Outcome of arthroscopic reduction association of the scapholunate joint.

This study evaluates the arthroscopic reduction association scapholunate technique and outcomes. A total of 18 patients with chronic scapholunate instability with mean follow-up of 36 months were reviewed. Postoperatively, the mean visual analogue score was 2.5 and the mean DASH score was 8. The grip strength was 27 kg on the operative side compared with 32 kg on the uninjured side. The mean wrist flexion was 46° and extension was 56°. Seven patients had complications. Six patients had scapholunate joint widening, one had windshield-wipering of the screws with loss of reduction, and two demonstrated progression of scapholunate advanced collapse deformity. Four patients underwent revision surgeries: two revision arthroscopic reduction association scapholunates and two proximal row carpectomies. A preoperative scapholunate gap of greater than 5 mm and the presence of scapholunate advanced collapse Grade I were both predictive of a complication or revision surgery. Patients with a scapholunate gap of greater than 5 mm or scapholunate advanced collapse had statistically higher complications rates.Level of Evidence IV.

Biomechanical comparison of techniques to reduce the bulk of lacerated flexor tendon ends within digital sheaths of the porcine forelimb.

PURPOSE: Zone II flexor tendon repairs may create a bulging effect with increased bulk and resistance to tendon gliding. A biomechanical time 0 study was performed to assess 2 methods of tendon antibulking for work of flexion and strength characteristics. METHODS: We placed 24 fresh-frozen porcine forelimb tendons in a custom jig. Deep flexor tendon was sectioned just distal to the intact A1 and A2 pulleys. Specimens were divided into 3 groups before repair: group 1, nonmodified tendon; group 2, 30 degrees bilateral notch excised from both tendon ends; and group 3, triangular longitudinal central wedge excised from both tendon ends. All repairs used a 4-strand modified Kessler core suture and running circumferential epitendinous suture. Work of flexion, 2-mm gap formation, and ultimate load to failure were tested. RESULTS: Both antibulking techniques (groups 2 and 3) had significantly less work of flexion than group 1 (36.3 and 34.9 J vs 142.9 J, p < .001). There was no significant change in work of flexion between groups 2 and 3 (p > .05). There was no significant difference in terms of 2-mm gap formation among the 3 groups (p > .05). Groups 1 and 3 exhibited a significantly higher load to failure compared with group 2 (p < .05). CONCLUSIONS: The antibulking repair techniques used in this study decrease the work of flexion with no significant change in force to 2-mm gap formation. Group 2, however, did have significantly lower load to failure. These techniques might be beneficial in zone II flexor tendon injury, in which the tight annular pulley system restricts tendon gliding. However, this is a time 0 study and the potential adverse effects of increase tendon manipulation and trauma were not analyzed, which might increase adhesions and scar during the healing phase of tendon repair.

Percutaneous Freehand system intramuscular electrode placement.

The FreeHand (NeuroControl Corporation, USA) system is an implantable electronic neuroprosthesis designed to stimulate muscles of tetraplegic upper limbs to achieve lateral pinch and simple grasp. When first introduced, the system required insertion through multiple large incisions, but recently introduced intramuscular electrodes have allowed the development of a percutaneous electrode placement technique. The technique minimizes incisions, decreases overall operative time and patient morbidity and improves the outcome by minimizing tendon adhesions.

Prevention of fracture healing in rats by an inhibitor of angiogenesis.

Angiogenesis is considered essential to fracture healing, but its role in the healing process remains poorly understood. Angiogenesis inhibitors, which block new blood vessel formation by specifically targeting vascular cells, are currently under development for use in cancer chemotherapy, and are potentially powerful tools for defining the consequences of angiogenic impairment on fracture healing. In this study, we directly tested the effects of the angiogenesis inhibitor TNP-470 on the healing of closed femoral fractures in an established rat model system. Beginning 1 day after fracture, animals received either angiogenesis inhibitor at a therapeutically effective antitumor dose, or a weight-adjusted amount of carrier vehicle. The progress of fracture healing was assessed at weekly intervals for 21 days by radiography and histology; functional assessment was carried out at day 24 by biomechanical testing. By all three criteria, treatment with the angiogenesis inhibitor completely prevented fracture healing. Formation of both callus and periosteal woven bone were suppressed, indicating that both the intramembranous and endochondral pathways of osteogenesis were affected. The resulting tissue resembled "atrophic nonunions" often seen clinically in cases of failed fracture healing, but rarely achieved in animal models. These results show that angiogenesis is essential to very early stages of fracture healing, and suggest this model system may be useful for understanding the mechanisms underlying fracture nonunions due to vascular impairment. Finally, the data raise the possibility that impairment of fracture healing may be an adverse effect of clinical treatments with antiangiogenic drugs.

Ballistics and gunshot wounds: effects on musculoskeletal tissues.

As a result of the increasing number of weapons in this country, as many as 500,000 missile wounds occur annually, resulting in 50,000 deaths, significant morbidity, and striking socioeconomic costs. Wounds are generally classified as low-velocity (less than 2,000 ft/sec) or high-velocity (more than 2,000 ft/sec). However, these terms can be misleading; more important than velocity is the efficiency of energy transfer, which is dependent on the physical characteristics of the projectile, as well as kinetic energy, stability, entrance profile and path traveled through the body, and the biologic characteristics of the tissues injured. Although bullets are not sterilized on discharge, most low-velocity gunshot wounds can be safely treated nonoperatively with local wound care and outpatient management. Typically, associated fractures are treated according to accepted protocols for each area of injury. Treatment of low-velocity, low-energy fractures is generally dictated by the osseous injuries, as these are similar in many regards to closed fractures. Soft tissues play a more critical role in high-velocity and shotgun fractures, which are essentially open injuries. Aside from perioperative prophylaxis, antibiotics are probably required only for grossly contaminated wounds; however, because contamination is not always apparent, most authors still recommend routine prophylaxis. High-energy injuries and grossly contaminated wounds mandate aggressive irrigation and debridement, including a thorough search for foreign material. Open fracture protocols including external fixation or intramedullary nailing and intravenous antibiotic therapy for 48 to 72 hours should be instituted. If there is vascular damage, exploration and repair are best performed after prompt fracture stabilization. Evaluation of the "four Cs"-color, consistency, contractility, and capacity to bleed-provides valuable information regarding the viability of muscle. Skin grafting is preferable when tension is required for wound closure, although other soft-tissue procedures, such as use of local rotation flaps or free tissue transfer, may be necessary, especially for shotgun wounds. Distal neurologic deficit alone is not an indication for exploration, as it often resolves without surgical intervention.

Patterns of strain in the macaque ulna during functional activity.

In vivo bone strain experiments were performed on the ulnae of three female rhesus macaques to test how the bone deforms during locomotion. The null hypothesis was that, in an animal moving its limbs predominantly in sagittal planes, the ulna experiences anteroposterior bending. Three rosette strain gauges were attached around the circumference of the bone slightly distal to midshaft. They permit a complete characterization of the ulna's loading environment. Strains were recorded during walking and galloping activities. Principal strains and strain directions relative to the long axis of the bone were calculated for each gauge site. In all three animals, the lateral cortex experienced higher tensile than compressive principal strains during the stance phase of walking. Compressive strains predominated at the medial cortex of two animals (the gauge on this cortex of the third animal did not function). The posterior cortex was subject to lower strains; the nature of the strain was highly dependent on precise gauge position. The greater principal strains were aligned closely with the long axis of the bone in two animals, whereas they deviated up to 45 degrees from the long axis in the third animal. A gait change from walk to gallop was recorded for one animal. It was not accompanied by an incremental change in strain magnitudes. Strains are at the low end of the range of strain magnitudes recorded for walking gaits of nonprimate mammals. The measured distribution of strains in the rhesus monkey ulna indicates that mediolateral bending, rather than anteroposterior bending, is the predominant loading regime, with the neutral axis of bending running from anterior and slightly medial to posterior and slightly lateral. A variable degree of torsion was superimposed over this bending regime. Ulnar mediolateral bending is apparently caused by a ground reaction force vector that passes medial to the forearm. The macaque ulna is not reinforced in the plane of bending. The lack of buttressing in the loaded plane and the somewhat counterintuitive bending direction recommend caution with regard to conventional interpretations of long bone cross-sectional geometry.

Balloon assisted endoscopic harvest of the latissimus dorsi muscle.

In this study, we present our experience with balloon assisted endoscopic harvest of the latissimus dorsi muscle for extremity reconstruction. The balloon performs most of the dissection under the muscle and creates the optical work space used in the endoscopic dissection. Over the course of this series the operative time has been reduced and averaged 2 hours and 44 minutes. The reconstructive goals were met in all cases. The average axillary incision length was 5.6 cm, and there were an average of 1.3 one-centimeter or smaller counter incisions.

Microvascular techniques in limb-sparing surgery.

Microvascular techniques allowing free tissue transfer have expanded the indications for limb salvage in tumor patients. Preoperative planning should predict the type of deficit anticipated. Specific techniques for soft tissue, skeletal, neurovascular, and composite tissue transfer are discussed. While demanding, the use of living autogenous tissue gives the potential for biologic adaptivity and life-long durability.

Gunshot wounds to the shoulder.

The proximity of vascular, neural, osseous, and muscular structures make gunshot wounds to the shoulder area particularly challenging. This review focuses on the epidemiology, pathophysiology, diagnosis, and treatment of these injuries. Special attention is given to the usefulness of vascular and electrodiagnostic studies.

Case report 819: Periosteal Ewing's sarcoma of the tibia.

An exceptionally rare case of periosteal Ewing's sarcoma involving the mid shaft of the right tibia was reported. In this case, MRI was the technique that confirmed the integrity of the bone marrow. The clinical, radiographic, and histopathologic features of Ewing's sarcoma have been discussed, as has the differential diagnosis of the periosteal type of this tumor.

Case report 810: Giant cell tumor of the first metatarsal.

And unusual case of giant cell tumor in a 3-year-old girl has been presented. The topic of giant cell tumors has been discussed at length. The pathology and the differential diagnosis have been considered. The incidence of giant cell tumors in children and adolescents has also been reviewed and proved to be extremely rare.

The role of microvascular surgery in limb-sparing procedures for malignant tumors of the knee.

Limb-sparing surgery has proven to be a feasible alternative to amputation for treatment of malignant tumors about the knee. Microvascular surgery and the possibility of providing healthy, stable soft-tissue coverage to the affected limb have expanded the possible role of limb-sparing techniques. Microvascular free flaps were utilized in 26 patients undergoing resection for large malignant tumors of the knee or adjacent to the knee. Patients were then followed for a minimum of 3 years to a maximum of 7 years and evaluated for tumor recurrence and limb function. Survival and disease-free interval were 68 and 77 percent, respectively, in stage II patients and only 50 and 0 percent, respectively, in stage III patients. Function, as determined by the MSTS functional evaluation system, was found to be fair to good in all patients. Microvascular free-tissue transfer has proven to be a valuable adjunct in limb-sparing surgery.

The distal radioulnar joint.

A phylogenic review shows the DRUJ to be a highly evolved and specialized structure. The diarthrodial joint, in combination with the TFCC, ligament complex, and oblique fibers of the distal interosseous membrane, permit rotation while preserving stability and transmitting the load borne by the radiocarpal joint to both bones of the forearm. Our improved, yet imperfect, understanding of the anatomy, biomechanics, and pathophysiology of the region, abetted by new imaging modalities and wrist arthroscopy, permit more precise diagnosis and thus more rational treatment. The persistent inconsistency of our results belies our imperfect comprehension. Thus humbled, consider Goethe's admonition as a call to further scrutiny and investigation, "Theory and experience are opposed to each other in constant conflict. Only action can reconcile them."

Hand infections.

The diagnosis and treatment of common hand infections are reviewed. A practical approach to the treatment of these conditions is detailed. This approach emphasizes the anatomic compartments of the hand, the microbiology of infecting organisms, and the patient conditions which modify treatment. Prompt and accurate diagnosis, treatment, and rehabilitation are key for optimal outcome.

A patient registry for orthopedic surgery.

Identification of patient subpopulations for retrospective clinical studies, documentation of residents' clinical experience, and other administrative purposes can be difficult and time consuming. The problem of identification is exacerbated when a teaching program involves several hospitals or when the desired subpopulation is not adequately defined by standard diagnosis or procedure codes used by the institution. A useful patient registry system is reported here for the storage and retrieval of data on orthopedic patients treated by surgical residents at a major teaching hospital and its affiliates. The registry uses a simple, yet powerful encoding scheme to describe patient entries. In addition to a multidimensional encoded description based on SNOMED, the system supports the entry of free text to provide greater detail. This combination gives the patient registry both power and versatility.

The cellular basis of Wolff's law. Transduction of physical stimuli to skeletal adaptation.

The cellular milieu responsible for skeletal homeostasis is extremely complex, comprised of many elements, and serves to accomplish both structural and metabolic responsibilities. From one perspective, it is the interactions of the cells loosely grouped as "osteoregulatory" which must retain many of the mineral and metabolic levels of the body. From another view, the coordinated formation and resorption of mineralized tissues, relegated by this same population of cells, is predominantly responsible for achieving and retaining the structural integrity of the skeleton. Unfortunately, the predominant focus of much research is asympathetic to the multifaceted role of the skeleton; it is perceived either as a mineral reservoir or as a structural entity. The skeleton, however, is both of these things. It is not until we acknowledge the dual responsibility of bone that we will be able to understand what parameters, systemic or local, control its regulation. Considered within the context of a three-dimensional movie, with metabolic roles cast in red and structural ones in green, neither the impact nor depth of the film can be appreciated until viewed through the glasses which consider the intricate balance between both the mechanical and mineral dimensions.