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F Kandziora

Publications and source records attributed to F Kandziora.

32 records · Page 2Linked to original sources

[Biomechanical study of angle-stable anterior atlanto-axial spondylodesis plate].

The optimum fixation method to achieve atlantoaxial fusion after odontoid resection is still subject to discussion. Isolated posterior surgical procedures for treatment of irreducible atlantoaxial kyphosis with spinal cord compression are associated with a high rate of morbidity and mortality. Transoral atlantoaxial plate fixation has been described by Harms as a fixation technique after odontoid resection. The purpose of this study was to compare biomechanically a new anterior atlantoaxial locking plate (AALP) with the Harms plate and the atlantoaxial transarticular screw fixation described by Magerl. Sixteen human cadaver craniocervical specimens were tested in flexion, extension, rotation, and bending with a nondestructive flexibility method using a nonconstrained testing apparatus. Five different groups were examined: (1) control group (intact) (n = 16), (2) unstable group (after dissection of the atlantoaxial ligaments and odontoidectomy) (n = 16), (3) Harms group (transoral atlantoaxial plate fixation) (n = 8), (4) AALP group (anterior atlantoaxial locking plate fixation) (n = 8), and (5) Magerl group (transarticular atlantoaxial screw fixation) (n = 16). Stiffness in any direction was significantly higher in the AALP specimens and those fixated with the Magerl method than in the Harms, control, or unstable specimens. The difference in stiffness between the AALP and Magerl reconstruction groups was not statistically significant. Experimentally, the AALP was significantly stiffer than the Harms plate. The AALP provided stiffness equal to transarticular screw fixation according to Magerl. A question that cannot be answered by this in vitro study concerns the level of rigidity required to obtain long-term stability and fusion by atlantoaxial fixation methods. However, it may be assumed that the more spinal motion is eliminated the greater the chance of definite spinal fusion. Therefore, it seems reasonable that the most reliable and rigid fixation method would be the method of choice.

Aged↗

[Atlanto-axial kyphosis].

Atlantoaxial kyphosis (AAK) is a rare sagittal deformity of the occiptoatlantoaxial junction. It is defined as a subgroup of anterior translatory atlantoaxial instability. AAK is a symptom of several ligamentours or bony disorders of the craniocervical junction; however, rheumatoid arthritis and trauma are the most common causes for AAK. AAK can be diagnosed on lateral radiographic views of the upper cervical spine if the angle between McGregor's line and the atlas plane is less than-15 degrees or the atlas-axis angle is greater 105 degrees. Treatment modalities for AAK depend on the ability to reduce the deformity. If closed reduction is achieved, posterior atlantoaxial fusion by sublaminar wiring according to Brooks or transarticular screw fixation according to Magerl are possible choices. Irreducible AAK can be treated with a combined transoral decompression, anterior plating according to Harms, and posterior wiring according to Brooks. This staged therapy for AAK was successful in our rheumatoid patient population with AAK.

Atlanto-Axial Joint↗

The EndoPearl device increases fixation strength and eliminates construct slippage of hamstring tendon grafts with interference screw fixation.

PURPOSE: The EndoPearl (Linvatec, Largo, FL), a biodegradable device to augment the femoral interference screw fixation of hamstring tendon grafts has been developed. The first objective of this study was to compare the initial fixation strength of quadrupled hamstring tendons and biodegradable interference screw fixation with and without the application of the EndoPearl device. The second objective was to determine the influence of the EndoPearl device on the fatigue behavior under incremental cyclic loading conditions in a simulation of critical fixation conditions. TYPE OF STUDY: Biomechanical study. METHODS: Fresh human hamstring tendons were harvested and grafts were fixed with biodegradable poly-L-lactide interference screws. Twenty proximal calf tibias were used to compare the initial fixation strength of the study and the control group. In the study group, the EndoPearl device was secured to the graft using two No. 5 Ethibond sutures (Ethicon, Somerville, NJ). Specimens were loaded until failure in a materials testing machine. For cyclic testing, human hamstring tendons and 20 distal porcine femurs were used. Critical graft fixation conditions were simulated by increasing tunnel diameter 2 mm over the graft diameter. Grafts were loaded progressively in increments of 100 N until failure; 100 cycles were applied per load increment. RESULTS: Graft fixation with the additional EndoPearl device had a significantly higher maximum load to failure (658.9 +/- 118.1 N v 385.9 +/- 185.6 N, P =.003) and stiffness (41.7 +/- 11 N/mm v 25.7 +/- 8.5 N/mm). Graft fixation with the EndoPearl device sustained a significant higher total number of cycles (388.5 +/- 125.6) compared with the control group (152.8 +/- 144.9, P =.002). CONCLUSIONS: We demonstrated that the augmentation of a hamstring tendon graft with the EndoPearl device increases interference screw fixation strength significantly. Under dynamic loading conditions, specimens of the study group sustained substantially higher loads and a larger number of cycles, which indicates a greater resistance to graft slippage. The application of the EndoPearl device may also allow for a secure soft-tissue graft fixation with interference screws in cases of critical fixation conditions.

Absorbable Implants↗

Screw placement in transoral atlantoaxial plate systems: an anatomical study.

OBJECT: The placement of an anterior atlantoaxial plate after transoral odontoid resection has been described by Harms. Recently, the authors of biomechanical and clinical studies have shown that this procedure, especially in combination with posterior wiring, is a good alternative to established, isolated posterior atlantoaxial fixation techniques. Reports on the anatomy of the atlas and axis primarily focus on the posterior surgical approach. Scarce research regarding the quantitative anatomy of the anterior aspect of C-1 and C-2 has been reported. This study was undertaken to measure relevant dimensions of C-1 and C-2 and their relation to the anterior transoral approach. The aim of the study was to determine "safe zones" for screw placement in anterior atlantoaxial plate fixation. METHOD: Fifty human dry C-1 and C-2 vertebrae were obtained for direct anatomical, radiographic, and computerized tomography (CT) measurements. Thirty-two linear and four angular parameters were evaluated. All measurements were made using a digital caliper, ruler, or goniometer. Anatomical measurements were correlated with radiographic (anteroposterior, lateral, and craniocaudal) and CT (0.5-mm-slice thickness) measurements of the corresponding vertebrae. Additionally, bone mineral density (BMD) measurements of C-1 and C-2 were obtained in 20 patients. A safe zone for anterior screw placement in an atlas of bilateral trapezoid shape could be characterized. The average medial and lateral height of the trapezoid was 4.1 +/- 1.01 mm (range 1.4-6.7 mm) and 12.9 +/- 1.73 mm (range 8.7-17.4 mm), respectively. The distance between the sagittal plane and the medial and lateral walls of the trapezoid was 10.2 +/- 1.42 mm (range 8.9-12.8 mm) and 23.5 +/- 2.98 mm (range 21.7-30.7 mm), respectively. The average depth of the lateral masses was 22.3 +/- 2.04 mm (range 17.0-26.7 mm) in the sagittal plane. The average BMD in the safe zone of C-1 was 0.89 +/- 0.11 g/cm3 (range 0.75-1.01 g/cm3). Bone mineral density measurements at C-2 revealed a spheroid zone of low density at the basis of the dens (0.68 +/- 0.09 g/cm3). In contrast, high zones of BMD were found near the articular surfaces (C1-2: 0.97 +/- 0.11 g/cm3; C2-3: 0.94 +/- 0.12 g/cm3). The safe zone for anterior axis screw placement was V-shaped, limited cranially by a zone of low bone density and laterally by the vertebral artery groove. Correlations between radiographic and anatomical measurements were generally good (r2 = 0.78-0.95), but they were higher between CT and anatomical measurements (r2 = 0.86-0.99). CONCLUSIONS: A quantitative understanding of the anterior anatomy of C-1 and C-2 is necessary when considering anterior atlantoaxial plate fixation after transoral odontoid resection. In this study the authors defined safe zones for anterior atlas and axis screw placement. The anterior atlantoaxial plate, as originally described by Harms, only partially respects these safe zones.

Adult↗

Transoral decompression, anterior plate fixation, and posterior wire fusion for irreducible atlantoaxial kyphosis in rheumatoid arthritis.

STUDY DESIGN: Fifteen consecutive patients with irreducible atlantoaxial kyphosis caused by rheumatoid arthritis were treated by combined transoral odontoid resection, anterior plate fixation, and posterior wire fusion. OBJECTIVES: To investigate the clinical results of this new surgical procedure. SUMMARY AND BACKGROUND DATA: Irreducible atlantoaxial kyphosis in rheumatoid arthritis results from a destruction of the craniocervical joint ligaments and the anterior aspects of the lateral atlantoaxial joints. The development of a paradental synovial pannus and atlantoaxial joint impaction prevents reduction by conservative treatment, such as skull traction. Posterior surgical procedures for the treatment of the irreducible atlantoaxial kyphosis with spinal cord compression have been associated with high morbidity and mortality. METHODS: Fifteen consecutive patients were treated by transoral odontoid resection. The fixation was performed with anterior plating, according to the method of Harms in combination with posterior wire fusion according to Brooks. Before and after surgery, evaluation was performed using the parameters of pain (visual analog scale), range of motion, and subjective assessment of improvement and the Health Assessment Questionnaire. The neurologic deficit was defined according to the classifications proposed by Ranawat, Frankel, and Nurwick. Plain radiographs, including lateral flexion and extension views, and magnetic resonance scans were obtained. RESULTS: No perioperative fatality occurred. The average clinical and radiographic follow-up was 50.7 +/- 15.6 months (range, 26-77). Postoperative pain was relieved (mean pain score before surgery, 7.9 +/- 1.87; after surgery, 3.8 +/- 1.27), and the range of motion of all patients increased (mean 21.5 +/- 14.0 degrees for rotation; mean 17.2 +/- 5. 54 degrees for bending). The score on the Health Assessment Questionnaire increased in three patients, remained unchanged in three and decreased in six patients (three had died). All patients improved at least one Ranawat level after surgery, except a patient in Ranawat Class II, whose condition remained unchanged. All patients were satisfied with the procedure and reported subjective improvement. CONCLUSION: Transoral plate fixation combined with posterior wire fixation after transoral odontoid resectionis an effective, reliable, and safe procedure for the treatment of irreducible atlantoaxial kyphosis in rheumatoid arthritis.

Adult↗

Biomechanical assessment of transoral plate fixation for atlantoaxial instability.

STUDY DESIGN: In an experimental study using human cadaver specimens the biomechanical data of anterior atlantoaxial plating according to Harms were evaluated. OBJECTIVES: The purpose of this study was to evaluate this method biomechanically. SUMMARY AND BACKGROUND DATA: The optimum fixation method to achieve fusion at the atlantoaxial joint after odontoid resection is still a matter of discussion. Isolated posterior surgical procedures for treatment of irreducible atlantoaxial kyphosis with spinal cord compression are associated with high rates of morbidity and mortality. Transoral atlantoaxial plate fixation has been designed by Harms as a fixation technique after odontoid resection. In a modification, this procedure has been combined with the posterior wire fusion according to Brooks. METHOD: Eight human cadaver craniocervical specimens were tested in flexion, extension, rotation, and bending with a nondestructive flexibility method using a nonconstrained testing apparatus. Five different groups were examined: 1) control group (intact); 2) unstable group (after dissection of the atlantoaxial ligaments and odontoidectomy), 3) Harms group (transoral atlantoaxial plate fixation) 4) Harms-Brooks group (transoral atlantoaxial plate fixation and dorsal atlantoaxial wire fixation); and 5) Magerl group (transarticular atlantoaxial screw fixation). In a second experimental series, failure loads of the Harms-Brooks and the Magerl fixation methods were determined. RESULTS: The angular displacement of the Harms-Brooks group and the Magerl group was less than in any other group. Stiffness values at 0-3.0 Nm loads in any direction were larger for the Harms-Brooks-and Magerl-fixated specimens than for the Harms, control, or unstable specimens. No statistically significant difference was observed between Harms-Brooks and Magerl reconstruction stiffness. Ultimate failure load in the Harms-Brooks group was higher than in the Magerl group. CONCLUSIONS: Experimentally, isolated anterior atlantoaxial plating was less stable than the combined reconstruction procedures. Transoral plate fixation according to Harms in combination with posterior wire fixation according to Brooks provided a failure load and stiffness equal to transarticular screw fixation according to Magerl.

Aged↗

Stage-related surgery for cervical spine instability in rheumatoid arthritis.

Thirty-six consecutive patients with cervical spine instability due to rheumatoid arthritis (RA) were treated surgically according to a stage-related therapeutic concept. The aim of this study was to investigate the clinical results of these procedures. The initial change in RA of the cervical spine is atlanto-axial instability (AAI) due to incompetence of the cranio-cervical junction ligaments, followed by development of a peridontoid mass of granulation tissue. This results in inflammatory involvement of, and excessive dynamic forces on, the lateral masses of C1 and C2, leading to irreducible atlanto-axial kyphosis (AAK). Finally, cranial settling (CS) accompanied by subaxial subluxation (SAS) occurs. According to these three separate pathological and radiological lesions, the patients were divided into three therapeutic groups. Group I comprised 14 patients with isolated anterior AAI, who were treated by posterior wire fusion. Group II comprised 15 patients with irreducible AAK, who were treated by transoral odontoid resection. The fixation was done using anterior plating according to Harms in combination with posterior wire fusion according to Brooks. Group III comprised seven patients with CS and additional SAS, who were treated with occipito-cervical fusion. Pre- and postoperatively, evaluation was performed using the parameters pain (visual analog scale), range of motion (ROM), subjective improvement and Health Assessment Questionnaire (HAQ). The neurologic deficit was defined according to the classification proposed by Ranawat. Radiographs including lateral flexion and extension views, and MRI scans were obtained. The average clinical and radiographic follow-up of all patients was 50.7 +/- 19.3 months (range 21-96 months). No perioperative fatality occurred. Postoperative pain was significantly relieved in all groups (P < 0.001). In group II a slight improvement in the HAQ was obtained. In groups I and II the ROM of all patients increased significantly (average gain of motion in group I: 11.3 degrees +/- 7. 8 degrees for rotation; 7.8 degrees +/- 5.6 degrees for bending; average gain of motion in group II: 21.5 degrees +/- 14.0 degrees for rotation; 17.2 degrees +/- 5.5 degrees for bending), while it decreased significantly in group III (10.7 degrees +/- 18.1 degrees for rotation; 6.7 degrees +/- 18.5 degrees for bending). Preoperatively 27 patients had a manifest neurologic deficit. At follow-up four patients remained unchanged, all others improved by at least one Ranawat class. All patients, except one, showed solid bony fusion. According to the significantly improved postoperative subjective self-assessment and the clinical and radiological parameters, transoral plate fixation combined with posterior wire fixation after transoral odontoid resection represents an effective reliable and safe procedure for the treatment of irreducible AAK in rheumatoid arthritis.

Aged↗

[Radio-lunar Mannerfelt arthrodesis in rheumatoid arthritis].

PURPOSE: We present data of 27 radiolunate and 23 Mannerfelt arthrodeses in patients with rheumatoid arthritis. METHOD AND CLINICAL MATERIAL: Benefits of surgery, i.e. the reduction of pain, swelling, tenderness, and signs of instability as well as radiographic findings of carpal height, carpal collapse, progression of rheumatoid disease beyond the site of wrist fusion were assessed after a mean time of 44 months. RESULTS: Wrist pain and swelling were better managed by Mannerfelt than by radiolunate arthrodesis. Average grip strength of wrists with radiolunate fusion exceeded the strength developed in wrists with Mannerfelt-fusion. However, grip strength of wrists with Mannerfelt-fusion was greater than in the opposite unfused hand, while this was not found in wrists with radiolunate arthrodesis. Postoperative improvements in hand intensive activities were more frequent in the radiolunate fusion population. CONCLUSION: Advancement of carpal degeneration in radiolunate wrist fusions beyond the fusion site may indicate a rising number of symptomatic wrists with increase of follow-up time. Our results have led us to suggest radiolunate fusion for the non-dominant hand in patients with slow carpal progression of rheumatoid disease and especially if complete wrist fusion of the opposite--often dominant hand--has already been performed.

Adult↗

[Combined arthroscopic and radiation synovectomy in rheumatoid arthritis].

In rheumatoid arthritis of the knee joint good results are obtained using arthroscopic synovectomy or radiation synovectomy. Aim of our study was to investigate, whether the combination of these two minimal invasive interventions achieves better results. First we performed arthroscopic synovectomy of the knee joint followed by radiation synovectomy with application of 111-222 MBq Yttrium-90 6 weeks later. In a prospective randomised clinical trial between 1987 and 1991 we performed radiation synovectomy on 22 knee joints and combined arthroscopic and radiation synovectomy on 26 knee joints. We explored the patients preoperatively, 6 weeks and 6 months postoperatively. In 1996 we evaluated 141 knee joints in a retrospective clinical trial. 90 Knee joints had been treated with the combined therapy, 39 only with radiation synovectomy and 12 only with arthroscopic synovectomy. Depending on the three different therapeutic interventions, the patients were classified into midterm (3-5 years) and long-term (6-8 years) observation groups. The trials are based on the standardized ARO-Questionnaire of the knee joint, the modified ARO Knee-Score and the radiological grading according to Larsen, Dale and Eek. In the prospective clinical trial we found significant better results for patients treated with the combined therapy than for patients treated with radiation synovectomy only regarding the parameter swelling, effusion, range of motion, pain and Knee-Score. In the long-term results of the retrospective clinical trial the patients treated with the combined therapy showed a significant better outcome for the parameters pain, swelling and Knee-Score, than the patients treated with radiation synovectomy. Although no statistically significant difference was found comparing the results of the combined therapy with arthroscopic synovectomy, an improvement of the clinical outcome can be observed performing arthroscopic synovectomy followed by radiation synovectomy. In the treatment of rheumatoid arthritis of the knee joint a better outcome is achieved performing combined arthroscopic and radiation synovectomy than performing only one of the methods.

Arthritis, Rheumatoid↗

[Acetabular reconstruction using acetabular reinforcement rings].

Reviewing the literature the revision arthroplasty of the hip joint with acetabular reinforcement rings shows good results concerning a follow-up period of six years in comparison with cemented or non-cemented primary implants. We use different acetabular reinforcement rings with differentiated indications. The primary assignment is the secure fixation of the ring to the vital bone. The acetabular bone defect is filled with autogenous or homogeneous bone grafts. The increasing number of massive acetabular defects made us develop a new acetabular reinforcement ring. It allows a better fixation than the Burch-Schneider Ring and is cheaper than the individual acetabular implant. Since 1988 we performed 262 revision arthroplasty with acetabular reinforcement rings. Until 1996 we evaluated 174 reinforcement rings (41 Müller rings, 72 Ganz rings, 41 Burch-Schneider rings, 6 RS or RSH ring, 5 individual acetabular implants). After an average follow-up period of 5.6 years a radiological or clinical loosening of the acetabular component occurred in only 6 patients (3.4%). To reach a better comparison of the surgical results we developed a score, which differentiate checks the operative goals. On plane pelvic radiographs we checked the reconstruction of the rotation center, the demarcation of the acetabular component and the outcome of the bone transplant.

Acetabulum↗

Arthroscopic labrum refixation for post-traumatic anterior shoulder instability: suture anchor versus transglenoid fixation technique.

SUMMARY: The aim of this retrospective study was to compare recurrence rates following transglenoid labrum refixation or fixation using the suture anchor (FASTak, Arthrex, Naples, FL) technique. Additionally, parameters that apparently influence the rate of redislocation were investigated. There were 163 patients with post-traumatic anterior shoulder instability treated with an arthroscopic labrum refixation; 108 patients (66.3%) were stabilized with the transglenoid suture technique (group I) and 55 patients (33. 7%) with the suture anchor (FASTak) technique (group II). The average follow-up was 4.5 years (range, 2.0 to 7.9 years) in group I and 3.2 years (range, 2.0 to 5.0 years) in group II. The Rowe score increased from a preoperative average of 35.0 points in group I and 35.4 points in group II to a postoperative average of 68.3 points in group I and 84.6 points in group II (P <.01). There was recurrence in 35 patients (32.4%) in group I and 9 patients (16.4%) in group II (P <.05). All incidents of redislocation occurred during the first 21 postoperative months; 58.4% of the patients (n = 63) in group I and 16.4% of the patients in group II (n = 9) had to reduce their sporting activity (P <.001). Independent of the type of surgery, there was a significant correlation of the postoperative rate of redislocation and age (P <.001), number of preoperative dislocations (P <.01), and degree of labrum lesion (P <.001). No correlation with the rate of redislocation was shown for gender, handedness, dislocation-operation interval, degree of Hill-Sachs lesion, or number of transglenoid sutures or anchors. Concerning post-traumatic anterior shoulder instability, the arthroscopic labrum reconstruction with the suture anchor (FASTak) technique was superior to the transglenoid technique but has not yet achieved the level of success obtained by open surgery. With fewer than 5 preoperative redislocations after a first traumatic shoulder dislocation, the arthroscopic treatment is recommended. In cases of more frequent preoperative dislocations, open surgery in combination with a capsular shift should be performed.

Adult↗

[Arthroscopic labral reconstruction for anterior shoulder instability. Failure analysis in 187 patients].

UNLABELLED: Comparing open with arthroscopic labral reconstruction for anterior shoulder instability we found a higher recurrence rate after arthroscopic capsulolabral repair. The aim of this study was, to analyse the reasons for recurrent instability after arthroscopic labral repair. MATERIALS AND METHODS: Between 1989 and 1995 we performed a arthroscopic labral reconstruction on 187 patients with anterior shoulder instability. 118 patients (63%) were treated with a transglenoid suture technique and 69 patient (37%) with a suture anchor technique. The average age at the time of the operation was 26.4 +/- 6.3 years (14-52 years). There were 41 women (21.9%) and 146 men (78.1%). RESULTS: The minimum follow-up was 18 months. The average follow-up was 3.7 +/- 1.1 years. The average Rowe Score increased from 34.7 points (0-75) preoperatively to 75.3 points (15-100) postoperatively. There were 47 (25.1%) excellent. 76 (40.6%) good, 21 (11.3%) fair, and 43 (23.0%) poor results. 105 patients (56.1%) regained their preoperative level of activity. 50 patients (26.7%) had recurrent subluxations or dislocations postoperatively. All failures occurred within two years (0.5-21 months) after the operation. Failure rates were associated with the patients age (p < 0.001), the level of activity (p < 0.05), the number of the preoperative dislocations (p < 0.01), the degree of the labral lesion (p < 0.001), and the operation method (p < 0.05). No correlation was found for the parameters sex, handiness, time between luxation and operation, size of Hill-Sachs-lesion and numbers of used sutures or anchors. CONCLUSION: We prefer the arthroscopic suture anchor technique if there are less than 5 preoperative dislocation and a type 1 or 2 labral lesion. If there are more than 5 preoperative dislocations and a degenerative labrum defect we favor the open Bankart repair technique.

Adolescent↗

[Arthroscopic reconstruction of the anterior cruciate ligament with paired semitendinosus tendon. Experimental results of a new fixation method].

PROBLEM: The major problem of reconstructing the anterior cruciate ligament (ACL) with the semitendinosus tendon (STT) is the low primary stability of the STT graft fixation techniques. METHODS: On 10 cadaver knees a surgical procedure for arthroscopic reconstruction of the ACL with the double looped STT was performed. The femoral attachment was achieved with an "U-formed" tendon wrapped around a bone-plug, which then was blocked in a single-staged femoral bone tunnel. The tibial fixation was attained using a bone-plug and an interference-screw. Anatomic studies were performed on the STT of the cadaver knees. Isometrical determinations were performed intraoperatively for precise anatomical placement of the tendon. We compared these measurements with the postoperative position of the STT-transplant. The tibial and the femoral attachment was tested separately for primary stability and stiffness. The mode of failure of the fixation methods was determined. RESULTS: The average length of the STT was 29.4 cm (SD +/- 3.6 cm, 24-33). With comparing the measured intraoperative and postoperative isometrical values we found a high correlation. The primary stability of the attaching methods in the pullout-testing amounted for the femoral attachment to 448.2 N (SD +/- 76.5 N, 322-560 N) and for the tibial attachment to 440.0 N (SD +/- 72.5 N, 316-538 N). The average stiffness of the femoral fixation was 29.23 N/mm (SD +/- 1.64 N/mm; 26.6-32.1 N/mm). The average stiffness of the tibial fixation measured 28.31 N/mm (SD +/- 1.55 N/mm, 25.1-30.4 N/mm). CONCLUSION: The presented method provides an economical and easy to perform autologous STT-fixation technique with a high level of primary stability.

Anterior Cruciate Ligament↗