Thumb Fingertips Research Articles

V-Y Flap Over Moberg's Flap to Cover the Thumb's Fingertip Injury: Technique and Cases.

The Moberg flap has been used to achieve coverage of amputations of the thumb's fingertip. However, it has been associated with flexion contractures of the interphalangeal (IP) joint of the thumb. A modification of the surgical technique is presented, adding a distal V-Y flap to allow greater advancement, and avoiding IP joint contractures. The proposed surgical technique is presented, and a case series of patients treated with this modification is introduced. A total of 5 patients underwent this surgical technique. All the flaps healed without complications. No patient presented stiffness or flexion contracture of the thumb´s IP joint. There were no cases of neuropathic pain and the 2-point discrimination over the flap was 6.8mm on average. In conclusion, the proposed variation to the Moberg's flap allows adequate coverage of injuries to the thumb's fingertip with a low rate of complications, adequate sensitivity of the reconstructed digit and avoiding flexion contractures of the IP joint.

Simulative Evaluation of a Joint-Cartesian Hybrid Motion Mapping for Robot Hands Based on Spatial In-Hand Information.

Two sub-problems are typically identified for the replication of human finger motions on artificial hands: the measurement of the motions on the human side and the mapping method of human hand movements (primary hand) on the robotic hand (target hand). In this study, we focus on the second sub-problem. During human to robot hand mapping, ensuring natural motions and predictability for the operator is a difficult task, since it requires the preservation of the Cartesian position of the fingertips and the finger shapes given by the joint values. Several approaches have been presented to deal with this problem, which is still unresolved in general. In this work, we exploit the spatial information available in-hand, in particular, related to the thumb-finger relative position, for combining joint and Cartesian mappings. In this way, it is possible to perform a large range of both volar grasps (where the preservation of finger shapes is more important) and precision grips (where the preservation of fingertip positions is more important) during primary-to-target hand mappings, even if kinematic dissimilarities are present. We therefore report on two specific realizations of this approach: a distance-based hybrid mapping, in which the transition between joint and Cartesian mapping is driven by the approaching of the fingers to the current thumb fingertip position, and a workspace-based hybrid mapping, in which the joint–Cartesian transition is defined on the areas of the workspace in which thumb and fingertips can get in contact. The general mapping approach is presented, and the two realizations are tested. In order to report the results of an evaluation of the proposed mappings for multiple robotic hand kinematic structures (both industrial grippers and anthropomorphic hands, with a variable number of fingers), a simulative evaluation was performed.

Thumb fingertip injuries reconstruction using a dorsoulnar flap of the thumb combined with relay V-Y flaps for donor site repair.

To assess the clinical value and feasibility of the dorsoulnar flap of the thumb combined with relay V-Y flaps for reconstruction of the thumb fingertip injuries. In this retrospective study, we retrospectively reviewed 20 patients (13 men, 7 women; June 2014-June 2016) with thumb fingertip defects who underwent reconstructive procedures with transfer of the dorsoulnar flap of the thumb. The average size of the defects ranged from 1.8 cm × 2.0 cm to 2.0 cm × 3.0 cm, whereas the reconstructed dorsoulnar flap of the thumb ranged in size from 2.0 cm × 2.2 cm to 2.2 cm × 3.0 cm. A V-Y flap was used to repair the donor site at the same time. Sensation within the reconstructed thumb, the aesthetic appearance of both the donor and recipient sites, functional recovery, and return-to-work (RTW) time were measured. All 40 flaps survived without necrosis. The follow-up period ranged from 6 to 24 months. There were no complications reported. The mean static two-point discrimination values at the reconstructed thumb fingertip and donor site were 8.5 mm (range 8-10 mm) and 12.5 mm (range 12-14 mm), respectively. The average visual analog scores for the aesthetic appearance of the recipient and donor sites were 8.4 (range 8-9.5) and 9.6 (range 9-10), respectively. The average Michigan Hand Outcome Questionnaire score for the reconstructed hand was 9.4 (range 6-16). The average RTW time was 9.8 weeks (range 6-13 weeks). All patients were satisfied with the aesthetic outcome. The dorsoulnar flap of the thumb is an ideal alternative for reconstruction of the thumb fingertip injuries, and a V-Y flap was suitable for repairing the donor site with a reduced incidence of complications.

Fine adaptive precision grip control without maximum pinch strength changes after upper limb neurodynamic mobilization

Before and immediately after passive upper limb neurodynamic mobilizations targeting the median nerve, grip (G_F) and load (L_F) forces applied by the thumb, index and major fingers (three-jaw chuck pinch) were collected using a manipulandum during three different grip precision tasks: grip-lift-hold-replace (GLHR), vertical oscillations (OSC), and vertical oscillations with up and down collisions (OSC/COLL/u, OSC/COLL/d). Several parameters were collected or computed from G_F and L_F. Maximum pinch strength and fingertips pressure sensation threshold were also examined. After the mobilizations, L_F max changes from 3.2 ± 0.4 to 3.4 ± 0.4 N (p = 0.014), dG_F from 89.0 ± 66.6 to 102.2 ± 59.6 N~text{s}^{-1} (p = 0.009), and dL_F from 43.6 ± 17.0 to 56.0 ± 17.9 N~text{s}^{-1} (p<0.001) during GLHR. L_F SD changes from 0.9 ± 0.3 to 1.0 ± 0.2 N (p = 0.004) during OSC. L_F peak changes from 17.4 ± 8.3 to 15.1 ± 7.5 N (p<0.001), G_F from 12.4 ± 6.7 to 11.3 ± 6.8 N (p = 0.033), and L_F from 2.9 ± 0.4 to 3.00 ± 0.4 N (p = 0.018) during OSC/COLL/u. G_F peak changes from 13.5 ± 7.4 to 12.3 ± 7.7 N (p = 0.030) and L_F from 14.5 ± 6.0 to 13.6 ± 5.5 N (p = 0.018) during OSC/COLL/d. Sensation thresholds at index and thumb were reduced (p = 0.001, p = 0.008). Precision grip adaptations observed after the mobilizations could be partly explained by changes in cutaneous median-nerve pressure afferents from the thumb and index fingertips.

Bundling method to treat extensive thumb fingertip pulp incisions: A case report

Introduction. Thumb fingertip injuries, often combined with phalanx fracture or torn ligament, are very common. The focus of treatment is on how to rebuild the function and shape of the thumb. Single thumb fingertip pulp injury is more common. However, due to the diverse type of injury, no uniform treatment guideline is described in the literature. Case report. A patient with extensive thumb fingertip pulp incisions, which looked like multiple parallel wounds, was admitted to our Emergency Department. We used the method of bundling to maintain the shape of the fingertip. A single suture to pass through all the incisions was performed and then the suture was tied outside the skin. After that, we bandaged them with sterile bandages. Finally, good contour and fingertip function were restored. Conclusion. We successfully used the bundling method to treat patient with extensive thumb fingertip pulp incisions.

Combined Joint-Cartesian Mapping for Simultaneous Shape and Precision Teleoperation of Anthropomorphic Robotic Hands

Abstract There are many applications involving robotic hands in which teleoperation-based approaches are preferred to autonomous solutions. The main reason is that cognitive skills of human operators are desirable in some task scenarios, in order to overcome limitations of robotic hands abilities in dealing with unstructured environments and/or unpredetermined requirements. In particular, in this work we focus on the use of anthropomorphic grasping devices and, specifically, on their teleoperation based on movements of the human operator’s hand (the master hand.) Indeed, the mapping of human hand configurations to an anthropomorphic robotic hand (the slave device) is still an open problem, because of the presence of dissimilar kinematics between master and slave that produce shape and/or Cartesian errors – as addressed within our study. In this work, we propose a novel algorithm that combines joint and Cartesian mappings in order to enhance the preservation of both finger shapes and fingertip positions during the teleoperation of the robotic hand. In particular, a transition between the joint and Cartesian mappings is realized on the basis of the distance between the fingertip of the master hands’ thumb and the opposite fingers, in which the mapping of the thumb fingertip is specifically addressed. The result of the testing of the algorithm with a ROS-based simulator of a commercially available robotic hand is reported, showing the effectiveness of the proposed mapping.

Learning to Grasp Familiar Objects Based on Experience and Objects’ Shape Affordance

Stably grasping objects for a specific task is a hot research topic in robotics due to multiple degrees of freedom of hand kinematics, various shapes of objects, and incomplete visual sensing of objects (partial point clouds). This paper proposes an effective grasp planning method by integrating the crucial grasp cues (positions and orientations of thumb fingertips and the wrist) from humans’ grasp experience. This approach has multiple advantages: greatly reducing the search space of the hand kinematics; no reconstruction or registration; being able to directly perform on the partial point cloud of objects. Meanwhile, for various shapes of objects which are partially observable in the single-view visual sensing, the presented approach learns the “thumb” grasp point employing a signature of histograms of orientations shape descriptor based on objects’ category level. This method recognizes the grasp point according to the shape affordance at each point on the object, which performs the grasp point generalization on the familiar objects. Finally, we verify the developed methods via both simulations and experiments by grasping various shapes of objects.

The SSSA-MyHand: A Dexterous Lightweight Myoelectric Hand Prosthesis.

The replacement of a missing hand by a prosthesis is one of the most fascinating challenges in rehabilitation engineering. State of art prostheses are curtailed by the physical features of the hand, like poor functionality and excessive weight. Here we present a new multi-grasp hand aimed at overcoming such limitations. The SSSA-MyHand builds around a novel transmission mechanism that implements a semi-independent actuation of the abduction/adduction of the thumb and of the flexion/extension of the index, by means of a single actuator. Thus, with only three electric motors the hand is capable to perform most of the grasps and gestures useful in activities of daily living, akin commercial prostheses with up to six actuators, albeit it is as lightweight as conventional 1-Degrees of Freedom prostheses. The hand integrates position and force sensors and an embedded controller that implements automatic grasps and allows inter-operability with different human-machine interfaces. We present the requirements, the design rationale of the first prototype and the evaluation of its performance. The weight (478 g), force (31 N maximum force at the thumb fingertip) and speed of the hand (closing time: <370 ms), make this new design an interesting alternative to clinically available multi-grasp prostheses.

The rules of tool incorporation: Tool morpho-functional & sensori-motor constraints

Previous studies showed that using tools modifies the agent’s body and space representation. However, it is still not clear which rules govern those remapping processes. Here, we studied the differential role played by the morpho-functional characteristics of a tool and the sensori-motor constraints that a tool imposes on the hand.To do so, we asked a group of participants to reach and grasp an object using, in different conditions, two different tools: Pliers, to be acted upon by the index and thumb fingertips, and Sticks, taped to the same two digits. The two tools were equivalent in terms of morpho-functional characteristics, providing index finger and thumb with the same amount of elongation. Crucially, however, they imposed different sensori-motor constraints on the acting fingers. We measured and compared the kinematic profile of free-hand movements performed before and after the use of both devices. As predicted on the basis of their equivalent morpho-functional characteristics, both tools induced similar changes in the fingers (but not the arm) kinematics compatible with the hand being represented as bigger. Furthermore, the different sensori-motor constraints imposed by Pliers and Sticks over the hand, induced differential updates of the hand representation. In particular, the Sticks selectively affected the kinematics of the two fingers they were taped on, whereas Pliers had a more global effect, affecting the kinematics of hand movements not performed during the use of the tool. These results suggest that tool-use induces a rapid update of the hand representation in the brain, not only on the basis of the morpho-functional characteristics of the tool, but also depending on the specific sensori-motor constraints imposed by the tool.

Association Between Arterial Stiffness And The Shoulder Flexibility.

The flexibility is one of the important components of the health related physical fitness along with muscular strength, muscular endurance and cardiorespiratory fitness. The shoulder reach flexibility test is simple and easy. On the other hand, it is reported that a less flexible body would have arterial stiffening. Furthermore, there are reports that the arterial stiffness was improved by the six weeks whole body stretch exercises. Therefore we thought whether screening of the arterial stiffening was possible by the shoulder flexibility test. PURPOSE: To investigate whether the shoulder flexibility test is related to an arterial stiffness. METHODS: This study included 344 patients (back pain or knee pain) from 50 to 95 years of age (71.7±9.0ys). The shoulder flexibility was measured by the modified shoulder reach flexibility test (measured the distance between the thumb finger tips; TTD [cm]). Arterial stiffness was determined by brachial-ankle pulse wave velocity (baPWV) and ankle-brachial index (ABI) was measured. The relationship between shoulder flexibility and arterial stiffness were analyzed using linear regression analysis and 3-factor (arterial stiffness, sex, age) ANOVA. RESULTS: The baPWV (regression coefficient =0.203, p<0.01) was significantly associated with TTD. Patients were classified into 3 age groups (50-64ys; n=69, 65-79ys; n=194, 80-95ys; n=81), and normal group [N] (n=86) and arteriosclerosis (included angiostenosis) group [A] (n=219) by an examination of ABI and baPWV. TTD of A groups (male 26.0±10.1; n=50, female 17.8±9.8; n=169) were significant longer than N groups (male 21.9±6.9; n=36, female 14.5±7.3; n=89) (p<.05). TTD of male 65-79ys (N 22.5±6.8; n=21, A 27.7±8.3; n=26) and 80-95ys (N 27.1±4.0; n=4, A 27.8±14.8; n=11) male age groups were significant longer than 50-64ys age groups (N 18.9±6.6; n=11, A 21.2±5.8; n=13) (p<.05). TTD of female 80-95ys age groups (N 17.8±8.7; n=16, A 24.2±11.3; n=50) were significant longer than 50-64ys (N 13.9±7.1; n=20, A 14.9±7.4; n=25) and 65-79ys (N 13.8±6.5; n=53, A 15.1±7.9; n=94) female age groups (p<.05). CONCLUSIONS: In the middle-aged adults and elderly, the value of the modified shoulder reach flexibility test of the groups with suspicion of arteriosclerosis or angiostenosis was longer; in other words, flexibility decreased. The shoulder flexibility test is related to the arterial stiffening and may be available as a screening test.

Thumb fingertip reconstruction with palmar V-Y flaps combined with bone and nail bed grafts following amputation.

The aim of treating thumb fingertip amputations with no indication for replantation is to reestablish functional and esthetic properties. From March 2005 to October 2008, we treated 14 patients with thumb fingertip amputation using palmar V-Y flaps combined with bone and nail bed grafts. There were 10 men and 4 women, whose ages at surgery ranged from 19 to 63 years (mean 35.8 years). In all, 11 of the injuries occurred in the dominant hand. According to Allen's classification, two were type II, seven were type III, and five were type IV. All patients underwent emergency surgery, with a time delay after injury of 3-12 h (mean 6.4 h). In each case, the amputation was a crush or avulsion injury, making microsurgical replantation not feasible. All of the flaps survived. At 8-17 months (average 12.8 months) of follow-up, the average subjective satisfaction score was 8.64. All patients experienced cold intolerance, and none of the patients complained of dysesthesia. Favorable results (excellent or good) were found in 78.6%. Thin primary nails appeared on the grafted nail bed about 3 weeks after surgery, following which the newly formed nail thickened and developed a more natural appearance. In one case, the new nail plate showed abnormal thickening due to hyperkeratosis. The bone graft healed at 5 weeks. The mean two-point discrimination was 7.5 mm. Grip strength was 10% less than that in the unaffected hand. Metacarpophalangeal and proximal interphalangeal joint mobility losses were less than 10°. All patients returned to their jobs. No patients had postoperative complications. We believe that the combination of palmar V-Y flap and bone and nail bed grafts provides a distinct advantage over other choices. It improves function when replantation is not an option.

Transfer of a radial digital artery reverse island flap from proximal phalange of the middle finger to cover fingertip defect of the thumb

Objective To present the application of a radial digital artery reverse island flap from proximal phalange of the middle finger for repair of fingertip defect of the thumb.Methods Ten cases of fingertip defect of the thumb were treated with this flap that was based on radial digital artery at the proximal phalangeal level of the middle finger.The pedicled flap was transferred to the defect site.The donor site was directly closed.To restore sen.~tion of the flap,the dorsal branch of the proper digital nerve was inclnded in the flap and sutured to the proper digital nerve in the severed thumb stump.Results All the flaps survived completely.Incisions were healed by first intention.The patients were follow-up for 3 to 12 months.The thumbs had good appearance after the reconstruction.The flaps were supple and resistant to wear and tear.There was no touch pain.The two-point discrimination was 4 to 6 mm.There was no complication at the donor site and no limitation in the movement of the interphalangeal joint.According to the functional evaluation criteria of the upper limb issued by the Hand Surgery Society of the Chinese Medical Association,active range of motion was rated as excellent in 9 cases and good in 1 case.Conclusion Transfer of the radial digital artery reverse island flap from proximal phalange of the middle finger to cover defects of the thumb tip can lead to good appearance and sensation.It is a simple and reliable operative method. Key words: Island flaps; Surgical procedures, operative; Cross-finger flaps; Thumb fingertip defect

Restoration of active palmar abduction of the thumb in tetraplegia by tendon transfer of the extensor digiti minimi to abductor pollicis brevis

We describe a method to restore active palmar abduction of the thumb and report its functional impact in tetraplegia. At 54.2 (SD 42.8) months after cervical spinal cord injury (12 traumatic, 3 nontraumatic), the extensor digiti minimi (EDM) tendon was transferred to the abductor pollicis brevis (APB) through the interosseous membrane in 15 tetraplegic patients (age range 19-70 years) in addition to a mean 3.2 procedures to restore key pinch. According to International Classification, the operated upper extremities were in the OCu4 to OCu8 (1 patient X) group. The maximum distance between thumb and index finger tips during active or passive opening of the hand, maximum angle of palmar abduction, grip and key pinch strength, and active finger range of motion were measured. All patients were re-examined after 38.4 (SD 22.7) months. The active thumb-index opening increased significantly from 2.5 (SEM 1.0) cm before to 9.0 (SEM 0.8) cm after surgery. Nine patients without previous active opening of the first web space recovered a mean thumb-index opening of 9.1 (SEM 1.7) cm, whereas this distance increased by an average of 2.9 (SEM 0.8) cm in six patients who had active thumb index distance of 6.3 (SEM 1.6) cm before surgery. All but one patient were able to direct and coordinate key pinch and perform tasks using the restored APB function, including five patients whose EDM strength was rated as grade 3 before transfer. This EDM-to-APB transfer meets the theoretical requirements of architecture matching between donor and recipient muscles, the principles of tendon transfer, and our surgical expectations. We strongly recommend that an active EDM is transferred to the APB to restore opening of the hand and help in key pinch control in patients with tetraplegia.

Clinical application of double V-Y advancement flap to repair thumb fingertip defect

Objective To introduce the clinical application and treatment outcomes of using double V-Y advancement flap for thumb fingertip defects.Methods Nine cases of thumb fingertip defect were treated with double V-Y advancement flap.The smaller V-Y advancement flap was carefully sutured to the nail bed.The bigger V-Y advancement flap was transferred by suturing the ulnar neurovascular bundle to cover the defect.The flaps were 14 mm × 25 mm to 15 mm × 35 mm in size.Donor sites were directly closed. Results Flaps survived completely in all 9 cases,while incisions were healed by first intention.The patients were follow-up for 4 to 12 months.The appearances and function of fingertips were good.The texture of the flap was soft,close to that of the neighboring tissue.The thumbs did not look bulky.Distal thumb pulp was restored.Movement of the interphalangeal joint was normal.There was no hook nail deformity.The two-point discrimination was 5 to 6 mm.According to the functional evaluation criteria of the upper limb issued by the Hand Surgery Society of Chinese Medical Association,active range of motion was rated as excellent in 7 cases and good in 2 cases.Conclusion Double V-Y advancement flap is an ideal method for treatment of thumb fingertip defects. Key words: Surgical flaps; Finger injuries; Thumb

Radial Sensory Neurotization of the Thumb and Index Finger for Prehension After Proximal Median and Ulnar Nerve Injuries

Proximal median nerve injuries are functionally disabling, secondary to both motor and sensory deficits. Reestablishment of sensation relies on slow axonal regeneration originating from the site of injury after either primary nerve repair or the use of autogenous nerve grafts. This regeneration can take 2 or more years to restore sensation to the hand, depending on injury location. Distal sensory nerve transfers shorten the recovery time by decreasing the required regeneration distance. The authors present two case reports of patients with proximal median nerve injury, who underwent radial sensory nerve transfers to the ulnar digital nerve of the thumb and the radial digital nerve of the index finger. Protective sensation returned to the index and thumb fingertips at 3 months. By 6 months, both patients attained sufficient sensation to permit active lateral key pinch. At 9 months, each patient had moving sensation; and by 14 months, each patient attained proper localization. Successful digital nerve transfers of the dorsal radial sensory nerves in patients with high proximal median nerve injuries return sensation faster than traditional median nerve repairs. Use of this technique will significantly reduce the insensate time in patients with this unfortunate injury.

巨大な脂腺癌の１例

We reported a 75-year-old male patient, who had a large tumor mass, about 5×7×4cm, on the left lower eyelid. Histopatholgically, this was sebaceous carcinoma (SC) . Physical examination could not revealed regional lymph nodes swelling. He had advanced hepatocellular carcinoma (HCC) and liver cirrhosis. Wide excision and exenteration and Thiersch's skin graft was performed. He died of HCC. Autopsy was performed. There was no evidence of metastasis of SC to the regional lymph nodes and distant sites.Sebaceous carcinoma is a rare malignant tumor. It is subdivided into periocular and extraocular type. In periocular type, its size is usually at most thumb finger tip size, larger one is very rare. Our case may be the largest one.