ObjectiveTo determine the entry point and screw implant technique in posterior pedicle screw fixation by anatomical measurement of adult dry samples of the axis so as to provide a accurate anatomic foundation for clinical application. MethodsA total of 60 dry adult axis specimens were selected for pedicle screws fixation. The entry point was 1-2 mm lateral to the crossing point of two lines: a vertical line through the midpoint of distance from the junction of pedicle medial and lateral border to lateral mass, and a horizontal line through the junction between the lateral border of inferior articular process and the posterior branch of transverse process. The pedicle screw was inserted at the entry point. The measurement of the anatomic parameters included the height and width of pedicle, the maximum length of the screw path, the minimum distance from screw path to spinal canal and transverse foramen, and the angle of pedicle screw. The data above were provided to determine the surgical feasibility and screw safety. ResultsThe width of upper, middle, and lower parts of the pedicle was (7.35±0.89), (5.50±1.48), and (3.97±1.01) mm respectively. The pedicle height was (9.94±1.16) mm and maximum length of the screw path was (25.91±1.15) mm. The angle between pedicle screw and coronal plane was (26.95±1.88)° and the angle between pedicle screw and transverse plane was (22.81±1.61)°. The minimum distance from screw path to spinal canal and transverse foramen was (2.72±0.83) mm and (1.98±0.26) mm respectively. ConclusionAccording to the anatomic research, a safe entry point for C2 pedicle screw fixation is determined according to the midpoint of distance from the junction of pedicle medial and lateral border to lateral mass, as well as the junction between the lateral border of inferior articular process and the posterior branch of transverse process, which is confirmed to be effectively and safely performed using the entry point and screw angle of the present study.
【Abstract】Objective To study the anatomy of the hepatic arteries and imitate the way to deal with the hepatic arteries in the living liver transplantation of the left lateral lobe.Methods Thirty normal adult livers were anatomyzed and 30 casting models of livers were observed. The lengths, diameters and distributaries of the hepatic arteries were described.Results The blood supply of the left lateral region came from proper hepatic artery, left hepatic artery and middle hepatic artery. The aberrant arteries included left inferior phrenic artery, left gastric artery and right gastric artery. They branched to supply the upper segment and the inferior segment.Conclusion There are five types of hepatic arteries to supply the left liver lobe. The anatomy of hepatic arteries should be studied and a reasonable approach to gain a liver graft should be designed before transplantation. The hepatic arteries should be dealt with so as to anastomose with recipient hepatic arteries.
Objective To observe and measure the approach next to the erector spinae in the thoracic and lumbar segments of the spine and adjacent anatomical structures by the topographic method, to clarify the positioning method and safe range so as to provide the anatomical basis of the approach for spinal canal decompression. Methods Twelve formaldehyde-treated adult cadaver specimens were selected, including 6 males and 6 females with an average age of 43 years (range, 27-52 years) and with an average height of 166 cm (range, 154-177 cm). The related data of the approach at T1-S1 levels were respectively measured: the distance between the lateral edge of the erector spinae and the spinous process, the length of the approach, the angle between the approach and the horizontal plane, the size of intervertebral foramen, and the vertical distance between the segmental artery and the upper edge of the vertebrae. Results The distance between the lateral edge of the erector spinae and the spinous process ranged from (41.75 ± 3.29) mm to (74.54 ± 7.08) mm. The length of the approach ranged from (66.75 ± 10.81) mm to (97.13 ± 13.35) mm. The angle between the approach and the horizontal plane ranged from (38.38 ± 6.16)° to (53.67 ± 4.40)°. The vertical distance between the segmental artery and the upper edge of the vertebrae ranged from (9.50 ± 0.60) mm to (18.30 ± 1.56) mm. The size of foraminal was also measured. The spinal canal could reach when iliocostalis lateral edge was used as the starting point in the lumbar segments, and longissimus lateral edge as the starting point in the thoracic segments. It was confirmed that there was enough safe space for the spinal decompression without the resection of the articular process. Conclusion The approach next to the erector spinae can reach spinal canal to achieve the purpose of decompression through the intervertebral foramen. The minimally invasive approach is feasible and safe. It has the value of the operative application.
【Abstract】 Objective To investigate the feasibil ity of contralateral C7 nerve transfer via posterior spinal route fortreatment of brachial plexus root avulsion injury by anatomical study. Methods Ten cadaveric specimens of 7 men and3 women were selected, who had no obvious deformity and no tissue defect in neck neutral position. By simulating surgical exploration of brachial plexus injury, the length of contralateral C7 nerve root was elongated by dissecting its anterior and posterior divisions to the distal end, while the length of C7 nerve from the intervertebral foramen to the branching point and the length of the anterior and posterior divisions were measured. By simulating cervical posterior approach, the C7 vertebral plate and T1 spinous process were fully exposed; the hole was made near vertebral body; and the C7 nerve root lengths by posterior vertebra path to the contralateral upper trunk and lower trunk were measured. Results C7 nerve root length was (58.62 ± 8.70) mm; the length of C7 nerve root plus posterior or anterior division was (65.15 ± 9.11) mm and (70.03 ± 10.79) mm, respectively. By posterior spinal route, the distance was (72.12 ± 10.22) mm from the end of C7 nerve to the contralateral upper trunk of brachial plexus, and was (95.21 ± 12.50) mm to the contralateral lower trunk of brachial plexus. Conclusion Contralateral C7 nerve can be transferred to the contralateral side through posterior spinal route and it only needs short bridge nerve or no. The posterior spinal route can effectively prevent from neurovascular injury, so it might be the best surgery approach for the treatment of brachial plexus root avulsion injury.
Objective To investigate the anatomical evidence of low end-to-side anastomosis of median nerve and ulnar nerve in repair of Dejerine Klumpke type paralysis or high ulnar nerve injury. Methods Twelve formaldehyde anticorrosion specimens (24 sides) and 3 fresh specimens (6 sides) were observed. There were 9 males (18 sides) and 6 females(12 sides). The specimen dissected under the microscope. S-shape incision was made at palmar thenar approaching ulnar side, the profundus nervi ulnaris and superficial branch of ulnar nerve were separated through near end of incision, and the recurrent branch of median nerve and comman digital nerve of the ring finger were separated through far end of incision. The distances from pisiform bone to the start point of the recurrent branch of median nerve, and to the start point of comman digital nerve of the ring finger were measured. The width and thickness of the profundus nervi ulnaris and superficial branch of ulnar nerve, and the recurrent branch of median nerve and comman digital nerve of the ring finger were measured, and the cross-sectional area was calculated. The number of nerve fiber was determined with HE staining and argentaffin staining. Results The crosssectional area and the number of nerve fiber were (2.46 ± 1.03) mm2 and 1 305 ± 239 for the profundus nervi ulnaris, (2.62 ± 1.75) mm2 and 1 634 ± 343 for the recurrent branch of median nerve, (1.60 ± 1.39) mm2 and 1 201 ± 235 for the superficial branch of ulnar nerve, and (2.19 ± 0.89) mm2 and 1 362 ± 162 for the comman digital nerve of the ring finger. There were no significant differences (P gt; 0.05) in the cross-sectional area and the number of nerve fiber between the profundus nervi ulnaris and the recurrent branch of median nerve, between the superficial branch of ulnar nerve and the comman digital nerve of the ring finger; and two factors had a l inear correlation (P lt; 0.05) with correlation coefficients of 0.68, 0.66 and 0.56, 0.36. The distances were (36.98 ± 4.93) mm from pisiform bone to the start point of the recurrent branch of median nerve, and (28.35 ± 6.63) mm to the start point of comman digital nerve of the ring finger. Conclusion Low end-to-side anastomosis of median nerve and ulnar nerve has perfect match in the cross-sectional area and the number of nerve fiber.
Objective To provide the anatomic evidences and the choice of tendon graft for anatomic reconstruction of posterolateral complex through the morphological and biomechanical study on posterolateral structures of the knee in normal adult cadavers. Methods Twenty-three fresh lower l imb specimens from voluntary donators and 9 lower l imbs soaked by Formal in were selected for anatomic study on the posterolateral complex of the knee. Six fresh specimens were appl ied to measure the maximum load, intensity of popl iteus tendon, lateral collateral l igament, and popl iteofibular l igament, which were key components of the posterolateral complex. Results Popl iteus musculotendinous junction was located at 7.02-11.52 mm beneath lateral tibial plateau and 8.22-13.94 mm medially to fibular styloid process. The distances from femoral insertion of popl iteus tendon to the lower border of femoral condyle and to posterior edge of femoral condyle were 10.52-14.38 mm and 14.24-26.18 mm, respectively. Popl iteofibular l igament originated from popl iteus musculotendinous junction and ended at fibular styloid process. Lateral collateral l igament was located at 10.54-16.48 mm inferior to fibular styloid process, and the distances from femoral insertion to the lower border of femoral condyle and to posterior edge of femoral condyle were 14.92-19.62 mm and 14.66-27.08 mm, respectively. The maximum load and intensity were 579.60-888.40 N and 20.50-43.70 MPa for popl iteus tendon, were 673.80-1 003.20 N and 24.30-56.40 MPa for lateral collateral l igament, and were 101.56-567.35 N and 8.94-36.16 MPa for popl iteofibular l igament, respectively. Conclusion During anatomical reconstruction of posterolateral complex, the bony tunnel of the key components should be located according to the insertion mentioned above. On the basis of this study, the maximum load and intensity of selectable grafts should exceed 833 N and 36 MPa.
Objective To investigate the blood supply of the ulnar nerve in the elbow region and to design the procedure of anterior transposition of ulnar nerve accompanied with arteries for cubital tunnel syndrome.Methods The vascularity of the ulnar nerve was observed and measured in20adult cadaver upper limb specimens. And the clinical surgical procedure was imitated in 3 adult cadaver upper limb specimens. Results There were three major arteries to supply the ulnar nerve at the elbow region: the superior ulnar collateral artery, the inferior ulnar collateral artery and the posterior ulnar recurrent artery. The distances from arterial origin to the medial epicondyle were 14.2±0.9, 4.2±0.6 and 4.8±1.1 cm respectively. And the total length of the vessels travelling alone with the ulnar nerve were 15.0±1.3,5.1±0.3 and 5.6±0.9 cm. The external diameter of the arteries at the beginning spot were 1.5±0.5, 1.2±0.3 and 1.4±0.5 mm respectively. The perpendicular distance of the three arteries were 1.2±0.5,2.7±0.9 and 1.3±0.5 cm respectively.Conclusion It is feasible to perform anterior transposition of the ulnar nerve accompanied with arteries for cubital tunnel syndrome. And the procedure preserves the blood supply of the ulnar nerve following transposition.
Objective To investigate the anatomic foundation of using main branch of posterior femoral nerve to restore the sensation function of distal basedsural island flap. Methods Thirty cases of adult human cadaver legs fixed by 4%formaldehyde were used. Anatomical investigation of the posterior femoral nerves of lower legs was conducted under surgical microscope to observe their distribution, branches and their relationship with small saphenous vein. Nerve brancheswith diameter more than 0.1 mm were dissected and accounted during observation.The length and diameter of the nerves were measured. Results The main branch of posterior femoral nerve ran downwards from popliteal fossa within superficial fascia along with small saphenous vein. 70% of the main branch of the posterior femoral nerves lay medially to small saphenous vein, and 30% laterally. They wereclassified into 3 types according to their distribution in lower legs: typeⅠ (33.3%) innervated the upper 1/4 region of lower leg (region Ⅰ), type Ⅱ (43.3%) had branches in upper 1/2 region (region Ⅰ and Ⅱ), and type Ⅲ (23.3%) distributed over the upper 3/4 region (region Ⅰ, Ⅱ and Ⅲ). In type Ⅱ, the diameter of the main branches of posterior femoral nerves in the middle of popliteal tossa was 10±04 mm and innervated the posterior upper-middle region (which was the ordirary donor region of distal based sural island flaps) of lower legs with 2.0±0.8 branches, whose diameter was 0.3±0.2 mm and length was 3.5±2.7 mm. The distance between the end of these branches and small saphenous vein was 0.8±0.6 mm. In type Ⅲ, their diameter was 1.2±0.3 mm and innervated the posterior upper-middle region of lower legs with 3.7±1.7 branches, whose diameter was 0.4±0.1 mm and length was 3.7±2.6 mm. The distancebetween the end of these branches and small saphenous vein was 0.8±0.4 mm. Conclusion 66.6% of human main branch of posteriorfemoral nerves (type Ⅱ and type Ⅲ) can be used to restore the sensation of distal based sural island flap through anastomosis with sensor nerve stump of footduring operation.
Objective To provide the anatomic basis for thelag screw placement in the anterior column of the acetabulum. Methods Twenty-two pelvis specimens with 44 acetabula of the native adult cadavers were studied. The anthropometric measurement was performed on 44 acetabula to determine the shape of the transverse section of the anterior column of the acetabulum, the optimal entry point for the lag screw on the outer table of the ilium, the direction of the screw, and the distance from the entry point to the obturator groove. Results The transverse section of the anterior column of the acetabulum was almost triangle-shaped. The path for the lag screw placement was 10.5±0.8 mm in diameter. The optimal entry point on the posterolateral ilium for the screw fixation was found toexist 9.2±2.4 mm superior to the line between the anterior superior iliac spine and the greater sciatic notch and 38.5±3.8 mm superior to the greater sciatic notch. The distance from the entry point to the obturator groove was 84.1±6.2 mm. The inclination of the lag screw was 54.2±5.5° at the caudal direction in the sagittal plane and 40.7±3.8° in the horizontal plane. The device for the safe screw placement in the anterior column was designed. Conclusion The above datacan facilitate an insertion of one 6.5 mm lag screw into the anterior acetabular column and minimize the risk of articular violation or cortical penetration, which has a narrow margin of safety. The safe length of the lag screw should be 70 mm.The optimal entry point on the posterolateral ilium for the screw fixationis determined to be 10 mm superior to the line between the anterior superior iliac spine and the greater sciatic notch and 40 mm superior to the greater sciatic notch. The inclination of the lag screw should be 55° at the caudal direction in the sagittal plane and 40° in the horizontal plane. It is safe to place thelag screw in the anterior column with the help of the targeting device.
Objective To provide the anatomic bases for clinical application of the second dorsal metacarpal artery(SDMA) island flap with double pivot points. Methods The origin,branches and distribution of the recurrent cutaneous branch of the SDMA were observed in 30 adult fresh cadaver specimens, which were illustrated with special dye.Eighteen cases of skin defets of the thumb were repaired with the SDMA island flap. The defect locations were the dorsal part in 11 cases and palmar part in 7 cases, including 3 cases of defect in association with long pollical extensor defect and 2 cases of defect in association with dorsal skin defect of proximal finger. The flap area ranged from 2 cm×3 cmto 3 cm×5 cm. Results The appearance of therecurrent cutaneous branch of the SDMA was observed in all cases(100%), which originated 0.5±0.2 cm distant from the distal intersectiones between the SDMA and the index extensor and disappeared 1.2±0.5 cm distant from the proximal metacarpophalangeal joint. The branches of 1.7±0.7 were seen with a longitudinal fan-like distributionforward proximal part on the deep surface of the dorsal superficial vein. The exradius and the length of the recurrent cutaneous branch of the SDMA were 0.3±0.1 mm and 6.5±0.8 mm, respectively. The transplanted flaps survived in all cases and 16 cases were followed up for 8-14 months. The colour and appearance of the skin were satisfactory. The two-point discriminations were 0.9 mm in 3 cases by bridging digital nerve and 1.1 mm in 9 cases by anastomosing dorsal digital nerve; while the two-point discrimination was 13-15 mm in 4 cases without anastomosing nerve. Conclusion The origin,branches and distribution of the recurrent cutaneous branch of the SDMA is constant, which provide a potentially longer pedicle and increase the possibility to rotate the flap and also avoid the donor skin defect of rotation of the flap.