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Biomedical subjects

D S Hungerford

Publications and source records attributed to D S Hungerford.

At least 181 records · Page 10Linked to original sources
PubMed1978

Curves of the achondroplastic spine: a new hypothesis.

The profile of the achondroplastic dwarf reflects abnormalities in the shape of the spine, particularly in the lumbosacral area. We hypothesize that these abnormalities and the resultant symptoms are secondary and avoidable rather than heritable and inevitable. Because the heads of achondroplastic children are enlarged (n = 50), loading of the vertical spine is increased. Unusually lax ligaments and misshapen vertebrae predispose the spine to yielding under vertical stress. Children and adults uniformly have hip flexion contractures (n 105); these are hypothesized to be the result of uncorrected lumbosacral lordosis. The volume of the spinal canal, reduced by the spinal stenosis of achondroplasia, is decreased additionally by lordosis; some neurologic deficits of achondroplasia are caused by this abnormal curvature. This hypothesis bears practically on treating this common form of dwarfism.

Achondroplasia↗
PubMed1978

Geometric total knee replacement for treatment of the rheumatoid knee.

The results of fifty-four geometric total knee arthroplasties in forty-four patients with definite or classic rheumatoid arthritis were analyzed twenty-four to sixty-four months after the surgical procedure. There were no operative deaths, no postoperative infections, and no known pulmonary emboli. Three patients required additional operative procedures on the knee: one, a patellectomy for pain one year after arthroplasty; the second, resection of tibial bone and reinsertion of the tibial component to correct a flexion contracture; and the third, replacement of the tibial component because of loosening. The relief of pain and increase in ability to carry out the activities of daily living were dramatic in these patients, who, because of the limitations imposed by their rheumatoid arthritis, applied minimum stress on the prosthetic knees. Postoperatively, the average arc of knee flexion was 104 degrees.

Activities of Daily Living↗
PubMed1976

Ischemic necrosis of bone in systemic lupus erythematosus.

Twenty-three patients with systemic lupus erythematosus (SLE) and ischemic bone necrosis are reported. All patients had received corticosteroids prior to the onset of ischemic necrosis, although one patient had received none for 13 years previously. Nineteen (83%) patients had multiple bone lesions including the femoral heads in 21 (91%) which were bilaterally involved in 15. In addition, humeral heads were affected in seven patients and the tibial plateaus, in three. The most striking feature of this group was the high incidence of Raynaud's phenomemon present in 14 (61%) of the 23 patients. Furthermore, central nervous system involvement was present in 10 (43%) patients, more prominent in those without Raynaud's (67%) than in those with vasospasm (29%). Thus, 20 of the 23 patients, or 87%, evidenced vascular abnormalities either in the form of Raynaud's phenomenon and/or systemic vasculitis. The pathogenesis of ischemic bone necrosis is discussed. In SLE, vasospasm or vasculitis, or both, augmented by corticosteroid therapy, could impede the microcirculation and result in the ischemic lesion.

Adult↗
PubMed1976

Patello-femoral joint mechanics and pathology. 1. Functional anatomy of the patello-femoral joint.

Cadaver knee joints were mounted so that life-like forces of weight-bearing were simulated. The patello-femoral contact areas were defined under load throughout the range of movement by the dye method. During movement from extension to 90 degrees of flexion a band of contact sweeps across the patella from inferior to superior pole, but the odd facet makes no contact. At about 135 degrees of flexion separate medial and lateral contact areas form, the medial one limited to the odd facet. From extension to 90 degrees of flexion the patella holds the quadriceps tendon away from the femur, but in further degrees of flexion an extensive "tendo-femoral" contact area forms. Between 90 degrees and 135 degrees of flexion the patella rotates and the ridge between the medial and odd facets engages the femoral condyle. The odd facet is shown to be a habitual non-contact area and the ridge to be subject to high load, observations which correlate with cartilage lesions described in Part 2 of the paper.

Biomechanical Phenomena↗
PubMed1976

Patello-femoral joint mechanics and pathology. 2. Chondromalacia patellae.

Two distinct lesions affect the articular cartilage of the patella. Surface degeneration occurs particularly on the odd facet; it is age dependent, often present in youth and it becomes more frequent with increasing age. It probably does not occasion patello-femoral pain in youth, but may predispose to degenerative arthritis in that joint in later years and is regarded as a consequence of habitual disuse. The term "basal degeneration" is used to describe a lesion in which there is a fasciculation of collagen in the middle and deep zones of cartilage without, at first, affecting the surface. It was found astride the ridge separating the medial from the odd facet in twenty-three adolescents who had complained of prolonged patello-femoral pain. They were treated by excision of the disc of affected cartilage, with relief of pain in most cases. The pathogenesis of basal degeneration is related to the functional anatomy of the patella.

Adolescent↗
PubMed1975

Spinal deformity in adolescence. Early detection and nonoperative management.

Scoliosis and kyphosis, as diseases, can be prevented by early detection of scoliosis and kyphosis as conditions. Nonoperative management is usually successful when its main aim is the prevention of progression. By the time the condition has reached the point where correction is necessary to produce an acceptable end result, nonoperative methods often fail. Scoliosis and kyphosis are frequently missed on routine school physical examinations because they are not specifically looked for or because the examiners are not aware of the early physical findings. The most efficient and effective way for early detection is through school screening clinics in the 10 to 13 year age group.

Adolescent↗
PubMed1975

Early diagnosis of ischemic necrosis of the femoral head.

Intraosseous pressure in the intertrochanteric region, and response to a five mililiter saline load injected intraosseously were measured in twenty-four hips in twenty patients with ischemic necrosis of the femoral head and nine hips in seven controls. All hips in which subsequent biopsy proved ischemic necrosis of the femoral head showed either intraosseous pressure greater than 30 mmHg, a hypertensive response to the saline load, or both. All controls measure less than 30 mmHg intraosseous pressure and no significant pressure rise to the saline injection. Intramedullary venography in ischemic necrosis of the femoral head revealed poor filling of extraosseous veins, diaphyseal reflux and delayed clearance of dye. These changes were present in all stages of ischemic necrosis of the femoral head including the pre-radiologic stage and constitute the basis for early detection.

Femur Head Necrosis↗
PubMedDate not supplied

The effects of ciprofloxacin on human chondrocytes in cell culture.

Ciprofloxacin is a highly potent antibacterial agent that is used extensively in bone and joint infections. Because of reports of potential chondro-toxicity in animals, the effects of this drug on cells derived from human cartilage were tested in liquid micromass and agarose gel cultures. An inhibition of cell proliferation as indicated by a decrease in [3H]-thymidine uptake and bromodeoxyuridine labeling at ciprofloxacin concentrations of 0.5 and 50 mg/l was found which corresponded to the therapeutic and toxic serum levels. There was no effect on proteoglycan synthesis as indicated by 35SO4 incorporation. Immunocytochemistry showed no changes in morphology or staining patterns for type-I procollagen, type-II collagen, keratan sulfate and unsulfated chondroitin. Because the amount of inhibition of DNA synthesis varied with different ciprofloxacin concentrations, this data suggests that this agent has a differential effect on newly differentiating cells and might be the basis for contraindication in pediatric patients.

Adult↗
PubMedDate not supplied

Implantation of an uncemented total hip prosthesis. Technique and initial results of 100 arthroplasties.

A porous-coated modular total hip system was developed for uncemented implantation in dogs. The operative technique was developed in cadaver bones and live animals. One hundred uncemented total hip arthroplasties were performed in 92 dogs. Results were successful in 98% of the joints during follow-ups of 3 months or more. Complications included three luxations of the prosthetic joint, two fissure fractures of the femoral cortex, and one complete displacement of the acetabular component from its bony bed. Four complications were resolved successfully.

Acetabulum↗
PubMedDate not supplied

Quantitative ingrowth analysis of a porous-coated acetabular component in a canine model.

Histomorphometric analysis of bone ingrowth into a porous-coated acetabular component was evaluated in a canine model. A total of nine prostheses were evaluated, 3 at 6 months, 3 at 12 months, and 3 at 24 months after implantation. All implants were grossly stable at the time of retrieval. The mean percentage of bone ingrowth was 12% at 6 months, 24% at 12 months, and 24% at 24 months. Narrow radiolucent lines noted on microradiographs were more evident at the 6 month time period than at the 12 or 24 month time periods. Bone ingrowth into a porous-coated acetabular component in a weight-bearing model may continue beyond the 6 month time period, and early evaluation of bone ingrowth may underestimate final bone ingrowth.

Acetabulum↗
PubMedDate not supplied

Tennis after total hip arthroplasty.

The purpose of this study was to characterize patients who play tennis after undergoing hip arthroplasty in terms of their functional abilities and degree of satisfaction. A questionnaire was sent to all United States Tennis Association member associations in a tri-state area to identify players who had undergone a hip arthroplasty. The study group had 50 men and 8 women with a mean age of 70 years (range, 47 to 89). Only 14% of the patients' surgeons approved this tennis activity, with 34% of the surgeons recommending only doubles. Three patients required revision surgery after a mean of 8 years. One year after arthroplasty, players played both singles and doubles approximately three times per week. All tennis players were extremely satisfied with their hip arthroplasties and their increased ability to participate in their favorite sport. Because this study was confined to association members, further studies are needed to assess the general effect of tennis on total hip arthroplasty. Until future studies are performed, the authors would recommend that physicians advise caution in tennis activities and to carefully follow their patients yearly to see if osteolysis is occurring prematurely.

Aged↗
PubMedDate not supplied

Evidence of inappropriate application of autologous cartilage transplantation therapy in an uncontrolled environment.

Autologous chondrocyte transplantation is a new procedure developed for the treatment of focal articular cartilage defects of the knee. The exact indications and limitations of this procedure have not yet been completely defined through prospective, randomized studies. The purpose of this study was to examine the indications and contraindications for surgery in consecutive cases initially rejected for reimbursement of surgical expenses by insurance companies, but now on appeal, to assess whether patients referred by the physicians met the procedure criteria. Twenty-four consecutive candidates were referred for adjudication when the recommending orthopaedic surgeon appealed a rejection by a medical reviewer. The factors examined included the number and size of the cartilage lesions, the presence of tricompartmental arthritis, transplantation proposed for patellar lesions, patient age, and sagittal plane deformity. In 23 of 24 cases (96%) the indications for the procedure were not met or specific contraindications were present. In 15 of 24 cases (63%) there were multiple contraindications. The results of this study underscore the importance of controlled, application-limited experience before the release of new procedures for widespread clinical applications. The uncontrolled use of this procedure may negatively skew the overall results for this technique, prejudicing a procedure that may be successful for the correct indications.

Adolescent↗
PubMedDate not supplied

Total joint arthroplasty of the knee.

The total knee experience at a hospital in Baltimore with the Universal Instruments and Total Condylar and Kinematic prostheses in 1978 and 1979, and with the PCA prosthesis with and without cement since 1980, has led to the development of the philosophy that impacts on all aspects of total knee arthroplasty. In most instances, if the patient is a suitable risk for surgery and symptoms are sufficiently disabling to justify knee fusion, the authors would first attempt a total knee arthroplasty regardless of age, weight, or other factors. Technical perfection of alignment and component position are their goals. The vast majority of total knee components can be mechanically fixed rigidly without the addition of methylmethacrylate. In general, clinical examinations (up to four years) suggest that the cementless results were equally as good as the cemented results and did not have a tendency to deteriorate with time.

Adult↗
PubMedDate not supplied

Alcoholism associated ischemic necrosis of the femoral head. Early diagnosis and treatment.

Thirty-eight hips in 26 patients with alcoholism associated ischemic necrosis of the femoral head (INFH) have been evaluated by measurement of intraosseous pressure, (IOP) pressure response to a 5 ml saline load injected intraosseously and intraosseous venography. All stages of INFH were characterized by elevated IOP and/or an increased pressure response to the saline load compared to normal controls. Intraosseous venography in INFH was characterized by poor or absent visualization of the main efferent veins draining the proximal femur, diaphyseal reflux and delayed evacuation of dye from the bone. It has been possible to identify both a preradiologic and even preclinical stage of INFH. Core decompression, the removal of an 11 mm plug of bone from the head and neck of the femur, has been carried out on all hips in the study. All patients had pain prior to surgery. Eight patients in Stage I (preradiologic stage) are symptom free and without radiologic progression at follow-up, average 24 months. Only one of 5 patients in Stage II (no collapse of the femoral head) has shown X-ray progression while all remain asymptomatic. In Stage III (collapse, without acetabular involvement), core decompression offers relief of symptoms but does not appear to prevent further head collapse.

Adult↗
PubMedDate not supplied

Nonconstrained total elbow arthroplasty.

Thirty capitellocondylar unhinged implant arthroplasties were performed on 27 patients during the period from October 1976 through June 1981. The average patient age was 59.4 years, with a preoperative diagnosis of rheumatoid arthritis in 28 elbows and osteoarthritis in two elbows. Follow-up periods averaged 39.9 months (range, 10-62 months). The indication for elbow arthroplasty were intractable pain, joint instability, failed synovectomy, or bilateral limitation of motion. Ranged of motion evaluations showed moderate increases in flexion, pronation and supination after operation, although there was no significant improvement in extension. Ewald functional evaluation scores improved significantly from the mean of eight points prior to operation to the postoperative mean of 85 points. The significant complications occurring were deep wound infections, necessitating removal of the prosthesis (6.6%), and subluxation (13.2%), which responded to conservative treatment by long-arm casting. One patient required reconstruction of the medial collateral ligament for subluxation. Ulnar nerve paresthesia developed in 10% of the patients. One patient required neurolysis and transposition of the nerve for relief of symptoms. The posterolateral approach was adopted to reduce the incidence of ulnar nerve complications.

Adult↗