A Modified Osteotomy for Anteromedialization of the Tibial Tubercle.

Tibial tubercle osteotomy is a common treatment option for a number of patellofemoral joint disorders including chondromalacia, "anterior knee pain" syndromes, patellofemoral arthritis, and patellar instability. Tibial tubercle osteotomy can modify tracking and/or patellofemoral contact forces to effect the unloading of chondral defects of the patella or trochlea, correct multiplanar suboptimal alignment, and be used in conjunction with soft-tissue stabilization procedures for instability. The purpose of this Technical Note is to describe, in detail, a modified osteotomy for anteromedialization of the tibial tubercle. The technique combines the concepts of Elmslie-Trillat and Fulkerson and modifies their techniques to produce an osteotomy that decreases lateral patellar pressure and centers the patella correctly in the trochlear groove.

Clinical results after treatment for bidirectional patellar subluxation: Minimum 2-years follow-up.

BACKGROUND: We describe the preliminary clinical results of a patellar stabilization technique to treat bidirectional patellar subluxation (BPS). METHODS: Patients: six patients (one male, five females; mean age 30.2years) underwent this procedure with a minimum of 24months follow-up. Patients were assessed for clinical instability, patellar complications, and need for revision surgery. Patient functional outcomes were evaluated using the criteria of Crosby and Insall and the Kujala Anterior Knee Pain Scale at the time of final follow-up. Patient satisfaction was assessed using a subjective questionnaire. OPERATIVE TECHNIQUE: A semitendinosus tendon autograft is coursed through a transverse tunnel in the distal quadriceps tendon. The medial and lateral aspects of the graft are passed from the quadriceps tendon within subfascial tunnels to the MPFL attachment site and lateral epicondyle, respectively. The graft is fixed in 60° of knee flexion with suture anchors. RESULTS: Surgery for recurrent instability was performed in one case. There were no cases of infection, quadriceps tendon rupture, or patella fracture. At average follow-up of 29.2months (range, 24 to 38months), outcomes were good to excellent in 4/6 of cases. Kujala scores improved significantly from 33.3 (range, three to 58) preoperatively to 70.8 (range, 39 to 96) postoperatively (p<0.05). 5/6 patients reported being satisfied to completely satisfied with their result. CONCLUSION: Patients undergoing bidirectional patellar stabilization with a single tendon graft showed improved postoperative functional scores. The technique is successful in reducing pain and restoring bidirectional patellar stability at 2-years follow-up. LEVEL OF EVIDENCE: IV, retrospective case series.

Medial patellar subluxation: diagnosis and treatment.

Medial patellar subluxation is a poorly recognized clinical condition characterized by chronic anterior knee pain that is exacerbated with knee flexion. Additional symptoms include instability, limited knee motion, and pain with squatting and stair climbing. Full characterization of the patient's knee pain requires an accurate history and physical examination. Diagnosis is typically confirmed during diagnostic arthroscopy. When nonsurgical management (eg, physical rehabilitation, patella-stabilizing bracing) fails, surgery (eg, medial retinacular release, lateral retinacular imbrication, newer techniques to repair or reconstruct the lateral retinaculum/lateral patellofemoral ligament) can lead to good results. Further study is needed to confirm current understanding of medial patellar subluxation and to better define treatment options and prevention strategies.

Preconditioning allows engraftment of mouse and human embryonic lung cells, enabling lung repair in mice.

Repair of injured lungs represents a longstanding therapeutic challenge. We show that human and mouse embryonic lung tissue from the canalicular stage of development (20-22 weeks of gestation for humans, and embryonic day 15-16 (E15-E16) for mouse) are enriched with progenitors residing in distinct niches. On the basis of the marked analogy to progenitor niches in bone marrow (BM), we attempted strategies similar to BM transplantation, employing sublethal radiation to vacate lung progenitor niches and to reduce stem cell competition. Intravenous infusion of a single cell suspension of canalicular lung tissue from GFP-marked mice or human fetal donors into naphthalene-injured and irradiated syngeneic or SCID mice, respectively, induced marked long-term lung chimerism. Donor type structures or 'patches' contained epithelial, mesenchymal and endothelial cells. Transplantation of differentially labeled E16 mouse lung cells indicated that these patches were probably of clonal origin from the donor. Recipients of the single cell suspension transplant exhibited marked improvement in lung compliance and tissue damping reflecting the energy dissipation in the lung tissues. Our study provides proof of concept for lung reconstitution by canalicular-stage human lung cells after preconditioning of the pulmonary niche.

Human soluble tumor-associated antigens promote the suppression of rat mammary tumors by 5-fluorouracil and stimulate the functional activity of immune organs: Experimental and morphological studies.

This study examined whether the soluble 66 and 51 kDa tumor-associated antigens (sTAA) could promote suppression by the anticancer drug 5-fluorouracil (5-Fu) of chemically induced mammary tumorigenesis, and which, if any, morphological changes in the immune organs accompany this treatment. Dimethylbenzanthracene (DMBA, 8 mg/rat, twice) was used to induce mammary tumors. After the appearance of many large tumors, the preparations of sTAA and 5-Fu, alone or in combination, were administered in weekly doses, for 4 weeks. The following groups of mammary tumor-bearing rats were studied: 1) control non treated rats, 2) rats treated with sTAA, 3) rats treated with 5-Fu, 4) rats treated with 5-Fu and sTAA. The experiment was terminated when tumors in 70% of control rats became ulcerous. Treatment with sTAA alone significantly decreased tumor yield and their total area relative to controls. Both of these parameters showed an even larger significant decrease after treatment with 5-Fu, and the most marked decrease was obtained after the combined treatment with 5-Fu and sTAA. Results demonstrated that not only do sTAA have tumor-suppressive properties, they also enhance the anticancer effects of 5-Fu and prevent its toxic side effects. Morphologically, the treatment with sTAA was manifested in a significant increase in the size of the spleen follicles and mantle layer compared to control rats with large tumors. The treatment with 5-Fu decreased the sizes of almost all areas of the spleen compared to control rats, whereas the combined treatment with 5-Fu and sTAA increased all these parameters to the levels found in rats treated with sTAA alone. The total areas of the cortex and paracortex in the lymph nodes increased after treatment with sTAA. Treatment with 5-Fu alone resulted in a significant decrease of these areas which, as seen in the spleen, increased after combined treatment with 5-Fu and sTAA. Similar changes were seen in the areas of the separate lymph node zones. We concluded that the addition of sTAA to conventional tumor chemotherapy regimens has a remarkable synergistic effect on mammary tumors leading to curative antitumor responses of the host's immune organs.

Simultaneous medial and lateral patellofemoral ligament reconstruction for combined medial and lateral patellar subluxation.

Medial patellar subluxation (MPS) is a disabling, often iatrogenic patellar instability due to previous lateral release for patellar instability. Lateral release destabilizes the patella on the lateral side, worsening the initial lateral instability and causing MPS. MPS is poorly recognized and may range from subluxation to true dislocation. This report describes a technique developed in response to episodes of medial and lateral patellar subluxation after failed lateral release for patellar instability. The technique uses a graft that extends from the medial patellofemoral ligament origin through the quadriceps tendon to the lateral epicondyle, thereby reconstructing both the medial and lateral patellofemoral ligaments, as well as providing simultaneous stability to both the medial and lateral sides of the patella.

Medial patellar subluxation without previous lateral release: a case report.

Medial patellar subluxation (MPS) is normally described following a lateral release. We report on a 14-year-old girl with MPS without previous lateral release. Arthroscopic examination demonstrated MPS at 0 and 30° of flexion, and the patella was tight in flexion on the lateral side. A low lateral release with a tibial tubercle transfer was performed, followed by repair of the lateral release with an iliotibial band flap, and lateral patellofemoral ligament reconstruction. Excellent functional outcome was achieved. This type of patellar instability is often overlooked and a high index of suspicion is needed for appropriate diagnosis and treatment.

Lateral Patellofemoral Ligament Reconstruction Using a Quadriceps Tendon Graft.

Medial patellar subluxation (MPS) is normally described after a lateral retinacular release. However, isolated MPS in the absence of a previous lateral release does occur. This type of patellar instability is often overlooked, and a high index of suspicion is needed for appropriate diagnosis and treatment. This report describes a technique developed in response to episodes of isolated MPS. The technique uses a partial-thickness graft from the quadriceps tendon to reconstruct the lateral patellofemoral ligament and provide stability to the lateral side of the patella.

Diagnosis and treatment of lateral patellar compression syndrome.

Chronic anterior knee pain with a stable patella is often associated with overload and increased pressure on the lateral facet due to pathologic lateral soft-tissue restraints. "Lateral pressure in flexion" is a term describing the pathologic process of increasing contact pressure over the lateral patellar facet as knee flexion progresses. This report describes a surgical technique developed in response to lateral pressure in flexion and the shortcomings of traditional arthroscopic lateral release procedures. The technique is performed open with the knee in flexion, and the lateral release is repaired with a rotation flap of iliotibial band to close the defect and prevent patellar subluxation. The technique effectively decreases lateral patellar pressure and centers the patella correctly in the trochlear groove with minimal risk of iatrogenic patellar instability.