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A new biological glue for cartilage-cartilage interfaces: tissue transglutaminase
SESSION 5
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Preliminary results with the AO-wrist arthrodesis plate: A complex outcome evaluation
A new biological glue for cartilage-cartilage interfaces: tissue trausglutaminase
M. Sauerbier, B. Bickert, S. Kluge, N. M. Kania, G. G e r m a n n
Bern, Switzerland, *Wisconsin, USA
LudwigshaJ&n, Germany Objectives Although diagnosis and therapeutic options (e.g. limited wrist fusion) for post-traumatic and degenerative wrist arthropathies have improved during the last decade, total wrist fusion is still frequently regarded as the best option for treatment. Negative and positive aspects of a total wrist fusion have to be evaluated with respect to the patient's expectations and needs. A recently introduced AO-plate was used for arthrodesis in this protocol. The purpose of this study was to compare pre- and postoperative hand function and grip strength, pain control, and subjective quality of life. In addition we wanted to evaluate if it is still worth performing this procedure in comparison to the results in the literature on wrist salvage procedures.
Methods Forty-one patients underwent wrist arthrodesis between May 1994 and April 1996 using the recently introduced, prebent AO-plate after earlier wrist trauma. In all cases cancellous bone was used. Thirty-five patients were examined. The average follow-up time was 15 months. Hand function was compared clinically. Grip strength was measured by using a JAMARDynamometer and the Dexter-Computer System. Pain control was evaluated by using a visual analogue scale from 0 to 100. Patient's daily activities and general postoperative quality of life were estimated with the new DASH-score.
Results Active finger motion was full in 80% of the patients. Grip strength was reduced up to 50% compared with the contralateral side. The mean preoperative and postoperative pain scores were 48 vs 15 (non-stress) and 80 vs. 50 (stress). Most patients complained of significantly reduced postoperative quality of life, e.g. genital hygiene and limited complex hand functions. In five cases operative revisions were necessary for technical reasons. Four AO-plates had to be removed.
Conclusions Total wrist fusion leads to reduced pain in most patients. Functional deficits require adaptation in daily activities. However, results in this procedure do not encourage wrist fusion as a primary choice if other treatment (e.g. limited wrist fusion) is possible. In comparison with the preoperative situation most patie~ats feel slightly more comfortable. Therefore, wrist fusion should still be considered as a valuable treatment option if diagnosis, indication, goals and the patient's personal profile are properly assessed. Advantages of the new AO-plate method are the perfect adaptation to the anatomy of the carpus, and no need for a corticocancellous strut. Simple cancellous bone chips from the iliac crest or distal radius are sufficient in combination with this type of osteosynthesis, reducing trauma to the donor site.
K. Jiirgensen, D. Aeschlimann*, E. B. Hunziker Current treatment of cartilage fractures is often hampered by the failure of this tissue to adhere spontaneously. Stabilization of fragments with screws and Kirschner wires requires repeated surgical intervention, but even so, stable fixation is frequently not achieved. Biological fibrin adhesives have been used in the repair of chondral and osteochondral defects in orthopaedic and hand surgery with varying success, due to their insufficient adhesive strength. We propose tissue transglutaminase (tTG) as a novel biological glue for cartilage tissue, tTG belongs to a family of enzymes which catalyse the formation of isopeptide bonds between proteins to yield network-like polymers. We developed an in vitro system for the quantitative evaluation of potential adhesives for cartilage tissue under defined conditions. Two cartilage-bone cylinders with a diameter of 3.9 mm were prepared from fresh bovine shoulders. In order to obtain a plane, defined cartilage surface, 50% of cartilage thickness was dissected. The cylinders were fixed in a holding device, the surfaces treated with 4 ~tl tTG solution, activated with a solution containing CaCI v and immediately joined. An 80 g weight was applied vertically and the assembly incubated at 37°C. A device for controlled application of shear forces to the glued cartilage-cartilage interface was developed. A controlled, linear ramped shear force (measured with a load cell; precision: 1.0 × 10-3 N) was applied to the top cylinder transversely to the glued cartilage-cartilage interface until failure occurred. The shear force at failure was taken as a measure of the adhesive strength. The adhesive strength of tTG was compared to that of a commercially available fibrin glue (Tissucol©, Immuno). The adhesive strength of tTG was found to increase approximately linearily within the concentration range 0.252.75 mg/ml. The effect of 1 mg/ml only was comparable to that achieved with Tissucol©, a commercially available fibrin glue employed at a protein concentration of ~ 100 mg/mt. The maximal adhesive strength established after I0 min incubation period was 0.43 + 0.13 NIl2 mm 2 (2.75 mg enzymelml), tTG mediated adhesive strength further increased with time (up to 0.61 + 0.15 NIl2 mm 2 after 30 rain, 1.0 mg enzyme/ml) Pretreatment of cartilage surfaces with chondroitinase AC (to cleave glycosaminogtycan chains of proteoglycans in order to improve availability of protein substrates within the tissue matrix) significantly enhanced tTG-mediated adhesivity. Adhesive strength of tTG remained stable with increasing incubation humidity, whereas that of Tissucol© decreased under the latter conditions. Topographical origin of cartilagebone cylinders within the shoulder joint had no influence on the adhesive strength of tTG or Tissucol©. tTG is a new biological glue which may be of particular value for fixation purposes at cartilage-cartilage interfaces. Our results demonstrate the capacity of tTG to form stable cross-links between cartilage surfaces without the need for proteolytic activation. This may be an advantage compared to
24
commercial fibrin glues, since proteases (i.e. Thrombin) could disturb cartilage integrity. When tTG is applied in conjunction with controlled removal of superficial glycosaminoglycans from cartilage surfaces, the adhesive strength is further improved, tTG is also less sensitive to humidity and temperature variation during and following application. These promising in vitro results indicate that tTG could offer new perspectives for further improving the treatment of patients with chondral defects, i.e. fixation of cartilage fragments, transplant materials, biomatrices or chondrocytes. Since tTG occur in normal cartilage, a therapeutic contraindication of tTG glue is unlikely. It is a single protein component which can be easily obtained by recombinant DNA technology, thereby avoiding the risk in the transmission of pathogenic viruses associated with purification of proteins from human tissue, tTG glue thus appears optimally suited for application in cartilage defect repair.
T H E J O U R N A L O F H A N D SURGERY VOL. 22B SUPPLEMENT 1
Conclusions This technique eliminates extensive exposure of the scaphoid, prevents hypertrophic scar formation, and minimizes injury to the blood supply to the scaphoid. It requires some skill, but this technique is safe and produces consistently satisfactory results.
Scaphoid non-union treated with anatomical staple A. Savornin, Esling
Armkes, France Aim of the study The treatment of certain fractures and pseudarthrosis of the scaphoid bone is by bone graft and osteosynthesis. While the principle of the bone graft is not contested the type of osteosynthesis requires consideration.
Material
Closed insertion technique using Herbert screw fixation in acute fractures of the scaphoid G. Inoue, Y. T a m u r a
Nagoya, Japan Objectives Most authors agree that the vast majority of acute scaphoid fractures have good treatment outcomes, with a rate of union of approximately 95%, if they are immobilized properly for long enough. This fracture is common in active young males, many of whom are manual labourers. These patients are significantly disabled when prolonged immobilization is needed to achieve union. Surgical treatment can allow early mobilization of the wrist, and is justified for patients who cannot afford to be out of work for long periods, or those who need early use of the injured hand due to multiple fractures of the extremities. We report a closed insertion technique for the Herbert screw fixation in acute fractures of the scaphoid.
Materials 40 patients were treated by this technique. The indication for this technique was an undisplaced fracture of the waist (type A2), an oblique fracture of the waist (type B1), and a displaced fracture of waist with offset less than 1 mm and/or fracture gap less than 2 mm between the fragments (type B2).
Methods Through a 1 cm incision over the tubercle of the scaphoid, the pilot hole is drilled with a 1.2 mm K-wire in line with the long axis of the scaphoid. The correct position and length of the guidewire is confirmed under an image intensifier in both frontal and sagittal planes. Following drilling and tapping of the pilot hole, The Herbert screw is inserted free-hand. The patients are allowed to use the injured hand immediately after surgery.
Results All 40 patients achieved solid union with satisfactory wrist function. The average time for union was 6 weeks (range, 4--15 weeks). There were no complications.
The basic principle of the anatomical staple is perfect adaptation to the complex and precise anatomy of the scaphoid. The staple controls the flexion, extension and rotation of the fragments. It has various characteristics: precise angles, notched points and shaped extremities to enable application of compression. The distal point is always implanted in the scaphoid tubercle. The device is available is several sizes and is applied using appropriate ancillary equipment. It is positioned on the anterior face of the scaphoid at the edge of the scaphocapitate and scapholunate interosseous ligaments. Precise orientation enables positioning of the staple points in the scaphoid body without piercing the adjacent articular surfaces. Additional immobilization using a palmar splint is applied for 6 weeks.
Methods Since 1987, 78 cases of pseudarthrosis of the carpal scaphoid bone have been treated. 59 patients were followed-up for 9 to 80 months (mean: 22 months). The following were analysed: pain, strength and range of movement of the wrist and radiological result compared with the healthy contralateral side.
Results All the 59 pseudarthrosis cases followed-up showed consolidation in 3 to 12 months except one case which underwent repeat surgery using the same technique and finally showed consolidation. The 15 cases of pseudarthrosis associated with DISI were consolidated and DISI corrected in 12 cases. The six cases of pseudarthrosis associated with radiological condensation were consolidated. Scaphoid height was normalized in 32% of the cases, increased by less than 10% in 50% and decreased by less than 10% in 18%. The overall results were good or very good in 84% of cases.
Discussion DISI and the instability of pseudarthrosis sites appeared to be adverse prognostic factors. The morbidity associated with the technique was relatively low.
Conclusion This anatomical staple, specifically designed for the scaphoid bone, is suitable for all fracture or pseudarthrosis sites in the bone except Schernberg site 1.
23
Preliminary results with the AO-wrist arthrodesis plate: A complex outcome evaluation
A new biological glue for cartilage-cartilage interfaces: tissue trausglutaminase
M. Sauerbier, B. Bickert, S. Kluge, N. M. Kania, G. G e r m a n n
Bern, Switzerland, *Wisconsin, USA
LudwigshaJ&n, Germany Objectives Although diagnosis and therapeutic options (e.g. limited wrist fusion) for post-traumatic and degenerative wrist arthropathies have improved during the last decade, total wrist fusion is still frequently regarded as the best option for treatment. Negative and positive aspects of a total wrist fusion have to be evaluated with respect to the patient's expectations and needs. A recently introduced AO-plate was used for arthrodesis in this protocol. The purpose of this study was to compare pre- and postoperative hand function and grip strength, pain control, and subjective quality of life. In addition we wanted to evaluate if it is still worth performing this procedure in comparison to the results in the literature on wrist salvage procedures.
Methods Forty-one patients underwent wrist arthrodesis between May 1994 and April 1996 using the recently introduced, prebent AO-plate after earlier wrist trauma. In all cases cancellous bone was used. Thirty-five patients were examined. The average follow-up time was 15 months. Hand function was compared clinically. Grip strength was measured by using a JAMARDynamometer and the Dexter-Computer System. Pain control was evaluated by using a visual analogue scale from 0 to 100. Patient's daily activities and general postoperative quality of life were estimated with the new DASH-score.
Results Active finger motion was full in 80% of the patients. Grip strength was reduced up to 50% compared with the contralateral side. The mean preoperative and postoperative pain scores were 48 vs 15 (non-stress) and 80 vs. 50 (stress). Most patients complained of significantly reduced postoperative quality of life, e.g. genital hygiene and limited complex hand functions. In five cases operative revisions were necessary for technical reasons. Four AO-plates had to be removed.
Conclusions Total wrist fusion leads to reduced pain in most patients. Functional deficits require adaptation in daily activities. However, results in this procedure do not encourage wrist fusion as a primary choice if other treatment (e.g. limited wrist fusion) is possible. In comparison with the preoperative situation most patie~ats feel slightly more comfortable. Therefore, wrist fusion should still be considered as a valuable treatment option if diagnosis, indication, goals and the patient's personal profile are properly assessed. Advantages of the new AO-plate method are the perfect adaptation to the anatomy of the carpus, and no need for a corticocancellous strut. Simple cancellous bone chips from the iliac crest or distal radius are sufficient in combination with this type of osteosynthesis, reducing trauma to the donor site.
K. Jiirgensen, D. Aeschlimann*, E. B. Hunziker Current treatment of cartilage fractures is often hampered by the failure of this tissue to adhere spontaneously. Stabilization of fragments with screws and Kirschner wires requires repeated surgical intervention, but even so, stable fixation is frequently not achieved. Biological fibrin adhesives have been used in the repair of chondral and osteochondral defects in orthopaedic and hand surgery with varying success, due to their insufficient adhesive strength. We propose tissue transglutaminase (tTG) as a novel biological glue for cartilage tissue, tTG belongs to a family of enzymes which catalyse the formation of isopeptide bonds between proteins to yield network-like polymers. We developed an in vitro system for the quantitative evaluation of potential adhesives for cartilage tissue under defined conditions. Two cartilage-bone cylinders with a diameter of 3.9 mm were prepared from fresh bovine shoulders. In order to obtain a plane, defined cartilage surface, 50% of cartilage thickness was dissected. The cylinders were fixed in a holding device, the surfaces treated with 4 ~tl tTG solution, activated with a solution containing CaCI v and immediately joined. An 80 g weight was applied vertically and the assembly incubated at 37°C. A device for controlled application of shear forces to the glued cartilage-cartilage interface was developed. A controlled, linear ramped shear force (measured with a load cell; precision: 1.0 × 10-3 N) was applied to the top cylinder transversely to the glued cartilage-cartilage interface until failure occurred. The shear force at failure was taken as a measure of the adhesive strength. The adhesive strength of tTG was compared to that of a commercially available fibrin glue (Tissucol©, Immuno). The adhesive strength of tTG was found to increase approximately linearily within the concentration range 0.252.75 mg/ml. The effect of 1 mg/ml only was comparable to that achieved with Tissucol©, a commercially available fibrin glue employed at a protein concentration of ~ 100 mg/mt. The maximal adhesive strength established after I0 min incubation period was 0.43 + 0.13 NIl2 mm 2 (2.75 mg enzymelml), tTG mediated adhesive strength further increased with time (up to 0.61 + 0.15 NIl2 mm 2 after 30 rain, 1.0 mg enzyme/ml) Pretreatment of cartilage surfaces with chondroitinase AC (to cleave glycosaminogtycan chains of proteoglycans in order to improve availability of protein substrates within the tissue matrix) significantly enhanced tTG-mediated adhesivity. Adhesive strength of tTG remained stable with increasing incubation humidity, whereas that of Tissucol© decreased under the latter conditions. Topographical origin of cartilagebone cylinders within the shoulder joint had no influence on the adhesive strength of tTG or Tissucol©. tTG is a new biological glue which may be of particular value for fixation purposes at cartilage-cartilage interfaces. Our results demonstrate the capacity of tTG to form stable cross-links between cartilage surfaces without the need for proteolytic activation. This may be an advantage compared to
24
commercial fibrin glues, since proteases (i.e. Thrombin) could disturb cartilage integrity. When tTG is applied in conjunction with controlled removal of superficial glycosaminoglycans from cartilage surfaces, the adhesive strength is further improved, tTG is also less sensitive to humidity and temperature variation during and following application. These promising in vitro results indicate that tTG could offer new perspectives for further improving the treatment of patients with chondral defects, i.e. fixation of cartilage fragments, transplant materials, biomatrices or chondrocytes. Since tTG occur in normal cartilage, a therapeutic contraindication of tTG glue is unlikely. It is a single protein component which can be easily obtained by recombinant DNA technology, thereby avoiding the risk in the transmission of pathogenic viruses associated with purification of proteins from human tissue, tTG glue thus appears optimally suited for application in cartilage defect repair.
T H E J O U R N A L O F H A N D SURGERY VOL. 22B SUPPLEMENT 1
Conclusions This technique eliminates extensive exposure of the scaphoid, prevents hypertrophic scar formation, and minimizes injury to the blood supply to the scaphoid. It requires some skill, but this technique is safe and produces consistently satisfactory results.
Scaphoid non-union treated with anatomical staple A. Savornin, Esling
Armkes, France Aim of the study The treatment of certain fractures and pseudarthrosis of the scaphoid bone is by bone graft and osteosynthesis. While the principle of the bone graft is not contested the type of osteosynthesis requires consideration.
Material
Closed insertion technique using Herbert screw fixation in acute fractures of the scaphoid G. Inoue, Y. T a m u r a
Nagoya, Japan Objectives Most authors agree that the vast majority of acute scaphoid fractures have good treatment outcomes, with a rate of union of approximately 95%, if they are immobilized properly for long enough. This fracture is common in active young males, many of whom are manual labourers. These patients are significantly disabled when prolonged immobilization is needed to achieve union. Surgical treatment can allow early mobilization of the wrist, and is justified for patients who cannot afford to be out of work for long periods, or those who need early use of the injured hand due to multiple fractures of the extremities. We report a closed insertion technique for the Herbert screw fixation in acute fractures of the scaphoid.
Materials 40 patients were treated by this technique. The indication for this technique was an undisplaced fracture of the waist (type A2), an oblique fracture of the waist (type B1), and a displaced fracture of waist with offset less than 1 mm and/or fracture gap less than 2 mm between the fragments (type B2).
Methods Through a 1 cm incision over the tubercle of the scaphoid, the pilot hole is drilled with a 1.2 mm K-wire in line with the long axis of the scaphoid. The correct position and length of the guidewire is confirmed under an image intensifier in both frontal and sagittal planes. Following drilling and tapping of the pilot hole, The Herbert screw is inserted free-hand. The patients are allowed to use the injured hand immediately after surgery.
Results All 40 patients achieved solid union with satisfactory wrist function. The average time for union was 6 weeks (range, 4--15 weeks). There were no complications.
The basic principle of the anatomical staple is perfect adaptation to the complex and precise anatomy of the scaphoid. The staple controls the flexion, extension and rotation of the fragments. It has various characteristics: precise angles, notched points and shaped extremities to enable application of compression. The distal point is always implanted in the scaphoid tubercle. The device is available is several sizes and is applied using appropriate ancillary equipment. It is positioned on the anterior face of the scaphoid at the edge of the scaphocapitate and scapholunate interosseous ligaments. Precise orientation enables positioning of the staple points in the scaphoid body without piercing the adjacent articular surfaces. Additional immobilization using a palmar splint is applied for 6 weeks.
Methods Since 1987, 78 cases of pseudarthrosis of the carpal scaphoid bone have been treated. 59 patients were followed-up for 9 to 80 months (mean: 22 months). The following were analysed: pain, strength and range of movement of the wrist and radiological result compared with the healthy contralateral side.
Results All the 59 pseudarthrosis cases followed-up showed consolidation in 3 to 12 months except one case which underwent repeat surgery using the same technique and finally showed consolidation. The 15 cases of pseudarthrosis associated with DISI were consolidated and DISI corrected in 12 cases. The six cases of pseudarthrosis associated with radiological condensation were consolidated. Scaphoid height was normalized in 32% of the cases, increased by less than 10% in 50% and decreased by less than 10% in 18%. The overall results were good or very good in 84% of cases.
Discussion DISI and the instability of pseudarthrosis sites appeared to be adverse prognostic factors. The morbidity associated with the technique was relatively low.
Conclusion This anatomical staple, specifically designed for the scaphoid bone, is suitable for all fracture or pseudarthrosis sites in the bone except Schernberg site 1.