket for a rapidly growing child. At Newington Children's Hospital we custom-make an adjustable, overlap socket that allows for growth in girth and length. A practical method for fabricating and fitting this socket for the below-elbow child amputee is outlined. This method has several possible applications for above-elbow and below-knee amputees as well.