[Subtalare Screw Arthroereisis for the Treatment of Symptomatic, Flexible Pes Planovalgus]. / Die subtalare Schraubenarthrorise zur Behandlung des symptomatischen, flexiblen Pes planovalgus ­ Ergebnisse und eine aktuelle Literaturübersicht.

BACKGROUND: The purpose of this study was to determine the functional outcomes and radiographic results of the talus-stop screw method as minimally invasive subtalar arthroereisis in pediatric and juvenile flexible flatfoot. MATERIAL AND METHODS: We retrospectively evaluated 73 feet from 41 children using the talus stop-screw method, for the period between 2002 and 2011. The age at time of surgery ranged between nine and 14 years. The radiological assessment included measuring the calcaneal pitch, talar declination, talo-first metatarsal angle (Meary) and calcaneal-first metatarsal angle (Costa-Bartani) in the lateral view. To evaluate talo-navicular alignment in the anteroposterior view, the talo-first metatarsalbase angles were measured. To describe the amount of planovalgus deformity in lateral and anteroposterior view, we determined a tarsometatarsal-index by adding the talo-first metatarsal and talo-first metatarsal base angles. RESULTS: 95% of patients were satisfied or very satisfied with postoperative results for morphology, pain and activity level. 95% of patients exhibited no limitations in daily life or sports activity due to foot pain, fatigue or repetitive distorsion. 96% of patients would undergo the surgery again, if necessary. Full weight bearing could be achieved after a mean time of 8.1 (range, 2 - 21) days. All measured postoperative angles improved significantly, except talar inclination. CONCLUSIONS: The talus-stop screw method as a minimally invasive subtalar arthroereisis is a safe and effective treatment for the flexible pes planovalgus deformity in children and adolescents. It preserves canalis tarsi and its proprioceptive structures. The major complication rate is low and, with a vertically inserted cancellous screw, this is an economic procedure. The TMT-index incorporating both planes in pes planovalgus feet appears to be a more precise method to determine this multiplanar deformity and to evaluate treatment options and results.

Treatment of isolated peroneus longus tears and a review of the literature.

BACKGROUND: Isolated peroneus longus tendon tears are rare and represent a frequently overlooked source of lateral ankle pain and dysfunction. Only few cases of isolated peroneus longus tendon tears have been reported and a common treatment algorithm does not exist. The purpose of this study was to give an overview of the literature and to present our experience of 6 consecutive cases that have been treated successfully by operation and immobilizing cast. METHODS: A comprehensive chart review was performed to compile each patient's age, sex, onset of symptoms, time between first symptoms and diagnosis, surgical findings, surgical treatment, length of follow-up, and outcome. The average patient age was 48 years (range 20-63 years). RESULTS: Acute tears occurred in 4 cases, and 2 patients reported about a chronic onset of symptoms. The cause for acute tears was an acute inversion ankle sprain in all cases. Diagnosis was made after an average of 11 months (range 0.75-24 months). There were 2 complete tears, and other 4 were incomplete. An os peroneum was present in 2 cases. In 5 of 6 cases, the results after surgical treatment were excellent or good after a mean follow-up of 28.6 months (range 12-78 months). CONCLUSION: This study indicates that lateral ankle pain may be due to isolated acute or chronic peroneus longus tendon tears. Thorough clinical and radiological diagnosis is necessary to detect this uncommon injury in time. Patients with acute onset of symptoms and short time between symptoms and diagnosis tend to fare better than the chronic tears and delayed diagnosis. Surgical intervention yields successful and predictable results.

Time course of biological activity in fresh murine osteochondral allografts paralleled to the recipient's immune response.

The use of fresh osteochondral allografts is a popular approach to treat articular cartilage lesions. Immunological reactions of the recipient elicited by the allograft's osseous portion, however, frequently result in their deterioration. So far, little emphasis has been put on describing morphology and biological activity in fresh allografts and paralleling these to the immunological processes triggered in the host. Therefore, in the present study murine neonatal femora, serving as osteochondral grafts, were transplanted as fresh isografts (controls) or allografts (the latter in non- or presensitized mice) and retrieved after 2, 5, 10, and 20 days. It was shown that (1) in isografts active bone cells (osteoblasts, osteoclasts) were present, the bone marrow was repopulated with hematopoietic cells, the diaphysis increased in length, and no specific immunological reaction by the recipient was evoked. (2) Allografts transplanted into nonsensitized hosts initially appeared similar as isografts, but activated T lymphocytes at the transplantation site preceded loss of active bone cells within the graft and development of fibrosis within the marrow cavity. (3) In allografts transplanted into presensitized recipients, severe deterioration of the graft was observed with very few active bone cells, accompanied by an invasion of T lymphocytes and fibrosis in the marrow cavity already in early stages. Similar to vital organ transplantation, the function of cells within osteochondral allografts is severely impaired after being recognized by the immune system. Therefore, emphasis has to be placed on the development of procedures preserving cartilage biology while reducing the antigenicity of the allograft's osseous portion.

[Cheilectomy and Kessel-Bonney procedure for treatment of initial hallux rigidus]. / Die Cheilektomie und Operation nach Kessel-Bonney zur Behandlung des initialen Hallux rigidus.

OBJECTIVE: Joint-preserving procedure for initial osteoarthritis of the first metatarsophalangeal joint for improvement of restricted joint motion and achievement of a harmonic gait. INDICATIONS: Hallux rigidus stage I and II according to Regnauld's classification. CONTRAINDICATIONS: Hallux rigidus Regnauld stage III. General medical contraindications to surgical interventions and anesthesiological procedures. SURGICAL TECHNIQUE: Operation in regional anesthesia (foot block). Tourniquet. Longitudinal skin incision over the dorsal aspect of the first metatarsophalangeal joint. Incision of the joint capsule with protection of the extensor hallucis longus tendon and the dorsal neurovascular bundle. Cheilectomy: removal of osteophytes at the metatarsal head and the base of the proximal phalanx. Resection of the dorsal third of the metatarsal head with an oscillating saw in plantar flexion of the proximal phalanx. Kessel-Bonney procedure: dissection of the proximal phalanx. Incomplete dorsal osteotomy with an oscillating saw at the metaphysis of the proximal phalanx and removal of a dorsal wedge with a base of 2-3 mm. Osteosynthesis with mini-plate or transosseous suture. POSTOPERATIVE MANAGEMENT: Postoperative elevation of the operated foot. Analgesia with nonsteroidal anti-inflammatory drugs. Postoperative shoe for 3-4 weeks. Immediate weight bearing. Mobilization of the metatarsophalangeal joint with an elastic bandage. Taping in extension and elastic forefoot dressing for 3 weeks postoperatively. Clinical and radiologic controls after 6 and 12 weeks. RESULTS: 53 operations on 45 patients were performed. 39 patients (86%; 28 female, eleven male, mean age 43.6 years) were followed up. After a period of 26 months (range: 10-51 months), 32 of 39 patients (82%) were satisfied or very satisfied. The median preoperative range of motion was 12.3 degrees for dorsal extension and 17.1 degrees for plantar flexion. Function had increased to a dorsiflexion of 34.2 degrees and a plantar flexion of 32.8 degrees. All patients returned to a normal walking ability after a mean period of 3.7 weeks. Due to delayed wound healing, one revision was necessary. According to Kitaoka's Forefoot Score, the mean preoperative value of 44.3 (standard deviation [SD]: +/- 16) increased postoperatively to a mean value of 78.9 (SD: +/- 12).

The avascular talus: revascularization in an animal model.

Avascular necrosis of bone such as the talus can lead to collapse and loss of function. To avoid this, early revascularization has been proposed as an important event. Revascularization can occur either by vessel growth directly through the bony surface, or by vessel growth into the periosteum or ligaments with secondary reconnection to the bone. The ability to attract new vessels (angiogenesis) of the bony surface and the connective tissue was compared in an animal model. A talus isograft (all cortical surface, periosteum, and ligaments remaining; n = 11) or a sector of a femoral head isograft (cancellous surface, no connective tissue; n = 12) of adult mice was implanted into dorsal skinfold chambers of mice of the same strain. The implants were observed by intravital microscopy every 12 hours. First indicators of angiogenesis were hemorrhages around the implants (tali: 11 of 11, 72 +/- 12 hours; femoral heads: 6 of 12, 84 +/- 24 hours). Next, a sudden redness of the transplant indicated marrow hemorrhage (tali: 9 of 11 after 84 +/- 36 hours; femoral heads: 10 of 12 after 96 +/- 36 hours). Histology showed clear growth of capillaries into the cancellous surface of the femoral heads and possible growth of capillaries into the ligament stumps (tali). However, there was widespread necrosis of the marrow cells indicating failure of recirculation. A cancellous bony surface as well as the soft tissues attached to the bone provided a stimulus to rapid revascularization of the grafts. This model was able to evaluate differing rates of early partial revascularization for various bone surfaces, which may have implications for studying treatment options for certain fracture dislocations (e.g., in the talus).

Cryopreservation of osteochondral allografts: dimethyl sulfoxide promotes angiogenesis and immune tolerance in mice.

BACKGROUND: Although transplantation of cryopreserved bone allografts has become a routine procedure in orthopaedic surgery, biological and immunological impairment remains an unsolved problem that causes clinical failures. Experimental and clinical evidence has indicated that bone grafts that are revascularized early remain viable and contribute to union at the recipient site. Unprotected cryopreservation, used in most bone banks to reduce graft antigenicity, is associated with complete loss of graft viability, potentially contributing to graft failure. The differences in the survival of various cell types during cryopreservation with use of dimethyl sulfoxide, particularly the increased sensitivity of leukocytes to fast freezing, has resulted in a new approach to modulate immunogenicity. On the basis of this concept, it was proposed that a reduction in the immune response and enhanced revascularization of osteochondral allografts could be achieved by rapid cryopreservation with dimethyl sulfoxide. To test this hypothesis, angiogenesis and immune tolerance were quantified in a murine model with use of intravital microscopy. METHODS: Fresh osteochondral tissue and osteochondral tissue that had been cryopreserved with and without dimethyl sulfoxide was transplanted into dorsal skinfold chambers as isografts and as allografts in presensitized and nonsensitized recipient mice. To quantify angiogenesis, the onset of hemorrhages in the vicinity of the grafts and the revascularization of the grafts were determined by means of intravital fluorescence microscopy. To determine the recipient's intravascular immune response to the grafts, the leukocyte-endothelium interaction was assessed on the twelfth day after transplantation. RESULTS: Nine of nine fresh isografts were revascularized at a mean (and standard deviation) of 57 +/- 33 hours, eight of nine isografts that had been cryopreserved with dimethyl sulfoxide were revascularized at 98 +/- 50 hours, and zero of nine isografts that had been cryopreserved without dimethyl sulfoxide were revascularized. Seven of seven fresh allografts were revascularized at 53 +/- 6 hours, and ten of ten allografts that had been cryopreserved with dimethyl sulfoxide were revascularized at 82 +/- 29 hours. However, signs of revascularization faded in four of the seven fresh allografts whereas reperfusion was maintained in the majority (seven) of the ten grafts frozen in the presence of dimethyl sulfoxide. Similar to the findings associated with unprotected frozen isografts, zero of ten unprotected frozen allografts were revascularized. None of the allografts that had been transplanted into presensitized recipients were revascularized, regardless of whether they had been implanted fresh (nine grafts) or had been implanted after protected (eight grafts) or unprotected (nine grafts) freezing. Quantification of the leukocyte-endothelium interaction revealed a reduction in the intravascular immune response to frozen allografts (both protected and unprotected) compared with fresh allografts. CONCLUSION: Osteochondral allografts that had been pretreated by cryopreservation with dimethyl sulfoxide demonstrated improved angiogenesis induction and enhanced immune tolerance compared with unprotected frozen grafts. A selective reduction in donor passenger leukocytes is the proposed mechanism underlying this phenomenon. CLINICAL RELEVANCE: In the absence of presensitization, cryopreservation with dimethyl sulfoxide appears to reduce the immune response to allografts and to enhance their revascularization; in the presence of presensitization, alternatives to allograft transplantation should be considered since the allografts will be exposed to a deleterious immune response.

Targeting her-2/neu with antirat Neu virosomes for cancer therapy.

HER-2/neu (p185(HER2)) oncogene represents an attractive target for antibody-mediated immunotherapy. The major problem of combining chemotherapy and immunotherapy is the severe side effects that limit the use of doxorubicin (Doxo) as a cytotoxic drug. We have used virosomes (Vir; reconstituted fusion-active viral envelopes) as a new drug delivery system and have shown that Vir are capable of binding and penetrating into tumor cells, delivering cytotoxic drugs. We have additionally demonstrated that conjugating Fab' fragments of an antirat Neu (anti-rNeu) monoclonal antibody to Vir selectively and efficiently inhibits tumor progression of established rNeu-overexpressing breast tumors. Fab'-Doxo-Vir combine the antiproliferative properties of the monoclonal antibody and the cytotoxic effect of Doxo in vivo. Furthermore, Fab'-Doxo-Vir significantly inhibit tumor formation at a tumor load representing metastatic spread. These results indicate that Vir conjugated with an antibody against a tumor antigen are a promising new selective drug delivery system for the treatment of tumors expressing a specific tumor antigen.