Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC). Findings In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683–0·717]). Interpretation In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required. Funding British Journal of Surgery Society

Outcomes of total knee arthroplasty following high tibial osteotomy

BACKGROUND: Total knee arthroplasty (TKA) following high tibial osteotomy (HTO) is a technically demanding procedure with varying results. The purpose of our study was to analyze the clinicoradiological results of TKA following HTO and to identify the factors that may influence the final outcome. MATERIALS AND METHODS: 55 patients (58 knees) who had undergone a previous HTO were treated with a TKA from 1991 to 2009. There were 34 female and 21 male patients. The average age was 61.9 years (range 52-82 years) and the average weight was 79.5 kg (range 54-106 kg), with an average body mass index of 29.6 (range 21.8-34.6) at the time of TKA. The knee society scores (KSSs) and knee society functional scores were evaluated for every patient pre and postoperatively and the results evaluated. RESULTS: The mean period of followup was 11.2 years (range 3-18 years) and the patients were followed up every year. The average KSS score at final followup improved from 38.5 (range 0-80 points) preoperatively to 88.5 postoperatively (range 35-95 points) (P < 0.05). The mean femorotibial angle corrected from 6.8 degrees (range 5-12°) varus preoperatively to a valgus of 4.4 (2-8°) degrees postoperatively. The average joint line height improved to an average of 9.6 mm (range 4.4-22 mm) (P < 0.01) at the last followup. The average Insall Salvatti Ratio also improved (average 1.11 preoperative - 1.21 average postoperative) (P < 0.05). The average range of motion improved to 108° (range 85°-125°) from 76° preoperative (range 55°-100°) (P < 0.01). CONCLUSION: Although TKA postHTO is a demanding surgery however, with newer component designs, results are comparable to primary TKA. Technical difficulties in exposure can sometimes lead to component malpositioning, which can affect the final outcome. Inadequate soft tissue balancing and limb malalignment should always be kept in mind. Regular followup to look for evidences of loosening is advised in such patients]

Revision Total Knee Arthroplasty for Septic versus Aseptic Failure

Purpose.To compare the medium-term outcome of revision total knee arthroplasty (TKA) for septic versus aseptic failure.Methods.Records of 142 patients who underwent revision TKA by a single senior surgeon for septic (n=65) or aseptic (n=77) failure were reviewed. In the septic group, 67 knees in 42 women and 23 men were included. In the aseptic group, 88 knees in 51 women and 26 men were included. The Knee Society Score was measured. The Kaplan Meier survival curve at months 36, 60, and 95 was plotted, with revision as the end point. The survival rates at each specific time point between the 2 groups were compared using the Z test.Results.The Knee Society Scores improved 18% from 51 to 69 in the septic group and 18% from 52 to 70 in the aseptic group (p=0.72). The range of motion improved 30% from 72° to 102° in the septic group and 39% from 62° to 100° in the aseptic group (p&lt;0.001).Conclusion.Results of the 2 groups were similar in terms of the Knee Society Score, range of motion, and the Kaplan-Meier survivorship.</jats:sec

Total knee arthroplasty in extra articular deformities: A series of 36 knees

BACKGROUND: The presence of extra articular deformities either in the femur or the tibia with arthritis of the knee makes total knee arthroplasty (TKA) technically demanding. The purpose of this study is to report outcomes with Total Knee Arthroplasty in patients with arthritis of the knee associated with extra articular deformity by intraarticular resection and soft tissue balancing. MATERIALS AND METHODS: Thirty six knees (32 patients) who had arthritis of the knee associated with extra articular deformity, underwent total knee arthroplasty between 1999 and 2006 were included in this retrospective analysis. All patients had intraarticular resection with soft tissue balancing to correct the deformity. Full length weight bearing anteroposterior X-rays, Knee society scores, and Knee range of motion was recorded pre- and postoperatively. RESULTS: The mean period of followup was 85 months (range 42-120 months). The deformities amenable to correction by intraarticular resection in our series were Femur- Coronal plane 11°-18° (mean 16.2°) Saggital plane 0°-15° (mean 10.1°) Tibia - Coronal plane 12°-24° (mean 21°). There was an improvement in the range of motion from mean of 54° preoperatively to 114° postoperatively (P value < 0.05). The Knee Society- Knee Score improved from 37 points to 85 points postoperatively (P value < 0.05). The functional score improved from a mean value of 19 to a mean of 69.5 at followup (P < 0.01). The preoperative hip knee ankle angle in the coronal plane improved from a mean of 14° ± 2° varus (26° varus to 4° valgus) to a mean of 2° ± 0.6° varus (6° varus to 2° valgus). CONCLUSION: With a good preoperative planning and templating, intraarticular bone resection and good soft tissue balancing both in flexion and extension, correction would be possible in majority of extraarticular deformities

Surgical options for chronic patellar tendon rupture in total knee arthroplasty

The purpose of this study was to compare mid-term results of three different reconstructive techniques for chronic patellar tendon disruption after total knee arthroplasty (TKA). Several surgical techniques have been proposed, but to date it is still unclear which is the best solution. The hypothesis was that allografts provide better functional results than autografts in restoring a correct joint function