Does a Modified Technique to Achieve Arthrodesis of the Wrist After Resection of the Distal Radius and Translocating the Ipsilateral Ulna as a Vascularized Graft to Reconstruct the Defect Improve Grip Strength and Outcomes Scores?

BACKGROUND: Ten years ago, we reported the results of a procedure in which we translocated the ipsilateral ulna as a vascularized autograft to reconstruct defects of the distal radius after tumor resection, with excellent functional results. At that time, wrist arthrodesis was achieved by aligning the translocated ulna with the scapholunate area of the carpus and usually the third metacarpal. This resulted in wrist narrowing. We then wondered if aligning the translocated ulna with the scaphoid and the second metacarpal would result in ulnar deviation and thereby improve grip strength. We believed lateralization would reduce the wrist narrowing that occurs with fusion to the third metacarpal and would make the cosmesis more acceptable. We also modified the incision to dororadial to make the scar less visible and thus improve the cosmesis. QUESTIONS/PURPOSES: (1) Is there an objective improvement in grip strength and functional scores (Musculoskeletal Tumor Society [MSTS] and Mayo wrist) when the translocated ulna is lateralized and the wrist is fused with the translocated ulna and aligned with the second metacarpal versus when the translocated ulna is aligned with the third metacarpal? (2) Did lateralization caused by the wrist fusion aligned with the second metacarpal minimize wrist narrowing as measured by the circumference compared with the fusion aligned with the third metacarpal? METHODS: From 2010 and 2018, we treated 40 patients with distal radius tumors at our institution, 30 of whom had a distal radius enbloc resection. Twenty-eight patients had an ipsilateral ulna translocation and wrist arthrodesis in which the radius and translocated ulna were aligned with either the second (n = 15) or the third (n = 13) metacarpals. Two patients in the second metacarpal group and three patients in the third metacarpal group were lost to follow-up before 24 months after surgery and were excluded. A retrospective analysis of 23 patients (20 with giant cell tumors and three with malignant bone tumors) included a review of radiographs and institutional tumor database for surgical and follow-up records to study oncologic (local disease recurrence), reconstruction (union of osteotomy junctions, implant breakage or graft fracture, and wrist circumference), and functional outcomes (MSTS and Mayo wrist scores and objective grip strength assessment compared with the contralateral side). The results were compared for each study group (second metacarpal versus third metacarpal). There was no difference in the incidence of local recurrence or the time to union between the two groups. There were no implant breakages or graft fractures noted in either group. RESULTS: Patients in the second metacarpal group lost less grip strength compared with the unoperated side in the third metacarpal group (median 12% [range -30% to 35%] versus median 28% [15% to 42%], difference of medians 16%; p = 0.006). There were no between-group differences in terms of MSTS (median 30 [24 to 30] versus median 26.5 [22 to 30], difference of medians 3.5; p = 0.21) or Mayo wrist scores (median 83 [65 to 100] versus median 72 [50 to 90], difference of medians 11; p = 0.10). The second metacarpal group also had less wrist narrowing as seen from the median difference in circumference between the operated and unoperated wrists (median narrowing 10 mm [3 to 35 mm] in the second metacarpal group versus median 30 mm [15 to 35 mm] in the third metacarpal group, difference of medians 20 mm; p = 0.04). CONCLUSION: Wrist arthrodesis after ulna translocation with alignment of the translocated ulna and the second metacarpal provides a functional position with ulnar deviation that offers some improvement in grip strength but no improvement in the MSTS or Mayo scores. Radialization/lateralization of the translocated ulna achieved from the alignment with the second metacarpal decreases the reduction in the wrist circumference and therefore reduces wrist narrowing. LEVEL OF EVIDENCE: Level III, therapeutic study.

Ultrasonography in Distal Ulnar Nerve Neuropathy: Findings in 33 Patients.

PURPOSE: Although there are many case reports on the role of ultrasonography (US) in distal ulnar nerve neuropathy (Guyon canal syndrome), there is a paucity of large series in the literature because of its rarity. During an 8-year period, 33 instances of electrodiagnostically confirmed cases underwent US imaging. These cases were analyzed to determine the role of US in uncovering the cause of distal ulnar nerve neuropathy and its contribution to further management. METHODS: This was a retrospective study of patients diagnosed with distal ulnar nerve neuropathy based on electrodiagnostic criteria, who also had undergone US (measurement of the cross-sectional area and documentation of causes such as cysts and neuromas). RESULTS: US showed normal ulnar nerve in 5, cysts in 10, neuromas in 2, and nonspecific enlargement in 16 patients. Surgery was performed in 15 patients, and the US findings were corroborated in those with cysts and neuromas; 1 patient had an aberrant muscle, and two had fibrous bands constricting the ulnar nerve in the Guyon canal (not detected preoperatively by US imaging). CONCLUSIONS: US imaging detected the underlying cause of distal ulnar nerve neuropathy in a significant percentage of patients, potentially contributing to effective treatment.

Wrist function recovery course in patients with scaphoid nonunion treated with combined volar bone grafting and a dorsal antegrade headless screw.

BACKGROUND: Surgical treatment is necessary for scaphoid nonunion. Open surgery with a combined volar and dorsal approach is thought to have poor functional outcomes and a prolonged recovery course. However, the detailed recovery course for this approach is rarely reported. The aim of this study was to investigate the recovery course and radiographic outcome for patients with scaphoid nonunion who underwent a combined volar bone grafting and dorsal antegrade headless screw approach. MATERIAL AND METHODS: Eighteen patients with scaphoid nonunion who underwent combined volar bone grafting and dorsal antegrade headless screw fixation were enrolled in this retrospective study. Preoperative and serial postoperative wrist functional and radiographic outcomes were collected and analysed. RESULTS: All 18 patients achieved bone union at a mean time of 14.3 weeks. Compared to the preoperative status, the grip strength, wrist motion arc, and Mayo Wrist score were improved significantly 6 months after surgery, whilst the Disabilities of the Arm, Shoulder, and Hand (DASH) score did not recover until 12 months after surgery. Significant improvements were found in all scaphoid radiographic parameters. CONCLUSION: The surgical outcomes for scaphoid nonunion treated with a combined volar bone grafting and dorsal antegrade headless screw achieved a high union rate, with great wrist functional and radiographic outcomes. The earliest recovered wrist functional parameters were grip strength, motion arc, Mayo Wrist score and finally the DASH score at postoperative 6 months and 12 months, respectively.

Wrist movements induce torque and lever force in the scaphoid: an ex vivo study.

PURPOSE: We hypothesised that intercarpal K-wire fixation of adjacent carpal bones would reduce torque and lever force within a fractured scaphoid bone. METHODS: In eight cadaver wrists, a scaphoid osteotomy was stabilised using a locking nail, which also functioned as a sensor to measure isometric torque and lever forces between the fragments. The wrist was moved through 80% of full range of motion (ROM) to generate torque and force within the scaphoid. Testing was performed with and without loading of the wrist and K-wire stabilisation of the adjacent carpal bones. RESULTS: Average torque and lever force values were 49.6 ± 25.1 Nmm and 3.5 ± 0.9 N during extension and 41 ± 26.7 Nmm and 8.1 ± 2.8 N during flexion. Torque and lever force did not depend on scaphoid size, individual wrist ROM, or deviations of the sensor versus the anatomic axis. K-wire fixation did not produce significant changes in average torque and lever force values except with wrist radial abduction (P = 0.0485). Other than wrist extension, torque direction was not predictable. CONCLUSION: In unstable scaphoid fractures, we suggest securing rotational stability with selected implants for functional postoperative care. Wrist ROM within 20% extension and radial abduction to 50% flexion limit torque and lever force exacerbation between scaphoid fragments.

Routine Health Outcome Measurement: Development, Design, and Implementation of the Hand and Wrist Cohort.

Routine measurement of outcome of clinical care is increasingly considered important, but implementation in practice is challenging. This article describes (1) how the authors created and implemented a routine outcome measurement cohort of patients with hand and wrist conditions and (2) how these data are used to improve the quality of care and facilitate scientific research. Starting in 2011, routine outcome measurement was implemented at all practice sites (currently 22) of a specialized treatment center for hand and wrist conditions across The Netherlands. The authors developed five "measurement tracks," including measurements administered at predetermined time points covering all hand and wrist disorders and treatments. An online system automatically distributes measurements among patients, which can be accessed by health care professionals. Using this system, the total number of yearly assigned tracks increased up to over 16,500 in 2018, adding up to 85,000 tracks in 52,000 patients in total. All surgeons, therapists, and other staff have direct access to individual patient data and patients have access to their treatment information using a secure patient portal. The data serve as a basis for studies on, among others, comparative effectiveness, prediction modeling, and clinimetric analyses. In conclusion, the authors present the design and successful implementation of a routine outcome measurement system that was made feasible using a highly automated data collection infrastructure, tightly linked to the patient journey and the workflow of health care professionals. The system serves not only as a tool to improve care but also as a basis for scientific research studies.

Functional outcome in giant cell tumor of distal radius treated with excision and fibular arthroplasty: a case series.

INTRODUCTION: Giant cell tumor (GCT) of bone is a locally aggressive benign neoplasm that is associated with a wide spectrum of biological activity ranging from latent benign to highly recurrent and has occasional metastatic potential. It affects the meta-epiphyseal region of long bones of young adults with most common site involved is the distal femur, followed by the distal radius. Plain radiographs and contrast-enhanced magnetic resonance imaging are the imaging modalities widely used followed by definite histopathology for diagnosis. Surgical treatment with curettage is considered optimal for local tumor control. Tumor excision with tumor-free margins is associated with lesser recurrence rates; however, for periarticular lesions this is usually accompanied with a suboptimal functional outcome. METHODS: Eleven eligible patients (all females, mean age 39.2 years) with Campanacci grade III GCT of the distal radius who were treated by en bloc resection and reconstruction with non-vascularized proximal fibular autografts at a single centre between July 2016 and December 2017 were included in the study. The patients had a clinical and radiographic review every month for the first 6 months, then biannually for minimum of 2 years. The functional, oncologic and radiological outcomes of the patients were analyzed and recorded. RESULTS: The mean duration of follow-up was 31.9 months. Bony union was achieved in all cases. The mean VAS score at 6 months was 1.1 (range 0-2). The mean Mayo Wrist score was 66.36 (range 55-80) with mean MSTS score was 21.09 (range 18-24). The average range of motion of the wrist was: 37.3° ± 6.9° of flexion, 47.1° ± 7.5° of extension, 57.3° ± 7.8° of supination and 63.6° ± 6.4° of pronation. The average graft length used was 15.6 cm. The complications noted were lung metastases which developed preoperatively, local site recurrence, wrist joint subluxation, foot drop and wound complication. DISCUSSION AND CONCLUSIONS: The primary aim of treating GCT distal radius is oncologically sound resection with good functional outcome and cosmesis being secondary. Reconstruction with a non-vascularized proximal fibular autograft is a reasonable option after en bloc resection of the distal radius for giant cell tumor of bone having comparable results with other treatment modalities.

Comparison of two approaches for carpal tunnel release: Extended versus mini-open technique.

OBJECTIVES: This study aims to describe a retrospective study using prospectively gathered data to compare mini-open and extended open release techniques for moderate to severe carpal tunnel syndrome (CTS). PATIENTS AND METHODS: The data of 198 consecutive patients (139 males, 59 females; mean age 57.0±4.5 years; range, 44 to 75 years) treated for CPS were used. For matching, age, gender and severity of the compression, the Greathouse Ernst Halle Schaffer neurophysiological classification system was used. After matching, 63 observations in each group (group 1: mini-open and group 2: extended open) were used for analysis. A Jamar hydraulic hand dynamometer was used to measure pre- and postoperative third month grip strengths. The key pinch test was performed also at third month. Patients completed the Boston Carpal Tunnel Questionnaire at the last follow-up. RESULTS: Symptom severity and functional status were improved up to half fold in both groups at final follow-up; however, there was no statistically significant clinical difference between the groups (p>0.05). There were totally six patients with paresthesia symptoms (three in each group; 4.7%), which improved in three months. Eight patients (6.3%, one in group 1 and seven in group 2, p=0.032) had dysesthesia and pillar pain. CONCLUSION: Mini-open and extended open carpal tunnel release have similar clinical outcomes without any major complications.

Operative Treatment is Not Associated with More Relief of Depression Symptoms than Nonoperative Treatment in Patients with Common Hand Illness.

BACKGROUND: Depression symptoms are prevalent in the general population, and as many as one in eight patients seeing a hand surgeon may have undiagnosed major depression. It is not clear to what degree lower mood is the consequence or cause of greater symptoms and limitations. If depressive symptoms are a consequence of functional limitations, they might be expected to improve when pathophysiology and impairment are ameliorated. Because surgical treatment is often disease-modifying or salvage, surgery might have a greater impact than nonoperative treatment, which is more often palliative (symptom relieving) than disease-modifying. QUESTIONS/PURPOSES: (1) For which hand or wrist conditions are depression symptoms lower after operative compared with nonoperative treatment? (2) Among the subset of patients with the highest depression scores, are depression symptoms lower after operative treatment compared with nonoperative treatment? (3) Among the subset of patients who had nonoperative treatment, are depression symptoms lower after a corticosteroid injection compared with no specific biomedical intervention? METHODS: At an academic orthopaedic department, 4452 patients had a new office visit for carpal tunnel syndrome, benign neoplasm, primary hand osteoarthritis, de Quervain's tendinopathy, or trigger digit. We analyzed the 1652 patients (37%) who had a return visit at least 3 months later for the same diagnosis. Patients completed the Patient-reported Outcomes Measurement Information System (PROMIS) Depression computerized adaptive test at every office visit (higher scores indicate more depression symptoms) and PROMIS Pain Interference (higher scores indicates greater hindrance in daily life owing to pain). Patients with a return visit were more likely to have surgical treatment and had greater Pain Interference scores at the first visit. Thirteen percent of patients (221 of 1652) had incomplete or missing scores at the initial visit and 33% (550 of 1652) had incomplete or missing scores at the final return visit. We used multiple imputations to account for missing or incomplete data (imputations = 50). In a multivariable linear regression analysis, we compared the mean change in Depression scores between patients treated operatively and those treated nonoperatively, accounting for PROMIS Pain Interference scores at the first visit, age, gender diagnosis, provider, and treatment duration. A post-hoc power analysis demonstrated that the smallest patient cohort (benign lump, n = 176) provided 99% power (α = 0.05) with eight predictor variables to detect a change of 2 points in the PROMIS Depression score (minimally important difference = 3.5). RESULTS: After controlling for potentially confounding variables such as pain interference and age, only carpal tunnel release was associated with a slightly greater decrease in depression symptoms compared with nonoperative treatment (regression coefficient [RC] = -3 [95% confidence interval -6 to -1]; p = 0.006). In patients with the highest PROMIS Depression scores for each diagnosis, operative treatment was not associated with an improvement in depression symptoms (carpal tunnel release: RC = 5 [95% CI -7 to 16]; p = 0.44). Moreover, a corticosteroid injection was not associated with fewer depression symptoms than no biomedical treatment (carpal tunnel release: RC = -3 [95% CI -8 to 3]; p = 0.36). CONCLUSIONS: Given that operative treatment of hand pathology is not generally associated with a decrease in depression symptoms, our results support treating comorbid depression as a separate illness rather than as a secondary effect of pain or physical limitations. LEVEL OF EVIDENCE: Level II, therapeutic study.

Assessment of Pronator Quadratus Repair Integrity Using Dynamic Ultrasonography Following Volar Plate Fixation for Distal Radius Fractures.

Background: Previous work evaluating the pronator quadratus (PQ) muscle following volar plate fixation (VPF) of distal radius fractures (DRF) suggests that PQ repair often fails in the postoperative period. The purpose of this investigation was to assess PQ repair integrity following VPF of DRF using dynamic musculoskeletal ultrasonography. Methods: Twenty adult patients who underwent VPF of DRF with repair of the PQ with a minimum follow-up of 3 months underwent bilateral dynamic wrist ultrasonography. The integrity of the PQ repair, wrist range of motion (ROM) and strength, and functional outcome scores were assessed. Results: Mean patient age at the time of surgery was 59 ± 14 years, and 50% underwent VPF of their dominant wrist. Patients were evaluated at a mean 9 ± 4 months after VPF. All patients had an intact PQ repair. The volar plate was completely covered by the PQ in 55% of patients and was associated with a larger PQ when compared to patients with an incompletely covered volar plate (P = .026). The flexor pollicis longus tendon was in contact with the volar plate in 20% of patients, with those patients demonstrating a trend toward significantly increased wrist flexion (P = .053). No difference in ROM, strength, or outcome scores was noted among wrists with completely or incompletely covered volar plates. Conclusions: The PQ demonstrates substantial durability after repair following VPF. Wrist ROM, strength, and functional outcomes are similar in wrists in which the volar plate is completely or incompletely covered by the repaired PQ.

Early Versus Late Motion Following Volar Plating of Distal Radius Fractures.

Background: Distal radius fractures are common, and the trend in fixation has included the use of locked volar plating. The duration of splinting required after surgery and the effect splinting has upon outcome of the wrist are not clear. Our aim was to compare outcome of patients treated with early versus late motion protocol after volar plating. Methods: Thirty-three patients with distal radius fractures were prospectively and randomly enrolled into an early versus late motion study including volar plating of the distal radius fracture. Early motion included an active and passive wrist motion protocol by 14 days after surgery and delayed motion was initiated at 5 weeks. Fractures were defined as intra-articular and extra-articular, and those with, and without, ulnar styloid fracture. Motion and outcome scores (Disabilities of the Arm, Shoulder and Hand [DASH]/patient-rated wrist evaluation [PRWE]), and strength were measured through 1 year. Results: Wrist motion, DASH, and PRWE scores were only significantly different at 6 weeks with no significant differences at any later time points up to 1 year. One patient had complex regional pain syndrome (CRPS) and one had adhesive capsulitis in the late motion group. Conclusions: Following locked volar plating of distal radius fractures, early motion favored earlier return of motion along with lower DASH, PRWE, and pain scores within first 6 weeks. Although the late motion group had delayed recovery, there were no long-term significant differences in motion, strength, outcome, or pain scores. The 2 cases with complications (CRPS and adhesive capsulitis) did occur in the late motion group and may implicate late motion with these problems.

Nickel-titanium arched shape-memory alloy connector combined with bone grafting in the treatment of scaphoid nonunion.

PURPOSE: To summarize the techniques and clinical effectiveness in treating scaphoid nonunion with nickel-titanium (Ni-Ti) arched shape-memory alloy connector in combination with autologous iliac bone grafts. METHODS: This study retrospectively analyzed 18 scaphoid nonunion cases treated with arched connectors with autologous iliac bone grafts. Based on scaphoid nonunion, 2 cases were classified as type II (fibrous union), 4 cases as type III (mild sclerotic union), 6 cases as type IV (moderate resorption and sclerosis), 5 cases as type V (severe bone resorption and sclerosis), and 1 case as type VI (pseudarthrosis formation). At the first 4, 8 and 12 weeks after the surgery, wrist anteroposterior, lateral X-ray were obtained, respectively, to evaluate bone healing. Patients who had not yet reached the standard of healing at 12 weeks after surgery would continue to receive additional appointments for follow-up visits, such as 14 weeks, 16 weeks, 18 weeks after surgery, until their imaging studies had achieved satisfactory bone healing. Clinical effectiveness was evaluated comprehensively, based on bone union time, Mayo wrist score, and visual analog pain score. RESULTS: All 18 patients achieved satisfactory reduction and fixation with a mean union time of 4.2 months. Preoperative Mayo wrist score averaged 57.4 and average final postoperative follow-up was 91.4. On the other hand, mean preoperative VAS score was 6.8, and final postoperative follow-up average was 1.6. Mayo wrist score of the overall treatment effectiveness was excellent (90-100) in 12 cases, good (80-90) in 5 cases, and acceptable (60-80) in 1 case with zero poor (below 60) cases observed. Statistical analysis suggested that a statistically significant improvement in fracture healing, wrist function recovery and visual analog pain after surgery when compared to the scores of the patients before surgery. CONCLUSION: Using Ni-Ti arched shape-memory alloy connector in combination with autologous bone grafting provided a new modality to treat scaphoid nonunions in a less traumatic, convenient to operate and satisfactory manner in treatment outcomes, and thus is worthy of further application.

Design and development of a pool and billiards assistive device for the physically challenged.

This research entailed the development and prototyping of a bespoke assistive device for a subject who was a local pool and billiards championship player. The subject was diagnosed with a brain tumor and had to undergo surgery followed by chemotherapy to completely remove the mass in the brain. Following this, there was some loss in motor skills on the right side of his body affecting his gait and grip on objects and his ability to play pool and billiards. Concepts were developed to enable the subject to regain some form. A final design was made, with subsequent alterations for fit and comfort. Testing was done over a 7-day period and results using aid were compared without using any aid over a similar period. There was an 88% decrease in time taken to execute the shot, a 140% increase in strength of shot and a 75% increase in accuracy. The results suggest greater improvement in these performance characteristics with extended use of the device. The device also serves to improve the quality of life of the subject. Implications for Rehabilitation A subject lost some physical ability following the removal of a brain tumor. A bespoke design was found to significantly enhance the performance of the subject in pool and billiards, a game that the subject loved to play before loss of the physical ability. Of increasing importance to those that have lost physical ability is the aim to restore quality of life similar to before the loss of the physical ability, especially with respect to activities that a subject would have been motivated to do due to intrinsic love/interest of the activity.

Dorsal and volar wrist ganglions: The results of surgical treatment.

BACKGROUND: The wrist, especially its dorsal surface, is the most common location of ganglion cysts in the human body. OBJECTIVES: The purpose of this study was to present our experience in the treatment of wrist ganglions and to evaluate the results obtained with the operative management of this type of lesion. MATERIAL AND METHODS: A total of 394 patients (289 females and 105 males, aged 10-83 years) treated operatively for wrist ganglions between 2000 and 2014 were included in the study. The results of surgical treatment were evaluated after a minimal 2-year-long follow-up in 69.4% of patients operated on for dorsal wrist ganglions and in 70.6% of patients after the excision of volar wrist ganglions. The shape and size of postoperative scar, range of motion of the wrist, grip strength, severity of pain, and presence/absence of ganglion recurrence were assessed. The influence of demographic factors on the risk of recurrence was statistically analyzed. RESULTS: Persistent limitation of wrist palmar flexion was observed in 6 patients after the removal of dorsal wrist ganglions. There were no cases of postoperative grip strength weakening. An unesthetic scar developed in 15 patients after the excision of dorsal wrist ganglions and in 6 patients after the removal of volar wrist ganglions. Postoperative pain was observed in 7 patients with ganglion recurrence and in 17 patients without recurrence. Ganglion cysts recurred in 12.1% of patients treated for dorsal wrist ganglions and in 10.4% of patients operated on for volar wrist ganglions. No influence of patient gender, age, body side, or cyst location on ganglion recurrence was detected. CONCLUSIONS: Operative treatment is a widely recognized method of management of wrist ganglions. The rate of resulting persistent complications is low. Recurrence of ganglion cysts is unpredictable and independent of patient demographic factors. It can be observed even in cases, in which a perfect surgical technique has been used.

Sonography-guided arthroscopic excision is more effective for treating volar wrist ganglion than dorsal wrist ganglion.

The purpose of this study was to compare the treatment results of sonography-guided arthroscopic excision for volar and dorsal wrist ganglions. A total of 42 patients with wrist ganglions underwent sonography-guided arthroscopic resection. Clinical outcome measures included wrist range of motion, grip strength, patient-rated questionnaire Hand20, and numerical pain rating scale. All patients were assessed for recurrence throughout the follow-up period. Ganglions were located at the dorsal wrist in 26 cases and at the volar wrist in 16 cases. The mean Hand20 and pain scores were significantly improved after sonography-guided arthroscopic resection for both volar and dorsal wrist ganglions. Recurrence was seen in six cases (23%) of dorsal wrist ganglion but no cases of volar wrist ganglion (P < .05). The use of sonography-guided arthroscopic ganglion excision is better for treating volar wrist ganglion than dorsal wrist ganglion.

The Accuracy of Atrial Fibrillation Detection from Wrist Photoplethysmography. A Study on Post-Operative Patients.

Atrial fibrillation (AF) is the most common type of cardiac arrhythmia. Although not life-threatening itself, AF significantly increases the risk of stroke and myocardial infarction. Current tools available for screening and monitoring of AF are inadequate and an unobtrusive alternative, suitable for long-term use, is needed. This paper evaluates an atrial fibrillation detection algorithm based on wrist photoplethysmographic (PPG) signals. 29 patients recovering from surgery in the post-anesthesia care unit were monitored. 15 patients had sinus rhythm (SR, 67.5± 10.7 years old, 7 female) and 14 patients had AF (74.8± 8.3 years old, 8 female) during the recordings. Inter-beat intervals (IBI) were estimated from PPG signals. As IBI estimation is highly sensitive to motion or other types of noise, acceleration signals and PPG waveforms were used to automatically detect and discard unreliable IBI. AF was detected from windows of 20 consecutive IBI with 98.45±6.89% sensitivity and 99.13±1.79% specificity for 76.34±19.54% of the time. For the remaining time, no decision was taken due to the lack of reliable IBI. The results show that wrist PPG is suitable for long term monitoring and AF screening. In addition, this technique provides a more comfortable alternative to ECG devices.

An ergonomic field study to evaluate the effects of a rotatable handle piece on muscular stress and fatigue as well as subjective ratings of usability, wrist posture and precision during laparoscopic surgery: an explorative pilot study.

PURPOSE: The interface between surgeon and the laparoscopic instrument is an important factor in biomechanical stress that may increase the risk of musculoskeletal complaints in surgeons. This article investigates the effect of a laparoscopic instrument with a rotatable handle piece (rot-HP) on muscular stress and fatigue during routine laparoscopic procedures (LP) as well as usability, wrist posture and working precision. METHODS: 40 LP (subtotal hysterectomies) performed by 11 surgeons were investigated. 20 LP were carried out with the rot-HP and 20 with a fixed (standard) laparoscopic handle piece instrument. Shoulder and arm muscle activity was monitored via surface electromyography (sEMG). The electrical activity (EA) and median power frequency (MPF) were used to determine muscular stress and fatigue. Usability, wrist posture, and working precision between handle piece conditions were assessed by a survey. RESULTS: Using the rot-HP did not reduce muscular stress. A tendency of muscular fatigue (increasing EA, decreasing MPF) occurred in the upper trapezius, middle deltoid and extensor digitorum muscles; however, no differences were found between handle pieces. Wrist posture was more comfortable using the rot-HP and working precision and usability tended to be preferred using the standard handle piece. CONCLUSIONS: Although wrist posture seemed to be optimized by the rot-HP, no effect on muscular stress and fatigue was observed in routine LP (< 60 min duration). Optimization of wrist posture may provide positive effects in mid- or long-term procedures. However, sufficient familiarization with the new instrument is crucial since working precision and usability could be impaired.