DOH Prosthetist & Orthotist oral exam prep

Knowledge: Residual limb volume falls over the first months as oedema settles, so a socket cast early becomes loose and the patient adds socks. Too many socks distort the socket shape, let the limb sink and piston, and load the pressure-sensitive areas, chiefly the tibial crest, distal tibia and fibular head, rather than the pressure-tolerant patellar tendon, medial tibial flare and pretibial muscles. A distal tibial wound is therefore a fit problem. A pin that does not engage fully adds pistoning. In a man with diabetes and possible neuropathy, a small wound can become infected and threaten the limb.

Management: Today I would measure and photograph the wound with consent, look for spreading redness, discharge or fever, and check his other foot. I would advise him to stop using the prosthesis until the wound is reviewed, and refer him to the rehabilitation physician and wound team, the same day if infection is suspected. I would check sock ply, pistoning, pin engagement and alignment. I would not simply grind the socket over the wound. Once the wound has healed and volume is stable, he needs a new socket, often a test socket first. I would teach daily mirror skin checks, sock management and shrinker use. I would review him within a week.

Ethics and communication: I would explain honestly that the socket no longer fits his changing limb and that pausing use protects the limb, even though he wants to keep walking and working. Wound and infection treatment belong to the physician, so I refer rather than manage them myself. I would document findings, advice and his understanding, and agree a plan with him and, if he wishes, his family.

Reference: Lusardi, Jorge and Nielsen, Orthotics and Prosthetics in Rehabilitation; IWGDF Guidelines on the prevention and management of diabetes-related foot disease (2023)

Knowledge: A warm, red, swollen foot in a person with neuropathy, without an ulcer, is active Charcot neuro-osteoarthropathy until proven otherwise. A side-to-side temperature difference of more than about 2 degrees C supports activity, and absence of pain is typical because of neuropathy. A normal X-ray does not exclude it, because early disease may show only bone marrow oedema on MRI. Differentials include cellulitis, osteomyelitis, gout and deep vein thrombosis. Untreated, the midfoot can collapse into a rocker-bottom deformity, ulcerate and lead to amputation. The IWGDF guidance treats active Charcot with immediate knee-high offloading, preferably a non-removable device such as a total contact cast, not insoles.

Management: I would not make insoles today. I would contact the referring physician or diabetic foot team the same day, explain my findings and recommend urgent assessment, including MRI if they decide. Until she is seen, I would advise her to limit walking and standing on the foot. If the team confirms active disease, I would provide or support the knee-high offloading they prescribe, either a total contact cast applied by trained staff or a knee-high walker made non-removable. I would measure skin temperature at each review as a guide to activity. Once the team judges remission, she moves to a removable device, then a Charcot restraint orthotic walker or custom footwear with total contact insoles for life. I would examine the other foot and teach daily foot checks.

Ethics and communication: Diagnosis belongs to the physician, so my role is to recognise the problem and refer clearly rather than fill the prescription as written. I would explain why insoles could harm her and what months of offloading involve, including effects on work and family duties. If she declines a non-removable device, I would document the advice and inform the team.

Reference: IWGDF Guidelines on the prevention and management of diabetes-related foot disease (2023); Rogers et al, The Charcot foot in diabetes (Diabetes Care 2011)

Knowledge: She is at high risk of progression: she is skeletally immature at Risser 0, premenarchal, and has a curve in the 25 to 40 degree range usually treated with bracing. The BrAIST trial (Weinstein, NEJM 2013) found that bracing reduced progression to the surgical range, with success in 72 percent of braced patients against 48 percent observed, and that longer daily wear was linked to better outcomes. SOSORT guidance supports full-time bracing for curves like hers. Night-time braces have weaker evidence, so changing the regimen is the surgeon's decision. A good in-brace correction on X-ray predicts success, and comfort and appearance drive adherence.

Management: I would explain the evidence and wear-time effect in plain words and pass the night-time request to the surgeon rather than agree to it myself. I would scan or cast, build the brace with pads over the apex, and check trimlines for sitting, axillae and the pelvis at a trial fit. The surgeon arranges an in-brace X-ray to confirm correction. I would build up wear time over one to two weeks, with a cotton vest under the brace, daily skin checks, and advice on heat and hydration. I would offer a school letter about sports and changing. I would review her at four to six weeks, then regularly as she grows, and adjust or replace the brace. Persistent redness or skin breakdown means she contacts me early.

Ethics and communication: Under UAE law her guardian consents, but I would seek her own agreement and listen to her concerns about body image, which predict adherence. I would offer a female practitioner or chaperone for fitting. I would be honest that the brace aims to prevent progression, not straighten the spine fully. I would document the discussion and share it with the surgeon.

Reference: Weinstein et al, Effects of bracing in adolescents with idiopathic scoliosis (N Engl J Med 2013); SOSORT 2016 guidelines on orthopaedic and rehabilitation treatment of idiopathic scoliosis (Negrini et al, Scoliosis Spinal Disord 2018)

Knowledge: Redness lasting more than about 20 to 30 minutes after removal shows excessive pressure. A heel blister suggests the heel is not seated, often because the orthosis is set at more dorsiflexion than the calf allows, so the heel lifts and rubs. With only 0 degrees of dorsiflexion with the knee extended, a solid orthosis set at 90 degrees may push the knee into hyperextension or cause heel lift. Botulinum toxin usually wears off over about three to four months, so tightness may be returning. Tuning the orthosis and shoe combination so the shank is inclined forward by about 10 to 12 degrees in mid-stance improves knee and hip mechanics. Children may not report discomfort clearly.

Management: I would stop wear on the left until the blister heals and check both feet. I would assess the fit: relieve the navicular, improve heel seating with a well-placed ankle strap, and check the ankle angle against his available range. I would observe and video his gait and tune the orthosis with heel wedges in his shoes. I would contact his physiotherapist and rehabilitation physician, because serial casting, stretching or further toxin may be needed before the orthosis can be set correctly; that decision is theirs. I would rebuild wear time gradually and teach the father skin checks. I would review him in one to two weeks, and sooner if new redness appears.

Ethics and communication: His guardian consents, but I would involve the boy, because his refusal is a message about comfort. I would tell the father honestly that the blister is device-related, document it and report it through the facility incident system. Good communication within the team prevents the family receiving mixed messages.

Reference: NICE NG62 Cerebral palsy in under 25s: assessment and management (2017); Owen, The importance of being earnest about shank and thigh kinematics especially when using ankle-foot orthoses (Prosthet Orthot Int 2010)

Knowledge: Headache and vomiting after a head injury need medical assessment, and whether he needs imaging under head injury guidance is the doctor's decision, not mine. Mechanically, loose pyramid set screws let the alignment shift and can lead to sudden failure; manufacturers specify torque values and thread-locker. Stance stability depends on alignment and on the knee unit, and ramps demand the most stability. The device is evidence and must be examined as found. Other limbs assembled by the same process may carry the same fault.

Management: Immediately I would make sure he is safe and arrange same-day medical review in the emergency department. He should not walk on the limb. I would photograph the device, record what is loose, and quarantine it without tightening anything. I would inform my supervisor and complete an incident report. If a component fault is suspected, I would notify the manufacturer and follow facility policy on device reporting. Once he is cleared, the limb is reassembled with the specified torque and thread-locker, and alignment is checked on the bench, static and dynamic. Ramp training with the physiotherapist follows. I would check other recent limbs assembled by the same process.

Ethics and communication: He deserves an honest explanation that a fitting fault probably contributed, with an apology, given in line with UAE law and facility policy. I would not blame my colleague in front of him; the review should look at the process, such as a second check before delivery. I would document facts, times and advice carefully. Medical liability under Federal Decree-Law No. 4 of 2016 is a reason for accurate records, not for silence.

Reference: ISO 10328:2016 Prosthetics, structural testing of lower-limb prostheses; NICE NG232 Head injury: assessment and early management (2023); WHO Standards for Prosthetics and Orthotics (2017)

Knowledge: Prescription should match functional level. The Medicare Functional Classification Levels run from K0 to K4, and an indoor walker with a frame and a Timed Up and Go of 28 seconds is likely K1 to K2. Energy-storing carbon feet are designed for K3 to K4 users who walk at varied speeds; for a low-mobility user they can feel stiff, give little benefit and may reduce stability. A solid ankle cushion heel or simple multiaxial foot often suits him better. A standardised tool such as the Amputee Mobility Predictor makes the decision transparent. Gifts from suppliers create a conflict of interest that can bias prescribing.

Management: I would decline the trip, or declare it to my manager and follow the facility conflict-of-interest policy, and accept no personal benefit. For the patient, I would assess him with the physiotherapist and physician, use the Amputee Mobility Predictor, and set realistic goals. I would explain to him and his son, in plain words, why a stiffer energy-storing foot may not help and may make him less steady. I would offer a foot that suits his current function and plan review in four to six weeks, with an upgrade if his mobility improves. I would agree the choice with the rehabilitation team so the prescription reflects a shared assessment. I would document the assessment, the options discussed and the reasons for my choice.

Ethics and communication: The patient, not the son, makes the decision if he has capacity, although in GCC families relatives are often closely involved and should be welcomed. Honest advice protects him from a device that could increase his falls risk, and protects the family from spending money with little benefit. Transparency about any industry contact keeps patients' trust.

Reference: Gailey et al, The Amputee Mobility Predictor (Arch Phys Med Rehabil 2002); WHO Standards for Prosthetics and Orthotics (2017)