David P Johnson

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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(More)
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(More)
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(More)
In order to define the predisposing factors and outcome of infected arthroplasty of the knee, a retrospective analysis of a consecutive series of 471 knee arthroplasties was performed. There were 23 cases of superficial wound infection and 25 of deep infection. Superficial wound infection alone resulted in a painfree gait, with little limitation of(More)
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(More)
Early mobilisation after arthroplasty of the knee sometimes results in wound breakdown. The two commonly used incisions, the anterior midline and the medial parapatellar incisions, were compared in order to determine which had the best potential for wound healing. Study of the cleavage lines around the knee demonstrated that the medial parapatellar incision(More)
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(More)
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 <(More)
Atlanto-axial rotatory fixation is one of a spectrum of rotatory abnormalities of the atlanto-axial joint. Rotatory fixation without anterior displacement of the atlas (Type I) has been reported in only a few cases in which there has been a prolonged interval between injury and diagnosis. The majority of these cases eventually required cervical fusion for(More)
This study tested the hypothesis that the posterior fibers of the patellar tendon are subjected to higher tensile strains than the anterior fibers in response to quadriceps tension. The quadriceps tendon was loaded to 1 kN in 10 human cadaver knees and the tensile strain was measured in the anterior and posterior fibers of the patellar tendon. The central(More)