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D S Johnson

Publications and source records attributed to D S Johnson.

At least 19 recordsLinked to original sources
PubMed2006

The role of preoperative templating in total knee arthroplasty: comparison of three prostheses.

Templating of preoperative radiographs is routinely recommended prior to knee arthroplasty. We performed this study to assess the reproducibility and accuracy of the templates for three commonly used knee implants (PFC, Kinemax, Scorpio). Six lower limb surgeons templated 10 patients for each of the three designs. The inter- and intra-observer reliability and accuracy was calculated. There was marked variation in the reliability of the templating with the tibial insert scoring better than the femoral and the Kinemax being the most reproducible of the three. In general, the intra-observer scores (kappa=0.57-0.81) were better than the inter-observer ones (kappa=0.21-0.60). The Scorpio was the most accurately templated of the three implants, with the percentage correlating with what was actually implanted ranging from 55% to 62% for the femur and 72% to 75% for the tibia, with no templated sizes more than one size different from the actual implant. The other implants ranged from 38% to 42% for the femur and 53% to 58% for the tibia with both having up to 3% more than 1 size difference from the actual implant. We believe that the use of templating in total knee arthroplasty should be interpreted with caution and we urge the development of more accurate prosthesis sizing techniques.

Arthroplasty, Replacement, Knee↗
PubMed2006

Sporting and physical activity following Oxford medial unicompartmental knee arthroplasty.

The purpose of this study was to evaluate and assess the sporting and physical activities of patients who had undergone an Oxford medial unicompartmental knee arthroplasty (UKA). Seventy-six patients who underwent a UKA between 2000 and 2003 were reviewed. Demographic data such as age, sex and comorbidities were recorded. University of California Los Angeles (UCLA) activity level ratings and Oxford knee scores were determined for each patient. The sporting and physical activities of all patients' pre- and post-operatively were recorded. The mean age of patients was 64 years (range 49-81) at surgery and 66 years (range 53-82) at review. The mean follow up time was 18 months (range 4-46). Following surgery there was a significant improvement in UCLA activity level scores from 4.2 to 6.5 (Wilcoxon Matched-pairs Signed-rank Test, p<0.01). Forty-two patients (64%) regularly participated in sport before they became symptomatic with significant knee pain, and thirty-nine patients (59%) regularly participated in sports after surgery. In total 93% of patients successfully returned to their regular sporting and physical activities following surgery. The published long-term survivorship of the Oxford UKA has given surgeons increasing confidence to use the prosthesis on a younger generation of patients. Our study has demonstrated that this population of patients is extremely active. A more detailed study is required to evaluate the long-term effects of sporting activity on the Oxford UKA.

Aged↗
PubMed2006

Re-admission rates within 28 days of total hip replacement.

INTRODUCTION: The aim of the study was to identify the reasons for the higher than expected emergency re-admission to hospital within 28 days of total hip replacement (THR) for Stepping Hill Hospital, Stockport. PATIENTS AND METHODS: Over a 42-month period, 65 (8.5%) of 769 patients were re-admitted within 28 days of discharge following primary THR. Case notes for 61 patients were available for retrospective review to assess premorbidity, initial postoperative complications and reason for re-admission. RESULTS: The main reasons for re-admission were complications related to the procedure. These included thrombo-embolic disease 2.5%, atraumatic dislocation 1.4%, wound complications 1.2% and swollen limb 1.8%. Other causes such as admission to another department for problems not related to THR accounted for 0.8%. CONCLUSIONS: Our findings are comparable with the published literature for early complications following THR. The three main reasons for re-admission were atraumatic dislocation, thrombo-embolic and wound complications such as superficial infection and haematoma are the commonest world-wide. The re-admission rate to hospital within the first 28 days following THR was a clinical indicator suggested by the UK Department of Health. It has subsequently been incorporated in a group of indicators used by the CASPE Healthcare Knowledge Systems (CHKS), a private healthcare consultancy and analysis company, for peer benchmarking. Our re-admission rates are inflated by admissions for non-THR-related reasons. The level of post-THR complications leading to re-admission were acceptable compared with the available published literature regarding 28-day re-admission. We anticipate that this study may act as a benchmark for other trusts.

Adult↗
PubMed2002

The use of knee splints after total knee replacements.

The aim of this randomised prospective study was to establish whether the use of knee splints following total knee replacement is necessary. The study included 81 patients undergoing total knee replacement who were randomised into a 'splint' and a 'no splint' group post-operatively. The following parameters were recorded: The range of movement pre-operatively, 5 days post-operatively and 6 weeks post-operatively; the length of time to straight leg raise; the blood drained from the wound; and the amount of post-operative analgesia required. We found that patients in the 'no splint' group achieved significantly greater flexion at 5 days and 6 weeks post-operatively but drained significantly more blood from the wound. Transfusion requirements were similar in the two groups. There was no other significant difference in the parameters measured between the two groups. In conclusion we found no evidence to advocate the use of knee splints following total knee arthroplasty.

Aged↗
PubMed2001

Direct determination of particle-particle interactions in a 2D plasma dust crystal.

Particle interactions were directly determined from the lateral compression of two-dimensional plasma dust crystals confined in a parabolic potential well. Measured particle separations combined with an equation of state for the crystal were used to derive values for the particle screening length and the charge on the particles. The shape of the parabolic potential well was confirmed by observing trajectories of single particles falling within the well. No evidence of a lateral particle-particle binding was observed.

Journal Article↗
PubMed2001

Outcome measurement in the ACL deficient knee--what's the score?

There is increasing pressure within the United Kingdom for transparent assessment of the performance of every doctor along with the procedures they perform. Unfortunately, the validation of the outcome measures used to assess such procedures has been questioned. This has been well illustrated in the anterior cruciate ligament (ACL) deficient knee. Over 54 different outcome measures used to assess the ACL deficient knee have been identified, few of which were formally assessed at their initial publication. For those most frequently used the Lysholm (I and II) knee scoring scale and Tegner activity score are the only ones to have been adequately validated prior to use. The Cincinnati rating system and International Knee Documentation Committee (IKDC) form were not assessed and the reliability of both measures has since been questioned. Appropriately tested newer measures include the IKDC subjective knee evaluation form, Mohtadi's ACL quality of life outcome measure and the Knee injury and osteoarthritis outcome score (KOOS). We recommend use of the Lysholm II knee scoring scale and Tegner activity score for clinical follow-up of patients and for use as a gold standard to which future measures can be compared. These have their deficiencies and will ultimately require replacement. In view of the international standing of its authors, the IKDC subjective knee evaluation form is likely to be used in preference to the KOOS despite its attractions. For long-term clinical trials the SF-36 should also be used. Further research is required to produce suitable measures for assessing the ACL deficient knee and this work should be appropriately funded.

Anterior Cruciate Ligament↗
PubMed2001

Mucoepidermoid/adenosquamous carcinoma of the skin: presentation of two cases.

BACKGROUND: Mucoepidermoid carcinoma is a relatively common neoplasm of the major and minor salivary glands comprising 10-30% of primary carcinomas. They may involve the skin through direct extension, metastases, and rarely, as a primary focus (adenosquamous carcinoma). OBJECTIVE: To discuss through case reports, the nomenclature, histology, clinical course, and treatment of mucoepidermoid/adenosquamous carcinoma. METHODS: We present a case of mucoepidermoid carcinoma primary to an upper eyelid accessory lacrimal gland with direct cutaneous extension and a case of primary cutaneous adenosquamous carcinoma of the scalp. RESULTS: An eyelid neoplasm of lacrimal origin was initially treated with Mohs micrographic surgery (MMS), requiring an orbital exenteration to achieve a tumor-free plane. In the second case, a primary scalp lesion was cleared with MMS. Neither patient has had local recurrence or metastases. CONCLUSION: Correct diagnosis is crucial to pursuing adequate treatment for this aggressive neoplasm. We support the use of MMS to achieve local control.

Aged↗
PubMed2000

Is tourniquet use necessary for knee arthroscopy?

PURPOSE: With several studies identifying the tourniquet as a factor for increased risk of complications in knee arthroscopy, we wished to identify whether its use is necessary. TYPE OF STUDY: We performed a prospective randomized trial on 109 patients undergoing knee arthroscopy. MATERIALS AND METHODS: All patients had a tourniquet placed on the thigh and were assigned to either have it inflated or not inflated. Personal information, operative details, postoperative pain scores, analgesic requirements, and complications were recorded. RESULTS: The 2 groups were comparable. There was no significant difference between the 2 groups with respect to operative view, duration of operation, pain scores, analgesic requirements, or complications. The tourniquet required intraoperative inflation in 4 patients assigned not to have it inflated; in 1 patient, the tourniquet made no difference to the operative view. CONCLUSIONS: Many orthopaedic units continue to use a tourniquet routinely for knee arthroscopy, probably in the belief that a clear operative view can only be achieved with one. However, the findings in our trial indicate that knee arthroscopy may be performed adequately without the use of a tourniquet. Therefore, we recommend that its routine use for this procedure is discontinued.

Adolescent↗
PubMed2000

Imaging of non-small-cell lung cancer with indium-111 pentetreotide.

PURPOSE: Lung cancer is the leading cause of cancer deaths in the United States. Non-small-cell lung cancer (NSCLC) accounts for 75% to 85% of lung cancers. CT has been the standard anatomic study for localizing and staging NSCLC, although it is associated only with moderate accuracy. In-111 pentetreotide, a radiolabeled somatostatin analog largely used in the scintigraphic localization of neuroendocrine tumors, has been shown incidentally to identify NSCLC lesions. This observation is important in the workup for metastatic disease for neuroendocrine tumors, because presumed metastatic lesions may actually be second primary tumors of NSCLC. In-111 may also serve as a potentially useful adjunct to CT in the anatomic evaluation of NSCLC. The purpose of this study was to determine the likelihood of detecting and localizing NSCLC using In-111 pentetreotide scintigraphy. MATERIALS AND METHODS: Ten patients with known or possible NSCLC were examined using In-111 pentetreotide. Scans were compared with the patients' previously performed chest radiographs and CT scans. RESULTS: In-111 pentetreotide imaging correctly identified sites of tumor involvement as detected by chest CT and surgery in all 10 patients with NSCLC. CONCLUSION: This study demonstrates the uptake of In-111 pentetreotide by NSCLC. This important observation should be considered in the workup for metastatic disease of neuroendocrine tumors with In-111 pentetreotide, because NSCLC can be a source of false-positive findings. In-111 pentetreotide imaging may also serve as a potentially useful adjunct to CT for identifying obscured or equivocal lesions and as an aid in localizing tissue for biopsy.

Aged↗
PubMed2000

Current imaging and possible therapeutic management of glucagonoma tumors: a case report.

Glucagonomas, like other neuroendocrine tumors, express somatostatin receptors in more than 80% of cases. Unfortunately, because of the rarity of these tumors, the sensitivity and specificity of somatostatin analog (octreotide) imaging have not been established. Nonetheless, there have been limited reports in the literature supporting the use of indium In-111 DTPA N-terminal D-phenylalanine (D-PHE1) octreotide for glucagonoma imaging and may be most beneficial as an adjuvant to conventional imaging for tumor staging and therapeutic decision making. Current therapeutic applications of octreotide focus on stabilization of disease in tumors expressing somatostatin receptors, and tumor destruction, using beta-emitting isotopes. In this report, imaging of a glucagonoma with In-111 DTPA-D-PHE1 octreotide scintigraphy is described in a 51-year-old woman examined for a large palpable abdominal mass.

Female↗
PubMed2000

Closure of palatal fistula with a local mucoperiosteal flap lined with buccal mucosal graft.

OBJECTIVE: Oro-nasal fistula is a common complication of palatoplasty. Current methods for fistula repair utilize mucoperiosteal flaps or pedicled flaps. These procedures are often cumbersome and leave a raw nasal surface, which may increase the incidence of postoperative risks and problems. In addition, the recurrence rate of the fistula is as high as 34%. We propose a simple two-layer method of fistula repair to avoid recurrences. DESIGN: A standard mucoperiosteal flap is raised on the oral side. A buccal mucosal graft is harvested from the cheeks and sutured to the nasal side of the flap that is then inset into the fistula. SETTING: Patients were either referred to the senior author's private practice (four patients) or were patients who had previously been operated on by the senior author himself (three patients). SUBJECTS: Study subjects consisted of seven patients, four males and three females, ages 14 months to 8 years. All patients had previously undergone cleft palate repair, complicated by subsequent oro-nasal fistula formation. INTERVENTIONS: All patients underwent oro-nasal fistula repair under general anesthesia with a local mucoperiosteal flap lined with buccal mucosal grafts placed on the nasal side of the flap. RESULTS: In all cases, the fistula was completely closed at first attempt without complications. Patients were followed for a minimum of 2 years, without evidence of recurrence. CONCLUSIONS: Our proposed surgical procedure for fistula closure using a standard mucoperiosteal flap lined with a buccal mucosal graft is a suitable alternative for the repair of postpalatoplasty oro-nasal fistulas. Further study and long-term follow-up is needed to establish this method as a new standard form of repair.

Child↗
PubMed1999

Common peroneal nerve palsy following knee arthroscopy.

We report the case of a 43-year-old woman who underwent knee arthroscopy. Postoperatively, she developed a lesion of the common peroneal nerve, which was confirmed by neurophysiological studies. Exploration showed the nerve to be in continuity and externally undamaged. At review 17 months later, there was incomplete recovery. We believe this lesion was caused by a traction injury related to patient positioning, which has not been reported previously.

Adult↗
PubMed1999

Advanced techniques in liposuction.

Liposuction is a procedure that has been widely used since the 1980s. The introduction of the tumescent technique in 1987 greatly improved the safety of the procedure. Innovative techniques and equip ment modifications have continued to evolve, broadening the scope of application and improving the results that can be obtained. This article discusses several recent advancements in liposuction techniques. Three-Dimensional Tumescent Liposculpture (William R. Cook, Coronado, CA) was developed to view contiguous areas of the body as a unit rather than to simply suction fat from one particular area. Advanced techniques have improved the ability to liposuction difficult areas, such as the arms, calves, medial thighs, and the male breast. A combination of syringe-suction and machine-assisted liposculpture is sometimes used. Tumescent liposculpture has been combined with pulsed CO2 laser surgery to produce a more effective and less invasive treatment for the aging face, neck, and jowls. External ultrasound-assisted liposculpture can produce excellent results.

Adult↗