St. Anthony Hospital

Since 1991, 5760 knee arthroplasty procedures done by 53 surgeons have been registered in a community joint implant registry and were reviewed regarding initial revision done within the healthcare system. The 168 revisions done represented 2.9% of the knee arthroplasties between September 1991 and December 2002. Survival was defined as the absence of revision surgery. Death was considered a censored event. Cumulative survival rates for the different total knee arthroplasty configurations were: cemented total knee arthroplasty with all-polyethylene tibia, 99.2%; cemented total knee arthroplasty with metal-backed tibia, 96.3%; hybrid total knee arthroplasty, 89.3%; and unicondylar knee arthroplasty, 87.2%. Cemented total knee arthroplasty with metal-backed tibia had better survival than hybrid total knee arthroplasty, ingrowth total knee arthroplasty, and unicondylar knee arthroplasty. Cemented total knee arthroplasty with a metal-backed tibia did not have better survival than cemented total knee arthroplasty with an all-polyethylene tibia. Gender was not related to survival. Age was related to survival, with older patients' knees surviving longer. Aseptic loosening or wear was the cause of revision in 40.8% of patients having total knee arthroplasty and 46.6% of patients having unicondylar knee arthroplasty, whereas progression of arthritis necessitated unicondylar knee revision in 51.2% of patients having that procedure. This study presents further evidence of the value of and ongoing need for total joint registries. Cemented total knee arthroplasty with all-polyethylene tibia and with metal-backed tibia showed more than 95% 10-year cumulative survival. Hybrid total knee arthroplasty, ingrowth total knee arthroplasty, and unicondylar knee arthroplasties did not show such good results.

UNLABELLED: Operative options for the younger patient with an arthritic knee remain controversial. We prospectively followed 1047 patients 55 years old or younger who underwent knee arthroplasty in a community joint registry over a 14-year period. Patients were implanted with 1047 joints of three predominant designs by 48 surgeons in four hospitals associated with a community joint registry. The mean age for this cohort was 49.8 years, and 62.8% (657/1047) of the patients were female. There were a total of 73 revisions performed, 5.6% (37/653) in women and 9.2% (36/394) in men. Cemented TKAs performed best, with a cumulative revision rate of 15.5%, compared to 32.3% in unicompartmental knee arthroplasty (UKA) patients and 34.1% in cementless designs. Men had a higher cumulative revision rate than women, 31.9% compared to 20.6%. Adjusting for implant type and gender, there was no difference in cumulative revision rate based on diagnosis (OA versus other) or age group (< or = 40, 41-45, 46-50, 51-55 years) or between cruciate-retaining and -substituting designs. Eighty five percent of cemented TKA implants survived at 14 years in the population under 55 years of age in this community registry. Cementless designs and UKA increased revision risk independently. LEVEL OF EVIDENCE: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Since 1991, 5760 knee arthroplasty procedures done by 53 surgeons have been registered in a community joint implant registry and were reviewed regarding initial revision done within the healthcare system. The 168 revisions done represented 2.9% of the knee arthroplasties between September 1991 and December 2002. Survival was defined as the absence of revision surgery. Death was considered a censored event. Cumulative survival rates for the different total knee arthroplasty configurations were: cemented total knee arthroplasty with all-polyethylene tibia, 99.2%; cemented total knee arthroplasty with metal-backed tibia, 96.3%; hybrid total knee arthroplasty, 89.3%; and unicondylar knee arthroplasty, 87.2%. Cemented total knee arthroplasty with metal-backed tibia had better survival than hybrid total knee arthroplasty, ingrowth total knee arthroplasty, and unicondylar knee arthroplasty. Cemented total knee arthroplasty with a metal-backed tibia did not have better survival than cemented total knee arthroplasty with an all-polyethylene tibia. Gender was not related to survival. Age was related to survival, with older patients’ knees surviving longer. Aseptic loosening or wear was the cause of revision in 40.8% of patients having total knee arthroplasty and 46.6% of patients having unicondylar knee arthroplasty, whereas progression of arthritis necessitated unicondylar knee revision in 51.2% of patients having that procedure. This study presents further evidence of the value of and ongoing need for total joint registries. Cemented total knee arthroplasty with all-polyethylene tibia and with metal-backed tibia showed more than 95% 10-year cumulative survival. Hybrid total knee arthroplasty, ingrowth total knee arthroplasty, and unicondylar knee arthroplasties did not show such good results.

This paper describes a study of the cylinder pressure and flow in an oil hydraulic axial piston pump. A comparison is made between a theoretical model based on the effects of fluid compliance within the cylinder, and an improved model which accounts for the influence of oil momentum in the port plate region. The improved model is validated by comparison with experimental test results and is used to analyze the influence of port plate and relief groove design on cylinder pressure and pump flow ripple. A steeply sloping triangular cross-section groove was found to be the most satisfactory design.

A group of 182 patients with subcalcaneal pain related to sports activity was studied to determine injury types and patterns. Running/jogging produced the greatest percentage of subcalcaneal injuries, 76%. A survey was done of the specific types of heel pain, plantar fasciitis and median calcaneal neuritis. A review of each entity was given and surgical approach was detailed. Subcalcaneal surgical decision making is based on six specific tenets: correct diagnosis; approximately 12 months of conservative treatment; EMG for diagnosis and appropriate nerve blocks; thorough knowledge of the anatomy or complete review; patient understanding that surgery may not give a good enough result to allow the return to high performance athletics; and correct and appropriately directed surgery.

OBJECTIVE: To determine the long-term results of distraction osteogenesis of the mandible for upper airway obstruction in children with micrognathia. STUDY DESIGN: Case series with chart review. SETTING: Tertiary care children's hospital. SUBJECTS AND METHODS: The records of a pediatric otolaryngology practice and tertiary children's hospital were searched for patients treated with bilateral mandibular distraction osteogenesis for upper airway obstruction. Patients were selected if greater than three years of follow-up data were available. Data were analyzed for airway and feeding outcomes, and long-term surgical complications were identified. RESULTS: Thirty-two patients met study criteria. Of the 11 patients who had tracheotomy prior to distraction, seven were decannulated after the procedure. Seventeen patients needed perioperative gastrostomy. Seven are now able to feed orally. Fifteen patients treated with mandibular distraction were able to avoid gastrostomy tube placement altogether. The complication of open bite deformity was experienced by nine patients (28%). Five of 32 patients (16%) had tooth malformation, tooth loss, or dentigerous cyst formation while an additional three patients (9%) had long-term facial nerve injury. Nineteen patients (59%) were under three months old at the time of their distraction. Only one of these patients (5.2%) required an additional distraction procedure. CONCLUSION: Long-term follow-up data on patients treated with mandibular distraction for upper airway obstruction show sustained airway improvement. Additionally, micrognathic children treated with distraction have improved outcomes in oral feeding with a relatively low rate of long-term complications. It remains important to follow these patients to monitor the need for secondary reconstructive procedures.

UNLABELLED: The advantages of the monoblock design and lower cost have prompted renewed interest in the all-polyethylene tibia in total knee arthroplasty. We prospectively followed patients with all-polyethylene tibial total knee arthroplasties over a 14-year period. Since 1991, 443 total knee arthroplasties using an all-polyethylene tibia component were implanted by 12 surgeons in four hospitals associated with a community registry. One of three designs was used in over 98% of cases. The mean age of the patient population was 77 years and 78% were female. Ninety-three patients died with their prosthesis intact. Three revisions were performed on this population with mean followup of 66.3 months (range, 0-158 months). Kaplan-Meier survival analysis revealed 99.4% survival at 14.3 years with revision for any reason as the end point. With aseptic loosening or wear as the revision reason, survival is 99.7% at 14.3 years. Total knee arthroplasty with one of the three contemporary congruent all-polyethylene tibia designs used in this registry performed extremely well in this population; savings for this group (compared to those with a metal-backed component) was estimated at $729 per case. If all patients older than 75 years of age in our registry had received an all-polyethylene tibia, the estimated savings for the implant alone would have been $1.28 million. LEVEL OF EVIDENCE: Level II, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

The running symposium has been designed to demonstrate to the reader the basic mechanics of the running gait, as compared to normal walking. It is imperative in order to understand the nature of the problems seen in runners to understand the forces and motions which are occurring in the various joints of the lower extremity, so that as much as possible, treatment can be based upon accurate anatomical diagnoses, rather than empiric treatment. The second part of this symposium discusses the nature of the injuries seen in the lower extremity in runners. Suggestions are made as to how to manage the problems as well as their prevention. Finally, a comment is included on the nature of the running shoe and on shoe selection.

Ever wondered what it's like to be a resident medical officer in a private hospital? Khurshid Ghani, Paul Hadway, and Ken Anson think it's a useful experience with time to study on the job

Clinical failures of all-polyethylene tibial components in total knee arthroplasty generally have been failures of design, not materials. The current study was designed to compare a modern congruent all-polyethylene tibial component with a metal-backed tibial component with the same articular design and geometry. All patients older than 60 years of age requiring total knee arthroplasty were randomized prospectively to receive either a cemented posterior cruciate ligament-retaining all-polyethylene component or a metal-backed tibial component with identical articular surfaces. All patients received identical cemented femoral and all-polyethylene patellar implants. The mean age of the patients was 69 years, and the mean American Society of Anesthesiology score was 3. The diagnosis was osteoarthritis in 92% of this population. Three hundred twenty-four total knee arthroplasties in 296 patients were performed; 213 joints (111 all-polyethylene tibias and 102 metal-backed tibias) with a minimum of 3 years followup (mean, 49 months) are reported. The preoperative Knee Society knee score in the group of patients who received an all-polyethylene tibial component was 38 points, improving to 84 points at latest followup, whereas in the group of patients who received a metal-backed tibial component, the score improved from 35 to 85 points. Functional scores increased from preoperative values of 56 to 74 points in the patients who received all-polyethylene tibial components, and 57 to 72 points in the patients who received metal-backed tibial components. Range of motion measured at latest followup averaged 106 degrees in patients who received an all-polyethylene tibial component and 107 degrees in the patients who received a metal-backed component, and postoperative tibiofemoral alignment averaged 6 degrees valgus for both groups. There were 13 reoperations for instability, patellofemoral problems, or deep infection, but none for aseptic loosening or wear in either group. These differences were not statistically significant, nor were any measures of patient satisfaction or clinical outcome between the two groups in this period. Total knee arthroplasty with a well-designed, contemporary congruent all-polyethylene tibial component functions equivalently to its metal-backed tibial counterpart at 3- to 5-year followup in this patient population, and is less costly ($675).

The narrowed bony canal in the achondroplastic spine cases varied neurologic problems. The specific anatomic areas seem not to have been directly measured in an autopsy specimen. An achondroplastic spine was examined radiographically and found to show decreased interpediculate distance, thick pedicles, inferior facet thickness, and for animal stenosis in the lumbar canal. These findings have direct application to surgical treatment insofar as simple laminectomy for achondroplastic dwarfs may be insufficient to produce neural canal decompression. The problem is likely to require thorough exposures of facets and foramen.

Stroke as a complication of carotid endarterectomy has been extensively reviewed. Considerably less attention has been directed to local injuries of the cranial nerves and their branches. Verta, Hertzer, Imparato, DeWeese, and Matsumoto have reported experience with these injuries. DeWeese found a 9.7% rate of cranial nerve injury, while in Hertzer's series, 15% of patients had nerve dysfunction in the early postendarterectomy period. In 1980, Liapis in a preliminary report found that when postoperative examination was supplemented by detailed evaluation by speech pathologists, the incidence of early abnormalities reached 27%. The purpose of this study was to expand upon Liapis' early observation and to clarify the contribution of the speech pathologists in identifying cranial nerve dysfunctions, specifically those resulting in motor speech abnormalities, following carotid endarterectomy.

Recurrent compartment syndromes of the lower extremity, which usually occur in conjunction with intense use of muscle groups, can be briefly defined as an uncomfortable circulatory disturbance associated with a pathologic increase in total intramuscular pressure. This syndrome has been reported in each of the four compartments of the leg but not in the thigh. Characteristic features of clinical presentation and physical examination are reviewed in this report. We have found that an intracompartmental pressure test (Whitesides Jr, TE, Haney TC, Morimoto K, et al: Tissue pressure measurements as a determinant for the need of fasciotomy. Clin Orthop 113: 43-51, 1975) is an invaluable diagnostic aid. A case involving the medial hamstring groups, with characteristic historical presentation, intracompartmental pressure elevation, and excellent response to fasciotomy, is presented and discussed. The only effective treatment in this case was fasciotomy.

BACKGROUND: We examined the procedural outcomes of chronic total occlusions (CTO) percutaneous coronary interventions in patients with prior coronary artery bypass graft surgery (CABG). METHODS AND RESULTS: We compared the clinical, angiographic characteristics and outcomes of 3486 CTO interventions performed in patients with (n=1101) and without (n=2317) prior CABG at 21 centers. Prior CABG patients (32% of total cohort) were older (67±9 versus 63±10 years; P<0.001) and had more comorbidities and lower left ventricular ejection fraction (50% [40-58] versus 55% [45-60]; P<0.001). The CTO target vessel in prior CABG patients was the right coronary artery (56%), circumflex (26%), and left anterior descending artery (17%). The mean J-CTO (2.9±1.2 versus 2.2±1.3; P<0.001) and PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention; 1.5±1.1 versus 1.2±1.0; P<0.001) score was higher in prior CABG patients. Retrograde (53% versus 30%, P<0.001) and antegrade dissection reentry (35% versus 28%; P<0.001) techniques were used more frequently in prior CABG patients. Prior CABG patients had lower technical (84% versus 89%; P<0.001) and procedural (82% versus 87%, P<0.001) success, but similar incidence of in-hospital major complications (3.1% versus 2.5%; P=0.287). In-hospital mortality (1% versus 0.4%; P=0.016) and coronary perforation (7.1% versus 3.1%; P<0.001) occurred more frequently in prior CABG patients, however, CABG patients had a lower incidence of pericardial tamponade (0.1% versus 1.0%; P=0.002) and pericardiocentesis (0% versus 1.3%; P<0.001). CONCLUSIONS: In a large multicenter CTO percutaneous coronary interventions registry, prior CABG patients had lower success rate but similar overall risk for complications, although mortality was higher and the incidence of tamponade was lower. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02061436.

OBJECTIVE/BACKGROUND: To examine the role of carotid stenosis (CS) and other independent risk factors of perioperative stroke, following transcatheter aortic valve implantation (TAVI). MATERIALS AND METHODS: Using data from the National Inpatient Sample database for analysis, patients who underwent TAVI were identified using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Various preoperative and perioperative risk factors and their association with perioperative strokes were studied. RESULTS: Data on 7566 patients who underwent a TAVI procedure from 2012 to 2013 were extracted. The average age of the patient population was 81.2 ± 0.32 years. The overall perioperative stroke rate in our patient cohort was 2.79%. Majority (94.6%) of the strokes were ischemic. Multivariate analysis showed the following independent risk factors for perioperative strokes after TAVI: female gender odds ratio (OR) = 2.25 (95% confidence interval [CI], 1.42-3.57), higher van Walraven score OR = 6.6 (95% CI = 3.71-11.73), bilateral CS OR = 4.46 (95% CI = 2.03-9.82), and TAVI with a cardiac procedure done under cardiopulmonary bypass OR = 2.84 (95% CI = 1.57-5.14). CONCLUSION: Bilateral carotid disease is a significant risk factor for perioperative strokes following TAVI. Preoperative screening with carotid Doppler to identify high-risk patients appears to be warranted. In addition, patients of female gender were found to have an increased risk for carotid disease.

BACKGROUND: Aprotinin has been shown to reduce blood transfusion in cardiac surgery. Aprotinin inhibits activated protein C (APC). Patients with factor V (FV) Leiden have an inherited resistance to APC proteolysis. If the inhibition of APC by aprotinin contributes to its beneficial effect in cardiac surgery, then patients with FV Leiden undergoing cardiac surgery might be expected to require less transfusion than patients without FV Leiden. However, the use of aprotinin in such patients also could compromise the protein C regulatory pathway and precipitate a clinical thrombotic event. STUDY DESIGN AND METHODS: Patients undergoing cardiac surgery were studied for the presence of the FV Leiden defect by the use of a Russell's viper venom clot-based assay and polymerase chain reaction. The total amount of blood transfused was recorded for each patient. The effect of aprotinin on the plasma of normal and FV Leiden patients was studied. Further studies were performed on the direct inhibition of APC by aprotinin. RESULTS: Over an 18-month period, 162 patients were studied, of whom 13 (8%; 95% CI, 4.3-13.3%) were positive for FV Leiden. These 13 had a smaller requirement for blood transfusion than the to 13 matched controls. In vitro, aprotinin induced a FV Leiden defect in normal plasma and exacerbated the defect in the plasma of FV Leiden patients. Aprotinin inhibited APC in a dose-dependent manner, and kinetic analysis showed competitive inhibition with an inhibition constant of 4.5 microM (250 Kallikrein inhibitor units/mL). CONCLUSION: The inhibition of APC by aprotinin may contribute to its hemostatic effect. The use of aprotinin in patients with FV Leiden could cause extreme dysfunction of the protein C regulatory pathway, which could result in clinical thrombosis.

The incidence of tibial-talar dislocations without fracture is unknown and has been sparsely reported in the literature. The diagnosis of the injury is straightforward with the appropriate examination and roentgenograms. Good to excellent results can be achieved with open or closed dislocations treated by closed reduction and immobilization for 4-6 weeks. Although open dislocations require irrigation, debridement, and possibly delayed closure, controversy exists with regard to acute ligament repair. Because good to excellent results are possible without acute ligament repair, and delayed repair on reconstruction can be accomplished with good outcomes, we recommend treating these injuries without ligament repair.

One-hundred sixty-four knee injuries in runners with abnormal foot configuration were reviewed and followed. Definite injury patterns related to pronation and cavus configuration of the foot are seen, and specific treatment can be made.

OBJECTIVES: To describe pediatric costochondral graft reconstruction of the absent mandibular condyle and to report the short-term and long-term outcomes and complications associated with performing this procedure in young children. STUDY DESIGN: Case series with a retrospective chart review. SETTING: Pediatric otolaryngology clinic and tertiary children's hospital in a metropolitan area. SUBJECTS AND METHODS: All children treated for an absent mandibular condyle with a costochondral graft at Children's Hospitals and Clinics of Minnesota were identified from 2002 through 2011, and a retrospective chart review was performed. RESULTS: Ten patients aged 3 to 11 years were identified. The most common diagnosis, in 8 of 10 patients, was oculo-auriculo-vertebral syndrome. Three of the patients had a tracheostomy, of which 1 was decannulated following condylar reconstruction. Functional improvement, defined as improved symmetry, chewing, or better oral opening, was observed in 8 of 10 patients. Five patients have required no further surgeries to date, with a mean follow-up time of 3.9 years. Severe overgrowth of the graft was noted in 1 case, and partial or complete resorption of the graft was also noted in 3 cases. Overgrowth occurred after 5.7 years, whereas resorption occurred after an average of 2.5 years. CONCLUSIONS: Costochondral grafts are an excellent surgical treatment option for children with severe mandibular malformations. Short-term results show particular improvement in function and mandibular alignment. The mean follow-up time with no revision surgery was substantial and indicates that rib grafting is a good addition to the armamentarium of treatment for this patient population.

A 54-year-old woman had a 3 year history of a recurrent bilateral axillary rash during the summer months. Both axillae showed hyperkeratotic, fissured and cobblestone plaques. Skin biopsy showed the histology previously defined as axillary granular parakeratosis. This finding may indeed represent an unusual contact reaction to anti-perspirants interfering with epidermal keratinization.