Rapid Discharge to Home After Total Knee Arthroplasty Is Safe in Eligible Medicare Patients.

BACKGROUND: This study was aimed at assessing the risk of readmission for Medicare patients discharged home within a day of total knee arthroplasty (TKA) compared to those discharged on day 2 or beyond in a community medical center. METHODS: A hospital inpatient database was queried for all unilateral, primary TKAs performed on patients 65 years or older from January 1, 2013, to December 31, 2015. A total of 2287 patients met the study criteria, of which 1502 were discharged within a day (short stay), and 785 were discharged on day 2 or beyond (traditional stay). The main outcome measures were all-cause 30-day and unplanned 90-day readmissions. RESULTS: Short-stay patients did not experience a higher 30-day readmission rate (1.1%) compared to the traditional-stay patients (2.7%), nor did they experience a higher rate of unplanned 90-day readmissions (1.7% vs 3.6%). The short-stay group had more favorable demographics compared to the traditional-stay group. Logistic regression results revealed that none of the demographic factors considered had a statistically significant impact on 30-day readmission odds for either group. For unplanned 90-day readmissions, the results showed that for the short-stay patients, with the exception of age, none of the other demographic factors had significant impact on readmission odds and none were significant for the traditional-stay group. CONCLUSION: Our results suggest that the Medicare patients meeting discharge criteria and discharged home within a day of TKA do not have an increased risk of 30-day and 90-day readmission.

Long-term performance of ceramic and metal femoral heads on conventional polyethylene in young and active patients: a matched-pair analysis.

BACKGROUND: Ceramic femoral heads produce less wear of the opposing polyethylene than do metal femoral heads in wear simulation studies. This is a matched-pair analysis of the wear of ceramic and metal femoral heads on conventional polyethylene in uncemented total hip replacements in young, active patients at a minimum of fifteen years of follow-up. METHODS: From June 1989 to May 1992, thirty-one matched pairs of alumina ceramic or cobalt-chromium metal femoral heads were identified. Patients were matched on the basis of age, sex, body weight, diagnosis, and activity level. The mean age was 55 ± 9 years (range, twenty-three to sixty-five years) at the time of surgery. All procedures were performed with a posterolateral surgical approach by a single surgeon using press-fit Ranawat-Bernstein femoral stems, Harris-Galante-II acetabular cups, GUR 4150 conventional polyethylene (sterilized in argon), and 28-mm-diameter femoral heads. Wear measurements were performed by two independent observers using the computer-assisted Roman software. RESULTS: The average duration of follow-up was 17 ± 1.7 years (range, fifteen to twenty years). The mean Hospital for Special Surgery hip scores (and standard deviation) in the ceramic and metal groups were 39 ± 4 and 40 ± 3 at the time of final follow-up. The University of California Los Angeles activity score at the time of the final follow-up was 6 ± 2 for both groups. The mean wear rates for the ceramic group and the metal group were 0.086 ± 0.05 mm/yr and 0.137 ± 0.05 mm/yr, respectively (p = 0.0015). There was one reoperation in the ceramic group because of distal femoral osteolysis. There were three failures in the metal group, requiring isolated liner exchange in two hips and revision of the acetabular component in one hip because of wear-induced osteolysis and/or loosening that caused symptoms. Five hips in the ceramic group and six hips in the metal group had radiographic evidence of acetabular or femoral osteolysis, but none were symptomatic. CONCLUSIONS: Ceramic femoral heads produced significantly less wear on conventional polyethylene liners at the time of long-term follow-up than did metal heads in this matched-pair analysis of young and active patients with uncemented fixation.

Computerized range of motion analysis following dual mobility total hip arthroplasty, traditional total hip arthroplasty, and hip resurfacing.

Newer arthroplasty designs claim to provide superior range of motion (ROM) and greater stability than their predecessors. However, there is no way to compare ROM of implant systems in an equivalent anatomical environment in a clinical setting. This study used computer-aided design to compare ROM after hip resurfacing, 28 mm THA, 36 mm THA, and anatomic dual mobility (ADM) THA in 3D models of 5 cadaver pelvises. ROM to impingement was then tested in 10 different motions and a one-way ANOVA was used to compare results. The hip resurfacing resulted in restricted ROM compared to the other 3 models in all motions except adduction. The ADM, 36 mm, and 28 mm THA resulted in similar ROM. Dual mobility constructs provide comparable ROM in patients where large head THA is not appropriate.

Prevalence and preoperative demographic and radiographic predictors of bilateral femoroacetabular impingement.

BACKGROUND: Patients with symptomatic femoroacetabular impingement (FAI) frequently have bilateral deformity and inquire about the prognosis of their contralateral, asymptomatic hip. Idiopathic coxarthrosis has been established as an independent risk factor for joint failure on the other side. PURPOSE: To determine the prevalence of bilateral arthroscopic treatment for FAI and to identify predictive patient demographics and radiographic findings for bilateral, symptomatic disease. STUDY DESIGN: Case control study; Level of evidence, 3. METHODS: Over a 2-year period, patients receiving single-sided FAI surgery for pain and radiographic deformity were identified as unilateral. In the same period, patients undergoing their second side were labeled bilateral, regardless of when the first surgery was performed. Proximal femoral alpha angle; lateral center edge angle; sagittal center edge angle; acetabular version at 1, 2, and 3 o'clock; and femoral torsion were measured on preoperative computed tomography scans. RESULTS: The unilateral group included 514 patients, and the bilateral group included 132 patients. Women composed 48% of the unilateral group but only 35% of the bilateral group (P = .006). The mean age of unilateral patients was 30.3 (±10.7) years and 27.6 (±9.7) years for the first side of bilateral patients (P = .010). The bilateral hips had higher alpha angles (63.8° vs 59.8°, P = .004), less acetabular anteversion at the 3-o'clock position (13.0° vs 15.9°, P < .001), and similar femoral torsion (15.1° vs 15.5°, P = .793) compared with unilateral hips. A multivariable logistic regression model found that for every 5 years of younger age, 5° higher alpha angle, and 5° decrease in 3-o'clock acetabular version, patients were more likely to undergo bilateral treatment for FAI, by 13.5%, 14.5%, and 25.5%, respectively. In a side-to-side comparison of both hips in bilateral patients, alpha angle (r = 0.72) and acetabular version at 1 o'clock (r = 0.73) showed high correlation. CONCLUSION: Male sex, younger age, higher alpha angles, and reduced acetabular anteversion at initial presentation are significant risk factors for identifying patients who may ultimately require bilateral surgery for symptomatic FAI. Among bilaterally treated patients, no radiographic parameters were predictive of which side would require treatment first. Patients with FAI requiring surgery should be closely monitored for contralateral hip disease.

Increased range of motion to impingement with large head total hip arthroplasty: point of diminishing returns.

Large head total hip arthroplasty (THA) is known to increase range of motion to impingement and decrease risk of dislocation, however, this is dependent on accurate component positioning and patient anatomy. In this study, a computer-aided design model was used to determine the effects of component positioning on range of motion to impingement with increasing head size. Three-dimensional models were made of 7 cadaver CT scans and virtual THA was performed with a conventional implant system. Theoretical range of motion to impingement was tested before and after the components were implanted in flexion, extension, internal/external rotation, abduction, adduction, and flexed internal/external rotation. Range of motion increased non-linearly in every motion except for external rotation and adduction with increasing head size, with gains in ROM limited by osseous impingement. Use of large head THA leads to increased ROM to impingement, but with larger head sizes, benefits are limited by bony anatomy.

Hip injuries in the overhead athlete.

BACKGROUND: The overhead athlete is at risk for shoulder and elbow injuries. However, the mechanics associated with overhead sports also place athletes at risk for hip injuries. Advancements in hip arthroscopy have identified femoroacetabular impingement (FAI) and instability as potential contributors to labral and chondral pathology in this athletic population. QUESTIONS/PURPOSES: We therefore determined whether hip function improves after arthroscopic treatment of FAI in overhead athletes and the rate at which overhead athletes returned to preinjury level of play. METHODS: We retrospectively identified high-level baseball and lacrosse players (varsity high school, collegiate, and professional) who underwent arthroscopic treatment for FAI. Thirty-four athletes with an average age of 21.4 years met study criteria. There were 16 baseball players and 18 lacrosse players. All patients completed modified Harris hip scores and were assessed for ability to return to preinjury level of play. The minimum followup was 12 months (average, 25 months; range 12-41 months). RESULTS: Mean modified Harris hip scores improved from 70 to 92. Thirty-three of 34 patients were able to return to preinjury level of sports participation. CONCLUSIONS: Arthroscopic management of hip injuries in the high-level overhead throwing athlete can result in a high rate of return to play. Mechanical overload of the hip from impingement and secondary instability can have a substantial effect on hip function and may be the cause of deterioration in athletic performance in some cases. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Septic arthritis of the glenohumeral joint: a review of 23 cases.

Infection of the glenohumeral joint is an uncommon yet devastating condition. The objective of this study was to review the incidence, risk factors, presentation, and treatment for this disorder. Twenty-three culture-positive cases of septic arthritis of the glenohumeral joint were identified and treated at the authors' institution between 1986 and 2000. Eighty-seven percent of patients had at least one serious systemic illness, and on average had two. Fifty-two percent had a different primary site of infection identified. Staphylococcus aureus was identified as the infectious organism in 70% of cases, 17% of which were found to be methicillin-resistant S. aureus. Patients admitted to the orthopedic service were more likely to undergo surgical treatment. Patients treated surgically had shorter hospital stays than those treated with serial aspirations alone. Shoulder infections affect patients who are older and have multiple systemic diseases. Surgical treatment of shoulder infections, when compared to aspiration alone, is associated with a shorter hospital stay. Glenohumeral infection is a debilitating affliction even when control of the infection can be achieved.