The range of movement of the thumb

The Female Thumb Carpometacarpal Joint: Motion and Force Changes Due to Arthritis and Surgical Intervention

Thumb carpometacarpal (CMC) osteoarthritis (OA) has been one of the most common locations of hand OA. CMC OA disproportionately occurs in females over males. In severe cases, surgical intervention may be needed. However, to determine the effects of surgical treatment, normative, pre-, and postsurgery function must be understood. The goals of this work were to compare the thumb motion and force abilities of older healthy (OH) females without CMC OA to those of females with CMC OA and who received ligament reconstruction with tendon interposition (LRTI) surgery at time points presurgery, 3- and 6-months postsurgery. On average, CMC OA participants 3- and 6-months postsurgery showed 35.6% and 32.9% less overall metacarpal motion compared to presurgery, 31.9% and 29.1% less than OH, and exhibited altered motion. Metacarpal flexion/extension and abduction/adduction ranges were 51.9 deg and 43.4 deg for OH, 52.9 deg and 40.3 deg presurgery, 39.9 deg and 33.5 deg at 3-months, and 42.6 deg and 32.7 deg at 6-months postsurgery. On average, participants had increased force generation at 6-months postsurgery compared to presurgery, and 20% of participants returned to the level of OH females. These data sets highlight changes in thumb metacarpal movement and thumb force generation due to disease and surgical intervention. This work has the ability to support both surgeons and patients through improved outcome assessments as well as additional data to inform the decision process on intervention.

Clinical outcomes after primary repair for thumb ulnar collateral ligament ruptures: a systematic review and meta-analysis

There is no consensus on the best surgical technique for treating thumb ulnar collateral ligament (UCL) ruptures. This systematic review and meta-analysis investigates which primary repair technique and postoperative immobilization protocol result in the best clinical outcomes. A literature search was conducted in Embase, Medline ALL Ovid, Web of Science Core Selection and Cochrane Central Register of Controlled Trials. Pain, stability, tip pinch strength, key pinch strength, grip strength, return to work and metacarpophalangeal joint range of motion were collected as postoperative outcomes. In total, 29 studies were included. All surgical techniques resulted in satisfactory clinical outcomes, with no significant differences between bone anchor reinsertion, suture fixation, K-wire fixation and a combination of techniques. K-wire immobilization resulted in worse postoperative pain, but similar stability compared to immobilization without a K-wire. Clinical outcomes after thumb UCL repair are excellent, with no differences in clinical outcomes noted among surgical techniques.

Thumb Pronation Angle in Thumb Opposition Evaluated by the Nail Tip Angle of Thumb-Ring Finger Opposition

BACKGROUND

This study aimed to devise the method for the evaluation of the thumb pronation angle and calculate its reference value.

METHODS

The study was conducted from October 2021 to March 2022, and 600 hands of 300 healthy volunteers were included in this study. The participants were divided into 6 age groups with 50 participants each. In study 1, 12 participants from group 1 were randomly selected, which included 6 male and 6 female participants. We measured the thumb pronation angle using FASTRAK system and the nail tip angle of thumb-ring finger opposition (T-R angle) and also evaluated the relation between them. In study 2, we measured the T-R angle of 600 hands of 300 healthy volunteers. The T-R angle mean (SD) and 95% confidence interval (CI) of each age group were calculated as reference values.

RESULTS

The thumb pronation angle was correlated with the T-R angle. The T-R angle mean (SD) and 95% CI of the 6 groups were as follows: group 1, 142.5° (12.4) and 117.7 to 167.3; group 2, 139.9° (10.1) and 119.7 to 160.1; group 3, 142.3° (9.7) and 122.9 to 160.5; group 4, 140.2° (12.6) and 115.0 to 165.4; group 5, 138.3° (11.9) and 114.5 to 162.1; and group 6, 135.4° (13.0) and 109.4 to 161.4. The 95% CI tended to decrease with an increasing age.

CONCLUSIONS

The T-R angle was a suitable evaluation method for the thumb pronation angle, and it should be evaluated by age groups.

A Novel Soft Glove Utilizing Honeycomb Pneumatic Actuators (HPAs) for Assisting Activities of Daily Living

Fabric-based pneumatic actuators (FPAs) are extensively employed in the design of lightweight and compliant soft wearable assistive gloves. However, conventional FPAs typically exhibit limited output force, thereby restricting the applications of such gloves. This paper presents the development of a novel honeycomb pneumatic actuator (HPA) constructed using flexible thermoplastic polyurethane (TPU) coating through hot pressing or ultrasonic welding techniques. Compared to the previously utilized double-layer fabric-based pneumatic actuators (DLFPAs), the HPAs yields a remarkable 862% increase in end output force. It can produce a tip force of 13.57 N at a pressure of 150 kPa. The integration of HPAs onto a soft pneumatic glove enables the facilitation of various activities of daily living. A series of trials involving nine patients were conducted to assess the effectiveness of the soft glove. The experimental results indicate that when assisted by the glove, the patients' finger metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints achieved angles of 87.67 ± 19.27° and 64.2 ± 30.66°, respectively. Additionally, the average fingertip force reached 10.16 ± 4.24 N, the average grip force reached 26.04 ± 15.08 N, and the completion rate of daily functions for the patients increased from 39% to 76%. These outcomes demonstrate that the soft glove effectively aids in finger movements and significantly enhances the patients' daily functioning.

Outcomes Associated with Moberg and Modified Moberg Flaps in Thumb Reconstruction: A Systematic Review

Background: Appropriate thumb function is critical as it is makes up approximately 40% of the hand's function leading to the greatest influence in activities of daily living (ADLs). Local flaps are the primary option for thumb reconstruction, of which the Moberg flap has been reported to have the added advantage of its advancement capacity relative to other flaps. This systematic review aims to describe the outcomes of the Moberg advancement flap and its associated modifications for coverage of palmar thumb defects. Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed for the conduct of this systematic review. Medline, Embase, CINAHL and Cochrane Library were systematically searched to retrieve relevant citations. Title and abstract as well as full-text assessment were performed in duplicate. Full texts were extracted by one reviewer and data extracted was confirmed by a second. Complication rates and overall means were calculated for the appropriate outcomes. Results: A total of 1,794 citations were retrieved; 15 papers were retained, including 169 patients. The overall mean follow-up was 28.6 months (n = 5 studies). In 136 patients, there was 100% flap viability (n = 12 studies). With regard to thumb aesthetics, 92% (59/64 patients) had favourable outcomes (n = 6 studies). No evidence of postoperative flexion contractures (n = 0/56 patients, 5 studies) was found. Cold intolerance occurred at a rate of 29.8% (n = 17/57, 4 studies) and the infection rate was 10.3% (6/58 patients, 3 studies). Conclusions: Moberg/modified Moberg flaps are a safe option for thumb reconstruction given their associated postoperative outcome and complication profile. Level of Evidence: Level III (Therapeutic).

WITHDRAWN: Long-term follow-up results of a dorsal approach to complex dorsal metacarpophalangeal dislocation

PURPOSE

The present study aimed to examine the dorsal approach to complex MCP joint dislocation and to compare our clinical results with others reported in the literature.

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Support for mechanical advantage hypothesis of grasping cannot be explained only by task mechanics

Successful object interaction during daily living involves maintaining the grasped object in static equilibrium by properly arranging the fingertip contact forces. According to the mechanical advantage hypothesis of grasping, during torque production tasks, fingers with longer moment arms would produce greater normal force than those with shorter moment arms. Previous studies have probed this hypothesis by investigating the force contributions of individual fingers through systematic variations (or perturbations) of the properties of the grasped handle. In the current study, we examined the validity of this hypothesis in a paradigm wherein the thumb tangential force was constrained to a minimal constant magnitude. This was achieved by placing the thumb on a freely movable slider platform. The total mass of the handle was systematically varied by adding external loads directly below the center of mass of the handle. Our findings suggest that the mechanical advantage hypothesis manifests only during the heaviest loading condition when a threshold difficulty is reached. We infer that the support for the mechanical advantage hypothesis depends not only on the physical parameters but also on the individual ability to manage the task.

Effect of the position of the interphalangeal joint on movements of the trapeziometacarpal joint during thumb opposition

The Kapandji test is a simple method to score thumb opposition; however, the position of the interphalangeal joint of the thumb during this test has not been described. We aimed to quantitatively examine the effect of the thumb interphalangeal joint position on movements of the trapeziometacarpal joint during thumb opposition using the Kapandji test. The Kapandji test was carried out in 20 healthy participants during thumb interphalangeal joint extension and flexion. Movements of the joints and the activity of thenar muscles were recorded using motion capture and electromyography, respectively. We found that interphalangeal joint extension increased the trapeziometacarpal joint movement and thenar muscle activity compared with interphalangeal joint flexion, which contributed to thumb opposition at Kapandji Positions 0-6. These findings suggest the position of the thumb interphalangeal joint affects the trapeziometacarpal joint during thumb opposition, and assessment of thumb opposition using the Kapandji test is best done with the thumb interphalangeal joint in extension.

Towards an Extensive Thumb Assist: A Comparison between Whole-Finger and Modular Types of Soft Pneumatic Actuators

Soft pneumatic actuators used in robotic rehabilitation gloves are classified into two types: whole-finger actuators with air chambers that cover the entire finger and modular actuators with chambers only above the finger joints. Most existing prototypes provide enough finger flexion support, but insufficient independent thumb abduction or opposition support. Even the latest modular soft actuator realized thumb abduction with a sacrifice of range of motion (RoM). Moreover, the advantages and disadvantages of using the two types of soft actuators for thumb assistance have not been made clear. Without an efficient thumb assist, patients’ options for hand function rehabilitation are very limited. Therefore, the objective of this study was to design a modular actuator (M-ACT) that could support multiple degrees of freedom, compare it with a whole-finger type of thumb actuator with three inner chambers (3C-ACT) in terms of the RoM, force output of thumb flexion, and abduction, and use an enhanced Kapandji test to measure both the kinematic aspect of the thumb (Kapandji score) and thumb-tip pinch force. Our results indicated superior single-DoF support capability of the M-ACT and superior multi-DoF support capability of the 3C-ACT. The use of the 3C-ACT as the thumb actuator and the M-ACT as the four-finger actuator may be the optimal solution for the soft robotic glove. This study will aid in the progression of soft robotic gloves for hand rehabilitation towards real rehabilitation practice.

Assessment of the Effect of Smartphone Usage on the Range of Motion and Fatigability of the Joints and Muscles of the Thumb Among Users: A Cross-Sectional Study in Central India

Introduction

The ability of adaptation is unique to humankind. Technology advances have introduced many appliances that increasingly are smaller in size and handheld. These devices on prolonged usage affect the thumb joint complex, and this study was therefore designed to assess any changes in the movement of the thumb joint complex and fatigability secondary to the increasing usage of smartphones in different orientations in the Central Indian population.

Materials and methods

An analytical cross-sectional study was performed to assess changes in the ranges of motion (ROM) of the thumb joint complex with a sample size of 137 selected nonrandomly and categorized on the basis of the orientation of smartphone usage by physical goniometer and a standardized questionnaire to assess fatigability.

Results

Most movements of the thumb joint complex corresponded to the existing standard values. The study found significant changes in the movement of passive flexion of the left metacarpophalangeal (MCP) joint and borderline significant modifications in the active extension of the left interphalangeal (IP) joint, passive extension of the left interphalangeal joint, and passive flexion of the left carpometacarpal (CMC) joint among the groups of participants. The Borg CR10 value of fatigue was “one,” indicative of no excessive fatigue after smartphone usage.

Conclusion

There are no significant changes in the ranges of motion of the joint complex of the thumb in mobile phone users over a period of time. The orientations and the increased duration of usage also did not cause any fatigue in the muscles of the thumb.

Functional Recovery Following Trapeziectomy and Ligament Reconstruction and Tendon Interposition: A Prospective Longitudinal Study

PURPOSE

Patients undergoing surgery for trapeziometacarpal (TMC) joint arthritis require preoperative counseling on the expectations of surgery. This study aims to document the objective and functional recovery over the initial 12 months following trapeziectomy and ligament reconstruction with tendon interposition (LRTI).

METHODS

We prospectively followed 55 patients with symptomatic TMC joint osteoarthritis after trapeziectomy and LRTI. Patients were assessed on functional outcome measures, pain, and objective outcomes of grip, tip and key pinch strength, and range of motion. Outcomes were recorded preoperatively and at 3, 6, 9, and 12 months after surgery.

RESULTS

Outcome measures of Disabilities of the Arm, Shoulder, and Hand (DASH), Patient-Rated Wrist Evaluation (PRWE), and pain, improved significantly after surgery at each 3-month interval up to 9 months. Palmar and radial abduction were significantly improved compared to their preoperative ranges, but opposition was unchanged. Power grip significantly exceeded the preoperative strength at 6 months and further increased at 9 months. Tip pinch significantly exceeded the preoperative strength at 12 months. There was no difference in the key pinch strength compared to the preoperative strength.

CONCLUSIONS

Over a follow-up period of 12 months, trapeziectomy and LRTI is an effective treatment in significantly reducing pain in 80% of patients. Although normal patient-reported outcome measures of DASH and PRWE are not regained, when compared to normative values, these measures are significantly improved; the improvement plateaus at 9 months. Patients can expect to attain 37% and 46% of their eventual measured DASH and PRWE scores, respectively, at 3 months, and 82% and 79% of their eventual measured DASH and PRWE scores, respectively, at 6 months. Grip strength exceeded the preoperative strength by 15% at 6 months and by 30% at 9 months. Tip pinch strength significantly exceeded the preoperative strength by 20% at 9 months.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

Double trapeziometacarpal and scaphotrapeziotrapezoidal pyrocarbon interposition implants for pantrapezial arthritis: Midterm results and surgical technique

BACKGROUND

Pantrapezial osteoarthritis of the thumb (OA) includes involvements of scaphotrapezoidtrapezoidal (STT) and trapeziometacarpal (TM) joints which are source of disabling pain and function loss. Whilst radical procedures or arthroplasties are available, more conservative techniques have been developed recently and have gain popularity. They aim of this study was to know the midterms results of patients presenting peritrapezial OA treated with a double interposition pyrocarbon implant at the STT and TM joints. Our hypothesis was that patients suffering from pantrapezial OA treated with this technique would improve their functional scores at the last follow-up.

PATIENTS AND METHODS

This descriptive, retrospective, observational study analysed 31 patients treated with a double STT and TM pyrocarbon interposition implant ("Burger arthroplasty") between 2009-2018. Patients were clinically and radiologically diagnosed with pantrapezial OA before surgery (Eaton stage I or II). The primary endpoint was the comparison of the preoperative and postoperative values of the functional scores QuickDASH and PRWE. Epidemiological data and radiological results were reported. Pain, range of motion, pinch and grip strength, were analysed with standardised tools. The surgical technique was described in detail and reinforced with a didactic supplementary video.

RESULTS

Eighteen patients were available for analysis (58%) with a mean age of 62 years (range: 49-79). At last follow-up (44 months, range: 9-95) we found significant reduced pain, significant improvement of QuickDASH and PRWE scores and of pinch strength (p<0.05). Range of motion, grip and pinch strength did not improve significantly (p>0.05). Two patients required revision surgery.

DISCUSSION

The double STT and TM pyrocarbon interposition offer good results at midterm on patient suffering from early stages of pantrapezial OA with preserved trapezium structure.

LEVEL OF EVIDENCE

IV.

Phalangeal and Metacarpal Fractures in Children: A 10-Year Comparison of Factors Affecting Functional Outcomes in 313 Patients

Introduction  It is widely believed that fractures in children have excellent clinical outcomes due to their capacity to remodel. There are, however, certain fractures that require careful management to avoid long-lasting functional impairment. Functional outcomes following hand fractures in children are poorly studied.

Materials and Methods  We performed a retrospective cohort study of consecutive children and adolescents who had operative treatment for metacarpal and phalangeal fractures (2008–2018). Tuft fractures and replantations were excluded. Functional outcomes were measured by total active motion (TAM) scoring, where a “good” outcome = TAM > 75%. Fractures were categorized by location, classification, and by the fixation they required.

Results  Three hundred thirteen children were included. For proximal phalangeal fractures, those treated by manipulation under anesthesia, had a higher proportion of “good” functional outcomes than Kirschner-wire or open reduction internal fixation at discharge from hand therapy ( p  = 0.043). Middle phalanx fractures had excellent functional outcomes, with no difference between fixation methods ( p  = 0.81). For metacarpals, there was no statistically significant difference in functional outcomes across all managements ( p  = 0.134). Fractures in the thumb had poorer postoperative function at mean 7.26 weeks than those in the long fingers ( p  < 0.0001), and the data suggested a trend toward worse outcomes in the distal phalanx, pediatric Bennett fractures, Seymour fractures, and oblique fractures.

Conclusions  Fractures in the thumb and phalangeal fractures that require percutaneous or open fixation may need closer early postoperative monitoring in children to optimize their potential for good function.

Is Thumb Proprioception Decreased in Patients With Trapeziometacarpal Joint Osteoarthritis?

Proprioception is thought to be essential for normal joint homeostasis, and its decreased function has been associated with an increased risk of joint diseases. However, only a few studies have been performed on the association between proprioceptive function in the trapeziometacarpal joint (TMCJ) and osteoarthritis. The purpose of this study was to compare TMCJ proprioceptive function in elderly women with radiographic TMCJ osteoarthritis relative to age-matched control women without osteoarthritis. We enrolled 19 women (mean age, 66 years) with symptomatic, radiographic Eaton and Littler grade 2, 3, and 4 TMCJ osteoarthritis and 19 age-matched control women without osteoarthritis. We evaluated thumb proprioception by using a joint-position reproduction test and compared the reposition error (RE) between the groups. We carried out a multivariate analysis for factors potentially associated with increased RE, such as age, body mass index, hand dominance, the presence of diabetes, pain level, and the presence of osteoarthritis. Also, a logistic regression analysis was performed for factors associated with the occurrence of TMCJ osteoarthritis. Patients with TMCJ osteoarthritis had greater RE than did the control patients in the joint-position reproduction test at 20°, 30°, and 40° of thumb palmar abduction. The multivariate analysis indicated that increased RE was associated with the presence of osteoarthritis, but not with the other factors assessed. The occurrence of TMCJ osteoarthritis was associated with increased RE at 20°, 30°, and 40° of thumb palmar abduction. This study showed that decreased proprioceptive function was associated with the presence of osteoarthritis in the TMCJ, although the causality remains unknown. Further studies on the role of proprioception in the pathogenesis of TMCJ osteoarthritis and the potential role of its training for disease prevention or treatment are required.

Ergonomics in Endourology: Measurement of Force for Deflection in Contemporary Ureteroscopes

Introduction: Few studies have examined the ergonomic hazards to endourologists during endoscopic procedures. We have evaluated the forces required to deflect different flexible ureteroscopes across a range of measurements with several different standard instruments within the working channel. Methods: Five ureteroscopes were studied: the Uscope, Neoflex, LithoVue^™, URF-P6, and the Flex-X2^™. A pull-force meter (Nextech DFS 500) was attached to the thumb lever to deflect the tip from 30° to 210° at 30° intervals. Measurements were made with upward and downward deflection separately. The forces were reported in Newtons (N) to the nearest 10th, as positive values regardless of the direction of the force. Measurements were made with the channel empty or containing an instrument: a 365 μm laser fiber, a 2.4F Nitinol basket, 3F biopsy forceps, or a 0.038" guidewire using the flexible or the stiff tip. Results: The maximum downward deflection force, measured at 210° of deflection, with an empty channel range from a minimum of 5.7 N in one scope to a maximum of 33.4 N in another. The force necessary for deflection ranges from 2.0 to 7.0 N (0.45-1.57 foot-pounds) at 30° to 8.5 to 25.3 N (1.8-5.69) at 180°. Maximum upward deflection shows similar results with a minimum of 7.9 N in one scope and a maximum of 43.1 N of force in another. Working instruments in the channel increased the force needed for deflection. Conclusions: Forces required for steep deflection of the tip of a flexible ureteroscope reach extremely high levels or limit the deflection capability of the scope. The force is higher with increased deflection and with instruments within the channel.

Evaluation and Management of Carpal Fractures Other Than the Scaphoid

Fractures of the carpus can be debilitating injuries and often lead to chronic pain and dysfunction when not properly treated. Although scaphoid fractures are more common, fractures of the other carpal bones account for nearly half of all injuries of the carpus. Often missed on initial presentation, a focused physical examination with imaging tailored to the suspected injury is needed to identify these fractures. In addition to plain radiographs, advanced imaging such as CT and MRI are helpful in diagnosis and management. Treatment of carpal fractures is based on the degree of displacement, stability of the fracture, and associated injuries. Those that require surgical fixation often affect the congruency of the articular surfaces, are unstable, are at risk for symptomatic nonunion, are associated with notable ligamentous injury, or are causing nerve or tendon entrapment. Surgical strategies involve percutaneous Kirschner wires, external fixation, screws and/or plates, excision, or fusion for salvage. Owing to the intimate articulations in the hand, small size of the carpal bones, and complex vascular supply, carpal fracture complications include symptomatic nonunion, osteonecrosis, and posttraumatic arthritis.

Device Development for Detecting Thumb Opposition Impairment Using Carbon Nanotube-Based Strain Sensors

Research into hand-sensing is the focus of various fields, such as medical engineering and ergonomics. The thumb is essential in these studies, as there is great value in assessing its opposition function. However, evaluation methods in the medical field, such as physical examination and computed tomography, and existing sensing methods in the ergonomics field have various shortcomings. Therefore, we conducted a comparative study using a carbon nanotube-based strain sensor to assess whether opposition movement and opposition impairment can be detected in 20 hands of volunteers and 14 hands of patients with carpal tunnel syndrome while avoiding existing shortcomings. We assembled a measurement device with two sensors and attached it to the dorsal skin of the first carpometacarpal joint. We measured sensor expansion and calculated the correlation coefficient during thumb motion. The average correlation coefficient significantly increased in the patient group, and intrarater and interrater reliability were good. Thus, the device accurately detected thumb opposition impairment due to carpal tunnel syndrome, with superior sensitivity and specificity relative to conventional manual inspection, and may also detect opposition impairment due to various diseases. Additionally, in the future, it could be used as an easy, affordable, and accurate sensor in sensor gloves.

Complex thumb motions and their potential clinical value in identifying early changes in function

BACKGROUND

Early diagnosis and treatment of osteoarthritis of the thumb allows for early interventions that may mitigate osteoarthritis progression and decrease severity later in life. Early identification of motion changes is limited by the clinical reliance on single planar measurements using goniometry. Multi-planar measurements using motion capture can provide insights into joint function and pathophysiology that cannot be obtained from single-plane goniometry measurements. Thus, the goals of this research were 1) to determine differences in thumb motions across three groups of participants (young healthy (n = 23), older healthy (n = 11), and those with carpometacarpal osteoarthritis (n = 24)) and 2) to determine if multi-planar motions provided additional movement information in comparison to standard planar measures.

METHODS

In this study, a motion capture system was used to collect standard clinical ranges of motion and complex multi-planar tasks. Differences in motion patterns due to aging and osteoarthritis were identified. Motions tested included palmar adduction-abduction, radial adduction-abduction, metacarpophalangeal flexion-extension, interphalangeal flexion-extension, functional adduction-abduction, opposition, and circumduction.

FINDINGS

Results indicated that motion capture was capable of detecting changes in carpometacarpal mobility that were not detected using standard approaches. Our results suggested that use of multi-planar measurements have the potential to identify changes that are indicators of early stages of osteoarthritis.

INTERPRETATION

Early indicators are clinically useful as they will enhance patient treatment by permitting the application of treatment approaches sooner, potentially leading to reduced overall functional deficits.

Long-term outcomes after pollicization: a mean 11-year follow-up study

This study evaluates the long-term results of pollicization for a congenitally absent or severely hypoplastic thumb. Twenty-nine patients with 34 pollicizations were divided to two groups: those with simple thumb hypoplasia (22 pollicizations) and those with radial longitudinal dysplasia (12 pollicizations). The patients were followed from 1.3 to 32 years, with a mean follow-up time of 11 years. The patients were examined clinically and radiologically, and they completed a questionnaire concerning satisfaction with appearance, function, and social interaction. The Percival score was also calculated. In both groups, grip and pinch strengths of the operated hands were inferior to the normative age-related values. Radiologically, flattening of the original metacarpal head was found in 20 out of the 34 operated hands. We found better patient satisfaction in the simple hypoplasia group than in the radial longitudinal dysplasia group. The functional outcomes and patients' satisfaction did not correlate with the age of patients at operation. Level of evidence: IV.

Trabecular variation in the first metacarpal and manipulation in hominids

OBJECTIVES

The dexterity of fossil hominins is often inferred by assessing the comparative manual anatomy and behaviors of extant hominids, with a focus on the thumb. The aim of this study is to test whether trabecular structure is consistent with what is currently known about habitually loaded thumb postures across extant hominids.

MATERIALS AND METHODS

We analyze first metacarpal (Mc1) subarticular trabecular architecture in humans (Homo sapiens, n = 10), bonobos (Pan paniscus, n = 10), chimpanzees (Pan troglodytes, n = 11), as well as for the first time, gorillas (Gorilla gorilla gorilla, n = 10) and orangutans (Pongo sp., n = 1, Pongo abelii, n = 3 and Pongo pygmaeus, n = 5). Using a combination of subarticular and whole-epiphysis approaches, we test for significant differences in relative trabecular bone volume (RBV/TV) and degree of anisotropy (DA) between species.

RESULTS

Humans have significantly greater RBV/TV on the radiopalmar aspects of both the proximal and distal Mc1 subarticular surfaces and greater DA throughout the Mc1 head than other hominids. Nonhuman great apes have greatest RBV/TV on the ulnar aspect of the Mc1 head and the palmar aspect of the Mc1 base. Gorillas possessed significantly lower DA in the Mc1 head than any other taxon in our sample.

DISCUSSION

These results are consistent with abduction of the thumb during forceful "pad-to-pad" precision grips in humans and, in nonhuman great apes, a habitually adducted thumb that is typically used in precision and power grips. This comparative context will help infer habitual manipulative and locomotor grips in fossil hominins.

Measurement of thumb pronation and palmar abduction angles with a small motion sensor: a comparison with Kapandji scores

The Kapandji score is used widely to record thumb opposition and is the only alternative to angular measurements. We aimed to verify the extent to which the Kapandji score reflects the angle of pronation. We recruited volunteers with unaffected upper limbs (33 hands) and patients with carpal tunnel syndrome (20 hands). We attached a small gyroscope to the thumb metacarpal and measured the pronation and palmar abduction angles at each position of the Kapandji score in both groups. The Kapandji score showed a strong ceiling effect, and the increase in angle size at each Kapandji score levelled off around a score of 6 in both groups. A Kapandji score greater than 6 does not necessarily reflect thumb opposition. Level of Evidence: III.

Three-dimensional functional workspace of thumb prehension

BACKGROUND

Clinical assessment of thumb motion is challenging, due to the complex anatomy and motion of the thumb. It is especially difficult to measure hand movement during activity, and to measure the effects of surgery that changes the morphology of the thumb. A three-dimensional model of the hand may enable clinicians to better assess prehension and thumb motion at baseline, and following surgical intervention.

METHODS

A kinematic model of the hand was developed to measure thumb and finger position during functional tasks, enabling the calculation of the volume of space in which prehension could occur. This method was validated by application to a mechanical model of the hand, and then applied to ten adult participants, using three-dimensional motion analysis with a marker array developed for the purpose of this study.

FINDINGS

This method can be used to accurately measure three-dimensional thumb joint range of motion (RoM) and predicted functional workspace during functional activities. The thumb carpometacarpal joint was predominantly responsible for thumb position during functional tasks. Predicted functional workspace is proportional to hand morphometric measurements.

INTERPRETATION

A kinematic model of the hand measures thumb RoM and predicts functional workspace during functional activities.

A new method of measuring the thumb pronation and palmar abduction angles during opposition movement using a three-axis gyroscope

Background

Thumb opposition is vital for hand function and involves pronation and palmar abduction. The improvement of pronation is often used as one of the evaluation items of the opponensplasty method for severe carpal tunnel syndrome. However, most of the studies used substitution evaluation methods for measurement of the pronation angle. Thus, there is still no appropriate method for measuring thumb pronation angle accurately in carpal tunnel syndrome patients.

In recent reports, a wearable gyroscope was used to evaluate upper extremity motions and it can be possibly used for accurate measurement of the thumb pronation angle along the three-dimensionally moving bone axis.

Thus, we investigated the reliability of measuring thumb pronation using a gyroscope and evaluated whether this method can be used to detect opposition impairment.

Methods

The participants were volunteers with unaffected upper limbs (32 hands) and patients with carpal tunnel syndrome (27 hands). The pronation and palmar abduction angles during opposition movements were measured using a three-axis gyroscope that included a three-axis accelerometer. The gyroscope was fixed onto the first metacarpal bone and the thumb phalanx.

Results

The pronation and palmar abduction angles of the metacarpal bone and the palmar abduction angles of the phalanx significantly decreased in the carpal tunnel syndrome group. The pronation angle of the metacarpal bone during opposition movement peaked later than the palmar abduction angle in all hands.

Conclusions

We were able to measure the thumb pronation and palmar abduction angles using the three-axis gyroscope, and this tool was able to detect impairments of thumb opposition due to carpal tunnel syndrome. This could be a tool for measuring thumb and finger angles and for detecting impairments caused by various diseases.

HyPro: A Multi-DoF Hybrid-Powered Transradial Robotic Prosthesis

This paper proposes a multi-DoF hybrid-powered transradial robotic prosthesis, named HyPro. The HyPro consists of two prosthetic units: hand and wrist that can achieve five grasping patterns such as power grasp, tip grasp, lateral grasp, hook grasp, and index point. It is an underactuated device with 15 degrees of freedom. A hybrid powering concept is proposed and implemented on hand unit of HyPro where the key focus is on restoration of grasp functions of biological hand. A novel underactuated mechanism is introduced to achieve the required hand preshaping for a given grasping pattern using electric power in the pregrasp stage and body power is used in grasp stage to execute the final grasping action with the selected fingers. Unlike existing hybrid prostheses where each of the joints is separately controlled by either electric or body power, the proposed prosthesis is capable of delivering grasping power in combination. The wrist unit of HyPro is designed and developed to achieve flexion-extension and supination-pronation using electric power. Experiments were carried out to evaluate the functionality and performance of the proposed hybrid-powered robotic prosthesis. The results verified the potential of HyPro to perform intended grasping patterns effectively and efficiently.

Long-Term Outcomes of Huber Opposition Transfer for Augmenting Hypoplastic Thumb Function

PURPOSE

This study was conducted to report the functional outcomes of the Huber opposition transfer (abductor digiti minimi muscle) in types II and IIIA hypoplastic thumbs.

METHODS

Patients who had undergone a Huber opposition transfer with at least 5 years of follow-up were included in this study. There were 21 thumbs included; 12 returned for a detailed evaluation and 9 were included with a medical record review. Outcome measures included range of motion and pinch strength; Pediatric Outcomes Data Collection Instrument (PODCI) and Patient-Reported Outcomes Measurement Information System (PROMIS) scores were collected on those who could return. There were 15 type II and 6 type IIIA thumbs.

RESULTS

Range of motion was significantly less than normal for both the interphalangeal and the metacarpophalangeal joints. For the returning cohort, key and tripod pinch were 44% and 65% of normal. The median Kapandji score was 9 (range, 6-10). The PODCI scores were high for global, upper extremity function, happiness, and pain. The PROMIS scores were similar to normal, except for parent reports of physical function. For all included patients, there was a revision surgery rate of 22%, primarily related to persistent instability.

CONCLUSIONS

At a minimum 5-year follow-up, the Huber opposition transfer for types II and IIIA thumbs was shown to provide good subjective outcomes, despite limited range of motion and strength.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Inter-rater and inter-instrument reliability of goniometric thumb active and passive flexion range of motion measurements in healthy hands

Introduction

Goniometry is a common measure of range of motion and may be assessed by different therapists and goniometers. To date, there is limited psychometric data on active and passive range of motion measurements of individual thumb joints. The purpose of this study was to analyze inter-rater and inter-instrument reliability of passive and active flexion goniometric measures of thumb joints in healthy adults.

Methods

A within-subjects psychometric design was utilized. Two raters each used two goniometers (Baseline™ Flexion-Hyper Extension and Baseline™ 180 Degree Digit) to measure each participant’s (n = 48) thumb carpometacarpal, metacarpophalangeal, and interphalangeal flexion range of motion. Inter-rater and inter-instrument reliability and stability were evaluated through use of intraclass correlation coefficient, standard error of the measurement, and minimal detectable change test statistics.

Results

Inter-rater reliability was poor for carpometacarpal flexion and good-to-excellent for metacarpophalangeal and IP flexion. Between-rater error ranged between 3.9 and 6.3 degrees for active measurements and between 3.9 and 7.9 degrees for passive. Error was generally less when using the Baseline™ 180 Degree Digit goniometer. Inter-instrument reliability was excellent for all joints.

Discussion

These findings validate the concerns that thumb goniometry inter-rater reliability may differ in clinical and non-clinical populations, support further study in clinical populations, and support a common assumption that the same rater should test the same client with the same goniometer to minimize measurement error. When compared to the Baseline™ Flexion-Hyper Extension Goniometer, the Baseline™ 180 Degree Digit had higher repeatability across raters. Further research on within-rater reliability is required as is study on clinical populations.

Arthroscopic Resection of Distal Pole of the Scaphoid for Scaphotrapeziotrapezoid Joint Arthritis: Comparison between Simple Resection and Implant Interposition

BACKGROUND

Isolated scaphotrapeziotrapezoid is a relatively rare condition, and there is still not complete consensus on the treatment of this pathology.

PURPOSE

The aim of the present study is to assess the utility of implant interposition after arthroscopic scaphoid distal pole resection for scaphotrapeziotrapezoid arthritis.

MATERIAL AND METHODS

The authors present a prospective study after the arthroscopic resection of the distal pole of the scaphoid in 24 patients. In a group of 11 patients, the simple resection was performed while in the other 13 patients the scaphoid resection and pyrocarbone implant interposition.

RESULTS

All patients were clinically evaluated with disability of arm, shoulder, hand score. Dorsal intercalated segment instability deformity was also measured from X-ray analysis. Grip and pinch strength were measured too, and patients were also given a visual analog scale questionnaire. Both clinical and radiographic assessments were done at 24 months postoperatively.

CONCLUSIONS

The study showed comparable results with both the techniques.

LEVEL OF EVIDENCE II

A prospective comparative study.

Measuring thumb range of motion in first carpometacarpal joint arthritis: The inter-rater reliability of the Kapandji Index versus goniometry

Introduction

Goniometric measurement of thumb range of motion is often used as an outcome measure in assessing patients with first carpometacarpal osteoarthritis. Despite common use and demonstrated construct validity, the reliability of this technique has not been well established. The Kapandji Index is an alternate functional measure of thumb motion suitable for use with this client group. The purpose of this study was to examine the inter-rater reliability of the goniometric measures for thumb joint range of motion compared to the Kapandji Index in patients with first carpometacarpal joint osteoarthritis.

Methods

Two independent assessors, who were blind to each other’s measurements, measured thumb range of motion in 33 patients (54 thumbs). All participants were undergoing treatment for carpometacarpal joint osteoarthritis. Active range of motion was measured with a goniometer for all the thumb joints using a standardised measurement protocol. The Kapandji Index score was recorded. Relative reliability was assessed by using the intraclass correlation coefficient. Absolute reliability was also calculated by determining the standard error of measurement (SEM68) and the minimal detectable difference (MDD90).

Results

Inter-rater reliability for the goniometer was highly variable ranging from poor to excellent (intraclass correlation coefficient 0.128–0.860). The SEM68 ranged from 9° to 13°, and the resulting MDD90 varied from 21° to 31° for the different thumb joints. The Kapandji Index had excellent inter-rater reliability among the different raters (intraclass correlation coefficient 0.772–0.917).

Conclusions

Measurement of goniometric active range of motion of the thumb may have limited utility as a measure of clinical effectiveness for patients with carpometacarpal joint osteoarthritis. However, the Kapandji Index is a reliable measure of functional range of motion.