Does Lateral Release Change Patellofemoral Forces and Pressures?: A Pilot Study

Background  

One complication of TKA is postoperative anterior knee pain. Balancing retinacular tissue tension to improve patellar tracking is essential in preventing pain. Lateral release might help balance tension although the quantitative changes in patellofemoral force and pressure differentials after lateral release are unknown.     

Are Joint Structure and Function Related to Medial Knee OA Pain? A Pilot Study

Background  

Although the severity of knee osteoarthritis (OA) usually is assessed using different measures of joint structure, function, and pain, the relationships between these measures are unclear.     

Does Norepinephrine Influence Pain Behavior Mediated by Dorsal Root Ganglia?: A Pilot Study

Background  

Postganglionic neurons in the sympathetic nervous system reportedly are involved in lumbar radicular pain and release norepinephrine (NE), a neurotransmitter. Increased numbers of sympathetic nerve fibers have been found in dorsal root ganglion (DRG) neurons in a root constriction model. Whether this is a reasonable model for pain, however, is unclear     

Does Orthopaedic Surgical Training Induce Hypertension? A Pilot Study

Background  

Elevated blood pressure (BP) is associated with increased cardiovascular risks manifested by ischemic heart disease and stroke. Studies of cardiothoracic surgeons and neurosurgeons suggest surgery induces a hemodynamic stress malresponse. However, it is unclear whether these occur in orthopaedic surgeons.     

Does Texturing of UHMWPE Increase Strength and Toughness?: A Pilot Study

Background  

Crosslinked UHMWPE as a bearing surface in total joint arthroplasty has higher wear resistance than conventional UHMWPE but lower strength and toughness. To produce crosslinked UHMWPE with improved mechanical properties, the material can be treated before crosslinking by tension to induce molecular alignment (texture).     

Clopidogrel and Proximal Femoral Fractures: Does Timing of Surgery Affect Blood Loss and Length of Admission? A Preliminary Study Prior to Multicenter Trial

Abstract Introduction:   Clopidogrel is a potent oral antiplatelet agent that is commonly prescribed to patients with cardiovascular disease. Patients presenting with proximal femoral fractures often have cardiovascular comorbidity, with many taking clopidogrel on admission. Scientific literature reports increased surgical bleeding in patients receiving clopidogrel, though not specifically hip surgery. This study looked at whether patients who had a seven-day delay prior to operative treatment had less bleeding than those who did not, and looked at the differences in length of admission between the two groups. Methods:   A retrospective review was undertaken. Patients were identified from the in-patient pharmacy stock records from July 2005 to July 2006. Data was statistically analyzed using the chi-squared test. Results:   Of 21 patients identified, 20 met the inclusion criteria, nine had a seven-day delay before operation (Group A), and 11 had a mean one-day delay (Group B). Mean drop in postoperative hemoglobin was 1.8 g/l in Group A compared to 3.1 g/l in Group B (p < 0.05). Number of complications was similar (Group A = 8 vs. Group B = 9) as was mortality (Group A = 1 vs. Group B = 2). Admission length was longer in patients who had a seven-day delay in surgery (Group A = 32 vs. Group B = 22 days) (p < 0.05). Conclusion:   Patients should be considered for early operation provided there are no additional bleeding risk factors, as although postoperative hemoglobin is lower, mortality and complication rates are similar, and length of admission is shorter.     

Does Tibial Rotation Correlate With Femoral Anteversion? Implications for Hip Arthroplasty

The aim of the study was to assess the magnitude and variability of rotation of ipsilateral femur and tibia and to identify the existence of rotational correlations. Femoral rotation (FR) and tibial rotation (TR) were measured with computed tomography in 151 consecutive patients when total hip arthroplasty was planned. Median FR was 14 degrees (range, -23 degrees to 91 degrees ) and median TR was 38 degrees (range, 15 degrees -76 degrees ). Femoral rotation was significantly higher in females, in left femora, in the presence of secondary osteoarthritis, and in hip dysplasia. Tibial rotation was significantly higher in females. Femoral rotation and TR positively correlated (r = 0.2963, P = .0001). The magnitude of TR and FR was found to be dependent on each other. Disregarding the variability and magnitude of TR may result in asymmetrical foot positioning after correction of FR during total hip arthroplasty.     

Does Dithiothreitol Improve Bacterial Detection from Infected Prostheses? A Pilot Study

Background  

Sonication and scraping of infected prostheses usually are used to improve diagnosis of prosthetic infections, reducing false negatives. Chemical methods that reduce biofilms also may allow higher levels of detection.     

Does Threshold Nighttime Electrical Stimulation Benefit Children With Spina Bifida?: A Pilot Study

Background  

Electrical stimulation is an established treatment for muscle weakness. However, traditional tectonic stimulation is poorly tolerated in children as a result of discomfort. Threshold electrical stimulation performed at night reportedly increases muscle strength in a variety of neuromuscular conditions and has been well tolerated in children.     

Lateral Opening-wedge Distal Femoral Osteotomy: Pain Relief,Functional Improvement,and Survivorship at 5?Years

Background

Distal femoral varus osteotomy may be used to treat valgus knee malalignment or to protect a knee compartment in which cartilage restoration surgery (such as osteochondral or meniscus allografting) has been performed. Medial closing-wedge osteotomy has demonstrated good success in treatment of osteoarthritis in published series, but few studies have evaluated distal femoral lateral opening-wedge osteotomy in terms of correction of deformity, pain and function, and survivorship.

Questions/purposes

(1) Does lateral opening-wedge osteotomy lead to accurate correction? (2) What pain and function levels do patients experience after lateral opening-wedge osteotomy? (3) What are the nonunion, complication, and reoperation rates after lateral opening-wedge osteotomy?

Methods

Between 2000 and 2010, we performed 40 distal femoral osteotomies. Two knees (two patients) underwent a medial closing-wedge osteotomy and were excluded from the present study. Thirty-eight knees (97%) in 36 patients were lateral opening-wedge varus-producing osteotomies; of those, 31 knees (82%) in 30 patients had followup at a minimum of 2 years (mean, 5 years; SD, 2; range, 2–12 years) and comprised the study population. The indications for osteotomy included symptomatic lateral compartment arthritis with clinical valgus deformity or a cartilage or meniscal defect in the lateral compartment with clinical valgus alignment. The study population was stratified into two groups based on reason for osteotomy: patients with isolated symptomatic lateral compartment arthritis (arthritis group; 19 knees [61%]) and patients who underwent joint preservation procedures including osteochondral allograft transplantation or meniscal allograft transplantation (joint preservation group; 12 knees [39%]). Data collection from our institution’s osteotomy database included patient demographics, lower extremity coronal alignment, and operative details. Pain and function were measured preoperatively and postoperatively using the International Knee Documentation Committee (IKDC) score. Time to radiographic union, complications, and reoperations were recorded.

Results

Twenty-one of 31 knees had postoperative radiographic data available for review. Of these, seven of 15 knees in the arthritis group and three of six knees in the joint preservation group were within the correction goal of ± 3° from neutral mechanical alignment. In the arthritis group, the mean IKDC total score improved from 47 (SD, 15) preoperatively to 67 (SD, 10) postoperatively. In the joint preservation group, the mean IKDC total score improved from 36 (SD, 12) preoperatively to 62 (SD, 18) postoperatively. One nonunion occurred in the arthritis group. No postoperative complications were experienced. Ten knees in the arthritis group and six knees in the joint preservation group had additional surgery after the osteotomy, consisting primarily of hardware removal, arthroscopy for cartilage-related conditions, or conversion to arthroplasty. Survivorship at 5 years, with conversion to arthroplasty as the endpoint, was 74% in the arthritis group and 92% in the joint preservation group.

Conclusions

Lateral opening-wedge distal femoral osteotomy was less accurate in correction of valgus deformity than expected, but the procedure was associated with improved knee pain and function scores. Our clinical and radiographic results are comparable to published series evaluating medial closing-wedge distal femoral osteotomy. Achieving our desired correction of ± 3° from neutral alignment was clinically difficult. An improved method of preoperative templating and refinement of the intraoperative technique may improve this. Future studies with more patients and longer followup will provide clarity on this topic.

Level of Evidence

Level IV, therapeutic study.     

Does Surgeon Fellowship Training Influence Outcomes in Hemiarthroplasty for Femoral Neck Fracture?

BackgroundThe aim of this study is to compare the outcomes (90 days and 1 year) of patients with femoral neck fracture undergoing hemiarthroplasty by surgeons with different fellowship training: trauma, arthroplasty, and general orthopedics.MethodsThis study is a retrospective review of consecutive patients undergoing hip hemiarthroplasty for femoral neck fracture from 2010 to 2018. Comorbidities, perioperative details, demographics, injury variables, and time-to-surgery were compared between the fellowship training cohorts, in addition to outcomes including dislocation, periprosthetic joint infection, and mortality at 90 days and 1 year.ResultsA total of 298 hips with an average age of 77.8 years underwent hemiarthroplasty for femoral neck fracture. Arthroplasty surgeons had a significantly shorter operative duration (82 minutes, P = .0014) and utilized the anterior approach more frequently (P < .0001). The general orthopedists had a significantly increased total surgical complication risk compared to both the arthroplasty and trauma fellowship-trained cohorts at both 90 days (11.8% vs 1.6% vs 3.9%, P = .015) and 1 year (18.2% vs 4.9% vs 7.1%, P = .008). The overall mortality risk was 11.7% at 90 days and 22.8% at 1 year. When adjusted for covariates, including comorbidities, gender, age, and preoperative walking capacity, both the arthroplasty fellowship-trained cohort (odds ratio 0.381, 95% confidence interval 0.159-0.912, P = .030) and the general orthopedist cohort (odds ratio 0.495; 95% confidence interval 0.258-0.952, P = .035) had reduced risk of 1-year mortality compared to the trauma fellowship-trained cohort.ConclusionHemiarthroplasty performed for femoral neck fractures may result in fewer complications when performed by arthroplasty fellowship-trained surgeons. An arthroplasty weekly on-call schedule and adjusted institutional protocols may be utilized to improve outcomes and reduce complications.Level of EvidenceLevel II, retrospective cohort.     

Does Youth Baseball Result in Morphologic Changes of the Lateral Elbow? A Prospective MRI Study

BackgroundStress from overhead throwing results in morphologic changes to the shoulder in youth baseball players. With greater valgus torque stresses, the elbow experiences injuries specifically attributed to throwing. However, no previous work that we know of has assessed throwing-related morphologic changes of the elbow without associated conditions.Questions/purposes(1) Do children who play competitive baseball have enlargement or overgrowth of their radial head shape and/or capitellum compared with the nondominant elbow on MRI? (2) Do children who stop playing year-round baseball have less enlargement of the lateral elbow structures than children who maintain a high level of play?MethodsA prospective study was conducted between 2015 and 2018 on preadolescent boys who underwent voluntary MRI of their bilateral elbows before the start of the spring baseball season. Twenty-six children agreed to participate out of a four-team league that was asked to participate; their first MRI was obtained at a mean (range) age of 12 years (10 to 13). We also obtained their history related to throwing and performed a physical examination. Players had a mean of 5.6 years of playing before their first MRI, and half the children (13 of 26) were year-round baseball players. Sixty-two percent (16 of 26) reported being either or both a pitcher or catcher as their primary position. No child was excluded from participation. Three years later, these boys were asked to return for repeat MRI and physical examinations. Fifty-eight percent (15 of 26) of players were still playing at the 3-year MRI. Continued play or new onset of pain was documented. Radiographic measurements were then compared between dominant and nondominant arms, and the differences of these changes were compared between those who had continued playing during the study period and those who had quit. The measurements were made in all three planes of the radial head and capitellum, both osseous and cartilaginous. Measurement intrarater and interrater reliability were in the good-to-excellent range (intraclass correlation coefficient 0.77 to 0.98).ResultsWhen we compared dominant and nondominant arms, we found there was no dominant arm overgrowth (difference between baseline and 3-year measurements) in any measurement; for example, sagittal capitellum measurements in dominant arms were 2.5 ± 1.1 mm versus non-dominant arms: 2.8 ± 1.1 mm (mean difference -0.23 [95% CI -0.55 to 0.08]; p = 0.13). There was only undergrowth of the cartilaginous axial diameter of the radial head (change in dominant: 2.5 ± 1.3 mm; change in nondominant: 3.2 ± 1.7 mm; mean difference -0.64 mm [95% CI -1.2 to -0.06]; p = 0.03). There was no enlargement of the lateral elbow structures when children who continued to play were compared with children who stopped playing; for example, the difference in the bone-only growth ratio of the sagittal radial head to humerus of those still playing was 0.001 ± 0.03 and it was 0.01 ± 0.03 for those not playing (mean difference -0.01 [95% CI -0.04 to 0.01]; p = 0.29).ConclusionIn healthy children who play baseball for multiple years between the ages of 6 to 11 years, continued torque at the elbow from throwing does not result in morphologic changes as it does in the shoulder. Despite evidence that injuries and surgery because of long-term participation in a throwing sport results in a larger radial head and capitellum, our study presents evidence that outside an injured elbow, throwing alone does not appear to change the morphology of the lateral elbow. Therefore, changes to the radial head size could presuppose other elbow pathology and future study could be performed to better evaluate the correlation.Level of EvidenceLevel I, prognostic study.     

Symptomatic Femoroacetabular Impingement: Does the Offset Decrease Correlate With Cartilage Damage? A Pilot Study

Background

Current measures of the reduced head-neck offset such as residual deformity of slipped capital femoral epiphysis (SCFE) including the alpha angle, which measures the femoral head-neck sphericity but does not account for acetabular abnormalities, do not represent the true magnitude of the deformity and the mechanical consequences. The beta angle (angle between the femoral head-neck junction and acetabular rim) accounts for the morphology of both the acetabulum and femur and, thus, may be the more appropriate parameter for assessing SCFE deformity.

Questions/purposes

We determined (1) whether the beta angle could be reliably measured on MRI; and (2) whether the beta angle correlates with the cartilage status.

Methods

We recruited 10 adult patients (mean age, 28 years) with symptomatic cam femoroacetabular impingement and 15 asymptomatic volunteers (mean age, 24 years) to have three-dimensional MRI including delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) for cartilage status assessment. Corresponding alpha angles, beta angles, and acetabular dGEMRIC indices were obtained in seven radial reformats to assess the hip in seven regions (anterior to superior and posterior).

Results

We noted high reproducibility for both alpha and beta angle measurements. The dGEMRIC indices correlated with beta angles in the superoinferior and superior regions but not the alpha angles.

Conclusions

Beta angle measurement in radial MR images is reproducible and appears to correspond to cartilage damage in the superior regions of the hip. The beta angle may be a useful parameter to assess hip deformity in the followup of SCFE although further confirmation is warranted.     

Are BMPs Involved in Normal Nerve and Following Transection?: A Pilot Study

Bone morphogenic proteins (BMPs) may have neurotrophic functions but there is limited evidence of these functions in the peripheral nervous system. We therefore investigated the expression of BMPs and BMP receptors (BMPRs) in normal and injured peripheral nerves. In 10 of 15 Sprague-Dawley rats, a 3-mm segment of sciatic nerve was resected at the trifurcation in the thigh. One day (n = 5) and 7 days (n = 5) after transection, proximal and distal stumps were removed and immunohistochemically analyzed for BMP-2, -7, BMPR-1A, -1B, and -2. The other five animals served as normal controls. In normal nerves, BMP-2 expression was localized at Ranvier’s node, and BMP-7 and BMPR-1B were expressed in several axon-Schwann cell units, whereas other receptors were not expressed. After nerve transection, BMP-7 expression was upregulated at both proximal and distal stumps along with Schwann cell columns during Wallerian degeneration. BMPRs were also upregulated compared with the normal nerve. The upregulation in BMP expression after nerve transection suggests that BMPs may play a role in the healing response of the peripheral nerve.     

Does Smoking Influence Fusion Rates in Posterior Cervical Arthrodesis With Lateral Mass Instrumentation?

Background  

Smoking is associated with reduced fusion rates after anterior cervical decompression and arthrodesis procedures. Posterior cervical arthrodesis procedures are believed to have a higher fusion rate than anterior procedures.