Alexander S. McLawhorn

Outcomes After Arthroscopic Treatment of Femoroacetabular Impingement for Patients With Borderline Hip Dysplasia

Background: The outcomes of hip arthroscopy in the treatment of dysplasia are variable. Historically, arthroscopic treatment of severe dysplasia (lateral center-edge angle [LCEA] <18°) resulted in poor outcomes and iatrogenic instability. However, in milder forms of dysplasia, favorable outcomes have been reported. Purpose: To compare outcomes after hip arthroscopy for femoroacetabular impingement (FAI) in borderline dysplastic (BD) patients compared with a control group of nondysplastic patients. Study Design: Cohort study; Level of evidence, 3 Methods: Between March 2009 and July 2012, a BD group (LCEA, 18°-25°) of 46 patients (55 hips) was identified. An age- and sex-matched control group of 131 patients (152 hips) was also identified (LCEA, 25°-40°). Patient-reported outcome scores, including the modified Harris Hip Score (mHHS), the Hip Outcome Score–Activities of Daily Living (HOS-ADL) and Sport-Specific Subscale (HOS-SSS), and the International Hip Outcome Tool (iHOT-33), were collected preoperatively and at 1 and 2 years postoperatively. Results: The mean LCEA was 22.4° ± 2.0° (range, 18.4°-24.9°) in the BD group and 31.0° ± 3.1° (range, 25.4°-38.7°) in the control group (P < .001). The mean preoperative alpha angle was 66.3° ± 9.9° in the BD group and 61.7° ± 13.0° in the control group (P = .151). Cam decompression was performed in 98.2% and 99.3% of cases in the BD and control groups, respectively; labral repair was performed in 69.1% and 75.3% of the BD and control groups, respectively, with 100% of patients having a complete capsular closure performed in both groups. At a mean follow-up of 31.3 ± 7.6 months (range, 23.1-67.3 months) in unrevised patients and 21.6 ± 13.3 months (range, 4.7-40.6 months) in revised patients, there was significant improvement (P < .001) in all patient-reported outcome scores in both groups. Multiple regression analysis did not identify any significant differences between groups. Importantly, female sex did not appear to be a predictor for inferior outcomes. Two patients (4.3%) in the BD group and 6 patients (4.6%) in the control group required revision arthroscopy during the study period. Conclusion: Favorable outcomes can be expected after the treatment of impingement in patients with borderline dysplasia when labral refixation and capsular closure are performed, with comparable outcomes to nondysplastic patients. Further follow-up in larger cohorts is necessary to prove the durability and safety of hip arthroscopy in this challenging group and to further explore potential sex-related differences in outcome.

The anatomy and histology of the bicipital tunnel of the shoulder

BACKGROUND The bicipital tunnel is the extra-articular, fibro-osseous structure that encloses the long head of the biceps tendon. METHODS Twelve cadaveric shoulder specimens underwent in situ casting of the bicipital tunnel with methyl methacrylate cement to demonstrate structural competence (n = 6) and en bloc harvest with gross and histologic evaluation (n = 6). The percentage of empty tunnel was calculated histologically by subtracting the proportion of cross-sectional area of the long head of the biceps tendon from that of the bicipital tunnel for each zone. RESULTS Cement casting demonstrated that the bicipital tunnel was a closed space. Zone 1 extended from the articular margin to the distal margin of the subscapularis tendon. Zone 2 extended from the distal margin of the subscapularis tendon to the proximal margin of the pectoralis major tendon. Zone 3 was the subpectoral region. Zones 1 and 2 were both enclosed by a dense connective tissue sheath and demonstrated the presence of synovium. Zone 3 had significantly greater percentage of empty tunnel than zones 1 and 2 did (P < .01). CONCLUSION The bicipital tunnel is a closed space with 3 distinct zones. Zones 1 and 2 have similar features, including the presence of synovium, but differ from zone 3. A significant bottleneck occurs between zone 2 and zone 3, most likely at the proximal margin of the pectoralis major tendon. The bicipital tunnel is a closed space where space-occupying lesions may produce a bicipital tunnel syndrome. Careful consideration should be given to surgical techniques that decompress both zones 1 and 2 of the bicipital tunnel.

Steroid modulation of cytokine release and desmosine levels in bilateral total knee replacement: a prospective, double-blind, randomized controlled trial.

BACKGROUND The perioperative inflammatory response as measured by elevated levels of interleukin-6 (IL-6) has been linked to acute respiratory distress syndrome, postoperative confusion, and fever. Because of the extent of surgery,patients undergoing bilateral total knee arthroplasty may be at high risk of complications. We had found a significant decrease in IL-6 in patients having bilateral total knee replacement who received two doses of 100 mg of hydrocortisone eight hours apart; however, by twenty-four hours, IL-6 levels were equal to those in the group that received a placebo. In the present study, we investigated whether the administration of three doses would reduce IL-6 levels at twenty-four hours and affect other outcomes such as desmosine level, a marker of lung injury. METHODS After institutional review board approval, a total of thirty-four patients (seventeen patients and seventeen control subjects) were enrolled in this double-blind, randomized, placebo-controlled study. Three doses of intravenous hydrocortisone (100 mg) or placebo were given eight hours apart. Urinary desmosine levels were obtained at baseline and at one and three days postoperatively. The level of IL-6 was measured at baseline and at six, ten, twenty-four, and forty-eight hours postoperatively. Pain scores, presence of fever, and functional outcomes were recorded. RESULTS The level of IL-6 increased in both groups, but was significantly higher in the control group, peaking at twenty-four hours (mean and standard deviation, 623.74 ± 610.35 pg/mL versus 148.13 ± 119.35 pg/mL; p = 0.006). Urinary desmosine levels significantly increased by twenty-four hours in the control group, but remained unchanged in the study group (134.75 ± 67.88 pmol/mg and 79.45 ± 46.30 pmol/mg, respectively; p = 0.006). Pain scores at twenty-four hours were significantly lower in the study group (1.4 ± 0.9 versus 2.4 ± 1.2; p = 0.01) as was the presence of fever (11.8%versus 47.1%; p = 0.03). Range of motion at the knee was significantly greater in the study group (81.6 ± 11.6 versus 70.6 ± 14.0 in the right knee [p = 0.02] and 81.4 ± 11.3 versus 73.4 ± 9.4 in the left knee [p = 0.03]). CONCLUSIONS Hydrocortisone (100 mg) given over three doses, each eight hours apart, decreased and maintained a lower degree of inflammation with bilateral total knee replacement as measured by IL-6 level. Corticosteroids decreased the prevalence of fever, lowered visual analog pain scores, and improved knee motion. The significantly lower values of desmosine in the study group suggest that this treatment may be protective against lung injury.

Periprosthetic Joint Infections Treated with Two-Stage Revision over 14 Years: An Evolving Microbiology Profile

Late periprosthetic joint infection (PJI) occurs in 0.3%-1.7% of total hip arthroplasties (THAs) and 0.8%-1.9% of total knee arthroplasties (TKAs). Surgical debridement, explant, and appropriate antibiotics are imperative for successful treatment. We analyzed organisms from PJIs at one institution for temporal trends over 14 years. Poisson regression model demonstrated a linear increase in infection rate for the following bacteria as the primary organism: MRSA (incidence rate ratio [IRR] = 1.11, P = 0.019), Streptococcus viridans (IRR = 1.18, P = 0.002), and Propionibacterium acnes (IRR = 1.21, P = 0.024). The increase in proportion of these organisms may warrant further discussion on pre-surgical MRSA screening and empiric therapy to include MRSA coverage, increased incubation time to detect P. acnes, and dental prophylaxis against S. viridans.

Variability in the Relationship Between the Distal Femoral Mechanical and Anatomical Axes in Patients Undergoing Primary Total Knee Arthroplasty

Currently, an intramedullary (IM) guide is often used for performing the distal femoral resection in total knee arthroplasty (TKA). However, this method assumes that in most patients, the distal femoral mechanical-anatomical angle (FMAA) is 5°. Preoperative, standing, AP hip-to-ankle radiographs were reviewed in 493 patients undergoing primary TKA, and the FMAA was digitally measured. Correlation coefficients relative to several radiographic measurements, along with demographic variables, were performed. A significant number of patients (28.6%) had an FMAA outside the range of 5° ± 2° (range 2.0°-9.6°). The only measurement demonstrating a fair/moderate correlation with the FMAA was the neck-shaft angle (r = -0.55). Using an IM resection guide, without obtaining AP hip-to-ankle radiographs to determine each patients true FMAA, may lead to malalignment of the femoral component.

Patient specific cutting guides versus an imageless, computer-assisted surgery system in total knee arthroplasty

BACKGROUND Patient specific cutting guides (PSC) in total knee arthroplasty (TKA) have recently been introduced, in which preoperative 3-dimensional imaging is used to manufacture disposable cutting blocks specific to a patients anatomy. The purpose of this study was to compare the alignment accuracy of PSC to an imageless CAS system in TKA. METHODS Thirty-seven patients (41 knees), received a TKA using an imageless CAS system. Subsequently, 38 patients (41 knees), received a TKA using a MRI-based, PSC system. Postoperatively, standing AP hip-to-ankle radiographs were obtained, from which the lower extremity mechanical axis, tibial component varus/valgus, and femoral component varus/valgus mechanical alignment were digitally measured. Each measurement was performed by two blinded, independent observers, and interclass correlations were calculated. A students two-tailed t test was used to compare the two cohorts (p-value<0.05=significant). RESULTS In the PSC cohort, 70.7% of patients had an overall alignment within 3° of a neutral mechanical axis (vs. 92.7% with CAS, p=0.02), 87.8% had a tibial component alignment within 2° of perpendicular to the tibial mechanical axis (vs. 100% with CAS, p=0.04), and 90.2% had a femoral component alignment within 2° of perpendicular to the femoral mechanical axis (vs. 100% with CAS, p=0.2). Interclass correlation coefficients were good to excellent for all radiographic measurements. CONCLUSION While PSC techniques appear sound in principle, this study did not demonstrate patient specific cutting guides to obtain the same degree of overall mechanical and tibial component alignment accuracy as a CAS technique. LEVEL OF EVIDENCE III: Retrospective cohort study.

Management of End-Stage Ankle Arthritis: Cost-Utility Analysis Using Direct and Indirect Costs.

BACKGROUND Total ankle replacement and ankle fusion are costly but clinically effective treatments for ankle arthritis. Prior cost-effectiveness analyses for the management of ankle arthritis have been limited by a lack of consideration of indirect costs and nonoperative management. The purpose of this study was to compare the cost-effectiveness of operative and nonoperative treatments for ankle arthritis with inclusion of direct and indirect costs in the analysis. METHODS Markov model analysis was conducted from a health-systems perspective with use of direct costs and from a societal perspective with use of direct and indirect costs. Costs were derived from the 2012 Nationwide Inpatient Sample (NIS) and expressed in 2013 U.S. dollars; effectiveness was expressed in quality-adjusted life years (QALYs). Model transition probabilities were derived from the available literature. The principal outcome measure was the incremental cost-effectiveness ratio (ICER). RESULTS In the direct-cost analysis for the base case, total ankle replacement was associated with an ICER of

Humeral lengthening and deformity correction with the multiaxial correction system.

14,500/QALY compared with nonoperative management. When indirect costs were included, total ankle replacement was both more effective and resulted in

The Increased Total Cost Associated With Post-Operative Drains in Total Hip and Knee Arthroplasty

5900 and

Discharge to Inpatient Facilities After Total Hip Arthroplasty Is Associated With Increased Postdischarge Morbidity

800 in lifetime cost savings compared with the lifetime costs following nonoperative management and ankle fusion, respectively. At a