Relationship Between Revision Rate, Osteoarthritis, and Obesity for ACL Reconstruction: A Nationwide Retrospective Cohort Study.

Background: The long-term goal of anterior cruciate ligament (ACL) reconstruction is to prevent secondary osteoarthritis due to instability. Obesity itself is also a risk factor for osteoarthritis and shows an increase in its incidence, but little is known about the relationship between obesity and the outcome of ACL reconstruction. Purpose/Hypothesis: This study aimed to determine the relationship between the outcome of ACL reconstruction and obesity. It was hypothesized that obesity would be associated with the revision rate of ACL reconstruction and additional surgical treatment for osteoarthritis in patients who undergo ACL reconstruction. Study design: Cohort study; Level of evidence, 3. Methods: Claims and health screening data of the National Health Insurance Service were used to analyze patients who underwent ACL reconstruction between January 1, 2003, and December 31, 2021. The association between obesity and risk of revision ACL reconstruction and additional surgical treatment for osteoarthritis or meniscal lesion was analyzed. Body mass index (BMI) was used to classify patients as underweight (BMI, <18.5), normal weight (BMI, 18.5-24.9), overweight (BMI, 25.0-29.9), obese (BMI, 30.0-39.9), or morbidly obese (BMI, ≥40.0). Multivariable Cox proportional hazards model analysis was conducted. Results: A total of 56,734 patients were included. Of them, 311 (0.5%) patients were underweight, 26,613 (46.9%) were normal weight, 24,372 (43.0%) were overweight, 5324 (9.4%) were obese, and 114 (0.2%) patients were morbidly obese. The underweight group showed a significantly lower risk of revision ACL reconstruction than the normal weight group (hazard ratio [HR], 0.54; 95% CI, 0.31-0.93; P = .0273). However, the overweight, obese, and morbidly obese groups had no significant difference from the normal weight group. The risk of high tibial osteotomy (HTO) or total knee arthroplasty (TKA) was significantly high for the overweight (HR, 1.93; 95% CI, 1.70-2.19; P < .0001) and obese (HR, 2.71; 95% CI, 2.23-3.30; P < .0001) groups. Subgroup analysis performed in patients ≥40 years of age for the risk of HTO showed a significant increased risk in the overweight group (HR, 1.889; 95% CI, 1.56-2.29; P < .0001) and obese group (HR, 2.78; 95% CI, 2.10-3.69; P < .0001). Subgroup analysis performed in patients ≥50 years of age for the risk of TKA also showed a significant increased risk in the overweight group (HR, 2.03; 95% CI, 1.67-2.47; P < .0001) and obese group (HR, 2.53; 95% CI, 1.83-3.50; P < .0001). After adjusting for meniscal injury at index surgery by multivariate regression analysis, 1.87- and 2.75-fold increased risks of HTO were identified for the overweight and obese groups, respectively, for patients aged >40 years. For patients aged >50 years, 2.02-fold and 2.52-fold increased risks of TKA were observed for the overweight and obese groups, respectively. The risk of additional surgery due to the meniscal lesion was high for the overweight (HR, 1.09; 95% CI, 1.03-1.15; P = .002) and obese (HR, 1.10; 95% CI, 1.01-1.21; P = .0351) groups, while no significant difference was found for the underweight and morbidly obese groups. Conclusion: This study highlights that obesity does not increase the revision rate of ACL reconstruction. However, the risk of additional surgical treatment for osteoarthritis and meniscal lesions increased as BMI increased. Further investigation is needed to determine the efficacy of ACL reconstruction for preventing osteoarthritis in obese patients.

An Increase in Medial Joint Space Width After Medial Open-Wedge High Tibial Osteotomy Is Associated With an Increase in the Postoperative Weight-Bearing Line Ratio Rather Than With Cartilage Regeneration: Comparative Analysis of Patients Who Underwent Second-Look Arthroscopic Assessment.

PURPOSE: To investigate relevant factors influencing increases in medial joint space width (JSW) after medial open-wedge high tibial osteotomy (MOWHTO). METHODS: Between January 2010 and December 2018, the electronic medical records of consecutive patients who underwent MOWHTO and subsequent second-look arthroscopic assessment at least 12 months after MOWHTO were retrospectively evaluated. The patients were classified into 2 groups according to changes in the medial JSW of the knee at the time of the second-look operation compared with that at baseline before the initial surgical procedure. Various radiographic parameters, arthroscopic findings, and clinical scores were compared between the groups, and regression analysis was performed to identify factors related to increases in medial JSW. RESULTS: A total of 114 patients were analyzed. In a bivariate analysis, patients who experienced an increase in medial JSW showed a significantly higher postoperative weight-bearing line ratio (WBLR) (P = .008) and a greater proportion of severe preoperative cartilage lesions in the medial compartment of the knee compared with patients with a maintained or reduced medial JSW (P = .035). In terms of clinical scores, patients with an increased medial JSW showed relatively favorable clinical outcomes at the time of the second-look operation. Regression analysis indicated only postoperative WBLR as a relevant factor associated with an increase in medial JSW after MOWHTO (odds ratio, 1.057; P = .01). Additional analysis with patients reclassified according to the postoperative WBLR showed that as the postoperative WBLR increased, the medial JSW increased, without a significant change in the lateral JSW. CONCLUSIONS: An increase in the medial JSW of the knee joint after MOWHTO appears to be associated with an increase in the postoperative WBLR, not with cartilage regeneration. Obtaining adequate correction so that the postoperative WBLR is within 60% to 70% would be desirable in terms of postoperative changes in the medial JSW, as well as clinical outcomes. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Comparison of femoral neck shortening and outcomes between in situ fixation and fixation after reduction for severe valgus-impacted femoral neck fractures.

INTRODUCTION: Severe valgus-impacted femoral neck fractures are associated with femoral neck shortening (FNS). However, no study has focused on the effect of reduction for severe valgus impaction in terms of healing and restoration of the femoral neck length. This study aimed to compare FNS and treatment outcomes of in situ fixation and fixation after reduction for severe valgus-impacted femoral neck fractures in patients aged 65 years or younger. METHODS: This retrospective study included 55 patients who underwent internal fixation with three parallel screws for femoral neck fractures with valgus impaction >15° (AO/OTA classification 31-B1.1) between January 2006 and December 2018. Twenty-eight and 27 patients underwent in situ fixation (in situ group) and fixation after reduction (reduction group), respectively. In the reduction group, reduction using lateral traction with a Schanz pin was performed before internal fixation. Complications such as fixation failure, non-union, and avascular necrosis (AVN), caput-collum-diaphysis (CCD) angle, posterior tilt angle, amount of FNS, and Harris Hip Score (HHS) were compared between the groups. RESULTS: Bone union was achieved in all patients; AVN occurred in two patients in each group. No significant difference was seen in the preoperative characteristics between the groups. The CCD angle at 1 year postoperatively was significantly different between the groups, whereas the posterior tilt angle at 1 year postoperatively was not different. FNS at 1 year postoperatively was significantly lower in the reduction group than in the in situ group. FNS by >5 mm was significantly less frequent in the reduction group than in the in situ group (11% versus 75%). The mean HHS at 1 year and 2 years postoperatively was significantly higher in the reduction group than in the in situ group. FNS and HHS were negatively correlated; the mean HHS was significantly higher in patients with none/mild shortening (<5 mm) than in those with moderate/severe shortening (≥5 mm). CONCLUSION: In patients aged 65 years or younger, internal fixation after reduction for severe valgus-impacted femoral neck fractures is safe and effective for achieving successful bone union and restoring the femoral neck length.

Diagnosis and Operation Results for Chronic Lateral Ankle Instability with Subtle Cavovarus Deformity and a Peek-A-Boo Heel Sign.

Cavovarus deformity is considered an anatomical risk factor for chronic lateral ankle instability (CLAI). However, subtle deformity can be difficult to detect, and its correction is controversial. The current study aimed to evaluate clinical and radiographic outcomes of a modified Broström procedure (MBP) with additional procedures for CLAI with subtle cavovarus deformity and a positive peek-a-boo heel sign. We reviewed the records of 15 patients who underwent MBP with additional procedures for CLAI with a positive peek-a-boo heel sign between August 2009 and April 2015. Consecutive physical and radiographic examinations were performed. The visual analog scale (VAS) for pain, the American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, and the Karlsson-Peterson (KP) ankle score were applied to assess clinical outcomes. Weight bearing radiographs, hindfoot alignment view, and ankle stress radiographs were also examined. The mean follow-up period was 58.5 months. Calcaneal lateral closing wedge osteotomy was performed in seven patients to correct fixed hindfoot varus, and first metatarsal dorsiflexion osteotomy was performed in 11 patients to correct plantarflexion of the first ray. Three patients underwent both procedures. Mean VAS, AOFAS, and KP ankle scores improved significantly (p=0.001), and instability did not recur. Radiographically, all stress parameters improved significantly (p=0.007). Simultaneous correction of a positive peek-a-boo heel sign and cavovarus deformity with MBP for CLAI improves clinical outcomes and prevents recurrent instability. A comprehensive evaluation and cautious approach for subtle cavovarus deformity should be followed when treating patients with CLAI. This trial is registered on Clinical Research Information Service (CRiS, KCT0003287).

Hand grip strength can predict clinical outcomes and risk of falls after decompression and instrumented posterolateral fusion for lumbar spinal stenosis.

BACKGROUND CONTEXT: There has been limited research on the association between hand grip strength (HGS) as one of the diagnostic criteria for sarcopenia and surgical outcomes of lumbar spinal stenosis (LSS). PURPOSE: We aimed to determine the effect of HGS on surgical outcomes and risk of fall in patients with LSS. STUDY DESIGN: This is a retrospective observational study. PATIENT SAMPLE: We included 200 patients who underwent spinal surgery for LSS. OUTCOME MEASURES: We recorded clinical outcome parameters, including Oswestry Disability Index (ODI), Euro-QOL (EQ-5D), and visual analog scale (VAS) scores for back or leg pain. To assess the risk of fall we used HGS and four functional mobility tests (alternative step test, six-meter walk test, timed up and go test, sit-to-stand test). MATERIALS AND METHODS: ODI, EQ-5D, and VAS scores for back and leg pain were assessed preoperatively and 1 year after surgery. The four functional mobility tests were assessed at each time point during the 1-year follow-up period to assess the risk of fall in patients with LSS. We divided the patient cohort according to sex and allocated them into two different groups based on HGS: high HGS (≥26 kg for men, n=26; ≥18 kg for women, n=35), and low HGS (<26 kg for men, n=48; <18 kg for women, n=91). The pre- and postoperative ODI, EQ-5D, and VAS scores for back and leg pain, as well as the functional mobility test results, and demographic data were compared between the two groups using independent t tests. Correlations between HGS and clinical outcome parameters were analyzed using Pearson correlation. RESULTS: In women and men, HGS correlated with the preoperative/postoperative ODI (r1=-0.217/r2=-0.345 in women, and r1=-0.384/r2=-0.411 in men) and EQ-5D scores (r1=0.190/r2=0.309 in women, and r1=0.373/r2=0.467 in men). HGS also correlated with the four postoperative results for the functional mobility tests: alternative step test (r=-0.238 in women, r=-0.431 in men), six-meter walk test (r=-0.232 in women, r=-0.282 in men), timed up and go test (r=-0.285 in women, r=-0.359 in men), and sit-to-stand test (r=-0.238 in women, r=-0.251 in men). The preoperative and postoperative ODI and EQ-5D scores in the high HGS group were superior to those in the low HGS group. Among the four functional mobility tests, preoperative and postoperative six-meter walk test results showed improvements in the high HGS group. CONCLUSIONS: Considering the multifactorial nature of falls, HGS may be a useful surrogate marker for predicting the risk of falls and clinical outcomes in patients with LSS.

Cigarette smoking and knee osteoarthritis in the elderly: Data from the Korean National Health and Nutritional Examination Survey.

BACKGROUND: The relationship between smoking and osteoarthritis (OA) has not been investigated in a large-scale study. The aim of this study was to examine the relationship between smoking and knee OA in the elderly. METHODS: This study included 5117 subjects aged >60 years who responded to questionnaires on their history of smoking and knee OA diagnosed by a physician taken from the Korean National Health and Nutritional Examination Survey (KNHANES-VI) 2013-2015. We classified all 5117 subjects into 2 groups (the OA group and non-OA group) and compared the demographics and characteristics between the 2 groups. A multivariate logistic regression analysis was conducted to investigate the possible association between knee OA and smoking. RESULTS: The prevalence of current smoking in the OA group (5.1%) was significantly lower than in the non-OA group (14.6%; p < 0.001). Furthermore, the proportion of moderate smokers who smoked >10 cigarettes per day or heavy smokers who smoked >20 cigarettes per day was significantly higher in the non-OA group. In the multivariate analysis, current smoking history was a preventative factor for the prevalence of OA in a multivariate model that included age, sex, body mass index, waist circumference (OR: 0.752, 95% CI: 0.571-0.989, p = 0.042). CONCLUSIONS: This large-scale national study highlights an inverse association between smoking and the prevalence of knee OA in the general Korean elder adult population, primarily in males. Further investigation of this relationship between smoking and knee OA is needed to determine smoking's specific mechanism of protection against knee OA.