Objective To design customized titanium alloy lunate prosthesis, construct three-dimensional finite element model of wrist joint before and after replacement by finite element analysis, and observe the biomechanical changes of wrist joint after replacement, providing biomechanical basis for clinical application of prosthesis. Methods One fresh frozen human forearm was collected, and the maximum range of motions in flexion, extension, ulnar deviation, and radialis deviation tested by cortex motion capture system were 48.42°, 38.04°, 35.68°, and 26.41°, respectively. The wrist joint data was obtained by CT scan and imported into Mimics21.0 software and Magics21.0 software to construct a wrist joint three-dimensional model and design customized titanium alloy lunate prosthesis. Then Geomagic Studio 2017 software and Solidworks 2017 software were used to construct the three-dimensional finite element models of a normal wrist joint (normal model) and a wrist joint with lunate prosthesis after replacement (replacement model). The stress distribution and deformation of the wrist joint before and after replacement were analyzed for flexion at and 15°, 30°, 48.42°, extension at 15°, 30°, and 38.04°, ulnar deviation at 10°, 20°, and 35.68°, and radial deviation at 5°, 15°, and 26.41° by the ANSYS 17.0 finite element analysis software. And the stress distribution of lunate bone and lunate prosthesis were also observed. Results The three-dimensional finite element models of wrist joint before and after replacement were successfully constructed. At different range of motion of flexion, extension, ulnar deviation, and radial deviation, there were some differences in the number of nodes and units in the grid models. In the four directions of flexion, extension, ulnar deviation, and radial deviation, the maximum deformation of wrist joint in normal model and replacement model occurred in the radial side, and the values increased gradually with the increase of the range of motion. The maximum stress of the wrist joint increased gradually with the increase of the range of motion, and at maximum range of motion, the stress was concentrated on the proximal radius, showing an overall trend of moving from the radial wrist to the proximal radius. The maximum stress of normal lunate bone increased gradually with the increase of range of motion in different directions, and the stress position also changed. The maximum stress of lunate prosthesis was concentrated on the ulnar side of the prosthesis, which increased gradually with the increase of the range of motion in flexion, and decreased gradually with the increase of the range of motion in extension, ulnar deviation, and radialis deviation. The stress on prosthesis increased significantly when compared with that on normal lunate bone. Conclusion The customized titanium alloy lunate prosthesis does not change the wrist joint load transfer mode, which provided data support for the clinical application of the prosthesis.
ObjectiveTo evaluate the effectiveness of nitinol memory alloy two foot fixator combined with Kirschner wire in the treatment of trans-scaphoid perilunate dislocation.MethodsBetween September 2011 and October 2018, 17 patients with trans-scaphoid perilunate dislocation were treated with nitinol memory alloy two foot fixator and Kirschner wire. There were 12 males and 5 females, with an average age of 32.6 years (range, 23-52 years). The disease duration was 8 hours to 9 days, with an average of 6.5 days. The causes of injury included 6 cases of falling injury, 4 cases of traffic accident injury, 3 cases of stress injury of wrist caused by sports, 2 cases of violent injury of wrist caused by machine impact, 1 case of military training injury, and 1 case of other injury. One case was complicated with nerve injury. According to Herbert’s classification, all the fractures were type B4. At 1 week before operation, 3 months, 6 months after operation and last follow-up, the wrist function was evaluated according to the Krimmer scale score.ResultsAll the 17 patients were followed up 10.5-48 months, with an average of 18.6 months. There was no loosening or infection of the internal fixator, no necrosis of the scaphoid and lunate. The periosteal dislocations of the patients were well reduced and the scaphoid fractures all healed. The healing time was 4-18 months, with an average of 11.3 months. The Krimmer wrist scores were 37.5±4.4, 61.3±7.2, 83.3±9.3, 87.3±8.2 at 1 week before operation, 3 months, 6 months after operation and last follow-up, respectively. The Krimmer wrist score at each time point after operation was significantly improved when compared with that before operation (P<0.05), and at 6 months after operation and last follow-up than at 3 months after operation (P<0.05). There was no significant difference between at 6 months and last follow-up (P>0.05). At last follow-up, the Krimmer wrist function was excellent in 13 cases, good in 2 cases, fair in 1 case, poor in 1 case, and the excellent and good rate was 88.23%.ConclusionNitinol memory alloy two foot fixator combined with Kirschner wire in the treatment of trans-scaphoid periosteal dislocation has definite effectiveness, simple operation, and good recovery of wrist function after operation.
OBJECTIVE There are various methods used to treat the Kienbock’s disease with various outcomes. This study investigated the effect of combining acrylic lunate prosthesis replacement with resection of articular branches to wrist from anterior and dorsal interosseous nerve. METHODS From January 1992 to January 1997, six cases were included. All of the patients were in stage III according to Lichtman’s classification. Besides replacement of the acrylic lunate prosthesis, segment of the pure sensory branches from anterior and posterior interosseous nerves were resected. RESULTS Follow-up for 10 to 54 months (an average of 32 months) the pain was relieved in all patients except one. The range of movement of wrists were as followings: The extension of the wrist was 20 to 35 degrees (an average of 26 degrees) and flexion was 20 to 35 degrees (an average of 32 degrees). There was no improvement in radial and ulnar deviation. CONCLUSION Lunate prosthesis replacement combined with resection of articular branches to wrist resulted in a painless wrist and was a satisfactory method.
Objective To find out some parameters to judge the stability of the wrists after four-corner arthrodesis and to explore the strategyfor improving the range of motion (ROM) of the wrist after four-corner arthrodesis. Methods After the simulated four-corner arthrodesis was performed in both wrists of 8 men and 4 women cadaver, the wrists were fixed on the wrist motor simulator; and wrist movement including flexion, extension, radial deviation, ulnar deviation was simulated. The standard posteroanterior and lateral radiographs were taken for measuring the change of capitolunate angle（α）, radiolunate angle（β）, capitolunate posteroanterior angle（θ）, the height（H）and width（W）of the fused four carpal bone bloc. Results There were statistically significant differences in α,β,θ angles (P＜0.01) in the case of 50° flexion or 40° extension, and in H and W values (P＜0.05) in the case of 25° ulnar deviation or 15° radial deviation when compared with before movement. Conclusion Capitolunate angle, radiolunate angle, capitolunate posteroanterior angle, the height and the width of thefused four carpal bone bloc can be used to judge the stability of the wrists after four-corner arthrodesis.
Objective To study and compare boneforming mechanismafter compound of autologous periosteum-wrapped tendon with spongiosa homogenate and other implants in articular cavity, and to explore the possibility of the compound as a substitute for the lunate in Kienbock’s disease.Methods Forty-five New Zealand white rabbits were randomly divided into three groups: periosteum group(group A, n=15), composite group(group B, n=15), and control group(group C, n=15). The three sorts of implants were placed into articular cavity of the knee respectively. The changes of bone formation and bone morphogenetic protein (BMP) distribution of the implants were examined under optical microscope with HE and immunohistochemical staining and measured by CT 3, 6 and 9 weeks after operation.Results The result of BMP staining was negative after 3 weeks and positive in new cartilage cells after 9 weeks in group A. The positive BMP staining was observed in group B after 3 weeks and 9 weeks, which mainly distributed in new bone cells and cartilage cells. And negative BMP staining was observed every stage in groupC. The quantitative CT bone mineral density (BMD) values of 3 implants were analyzed, the difference was significant between the groups (Plt;0.01), except that between groups A and C in the 3rd week (Pgt;0.05). Conclusion The above results demonstrated that the compound of autologous periosteum-wrapped tendon and spongiosa homogenate can produce bone and cartilage massively under the induction of periosteum and bone-forming factors such as BMP in spongiosa homogenate and the compound can be used as a substitute for the lunate.
目的:介紹以骨間前動脈背側支為蒂的頭狀骨移位治療晚期月骨無菌性壞死。方法:對7例Lichtman分Ⅲ、Ⅳ期月骨無菌性壞死患者采用壞死月骨摘除,以骨間前動脈背側支為蒂的頭狀骨移位替代壞死月骨。結果:術后隨訪1～5年,平均32個月,移位頭狀骨有可靠血運,6例腕痛消失,1例仍有輕度腕痛,優良率100%。結論:應用該法替代月骨支撐腕關節,符合腕關節功能解剖,是治療Ⅲ、Ⅳ期月骨無菌性壞死的有效方法。
ObjectiveTo investigate the effectiveness of Kirschner wire fixation in scapholunate joint, capitolunate joint, and lunotriquetral joint combined with bone anchor repair for the treatment of acute perilunate injury. MethodsBetween January 2007 and January 2012, 35 cases of acute perilunate injury were treated. There were 30 males and 5 females with an average age of 45.5 years (range, 32-56 years). Fractures were caused by falling from height in 18 cases, by traffic accident in 11 cases, and by fall injury in 4 cases. The time from injury to operation was 2-6 days (mean, 3.4 days). There were 23 cases of trans-scaphoid perilunate dislocation, 10 cases of perilunate dislocation, and 2 cases of trans-triangular perilunate dislocation. Associated injuries included median nerve injury in 6 cases, radius styloid fracture in 8 cases, ulnar styloid fracture in 2 cases, and distal tibial fracture in 1 case. All the patients were treated by open reduction, Herbert screw fixation of scaphoid fractures, and Kirschner wire fixation in scapholunate joint, capitolunate joint, and lunotriquetral joint, and the intercarpal ligaments were repaired by Mitek bone anchor. ResultsSuperficial wound infection occurred in 2 cases, and primary healing of incision obtained in others. Thirty-five patients were followed up 12-35 months (mean, 18 months). X-ray films showed fracture union in 21 cases of scaphoid fractures, and bone nonunion in 2 cases of scaphoid fractures. During the follow-up period, there was no avascular necrosis of scaphoid or lunate. At last follow-up, the scapholunate angle, radiolunate angle, and wrist range of motion (ROM) in extension had no significant difference between affected and unaffected sides (P > 0.05). The wrist ROM in flexion and grip strength of affected side were not up to the levels of unaffected side (P < 0.05). According to the modified Mayo wrist scoring system, the score was 79.9±10.7, which were excellent in 8 cases, good in 17 cases, fair in 7 cases, and poor in 3 cases, and the excellent and good rate was 71.4%. The disability of arm-shoulder-hand (DASH) questionnaires score was 21±10. Traumatic osteoarthritis was observed in 2 cases. ConclusionKirschner wire fixation in scapholunate joint, capitolunate joint, and lunotriquetral joint combined with bone anchor repair for the treatment of acute perilunate injury can get early stability of the carpal joint, favorable intercarpal ligament repair, and good recovery of wrist joint function.
ObjectiveTo provide anatomical basis for vascularized pisiform transfer in the treatment of advanced avascular necrosis of the lunate (Kienb?ck’s disease) by studying its morphology and blood supply pattern based on digital technique.MethodsTwelve adult fresh wrist joint specimens were selected and treated with gelatin-lead oxide solution from ulnar or radial artery. Then the three-dimensional (3D) images of the pisiform and lunate were reconstructed by micro-CT scanning and Mimics software. The morphologies of pisiform and lunate were observed and the longitudinal diameter, transverse diameter, and thickness of pisiform and lunate were measured. The main blood supply sources of pisiform were observed. The number, diameter, and distribution of nutrient foramina at proximal, distal, radial, and ulnar sides of pisiform were recorded. The anatomic parameters of the pedicles (branch of trunk of ulnar artery, carpal epithelial branch, descending branch of carpal epithelial branch, recurrent branch of deep palmar branch) were measured, including the outer diameter of pedicle initiation, distance of pedicle from pisiform, and distance of pedicle from lunate. ResultsThere were significant differences in the longitudinal and transverse diameters between pisiform and lunate (t=6.653, P=0.000; t=6.265, P=0.000), but there was no significant difference in thickness (t= 1.269, P=0.109). The distal, proximal, radial, and ulnar sides of pisiform had nutrient vessels. The nutrient foramina at proximal side were significantly more than that at distal side (P<0.05), but there was no significant difference in the diameter of nutrient foramina between different sides (P>0.05). The outer diameter of pedicle initiation of the recurrent branch of deep palmar branch was significantly smaller than the carpal epithelial branch and descending branch of carpal epithelial branch (P<0.05). There was no significant difference in the distance of pedicle from pisiform/lunate between branch of trunk of ulnar artery and recurrent branch of deep palmar branch (P>0.05), and between carpal epithelial branch and descending branch of carpal epithelial branch (P>0.05). But the differences between the other vascular pedicles were significant (P<0.05). ConclusionThere are abundant nutrient vessels at the proximal and ulnar sides of pisiform, so excessive stripping of the proximal and ulnar soft tissues should be avoided during the vascularized pisiform transfer. It is feasible to treat advanced Kienb?ck’s disease by pisiform transfer with the carpal epithelial branch of ulnar artery and the descending branch.
The purpose of this study was to investigate the arterial supply of the pisiform bone. Fifty upper extremities from adult human cadavers of both sexes were studied. The observations showed that there was a small branch(named the main artery of pisiform) arising from the lower part of the ulnar artery in each cases. The mean value of the length of the main artery of the pisiform was 23.89±8.68mm, the diameter of the artery was 0.79±0.21mm. The length, width and thickness of the pisiform were 11. 61±1.98mm, 11.40±1.87mm and 10.30±1.26mm, respectively. The length and width of the space accupied by the lunate on the X-ray films were measured, they were 16.38±1.96mm and 12.03±1.17mm, respectively.
Objective To investigate the long-term effectiveness of Ni-Ti memory alloy tripod fixator in the treatment of Kienb?ck disease. Methods The clinical data of 22 patients with Kienb?ck disease who were treated with Ni-Ti memory alloy tripod fixator between January 2011 and September 2013 and followed up more than 10 years was retrospectively analyzed. There were 14 males and 8 females with an average age of 45 years (range, 20-64 years). The Lichtman staging was stage Ⅲb. According to AO/Association for the Study of Internal Fixation (AO/ASIF) classification, there were 6 cases of type B1, 2 cases of type B2, 10 cases of type B3, and 4 cases of type C2. The disease duration ranged from 18 to 50 months, with an average of 30.7 months. The operation time, intraoperative blood loss, and complications were recorded. Wrist height ratio and scapholunate angle were measured by wrist anteroposterior and lateral X-ray films before and after operation. The grip strength of bilateral hands was measured by Jamar dynamometer. The wrist pain was evaluated by visual analogue scale (VAS) score, and the wrist function was evaluated by Mayo score, and the radial deviation, ulnar deviation, dorsiflexion, and palmar flexion range of motion of wrist were measured. Results The operation time was 45-60 minutes, with an average of 52.21 minutes; the intraoperative blood loss was 50-60 mL, with an average of 58.63 mL. No nerve or blood vessel injury occurred during operation. All patients were followed up 10-13 years (mean, 11.3 years). X-ray films at 3 months after operation showed that the density of lunate bone was lower than that before operation. Satisfactory fusion of the scapho-trapezio-trapezoeid joint was achieved at 3-6 months after operation (mean, 4.5 months), and the wrist height ratio and the scapholunate angle after fusion significantly improved when compared with those before operation (P<0.05). Wrist pain relieved, scaphoid rotation and dislocation improved, and no radiocarpal joint degeneration was found during follow-up, and no internal fixator loosening, breakage, or lunate bone necrosis occurred. At last follow-up, the wrist radial deviation, ulnar deviation, dorsiflexion, and palmar flexion range of motion, VAS score, and grip strength of the affected side significantly improved when compared with those before operation (P<0.05); the grip strength of the affected side recovered to 99.00%±1.25% of the healthy side. Mayo score ranged from 72 to 93, with an average of 85; 14 cases were rated as excellent, 5 good, and 3 satisfactory, the excellent and good rate was 86.4%. ConclusionIn the treatment of stage Ⅲb Kienb?ck’s disease, the scapho-trapezio-trapezoeid joint usion using Ni-Ti memory alloy tripod fixator can effectively reduce pain, improve hand function, and prevent further deterioration, and achieve good long-term effectiveness.