Objective To explore the influence of discectomy and artificial disc replacement on the upper lumbar facet joint and to provide the evidence for use of artificial disc replacement. Methods Under the loads of 200-2 000 N axis pressure and 1-10 Nm back-extending/side-bending pressure on the 7 fresh adult corpses, the pressure of L3,4facet joint was measured in the case of L4,5disc integrity, discectomy and artificial disc replacement and the statistical analysis was done.ResultsUnder the same load (axis, back-extending/side bending), there were significant differences (Plt;0.01) in the pressure of upper lumbar facet jointboth between disc integrity and discectomy and between discectomy and artificial disc replacement, and there was no difference(Pgt;0.05) between disc integrity and artificial disc replacement. Conclusion The stress ofupper lumbar facet joint reduced after discectomy, it implies that simply discectomy may change biomechanics of lumbar and lead to secondary lumbar structure degeneration. The stress of upper lumbar facet joint is close to the normal value after artificial disc replancement, it implies that artificial disc replacement may protect lumbar structure. It provides some biomechanics foundation and evidence for artificial disc replacement.
Objective To investigate the cl inical effect of cervical artificial disc replacement (CADR) on twosegment cervical spondylosis and to research its influences on the range of motion (ROM) of the diseased segments and theadjacent superior and inferior segments. Methods From September 2004 to February 2007, 7 cases with cervical spondylosis at C4,5 and C5,6 were treated with CADR using Bryan artificial disc prosthesis, including 4 males and 3 females aged 30-45 years old (average 38.5 years old). All the patients had cervicodynia in various degrees, pain and numbness of l imbs and decreased muscle strength, including 3 cases of cervical spondylotic radiculopathy, 3 of cervical spondylotic myelopathy and 1 of mixed cervical spondylosis. The course of disease was 12-54 months (average 27 months). Preoperatively, X-ray films revealed the intervertebral space of C4, 5 and C5,6 was narrowed and the cervical curve became straight, CT or MRI showed the intervertebral disk hernia of C4, 5 and C5,6, and the hyperostosis of vertebral margin compressed nerve root or spinal cord. All the patients had no response to the preopratively conservative treatment. JOA score and ROM of the diseased segments and the adjacent superior and inferior segments were compared before and after operation. Results All the patients survived the perioperative period, without hoarse voice, muscle spasm, dysphagia and cervicodynia. X-ray films showed the implanted prosthesis was well located, the height of intervertebral space was normal, and no prosthesis loosening, prosthesis migration and infection occurred 12 months after operation. All the 7 cases were followed up for 12-41 months (average 26.7 months). Cervicodynia and l imbs’pain and numbness disappeared, and muscle strength was improved obviously. The JOA score before and during the followup period was (8.35 ± 1.27) and (14.65 ± 1.61) points, respectively, indicating there was a significant difference (P lt; 0.05). For the ROM of C4,5 and C5,6, it was (8.38 ± 0.48)° and (9.16 ± 0.54)° before operation, respectively, and it increased to (11.15 ± 0.65)° and (12.75 ± 0.73)° after operation, respectively, showing there was a significant difference (P lt; 0.05). The ROM at C3,4 and C6,7 before operation was (9.71 ± 0.76)° and (12.39 ± 0.58)°, espectively, while it was improved to (10.26 ± 0.47)° and (13.67 ± 0.71)° after operation, respectively, indicating there were no significant differences between before and after operation (P gt; 0.05). Conclusion The appl ication of Bryan Disc CADR for two-segment cervical spondylosis has satisfying therapeutic effects, can improve the ROM of diseased segments obviously, and has minor influences on the ROM of adjacent superior and inferior segment.
Objective To study operative methods of treating upper cervical spine instability without injury. Methods Twentythree cases were treated by internal fixation with autologous bone grafts. Atlantoaxial arthrodesis were performed in 10 cases with Apofix interlaminar clamp(5 cases), Atlas cable system(3 cases) and Brookes(2 cases). Occipitocervical fusion were performed in the other 13 cases by using of CD-cervical(3 cases), Cervifix(8 cases) and Ustick fixation(2cases). Results All the 23 cases were followed up for 2.5 years in average (ranged from 6 months to 5 years). Solid arthrodesis was obtained in all 23 cases . Six months after operation, of the 20 cases with preoperation nervous lesion, improvement was achieved in 16 cases. According to JOA standard and Hirabashiformula,the rate of improvement was 27.1%.Conclusion Posterior fusion is recommended for upper cervical unstability.
Objective To discuss the concept of ulnar tunnel at thewrist, the types, causes, traits of compression, diagnosis, and clinical significance of ulnar tunnel syndrome(UTS). Methods Thirty-nine cases diagnosed as having UTS from 1986 were retrospectively reviewed combined with previous relevant literature. Results Ulnar tunnel included Guyon’s canal, pisohamate tunnel and hypothenar segment. There were 8 types andmany causes of UTS. Some patients had compression in more than one zones and might be associated with carpal tunnel syndrome or cubital tunnel syndrome. UTS could be diagnosed through clinical manifestations and electrophysiological examination. Conclusion Defining the concept of ulnar tunnel and the knowledge of the complexity and rarity of UTS can effectively guide diagnosis and treatment.
Objective To discuss the therapeutic effect of distal fixed modular femoral prosthesis for the hip prosthesis revision. Methods Between August 2004 and May 2008, cementless modular femoral prosthesis was used for hip prosthesis revision in 21 cases. There were 9 males and 12 females, aged from 49 to 72 years (mean, 64.6 years). The timefrom revision to total hip arthroplasty was 2 to 18 years (mean, 11.7 years). The causes of revision included aseptic loosening in 19 cases (5 cases were periprosthetic femoral fracture), and deep infection in 2 cases. First revision was given in all patients. Preoperative Harris score was 41.8 ± 3.5; pain visual analogue score (VAS) was 7.62 ± 0.86. Results All patients achieved heal ing of incision by first intention, and no deep venous thrombosis and nerve injury occurred. Twenty-one cases were followed up 2 to 6 years with an average of 4.3 years. No prosthetic loosening or infection occurred. Bone ingrowth was observed around the implant during the follow-up period. At last follow-up, 2 cases had femoral stem subsidence without obvious hip pain and other symptoms, and no special treatment was given. Harris score was 82.7 ± 3.3 and VAS score was 0.19 ± 0.51 at last follow-up, showing significant differences when compared with those before operation (P lt; 0.05). Conclusion The short-term result of modular femoral prosthesis is satisfactory in hip prosthesis revision, and it can improve the hip function and rel ieve the pain greatly.
Objective?To discuss the clinical application of total hip arthroplasty (THA) with collum femoris preserving (CFP) prosthesis and to analyze the mid-term effectiveness.?Methods?Between January 2004 and February 2007, 45 patients (48 hips) underwent THA with CFP prosthesis. There were 29 males (31 hips) and 16 females (17 hips) with an average age of 48.8 years (range, 38-60 years), including 20 left hips, 22 right hips, and 3 bilateral hips. The causes of hip replacement were osteoarthritis (20 cases), avascular necrosis of femoral head (13 cases), dysplasia (4 cases), rheumatoid arthritis (3 cases), post-traumatic osteoarthritis (2 cases), ankylosing spondylitis (2 cases), and Perths disease (1 case). The average disease duration was 6.1 years (range, 2-13 years). Harris scores, visual analogue scale (VAS) score, and the hip range of motion (ROM) were recorded at pre- and post-operation. The X-ray films were taken at pre- and post-operation to observe the position, loosening of the prosthesis, and ectopic ossification. The gait of patients were also evaluated during follow-up. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients.?Results?All 45 patients were followed up 5-8 years with an average of 6.4 years. All the incisions healed by first intention. No infection, hip dislocation, nerve injury, or deep vein thrombosis occurred. Six cleavage fractures (13.3%) of the lateral femoral diaphysis at the distal prosthesis occurred during operation, which healed at 8 months postoperatively without any treatment. Mild ectopic ossification occurred in 4 patients (8.9%) who had no discomfort. Five patients (11.1%) had bone mineral density loss in the region of the proximal femur. The survival rates of the cups and stems were all 100% at last follow-up. The results of Harris score, VAS score, and ROM of the hip joint at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P lt; 0.05). No significant difference was found in VAS score and ROM of the hip joint between at 1 year postoperatively and at last follow-up (P gt; 0.05) except the Harris score (P lt; 0.05). According to Harris functional assessment at last follow-up, the results were excellent in 31 hips, good in 11 hips, and fair in 6 hips with an excellent and good rate of 87.5%. The physiological role, body pain, and total health scores were significantly lower than the reference value of urban men from Sichuan province (P lt; 0.05), but no significant difference was found in the other scores of the SF-36 when compared with the reference value (P gt; 0.05).?Conclusion?THA with CFP prosthesis is a good option for the young patient with complete collum femoris and without osteoporosis, and can achieve good mid-term effectiveness.
Objective To evaluate the mid-term effectiveness of two-stage hip prosthesis revision in the treatment of infection after hip arthroplasty. Methods Between April 2002 and November 2006, 12 cases of infection after hip arthroplasty were treated. There were 5 males and 7 females, aged from 47 to 72 years (mean, 59.8 years). The femoral head arthroplasty wasperformed in 2 cases and total hip arthroplasty in 10 cases. Infection occurred 1 to 67 months after arthroplasty. According to the Segawa classification criteria, infections included type 2 in 1 case, type 3 in 2 cases, and type 4 in 9 cases. The preoperative Harris score was 36.7 ± 6.1. Nine cases had elevated C reactive protein and 10 cases had elevated erythrocyte sedimentation rate. The results of bacterial culture were positive in 8 cases and negative in 4 cases. After the removal of the infected prosthesis and thorough debridement, antibiotic-loaded cement spacers or infected therapeutic temporary prosthesis were used as placeholders, and then the anti-infection treatments were given after operations; two-stage hip prosthesis revisions were performed 3 to 10 months after debridement. Results In 1 patient who failed to control infection after debridement, infection was controlled after the second debridement and the antibiotic-loaded cement spacer as placeholder. Other patients achieved heal ing of incision by first intention, and no compl ication such as deep venous thrombosis and nerve injury occurred. All patients were followed up 3 to 8 years after revision (mean, 5.4 years). During the follow-up, no infection recurrence and joint dislocation occurred. Dull pain was present in 2 cases during activity and mild claudication in 3 cases at last follow-up. The Harris score was 81.6 ± 4.5, showing significant difference (t=52.696, P=0.000) when compared with preoperative score. The X-ray films showed that noprosthesis loosening and obvious subsidence were observed, and bone graft healed. Conclusion The two-stage hip prosthesis revision has good infection control rate and mid-term effectiveness in treatment of infection after hip arthroplasty.
Objective To investigate the effect of the anterior cruciate l igament (ACL) rupture on the biomechanics of the lateral collateral l igament (LCL). Methods The specimens in this experiment were knee joints from 6 normal fresh adult male cadavers which was donated voluntarily, aged of 26-35 years with an average of 31.4 years. The knee joints were dissymmetry with 3 in left and right sides respectively. At first, all the 6 specimens lying on the self-made movement tooting, whose LCL straining were measured by strain gauges at different angles (0, 30, 60 and 90°) under axial loads of 400 N by e-testing machine for simulation of the normal knee joint force, were regarded as the intact ACL group. Then, the ACL in all 6 specimens were cut off completely as the deficiency group and did the same step. Results The strain of the LCL were as follows at 0, 30, 60 and 90°: (0.00 ± 1.63), (—17.2 ± 8.57), (—24.00 ± 4.80) and (26.50 ± 4.65) με in intact ACL group; (0.75 ± 8.22), (— 52.75 ± 3.33), (24.30 ± 4.99) and (26.30 ± 4.27) με in deficiency group. There was no significant difference at 0° and 90° flexion (P gt; 0.05), but significant difference at 30° and 60° flexion (P lt; 0.05) between the two groups. Conclusion The rupture of the ACL has significantly effect on the strain of the LCL which suffering abnormal load in the state at 30° and 60° flexion. At 30° flexion the relaxation of the LCL increased, which means the possibil ity of the injury of the LCL is rare; and at 60° flexion the LCL become very tense and thereby at the high risk of instabil ity.