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P Lotke

Publications and source records attributed to P Lotke.

8 recordsLinked to original sources
PubMed2000

Cost-effectiveness of immediate postoperative radiographs after uncomplicated total knee arthroplasty: a retrospective and prospective study of 750 patients.

We have questioned the value of postoperative radiographs after uncomplicated, primary total knee arthroplasty (TKA). A total of 750 patients were included in this 2-part study. In the first part, we retrospectively reviewed 200 consecutive, primary TKAs to determine if the immediate postoperative radiographs offered any information that altered the clinical course or if these radiographs could serve as baselines for future images. In the second part, 550 patients who underwent an uncomplicated TKA had their first postoperative radiographs taken at the initial visit. These patients were followed prospectively until the 6-week follow-up appointment to determine if any events occurred in which predischarge radiographs would have been useful as a comparison study. Of the 200 patients who underwent a primary TKA, 192 had postoperative radiographs performed before discharge. Among the 192 patients, the radiographs did not alter the postoperative management. In examining overall quality of the radiographs, only 36% were of sufficient quality to provide an accurate baseline for further studies. Total cost was approximately $36,000. In the 550 patients who had the first postoperative radiograph performed at 6 weeks, there were no instances in which radiographs taken before discharge were needed to aid in further management or legal defense. As with total hip arthroplasty, the past standard has been to obtain immediate postoperative radiographs after primary TKA. Although the information obtained in a total hip arthroplasty patient can be clinically important, the practice of obtaining routine, immediate postoperative knee radiographs in the absence of a specific clinical indication does not provide any additional clinical information and does not appear to benefit patient care.

Arthroplasty, Replacement, Knee↗
PubMed1998

Structural motifs in rheumatoid T-cell receptors.

The linkage of rheumatoid arthritis (RA) to HLA-DR haplotypes, high levels of HLA-DR expression, and T-cell infiltration in the joints, indicate a central role for the interaction of T-cell receptors (TCR) with antigen (Ag) + major histocompatibility complex (MHC) complexes in pathogenesis. Receptor analysis in RA has uncovered a restricted heterogeneity of TCR transcripts, suggesting an antigen-driven response. We analyzed the sequence and structural features of RA-associated TCRs in light of the recently published TCR crystal structures. The surface-exposed residues of the third complementarity-determining region (CDR3s) showed preferential use of certain amino acid residues when sequences derived from synovial fluid or tissue were compared with those derived from peripheral blood, particularly for alpha chains. Sequence alignment of oligoclonal synovial TCR CDR3s revealed groupings with similar CDR3 lengths and amino acid compositions, which suggests shared antigen recognition. Given the limitations of analyzing TCR sequences without knowing their structures, we developed several in vivo-activated synovial-tissue Vbeta17 + RA T-cell clones. Two Vbeta17/V alpha7 clones with different CDR3 sequences were analyzed by molecular modeling. Although distinct topologic features were seen, a central patch of residues with similar chemical and geometric characteristics was present in both. Electrostatic maps revealed similar binding surfaces of both alpha domains and central patches, with differences in the beta domains. This suggests that an alpha-domain-focused binding trajectory would allow shared antigen recognition by these TCRs. These studies support recognition of a limited diversity of Ag + MHC complexes by synovial RA TCRs.

Amino Acid Sequence↗
PubMed1998

Total knee arthroplasty in morbidly obese patients.

We reviewed the clinical outcomes of fifty primary total knee arthroplasties that had been performed with cement in forty patients who were considered morbidly obese (a Quetelet index of more than forty). These results were compared with those of 1768 similar procedures, performed during the same time-period by the same surgeon, in 1539 patients who were not morbidly obese (controls). At a mean of approximately five years postoperatively, there was a significant difference between the morbidly obese patients and the control group with regard to the knee and functional scores (84 and 53 points compared with 92 and 67 points; p < 0.00005 for both scores). No significant difference was detected, with the numbers available, with regard to the range of motion or the radiographic score (p = 0.77). The rate of perioperative complications was significantly higher in the morbidly obese patients (p < 0.00005). Of the fifty knees in these patients, eleven (22 percent) had a wound complication, five (10 percent) had an infection, and four (8 percent) had an avulsion of the medial collateral ligament. The five infections developed within twenty weeks after the operation, and three were associated with a wound complication. In comparison, thirty-five (2 percent) of the 1768 knees in the control group had a wound complication, eleven (0.6 percent) had an infection, and none had an avulsion of the medial collateral ligament. We concluded that total knee arthroplasty in morbidly obese patients can be successful but is associated with an increased rate of perioperative complications, including problems with wound-healing, infection, and avulsion of the medial collateral ligament. Alterations in the operative technique for soft-tissue closure and protection of the medial collateral ligament have decreased the rates of complications related to wound-healing and the medial collateral ligament.

Arthroplasty, Replacement, Knee↗
PubMed1997

Continuous passive motion with accelerated flexion after total knee arthroplasty.

The use of continuous passive motion after total knee arthroplasty remains controversial. A new approach, starting continuous passive motion at 70 degrees to 100 degrees flexion in the recovery room (Group I) was evaluated. A randomized, prospective study of 210 consecutive total knee arthroplasties was performed at two institutions. The control population (Group II) started continuous passive motion at 0 degree to 30 degrees, and progressed toward 100 degrees flexion. Flexion at postoperative Day 3 (Group I = 82.5 degrees, Group II = 72.8 degrees), and at discharge (Group I = 89.1 degrees, Group II = 84.3 degrees) were significantly different. There was no significant difference between the groups at 4 weeks (Group I = 5.0 degrees-104.1 degrees, Group II = 5.6 degrees-102.0 degrees), 6 weeks (Group I = 2.3 degrees-104.8 degrees, Group II = 2.7 degrees-103.6 degrees), 12 weeks (Group I = 1.7 degrees-107.7 degrees, Group II = 4.7 degrees-108.2 degrees), or at 1 year (Group I = 0.5 degree-113.2 degrees, Group II = 1.8 degrees-110.5 degrees). In Group I, wound necrosis developed in one patient that required a gastrocnemius flap. This major complication was caused by a tight dressing, and not necessarily to the accelerated flexion continuous passive motion. This investigation shows that continuous passive motion using accelerated flexion allows increased flexion during the hospital stay without increased risk of complications, pain, or blood loss. This has significant implications for achieving safe, early discharge. However, no difference was found at followup of 4 weeks or greater, and this did not add significantly to the final outcome.

Aged↗
PubMed1980

Evaluation and management of subtalar dislocations.

Twenty subtalar dislocations were reviewed in patients seen at the hospital complex of the University of Pennsylvania, 1950--1979. All patients were available for followup examination and roentgenographic review. These were 15 males and five females in the study. Length of followup ranged from 6 months to 23 years, mean, 4.2 years. Medial dislocation was most frequent, occurring in 17 out of 20. All three with lateral dislocations had associated fractures. All of the dislocations were closed injuries and only one patient required open reduction. Immobilization was maintained in a below-knee weight bearing cast for 6 weeks post-reudction. Of the patients, 80% demonstrated significant restriction of motion and 30% had roentgenographic evidence of arthritis. Few were symptomatic. Fourteen had excellent results, two good, two fair, and two poor. In general, a satisfactory result is to be expected with closed reduction following parenteral medication.

Adolescent↗
PubMed1979

Serratus anterior paralysis in the young athlete.

Ten cases of isolated, complete paralysis of the serratus anterior muscle were diagnosed in young athletes during a three-year period. One patient had recurrent partial paralysis of the serratus anterior muscle, the first such case reported. From studies on cadavera and clinical observations, we concluded that paralysis of the serratus anterior muscle results from a traction injury to the long thoracic nerve of Bell. Since full recovery usually occurs in an average of nine months, surgical methods of treatment should be reserved for patients in whom function fails to return after a two-year period. Non-strenuous use of the involved extremity with avoidance of the precipitating activity, followed by exercises designed to maintain the range of motion of the shoulder and to increase the strength of associated muscles, is advocated for treatment of acute or repetitive injuries to the long thoracic nerve of Bell.

Adult↗