An Inexpensive Weight Bearing Indicator With Load Range Capability for Rehabilitation of Patients With Lower Extremity Injuries

This paper investigates the mechanical behavior and design of a patent pending device called a load range weight bearing indicator (LWBI), which provides upper and lower range indication to patients with lower extremity injuries as part of a partial weight bearing rehabilitation. The LWBI consists of two opposing stacks (a.k.a. double stack) of snap domes—bistable mechanical elements that snap through only when a threshold weight is applied—sandwiched between a load transfer plate and base plate. The mechanical behavior of a LWBI has been characterized by testing single and double stacks of snap domes in a rigid aluminum fixture using a universal testing machine. Single stacks of two to eight snap domes each exhibited very predictable and repeatable buckling behavior (i.e., stack buckling load is simply the sum of individual snap dome buckling loads) when deflected at speeds typical for patients walking with a regular gait. The double stack configuration only works when supporting legs of the opposing snap dome stacks are offset by half the angle between adjacent legs. The lower load stack buckles first, while the higher load stack buckles at its threshold load because of the very low force required to keep the lower load stack collapsed. While the presence of a spacer has little effect on the double stack buckling behavior under controlled rate deflection in a precision test fixture, it was required for proper functioning of a LWBI prototype probably because of looser dimensional tolerances. The type of substrate that snap dome stacks are in contact with has little effect on the buckling loads as long as the material is not too soft. Finally, the speed of deflection within the expected range of ambulating patients has an insignificant effect on the LWBI’s buckling behavior. A LWBI prototype was designed based on the observed characteristics of the snap dome double stack with a spacer plate between the upper and lower load stacks. The prototype was installed in a recess in the insole of a biomechanical shoe beneath the patient’s heel. The shoe with LWBI was tested by various subjects pushing on a force plate and the upper and lower buckling loads were clearly indicated to the subject by audible and tactile click and measured as ground reaction force versus time. Future work will focus on further testing of the device and refinement of the design for various medical appliances.

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Progress on Clinical Trials and Product Development of a Simple, Inexpensive Feedback Device for Patients Requiring Partial Weight Bearing

Journal of Medical Devices ◽

10.1115/1.2936203 ◽

2008 ◽

Vol 2 (2) ◽

Author(s):

Daniel Walczyk ◽

Nathaniel Ordway ◽

Kenneth Mann ◽

William Ziomek

Keyword(s):

Clinical Trials ◽

Weight Bearing ◽

Standard Of Care ◽

Verbal Instruction ◽

Partial Weight Bearing ◽

Load Range ◽

Lower Extremity Injuries ◽

Scale Method ◽

Extremity Injuries ◽

Partial Weight

A weight bearing indicator (WBI) has been developed and is undergoing clinical trials and commercialization. The most recent version of the device includes load range indication ability. The WBI is installed in a patient’s medical appliance (e.g. cam walker boot, surgical shoe) and allows patients recovering from lower extremity injuries to self monitor their rehabilitation. It is a simple and inexpensive mechanical device that utilizes the reversible buckling phenomena of a snap dome to provide a tactile ‘click’ and an audible ‘snap’ when a specified ground load on the bottom of a patient’s foot, which has been prescribed by an orthopedist or podiatrist as the partial weight bearing (PWB) upper limit, has been met or exceeded. A clinical study involving 20 subjects showed that PWB compliance improved when comparing the WBI device to standard of care approaches such as verbal instruction and the weight scale method. Specifically, PWB compliance improved from 58% and 45% body weight (BW) for verbal instruction and weight scale method, respectively, to 33% BW for the WBI device. In addition, PWB compliance using the WBI device was not dependent on subject weight like the standard of care approaches. Sometimes patients are instructed not only to avoid exceeding an upper load limit, but also to maintain their limb load above a lower limit as well. A newer version of the WBI has been developed that provides two distinct clicks to a patient corresponding to an upper and lower load limits.

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Development of a Wearable Live-feedback System to Support Partial Weight-bearing While Recovering From Lower Extremity Injuries

Procedia Engineering ◽

10.1016/j.proeng.2016.06.206 ◽

2016 ◽

Vol 147 ◽

pp. 157-162 ◽

Cited By ~ 3

Author(s):

A. Tkachenko Bril ◽

V. David ◽

M. Scherer ◽

H. Jagos ◽

P. Kafka ◽

...

Keyword(s):

Lower Extremity ◽

Weight Bearing ◽

Feedback System ◽

Partial Weight Bearing ◽

Lower Extremity Injuries ◽

Extremity Injuries ◽

Partial Weight

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ORTHOPEDIC INJURIES IN ADOLESCENT GYMNASTS: A SYSTEMATIC REVIEW

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121s00117 ◽

2021 ◽

Vol 9 (7_suppl3) ◽

pp. 2325967121S0011

Author(s):

Katie Kim ◽

Michael Saper

Keyword(s):

Lower Extremity ◽

Upper Extremity ◽

Weight Bearing ◽

The Body ◽

Adolescent And Young Adult ◽

Body Region ◽

Lower Extremity Injuries ◽

Common Location ◽

Orthopedic Injuries ◽

Extremity Injuries

Background: Gymnastics exposes the body to many different types of stressors ranging from repetitive motion, high impact loading, extreme weight bearing, and hyperextension. These stressors predispose the spine and upper and lower extremities to injury. In fact, among female sports, gymnastics has the highest rate of injury each year. Purpose: The purpose of this study was to systematically review the literature on location and types of orthopedic injuries in adolescent (≤20 years) gymnasts. Methods: The Pubmed, Medline, EMBASE, EBSCO (CINAHL) and Web of Science databases were systematically searched according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to identify all studies reporting orthopedic injuries in adolescent and young adult gymnasts. All aspects of injuries were extracted and analyzed including location, type and rates of orthopedic injuries. Results: Screening yielded 22 eligible studies with a total of 427,225 patients. Twenty of 22 studies reported upper extremity injuries of which four specifically focused on wrist injuries. Eight studies reported lower extremity injuries. Nine studies reported back/spinal injuries. Seven studies investigated each body location of injury; one study reported the upper extremity as the most common location for injury and six studies reported the lower extremity as the most common location for injury. Of those seven studies, five (23%) reported sprains and strains as the most common injury. One study reported fractures as the most common injury. Conclusion: There is considerable variation in reported injury location. Some studies focused specifically on the spine/back or wrist. The type of gymnastics each patient participated in was also different, contributing to which area of the body was more heavily stressed, or lacking. Current literature lacks data to fully provide evidence regarding which body region is more frequently injured and the type of injury sustained.

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An Inexpensive Weight Bearing Indicator Used for Rehabilitation of Patients With Lower Extremity Injuries

Journal of Medical Devices ◽

10.1115/1.2355690 ◽

2006 ◽

Vol 1 (1) ◽

pp. 38-46 ◽

Cited By ~ 2

Author(s):

Daniel F. Walczyk ◽

John P. Bartlet

Keyword(s):

Lower Extremity ◽

Medical Device ◽

Weight Bearing ◽

Performance Testing ◽

Buckling Load ◽

Manufacturing Cost ◽

Lower Extremity Injuries ◽

New Device ◽

Load Monitoring ◽

Extremity Injuries

Background. Partial or nonweight bearing is a useful treatment prescribed by medical professionals (e.g., orthopedists, podiatrists) for patients rehabilitating from lower extremity injuries However, there is significant variability in patient conformance with the commonly used, but very imprecise “weight scale method.” Furthermore, the few commercially available load monitoring devices are rarely used because of their high cost. Method of Approach. As a simple and inexpensive alternative to current load monitoring methods and commercial products, a new medical device called a snap dome weight bearing indicator (WBI) has been developed to gently warn a patient when they have exceeded a limited percentage of their body weight on the recovering leg or foot. When installed in a patient’s shoe or medical appliance, the device does so by utilizing the reversible buckling phenomena of a snap dome to provide a tactile and audible feedback when the prescribed weight has been exceeded. To demonstrate the feasibility of this new device, the performance of (1) the snap dome by itself and (2) several WBI designs developed were tested. The most useful of the new designs include one incorporating a heel cup for loose fitting medical appliances and a podiatric off-loading indicator (POLI). In addition, a pilot study and manufacturing cost analysis of the POLI device were performed to investigate patient usability and affordability issues. Results. The particular four-leg snap domes used in device prototypes performed quite well with regards to buckling load consistency between domes, the linearity of buckling load by stacking domes in a parallel arrangement, and buckling load repeatability of a single dome. The performance of each WBI prototype was tested with regards to load transfer, tactile, and audible feedback to the patient, patient comfort, and ease of installation. Prototype performance was generally very good or excellent except for the POLI device, which does not provide sufficient tactile or audible feedback for many patients. A costing analysis of the POLI device suggests that it can be manufactured in the U.S. for around one dollar. Conclusions. The generally positive results from performance testing of commercially available snap domes and WBI prototypes suggest that this new medical device will indeed be an inexpensive, yet effective conformance tool for orthopedists and podiatrists to use in prescribing partial or no weight bearing for a patient.

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Orthopedic Surgeons and Physical Therapists Differ in Assessment of Need for Physical Therapy After Traumatic Lower-Extremity Injury

Physical Therapy ◽

10.2522/ptj.20080200 ◽

2009 ◽

Vol 89 (12) ◽

pp. 1337-1349 ◽

Cited By ~ 12

Author(s):

Kristin R. Archer ◽

Ellen J. MacKenzie ◽

Renan C. Castillo ◽

Michael J. Bosse ◽

Keyword(s):

Physical Therapy ◽

Lower Extremity ◽

Self Efficacy ◽

Knee Flexion ◽

Physical Therapist ◽

Weight Bearing ◽

Lower Extremity Injury ◽

Trauma Centers ◽

Lower Extremity Injuries ◽

Extremity Injuries

Background Lower-extremity injuries constitute the leading cause of trauma hospitalizations among people under the age of 65 years. Rehabilitation has the potential to favorably influence the outcomes associated with traumatic lower-extremity injuries. Objectives The objectives of this study were to explore variability in surgeon and physical therapist assessments of the need for physical therapy in patients with traumatic lower-extremity injuries and to determine the factors associated with assessments of need. Design This study was a retrospective cohort investigation. Methods Participants were 395 patients treated by reconstruction in the Lower-Extremity Assessment Project. They were evaluated at 8 level I trauma centers at 3, 6, and 12 months after hospitalization by an orthopedic surgeon and a physical therapist to determine the need for physical therapy. Analyses included multilevel logistic regression. Results Chi-square analyses showed that surgeon and therapist assessments of need differed statistically across trauma centers. Surgeons were more likely to assess a need for therapy at 3 months when participants had low work self-efficacy, impaired knee flexion range of motion (ROM), and weight-bearing limitations and at 6 and 12 months when participants had impaired knee flexion ROM and weight-bearing and balance limitations. Therapists were more likely to assess a need for therapy at 3 months when participants had moderate to severe pain and at 6 and 12 months when participants had low work self-efficacy, pain, impaired knee flexion ROM, and balance limitations. Conclusions The results revealed variability in assessments of the need for physical therapy at the provider and trauma center levels. Differences in provider assessments highlight the need for communication and further investigation into the outcomes and timing of physical therapy for the treatment of traumatic lower-extremity injuries.

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Judgment and Approach for Management of Severe Lower Extremity Injuries

Clinics in Plastic Surgery ◽

10.1016/s0094-1298(20)30851-8 ◽

1991 ◽

Vol 18 (3) ◽

pp. 525-543 ◽

Cited By ~ 2

Author(s):

Robert L. Walton ◽

Douglas M. Rothkopf

Keyword(s):

Lower Extremity ◽

Lower Extremity Injuries ◽

Extremity Injuries

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Concussion in National Football League Athletes Is Not Associated With Increased Risk of Acute, Noncontact Lower Extremity Musculoskeletal Injury

Orthopaedic Journal of Sports Medicine ◽

10.1177/23259671211003491 ◽

2021 ◽

Vol 9 (5) ◽

pp. 232596712110034

Author(s):

Toufic R. Jildeh ◽

Fabien Meta ◽

Jacob Young ◽

Brendan Page ◽

Kelechi R. Okoroha

Keyword(s):

Lower Extremity ◽

National Football League ◽

Field Performance ◽

Return To Play ◽

Lower Extremity Injury ◽

Extremity Injury ◽

Lower Extremity Injuries ◽

Increased Risk ◽

Extremity Injuries ◽

And Control

Background: Impaired neuromuscular function after concussion has recently been linked to increased risk of lower extremity injuries in athletes. Purpose: To determine if National Football League (NFL) athletes have an increased risk of sustaining an acute, noncontact lower extremity injury in the 90-day period after return to play (RTP) and whether on-field performance differs pre- and postconcussion. Study Design: Cohort study, Level of evidence, 3. Methods: NFL concussions in offensive players from the 2012-2013 to the 2016-2017 seasons were studied. Age, position, injury location/type, RTP, and athlete factors were noted. A 90-day RTP postconcussive period was analyzed for lower extremity injuries. Concussion and injury data were obtained from publicly available sources. Nonconcussed, offensive skill position NFL athletes from the same period were used as a control cohort, with the 2014 season as the reference season. Power rating performance metrics were calculated for ±1, ±2, and ±3 seasons pre- and postconcussion. Conditional logistic regression was used to determine associations between concussion and lower extremity injury as well as the relationship of concussions to on-field performance. Results: In total, 116 concussions were recorded in 108 NFL athletes during the study period. There was no statistically significant difference in the incidence of an acute, noncontact lower extremity injury between concussed and control athletes (8.5% vs 12.8%; P = .143), which correlates with an odds ratio of 0.573 (95% CI, 0.270-1.217). Days (66.4 ± 81.9 days vs 45.1 ± 69.2 days; P = .423) and games missed (3.67 ± 3.0 vs 2.9 ± 2.7 games; P = .470) were similar in concussed athletes and control athletes after a lower extremity injury. No significant changes in power ratings were noted in concussed athletes in the acute period (±1 season to injury) when comparing pre- and postconcussion. Conclusion: Concussed, NFL offensive athletes did not demonstrate increased odds of acute, noncontact, lower extremity injury in a 90-day RTP period when compared with nonconcussed controls. Immediate on-field performance of skill position players did not appear to be affected by concussion.

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EFFECTIVENESS OF PRE-SEASON PHYSICAL PERFORMANCE TESTS IN IDENTIFYING IN-SEASON LOWER EXTREMITY INJURIES IN ADOLESCENT GYMNASTS

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967121s00141 ◽

2021 ◽

Vol 9 (7_suppl3) ◽

pp. 2325967121S0014

Author(s):

Danielle A Farzanegan ◽

Emily Francione ◽

Nicole Melfi

Keyword(s):

Lower Extremity ◽

Physical Performance ◽

Performance Tests ◽

Kinetic Chain ◽

Chi Square ◽

Balance Test ◽

Lower Extremity Injuries ◽

Common Location ◽

Acute Injuries ◽

Extremity Injuries

Background: Artistic competitive gymnastics results in a wide, unique spectrum of injuries. Due to the high number of injuries and the current lack of research related to pre-competitive testing in adolescent gymnasts, it is crucial to find a method to predict the likelihood of an athlete sustaining an in-season injury. Purpose: The purpose of this study was to 1) describe the frequency and type of pre-season and in-season injuries, 2) determine if there were differences in physical performance tests between those who had a lower extremity (LE) injury in-season and those who did not, and 3) determine if there were differences in age, level, sex, BMI, sport modifications, previous injury, and current injury between those who had a LE injury and those who didn’t. Methods: Thirty-seven adolescent gymnasts (average age: 12.81 years) were included with levels ranging from 5 (novice) to 10 (elite). Participants (15 males and 22 females) were surveyed for previous and current injury. The athletes completed a performance battery before the competition season including: Lower Quarter Y-Balance Test (LQYBT), Closed Kinetic Chain dorsiflexion (CKCDF), single hop (SH), triple hop (TH), and the Functional Movement Screen (FMS). Follow-up data was collected at the end of the competitive season for comparison. The data was analyzed using descriptive methods and comparative analyses including chi-square and independent t-tests with an alpha level set at .05. Results: Sixty-five percent reported an injury in the last year and seventy-eight percent reported pre-season injuries at testing day. The most common location for pre-season injury was the ankle/foot (24% and 31% respectively). There were no differences between injured and non-injured athletes when comparing asymmetries in CKCDF, LQYBT posteromedial or posterolateral reach, hop testing, or FMS. The LQYBT-anterior scores were significantly different at p=.049 between the injured versus uninjured groups, with 91% of the in-season injury group having a difference <4cm. Similarly, the LQYBT-composite score using a cut-off of 95% was significant at p=.043 with those >95% category being more likely to get injured. There were no significant differences in demographic information comparing injury occurrence. Conclusion: The tested physical performance battery may be useful in tracking gymnasts over time, but may not be beneficial in forecasting injuries in a sport with high percentages of acute injuries. The collected injury volume may not be reflective of a standard season as COVID-19 decreased the number of competitions. Additional research to identify athletes at risk for injury requires further investigation.

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