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J M Gavlik

Publications and source records attributed to J M Gavlik.

7 recordsLinked to original sources

[Calcaneus fractures. Open reduction and internal fixation].

AIM OF THIS STUDY: Critical analysis of the medium-term results of open reduction and internal fixation (ORIF) of displaced intra-articular calcaneus fractures with a standardized protocol in a greater patient cohort. METHODS: From October 1993 to December 1999 314 patients (mean age 42.3 years) with 348 calcaneus fractures were seen at the Dresden University Hospital. 41 fractures were open, 4 with 1st degree, 28 with 2nd and 9 with 3rd degree soft tissue damage. 275 displaced intra-articular fractures were treated with ORIF, 262 (95.3 %) with plate osteosynthesis via an extended lateral approach. 169 patients could be evaluated at a mean of 18 months (range 10-47 months) postoperatively with an extended protocol of questionnaire, physical and radiographic examination. RESULTS: The Maryland Foot Score after 18 months follow-up averaged 80.8/100, the mean Zwipp score averaged 146.4/200. The functional result with the Merle d'Aubigné score was judged good to excellent in 86% of cases. Rates of deep infection and superficial wound edge necrosis increased significantly with open fractures and delay in surgery of more than 2 weeks after injury in closed fractures. Clinical results were adversely affected by even minor residual steps in the posterior facet (1-2 mm) as judged by CT or Brodén views (p < 0.001). Böhler's tuberosity-joint-angle had an impact on the final result when falling short compared to the unaffected contralateral side by more than 30% (p < 0.001). CONCLUSIONS: Management of intra-articular calcaneus fractures with a standardized protocol of ORIF and early mobilization leads to reproducible good or excellent clinical results in a majority of patients. New approaches like an interlocking calcaneus plate, the use of subtalar arthroscopy, early soft tissue coverage for complex open injuries and percutaneous screw fixation for selected fractures should further improve prognosis.

Adult↗

Early soft tissue coverage after complex foot trauma.

Complex foot injuries require early and durable soft tissue coverage to reduce infection rates and fibrosis, thereby improving the functional outcome. Definitive wound closure with tissue transfer was achieved as an emergency procedure within 24 hours in 2 of 28 cases, as urgent revision within 72 hours in 9 of 28 cases, and as early revision within 120 hours in 15 of 28 patients. To evaluate the global foot function the Maryland Foot Score was applied to 17 of 28 patients at the 1-year follow-up. The mean score was 74.2 (of 100) points, indicating "good" to "sufficient" foot function. The outcome was superior compared with a series of 18 consecutive open calcaneus fractures with delayed soft tissue coverage (64.4 points). These results were confirmed with a modified Merle d'Aubigné Score. The overall infection rate could be lowered to 7.1% after complex foot injuries with early soft tissue coverage compared to 26 open calcaneus fractures (19.2%). Functional scores allow a reasonable overall assessment of the results, but they are centered on subjective criteria. Thus they must be viewed in conjunction with radiologic and biometric factors as well as criteria valuable for plastic reconstruction, such as two-point discrimination and durability. Unfortunately, emergency flap procedures are still rare in foot surgery, although they permit primary stable osteosynthesis even with complex foot trauma. The foot should gain the same functional rank as the hand with respect to acute or emergency flap procedures to avoid further complications.

Adolescent↗

Expression of the urokinase-type plasminogen activator receptor in human articular chondrocytes: association with caveolin and beta 1-integrin.

The urokinase-type plasminogen activator (uPA) in concert with other proteolytic enzymes plays a critical role in cartilage degradation during osteoarthritis. Urokinase receptor (uPAR), a glycosyl-phosphatidylinositol-linked glycoprotein present on the cell surface of various cell types such as cancer cells, fibroblasts, synoviocytes, and chondrocytes, is a key regulator of the plasmin-mediated pericellular proteolysis. Recently, in arthritic synovial tissue increased uPAR expression has been detected. By immunohistochemical analysis we observed, in addition, enhanced expression of uPAR in chondrocytes of arthritic samples of human cartilage compared to non-arthritic controls. Using in vitro cultured human chondrocytes, we analyzed whether uPAR is associated with structural proteins, which are known to be involved in cell signaling and activation. uPAR in phorbol-12-myristate-13-acetate-stimulated chondrocytes colocalized with caveolin as well as beta 1-integrin, as demonstrated by double immunostaining with specific antibodies. Furthermore, uPAR was present in caveolae-like structures of chondrocytes as detected by immunoelectron microscopy. Finally, both caveolin and beta 1-integrin were coprecipitated with uPAR-specific antibodies from cell extracts suggesting that these proteins may form functional complexes in human chondrocytes. The localization of uPAR in caveolae and its close association with caveolin and beta 1-integrin points to a significance of uPAR-mediated signaling pathways in human chondrocytes.

Cartilage, Articular↗

Characterization of caveolins from human knee joint catilage: expression of caveolin-1, -2, and -3 in chondrocytes and association with integrin beta1.

Interactions between the extracellular matrix (ECM) and chondrocytes are of great importance for structure and function of cartilage. The present study was undertaken to answer the question whether caveolins take part in integrin-mediated cell-ECM interactions in the human cartilage. In samples of human knee joint cartilage, we detected the caveolin subtypes -1, -2, and -3 by immunohistochemical methods. Double-label experiments revealed a colocalization of caveolin with beta1-integrin. Results of immunoprecipitation and immunoblotting assays show that beta1-integrins associate with all three caveolin subtypes in human chondrocytes and indicate that they are part of the same complexes. Furthermore, immunoelectron microscopy shows the localization of beta1-integrin in caveolae-like structures of the cell membrane. The data stimulate further investigations on the role of the caveolin-integrin complex for integrin-mediated signaling pathways in chondrocytes.

Cartilage↗

Avascular necrosis after minimally displaced talus fracture in a child.

This is a case report of a delayed diagnosis in a 5 year old child who sustained a minimally displaced fracture of the proximal or posterior aspect of the talar neck of the left foot with no subluxation at the subtalar or ankle joint of his left talus. Avascular necrosis (AVN) appeared 6 months after the injury. The further course was protracted with another 12 months of non-weight bearing. The case was followed until 36 months after the injury with nearly full functional recovery. An extensive literature review revealed a calculated incidence of AVN after reportedly non-displaced talus fractures in children of 16 per cent which is considerably more than is reported in adults. Nearly half of all reported cases occurred after the fracture had been missed initially. 8 of 11 cases with reported age occurred between 1 and 5 years. No child was older than 9 years, which indicates that the immature talus may be more prone to AVN. Some possible causes for the higher incidence of AVN in children with non-displaced talus fractures are discussed. Prolonged non weight-bearing cannot be recommended, since it reportedly does not alter the course of the disease.

Ankle Joint↗

[Complex trauma of the foot].

Following complex foot injuries (incidence up to 52%) in the multiply-injured patient the ultimate goal remains the same as for all significant foot injuries: the restoration of a painless, stable and plantigrade foot to avoid corrective procedures with moderate results. In the case of a complex trauma of the foot (5 point-score)--e.g. a crush injury--primary amputation in the multiply-injured patient (PTS 3-4) is indicated. Limb salvage (PTS 1-2) depends on the intraoperative aspect during the second look (within 24-48 hours after injury): the debridement has to be radical, the selection of amputation level should be at the most distal point compatible with tissue viability and wound healing. A free tissue transfer should be done early if necessary. Single lesions presenting with a compartment syndrome need an immediate dorsal fasciotomy, in the case of a multiply-injured patient as soon as possible. Open fractures are reduced following radical debridement and temporarily stabilized with K-wires and/or tibiotarsal transfixation with an external fixateur until the definitive ORIF. Dislocation-fractures of the talus type 3 and 4 according to Hawkins' classification need open reduction and internal fixation by screws (titan). Open fractures of the calcaneus are stabilized temporarily by a medial external fixateur after debridement until the definitive treatment. If there is a compartment syndrome an immediate dermatofasciotomy is essential. Like closed, calcanear fractures in multiply-injured patients dislocation-fractures of the Chopart's joint need immediate open reduction only if it is an open fracture or associated with a compartment syndrome. The incidence of a compartment syndrome in the case of dislocation fractures of the Lisfranc's joint is high and therefore a dorsal dermatofasciotomy without delay is critical. Open reduction and internal fixation are achieved either by 1.8 mm K-wires or 3.5 mm cortical screws. To avoid further soft tissue damage a delayed primary closure can be necessary and a temporary tibio-tarsal transfixation is useful. Despite the life-threatening injuries of the multiply-injured patient one must insist on an exact diagnosis of the foot trauma (radiographs in 3 standard projections: exact lateral, dorso-plantar, 45 degrees oblique) if long-term disability due to articular incongruities and complex derangement of the arc geometry of the foot is to be avoided.

Amputation, Surgical↗