Marginal gap distance and cyclic fatigue loading for different all-ceramic endocrowns.

OBJECTIVE: The aim of the study was to evaluate the effect of the fabrication techniques of two types of glass ceramics on the marginal gap distance and the fracture resistance of endocrown restorations after cyclic loading. MATERIALS AND METHODS: Forty extracted mandibular first molars were root canal treated. Decoronation was done for all the endodontically treated teeth 2 mm above the cemento-enamel junction. The teeth were individually fixed vertically into epoxy resin mounting cylinders. All teeth were prepared to receive endocrown restorations. The prepared teeth were randomly divided into four equal groups (n=10) according to the all-ceramic materials and technique used for endocrown construction as follows: Group I (n=10): Pressable lithium disilicate glass ceramics (IPS e-max Press), Group II (n=10): Pressable zirconia-reinforced lithium disilicate glass ceramics (Celtra Press), Group III (n=10): Machinable lithium disilicate glass ceramics (IPS e-max CAD), Group IV (n=10): Machinable zirconia-reinforced lithium disilicate glass ceramics (Celtra Duo). The endocrowns were cemented using dual-cure resin cement. All endocrowns were subjected to fatigue loading. The cycles were repeated 120,000 times to clinically simulate one year chewing condition. Marginal gap distance of all endocrowns was measured directly using a digital microscope with x100 magnification. The load required to failure was recorded in Newton. Data were collected, tabulated, and statistically analyzed. RESULTS: Fracture resistance testing of all-ceramic crowns revealed a statistically significant difference between all different ceramic materials used in this study (p-value <0.001). On the other hand, there was a statistically significant difference between all the four ceramic crowns for the marginal gap distance either before or after fatigue cyclic loading. CONCLUSIONS: After considering the limitation of the current study, the following conclusions were given: endocrowns are considered one of the promising minimally invasive restorations for root canal treated molars. CAD/CAM technology revealed better results than heat press technology regarding the fracture resistance of glass ceramics. Heat Press technology revealed better results than CAD/CAM technology regarding the marginal accuracy of glass ceramics.

Retention of different all ceramic endocrown materials cemented with two different adhesive techniques.

OBJECTIVE: The purpose of this in vitro study was to evaluate the influence of two adhesive techniques on the retentive force of four all ceramic endocrowns. MATERIALS AND METHODS: Forty maxillary first molars of approximately similar size and shape were collected. The teeth were all decoronated 2 mm above the level of proximal cement-enamel junction (CEJ) and were all endodontically treated. The teeth were then randomly divided equally into four groups (10 each) according to all ceramic material used, as follows: Group I (VE) - Ten prepared molars were restored with hybrid ceramic (Vita Enamic); Group II (LU) - Ten prepared molars were restored with resin Nano-ceramic (Lava Ultimate). Group III (CD) - Ten prepared molars were restored with zirconia-reinforced lithium di-silicate ceramic material (Celtra Duo); Group IV (LZ) - Ten prepared molars were restored with zirconia ceramic (Lava Zirconia). Each group was then subdivided into two equal subgroups (n=5) according to the type of cement (adhesive technique) used for cementation. Subgroup A (RX ARC): the endocrowns were cemented with a total-etch adhesive resin cement (RelyX ARC). Subgroup B (RXU): the endocrowns were cemented with self-adhesive resin luting cement (RelyX UniCem). The restorations were designed with an outer cylindrical handle located on buccal and palatal surfaces to provide a mean for the removal of the endocrowns during the pull-out testing. The cemented endocrowns were thermocycled and then removed along the path of insertion using a universal testing machine at 0.5 mm/min. The retentive force was recorded, and the stress of dislodgement was calculated using the surface area of each preparation. RESULTS: The highest mean dislodgement stresses were 64.3 MPa for Group I (VE), whereas there was no statistically significant difference between Group I, II and III and LZ showed the lowest values with significant difference between the other three groups. Regarding the type of cement, there was a statistically significant difference between RelyX ARC (mean=60.09 MPa) and RelyX Unicem (mean=49.73 MPa). CONCLUSIONS: Retention of Vita Enamic, Lava Ultimate, and Celtra Duo are significantly higher than Lava Zirconia.

[Alternative autologous breast reconstruction using the free microvascular gracilis muscle flap with horizontal skin island]. / Die alternative autologe Brustrekonstruktion mit dem queren Grazilislappen.

BACKGROUND: While free TRAM or DIEP flaps are still the most common techniques for autologous breast reconstruction, there are also other flaps which are suitable for patients who are not candidates for a TRAM/DIEP flap. In addition to the S-GAP or I-GAP, the transverse myocutaneous gracilis (TMG) flap is an excellent alternative. The tissue utilised is taken from the medial thigh and inferior gluteal area. PATIENTS AND OPERATIONS: We have performed 37 TMG flap operations on 23 patients since 2007. The indications were breast cancer, asymmetry of the breasts and capsular fibrosis. The average age of our patients was 47 years. Incisions are similar to those of a transverse thigh lift. The flap is nourished by perforators from the gracilis and its proximal dominant pedicle. The landmark ventrally is the greater saphenous vein and midpoint of the inferior gluteal fold on the dorsal side. Its size can go up to 30 x 10 cm. Recipient vessels are the internal thoracic vessels. The donor site is closed primarily. All of our patients are immobilised for 2 days and were instructed to avoid sitting for 2 weeks. RESULTS: 12 patients were reconstructed after breast cancer, 8 patients had a capsular fibrosis and 3 patients had an asymmetry. The follow-up period was 8 months. Mean operating time for unilateral reconstruction is 220 minutes, for bilateral reconstruction 325 minutes. The weight of the flaps varied from 220 to 440 grams. It takes approximately 30 minutes to harvest the flap. There was no flap loss. Some of the patients described a tight feeling on the thighs for 3 weeks. They described a hypaesthesia on the dorsal thighs. There was one delayed wound healing caused by haematoma. CONCLUSION: In our department, the TMG has become the most preferred flap for breast reconstruction besides the TRAM/DIEP. Especially slim patients with small breasts or a history of surgery on the abdominal wall are ideal candidates. The tissue from the medial thigh is very similar to the breast tissue. The constant vascular anatomy makes it easy to harvest the flap. The resulting scar is well hidden in the patients' underwear.

[BIAX total wrist arthroplasty: management and results after 42 patients]. / Die BIAX-Handgelenkprothese: Management und Erfahrungen bei 42 Patienten.

The BIAX total wrist arthroplasty was introduced in 1983 by Cooney, Beckenbaugh and Linscheid in the USA. However the production of this prosthesis was discontinued in 2004 without having developed a follow-up model. Between 2001 and 2003 we have implanted the BIAX prosthesis in 42 cases. In contrast to other studies, our patients had more post-traumatic (n = 19) and degenerative athroses (n = 20), only 3 patients had rheumatoid arthritis of the wrist. Follow-up time was 2.6 (+/- 0.8) years. The patients were 53 (+/- 11) years old. Indication for total wrist arthroplasty was comparable to that for arthrodesis. However, as pain reduction is lower in heavy workers these patients were excluded from arthroplasty implantation. Range of movement was preserved by total arthroplasty or slightly improved. Pain was reduced by 4.5 (+/- 2.3) points from 7.6 (+/- 1.0) to 3.0 (+/- 2.1) using a visual analogue scale with 0 points for no pain and 10 points for severe pain. Patient satisfaction with the operation was 7.7 (+/- 2.2, 1 bad, 10 excellent). 4 patients had a postoperative dislocation. After reposition the joints were permanently stable. In one case a flexion contracture of unknown origin was treated by tendon transfer. In 11 patients the prosthesis had to be removed after 2 (+/- 0.9) years. Four of these patients received an arthrodesis, 7 had a change to the Universal2 prosthesis. The reason for explantation was mainly abrasion of the dorsal polyethylene edge of the proximal socket, resulting in foreign body reaction, synovialitis and loosening of the prostheses in 7 patients and permanent dislocation in 2 patients due to the then flattened socket. These complications led us to abandon the implantation of the BIAX prostheses.

[Correction of finger clubbing in primary hypertrophic osteoarthropathy (Touraine-Solente-Gole syndrome)]. / Korrektur der Trommelschlegelfinger unter ästhetischen Aspekten bei hereditärer hypertropher Osteoarthropathie (Touraine-Solente-Gole-Syndrom).

Finger clubbing can be a single physical finding. In Touraine-Solente-Gole syndrome, the primary form of hypertrophic osteoarthropathy, it is mostly associated with bone pain, hyperhydrosis, pachydermy and wrinkling of the forehead. In other cases, the presence of clubbing is associated with neoplastic, pulmonary, cardiac or other diseases and is then called Bamberger-Pierre-Marie syndrome, the secondary type of hypertrophic osteoarthropathy. The patient's history and careful physical examination, sometimes accompanied by laboratory and imaging studies, leads to the diagnosis. A patient with hereditary hypertrophic osteoarthropathy and its clinical symptoms is presented. Surgical correction of the clubbing fingers is demonstrated in the paper with bilateral resection and shortening of the nail bed, nail matrix and resection of soft tissue. Clubbing fingers are rare, but they might be part of a syndrome or a symptom of other diseases. Reconstructive surgery for aesthetic reasons can be performed.

[Hereditary thrombophilia in free microvascular flaps--a case report]. / Hereditäre Thrombophilie und ihre Bedeutung für die freie mikrovaskuläre Gewebetransplantation anhand einer Falldarstellung.

Hereditary thrombophilia sums up a large number of haemostatic disorders, which cause thrombosis independently to external influences. The main cases of hereditary thrombophilias are the hereditary antithrombin defect, the activated protein C resistance, the hereditary protein C defect, the hereditary protein S defect, the antiphospholipid antibody syndrome, the hyperhomocysteinaemia, the increased factor VIII activity and the prothrombin-G20210A-polymorphism. We present a patient who was amputated in both breasts due to cancer. A bilateral microvascular TRAM-flap was planned as primary reconstruction on one breast and secondary reconstruction on the other breast. However in the operation the flap vessels revealed irreversible thromboses so that the intended reconstruction could not be completed in this operation. Postoperatively, a combined hereditary thrombophilia was diagnosed: heterocygote activated protein C resistance, antiphospholipid antibody syndrome and hyperhomocysteinaemia.

[Surgical treatment of groin soft tissue defects]. / Chirurgische Therapieoptionen bei Weichteildefekten der Leiste.

BACKGROUND: Treatment of groin defects remains challenging due to their location and origin. Such defects commonly result from resection of tumours but can also occur after surgical or medical therapy. MATERIAL AND METHODS: From 2003 to 2005, 11 patients were treated with groin defects following radiation therapy and resection of lymph node metastasis, primary carcinoma, and sarcoma. Seven patients received wound closure with rectus femoris muscle flaps, and three had vertical rectus abdominis muscle flaps. One patient was amputated at the hip, and the defect was covered with dorsally pedicled muscle and skin flaps. RESULTS: All flaps healed primarily. There were no secondary infections or lymphorrhea. CONCLUSION: The flaps described here are well vascularised standard flaps which are easily harvested with no major donor site morbidity. They provide sufficient coverage for the groin, reduce long-term conservative treatment, hospitalisation, and problems such as scar contracture.

[Malignant eccrine poroma]. / Das maligne ekkrine Porom.

INTRODUCTION: Malignant eccrine poroma is a very rare tumour of the sweat glands with high malignancy and presenting with a polymorph clinical and histological picture. CASE REPORT: We describe the case of a 99-year-old patient with a malignant poroma on the buttock. Despite the large size of the tumour, no metastasis was found with standard examination techniques. Radical excision and defect closure with a Limberg flap was performed. RESULT: The healing course was uneventful and without complications. CONCLUSION: The malignant poroma is a tumour of high malignancy which can easily be misdiagnosed because of its different forms of presentation. Radical surgical therapy is the only known effective treatment.

[Patients' satisfaction and social reintegration after breast reconstruction with the DIEP/TRAM flap]. / Brustrekonstruktion mit dem freien Bauchfettlappen (DIEP/TRAM): Patientenzufriedenheit und soziale Reintegration.

The aim of the study was to evaluate social reintegration and patients' perception after breast reconstruction with the free TRAM/DIEP flap. Between 2004 and 2006, 100 patients with an average age of 48 years with breast cancer, capsular contracture and lymphangioma underwent single or second stage autologous tissue transfer. In 7 patients reconstruction was performed on both sides (altogether 107 flaps). The patients were seen for postoperative evaluation and were asked for their personal acceptance after reconstruction. Postoperatively, no instability of the abdominal wall was seen. 3 patients had a total flap loss, in 2 patients a partial loss was evident, 1 had a hematoma, 2 showed successfully treated thrombosis of the flap vein, and 2 patients suffered from wound healing problems at the flap and 4 patients at the abdomen. Aesthetic results concerning natural feeling and breast symmetry were graded as excellent and patients' satisfaction was high.

The pedicled rectus femoris muscle flap for reconstruction of complicated abdominal wall defects.

AIM OF THE STUDY: Large or complicated abdominal wall defects caused by recurrent incisional hernias, infections or tumor resections often require the use of prosthetic mesh, local tissue transposition or even distant muscle flaps for proper reconstruction. Due to the sometimes discouraging results of meshes muscle flaps are an appreciated alternative. We followed up a series of cases to assess the value of the pedicled rectus femoris muscle flap. METHODS: Follow up time ranged from 6 months to 4 years. 12 cases of reconstruction of the abdominal wall using pedicled rectus femoris muscle flaps after tumor resections, recurrent incisional hernias, and infection are presented. Abdominal wall stability was examined clinically. The aesthetic and the functional results were assessed using a standardized questionnaire. The loss of torque in the quadriceps muscle was evaluated using a dynamometer. RESULTS: In all but one patients a stable abdominal wall could be reconstructed. We saw no major complications. The loss of true muscular capacity in the quadriceps muscle of the operated leg was 19% compared to the nonoperated leg, but was tolerated very well. CONCLUSION: The donor site morbidity is moderate. The flap provides an easy and save possibility to reconstruct the abdominal wall. The rectus femoris muscle flap should be considered as an alternative for abdominal wall reconstruction.

Revascularization of tissue-engineered nerve grafts and invasion of macrophages.

Nonneural derived nerve conduits fail to support regeneration over larger gaps due to lacking viable Schwann cells. Thus, tissue engineering of nerves is focusing on implantation of viable Schwann cells into suitable scaffolds. We established grafts made from acellular muscles and veins, respectively, seeded with cultured Schwann cells. As timing of revascularization is crucial to determine Schwann cell survival and depending axonal regeneration we studied establishment of vascular architecture in a rat sciatic nerve model (2-cm gap) after 3, 5, 7, and 10 days postoperatively, using albumin bound Evans blue. Additionally, macrophage recruitment was immunohistochemically assessed. Engineered grafts showed a delayed revascularization, starting between day 5 and 7 in comparison to normal autografts, that revascularized by day 3. Macrophage recruitment in autologous nerve grafts was evident by day 3. The engineered groups revealed no macrophage invasion until day 7. As Schwann cells survive up to 7 days in autologous grafts without blood supply, depending purely on diffusion, establishment of vascular structure between day 5 and 7 is rapid enough to support Schwann cell survival in engineered grafts. As these grafts are lacking Wallerian degeneration delayed macrophage invasion may not impair degeneration-dependent regeneration, but presence of macrophage derived or induced growth factors may be decreased.

Neuroma: a donor-age independent source of human Schwann cells for tissue engineered nerve grafts.

Schwann cells are used in combination with biological matrices as tissue engineered nerve grafts in animal models offering a new therapeutic approach for treatment of lesions of the peripheral nervous system. A high yield of human Schwann cells from adult donors is only achieved by pharmacological stimulation, which should, however, be avoided in clinical therapy. Here, we establish cultures of activated human Schwann cells which were isolated from peripheral nerve neuroma which developed after a median nerve lesion. To allow nerve reconstruction neuroma have to be resected. Such neuroma tissue is virtually predegenerated and shows activation of Schwann cells, implying good adherence and high mitotic activity. This allows, irrespective of donor age, growing within a short time period and without any pharmacological treatment.

In vivo predegeneration of peripheral nerves: an effective technique to obtain activated Schwann cells for nerve conduits.

In vivo predegeneration of peripheral nerves is presented as a convenient and effective method to obtain activated Schwann cells and an enhanced cell yield following in vitro cultivation. The experiments conducted in rats were aimed at clinical use in gaining Schwann cell suspensions for filling artificial conduits in order to bridge peripheral nerve gaps. The rat sciatic nerve used as a model was transected distally to the spinal ganglia. Predegeneration in vivo was allowed to take place for 1, 2, 3 and 4 days and up to 1, 2 and 3 weeks. The nerve was then resected and prepared for cell cultivation. Schwann cells cultivated from the contralateral untreated nerve served as control. Immunostaining for S100, nerve growth factor receptor and the adhesion molecules N-cadherin and L1 was used to characterize the general state of the cultures. Viability was assessed by fluorescein fluorescence staining, and the proliferation index was determined by bromodeoxyuridine-DNA incorporation. The Schwann cells from predegenerated nerves revealed an increased proliferation rate compared to the control, whereas fibroblast contamination was decreased. Best results were obtained 1 week after predegeneration.

Comparison of different biogenic matrices seeded with cultured Schwann cells for bridging peripheral nerve defects.

Tissue-engineering as laboratory based alternative to human autografts and allografts provides "custom made organs" cultured from patient's material. To overcome the limited donor nerve availability different biologic nerve grafts were engineered in a rat sciatic nerve model: cultured isogenic Schwann cells were implanted into acellular autologous matrices: veins, muscles, nerves, and epineurium tubes. Autologous nerve grafts, and the respective biogenic material without Schwann cells served as control. After 6 weeks regeneration was assessed clinically, histologically and morphometrically. The PCR analysis showed that the implanted Schwann cells remain within all the grafts. A good regeneration was noted in the muscle-Schwann cell-group, while regeneration quality in the other groups (with or without Schwann cells) was impaired. The muscle-Schwann cell graft showed a systematic and organized regeneration including a proper orientation of regenerated fibers. All venous and epineurium grafts had a more disorganized regeneration. Seemingly, the lack of endoneural tube like structures in vein grafts lead to impaired regeneration. And, apparently, the beneficial effects of implanted Schwann cells into a large luminal structure can only be demonstrated to a limited extent if endoneural like structures are lacking. A tube offers less area for Schwann cell adhesion and it is more likely to collapse. This underlines the role of the basal lamina, or at least an inner structure acting as scaffold in axonal regeneration. Although the conventional nerve graft remains the gold standard, the implantation of Schwann cells into an acellular muscle provides a biogenic graft with basal lamina tubes as pathway for regenerating axons and the positive effects of Schwann cells producing neurotrophic and neurotropic factors, and thus, supporting axonal regeneration.

Orthotopic and heterotopic lower leg reimplantation. Evaluation of seven patients.

Reimplantation is a well-established procedure in reconstructive surgery. This is especially so after amputation of the upper limb since prostheses provide limited function. In unilateral amputation of the lower leg orthotopic reimplantation is the treatment of choice. With bilateral amputation, in which orthotopic reimplantation is not possible because of the complexity of the trauma, heterotopic reimplantation is an option. We report five patients who received orthotopic and two who received heterotopic reimplantations of the lower leg. We assessed the functional outcomewith reference to cutaneous sensation, mobility, pain, and the cosmetic result. The functional outcome was good, as was the patients' satisfaction. Their mobility, stability, and psychological state were satisfactory. Patients with heterotopic reimplantations preferred the reimplanted leg to a prosthesis. Although reimplantation of the lower leg requires prolonged hospitalisation, delayed mobilisation and secondary operations, we conclude that there is an indication for this operation in order to improve the patient's quality of life.

Tissue engineering of peripheral nerves: A comparison of venous and acellular muscle grafts with cultured Schwann cells.

Bioengineering is considered to be the laboratory-based alternative to human autografts and allografts. It ought to provide "custom-made organs" cultured from patient's material. Venous grafts and acellular muscle grafts support axonal regeneration only to a certain extent because of the lack of viable Schwann cells in the graft. We created a biologic nerve graft in the rat sciatic nerve model by implanting cultured Schwann cells into veins and acellular gracilis muscles, respectively. Autologous nerve grafts and veins and acellular muscle grafts without Schwann cells served as controls. After 6 and 12 weeks, regeneration was assessed clinically, histologically, and morphometrically. The polymerase chain reaction analvsis showed that the implanted Schwann cells remained within all the grafts. The best regeneration was seen in the control; after 12 weeks the number of axons was increased significantly compared with the other grafts. A good regeneration was noted in the muscle-Schwann cell group, whereas regeneration in both of the venous grafts and the muscle grafts without Schwann cells was impaired. The muscle-Schwann cell graft showed a systematic and organized regeneration including a proper orientation of regenerated fibers. The venous grafts with Schwann cells showed less fibrous tissue and disorganization than the veins without Schwann cells, but failed to show an excellent regeneration. This might be attributed to the lack of endoneural-tube-like components serving as scaffold for the sprouting axon. Although the conventional nerve graft remains the gold standard, the implantation of Schwann cells into an acellular muscle provides a biologic graft with basal lamina tubes as pathways for regenerating axons and the positive effects of Schwann cells producing neurotrophic and neurotropic factors, and thus, supporting axonal regeneration.

The effect of the immunosuppressant FK 506 on peripheral nerve regeneration following nerve grafting.

Nerve allografts are highly antigenic and require the continuous use of immunosuppressive drugs. Neurotoxic complications from immunosuppressant therapy with FK 506 have been noted in the central and peripheral nervous system although an increased rate of axonal regeneration has also been noted. Regeneration of peripheral nerve grafts was assessed in a rat model clinically and morphometrically after treatment for 2 and 6 weeks with two different doses of FK 506. Good regeneration was noted in all groups at 6 weeks. A significantly higher axon count was observed in both the FK 506 groups after 2 weeks regeneration compared with controls. This beneficial effect was not evident after 6 weeks of regeneration. Whether this is related to a pruning mechanism or to a down-regulation of regenerative processes in the nerve due to possible neurotoxic effects of FK 506 remains unknown.

[Surgical treatment of axillary hidradenitis suppurativa]. / Die chirurgische Behandlung der axillären Hidradenitis suppurativa.

INTRODUCTION: Hidradenitis suppurativa is a chronic inflammatory disease of the cutis with furuncles, fistulas and abscesses, mostly located in the groin and axillary regions. A conservative treatment can not prevent a recurrence. PATIENTS AND METHODS: We report on 16 patients with axillary hidradenitis suppurativa. The inflammatory region was excised, followed by immediate coverage with a transposition flap according to Limberg. Postoperatively, all patients received antibiotic treatment. After 2 weeks, physiotherapy was begun. RESULTS: All wounds healed primarily. Functional and aesthetic results were very satisfactory. Movement of the shoulder showed no restrictions. There was no major complication. The recurrence rate was low. DISCUSSION: Only radical debridement prevents a recurrence. The therapy of choice is radical excision of the affected region and immediate coverage by a transposition flap. Open granulation or split-skin grafting are inferior compared with a primary closure by transposition flap. Using the Limberg flap the donor site can be closed primarily.

[Heterotopic replantation after bilateral lower leg amputation]. / Heterotope Replantation nach bilateraler Unterschenkelamputation.

INTRODUCTION: Replantation is an established procedure in reconstructive surgery. In a bilateral lower leg amputation attempts should be made to rescue at least one extremity, if the patients' vital conditions are stable. PATIENT AND METHOD: We report on a patient who has suffered a bilateral lower leg amputation. Due to the complex injuries the left leg was heterotopically (cross-over) replanted to the right leg. At the left leg an above knee stump was created. In a second operation a soft tissue defect at the replanted extremity was covered by a free microvascular latissimus dorsi muscle flap. In addition, the tibial nerve was reconstructed. Thirteen months later the patient is able to walk with a prosthesis for his left leg and complete weight bearing of the replanted extremity. DISCUSSION: Indication for replantation depends on accompanying injuries and vital functions of the patient. Compared to a simple amputation a lower leg replantation prolongs hospital stay, delays mobilisation of the patient, and increases the necessary secondary procedures. However, after replantation functional outcome is mostly better than with prosthetic fitting, especially if reconstruction of sensation in the weight-bearing area is successful. Thus, in a bilateral amputation movement and stability, as well as quality of life, are improved by a replanted extremity.

[Therapy of chest wall osteomyelitis]. / Die Therapie der Thoraxwandosteomyelitis.

INTRODUCTION: Chronic osteomyelitis of the chest wall requires radical debridement and defect coverage with well-perfused tissue. The implantation of synthetic material is still under discussion because of the risk of infection. METHODS: A retrospective study was conducted on the complications and functional and aesthetic results of 26 patients with chest wall osteomyelitis after radiation or sternotomy treated by radical debridement and neurovascular pedicled latissimus dorsi muscle. RESULTS: The functional results were excellent with a low complication rate. The muscle showed electric activity synchronous with inspiration and clinically a stabilization of the thoracic defect. DISCUSSION: Maintained muscular activity may play an essential role for stabilizing thoracic defects of up to four ribs or the sternum; implantation of synthetic material is not necessary.