Kevin Koo

Distal Radius Fractures: An Epidemiological Review

Distal radius fractures are among the most common fractures encountered in clinical practice. Although multiple epidemiological studies have been done in Western populations, there is a lack of data within Asia. Our study aims to fill this knowledge gap.Objective Distal radius fractures are among the most common fractures encountered in clinical practice. Although multiple epidemiological studies have been done in Western populations, there is a lack of data within Asia. Our study aims to fill this knowledge gap. Methods This study included all patients aged 16 years and above with distal radius fractures seen between November 2008 and May 2009 by the Department of Hand and Reconstructive Microsurgery at the Singapore National University Hospital. A retrospective analysis was done. Information captured included clinical data, hand dominance, AO classification of fractures, mechanism of injury, associated injuries as well as treatment modalities. Results Of the 431 fractures, 238 were males, 181 were females. These fractures occur at all ages, peaking at the 50 to 60 years age group. The peak incidence of distal radius fractures in females occurred in the perimenopausal age group, whereas the incidence for males peaked between age of 30 to 50. By AO classification, 53% were type A; 13% were type B and 32% were type C. A fall on the outstretched hand from a standing position is the most common mechanism of injury. As the intensity of the injury mechanism increased, the percentage of type C fractures increased correspondingly. Older patients were more likely to be treated conservatively compared to younger patients. AO severity classification correlated well with the clinicians decision to surgically fix the fracture. No correlation between hand dominancy and fracture site found was found. Conclusion We compared our data with that of previous similar studies, and found similarities as well as differences in results. Nevertheless, the epidemiogical data gathered in this study has added to our knowledge of distal radius fractures in an Asian population.

Effect of Obesity on Outcome of Hallux Valgus Surgery

Background: Obesity is a global epidemic, but its effect on foot and ankle surgeries is not well defined. This study aimed to investigate the influence of obesity on functional outcome scores, incidence of postoperative surgical site infection (SSI), and repeat surgery after hallux valgus (HV) corrective surgery. Methods: Between January 2007 and December 2011, 452 patients who underwent HV corrective surgery at a tertiary hospital were evaluated. They were categorized into 2 groups based on their body mass index (BMI): (1) BMI less than 30 kg/m2 (control); (2) BMI 30 kg/m2 or more (obese). The patients were prospectively followed for 2 years. Results: Patients in the obese group were significantly older by 4 years (95% CI, 1-7 years) (P = .043). The preoperative American Orthopaedic Foot & Ankle Society Hallux Metatarsophalangeal-Interphalangeal (AOFAS Hallux MTP-IP) Scale and Physical Component Score were 6 points (95% CI, 1-11 points) and 3 points (95% CI, 1-6 points) poorer, respectively, in the obese group (P = .014 and P = .032, respectively). However, the Visual Analog Scale, AOFAS Hallux MTP-IP Scale, Physical Component Score, and Mental Component Score were comparable between the 2 groups at 6 months and 2 years of follow-up (all P > .05). Eleven patients (3%) in the control group and 1 patient in the obese group (2%) developed postoperative SSI (P = .777). Nine patients (2%) in the control group and 7 patients in the obese group (14%) required repeat surgery for complications (P < .001). Conclusion: The authors conclude that while it is important to warn obese patients of the significantly higher risk of repeat surgery, these patients should not be excluded from undergoing HV surgery. Level of Evidence: Level III, retrospective comparative series.

Endoscopic Plantar Fasciotomy Improves Early Postoperative Results: A Retrospective Comparison of Outcomes After Endoscopic Versus Open Plantar Fasciotomy

Plantar fasciotomy is offered to patients with recalcitrant plantar fasciitis. Few studies have characterized the functional outcomes over time for the endoscopic approach compared with the open approach. We hypothesized that patients undergoing endoscopic surgery will have better postoperative functional outcomes early in the postoperative period but equivalent long-term outcomes compared with patients undergoing open surgery. We analyzed the prospectively collected data of all patients undergoing plantar fasciotomy at our institution from December 2007 to August 2014. A total of 42 feet of 38 patients were included in the analysis. The clinical data were collected preoperatively and at 3 and 6 months and 1 year. The functional outcomes analyzed included the American Orthopaedic Foot and Ankle Society Ankle-Hindfoot scale, the Medical Outcomes Study, Short-Form, 36-item Health Survey, and patient satisfaction and expectations. Patients undergoing endoscopic surgery had significantly greater American Orthopaedic Foot and Ankle Society Ankle-Hindfoot and SF-36 Health Survey scores and lower pain scores at the 3-month period. They were also significantly more likely to be satisfied with and have had their expectations met by surgery. Compared with the open approach, the patients who had undergone endoscopic plantar fasciotomy experienced significantly greater improvements in the subjective and objective functional outcomes, with less pain and greater satisfaction, and had had their expectations met earlier in the recovery period, with equivalent long-term outcomes, compared with the patients who had undergone open plantar fasciotomy.

Pain Resolution After Hallux Valgus Surgery

Background: Although more than 1500 publications on hallux valgus can be found in the current literature, none of them have reported on the course of pain resolution after hallux valgus surgery. Thus, this study aimed to investigate pain resolution after hallux valgus surgery and to identify predictive factors associated with residual pain at 6 months after surgery. Methods: We prospectively followed up 308 patients who underwent hallux valgus surgery at a tertiary hospital at 6 months and 2 years after surgery. Multivariate logistic regression analysis was performed to evaluate the risk factors associated with residual pain after surgery. Results: Ninety-four patients (31%) had some degree of residual pain at 6 months after surgery. After excluding 4 patients who developed osteoarthritis of the first metatarsophalangeal joint over the next 18 months, 73 of the remaining 90 (81%) experienced improvement in visual analog scale (VAS) by the 2-years follow-up. Their median VAS improved from 4 (interquartile range [IQR] 3, 5) at 6 months to 0 (IQR 0, 3) at 2 years (P < .001). A higher preoperative VAS increased the risk of having persistent pain at 6 months after sugery (odds ratio [OR] 1.388, 95% confidence interval [CI] 1.092, 1.764, P = .007), whereas a higher preoperative Mental Component Score of SF-36 (MCS) reduced this risk (OR 0.952, 95% CI 0.919, 0.987, P = .007). Conclusions: As much as 31% of patients will have residual pain at 6 months after surgery. Preoperative VAS and MCS are predictors for residual pain. However, these patients will continue to improve over the next 18 months, with 71% of them being pain free at 2 years after surgery. Level of Evidence: Level II, prospective comparative study.

Prevalence of Metatarsus Adductus in Symptomatic Hallux Valgus and Its Influence on Functional Outcome

Background: Metatarsus adductus (MA) increases the risk of developing symptomatic hallux valgus (HV). This study aimed to determine the prevalence of MA in patients with symptomatic HV and to evaluate how it affected the functional outcome after scarf osteotomy. Methods: Between January 2007 and June 2012, a total of 206 patients who underwent scarf osteotomy for symptomatic HV at a tertiary hospital were included. The metatarsus adductus angle (MAA) was determined using the Modified Sgarlato method, and these patients were categorized into 2 groups: MA (MAA > 20 degrees); and Control (MAA ≤ 20 degrees). The patients were prospectively followed for 2 years. Results: The prevalence of MA was 33% (68/206) with a mean MAA of 24 ± 4 degrees (range = 20-39). There was a 21 ± 12 degrees and 18 ± 9 degrees improvement in hallux valgus angle for the MA and Control groups, respectively (P = .061), whereas there was a 6 ± 4 degrees and 6 ± 3 degrees improvement in intermetartarsal angle for the MA and Control groups, respectively (P = .475). The visual analog scale, AOFAS Hallux Metatarsophalangeal-Interphalangeal Scale, and Physical and Mental Component Scores were comparable between the 2 groups both preoperatively and at 2 years’ follow-up (all P > .05). Two patients in the control group required revision surgery for recurrence symptomatic HV. Conclusion: The authors conclude that MA did not predispose the patient to poorer functional outcome after scarf osteotomy with the advent of good operative techniques. Level of Evidence: Level II, prospective comparative study.

Two year outcomes of minimally invasive hallux valgus surgery

BACKGROUND We report our experience with the Minimally Invasive Chevron Akin (MICA) technique for correcting hallux valgus, and evaluate its effectiveness and associated complications. METHODS Case series of 13 feet with mild to moderate symptomatic hallux valgus treated surgically from July 2013 to December 2014, with at least 48-months follow-up. Patients were assessed pre-operatively and post-operatively with radiographical measurements (Hallux Valgus Angle (HVA) and Intermetatarsal Angle (IMA)) and clinical scores (American Orthopaedic Foot and Ankle Society (AOFAS), 36-Item Short Form Health Survery (SF-36), Visual Analog Scale (VAS)). RESULTS Mean HVA and IMA decreased from 30.4° and 13.9°-10.9° and 10.2° respectively (p<0.05). The mean AOFAS score improved from an average of 59.0-93.7 (p<0.05). All patients reported a VAS score of 0 post-operatively, and the 4 SF-36 domains improved significantly (p<0.05). CONCLUSIONS The MICA technique is a safe and effective method in the surgical correction of mild to moderate hallux valgus deformity, and continued use is justified.

Minimal Clinically Important Differences for American Orthopaedic Foot & Ankle Society Score in Hallux Valgus Surgery

Background: The American Orthopaedic Foot & Ankle Society (AOFAS) score is one of the most common and adapted outcome scales in hallux valgus surgery. However, AOFAS is predominantly physician based and not patient based. Although it may be straightforward to derive statistical significance, it may not equate to the true subjective benefit of the patient’s experience. There is a paucity of literature defining MCID for AOFAS in hallux valgus surgery although it could have a great impact on the accuracy of analyzing surgical outcomes. Hence, the primary aim of this study was to define the Minimal Clinically Important Difference (MCID) for the AOFAS score in these patients, and the secondary aim was to correlate patients’ demographics to the MCID. Methods: We conducted a retrospective cross-sectional study. A total of 446 patients were reviewed preoperatively and followed up for 2 years. An anchor question was asked 2 years postoperation: “How would you rate the overall results of your treatment for your foot and ankle condition?” (excellent, very good, good, fair, poor, terrible). The MCID was derived using 4 methods, 3 from an anchor-based approach and 1 from a distribution-based approach. Anchor-based approaches were (1) mean difference in 2-year AOFAS scores of patients who answered “good” versus “fair” based on the anchor question; (2) mean change of AOFAS score preoperatively and at 2-year follow-up in patients who answered good; (3) receiver operating characteristic (ROC) curves method, where the area under the curve (AUC) represented the likelihood that the scoring system would accurately discriminate these 2 groups of patients. The distribution-based approach used to calculate MCID was the effect size method. There were 405 (90.8%) females and 41 (9.2%) males. Mean age was 51.2 (standard deviation [SD] = 13) years, mean preoperative BMI was 24.2 (SD = 4.1). Results: Mean preoperative AOFAS score was 55.6 (SD = 16.8), with significant improvement to 85.7 (SD = 14.4) in 2 years (P value < .001). There were no statistical differences between demographics or preoperative AOFAS scores of patients with good versus fair satisfaction levels. At 2 years, patients who had good satisfaction had higher AOFAS scores than fair satisfaction (83.9 vs 78.1, P < .001) and higher mean change (30.2 vs 22.3, P = .015). Mean change in AOFAS score in patients with good satisfaction was 30.2 (SD = 19.8). Mean difference in good versus fair satisfaction was 7.9. Using ROC analysis, the cut-off point is 29.0, with an area under the curve (AUC) of 0.62. Effect size method derived an MCID of 8.4 with a moderate effect size of 0.5. Multiple linear regression demonstrated increasing age (β = −0.129, CI = −0.245, –0.013, P = .030) and higher preoperative AOFAS score (β = −0.874, CI = −0.644, –0.081, P < .001) to significantly decrease the amount of change in the AOFAS score. Conclusion: The MCID of AOFAS score in hallux valgus surgery was 7.9 to 30.2. The MCID can ensure clinical improvement from a patient’s perspective and also aid in interpreting results from clinical trials and other studies. Level of Evidence: Level III, retrospective comparative series.

Radiofrequency microtenotomy is as effective as plantar fasciotomy in the treatment of recalcitrant plantar fasciitis

BACKGROUND Radiofrequency microtenotomy (RM) is effective for treating plantar fasciitis. No studies have compared it to the plantar fasciotomy (PF). We hypothesized that RM is equally effective and provides no additional benefit when performed with PF. METHODS Between 2007 and 2014, all patients who underwent either or both procedures concurrently at our institution were analyzed. Data collected included demographics, SF-36 Health Survey, AOFAS Ankle-Hindfoot Scale, and two questions regarding satisfaction and expectations, all of which were assessed pre-operatively and post-operatively at 6-months and 1-year. ANOVA with Bonferroni correction was used to compare scores at each interval. Logistic regression was used to identify pre-operative factors that predicted for satisfaction and expectations. RESULTS There were no differences in patient outcomes. No pre-operative factors predicted for satisfaction and expectations. CONCLUSIONS RM is as effective as PF in the treatment of plantar fasciitis. Patients who underwent both procedures experienced no benefit and a higher rate of complications.

Clinical and Radiological Outcomes Comparing Percutaneous Chevron-Akin Osteotomies vs Open Scarf-Akin Osteotomies for Hallux Valgus:

Background: Minimally invasive surgeries have gained popularity due to less soft tissue trauma and better wound healing. To date, limited studies have compared the outcomes of percutaneous and open osteotomies. This study aims to investigate the clinical and radiological outcomes of percutaneous chevron-Akin osteotomies vs open scarf–Akin osteotomies at 24-month follow-up. Method: We reviewed a prospectively collected database in a tertiary hospital hallux valgus registry. Twenty-nine feet that underwent a percutaneous technique were matched to 58 feet that underwent open scarf and Akin osteotomies. Clinical outcome measures assessed included visual analog scale (VAS) scores, American Orthopaedic Foot & Ankle Society Hallux Metatarsophalangeal-Interphalangeal score (AOFAS Hallux MTP-IP), and Short Form 36 (SF-36) Health Survey. Radiological outcomes included hallux valgus angle (HVA) and intermetatarsal angle (IMA). All patients were prospectively followed up at 6 and 24 months. Results: Both groups showed comparable clinical and radiological outcomes at the 24-month follow-up. However, the percutaneous group demonstrated less pain in the perioperative period (P < .001). There were significant differences in the change in HVA between the groups but comparable radiological outcomes in IMA at the 24-month follow-up. The percutaneous group demonstrated shorter length of operation (P < .001). There were no complications in the percutaneous group but 3 wound complications in the open group. Conclusions: We conclude that clinical and radiological outcomes of third-generation percutaneous chevron-Akin osteotomies were comparable with open scarf and Akin osteotomies at 24 months but with significantly less perioperative pain, shorter length of operation, and less risk of wound complications. Level of Evidence: Level III, retrospective comparative series.

Genu Recurvatum versus Fixed Flexion after Total Knee Arthroplasty

Background To date, there is no study comparing outcomes between post-total knee replacement genu recurvatum and fixed flexion. This study aims to provide data that will help in deciding which side to err on when neutral extension is not achieved. Methods A prospective cohort study of primary total knee arthroplasties was performed, which compared the 6-month and 2-year clinical outcomes between fixed flexion and genu recurvatum deformities at 6 months. Results At 6 months, knees in genu recurvatum did better than knees in fixed flexion deformity in terms of knee flexion. However, at 2 years, knees in fixed flexion deformity did better in terms of knee scores and showed better improvement in the degree of deformity. Conclusions We conclude that it is better to err on the side of fixed flexion deformity if neutral alignment cannot be achieved.