Injury Risk Functions for the Midsized Male Wrist and Elbow as a Result of Behind Shield Blunt Trauma.

Ballistic shields protect users from a variety of threats, including projectiles. Shield back-face deformation (BFD) is the result of the shield deflecting or absorbing a projectile and deforming toward the user. Back-face deformation can result in localized blunt loading to the upper extremity, where the shield is supported by the user. Two vulnerable locations along the upper extremity were investigated-the wrist and elbow-on eight postmortem human subjects (PMHS) using a pneumatic impacting apparatus for investigating the fracture threshold as a result of behind shield blunt trauma (BSBT). Impacting parameters were established by subjecting an augmented WorldSID anthropomorphic test device (ATD) positioned behind a ballistic shield to ballistic impacts. These data were used to form the impact parameters applied to PMHS, where the wrist most frequently fractured at the distal radius and the elbow most frequently fractured at the radial head. The fracture threshold for the wrist was 5663±1386 N (mean±standard deviation), higher than the elbow at 4765±894 N (though not significantly, p = 0.15). The failure impact velocity for wrist impacts was 17.7±2.1 m/s, while for the elbow, the failure impact velocity was 19.5±0.9 m/s. An approximate 10% risk of fracture threshold was identified on the modified WorldSID ATD (no flesh analogue included) to inform future protective standards.

Prognostic factors for clinical outcomes after arthroscopic treatment of traumatic central tears of the triangular fibrocartilage complex.

Aims: The study aimed to assess the clinical outcomes of arthroscopic debridement and partial excision in patients with traumatic central tears of the triangular fibrocartilage complex (TFCC), and to identify prognostic factors associated with unfavourable clinical outcomes. Methods: A retrospective analysis was conducted on patients arthroscopically diagnosed with Palmer 1 A lesions who underwent arthroscopic debridement and partial excision from March 2009 to February 2021, with a minimum follow-up of 24 months. Patients were assessed using the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire, Mayo Wrist Score (MWS), and visual analogue scale (VAS) for pain. The poor outcome group was defined as patients whose preoperative and last follow-up clinical score difference was less than the minimal clinically important difference of the DASH score (10.83). Baseline characteristics, arthroscopic findings, and radiological factors (ulnar variance, MRI, or arthrography) were evaluated to predict poor clinical outcomes. Results: A total of 114 patients were enrolled in this study, with a mean follow-up period of 29.8 months (SD 14.4). The mean DASH score improved from 36.5 (SD 21.5) to 16.7 (SD 14.3), the mean MWS from 59.7 (SD 17.9) to 79.3 (SD 14.3), and the mean VAS pain score improved from 5.9 (SD 1.8) to 2.2 (SD 2.0) at the last follow-up (all p < 0.001). Among the 114 patients, 16 (14%) experienced poor clinical outcomes and ten (8.8%) required secondary ulnar shortening osteotomy. Positive ulnar variance was the only factor significantly associated with poor clinical outcomes (p < 0.001). Positive ulnar variance was present in 38 patients (33%); among them, eight patients (21%) required additional operations. Conclusion: Arthroscopic debridement alone appears to be an effective and safe initial treatment for patients with traumatic central TFCC tears. The presence of positive ulnar variance was associated with poor clinical outcomes, but close observation after arthroscopic debridement is more likely to be recommended than ulnar shortening osteotomy as a primary treatment.

Does Immobilization of Distal Radius Torus Fractures Affect Treatment Outcome?

OBJECTIVE: The aim of this study is to compare the clinical results of splint, short arm circular plaster, and soft bandage immobilization methods applied in the treatment of wrist torus fractures in a single center. METHODS: Patients treated for torus fractures at a tertiary trauma hospital between January 2018 and January 2022 were analyzed retrospectively. According to the physician's preference, a splint, short arm circular plaster, or soft bandage was applied to each patient. The treatment modalities, the number of hospital admissions during the treatment, the number of radiological imaging procedures used during the treatment, immobilization time, and the follow-up periods of the patients were checked and noted on the hospital data processing system. RESULTS: Six hundred ten patients were included in the study. It was determined that 351 patients were treated with a short arm splint, 155 with a short arm circular cast, and 104 with soft bandaging. The number of radiological imaging procedures, the number of hospital admissions during the treatment, the duration of the pain complaint, and the complication rate of the patients treated with splint were significantly lower than the groups treated with short arm circular plaster and soft bandage (P < 0.001). CONCLUSIONS: It was observed that patients who were immobilized with a short arm splint required less follow-up time and fewer imaging procedures and hospital admissions and experienced earlier pain relief and lower complication rates. We think that the use of short arm splints in the treatment of torus fractures is sufficient, safe, and advantageous.

[Sport Injuries to Wrist and Fingers].

INTRODUCTION: About one fifth of all sports accidents involve the hand. Many injuries can be diagnosed and treated easily. However, some of them such as fractures of the scaphoid or the hamate of the hamulus are difficult to detect with conventional radiographs and are often missed without a CT scan. Ligament injuries such as the skier's thumb must be recognized and treated properly, often surgically. There are also sport-specific injuries, such as the closed rupture of a flexor tendon pulley in climbers, which otherwise occur rarely and are little known. These topics, pitfalls and tricks will be discussed.

[Clinical effect of the giant deep inferior epigastric artery paraumbilical perforator flap in repairing the circular high-voltage electric burn wounds on the wrist].

Objective: To investigate the clinical effect of the giant deep inferior epigastric artery paraumbilical perforator flap in repairing the circular high-voltage electric burn wounds on the wrist. Methods: A retrospective observational study method was used. From September 2016 to October 2021, thirteen male patients (aged 20-43 years) with annular high voltage (10-100 kV) electrical burns on the wrist were admitted to the Beijing Jishuitan Hospital. At the early stage after injury, the patient's wrist was subjected to incision, tension reduction and debridement, with the wound area after debridement being 27 cm×16 cm-32 cm×19 cm; in 12 patients with vascular injury, the radial or ulnar artery was reconstructed by great saphenous vein transplantation, with the length of 15-25 cm; the wrist wound was repaired by free transplantation of the deep inferior epigastric artery paraumbilical perforator flap (if the wound was giant, the lower abdominal flap carrying other perforators was used), with the area of 30 cm×19 cm-35 cm×20 cm. The donor site was repaired by direct suture+skin grafting or relay flap transplantation. After surgery, the survival of flap in recipient area, as well as survival of the skin or flap in donor site were observed. During follow-up, the appearances of the flap in recipient area and the recovery of hand function, as well as the healing of donor site, occurrence of abdominal wall hernia, and scar in skin graft area were observed. Results: After surgery, all the 13 patients' paraumbilical perforator flaps survived. Among them, 3 patients had subcutaneous fat necrosis at the distal end of the wrist flap, and the wound had mild infection, which healed after re-expansion and dressing change. All the skin grafts in the donor site of 10 patients survived, and the flaps in the donor site of 3 patients survived well. The patients were followed up for 6 months to 3 years. The flaps in recipient area were in good shape, 8 cases had partial recovery of hand function, and 5 cases had loss of finger flexion function; the donor site of abdominal flap healed well with no abdominal hernia occurred, and the skin graft site had no obvious scar hyperplasia and was soft in texture. Conclusions: Early vascular reconstruction after injury, together with free transplantation of the giant deep inferior epigastric artery paraumbilical perforator flap are effective in repairing circular high-voltage electrical burn wounds on the wrist.

Wrist Injuries in Climbers.

BACKGROUND: Acute and chronic injuries to the wrist are among the most common sport-related complaints of climbing athletes but have not been extensively evaluated in this population. Therefore, it is important to categorize climbing injuries to the wrist, analyze risk factors, and assess treatment outcomes. PURPOSE: To evaluate the distribution, outcomes, and influencing factors of wrist injuries in climbers. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Climbing athletes with wrist injuries who presented to our specialized sports medical center over the course of 4 years (2017-2020) were selected. All had prospectively completed questionnaires including their climbing-specific background (years of training, climbing level, training methods, etc). Injuries were analyzed (International Climbing and Mountaineering Federation [UIAA] grade and diagnosis), and treatment methods and outcomes were retrospectively assessed with a minimum follow-up of 2 years. Parameters included the climbing score, visual analog scale for pain score, Patient-Rated Wrist Evaluation (PRWE) score, and shortened version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score including the sport component (DASH-Sport) score before and after treatment as well as time to return to climbing. RESULTS: A total of 69 patients (25 female, 44 male) with 78 wrist injuries were identified and analyzed. Of these, 7 injuries were bilateral, occurring at the same time, and 2 injuries were independent reinjuries to either the same or the contralateral side. In addition, 24 injuries (30.8%) were acute, while 54 (69.2%) were chronic. Overall, 2 injuries had a UIAA grade of 3; all others had a UIAA grade of 2. The most frequent injuries were synovitis of the ulnocarpal recess, ulnar impaction, bone marrow edema of the lunate, wrist sprains (joint capsular pain with stress, with no pathological finding on magnetic resonance imaging), and wrist ganglion cysts. Nonoperative treatment was performed for 61 of the injuries, while 17 were treated surgically. In 51 cases (65.4%), injuries healed without consequences; in 27 cases (34.6%), discomfort remained. The visual analog scale pain score decreased from 4.8 ± 1.9 before treatment to 0.7 ± 1.0 after treatment (P < .001), the PRWE score decreased from 53.6 ± 24.9 to 10.3 ± 13.1 (P < .001), the QuickDASH score improved from 53.0 ± 16.6 to 20.0 ± 20.2 (P < .001), and the DASH-Sport score improved from 82.0 ± 16.1 to 38.1 ± 23.5 (P < .001). The climbing score improved from 2.5 ± 1.1 to 4.3 ± 1.0 points (P < .001). The patient-reported number of days with pain was negatively correlated with changes in the PRWE score (r = -0.351; P < .001), QuickDASH score (r = -0.316; P = .007), and climbing score (r = -0.264; P = .025) as well as the number of days without climbing (r = -0.266; P = .025). The number of days without climbing was positively correlated with changes in the PRWE score (r = 0.369; P < .001). CONCLUSION: Wrist injuries in climbers constituted a diverse set of diagnoses. Ulnar-sided injuries were most common, and many patients had >1 diagnosis. Outcomes for all treatment methods (surgery and nonoperative care) were favorable, but approximately one-third of climbers had persistent wrist discomfort after treatment, underscoring the need for accurate diagnoses and acute and expert care.

Hand and Wrist Injuries Associated With Application of Physical Restraints: A Systematic Review.

While handcuffs and zip ties are common methods of physical restraint used by law enforcement, they have been noted to damage soft tissue and bony structures of the hand and wrist. This paper seeks to characterize the safety of physical restraints by summarizing its effects on hand and wrist function and disability. Relevant studies were gathered through an independent double selection and extraction process using 3 electronic databases (EMBASE, MEDLINE, and CINAHL) from database inception to June 19, 2020. A total of 16 studies involving 807 participants were included. Lesion to the superficial branch of the radial nerve was the most commonly reported injury noted in 82% (42/55) of hands examined. A total of 6% (5/77) of examined hands had bony injury, including 3 radial styloid fractures and 2 scaphoid fractures. Both studies on zip ties noted presence of handcuff neuropathy, with 1 case report documenting severe rapidly progressing ischemic monomelic neuropathy. Overall, the use of handcuffs and zip ties is associated with entrapment neuropathies and bony injury to the hand and wrist. Further studies of higher quality evidence are necessary to understand the effects of physical restraint on hand function and disability.

Investigating Patient-Level Radiation Exposure in Hand and Wrist Fracture Surgery.

BACKGROUND: Although occupational exposure to radiation has been previously studied in the hand surgery literature, there is a paucity of studies looking at radiation exposure to the patient during fluoroscopy-guided hand surgery. We aimed to describe the level of radiation experienced by patients undergoing common hand and wrist fracture fixation and to identify risk factors for increased radiation exposure. METHODS: We performed a retrospective review of patients at a single institution who underwent fracture fixation of the hand, wrist, or forearm requiring mini c-arm fluoroscopic guidance from 2016 to 2020. Data points collected included patient demographics, procedural details, and indicators of radiation exposure including dose-area product (DAP), total intraoperative images, and total fluoroscopy time. Effective dose (ED) was calculated using DAP, field size, and a previously established conversion factor. RESULTS: The final sample included 361 patients with an average age of 46 years. Procedures included fixation of forearm fractures (3.3%), distal radius fractures (35.7%), metacarpal fractures (30.8%), and phalangeal fractures (30.2%). The median number of intraoperative images acquired was 36, median total fluoroscopy time was 43 seconds, median DAP was 4.8 cGycm2, and median ED was 0.13 µSv. Distal (metacarpal and phalangeal) fractures required more intraoperative images and longer total fluoroscopy time (49 images, 61 seconds) compared with proximal (forearm and distal radius) fractures (39 images, 47 seconds) (images, P = 0.004; exposure time, P = 0.004). However, distal fractures had a lower average ED compared with proximal fractures (0.15 vs 0.19 µSv, P = 0.020). When compared with open procedures, percutaneous procedures had higher DAPs (8.8 vs 4.9 cGycm2, P < 0.001), higher ED (0.22 vs 0.15 µSv, P < 0.001), more intraoperative images (65 vs 36 images, P < 0.001), and longer total fluoroscopy time (81.9 vs 44.4 seconds, P < 0.001). CONCLUSIONS: Patient-level radiation exposure during fluoroscopy-guided hand and wrist procedures is low relative to other common imaging modalities, such as dental radiographs, chest x-rays, and computed tomography scans, and is comparable with less than a few hours of natural background radiation exposure, highlighting the overall safety of this important technology. Further study should be performed to establish reference ranges, which could lead to improved patient counseling and evidence-based guidelines on patient shielding.

[The incidence of hand trauma the COVID-19 epidemic setting]. / L'incidence des traumatismes de la main dans le contexte épidémique COVID-19.

OBJECTIVES: In France, a lockdown was enforced from March 17 to May 11, 2020. It was renewed with different modalities from April 3 to May 3, 2021. Our objective was to compare the epidemiology of hand and wrist trauma injuries during these periods to a control period, with the hypothesis of a decreased incidence of hand and wrist trauma. METHODS: Patients consulting at a trauma emergency center of a university hospital labeled SOS-Mains were included during lockdowns, and were compared with a control group who consulted during an equivalent period in 2019. We retrospectively collected demographic and clinical data in relation to hand and wrist injuries. RESULTS: During lockdowns, there was an increase in these injuries relative to the total number of patients (from 16% to 22% and 18%). We found a decrease during the first lockdown in the number of fractures, amputations, burns, infections, injuries secondary to a work accident and isolated wounds but a significantly higher proportion of tendon and vasculonervous injuries in the first lockdown (12% vs. 4%). CONCLUSIONS: In first lockdown, the incidence of hand and wrist injuries decreased, but there was an increase in tendon and microsurgical injuries. This may be explained by the change in leisure activities. This underlines the importance of preventive measures concerning the risks related to some activities (use of sharp/motorized tools) in this context of health crisis.

Baseball Injuries of the Hand and Wrist.

Injuries of the hand and wrist are common in baseball. Because of the unique motions and loads encountered in this sport, physicians treating baseball players may encounter hand and wrist injuries ranging from common to rare. An understanding of these baseball-related injuries must include their pathoanatomy, diagnosis, and treatment options. This knowledge is critical for the general orthopaedic surgeon treating baseball players to allow for timely and appropriate treatment. This article reviews the pathophysiology, diagnosis, and treatment of baseball-related hand and wrist injuries, with a target audience of general orthopeadic surgeons.

[A painful, swollen wrist after a fall from a bicycle]. / Een pijnlijke, gezwollen pols na een val van de fiets.

This case concerns a male with a painful and swollen wrist after a fall from a bicycle. Physical examination of the wrist showed medial nerve compression. Radiographic analyses showed a lunate dislocation. A lunate dislocation is an often missed diagnosis, resulting in a delay in treatment and worse outcome.

The effect of COVID-19 on a Major Trauma Network. An analysis of mechanism of injury pattern, referral load and operative case-mix.

PURPOSE: The aim of this study was to evaluate changes in both mechanism and diagnoses of injuries presenting to the orthopaedic department during this lockdown period, as well as to observe any changes in operative case-mix during this time. METHODS: A study period of twelve weeks following the introduction of the nationwide "lockdown period", March 23rd - June 14th, 2020 was identified and compared to the same time period in 2019 as a "baseline period". A retrospective analysis of all emergency orthopaedic referrals and surgical procedures performed during these time frames was undertaken. All data was collected and screened using the 'eTrauma' management platform (Open Medical, UK). The study included data from a five NHS Foundation Trusts within North West London. A total of 6695 referrals were included for analysis. RESULTS: The total number of referrals received during the lockdown period fell by 35.3% (n=2631) compared to the same period in 2019 (n=4064). Falls remained proportionally the most common mechanism of injury across all age groups in both time periods. The proportion sports related injuries compared to the overall number of injuries fell significantly during the lockdown period (p<0.001), however, the proportion of pushbike related accidents increased significantly (p<0.001). The total number of operations performed during the lockdown period fell by 38.8% (n=1046) during lockdown (n=1732). The proportion of patients undergoing operative intervention for Neck of Femur (NOF) and ankle fractures remained similar during both study periods. A more non-operative approach was seen in the management of wrist fractures, with 41.4% of injuries undergoing an operation during the lockdown period compared to 58.6% at baseline (p<0.001). CONCLUSION: In conclusion, the nationwide lockdown has led to a decrease in emergency orthopaedic referrals and procedure numbers. There has been a change in mechanism of injuries, with fewer sporting injuries, conversely, there has been an increase in the number of pushbike or scooter related injuries during the lockdown period. NOF fractures remained at similar levels to the previous year. There was a change in strategy for managing distal radius fractures with more fractures being treated non-operatively.

Pisiform dislocation.

A pisiform dislocation is an uncommon injury which can lead to significant morbidity if missed. The literature regarding pisiform dislocation is limited and largely from case reports. In this case, we present a 51-year-old right-hand dominant male who sustained the injury after a fall. He attended the emergency department on the same day and a closed reduction was able to be performed under a haematoma block. On review in follow-up clinic the patient's symptoms had completely resolved.

Forensic evaluation of alleged wrist restraint/handcuff injuries in survivors of torture utilizing the Istanbul Protocol.

Despite being a common form of abuse, there is a paucity of literature describing shackling and wrist restraint injuries among survivors of torture. Forensic evaluation of alleged wrist restraint/handcuff injuries in survivors of torture presents challenges to the evaluator, especially if the injuries are remote and do not leave lasting marks nor neurologic deficits. Thorough history-taking and physical examination are critical to effective forensic documentation. Guidance is provided in The Manual on Effective Investigation and Documentation of Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment (Istanbul Protocol), the gold standard for the medicolegal documentation of torture. This guidance relies primarily on physical findings, with less direction provided on how to interpret historical evidence or when historical evidence provided by the patient can be interpreted as highly consistent with alleged injury in the absence of current physical findings. Through a case-based review, we present diagnostic strategies for the evaluation of alleged abuse involving wrist restraints/handcuffs, focusing on skin, neurologic, and osseous injuries. We highlight key findings from both the history and physical examination that will allow the evaluator to improve the accuracy of their expert medical opinion on the degree to which medical findings correlate with the patient's allegations of wrist restraint injuries.

Epidemiology and Impact of Hand and Wrist Injuries in Major and Minor League Baseball.

Background: Professional baseball players are at risk of acute and chronic injuries to their upper extremities. Methods: Major League Baseball's Health and Injury Tracking System, a prospective injury surveillance system, was used to identify and characterize all hand and wrist injuries sustained by all Major League Baseball (MLB) and Minor League Baseball (MiLB) players during the pre-, regular, and postseason throughout 2011-2016. Injuries were included if they resulted in at least 1 day out of play and were sustained during standard baseball activities. Days missed were defined as the time between injury and the first time in which a player was cleared to return to play. Results: During the study period, there were 4478 hand and 1748 wrist injuries throughout MLB and MiLB, which resulted in a total of 105 246 days out of play. This was equivalent to the length of 575 individual MLB player seasons, and the mean days missed per injury was 17 days. Most injuries were traumatic in nature, with 43% (n = 2672) of players injured after being hit by a baseball that mainly occurred during batting (n = 2521; 40%). Injuries that most frequently required surgical intervention were hook of hamate fractures (72%) and scaphoid fractures (60%). Conclusions: Understanding the epidemiology and impact of hand and wrist injuries in MLB and MiLB players may lead to improved management of these injuries and reduce time away from play. Most importantly, preventive measures and/or enhanced protective gear may be developed to minimize these types of injuries in MLB and MiLB.

Semiquantitative single-photon-emission computed tomography /computed tomography study to evaluate concomitant ulnar impaction syndrome in patients presenting with triangular fibrocartilage complex tears.

INTRODUCTION: Patients presenting with tears of the triangular fibrocartilage complex (TFCC) can have ulnar positive variance, for which the clinical relevance to concomitant ulnar impaction syndrome (UIS) may be unclear. We hypothesized that maximum standardized uptake value (SUVmax), a semiquantitative single-photon-emission computed tomography/computed tomography (SPECT/CT) value, would distinguish between the traumatic TFCC tear and degenerative TFCC tear associated with the UIS. This study aimed to compare SUVmax between patients with TFCC tear only and patients with TFCC tear and UIS. METHODS: A total of 26 patients presenting with TFCC tears on magnetic resonance imaging (MRI) underwent semiquantitative SPECT/CT examinations. The diagnosis of concomitant UIS was made based on positive ulnar impaction tests and MRI findings. We compared the SUVmax between patients with and without concomitant UIS. We also calculated the cutoff value for the diagnosis of UIS using receiver operating characteristic curve analysis. RESULTS: Of 26 patients, 14 had concomitant UIS, and 12 had TFCC tears only. The SUVmax was significantly higher in patients with concomitant UIS than in those without UIS (p = 0.048). With a SUVmax cutoff value of 4.09 for UIS, sensitivity of 67% and specificity of 82% were obtained. CONCLUSIONS: In the semiquantitative SPECT/CT examinations of patients with TFCC tears, those with concomitant UIS had a higher SUVmax than those without UIS. Semiquantitative SPECT/CT can be helpful in confirming concomitant UIS in patients with TFCC tears.

The Weekend Warrior: Common Hand and Wrist Injuries in Athletes.

Weekend warriors are individuals who condense their weekly physical activity into extended intervals over one or two days.1 Excessive physical activity can result in a multitude of overuse and traumatic upper extremity injuries. The purpose of this review is to highlight the etiology and management of the more common hand and wrist injuries in athletes.

Gymnast's Wrist (Distal Radial Physeal Stress Syndrome).

The distal radial physis is a common site for injury in gymnasts because of the significant amount of load applied during upper extremity weight-bearing. Wrist pain has been reported in up to 88% of gymnasts. The long-term consequences of overuse wrist injuries, such as distal radial physeal arrest, include degenerative conditions that often cause pain and functional limitations. In the more immediate stage of many overuse injuries, early diagnosis can promote quicker care and recovery and thus faster return to play. Less time lost to injury can be very important in maintaining an athlete's quality of life.

The correlation between shape of the sigmoid notch of the distal radius and the risk of triangular fibrocartilage complex foveal tear.

AIMS: The aim of this study was to analyze the association between the shape of the distal radius sigmoid notch and triangular fibrocartilage complex (TFCC) foveal tear. METHODS: Between 2013 and 2018, patients were retrospectively recruited in two different groups. The patient group comprised individuals who underwent arthroscopic transosseous TFCC foveal repair for foveal tear of the wrist. The control group comprised individuals presenting with various diseases around wrist not affecting the TFCC. The study recruited 176 patients (58 patients, 118 controls). The sigmoid notch shape was classified into four types (flat-face, C-, S-, and ski-slope types) and three radiological parameters related to the sigmoid notch (namely, the radius curvature, depth, and version angle) were measured. The association of radiological parameters and sigmoid notch types with the TFCC foveal tear was investigated in univariate and multivariate analyses. Receiver operating characteristic curves were used to estimate a cut-off for any statistically significant variables. RESULTS: Univariate analysis showed that the flat-face type was more prevalent in the patients than in the control group (43% vs 21%; p = 0.002), while the C-type was lower in the patients than in the control group (3% vs 17%; p = 0.011). The depth and version angle of sigmoid notch showed a negative association with the TFCC foveal tear in the multivariate analysis (depth: odds ratio (OR) 0.380; p = 0.037; version angle: OR 0.896; p = 0.033). Estimated cut-off values were 1.34 mm for the depth (area under the curve (AUC) = 0.725) and 10.45° for the version angle (AUC = 0.726). CONCLUSION: The proportion of flat-face sigmoid notch type was greater in the patient group than in the control group. The depth and version angle of sigmoid notch were negatively associated with TFCC foveal injury. Cite this article: Bone Joint J 2020;102-B(6):749-754.

Development of an ergonomic four-finger-push manual pipette design.

The purpose of this study was to develop a new pipette design in which the pipette is operated by four fingers, taking into account the anatomy and anthropometry of the hand. The proposed new pipette designs were compared with a traditional thumb-push pipette based on muscle activity, wrist posture, subjective discomfort ratings for upper extremities, and user preference. The results of the study revealed that the four-finger, ergonomic pipette design reduced muscle exertion (25% reduction for aspiration and 35% reduction for dispensing), awkward wrist posture (33% reduction in wrist flexion, radial and ulnar deviation), and perceived discomfort in the wrist, hand and lower arm. Furthermore, most participants (9 of 10) who used a pipette in their daily work preferred the new pipette designs to a traditional thumb-push pipette design. Thus, we expect that this study will contribute to the reduction of WMSDs risk factors and pain.