Project description:BackgroundThe suction sockets that are commonly prescribed for transtibial amputees are believed to provide a better suspension than the pin/lock systems. Nevertheless, their effect on amputees' gait performance has not yet been fully investigated. The main intention of this study was to understand the potential effects of the Seal-in (suction) and the Dermo (pin/lock) suspension systems on amputees' gait performance.Methodology/principal findingsTen unilateral transtibial amputees participated in this prospective study, and two prostheses were fabricated for each of them. A three-dimensional motion analysis system was used to evaluate the temporal-spatial, kinematics and kinetics variables during normal walking. We also asked the participants to complete some part of Prosthesis Evaluation Questionnaire (PEQ) regarding their satisfaction and problems with both systems. The results revealed that there was more symmetry in temporal-spatial parameters between the prosthetic and sound limbs using the suction system. However, the difference between two systems was not significant (p<0.05). Evaluation of kinetic data and the subjects' feedback showed that the participants had more confidence using the suction socket and the sockets were more fit for walking. Nevertheless, the participants had more complaints with this system due to the difficulty in donning and doffing.ConclusionIt can be concluded that even though the suction socket could create better suspension, fit, and gait performance, overall satisfaction was higher with the pin/lock system due to easy donning and doffing of the prosthesis.Trial registrationirct.ir IRCT2014012816395N1.
Project description:BackgroundLoss of residual limb volume degrades socket fit and may require accommodation.ObjectivesTo examine if either of two accommodation strategies executed during resting, socket release with full socket size return and socket release with partial socket size return, enhanced limb fluid volume retention during subsequent activity.Study designTwo repeated-measures experiments were conducted to assess the effects of socket release on limb fluid volume retention.MethodsLimb fluid volume was monitored while participants wore a socket with a single adjustable panel. Participants performed eight activity cycles that each included 10 min of sitting and 2 min of walking. The socket's posterior panel and pin lock were released during the fifth cycle while participants were sitting. In one experiment (Full Return), the socket was returned to its pre-release size; in a second experiment (Partial Return), it was returned to 102% of its pre-release size. Short-term and long-term limb fluid volume retention were calculated and compared to a projected, No Intervention condition.ResultsPartial Return and Full Return short-term retentions and Partial Return long-term retention were greater than those projected under the control condition ( p < 0.05).ConclusionSocket release during resting after activity, particularly when the socket is returned to a slightly larger size, may be an effective accommodation strategy to reduce fluid volume loss in transtibial prosthesis users.Clinical relevanceThis study suggests that existing prosthetic technologies' adjustable sockets and locking pin tethers can be used in novel ways to help maintain residual limb fluid volume in active prosthesis users.
Project description:BackgroundStep activity monitors provide insight into the amount of physical activity prosthesis users conduct but not how they use their prosthesis. The purpose of this research was to help fill this void by developing and testing a technology to monitor bodily position and type of activity.MethodsThin inductive distance sensors were adhered to the insides of sockets of a small group of transtibial prosthesis users, two at proximal locations and two at distal locations. An in-lab structured protocol and a semi-structured out-of-lab protocol were video recorded, and then participants wore the sensing system for up to 7 days. A data processing algorithm was developed to identify sit, seated shift, stand, standing weight-shift, walk, partial doff, and non-use. Sensed distance data from the structured and semi-structured protocols were compared against the video data to characterize accuracy. Bodily positions and activities during take-home testing were tabulated to characterize participants' use of the prosthesis.FindingsSit and walk detection accuracies were above 95% for all four participants tested. Stand detection accuracy was above 90% for three participants and 62.5% for one participant. The reduced accuracy may have been due to limited stand data from that participant. Step count was not proportional to active use time (sum of stand, walk, and standing weight-shift times).InterpretationStep count may provide an incomplete picture of prosthesis use. Larger studies should be pursued to investigate how bodily position and type of activity may facilitate clinical decision-making and improve the lives of people with lower limb amputation.
Project description:This descriptive study aimed to compare the magnetic resonance appearance of the distal interphalangeal joint articular cartilage between standing weight-bearing and non-weight-bearing conditions. Ten forefeet of live horses were scanned in a standing low-field magnetic resonance system (0.27 T). After euthanasia for reasons unrelated to the study, the non-weight-bearing isolated feet were scanned in a vertical positioning reproducing limb orientation in live horses. The same acquisition settings as during the weight-bearing examination were used. Thickness and cross-sectional area of the distal interphalangeal articular cartilage and joint space were measured on tridimensional T1-weighted gradient echo high resolution frontal and sagittal images at predetermined landmarks in both conditions and were compared using a linear mixed-effects model. Frontal images were randomized and submitted to 9 blinded readers with 3 different experience levels for identification of weight-bearing versus non-weight-bearing acquisitions based on cartilage appearance. Weight-bearing limbs had significantly thinner distal interphalangeal cartilage (p = 0.0001) than non-weight-bearing limbs. This change was greater in the distal phalanx cartilage than that of the middle phalanx. Blinded readers correctly identified 83% (range 65 to 95%) of the images as weight-bearing or non-weight-bearing acquisitions, with significantly different results observed among the different readers (p < 0.001) and groups (p < 0.001). These results indicate that distal interphalangeal articular cartilage and particularly cartilage of the distal phalanx thins when weight-bearing compared to the non-weight-bearing standing postmortem conditions and suggest that cartilage abnormalities may be more difficult to identify on weight-bearing standing magnetic resonance imaging.
Project description:BackgroundThere exists a need for an adjustable socket to accommodate residual limb volume and shape changes. Further, limb loss rates globally are rising and there is a large unmet need for affordable and accessible prosthetic systems.ObjectiveTo assess the utility of an immediate fit modular prosthetic system (iFIT Prosthetics, LLC).DesignProspective feasibility study involving a 2-week single-group pre-post intervention study.SettingPhysical Medicine and Rehabilitation gait laboratory.ParticipantsParticipants were at least 6 months post amputation and walking with a conventional prosthesis. They were free of skin wounds, other neurological disorders, and severe pain conditions.MethodsParticipants were fit with an immediate fit prosthesis and instructed to wear it for a 2-week evaluation period. They were given a progressive wearing schedule and they completed outcome measurements at the 2-week follow-up.Main outcome measurementsSelf-reported satisfaction, gait biomechanics, and intrasocket peak pressures.ResultsTwenty-six participants entered the study, with 22 completing the single group pre-post study. They averaged 50 years (SD ±10.2) of age; four were female. Sixteen were dysvascular and 10 were traumatic in etiology. Significant differences (P = .03) in self-reported satisfaction were found in favor of the iFIT device 29.33 (SD ± 4.51) versus the conventional device 25.52 (SD ± 6.8). No falls or limb ischemia were reported. Gait biomechanics revealed no differences across any temporal characteristics. Intrasocket peak pressures were significantly lower for the iFIT prostheses overall (P = .0014), at the anterior tibia (P = .0002), and the lateral side of the residual limb (P = .013).ConclusionsThe iFIT transtibial prosthetic system appears to be safe in this short-term single-group pre-post study. This study provided preliminary evidence to support the feasibility of the iFIT system. It compared favorably to participants' conventional prostheses across all outcome measures. With its cost, adjustability, and accessibility advantages, this device may prove useful for persons with transtibial amputations. A larger multicenter study is needed to confirm these results.Level of evidenceIII.
Project description:UNLABELLED: Anterior knee pain is one of the major short-term complaints after TKA. Since the introduction of the mobile-bearing TKA, numerous studies have attempted to confirm the theoretical advantages of a mobile-bearing TKA over a fixed-bearing TKA but most show little or no actual benefits. The concept of self-alignment for the mobile bearing suggests the posterior-stabilized mobile-bearing TKA would provide a lower incidence of anterior knee pain compared with a fixed-bearing TKA. We therefore asked whether the posterior-stabilized mobile-bearing knee would in fact reduce anterior knee pain. We randomized 103 patients scheduled for cemented three-component TKA for osteoarthrosis in a prospective, double-blind clinical trial. With a 1-year followup, more patients experienced persistent anterior knee pain in the posterior-stabilized fixed-bearing group (10 of 53, 18.9%) than in the posterior-stabilized mobile-bearing group (two of 47, 4.3%). No differences were observed for range of motion, visual analog scale for pain, Oxford 12-item questionnaire, SF-36, or the American Knee Society score. The posterior-stabilized mobile-bearing knee therefore seems to provide a short-term advantage compared with the posterior-stabilized fixed-bearing knee. LEVEL OF EVIDENCE: Level I, therapeutic study.
Project description:Prosthetic suspension system is an important component of lower limb prostheses. Suspension efficiency can be best evaluated during one of the vital activities of daily living, i.e. walking. A new magnetic prosthetic suspension system has been developed, but its effects on gait biomechanics have not been studied. This study aimed to explore the effect of suspension type on kinetic and kinematic gait parameters during level walking with the new suspension system as well as two other commonly used systems (the Seal-In and pin/lock). Thirteen persons with transtibial amputation participated in this study. A Vicon motion system (six cameras, two force platforms) was utilized to obtain gait kinetic and kinematic variables, as well as pistoning within the prosthetic socket. The gait deviation index was also calculated based on the kinematic data. The findings indicated significant difference in the pistoning values among the three suspension systems. The Seal-In system resulted in the least pistoning compared with the other two systems. Several kinetic and kinematic variables were also affected by the suspension type. The ground reaction force data showed that lower load was applied to the limb joints with the magnetic suspension system compared with the pin/lock suspension. The gait deviation index showed significant deviation from the normal with all the systems, but the systems did not differ significantly. Main significant effects of the suspension type were seen in the GRF (vertical and fore-aft), knee and ankle angles. The new magnetic suspension system showed comparable effects in the remaining kinetic and kinematic gait parameters to the other studied systems. This study may have implications on the selection of suspension systems for transtibial prostheses. Trial registration: Iranian Registry of Clinical Trials IRCT2013061813706N1.
Project description:ObjectivesThis study aims to investigate cross-sectional area of the amputated-limb rectus femoris compared to the intact-limb and controls and to determine its correlation with functional strength and walking tests in prosthesis users with transtibial amputation.Patients and methodsBetween October 2018 and April 2019, a total of 14 prosthesis users (12 males, 2 females; mean age: 47.1±16.2 years; range, 26 to 73 years) who met the inclusion criteria, and 14 age-, sex-, and dominancy-matched able-bodied controls (12 males, 2 females; mean age: 47.1±16.2 years; range, 26 to 73 years) were included in this case-control study. Cross-sectional area of rectus femoris (CSA-RF) was evaluated bilaterally by two independent examiners. Knee extension strength was measured bilaterally by using a handheld dynamometer. Functional strength and walking were assessed by Step-Up-Over and Walk-Across tests of the NeuroCom Balance Master® device.ResultsThe CSA-RF was found to be reduced in amputated-limb compared to the intact-limb and able-bodied controls (p<0.01). In the prosthesis users, the cross-sectional area difference between both limbs rectus femoris muscles was shown to be correlated with actual and functional knee extension strength, step length, and walking speed (p<0.05). Intra- and inter-observer reliability of CSA-RF on both sides were found to be good to excellent (intraclass correlation coefficient: 0.856-0.936).ConclusionUltrasonographic measurement of CSA-RF is a valid and reliable tool to assess the functional strength and walking in the prosthesis users with unilateral transtibial amputation.
Project description:BackgroundIn the modern western world appraisal of economical points such as treatment and disability after trauma present a financial burden. In this context open reduction internal fixation techniques allowing for early full weight bearing might not only improve the clinical outcome but also shorten the period of disability in working life. The aim of the study was to analyze whether ORIF of ankle fractures using either a standard semitubular plate or a new polyaxial locking plate system result in a better clinical outcome.MethodsIn this prospective study, all patients with distal fibula fractures (AO 44 B1.1, B1.2, B1.3), with indication for surgery were included. Patients were randomized to either the DePuy Synthes® one-third semitubular plate (Group I) or NEWCLIP TECHNICS, Active Ankle® polyaxial locking plate (Group II). Primary outcome parameter was function of the ankle joint, assessed by the Olerud and Molander ankle score, Foot and Ankle outcome score and Karlsson and Peterson Scoring System for Ankle function. Secondary outcome parameter were postoperative complications. Superficial wound infection, delayed wound healing, mechanically prominent implant, skin irritations were considered as minor and deep wound infection, material loosening, loss of reduction were regarded as major complications requiring revision surgery. Clinical and radiological follow-up were performed 6 and 12 weeks, 6 months and 1 year postoperatively.ResultsFifty-two patients (31 W/21 M) with a mean age of 43 yrs. (range 22-64 yrs.) were enrolled. Seven patients (13.5%) were excluded, so that 45 patients were available for follow up. Twenty-five patients were treated with DePuy Synthes® one-third semitubular plate (55.6%; group I) while 20 patients received an anatomically preformed polyaxial locking plate (44.4%, group II). Four minor complications occurred in Group I (16%) compared to two minor complications in group II (10%). Significant better clinical results regarding OMAS (p < 0.02, < 0.04), KPSS (p < 0.04) and FAOS (p < 0.02, < 0.03) were observed 6 and 12 weeks after surgery in group II.ConclusionsThe results of the presented study demonstrate a significant better clinical functional outcome in the early postoperative follow-up in patients treated with a polyaxial locking plate. Furthermore, our data show that ORIF using polyaxial locking plates in combination with an early postoperative weight bearing presents a safe, stable treatment option for ankle fractures so that patients benefit especially in the early stages of recovery.Trial registrationRegistered 20 April 2020, retrospectively on ClinicalTrails.gov ( NCT04370561 ).
Project description:Lower-limb prosthesis design and manufacturing still rely mostly on the workshop process of trial-and-error using expensive unrecyclable composite materials, resulting in time-consuming, material-wasting, and, ultimately, expensive prostheses. Therefore, we investigated the possibility of utilizing Fused Deposition Modeling 3D-printing technology with inexpensive bio-based and bio-degradable Polylactic Acid (PLA) material for prosthesis socket development and manufacturing. The safety and stability of the proposed 3D-printed PLA socket were analyzed using a recently developed generic transtibial numeric model, with boundary conditions of donning and newly developed realistic gait cycle phases of a heel strike and forefoot loading according to ISO 10328. The material properties of the 3D-printed PLA were determined using uniaxial tensile and compression tests on transverse and longitudinal samples. Numerical simulations with all boundary conditions were performed for the 3D-printed PLA and traditional polystyrene check and definitive composite socket. The results showed that the 3D-printed PLA socket withstands the occurring von-Mises stresses of 5.4 MPa and 10.8 MPa under heel strike and push-off gait conditions, respectively. Furthermore, the maximum deformations observed in the 3D-printed PLA socket of 0.74 mm and 2.66 mm were similar to the check socket deformations of 0.67 mm and 2.52 mm during heel strike and push-off, respectively, hence providing the same stability for the amputees. We have shown that an inexpensive, bio-based, and bio-degradable PLA material can be considered for manufacturing the lower-limb prosthesis, resulting in an environmentally friendly and inexpensive solution.