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PubMedDate not supplied

Extraosseous blood supply of the tibia and the effects of different plating techniques: a human cadaveric study.

OBJECTIVE: To describe the extraosseous blood supply of the tibia and how the blood supply of the distal tibia is influenced by different plating techniques. DESIGN: Microdissection of cadaveric adult hip disarticulation specimens following sequential arterial injections of india ink and Ward's Blue Latex was performed. Readily identifiable arterioles measured approximately 0.5 mm in diameter. Their artery of origin was identified, and their position along the medial, lateral, and posterior aspects of the tibia was documented relative to the tibial plafond. Additionally, six matched pairs of limbs were used to assess the effects of different plating techniques on the extraosseous blood supply along the medial aspect of the distal tibia. SETTING: University anatomy laboratory. PATIENTS/PARTICIPANTS: Nine matched pairs ( = 18) of randomly obtained, adult cadaveric hip disarticulation specimens. INTERVENTION: India ink followed by Ward's Blue Latex was injected into the superficial femoral artery at the level of the inguinal crease after cleansing of the arterial system. The skin, subcutaneous tissue, and muscles were dissected from the leg, exposing the arterial system and the extraosseous vessels of the tibia. MEAN OUTCOME MEASUREMENTS: The extraosseous blood supply of each aspect of the tibial diaphysis was determined. Each extraosseous arteriole was identified, and the locations of each documented relative to the tibial plafond. Changes in the filling of these vessels along the medial aspect of the distal tibia were documented in a separate group of specimens ( = 12), which had undergone two different plating techniques. RESULTS: The proximal metaphysis of the tibia was found to have a rich extraosseous blood supply provided primarily from vessels from the popliteal artery, the anterior tibial artery (ATA) laterally, and the posterior tibial artery (PTA) medially. In comparison, the tibial diaphysis was found to have relatively few extraosseous vessels and a considerably hypovascular region, posteriorly. Branches of the ATA were found to supply the posterior aspect of the diaphysis with these branches passing through the interosseous membrane. The diaphysis also received a variable contribution from the PTA. The lateral aspect of the diaphysis was supplied by branches of the ATA. An anastomotic network of arteries from the ATA and PTA formed the rich extraosseous blood supply of the medial distal aspect of the tibia. Open plating of the medial aspect of the distal tibia caused a statistically significant ( < 0.05) greater disruption of the extraosseous blood supply of the metaphyseal region than did percutaneously applied plates. In each specimen, open plating prevented filling of each periosteal vessel in the region as opposed to percutaneous plates, which permitted filling of the extraosseous vessels up to the edge of the plate. CONCLUSIONS: The proximal and distal metaphyseal areas of the tibia have a rich extraosseous blood supply provided primarily by branches of the ATA and the PTA. Open plating of the medial aspect of the distal tibia caused a greater disruption of this extraosseous blood supply than did percutaneously applied plates. Disruption of these extraosseous vessels following fracture and subsequent operative stabilization may slow healing and increase the risk of delayed union and nonunion. These findings support current efforts to develop less invasive methods and implants for operative stabilization of distal tibia fractures.

Adult↗
PubMedDate not supplied

A biomechanical evaluation of methods of distal humerus fracture fixation using locking compression plates versus conventional reconstruction plates.

OBJECTIVES: To examine the biomechanical behavior of 2 techniques of double-plate osteosynthesis for fractures of the adult distal humerus using conventional reconstruction plates and locking compression plates. DESIGN: Basic science study. SETTING: Experimental in vitro study. PATIENTS/PARTICIPANTS: Forty fresh-frozen human distal humeri specimens. INTERVENTION: Four matched groups with 10 humeri each, median age 74 years (46-95), were created using similar bone mineral density values. Two standard configurations of double-plate osteosynthesis (dorsal or 90 degrees configuration) with either conventional reconstruction plates or locking compression plates were studied for biomechanical properties of the constructs. A fracture model with a 5-mm supracondylar osteotomy gap simulating metaphyseal comminution (AO type 13-A3.3) was used. MAIN OUTCOME MEASUREMENT: Stiffness testing of the constructs in anterior/posterior bending, torsion, and axial compression loading. Evaluation of alterations of the bone-implant interface and failure patterns under cyclic loading and strength testing. RESULTS: The study demonstrates that primary stiffness in anterior/posterior bending and torsional loading is significantly increased by using locking compression plates in a 90 degrees configuration (P < 0.05) as compared with dorsally applied plates. The differences between the different plate types are insignificant if applied in the same configuration. It is demonstrated that none of the tested implants failed under cyclic loading within the number of cycles expected for 3 months of use. The bone-implant interface is less likely to fail during strength testing with locking compression plates. CONCLUSION: The biomechanical behavior of the osteosynthesis depends more on plate configuration than plate type. Advantages of locking compression plates are only significant if compared with dorsal plate application techniques. Nevertheless, locking compression plates are helpful supplementary tools for achieving primary stable fracture fixation. This might be of considerable clinical relevance in patients with diminished bone mineral quality or in the presence of metaphyseal comminution.

Aged↗
PubMed2004

Treatment of complex proximal tibia fractures with the less invasive skeletal stabilization system.

OBJECTIVE: Proximal tibia fractures with metaphyseal comminution present a difficult treatment challenge. The Less Invasive Skeletal Stabilization (LISS) internal fixator system has theoretical advantages (minimally invasive fixed angle construct) for the treatment of these injuries. This report presents clinical results of the LISS system for treatment of complex proximal tibia fractures and illustrates the unique properties of the system. DESIGN: Prospective clinical trial. SETTING: Level I trauma center. PATIENTS: Twenty-eight consecutive patients with comminuted proximal tibia metaphyseal fractures (41A3, 41C2, or 41C3) treated with LISS plates. OUTCOME MEASUREMENTS: Healing, fracture alignment, infectious and implant-related complications, and functional outcome based on the Lower Extremity Measure (LEM). RESULTS: Average follow-up was 23 months (range 12-48). Thirty-seven of 38 patients healed their fracture after the index procedure. The other healed after implant removal without the need for further fracture repair. Postoperative fracture alignment was satisfactory in 37 of the 38 cases and was maintained in all patients at union. There were no infectious complications. The average LEM score was 88. CONCLUSIONS: The LISS internal fixator system can be used successfully to treat complex proximal tibia fractures without the need for additional medial stabilization. Surgeons attempting to use fixed angle internal fixation plating systems should familiarize themselves with the significant technical differences between these and traditional plating systems to assure satisfactory results.

Adult↗
PubMed1988

Incomplete fractures associated with penetrating trauma: etiology, appearance, and natural history.

Patient charts and radiographs of 12 patients noted to have an incomplete fracture due to a penetrating injury were reviewed to evaluate the natural history of these fractures. One cortical chip fracture was due to a stab wound; the remainder were due to low-energy handguns. Morphologically, two patterns existed: drill hole fractures through the central metaphyseal region of long tubular bones, and divot fractures of the margins of long bone metaphyses and flat bones. Drill hole fractures and divot fractures complicated by fracture line extension required a weight bearing cast or functional brace while healing. The chip fracture and uncomplicated divot fractures were managed symptomatically. Chip, drill hole, and divot fractures followed a benign course and healed by formation of cortical bone along the defect rim.

Adolescent↗
PubMed1984

Some important epochs in medicine.

One of the problems in attempting to chronicle briefly the great moments in the history of medicine is that, like the healing process itself, turning points are difficult to pinpoint. There have been surprisingly few "eurekas." In addition, unlike the history of corporate bodies or institutions (such as the church and the nation state) there is no continuous record, no deliberate account. However, the lack of such systemic recording has had its advantage in excluding the element of mythology and myopic partisanship. Since we must choose some kind of framework, we have (in addition to the arbitrary division into Ancient, Medieval, Modern Renaissance, and Enlightenment periods) taken a page from the works of August Comte, the eminent 19th Century philosopher, who divided all of history into three states: theologic (fictional), metaphysical (abstract), and scientific (positivistic). The division is convenient because it not only demonstrates the timelessness and transcendence of medicine, but it also makes it obvious that the cyclic nature of medical interests continues, even today, to offer a theologic, metaphysical, and scientific approach to the problems of health care.

Chemistry↗
PubMed1998

Traditional and evidence-based acupuncture: history, mechanisms, and present status.

BACKGROUND: In 1983, the Southern Medical Journal advised its readers that a scientific basis might underlie the popular practice of ancient Chinese acupuncture. Recent studies have proven this to be correct, and a 1997 National Institutes of Health consensus panel recommended acupuncture as a useful clinical procedure. METHODS: Pertinent articles in the literature were reviewed, including our own research. Significantly, we had access to recent important studies from China. RESULTS AND CONCLUSIONS: Most of the 10,000 acupuncturists in the country today practice metaphysically explained "meridian theory" acupuncture using needles to supposedly remove blockages of a hypothesized substance "Qi." Scientific research has shown that healing is not by manipulating Qi but rather by neuroelectric stimulation for the gene expression of neuropeptides. Needles are not necessary. Evidence-based neuroelectric acupuncture requires no metaphysical rituals. It is a simple, useful clinical tool for pain modulation and other conditions and can be easily taught to physicians.

Acupuncture Therapy↗
PubMed1998

Variability of platyspondylic lethal chondrodysplasia: another case report.

We report the radiological and histological findings of another case of platyspondylic lethal chondrodysplasia. The patient was a girl, who died of respiratory failure at 18 days of age. The radiological changes comprised moderate platyspondyly with ovoid-shaped vertebral bodies, broad and short ilia, rhizomelic shortening and mild bowing of the long bones (particularly of the humeri), relatively long short tubular bones, and retarded epiphyseal ossification and ragged metaphyses, which were most similar to those of a mild variant of this entity, the Luton type. However, the histological findings of cartilage, including hypercellularity of the reserve zone with round resting chondrocytes, relatively normal column formation of the proliferative and hypertrophic zones, and incorporation of hypertrophic cartilage with a columnar arrangement into metaphyseal bony trabeculae, resemble those of a severe variant of this entity, the Torrance type. Our observation provides an insight into the phenotypic variabilities of platyspondylic lethal chondrodysplasia.

Fatal Outcome↗
PubMed2001

Rhizomelic spondyloepimetaphyseal dysplasia.

Spondyloepipmetaphyseal dysplasias (SEMDS) are characterized by flattening of the vertebral bodies and epi-metaphyseal involvement of all the tubular bones. We report a 13 year-old boy with a novel variant of SEMD that presents with rhizomelic/mesomelic shortening of the extremities and normal head, hands and feet. Variable metaphyseal involvement and relatively large proximal humeral and knee epiphyses are further distinctive radiographic features in this patient.

Adolescent↗
PubMed1996

Receptors for parathyroid hormone and parathyroid hormone-related peptide: from molecular cloning to definition of diseases.

The parathyroid hormone/parathyroid hormone-related peptide receptor belongs to a distinct family of G protein-coupled receptors, the members of which usually signal through at least two second messenger systems, adenylate cyclase and phospholipase C. The parathyroid hormone/ parathyroid hormone-related peptide receptor is most abundantly expressed in bone, kidney and growth-plate chondrocytes, and, at lower levels, in a variety of fetal and adult tissues. To search for human diseases that are caused by parathyroid hormone/parathyroid hormone-related peptide receptor defects, genomic DNA of patients with pseudohypoparathyroidism type Ib and of patients with Jansen's metaphyseal chondrodysplasia was screened for mutations in all coding exons of the receptor gene. Inactivating parathyroid hormone/parathyroid hormone-related peptide receptor mutations were excluded in patients with pseudohypoparathyroidism type Ib. However, a receptor mutation that causes agonist-independent, constitutive cAMP accumulation was identified in a patient with Jansen's metaphyseal chondrodysplasia, a rare form of short-limbed dwarfism associated with hypercalcemia despite normal or low concentrations of parathyroid hormone and parathyroid hormone-related peptide. These findings allow the conclusion to be drawn that parathyroid hormone/parathyroid hormone-related peptide receptors mediate the endocrine actions of parathyroid hormone, which are required for the control of calcium homeostasis and the autocrine-paracrine actions of parathyroid hormone-related peptide, which are required for normal growth-plate development.

Adult↗
PubMed1992

Growth failure and bony changes induced by deferoxamine.

We reviewed the linear growth and growth plate morphology in all children with homozygous beta thalassemia followed in Toronto, for whom monthly height percentiles were available before, and for a 36-month period after, the initiation of nightly subcutaneous deferoxamine therapy. All patients were less than 7 years of age when begun on deferoxamine, and had received nightly deferoxamine for a minimum of 36 months. Marked abnormalities of the metaphyseal growth plate were readily observed in the distal ulnar, radial, and tibial metaphyses in 11 of 37 patients in whom a significant decline in mean height percentile was also noted. (In 10 of these 11 patients, height was less than the 15th percentile after 36 months.) These 11 patients had received a significantly greater (p less than 0.025) initial and average daily dose of deferoxamine, and had maintained a significantly lower (p less than 0.025) mean serum ferritin concentration over the 36 months, than the remainder of the cohort. To determine whether deferoxamine played a causative role in growth failure, growth in patients who began deferoxamine before the age 2 years was compared to that of patients who began after age 5 years, for the period between 2 and 5 years of age. Only patients begun on deferoxamine prior to age 2 years demonstrated a significant (p less than 0.01) decline in height percentile by the third year, implicating deferoxamine therapy as the cause of growth failure. We conclude that both the decline in height percentile and the bony changes observed in well-chelated patients are directly related to deferoxamine therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗
PubMed2003

Radius decompression for treatment of kienböck disease.

The authors present a new concept in the treatment of Kienböck disease. They believe that the favorable outcome obtained with these different procedures (ie, either shortening of the radius or lengthening of the ulna) is due to the surgical decompression on the distal forearm. The procedure presented is called metaphyseal core decompression and it consists of curettage of the distal radius and ulna (the ulna has been excluded for the past 12 years) through a small cortical window. From 1976 to 2000, 48 patients were operated and retrospectively reviewed. Thirty-five were men and 13 were women, with an average age of 39 years (range, 18-64 years). The dominant limb was involved in 35 patients. All patients complained of pain and had decreased motion of the involved wrist. On radiographic examination, 4 had Lichtman stage 1, 17 had stage 2, and 25 had stage 3A. Patients who had stages 3B or 4 were excluded. Two patients had normal radiographic but MRI diagnostic for Kienböck disease, and were classified as stage 0. There were no postoperative complications reported and no patient had any additional procedure. The long-term follow-up reveals that metaphyseal core decompression produces results at least as good as other surgical procedures, with no postoperative complications.

Journal Article↗
PubMed2004

Intercalary femur and tibia segmental allografts provide an acceptable alternative in reconstructing tumor resections.

Intercalary femur and tibia segmental allografts were implanted in 59 consecutive patients after segmental resection-52 for malignant and seven for benign aggressive bone tumors. The patients were followed up for an average of 5 years. Allograft survival was determined with the Kaplan-Meier method. Infection, fracture, and nonunion rates were determined. The overall 5-year survivorship for the 59 intercalary allografts was 79%, and we found no significant differences between allograft survival in patients receiving or not receiving adjuvant chemotherapy. Infection and fracture rates were 5% and 7% respectively. From 118 host-donor junctions, 11 did not initially heal (9%). The nonunion rate (10 of 69 osteotomies) for diaphyseal junctions was higher than the rate (one of 49 osteotomies) for metaphyseal junctions. Although some patients required reoperations because of allograft complications, it seems that the use of intercalary allograft clearly has a place in the reconstruction of a segmental defect created by the resection of a tumor in the diaphyseal and /or metaphyseal portion of the femur or tibia.

Adolescent↗
PubMed2006

Management of bone loss in revision total knee arthroplasty.

Bone deficiencies around the knee can present a substantial challenge during revision total knee arthroplasty. Bone loss occurs from stress shielding, osteolysis, chronic infection, and bone removed during implant extraction. Smaller defects have traditionally been treated with cement filling or allograft bone chips. Larger defects can be reconstructed with bulk allografts or custom prostheses. A hinged prosthesis may be necessary to account for ligamentous insufficiency. In addition to traditional methods of managing bone loss, recent developments include the use of metaphyseal-filling implants made of highly porous metal. These implants can be press-fit into host bone to accommodate large metaphyseal defects. Each revision knee surgery provides unique challenges, requiring proficiency in multiple techniques of bone loss management.

Arthroplasty, Replacement, Knee↗
PubMed2003

Reduction versus remodeling in pediatric distal forearm fractures: a preliminary cost analysis.

The inherent ability of pediatric metaphyseal radius fractures to heal and remodel made us question the need for immediate anatomic reduction under conscious sedation. We believe that isolated closed distal radius fractures with 15 degrees of angulation and 1 cm of shortening will heal well and remodel completely without clinical or functional sequelae. Time and expense can be decreased by splinting and follow-up without the need for immediate anatomic reduction in the emergency room. In order to answer this question, we retrospectively evaluated 34 pediatric metaphyseal wrist fractures that lost position after attempted reduction and healed in their angulated or shortened position. We looked at the time to healing, time to remodeling and any residual clinical or functional deficits. We then did a comparison cost analysis with time matched patients who had complete but minimally displaced fractures of the distal radius that were treated by immediate splinting with orthopaedic follow-up. Our results showed that skeletally immature patients with open physes, isolated injuries, dorsovolar and radioulnar angulations less than 15 degrees and less than 1 cm of shortening will heal and be out of cast within an average of 6 weeks and completely remodel within an average of 7.5 months. The average time in the emergency room was 2 h less with no reduction. The cost of the emergency room visit with attempted reduction was 50% more than splinting with early referral (US dollars 536 versus US dollars 270). None of our patients had significant clinical deformities or residual functional deficits.

Adolescent↗
PubMed2003

An unusual orthopaedic presentation of acute lymphoblastic leukemia.

A 3-year-old boy of Romanian origin was admitted with the inability to weight bear and pyrexia. He was investigated to rule out septic arthritis. He subsequently developed an atypical clinical picture of fleeting joint arthritis, spiking temperature with poor response to antibiotics and atypical results of investigations. The peripheral blood smear showed a normal leukocyte count, but evidence of blast cells. Bone marrow aspirate confirmed the diagnosis of acute lymphoblastic leukemia. His skeletal radiographic survey had shown evidence of symmetrical metaphyseal sclerosis in the long bones, which has not been previously described as an isolated feature of acute lymphoblastic leukemia. Following a good response to chemotherapy, partial resolution of the sclerosis occurred. This case illustrates that metaphyseal sclerosis can be one of the manifestations of acute lymphoblastic leukemia and delay in diagnosis can easily occur in the absence of classic features of the disease. An early diagnosis is a good prognostic feature of these childhood malignancies.

Child, Preschool↗
PubMedDate not supplied

Hemiepiphysiodesis for posttraumatic tibial valgus.

Posttraumatic tibial valgus is a recognized complication of proximal tibial metaphyseal fractures in children. There is no consensus regarding management of this malalignment; approaches range from repeated osteotomy to therapeutic nihilism. The authors present 12 patients with an average age at fracture of 4 years 11 months, each of whom who was successfully managed by temporary hemiepiphysiodesis. An additional patient (age 33 years) is included to illustrate the potential long-term outcome of "benign neglect."Using staples or, more recently, a 2-hole plate for guided growth, we have demonstrated correction of posttraumatic tibial valgus by all criteria; including mechanical axis deviation, lateral tibial metaphyseal-diaphyseal angle, tibiofemoral angle, and tibial length. We conclude that hemiepiphysiodesis is a safe and effective method of treatment with a high degree of patient/parent satisfaction. There have been no permanent growth arrests.

Bone Plates↗
PubMed2003

Intramedullary pressure increase and increase in cortical temperature during reaming of the femoral medullary cavity: the effect of draining the medullary contents before reaming.

BACKGROUND: Reaming is regarded as the most adverse aspect of the intramedullary nailing procedure since it leads not only to impairment of the vessels but also to an increase in intramedullary pressure and cortical temperatures which may in turn lead to aseptic cortical necroses and pulmonary dysfunction. Intramedullary pressure increase is considered to be the most detrimental of these factors. METHODS: The aim of this study was to investigate the effect on intramedullary pressure and cortical temperature of removing the medullary fat before reaming. The fat was removed through a suction tube inserted proximally. The measurements were made on pairs of human femora whereby in one group the contents of the medulla were drained by suction before reaming. The pressure was measured in the mid diaphysis and in the metaphysis. The temperature was measured in the mid diaphysis. The femora were reamed in a water bath at 37 degrees C and at a constant insertion force. RESULTS: In comparison to the group which was not drained, the pressure for the 9.0 mm reamer in previously drained femora was reduced as follows: positive diaphyseal pressure by 88% (reamer insertion); positive metaphyseal pressure by 78% (reamer insertion); negative diaphyseal pressure by 84% (reamer withdrawal); negative metaphyseal pressure by 65% (reamer withdrawal). No significant difference was determined for temperature increase (median suction, 39.7 degrees C; median without suction, 39.4 degrees C). CONCLUSION: The removal of the medullary contents by suction before inserting reaming instruments leads to a considerable and statistically significant pressure reduction. If the medullary contents are not sucked out before reaming or insertion of unreamed nails, high intramedullary pressure and the risk of embolization is unaltered. Consequently new instruments should be developed to facilitate the removal of the medullary contents before commencing the reaming procedure or insertion of unreamed nails.

Drainage↗
PubMed2000

Long-term results after physiological genu varum.

All reports agree that the physiological genu varum is a normal condition in early childhood which does not require any treatment, but there is no documentation to correlate between the clinical and radiographic severity of the varus deformity in early childhood and the prognosis in later life. Seventy three cases (135 knees) were followed up from the onset of genu varum at age 11.5 months (range, 8-24 months) until the last follow-up, at age 36.5 years (range, 28-65 years). The angles, femorotibial and metaphyseal-diaphyseal of tibia at first examination were analysed on 107 radiographs (57 cases). The femorotibial angle measured 17 degrees (range, 0-40 degrees), and the metaphyseal-diaphyseal angle of the tibia was 8 degrees (range, 0-21 degrees). None of these knees developed Blount's disease. About two-thirds of the cases (50 cases, 89 knees) showed no symptoms at all and were satisfactory, whereas about one-third of the cases (17 cases, 34 knees) reported that sometimes, they have mild pain, stiffness or both, especially on exertion. One can not be sure whether these cases should be interpreted as a beginning of arthrosis or not. More research is needed to study the long-term results after physiological genu varum as unfortunately there appear to be no reports of work on this topic in the world literature.

Adult↗