Outcomes of Total Ankle Replacement, Arthroscopic Ankle Arthrodesis, and Open Ankle Arthrodesis for Isolated Non-Deformed End-Stage Ankle Arthritis Background: End-stage ankle arthritis is a disabling condition that has a similar effect on morbidity, pain, and loss of function to hip arthritis. We compared clinical outcomes of total ankle replacement (TAR) involving the HINTEGRA prosthesis (Integra LifeSciences), arthroscopic ankle arthrodesis (AAA), and open ankle arthrodesis (OAA) in patients with isolated, non-deformed end-stage ankle arthritis. Methods: Patients ≥18 years old who underwent TAR, AAA, or OAA from 2002 to 2012 with a minimum follow-up of 2 years were retrospectively identified from the Canadian Orthopaedic Foot and Ankle Society (COFAS) Prospective Ankle Reconstruction Database. All patients had symptomatic COFAS Type-1 end-stage ankle arthritis without intra-articular or extra-articular deformity or surrounding joint arthritis. Clinical outcomes included the Ankle Osteoarthritis Scale (AOS) and Short Form-36 (SF-36). Revision was defined as removal of 1 or both metal ankle prosthesis components for TAR and as reoperation for malposition, malunion, or nonunion for AAA and OAA. Results: Analysis included 238 ankles (88 TAR, 50 AAA, and 100 OAA) in 229 patients with a mean follow-up of 43.3 ± 18.5 months. The TAR group had more female patients (55%; p = 0.0318) and a higher mean age (p = 0.0005). Preoperative AOS pain, disability, and total scores were similar for all groups. SF-36 physical and mental component summary scores were similar across groups, both preoperatively and postoperatively. Improvement in AOS total score was significantly larger for TAR (34.4 ± 22.6) and AAA (38.3 ± 23.6) compared with OAA (25.8 ± 25.5; p = 0.005). Improvement in AOS disability score was also significantly larger for TAR (36.7 ± 24.3) and AAA (40.5 ± 26.4) compared with OAA (26.0 ± 26.2; p = 0.0013). However, the greater improvements did not meet the minimal clinically important difference. The TAR group underwent more reoperations than AAA and OAA groups (p < 0.0001). Revision rates were similar for all 3 groups (p = 0.262). Conclusions: AAA and OAA resulted in comparable clinical outcomes to TAR in patients with non-deformed, COFAS Type-1 end-stage ankle arthritis. The rate of component revision in patients who underwent TAR was similar to the rate of revision for patients who underwent AAA or OAA; however, TAR patients underwent a greater number of additional procedures. Overall, AAA and TAR involving the HINTEGRA prosthesis were not significantly different surgical options in terms of short-term outcomes; patients should be counseled regarding higher reoperation rates for TAR. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Minimum 5-Year Follow-up of Mehta Casting to Treat Idiopathic Early-Onset Scoliosis Background: With the exception of Mehta’s 2005 report on her experience treating early-onset scoliosis with serial casting, all subsequent studies have had limited follow-up. This current study sought to assess the results of serial casting at a minimum 5-year follow-up and to identify the predictors of the sustained resolution of scoliosis. Methods: This study is a retrospective review of children treated for idiopathic early-onset scoliosis with serial casting at a children’s hospital between 2001 and 2013 with a minimum 5-year follow-up. A Cobb angle of ≤15° and a decrease in the Cobb angle of >20° at the most recent follow-up were separately assessed. The differences between groups based on these criteria were tested with Student t tests with alpha = 0.05. Results: Fifty-four children were treated during the study period; of these, 38 had at least 5 years of follow-up and comprised the study sample. The mean follow-up (and standard deviation) was 8 ± 2 years (range, 5 to 13 years). The mean patient age at the time of the first cast was 24 ± 15.1 months (range, 9 to 63 months), with a mean Cobb angle of 56.2° ± 20.1° (range, 22° to 109°). Forty-nine percent of children had scoliosis of ≤15° at the time of the most recent follow-up, and 73% of children were improved by at least 20°. Children with ≤15° scoliosis, compared with children with >15° scoliosis, had significantly lower initial Cobb angle (48.2° compared with 63.7°; p = 0.016), supine traction Cobb angle (22.5° compared with 33.2°; p = 0.048), first-in-cast Cobb angle (24.1° compared with 37.6°; p = 0.01), and first-in-cast rib-vertebral angle difference (12.8° compared with 26.2°; p < 0.01). Age at the time of the first cast, initial rib-vertebral angle difference, flexibility, and body mass index were not significantly different (p > 0.05) between the groups. Three children who initially achieved scoliosis of ≤15° after casting substantially relapsed. Conclusions: At a minimum follow-up of 5 years, the initial Cobb angle, first-cast Cobb angle, rib-vertebral angle difference, and traction Cobb angle were all predictive of sustained scoliosis of ≤15°. However, with continued growth, relapse of scoliosis was seen in 3 patients. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Peripheral Nociception Is Associated with Voluntary Activation Deficits and Quadriceps Weakness Following Total Knee Arthroplasty Background: Quadriceps weakness is a hallmark of total knee arthroplasty and is driven by reduced voluntary muscle activation following the surgical procedure. The mechanisms underlying postoperative activation deficits are not well established, although nociception has been implicated via both spinal reflex and supraspinal pathways. The purpose of this study was to assess the role of nociception in postoperative recovery of strength and activation. Methods: A total of 53 participants were assessed prior to total knee arthroplasty and at 6 weeks postoperatively. Quadriceps strength was measured by maximum voluntary isometric contraction, and activation was measured by the doublet interpolation technique. The pressure-pain threshold was used to measure local sensitization (at the knee joint) and systemic sensitization (at the forearm). Changes in outcomes (strength and activation) were regressed against pressure-pain threshold measurements. Mediation analyses were planned for significant associations to investigate whether deficits in voluntary activation were implicated on a causal pathway between pressure-pain threshold measures and postoperative strength loss. Results: Knee pressure-pain threshold measures were significantly associated with reduced voluntary quadriceps activation (beta = −0.04; p = 0.009) and diminished quadriceps strength after total knee arthroplasty (beta = −0.07; p = 0.001). There was also a mediation effect of voluntary activation on the relationship between the knee pressure-pain threshold and quadriceps strength. After correcting for multiple comparisons, relationships between the forearm pressure-pain threshold and strength and activation did not reach significance. Conclusions: The measures of local nociceptor sensitization were related to reduced strength and activation following total knee arthroplasty. This is consistent with a causal pathway linking increased firing of knee joint nociceptors to reduced activation and reduced strength. Future randomized studies should investigate whether peripherally directed pain therapies reduce pain while also promoting the recovery of quadriceps strength via an improved capacity for voluntary activation. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Association Between Race/Ethnicity and Revision Following ACL Reconstruction in a Universally Insured Cohort Background: There have been few large studies involving multiethnic cohorts of patients treated with anterior cruciate ligament reconstruction (ACLR), and therefore, little is known about the role that race/ethnicity may play in the differential risk of undergoing revision surgery following primary ACLR. The purpose of this study was to evaluate whether differences exist by race/ethnicity in the risk of undergoing the elective procedure of aseptic revision in a universally insured cohort of patients who had undergone ACLR. Methods: This was a retrospective cohort study conducted using our integrated health-care system’s ACLR registry and including primary ACLRs from 2008 to 2015. Race/ethnicity was categorized into the following 4 groups: non-Hispanic white, black, Hispanic, and Asian. Multivariable Cox proportional-hazard models were used to evaluate the association between race/ethnicity and revision risk while adjusting for age, sex, highest educational attainment, annual household income, graft type, and geographic region in which the ACLR was performed. Results: Of the 27,258 included patients,13,567 (49.8%) were white, 7,713 (28.3%) were Hispanic, 3,725 (13.7%) were Asian, and 2,253 (8.3%) were black. Asian patients (hazard ratio [HR] = 0.72; 95% confidence interval [CI] = 0.57 to 0.90) and Hispanic patients (HR = 0.83; 95% CI = 0.70 to 0.98) had a lower risk of undergoing revision surgery than did white patients. Within the first 3.5 years postoperatively, we did not observe a difference in revision risk when black patients were compared with white patients (HR = 0.86; 95% CI = 0.64 to 1.14); after 3.5 years postoperatively, black patients had a lower risk of undergoing revision (HR = 0.23; 95% CI = 0.08 to 0.63). Conclusions: In a large, universally insured ACLR cohort with equal access to care, we observed Asian, Hispanic, and black patients to have a similar or lower risk of undergoing elective revision compared with white patients. These findings emphasize the need for additional investigation into barriers to equal access to care. Because of the sensitivity and complexity of race/ethnicity with surgical outcomes, continued assessment into the reasons for the differences observed, as well as any differences in other clinical outcomes, is warranted. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

An Anatomical Study of the Anterosuperior Capsular Attachment Site on the Acetabulum Background: Despite the fact that many surgeons perform partial capsular detachment from the anterosuperior aspect of the acetabulum to correct acetabular deformities during hip arthroscopy, few studies have focused on whether these detachments influence hip joint stability. The aim of this study was to investigate the capsular attachment on the anterosuperior aspect of the acetabulum. We hypothesized that the attachment on the inferior aspect of the anterior inferior iliac spine (AIIS) is wide and fibrocartilaginous and might have a substantial role in hip joint stability. Methods: Fifteen hips from 9 cadavers of Japanese donors were analyzed. Eleven hips were analyzed macroscopically, and the other 4 were analyzed histologically. In all specimens, the 3-dimensional morphology of the acetabulum and AIIS was examined using micro-computed tomography (micro-CT). Results: Macroscopic analysis showed that the widths of the capsular attachments varied according to the location, and the attachment width on the inferior edge of the AIIS was significantly larger than that on the anterosuperior aspect of the acetabulum. Moreover, the capsular attachment on the inferior edge of the AIIS corresponded with the impression, which was identified by micro-CT. Histological analysis revealed that the hip joint capsule on the inferior edge of the AIIS attached to the acetabulum adjacent to the proximal margin of the labrum. In addition, the hip joint capsule attached to the inferior edge of the AIIS via the fibrocartilage. Conclusions: The capsular attachment on the inferior edge of the AIIS was characterized by an osseous impression, large attachment width, and distributed fibrocartilage. Clinical Relevance: It appeared that the capsular attachment on the inferior edge of the AIIS was highly adaptive to mechanical stress, on the basis of its osseous impression, attachment width, and histological features. Anatomical knowledge of the capsular attachment on the inferior edge of the AIIS provides a better understanding of the pathological condition of hip joint instability.

Long-Term Survivorship of Total Hip Arthroplasty with Highly Cross-Linked Polyethylene for Osteonecrosis Background: Osteonecrosis of the hip is the underlying etiology for 3% to 12% of total hip arthroplasties (THAs). Compared with patients who undergo THA because of osteoarthritis, those who do so because of osteonecrosis typically are younger, have a greater number of underlying diagnoses, and have inferior clinical outcomes and implant survivorship. The purpose of this study was to compare the long-term implant survivorship (median follow-up, 10 years), functional outcomes, and radiographic results of contemporary THAs with a highly cross-linked polyethylene (HXLPE) liner between patients with osteonecrosis and those with osteoarthritis. Methods: All patients who underwent primary THA with an HXLPE liner from 1999 to 2007 were identified from our institutional total joint registry. Patients with a primary diagnosis of osteonecrosis were matched 1:1, on the basis of age, sex, and body mass index (BMI), to patients with a diagnosis of osteoarthritis. This resulted in 461 hips in 413 patients with osteonecrosis matched to 461 hips in 427 patients with osteoarthritis (mean age, 59 years; 47% female; and mean BMI, 29 kg/m2). Long-term implant survivorship, patient-reported outcomes, and radiographic findings were compared. In addition, a subgroup analysis of the osteonecrosis group was performed to see whether certain underlying etiologies portended poor outcomes. The median follow-up was 10 years. Results: The 15-year cumulative rates of revision were 6.6% and 4.5% in the osteonecrosis and osteoarthritis groups, respectively (hazard ratio [HR] = 1.8, p = 0.09). The 15-year cumulative rates of any reoperation were 10.5% and 6.4% in the osteonecrosis and osteoarthritis groups, respectively (HR = 2.2, p = 0.008). There were no radiographic signs of component loosening or osteolysis in the entire cohort. Despite a lower median preoperative Harris hip score (HHS) for patients with osteonecrosis, both groups had marked improvements in their scores, which were similar at all time points after surgery. The cumulative rate of reoperations at 15 years was 0% for hips with radiation-induced osteonecrosis, 6.3% for those with alcohol-induced osteonecrosis, 9.0% for those with posttraumatic osteonecrosis, 12.1% for those with steroid-induced osteonecrosis, and 25% for those with idiopathic osteonecrosis. Conclusions: Contemporary THA with an HXLPE liner offers excellent long-term implant survivorship and functional outcomes for patients with osteonecrosis; however, the risk of a reoperation is higher when compared with patients with osteoarthritis. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

“Found Down” Compartment Syndrome: Experience from the Front Lines of the Opioid Epidemic Background: With the worsening of the opioid epidemic, there has been an increasing number of cases in which patients are “found down” following a drug overdose and develop a crush injury resulting in muscle necrosis, rhabdomyolysis, and elevated compartment pressures in a unique presentation of compartment syndrome. The purpose of the present study is to summarize our experience at a trauma center in a region with a high endemic rate of opiate abuse to provide guidance for the management of patients with “found down” compartment syndrome. Methods: We performed a retrospective review of the records of patients who had been found unconscious as the result of overdose, with findings that were concerning for compartment syndrome, and had been managed with fasciotomy or observation at the discretion of the surgeon. The patients were divided into 3 groups based on presentation (partial deficits, complete deficits, or unexaminable), and the operative findings, hospital course, laboratory values, and functional status were compared between the groups. Results: Over 12 years, we identified 30 “found down” patients who had an examination that was concerning for compartment syndrome. Twenty-five patients were managed with fasciotomy; this group required an average of 4.2 operations and had a 20% infection rate and a 12% amputation rate. Lactate, creatine phosphokinase, and creatinine levels typically were elevated but did not correspond with muscle viability or return of function. At the time of initial debridement, 56% of patients had muscle that appeared nonviable, although muscle function returned in 28% of the patients who had questionable viability. Four patients had no motor or neurological function on initial examination, and none had meaningful return of function at the time of the latest follow-up. Of the 10 patients who had partial neurological deficits at the time of presentation and underwent fasciotomy, over half (70%) had some improvement in ultimate function. Conclusions: Patients who are “found down” following an opiate overdose with crush injuries resulting in compartment syndrome have a high surgical complication rate and poor recovery of function. The limited data from the present study suggest that those with absent function at the time of presentation are unlikely to gain function after fasciotomy, and the risk-benefit ratio of fasciotomy in this patient population may be different from that for patients with traumatic compartment syndrome. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Association Between Femoral Component Sagittal Positioning and Anterior Knee Pain in Total Knee Arthroplasty: A 10-Year Case-Control Follow-up Study of a Cruciate-Retaining Single-Radius Design Background: Anterior knee pain is the most common complication of total knee arthroplasty (TKA). The purpose of this study was to assess whether sagittal femoral component position is an independent predictor of anterior knee pain after cruciate-retaining single-radius TKA without routine patellar resurfacing. Methods: A prospective cohort study of 297 cruciate-retaining single-radius TKAs performed in 2006 and 2007 without routine patellar resurfacing identified 73 patients (25%) with anterior knee pain and 89 (30%) with no pain (controls) at 10 years. Patients were assessed preoperatively and at 1, 5, and 10 years postoperatively using patient-reported outcome measures (PROMs), including the Short Form-12 (SF-12), Oxford Knee Score (OKS), and satisfaction and expectation questionnaires. Variables that were assessed as predictors of anterior knee pain included demographic data, the indication for the TKA, early complications, stiffness requiring manipulation under anesthesia, and radiographic criteria (implant alignment, Insall-Salvati ratio, posterior condylar offset ratio, and anterior femoral offset ratio). Results: The 73 patients with anterior knee pain (mean age, 67.0 years [range, 38 to 82 years]; 48 [66%] female) had a mean visual analog scale (VAS) score of 34.3 (range, 5 to 100) compared with 0 for the 89 patients with no pain (mean age, 66.5 years [range, 41 to 82 years]; 60 [67%] female). The patients with anterior knee pain had mean femoral component flexion of −0.6° (95% confidence interval [CI] = −1.5° to 0.3°), which differed significantly from the value for the patients with no pain (1.42° [95% CI = 0.9° to 2.0°]; p < 0.001). The patients with and those without anterior knee pain also differed significantly with regard to the mean anterior femoral offset ratio (17.2% [95% CI = 15.6% to 18.8%] compared with 13.3% [95% CI = 11.1% to 15.5%]; p = 0.005) and the mean medial proximal tibial angle (89.7° [95% CI = 89.2° to 90.1°] compared with 88.9° [95% CI = 88.4° to 89.3°]; p = 0.009). All PROMs were worse in the anterior knee pain group at 10 years (p < 0.05), and the OKSs were worse at 1, 5, and 10 years (p < 0.05). Multivariate analysis confirmed femoral component flexion, the medial proximal tibial angle, and an Insall-Salvati ratio of <0.8 (patella baja) as independent predictors of anterior knee pain (R2 = 0.263). Femoral component extension of ≥0.5° predicted anterior knee pain with 87% sensitivity. Conclusions: In our study, 25% of patients had anterior knee pain at 10 years following a single-radius cruciate-retaining TKA without routine patellar resurfacing. Sagittal plane positioning and alignment of the femoral component were associated with long-term anterior knee pain, with femoral component extension being a major risk factor. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Effect of Plate Design on the Flexor Pollicis Longus Tendon After Volar Locked Plating of Distal Radial Fractures Background: Injury to and rupture of the flexor pollicis longus (FPL) tendon are known complications after volar locking plate fixation for distal radial fractures. Recent investigations have demonstrated that plate positioning contributes to the risk of tendon rupture; however, the impact of plate design has yet to be established. The purpose of this study was to compare FPL tendon-to-plate distance, FPL tendon-plate contact, and sonographic changes in the FPL tendon for 2 volar locking plate designs (ADAPTIVE compared with FPL) using ultrasound examination. Methods: We identified patients who underwent distal radial fracture fixation by 2 fellowship-trained hand surgeons with either standard (ADAPTIVE) or FPL plates. Patients were matched by age, sex, and Soong grade. Enrolled patients returned for a research-related office visit for a clinical examination and bilateral wrist ultrasound. We measured plate-tendon distance, plate-tendon contact, sonographic changes in the FPL tendon, and postoperative radiographic parameters in the operatively treated wrist and the uninjured wrist. Results: Forty patients with Soong grade-1 or 2 plate prominence underwent bilateral wrist ultrasound examination; all of the patients had distal radial fracture fixation, 20 with the standard volar locking plate and 20 with the FPL volar locking plate. Similar proportions of patients with the FPL plate (65%) and those with the standard plate (79%) had plate-tendon contact (p = 0.48); however, the FPL volar locking plate group had significantly less of the FPL tendon in contact with the volar plate than the standard volar locking plate group at wrist extension at both 0° (p < 0.001) and 45° (p < 0.001). There was no difference (p = 0.5) in the proportion of patients with sonographic changes in the FPL tendon between the FPL volar locking plate group (25%) and the standard volar locking plate group (21%). The postoperative volar tilt was significantly lower in patients with FPL plate-tendon contact (p = 0.01) and correlated moderately with the percentage of FPL tendon-plate contact at 0° (r = −0.51; p < 0.001) and 45° (r = −0.53; p < 0.001). There were no cases of tendon rupture in the cohort. Conclusions: We found that the FPL volar locking plate and decreased volar tilt significantly reduced the plate-tendon contact area compared with the standard volar locking plate. In our asymptomatic cohort, we were unable to find a difference in sonographic changes in the FPL tendon. Further studies are needed to determine the clinical importance of decreased tendon-plate contact area seen in modified volar locking plate designs. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of Levels of Evidence.

Patient-Reported Outcome Measures and Health-Related Quality-of-Life Scores of Patients Undergoing Anatomic Total Shoulder Arthroplasty Background: Health-related quality-of-life (HRQoL) scores are required for cost-effectiveness and health-care value analysis. We evaluated HRQoL scores and patient-reported outcome measures (PROMs) in patients with advanced glenohumeral osteoarthritis treated with anatomic total shoulder arthroplasty to establish values of HRQoL scores that can be used for cost-effectiveness and value analysis and to assess relationships between HRQoL scores and shoulder and upper-extremity PROMs. Methods: We analyzed 145 patients (145 shoulders) with glenohumeral osteoarthritis treated with anatomic total shoulder arthroplasty; 93 patients had 1-year follow-up. Preoperative and postoperative functional outcomes were assessed with the Disabilities of the Arm, Shoulder and Hand (DASH) score, the American Shoulder and Elbow Surgeons (ASES) score, the Simple Shoulder Test (SST), and a visual analog scale (VAS) for shoulder pain and function. Health utility was assessed with the EuroQol-5 Dimensions (EQ-5D), Short Form-6 Dimensions (SF-6D), and VAS Quality of Life (VAS QoL). HRQoL score validity was determined through correlations between the PROMs and HRQoL scores. The responsiveness of HRQoL scores was measured through the effect size and the standardized response mean. Results: There were significant improvements in all PROMs and HRQoL scores (p < 0.001) at 1 year after the surgical procedure. The changes in VAS QoL and EQ-5D were significantly correlated (weak to moderate) with the changes in all PROMs except the SST, demonstrating comparably acceptable validity. The VAS QoL had a large effect size (1.833) and standardized response mean (1.603), and the EQ-5D also had a large effect size (1.163) and standardized response mean (1.228), demonstrating responsiveness. The effect sizes of all PROMs were larger than those of the HRQoL scores. The change in SF-6D had only a moderate effect size and standardized response mean and was not significantly correlated with the change in any of the PROMs. Conclusions: PROMs and HRQoL scores are not interchangeable, and studies of the cost-effectiveness and value of shoulder arthroplasty should incorporate both shoulder and upper-extremity PROMs and HRQoL scores. The findings of this study provide data on HRQoL scores that are specific to the treatment of advanced glenohumeral osteoarthritis with anatomic total shoulder replacement and can be used for future cost-effectiveness and value analysis studies. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.