Nathan A. Jacobson

Implant and Limb Alignment Outcomes for Conventional and Navigated Unicompartmental Knee Arthroplasty

Accurate implant positioning and restoration of lower limb alignment are major requirements for successful long-term results in unicompartmental knee arthroplasty (UKA). Alignment accuracy was compared between navigated-UKA (nUKA) and conventional-UKA (cUKA) groups using a retrospective matched case-control study (n=129, 58 nUKA, 71 cUKA). Mechanical axis (MA), hip-knee-ankle angle (HKA°), coronal implant alignment, and tibial implant posterior slope were measured. No statistically significant difference was observed when comparing MA, HKA° or coronal implant alignment (p>0.05). Statistical significance was seen with tibial component posterior slope (p=0.04, nUKA 4.2°, cUKA 2.9°); and between intra-operative navigationally determined HKA° and post-operative whole-leg standing (WLS) film HKA°. Navigation does not significantly improve UKA alignment compared to conventional methods. Further studies are needed to justify the use of this technology in UKA.

Concussions from 9 youth organized sports: Results from NEISS hospitals over an 11-year time frame, 2002-2012

Background: Youth sports programs are extremely popular throughout the United States, with children starting formal sports participation as young as 4 years. This places children at greater risk for concussions and other trauma. Purpose: To describe the epidemiology of concussions sustained during participation in 9 organized sports prior to participation in high school athletics. Methods: Over an 11-year span from January 2002 to December 2012, the authors reviewed the concussions sustained by athletes aged 4 to 13 years while playing basketball, baseball, football, gymnastics, hockey, lacrosse, soccer, softball, and wrestling, as evaluated in emergency departments (EDs) in the United States and captured by the National Electronic Injury Surveillance System (NEISS) database of the US Consumer Product Safety Commission. Study Design: Descriptive epidemiology study. Results: There were 4864 (national estimate [NE] = 117,845) youth athletes evaluated in NEISS EDs as sustaining concussions from 2002 to 2012. Except for the year 2007, concussion frequencies trended upward throughout the 11-year time frame as well as with increasing age. Loss of consciousness (LOC) occurred in 499 cases (NE, 12,129; 10%). Football had the highest frequency of concussions, with 2013 (NE, 51,220; 41%), followed by basketball, with 977 (NE, 22,099; 20%), and soccer, with 801 (NE, 18,916; 17%). The majority of concussions were treated in the outpatient setting, with 4444 (91.4%) patients being treated and released; 412 (9%) patients required admission and were found to have increased frequencies of LOC (n = 17; 18.0%) compared with LOC in the total group (n = 499, 10%). The total number of player-to-player injury mechanisms mirrored the total number of concussions by year, which increased throughout the 11-year span, except for the year 2007. Subgroup analysis of athletes aged 4 to 7 years demonstrated a difference in the mechanism of injury distribution, with a ball-to-head mechanism increase of 5% from 15% to 20% and a player-to–other object mechanism of injury increase by more than double to 13% compared with the entire cohort over the 11-year time frame. Conclusion: Within the 4- to 13-year age range, there were a significant number of young athletes who presented to EDs with concussion as a result of playing organized sports. The 4- to 7-year age group had a disproportionately higher player-to–other object mechanism of injury. Clinical Relevance: Younger children are more susceptible to long-term sequelae from head injuries, and therefore, improved systems of monitoring for these athletes are required to monitor the patterns of injury, identify risk factors, and develop evidence-based prevention programs.

Concussions From Youth Football Results From NEISS Hospitals Over an 11-Year Time Frame, 2002-2012

Background: Youth football programs across the United States represent an at-risk population of approximately 3.5 million athletes for sports-related concussions. The frequency of concussions in this population is not known. Study Design: Descriptive epidemiology study. Methods: Over an 11-year span from January 2002 to December 2012, the authors reviewed the concussions sustained by athletes aged 5 to 13 years while playing football, as evaluated in emergency departments (EDs) in the United States and captured by the National Electronic Injury Surveillance System (NEISS) database of the US Consumer Product Safety Commission. Results: There were 2028 (national estimate, 49,185) young football players evaluated in NEISS EDs with concussion from 2002 to 2012. There were 1987 (97.9%) males and 41 (2.1%) females, with a mean age of 11.2 years. The total number of concussions reported increased with age and by year. The majority of concussions were treated in the outpatient setting, with 1878 (91.7%) being treated and released. The total number of head-to-head injury mechanisms mirrored the total number of concussions by year, which increased throughout the 11-year span. The total number of players experiencing a loss of consciousness increased throughout the study period but did not match the total number of concussions over the 11-year time period. Fractures occurred in 11 (0.5%) patients, with 2 being severe (1 skull fracture and 1 thoracic compression fracture). Conclusion: Within the 5- to 13-year age range, there were a significant number of young athletes who presented to EDs with concussion as a result of playing organized football. Older children may be at greater risk for sustaining concussions, fractures, and catastrophic injuries while playing football when compared with younger children. Clinical Relevance: Younger children are more susceptible to long-term sequelae from head injuries, and thus, improved monitoring systems for these athletes are needed to assist in monitoring patterns of injury, identifying risk factors, and driving the development of evidence-based prevention programs.

Epidemiology of cheerleading injuries presenting to NEISS hospitals from 2002 to 2007

Background: Cheerleading has developed into a complex sport utilizing aspects of dance, gymnastics/tumbling, single- and multiple-partner stunts, and tosses in complex displays. Stunting and tosses elevates one or multiple participants into the air supported by teammates putting all at significant injury risk. Methods: We reviewed all cheerleading injuries captured by the US Consumer Product Safety Commission National Electronic Injury Surveillance System from 2002 to 2007 that presented to US Emergency Departments and used the new narrative feature added in 2002 to better differentiate injury context and severity. Results: There were 4,245 cases of cheerleaders presenting to National Electronic Injury Surveillance System Emergency Departments from 2002 to 2007 with an average age of 14.6 years, and 96.3% were female. Most of these injuries could be treated as outpatients (97.9%). The extremities were most likely affected, 2,610 (61.5%), with further distribution breakdown as follows: upper extremity 1,339 (31.5%), lower extremity 1,271 (29.9%), head and neck 1,085 (25.6%), trunk 491 (11.6%), and other 48.0 (1.1%). The type of injury sustained in descending order is as follows: sprains/strains 1,871 (44.1%), fractures 709 (16.7%), and contusions 684 (16.1%). The most common mechanism of injury was a collision between two or more cheerleaders (1,242; 29.3% overall), followed by stunting (841; 19.8% overall), tumbling (478, 11.3% overall), and tossing (105, 2.5% overall). Subset analysis was performed on fracture, admit, and severe injury groups. Conclusions: The upper extremity was the most commonly injured part of the body and sustained a significantly greater number of fractures. However, head injuries were more likely to be severe. The value of a more detailed database specific to cheerleading could be invaluable in identifying risk factors and activity-specific injury patterns and facilitate implementing safety measures. Level of Evidence: III.

Unicompartmental knee replacement after high tibial osteotomy: Invalidating a contraindication

The outcome of high tibial osteotomy (HTO) deteriorates with time, and additional procedures may be required. The aim of this study was to compare the clinical and radiological outcomes between unicompartmental knee replacement (UKR) and total knee replacement (TKR) after HTO as well as after primary UKR. A total of 63 patients (63 knees) were studied retrospectively and divided into three groups: UKR after HTO (group A; n = 22), TKR after HTO (group B; n = 18) and primary UKR (group C; n = 22). The Oxford knee score (OKS), Knee Society score (KSS), hip–knee–ankle angles, mechanical axis and patellar height were evaluated pre- and post-operatively. At a mean of 64 months (19 to 180) post-operatively the mean OKS was 43.8 (33 to 49), 43.3 (30 to 48) and 42.5 (29 to 48) for groups A, B and C, respectively (p = 0.73). The mean KSS knee score was 88.8 (54 to 100), 88.11 (51 to 100) and 85.3 (45 to 100) for groups A, B and C, respectively (p = 0.65), and the mean KSS function score was 85.0 (50 to 100) in group A, 85.8 (20 to 100) in group B and 79.3 (50 to 100) in group C (p = 0.48). Radiologically the results were comparable for all groups except for patellar height, with a higher incidence of patella infra following a previous HTO (p = 0.02). Cite this article: Bone Joint J 2013;95-B:1348–53.The outcome of high tibial osteotomy (HTO) deteriorates with time, and additional procedures may be required. The aim of this study was to compare the clinical and radiological outcomes between unicompartmental knee replacement (UKR) and total knee replacement (TKR) after HTO as well as after primary UKR. A total of 63 patients (63 knees) were studied retrospectively and divided into three groups: UKR after HTO (group A; n = 22), TKR after HTO (group B; n = 18) and primary UKR (group C; n = 22). The Oxford knee score (OKS), Knee Society score (KSS), hip-knee-ankle angles, mechanical axis and patellar height were evaluated pre- and post-operatively. At a mean of 64 months (19 to 180) post-operatively the mean OKS was 43.8 (33 to 49), 43.3 (30 to 48) and 42.5 (29 to 48) for groups A, B and C, respectively (p = 0.73). The mean KSS knee score was 88.8 (54 to 100), 88.11 (51 to 100) and 85.3 (45 to 100) for groups A, B and C, respectively (p = 0.65), and the mean KSS function score was 85.0 (50 to 100) in group A, 85.8 (20 to 100) in group B and 79.3 (50 to 100) in group C (p = 0.48). Radiologically the results were comparable for all groups except for patellar height, with a higher incidence of patella infra following a previous HTO (p = 0.02).

Management of Cannulated Screw Failure and Recurrent SCFE Displacement - Case Report

Introduction: SCFE occurs in 10 per 100,000 in some regions of the United States with the incidence continuing to increase. Percutaneous screw fixation is a well-accepted treatment for this disorder for over 20 years but management of complications is not well elucidated in the literature. Case Report: We describe a case where a traumatic unstable SCFE that was initially treated with closed reduction and fixation with a single transphyseal screw went on to hardware failure with recurrence of the deformity. The complication was successfully treated with closed reduction and re-cannulating the fractured screw within the epiphysis and extracting it using a conical extraction screw commonly referred to as an “easy out.” Three trans physeal screws were then placed for improved fixation strength. Follow-up at 9 months demonstrates a fused physis and no signs of avascular necrosis of the femoral head. Conclusion: Percutaneous management of SCFE screw breakage is possible utilizing specialized instruments and a precise and gentle manipulation preventing the need for more invasive treatments with their obligatory potential complications profile.

Septic arthritis of the hip in the setting of hemophagocytic lymphohistiocytosis

Case:A twenty-two-month-old boy with septic hip arthritis had persistent elevated inflammatory markers and daily fevers despite multiple antibiotic regimens and repeated surgical debridements yielding negative cultures. After exhaustive work-up for other infectious, rheumatologic, and immunologic etiologies, he met diagnostic criteria for hemophagocytic lymphohistiocytosis (HLH) and developed cultures positive for fungal hip arthritis. Following treatment for HLH and fungal hip arthritis, he improved and was discharged. Conclusion:No previous report in the literature specifically associates HLH with septic hip arthritis, to our knowledge. Surgeons should suspect underlying immunologic deficiencies and atypical infectious causes of septic arthritis when usual treatment modalities have failed.

Successful two-stage revision of Lactobacillus infection of a total knee arthroplasty and literature review.

BACKGROUND Lactobacillus has been identified as the causative organism in only two total joint arthroplasties: one total hip arthroplasty (THA) and one total knee arthroplasty (TKA). The THA was a litigious case that was treated successfully with a one-stage revision, and the patient with the TKA ultimately required above-knee amputation. We present the first case report of a Lactobacillus infection of a TKA that was treated successfully with a two-stage revision TKA. METHODS Case report and literature review. CASE REPORT While undergoing a revision left TKA for persistent pain, a 55-year-old Caucasian female was found to have a Lactobacillus infection by intra-operative culture. After an extended course of intravenous (IV) antibiotics, the patient underwent a successful two-stage revision of her prosthesis. CONCLUSION Lactobacillus has been appearing more frequently in the literature as a pathogen in patients with compromised immune systems. Orthopedic implant infection with Lactobacillus has only been reported twice, with poorly defined treatment regimens and inconsistent results in both cases. The present report provides orthopedic surgeons and infectious diseases specialists with a treatment algorithm consisting of a two-stage revision of a TKA and a second-line IV antibiotic regimen that may be able to eradicate a Lactobacillus infection of an orthopedic prosthesis with retention of the extremity containing the implant and re-implantation of a functioning prosthesis.

Some Historical Treatments should not be Forgotten: A Review of Cast Wedging and A Trick to Normalize Non-Standardized Digital X-rays.

Introduction: Cast wedging is a simple and reproducible method of manipulating a sub-optimally reduced fracture producing a correction and a final alignment that is amenable to definitive closed treatment. Multiple successful techniques have been previously described in the literature (opening wedge, closing wedge and combination). Technical Note: We present a simple reproducible method of templating and executing a proper cast wedging technique using digital imaging systems that are not controlled for magnification with an illustrative case. Conclusion: Renewed interest in cast wedging can provide a cost effective treatment with proven clinical outcomes in an ever changing and uncertain reimbursement climate.

Unicompartmental knee replacement after high tibial osteotomy

The outcome of high tibial osteotomy (HTO) deteriorates with time, and additional procedures may be required. The aim of this study was to compare the clinical and radiological outcomes between unicompartmental knee replacement (UKR) and total knee replacement (TKR) after HTO as well as after primary UKR. A total of 63 patients (63 knees) were studied retrospectively and divided into three groups: UKR after HTO (group A; n = 22), TKR after HTO (group B; n = 18) and primary UKR (group C; n = 22). The Oxford knee score (OKS), Knee Society score (KSS), hip–knee–ankle angles, mechanical axis and patellar height were evaluated pre- and post-operatively. At a mean of 64 months (19 to 180) post-operatively the mean OKS was 43.8 (33 to 49), 43.3 (30 to 48) and 42.5 (29 to 48) for groups A, B and C, respectively (p = 0.73). The mean KSS knee score was 88.8 (54 to 100), 88.11 (51 to 100) and 85.3 (45 to 100) for groups A, B and C, respectively (p = 0.65), and the mean KSS function score was 85.0 (50 to 100) in group A, 85.8 (20 to 100) in group B and 79.3 (50 to 100) in group C (p = 0.48). Radiologically the results were comparable for all groups except for patellar height, with a higher incidence of patella infra following a previous HTO (p = 0.02). Cite this article: Bone Joint J 2013;95-B:1348–53.The outcome of high tibial osteotomy (HTO) deteriorates with time, and additional procedures may be required. The aim of this study was to compare the clinical and radiological outcomes between unicompartmental knee replacement (UKR) and total knee replacement (TKR) after HTO as well as after primary UKR. A total of 63 patients (63 knees) were studied retrospectively and divided into three groups: UKR after HTO (group A; n = 22), TKR after HTO (group B; n = 18) and primary UKR (group C; n = 22). The Oxford knee score (OKS), Knee Society score (KSS), hip-knee-ankle angles, mechanical axis and patellar height were evaluated pre- and post-operatively. At a mean of 64 months (19 to 180) post-operatively the mean OKS was 43.8 (33 to 49), 43.3 (30 to 48) and 42.5 (29 to 48) for groups A, B and C, respectively (p = 0.73). The mean KSS knee score was 88.8 (54 to 100), 88.11 (51 to 100) and 85.3 (45 to 100) for groups A, B and C, respectively (p = 0.65), and the mean KSS function score was 85.0 (50 to 100) in group A, 85.8 (20 to 100) in group B and 79.3 (50 to 100) in group C (p = 0.48). Radiologically the results were comparable for all groups except for patellar height, with a higher incidence of patella infra following a previous HTO (p = 0.02).