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D P Johnson

Publications and source records attributed to D P Johnson.

At least 19 recordsLinked to original sources
PubMed2002

Reconstruction of the lateral patellar retinaculum following lateral release: a case report.

The recognition and treatment of iatrogenic medial subluxation of the patella following lateral retinacular release may be difficult. The diagnosis even by magnetic resonance imaging may be difficult. The use of a medial patellar stabilising brace may be helpful in the diagnosis, alleviating symptoms in the short term and to gain the confidence of the patient. A technique of direct repair that was used successfully is described in a case report.

Adult↗
PubMed2001

The anatomy of the patellar tendon.

The morphology of the attachment of the patellar tendon, its bundle orientation, the differential fascicles length and the position of the apex of the patella were assessed in 22 cadaveric human knees. The patellar apex was 39+/-6% of the width of the tendon from its medial edge. The bulk of tendon was attached to the distal two-thirds of the anterior aspect of the patella. In six cases tendon fibres originated from the posterior surface of the apex of the patella, forming a ridge on the back of tendon. This may represent an anatomical variant accounting for the increased tendon thickness noted on MRI, both incidentally and during assessment for patellar tendonitis. Fascicles were parallel in the sagittal plane but converged in the frontal plane toward their tibial attachment. When bone-patellar tendon-bone (B-PT-B) grafts were harvested, as for anterior cruciate ligament reconstruction, the grafts narrowed distally. When harvesting B-PT-B, the oblique orientation of the fibres in the coronal plane must be borne in mind.

Aged↗
PubMed2001

The outcome of intra-articular debris, following anterior cruciate ligament reconstruction.

Following arthroscopic anterior cruciate ligament reconstruction, radio-opacities were noted on the post-operative radiographs in 40 of 50 consecutive cases. There was no correlation between the presence of these opacities and post-operative knee pain, joint effusion, arthrofibrosis or knee recovery. In 12 cases undergoing a subsequent radiograph between 3 and 18 months post-operatively, opacities were noted in only one case.

Adult↗
PubMed2000

Conservation of the 17-kilodalton antigen gene within the genus Bartonella.

The 17-kDa antigen of Bartonella henselae has previously been shown to elicit a strong humoral immune response in patients with cat scratch disease (CSD) and to be useful in screening human serum samples for CSD. In this study, PCR amplification of genes homologous to the 17-kDa antigen gene of B. henselae was performed using genomic DNAs from several species of Bartonella, including the currently recognized human pathogens. Amplicons of similar size were demonstrated using the following chromosomal DNA templates: B. henselae (two strains), B. quintana (two strains), B. elizabethae, B. clarridgeiae, B. vinsonii subsp. vinsonii, and B. vinsonii subsp. berkhoffii. No evidence of a B. bacilliformis homolog of the 17-kDa antigen gene was obtained using multiple primer pairs. DNA sequencing revealed open reading frames capable of coding for proteins with sizes similar to that of the 17-kDa antigen of B. henselae in all of the amplicons; however, extensive sequence divergence across the genus was noted. Cloning of the amplified products into pUC19 resulted in recombinants that directed synthesis of homologs of the 17-kDa protein. Immunoblot analysis using human sera from CSD cases demonstrated very little cross-reactivity among different species for this protein. In contrast, immunoblots using rabbit serum raised to the recombinant B. henselae antigen showed extensive cross-reactivity with the proteins of other Bartonella species. The data suggest that the use of the 17-kDa antigen as a serologic reagent may allow the development of more specific diagnostic assays. Furthermore, the nucleotide sequences from the various versions of the 17-kDa antigen gene should be useful for rapid identification of Bartonella at the species level.

Amino Acid Sequence↗
PubMed1999

Dermatologic complications in HIV.

The skin is unique in its accessibility for the diagnosis of diseases acquired because of decreased immunity in human immunodeficiency virus (HIV) infection. A majority of HIV-infected patients will have dermatologic problems at some time during their illness. Many of the cutaneous conditions identified will provide the means by which systemic opportunistic infections, neoplasms, and complications of therapy can be identified. The skin provides an opportunity for the recognition of new or foreign conditions as well as exotic manifestations of diseases that complicate HIV infection. A high degree of suspicion and a willingness to examine the entire skin thoroughly and frequently can enable practitioners to reduce the morbidity and mortality associated with HIV infection.

HIV Infections↗
PubMed1996

Aids prevention.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1996

The value of MR imaging in the diagnosis of the os trigonum syndrome.

OBJECTIVE: The objective of this study was to evaluate the value of magnetic resonance (MR) imaging in the diagnosis of the os trigonum syndrome. DESIGN: Sagittal and coronal spin echo MR sequences of the ankle were acquired along with sagittal images in both dorsiflexion and plantar flexion. PATIENTS: Three consecutive patients presenting with posterior triangle pain were assessed. RESULTS AND CONCLUSIONS: MR imaging delineated the anatomical site of the abnormality and demonstrated coexisting pathology in all patients. Flexion/extension MR images yielded additional information regarding the mobility of the os trigonum in one patient. MR imaging is the technique of choice for investigating the os trigonum syndrome.

Adult↗
PubMed1996

Magnetic resonance imaging of patellar tendonitis.

The radiological and MRI appearances of 24 knees with patellar tendonitis resistant to conservative therapy were analysed to identify the characteristic MRI appearance and to determine if the patellar morphology was abnormal. A significant thickening of the tendon was found in all cases; this was a more reliable diagnostic feature than a high signal within the superior posterior and central aspect of the tendon at its proximal attachment. The site of the lesion shown by MRI is more compatible with impingement of the inferior pole of the patella against the patellar tendon than a stress overload of the tendon. There were no significant differences in the length of the patella, inferior pole or length of the articular surface when the patellar morphology was compared with that of a matched control group.

Adult↗
PubMed1993

Symptomatic synovial plicae of the knee.

Forty-five knees (thirty patients) with a specific diagnosis of synovial plica syndrome, and without any other known lesion, were randomized to be treated with either diagnostic arthroscopy alone or arthroscopy and division of all plicae. The diagnosis of synovial plica syndrome had been made on the basis of intermittent pain in the anterior aspect of the knee, painful clicking with activity, giving-way, and a palpable, tender plica. The patients were selected for arthroscopy only if the symptoms had continued unabated after a course of physical therapy. At the time of follow-up, improvement had occurred in only six (29 per cent) of the twenty-one knees in which the plicae had not been divided, in contrast with twenty (83 per cent) of the twenty-four knees in which they had been divided (p < 0.001). Ten (48 per cent) of the knees in which arthroscopic division had not been done were treated with another arthroscopic operation. Seven of these ten knees improved after the subsequent division of the plicae (p < 0.01). We concluded that synovial plicae of the knee may be a definite cause of anterior pain in children and adolescents.

Adolescent↗
PubMed1992

Percutaneous release of the trigger finger: an office procedure.

A new technique for percutaneous release of the trigger finger is described. A 21-gauge hypodermic needle is used to release the A1 pulley. The technique is effective, convenient, safe, and well tolerated by patients. Thirty-three of 35 procedures (94%) led to complete relief of symptoms, and in the remaining two digits partial symptomatic relief was achieved. There were no significant complications. After a mean follow-up of 13 months, there had been no recurrences. This technique should be the treatment of choice for the established trigger finger with symptoms of more than 4 months' duration.

Adult↗
PubMed1992

Lateral patellar release in knee arthroplasty. Effect on wound healing.

A prospective study analyzing the effects of intraoperative lateral patellar release for patellar instability in total condylar knee arthroplasty demonstrated that lateral release was successful in preventing postoperative patellar instability. Division of the superolateral geniculate vessels resulted in an increased incidence of wound discoloration (P < .01) and superficial wound infection (P < .05). Perioperative transcutaneous measurement of the skin oxygen tension demonstrated an objective reduction in lateral wound edge skin viability following lateral release (P < .02). A lower threshold for performing lateral patellar release is necessary. To preserve the viability of the lateral skin edge, lateral release should be performed using the intracapsular approach with preservation of the superolateral geniculate vessels.

Adult↗
PubMed1992

Patellar complications after knee arthroplasty. A prospective study of 56 cases using the Kinematic prosthesis.

A prospective study on 56 knees was performed to analyze the incidence and cause of patellar complications following total knee arthroplasty with the Kinematic prosthesis inserted with the Universal Instrumentation system. Patellar complications occurred in 23 cases: 15 had anterior knee pain. There was 1 case of patellar fracture. Subluxation of the patella occurred in 13 cases, of which 6 were painful. Although the mechanical alignment was correctly reconstructed to neutral in all but 2 cases, the instrumentation tended to allow malpositioning of the components into excessive femoral valgus and compensatory excessive tibial varus that predisposed to patellar subluxation. With this prosthesis and instrumentation, patellar stability is hindered by a very short anterior femoral flange, a shallow patellar groove, and insertion of the components at 3 degrees to the mechanical axis. It should be ensured that the components are correctly positioned, that patellar stability is carefully checked before closing the capsule, and that lateral release is performed more often.

Aged↗
PubMed1992

Beneficial effects of continuous passive motion after total condylar knee arthroplasty.

A randomised, controlled study of the use of postoperative continuous passive motion (CPM) and immobilisation regimen after total condylar knee arthroplasty was performed. CPM resulted in a significant increase in both the early and late range of knee flexion. This increase occurred in both rheumatoid and osteoarthritic patients. The improvement of 10 degrees at 12 months allowed additional important function to be attained. CPM resulted in significantly earlier discharge from hospital. It did not increase the clinical incidence of wound healing problems, nor did it significantly increase the postoperative fixed flexion deformity or the extension lag. CPM can be recommended as a safe and effective modality to achieve more rapid and more successful postoperative rehabilitation after knee arthroplasty.

Adult↗