Faculty Bibliography

BACKGROUND:In revision total knee arthroplasty, osteolysis, mechanical abrasion, and infection may leave patellar bone stock severely attenuated with cavitary and/or segmental rim deficiencies that compromise fixation of patellar implant pegs. The purpose of this study was to retrospectively review the use of cortical "rebar" screws to augment cement fixation in revision patelloplasty. METHODS:From 2006 to 2018, dorsal patellar rebar technique was used for patellar reconstruction in 128 of 1037 revision total knee arthroplasty cases (12.3%). Follow-up was achieved with serial radiographs and prospective comparison of Knee Society Scores (KSSs) for clinical outcome. Complications and implant failures requiring reoperation or modified rehabilitation were also assessed. RESULTS:Of the 128 patellar revisions performed using the rebar technique, 69 patients were women and 59 patients were men. The average age of the group was 69.5 years (range, 32-83 years). The mean follow-up of the cohort was 37 months (range, 13-109 months). The most common causes for revision were kinematic conflict, periprosthetic joint infection, and aseptic loosening. The median number of rebar screws used was 5 (range, 1-13). Preoperative KSSs for the study cohort averaged 50 (range, 0-90) At latest follow-up, mean KSS was 85 (range, 54-100). There were 4 patellar-related complications (3.1%) with no implant failures at study conclusion. Retrieval analysis revealed rigid fixation of the reconstructed patellar component in all cases. CONCLUSIONS:Patellar rebar screw augmentation is a useful technique when there are significant cavitary deficiencies and limited segmental rim deficiencies. This technique allows the surgeon to extend indications for patellar revision arthroplasty.

INTRODUCTION/BACKGROUND:Among surgical patients, utilization of institutional-based postacute care (PAC) presents a notable financial burden and is associated with increased risk of complications and mortality rates when compared with discharge home. The purpose of this study was to identify predictors of postdischarge disposition to PAC in geriatric patients after surgical fixation of native hip fractures. METHODS:We have done a query of the American College of Surgeons National Surgical Quality Improvement Program to identify geriatric (≥65 years) patients who sustained surgical femoral neck, intertrochanteric, and subtrochanteric hip fractures in 2016. Multivariate regression was used to compute risk factors for discharge to and prolonged stay (>30 days) in PAC. RESULTS:Eight thousand one hundred thirty-three geriatric hip fracture patients with sufficient follow-up data were identified. Of these, 6,670 patients (82.0%) were initially discharged to PAC after their hip fracture episode of care, and 2,986 patients (36.7%) remained in PAC for >30 days. Age (odds ratio [OR] 1.06 [1.05 to 1.08], P < 0.001), partial (OR 2.41 [1.57 to 3.71], P < 0.001) or total dependence (OR 3.03 [1.92 to 4.46], P < 0.001) for activities of daily living, dementia (OR 1.62 [1.33 to 1.96], P < 0.001), diabetes (OR 1.46 [1.14 to 1.85], P = 0.002), hypertension (OR 1.32 [1.10 to 1.58], P = 0.002), and total hospital length of stay (OR 1.04 [1.01 to 1.08], P = 0.006) were independent risk factors for discharge to PAC. Age (OR 1.05 [1.04 to 1.06], P < 0.001), partial (OR 2.86 [1.93 to 3.79], P < 0.001) or total dependence (OR 3.12 [1.45 to 4.79], P < 0.001) for activities of daily living, American Society of Anesthesiologist's classification (OR 1.27 [1.13 to 1.43], P < 0.001), dementia (OR 1.49 [1.28 to 1.74], P < 0.001), and total hospital length of stay (OR 1.10 [1.08 to 1.13], P < 0.001) were independent risk factors for prolonged PAC stay >30 days. DISCUSSION/CONCLUSIONS:Discharge to PAC is the norm among patients undergoing hip fracture surgery. Provider foreknowledge of risk factors may help improve hip fracture outcomes and decrease healthcare costs.

BACKGROUND:Recent studies have identified vitamin D deficiency (serum 25-hydroxyvitamin D [25(OH)D] < 20 ng/L) as a potentially modifiable risk factor for prosthetic joint infection (PJI) in arthroplasty. The purpose of this study is to determine whether implementation of preoperative 25(OH)D repletion is cost-effective for reducing PJI following total knee arthroplasty (TKA). METHODS:A cost estimation predictive model was generated to determine the utility of both selective and nonselective 25(OH)D repletion in primary TKA to prevent PJI. Input data on the incidence of 25(OH)D deficiency, relative complication rates, and costs of serum 25(OH)D repletion and 2-stage revision for PJI were derived from previously published literature identified using systematic review and publicly available data from Medicare reimbursement schedules. Mean, lower, and upper bounds of 1-year cost savings were computed for nonselective and selective repletion relative to no repletion. RESULTS:Selective preoperative 25(OH)D screening and repletion were projected to result in $1,504,857 (range, $215,084-$4,256,388) in cost savings per 10,000 cases. Nonselective 25(OH)D repletion was projected to result in $1,906,077 (range, $616,304-$4,657,608) in cost savings per 10,000 cases. With univariate adjustment, nonselective repletion is projected to be cost-effective in scenarios where revision for PJI costs ≥$10,636, incidence of deficiency is ≥1.1%, and when repletion has a relative risk reduction ≥4.2%. CONCLUSION:This predictive model supports the potential role of 25(OH)D repletion as a cost-effective mechanism of reducing PJI risk in TKA. Given the low cost of 25(OH)D repletion relative to serum laboratory testing, nonselective repletion appears to be more cost-effective than selective repletion. Further prospective investigation to assess this modifiable risk factor is warranted.

BACKGROUND:The Physician-Payments-Sunshine-Act (PPSA) was introduced in 2010 to provide transparency regarding physician-industry payments by making these payments publicly available. Given potential ethical implications, it is important to understand how these payments are being distributed, particularly as the women orthopaedic workforce increases. The purpose of this study was thus to determine the role of gender and academic affiliation in relation to industry payments within the orthopaedic subspecialties. METHODS:The PPSA website was used to abstract industry payments to Orthopaedic surgeons. The internet was then queried to identify each surgeon's professional listing and gender. Mann-Whitney U, Chi-square tests, and multivariable regression were used to explore the relationships. Significance was set at a value of P < 0.05. RESULTS:In total, 22,352 orthopaedic surgeons were included in the study. Payments were compared between 21,053 men and 1299 women, 2756 academic and 19,596 community surgeons, and across orthopaedic subspecialties. Women surgeons received smaller research and non-research payments than men (both, P < 0.001). There was a larger percentage of women in academics than men (15.9% vs 12.1%, P < 0.001). Subspecialties with a higher percentage of women (Foot & Ankle, Hand, and Pediatrics) were also the subspecialties with the lowest mean industry payments (all P < 0.001). Academic surgeons on average, received larger research and non-research industry payments, than community surgeons (both, P < 0.001). Multivariable linear regression demonstrated that male gender (P = 0.006, P = 0.029), adult reconstruction (both, P < 0.001) and spine (P = 0.008, P < 0.001) subspecialties, and academic rank (both, P < 0.001) were independent predictors of larger industry research and non-research payments. CONCLUSIONS:A large proportion of the US orthopaedic surgeon workforce received industry payments in 2014. Academic surgeons received larger payments than community surgeons. Despite having a larger percentage of surgeons in academia, women surgeons received lower payments than their male counterparts. Women also had a larger representation in the subspecialties with the lowest payments.

PURPOSE OF REVIEW/OBJECTIVE:To review the current basic science and clinical literature on mesenchymal stem cell (MSC) therapy for articular cartilage defects and osteoarthritis of the knee. RECENT FINDINGS/RESULTS:MSCs derived from bone marrow, adipose, and umbilical tissue have the capacity for self-renewal and differentiation into the chondrocyte lineage. In theory, MSC therapy may help restore cartilage focally or diffusely where nascent regenerative potential in the intra-articular environment is limited. Over the last several years, in vitro and animal studies have elucidated the use of MSCs in isolation as injectables, in combination with biological delivery media and scaffolding, and as surgical adjuvants for cartilage regeneration and treatment of knee degenerative conditions. More recently, clinical and translational literature has grown more convincing from early descriptive case series to randomized controlled trials showing promise in efficacy and safety. Studies describing MSC for knee cartilage regeneration applications are numerous and varied in quality. Future research directions should include work on elucidating optimal cell concentration and dosing, as well as standardization in methodology and reporting in prospective trials. Backed by promise from in vitro and animal studies, preliminary clinical evidence on MSC therapy shows promise as a nonoperative therapeutic option or an adjuvant to existing surgical cartilage restoration techniques. While higher quality evidence to support MSC therapy has emerged over the last several years, further refinement of methodology will be necessary to support its routine clinical use.

PURPOSE OF REVIEW/OBJECTIVE:The purpose of the review is to discuss the relevant pathoanatomy, management, complications, and technical considerations for recurrent patellofemoral instability (PFI) in the pediatric population. Special consideration is given to recent literature and management of the patient with repeat instability following surgery. RECENT FINDINGS/RESULTS:Patellar stabilization surgery is in principle dependent upon restoration of normal patellofemoral anatomy and dynamic alignment. Historically, treatment options have been numerous and include extensor mechanism realignment, trochleoplasty, and more recently repair and/or reconstruction of the medial patellofemoral ligament (MPFL) as a dynamic check rein during initial knee flexion. In skeletally immature patients, preference is given to physeal-sparing soft tissue procedures. While medial patellofemoral ligament reconstruction has become a popular option, postoperative failure is a persistent issue with rates ranging from 5 to 30% for PFI surgery in general without any single procedure (e.g., distal realignment, MPFL reconstruction) demonstrating clear superiority. Failure of surgical patellar stabilization is broadly believed to occur for three main reasons: (1) technical failure of the primary stabilization method, (2) unaddressed static and dynamic pathoanatomy during the primary stabilization, and (3) intrinsic risk factors (e.g., collagen disorders, ligamentous laxity). PFI is a common orthopedic condition affecting the pediatric and adolescent population. Treatment of repeat instability following surgery in the PFI patient requires understanding and addressing underlying pathoanatomic risk factors as well as risks and reasons for failure.

OBJECTIVE:To perform a systematic review of clinical outcomes following microfracture (MFX), autologous chondrocyte implantation (ACI), osteochondral allograft transplantation (OCA), and osteochondral autograft transplantation system (OATS) to treat articular cartilage lesions in pediatric and adolescent patients. We sought to compare postoperative improvements for each cartilage repair method to minimal clinically important difference (MCID) thresholds. DESIGN:tests were used to compare mean outcome score improvements to established MCID thresholds. RESULTS:= 0.070) was equivocal. CONCLUSIONS:Outcomes data on cartilage repair in the pediatric and adolescent knee are limited. This review demonstrates that all available procedures provide postoperative improvement above published MCID thresholds for at least one reported clinical pain or functional outcome score.

CASE:A 15-year-old boy with type 1 diabetes mellitus, hypertension, and obesity presented with atraumatic posterior ankle pain and stiffness due to extensive heterotopic ossification (HO) of the Achilles tendon. The ossification was successfully surgically resected and tendon primarily repaired. Wound dehiscence was noted at the first preoperative visit, managed conservatively by local wound care, and healed uneventfully by secondary intention. One-year follow-up showed no recurrence of HO, return to baseline activities, yet low Oxford scores. CONCLUSION:HO of the Achilles tendon is a rare clinical entity. We report an atraumatic case in an adolescent patient with metabolic syndrome, which may demonstrate systemic inflammation because of metabolic syndrome as a risk factor for HO.

BACKGROUND:Total ankle arthroplasty (TAA) offers an effective option for end-stage osteoarthritis. The incidence and preoperative risk factors for early adverse events (AEs) following primary and revision TAA may be useful information for providers. METHODS:A large database was queried from 2010 to 2016 to identify 905 patients of whom 818 underwent primary TAA (90.4%) and 87 underwent revision TAA (9.6%). Data on patient demographics, comorbidities, and hospital length of stay were analyzed as risk factors for reported 30-day AEs. RESULTS:The overall AE rate was 5.5% (50/905) for the entire cohort. AEs occurred more frequently for revision TAA (9/87) than primary TAA (41/818) cases (OR 2.43, p=0.022). Age (OR 1.03, p=0.045), BMI (OR 1.04, p=0.046), and revision TAA (OR 2.56, p=0.002) were independent risk factors for 30-day AEs in multivariate analysis. CONCLUSIONS:Older age, higher BMI, and revision cases are associated with a higher risk of AEs.

Surgical management of patellofemoral instability is technically challenging in skeletally immature patients. Special considerations in this population include activity and sports limitations, recurrence rate, risk of long-term injury to patellofemoral cartilage, and potential for physeal disruption with operative intervention. Numerous procedures have been described to address causative pathoanatomy in the patellofemoral joint, as well as its static and dynamic stabilizers. We describe our technique of combined medial patellofemoral ligament and modified Roux-Goldthwait reconstruction to address both proximal and distal malalignment in a skeletally immature patient with open physes.