Validity and Reliability of the American Orthopaedic Foot and Ankle Society Score for the English-Literate Singapore Population With Hallux Valgus

BACKGROUND

This study aimed to evaluate the reliability and validity of the American Orthopaedic Foot and Ankle Society Metatarsophalangeal-Interphalangeal (AOFAS MTP-IP) score in patients with hallux valgus in Singapore.

METHOD

A total of 121 English-literate patients with hallux valgus identified between October 2017 and May 2020 were analyzed. Reliability was assessed via Cronbach α. Construct validity was evaluated through 20 a priori hypotheses by correlating the AOFAS MTP-IP score for hallux and lesser toes with other patient-reported outcome measures (PROMs). Standardized response means (SRMs) were calculated to evaluate responsiveness at 6 months postoperative. Structural validity was evaluated via confirmatory factor analysis (CFA) whereby a good fit was indicated when comparative fit index (CFI) is >0.95, Tucker-Lewis index (TLI) is >0.95 and standardized root mean residual (SRMR) is <0.08.

RESULTS

The AOFAS MTP-IP score demonstrated reliability with a Cronbach α of 0.837. Convergent construct validity was confirmed when all a priori hypotheses were fulfilled. Structural validity was established with our AOFAS MTP-IP score model that displayed good fit for a 1-factor structure (CFI = 0.988, TLI = 0.960, SRMR = 0.034). Responsiveness of the AOFAS MTP-IP score for hallux was demonstrated by an SRM score of 1.28.

CONCLUSION

The AOFAS MTP-IP score displayed adequate reliability and validity among English-literate patients in Singapore with an operatively managed hallux valgus.

LEVEL OF EVIDENCE

Level III: Retrospective cohort study.

Can patients with psychological distress achieve comparable functional outcomes and satisfaction after hallux valgus surgery? A 2-year follow-up study

BACKGROUND

This study assessed the influence of preoperative mental health on functional outcomes and satisfaction, and the change in mental health after hallux valgus surgery.

METHODS

383 patients who underwent scarf osteotomy were analyzed. Visual analogue scale (VAS), American Orthopaedic Foot & Ankle Society score (AOFAS) and SF-36 were assessed at 6 months and 2 years. The cohort was stratified into patients with and without psychological distress (i.e. SF-36 Mental Component Summary [MCS] <50 vs ≥50).

RESULTS

After adjusting for demographics and baseline scores, VAS and AOFAS were poorer in the distressed group at 6 months. However, there was no difference in scores at 2 years and a similar proportion of patients were satisfied. SF-36 MCS in distressed patients significantly improved, but remained lower compared to non-distressed patients at follow-up.

CONCLUSIONS

Patients with psychological distress undergoing hallux valgus surgery had poorer short-term outcomes, but these differences resolved at 2 years.

Health-related quality-of-life improvement after hallux valgus corrective surgery

BACKGROUND

Hallux valgus is a common forefoot deformity that affects function of foot and quality of life (QoL). This study aims to identify factors associated with clinically important improvements in QoL after hallux valgus corrective surgery.

METHODS

A retrospective analysis on 591 cases of hallux valgus corrective surgery performed between 2007 and 2013 was conducted. Patients' preoperative and 2-year postoperative Physical Component Score (PCS) and Mental Component Score (MCS) were compared to identify the presence of clinically significant improvements in patient-reported QoL. A multiple logistic regression model was developed through a stepwise variable-selection model building approach. Age, BMI, preoperative patient reported outcome score, PCS, MCS, pain score, gender, side of surgery, type of surgery, and presence of lesser toe deformities or metatarsalgia were considered.

RESULTS

Median PCS significantly improved from 49 to 53 (p < 0.001), and median MCS remained at 56 (p = 0.724). Age, preoperative MCS and PCS were independent predictors for significant improvements of PCS at 2-year postoperatively.

CONCLUSION

Three groups of patients were more likely to have significant QoL improvements after hallux valgus corrective surgery. These were the younger patients, those with better preoperative mental health or those with poorer preoperative physical health.

LEVEL OF EVIDENCE

III.

Distal oblique osteotomy versus cheilectomy for moderate-advanced hallux rigidus: A 2-year propensity-score-matched study

BACKGROUND

The surgical treatment of moderate-advanced hallux rigidus is controversial. Cheilectomy is widely used but has recurrence rates of up to 30%. Dorsal oblique metatarsal osteotomy (DOO) has also shown good results, however, there is no study comparing outcomes of the DOO against cheilectomy.

METHODS

This was a retrospective propensity score matched study based on registry data from a single tertiary institution. Between 2007 and 2017, all patients who had undergone dorsal cheilectomy or DOO for hallux rigidus were included. Patients with previous foot surgery, revision surgeries, and concomitant surgical procedures were excluded. Clinical outcomes, complication rates, revision rates and patient satisfaction were assessed at 2 years postoperatively.

RESULTS

There were 44 patients (34 cheilectomy, 10 DOO). After propensity score matching, 17 cheilectomy and all 10 DOO cases were selected for comparison. Patients in both groups had a significant improvement in visual analogue pain scores (VAS) and AOFAS 1st toe scores 2-years post-operatively (P<0.001) with high levels of post-operative satisfaction (85.1%). Overall there were no statistically significant differences in post-operative scores, improvement in scores, complication rates, revision rates, and levels of patient satisfaction between groups.

CONCLUSIONS

Both the DOO and cheilectomy give similarly good outcomes for moderate-advanced hallux rigidus. Further studies are needed to elucidate differences in indications for each procedure.

Results of Hallux Valgus Surgery in Diabetic Patients With Good Glycemic Control

BACKGROUND

Literature is sparse on whether diabetes affects outcomes of hallux valgus surgery. With the rising global prevalence of diabetes and diabetes being an independent predictor of poorer outcomes, particularly in foot and ankle surgery, we aimed to investigate the impact of diabetes on the outcomes of hallux valgus surgery.

METHODS

We conducted a retrospective comparative cohort study of prospectively collected registry data of 951 feet in 721 patients who underwent surgery for symptomatic hallux valgus between 2007 and 2015 at our institution. All patients with diabetes were identified and matched with patients without diabetes for age, sex, and body mass index in a 1:2 ratio to construct the matched cohorts for analysis. Glycemic control in the diabetic cohort was assessed using preoperative HbA1c. The primary outcome measure was complication rates. Secondary outcomes were (1) deformity correction using the hallux valgus and intermetatarsal angles; (2) patient-reported outcomes using visual analog scale (VAS) for pain, Short Form-36 (SF-36) Physical and Mental Health subscales, and American Orthopaedic Foot & Ankle Society (AOFAS) scores; (3) patient satisfaction; and (4) reoperation rates up to 2 years postoperatively. Forty diabetic patients were identified and matched to 80 nondiabetic patients. Although matching was only performed for age, sex, and body mass index, the diabetic and the nondiabetic cohorts were also similar in hallux valgus severity, preoperative scores, and types of procedures performed.

RESULTS

The mean preoperative HbA1c in our diabetic cohort was 7.1%. Both the diabetic and nondiabetic cohorts showed excellent AOFAS and VAS scores with no differences in degree of deformity correction, complication profiles, reoperation rates, outcome scores, and satisfaction at both 6 months and 2 years postoperatively.

CONCLUSION

We believe stringent patient selection was key to reduced complication rates and good outcomes in diabetic patients. Well-selected diabetic patients remain suitable candidates for hallux valgus surgery.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Clinical outcomes comparing arthroscopic vs open ankle arthrodesis

BACKGROUND

Over the last twenty years, minimally invasive ankle arthrodesis has evolved into a well-tolerated and safe procedure. It has grown in favor to open ankle arthrodesis due to shorter length of stay and fewer complications recorded. This paper aims to compare the clinical outcomes of arthroscopic vs open ankle arthrodesis at 24-months followup.

METHODS

From 2004 to 2015, we reviewed a prospectively collected database in a tertiary hospital foot and ankle registry. 28 feet that underwent arthroscopic ankle arthrodesis were matched to 56 feet that underwent open ankle arthrodesis for age, sex and body mass index (BMI). Visual analogue scale (VAS) scores, American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-hindfoot Scores and Short Form Health Survey (SF-36) were obtained to assess clinical outcomes. These parameters were collected before surgery, at 6months and 24months after surgery.

RESULTS

The arthroscopic group demonstrated significant less pain in the perioperative period (arthroscopic: 1.9±1.2, open: 3.8±1.1, p<0.001) and shorter length of hospitalization stay (arthroscopic: 2.1±0.7 open: 3.5±1.7, p<0.001). Patients who underwent arthroscopic ankle arthrodesis also reported a higher SF-36 score on physical functioning at 6months (arthroscopic: 58.4±27.1, open: 47.1±24.0, p<0.05) and higher AOFAS Ankle-hindfoot Scale score at 24-months (arthroscopic: 78.9±18.9, open: 68.9±24.7, p<0.05). There were no postoperative complications in the arthroscopic group but 11 in the open group, including 9 which required followup operations. There was no significant difference in length of operative procedure between both groups.

CONCLUSIONS

We conclude that the arthroscopic group displayed better clinical outcomes compared to the open group at the 24months followup. The advantages of arthroscopic ankle arthrodesis include significantly less perioperative pain, higher AOFAS Ankle-hindfoot scores at 24months, shorter length of stay, fewer postoperative complications and followup operations.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

Effect of Severity of Deformity on Clinical Outcomes of Scarf Osteotomies

BACKGROUND

Literature is sparse on whether severity of hallux valgus affects outcomes of surgery. We thus aimed to evaluate the impact of hallux valgus severity on the clinical outcomes of surgery.

METHODS

83 consecutive scarf osteotomies performed by a single surgeon for symptomatic hallux valgus between 2007 and 2011 were divided into 3 groups (mild, moderate, and severe) based on severity of their preoperative hallux valgus using the hallux valgus and intermetatarsal angles. Outcomes were assessed using the visual analog scale (VAS) for pain, 36-Item Short Form Health Survey physical functioning (SFPF) and mental health (SFMH) subscales, and American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores. These were assessed preoperatively and at 6 months and 2 years postoperatively. Patient satisfaction was assessed at 6 months and 2 years postoperatively. Eleven (13.2%), 54 (65.1%), and 18 (21.7%) feet were in the mild, moderate, and severe groups, respectively.

RESULTS

There was no difference in preoperative VAS, SFPF, SFMH and AOFAS scores between the groups except for AOFAS scores for the second toe, which were poorer with increasing hallux valgus. Postoperatively, there was improvement across all outcome scores. VAS and AOFAS showed excellent scores, and patient satisfaction was high across all 3 groups (88.9%, 89.4%, and 86.7%). The severe group had slightly lower SFPF scores at 6 months (mild, 81.1; moderate, 84.0; severe, 74.3; P = .031) and 2 years postoperatively (mild, 93.4; moderate, 89.7; severe, 76.4; P = .005), and slightly poorer second toe scores for VAS (mild, 0.0; moderate, 0.1; severe, 1.2; P = .017) and AOFAS (mild, 94.7; moderate, 93.5; severe, 83.4; P = .043) at 2 years postoperatively. All other scores including patient satisfaction showed no between-group differences. Complication and revision rates between the groups were similar.

CONCLUSION

Surgery for symptomatic hallux valgus lead to excellent outcomes and high patient satisfaction regardless of severity of deformity.

LEVEL OF EVIDENCE

Level III, comparative series.

The effect of gender in hallux valgus surgery. A propensity score matched study

BACKGROUND

Males and females who undergo hallux valgus (HV) surgery have different expectations.

METHODS

Data from 439 patients, with 26 males, were prospectively collected between 2007-2015. Propensity score matching (PSM) of one male to two females was performed using logistic regression of six variables to minimize selection bias. Hallux visual analogue scale (VAS) scores, AOFAS scores, SF-36, satisfaction and expectation scores were analysed at two years.

RESULTS

There were no significant differences in patient demographics after PSM. At two years, males and females attained similar VAS and AOFAS scores but males had significantly lower SF-36 general health score (males 68.7, females 79.3). 26.9% of males and 21.2% of females were not satisfied after surgery. Higher proportion of males did not have their expectations fulfilled (males 19.2%, females 5.8%) although this was not statistically significant.

CONCLUSIONS

Both genders attain similar outcome at two years. There is a trend towards lower expectation fulfilment in males after surgery.

Lateral versus central tendon-splitting approach to insertional Achilles tendinopathy: a retrospective study

INTRODUCTION

This study aimed to compare operative outcomes between the lateral approach (LA) and the central approach (CA) to insertional Achilles tendinopathy (IAT).

METHODS

We retrospectively reviewed patients who underwent surgical treatment for IAT using the LA or CA. Patients' demographic data, postoperative complications and satisfaction rate were reviewed. Clinical outcomes were prospectively assessed preoperatively, at three months postoperatively and at the last visit, including patients' visual analogue scale (VAS) scores for pain, American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale scores and 36-item Short Form Health Survey (SF-36) scores.

RESULTS

There were 39 patients in the LA group and 32 in the CA group. In each group, average VAS and AOFAS Scale scores improved significantly. SF-36 scores improved in most parameters. No significant difference in baseline score; average AOFAS Scale score at each visit; and mean VAS score preoperatively and at last visit; satisfaction rate; and overall complication rate were observed between the groups. The mean VAS score in the LA group at postoperative three months was significantly lower than that in the CA group (2.7 ± 2.5 vs. 4.4 ± 3.0; p = 0.016). There were significantly more cases of delayed wound healing in the LA group than in the CA group (2.6% vs. 15.6%; p = 0.049).

CONCLUSION

Both approaches had comparable outcomes for IAT in terms of functional improvement, pain relief, overall enhancement of patients' health condition and overall postoperative complication rate. The LA provided better short-term pain relief and reduced delayed wound healing compared with the CA.

Early Functional, Radiological Outcomes and Satisfaction Rates of Total Ankle Arthroplasty in an Asian Population

BACKGROUND

Few studies have outlined the outcomes and complications in Asians undergoing total ankle arthroplasty. This study reports the functional, radiological outcomes and satisfaction rates in our Asian population.

METHODS

Patients who underwent primary total ankle arthroplasty from 2007 to 2013 were recruited. Outcomes evaluated were the AOFAS Ankle-Hindfoot Score (AHS), Visual Analogue Scale (VAS), and the Short Form 36 (SF-36)questionnaire. Outcome scores were collected prospectively up to 2 years. Patient satisfaction was evaluated on a 6-point scale based on North American Spine Society Low Back Pain Instrument and classified as satisfied or unsatisfied.

RESULTS

Forty-one patients underwent primary total ankle arthroplasty. All patients experienced improvements in AHS, VAS, and Mental Component Summary score of the SF-36 at both 6-month and 2-year postoperative interval. The mean AHS score improved from 35 ± 19 points preoperatively to 64 ± 24 at 6 months (P<.001) and 72 ± 26 at 24 months (P <.001). VAS scores improved from 7 ± 2 preoperatively to 3 ± 3 (P < .001) at 6 and 24 months. The Physical Component Summary (PCS) of the SF-36 has an established minimum clinically important difference (MCID) of 5. The mean improvement in PCS in our cohort met this MCID for the PCS; 63% and 71% of patients were satisfied with the procedure at 6 months and 2 years postoperatively, respectively. Revision rate in this series was 9.7%.

CONCLUSION

Total ankle arthroplasty has good patient satisfaction rates, with favorable early clinical outcome in Asian patients.

LEVELS OF EVIDENCE

Therapeutic, Level II.

Clinical and radiological outcomes of concomitant endoscopic gastrocnemius release with scarf osteotomy

BACKGROUND

Studies showed patients with hallux valgus also have tight gastrocnemius concomitantly. This study aims to investigate (1) prevalence of tight gastrocnemius in symptomatic hallux valgus (2) clinical and radiological outcomes of concomitant endoscopic gastrocnemius release with scarf osteotomy.

METHODS

Between January 2011 to December 2013, 224 patients underwent hallux valgus surgery were evaluated. They were categorized into 2 groups: scarf osteotomy (n=195), scarf and endoscopic gastrocnemius release (combine, n=29). Clinical outcome measures assessed included VAS, AOFAS Hallux MTP-IP and SF-36 scores. Radiological outcomes included HVA, IMA, HVI and TSP. All patients were prospectively followed up for 6 and 24 months.

RESULTS

The prevalence of ipsilateral gastrocnemius tightness in symptomatic hallux valgus is 12.9%. No significant difference in preoperative clinical outcomes between the two groups (all p>.05). Although AOFAS was 6±2 points poorer in the combine group compared to the scarf group at 6 months follow up (p=0.021), at 24 months, all clinical outcomes were comparable between the two groups (all p>0.05). Significant difference in the HVA change between the groups were observed but comparable radiological outcomes in IMA, TSP and HVI at 24 months follow up.

CONCLUSIONS

We conclude clinical and radiological outcomes of concomitant endoscopic gastrocnemius release and scarf osteotomy are comparable with scarf osteotomy alone at 24 months.

Surgical Correction of Haglund's Triad Using a Central Tendon-Splitting Approach: A Retrospective Outcomes Study

We evaluated the surgical outcomes of Haglund's triad using a central tendon-splitting approach, with Achilles tendon partial detachment and debridement, excision of the retrocalcaneal bursa, resection of Haglund's prominence, and reattachment of the Achilles tendon. The medical records of 22 patients (22 heels) who had undergone surgical correction of Haglund's triad from January 2010 to December 2015 were reviewed retrospectively. The visual analog scale pain score, American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scale score, and 36-item Short-Form Health Survey physical and mental component scores were prospectively collected preoperatively, 6 months postoperatively, and at the last visit. The scores of a subjective question involving satisfaction were prospectively collected at the last visit. Possible risk factors were also evaluated. We reviewed the data from 12 females and 10 males, with the mean age of 59.2 ± 7.3 years and a mean follow-up duration of 15.1 ± 4.6 months. Significant improvement was found in the mean visual analog scale pain score, average American Orthopaedic Foot and Ankle Society Ankle-Hindfoot scale score, and 36-item Short-Form Health Survey physical component scale score. The overall satisfaction rate was 77.3% (17 of 22). Postoperative complications included 2 cases of delayed wound healing and 1 case of sensation loss over the heel wound. No Achilles tendon rupture or wound infection developed. Gender and body mass index did not affect the surgical outcomes. The surgical technique we used for Haglund's triad provided effective pain relief, function improvement, and overall enhancement of patients' health condition. More research is required to further evaluate the outcomes of our surgical approach to treat Haglund's triad and the possible risk factors.

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.

Endoscopic Plantar Fasciotomy vs Open Radiofrequency Microtenotomy for Recalcitrant Plantar Fasciitis

BACKGROUND

Although usually self-limiting, around 10% of patients develop recalcitrant plantar fasciitis despite conservative treatment. In such cases, operative intervention can be offered. Traditionally, plantar fasciotomy has been the treatment of choice, but recently, there has been a push for more minimally invasive approaches. Radiofrequency microtenotomy has also been increasingly used as a treatment option. In this study, we compare the outcomes of endoscopic plantar fasciotomy and open radiofrequency microtenotomy.

METHODS

Patients treated in our institution with either procedure between 2007 and 2015 were included and interviewed at baseline and 3 months, 6 months, and 12 months postoperatively using the American Orthopaedic Foot & Ankle Society (AOFAS) and 36-item Medical Outcomes Short Form (SF-36) questionnaires. They were asked questions to evaluate their expectation and satisfaction postoperatively. Demographic and clinicopathological data were prospectively collected from clinical charts and electronic records.

RESULTS

There was no difference in either treatment arms preoperatively and an overall improvement in all functional outcomes postoperatively. However, patients who had endoscopic plantar fasciotomy fared better at 3 months compared to patients who underwent open microtenotomy with the visual analog score component of the AOFAS hindfoot score (HINDVAS) and the social functioning and role-functioning-emotional reaching statistical significance ( P = .027, P = .03, and P = .03, respectively). There was no difference in functional outcomes at 6 or 12 months postoperatively.

CONCLUSION

Endoscopic plantar fasciotomy was associated with an earlier improvement in functional outcome in our study. However, both treatments had equivalent outcomes at 1-year follow-up, suggesting that either method is reasonable in the treatment of chronic plantar fasciitis.

LEVEL OF EVIDENCE

Level III, comparative study.

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.

Incidence of postoperative wound infections after open tendo Achilles repairs

INTRODUCTION

Tendo Achilles (TA), which is the confluence of the gastrocnemius and soleus muscles, is one of the most commonly injured tendons. The surgical repair of TA ruptures is associated with a significant risk of infection. This study examined several factors (i.e. gender, age, body mass index, history of diabetes mellitus, steroid use, acute or chronic TA injuries, type of surgical incision and type of sutures used) that may be associated with postoperative wound infection after open TA repair.

METHODS

This was a retrospective study involving 60 patients who underwent open TA repair over an 18-month period. Patients who had prior TA surgery or open TA injuries, or who needed soft tissues flaps were excluded.

RESULTS

Among the patients, 7 (11.7%) developed superficial wound infections that were successfully treated with oral antibiotics, while 3 (5.0%) developed deep wound infections that required at least one debridement procedure. No significant association was found between the risk of postoperative wound infection and gender, age, the presence of diabetes mellitus, acute or chronic ruptures, site of surgical incision and type of deep or superficial sutures used.

CONCLUSION

While diabetes mellitus and age did not appear to be associated with postoperative wound infections after open TA repair, obese patients were found to be two times more likely to develop a wound infection than normal-weight patients. The incidence of superficial wound infections in this study was similar to previously published results (11.7% vs. 8.2%-14.6%), but the incidence of deep infections was higher (5% vs. 1%-2%).

Tibial Sesamoid Position Influence on Functional Outcome and Satisfaction After Hallux Valgus Surgery

BACKGROUND

During hallux valgus surgery, the abnormal position of the first metatarsal bone relative to the sesamoids is addressed. Our study aimed to investigate the influence of postoperative tibial sesamoid position (TSP) on functional outcome and patient satisfaction after hallux valgus surgery.

METHODS

Between February 2007 and November 2011, 250 patients who underwent hallux valgus surgery at our tertiary hospital were followed for 2 years after surgery. They were categorized into 2 groups based on Hardy and Clapham's TSP classification, recorded on postoperative weight-bearing anteroposterior (AP) radiographs: (1) normal (grades I-IV) and (2) outliers (grades V-VII).

RESULTS

The mode TSP improved from grade VII preoperatively to grade IV postoperatively (P < .001). The visual analog scale for pain was 1 (95% CI 0, 1) point better in the normal group compared to the outlier group at 2 years after surgery (P = .050), whereas the American Orthopaedic Foot & Ankle Society Hallux Metatarsophalangeal-Interphalangeal Scale was 6 (95% CI 2, 11) points higher in the normal group (P = .009). Patients in the outlier group were also more likely to be dissatisfied with the surgery performed when compared to the normal group (OR 3.881, 95% CI 1.689, 8.920, P = .001).

CONCLUSION

We recommend correcting the TSP to grade of IV or less to improve functional outcome and satisfaction after hallux valgus surgery.

LEVEL OF EVIDENCE

Level III, retrospective comparative series.

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.

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/m(2) (control); (2) BMI 30 kg/m(2) 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.

Can tranexamic acid and hydrogen peroxide reduce blood loss in cemented total knee arthroplasty?

INTRODUCTION

The use of tourniquet in total knee arthroplasty (TKA) has resulted in negligible intra-operative blood loss but notable post-operative blood loss, creating the ideal scenario for using topical haemostatic agents intra-operatively. Recently, medical adjuvants including tranexamic acid (TXA) and hydrogen peroxide (H2O2) have been introduced. The aim of this study was to evaluate the effectiveness of intra-articular TXA and H2O2 in reducing blood loss during TKA.

MATERIALS AND METHODS

Fifty patients, who underwent a primary TKA with 1,500 mg of intra-articular TXA between May 2011 and December 2011, were compared with two matching cohorts of 50 patients each who underwent TKA with 100 ml of 3 % H2O2 wash and TKA without any TXA or H2O2. All surgeries were performed by two senior surgeons. The total blood loss was calculated by the hemoglobin balance method.

RESULTS

The pre-operative serum hemoglobin levels were 13.1 ± 1.3, 13.1 ± 1.3 and 13.0 ± 1.2 g/dl (p > 0.05); while the drop in serum hemoglobin levels post-operatively was 2.0 ± 0.7, 2.4 ± 0.9 and 2.7 ± 0.8 g/dl for the TXA, H2O2 and Control groups, respectively (p < 0.001). The total amount of blood loss was 596 ± 449, 710 ± 279 and 760 ± 228 ml, respectively (p = 0.046). There was no difference in the duration of surgery between the three groups (p > 0.05).

CONCLUSIONS

This study showed that intra-articular TXA reduced blood loss during TKA without significantly increasing the duration of surgery. We cannot justify H2O2 wash as an alternative to intra-articular TXA to reduce blood loss during TKA.

Tibiotalocalcaneal arthrodesis in a Singaporean hospital

PURPOSE

To report 18 patients who underwent tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail or cannulated screws.

METHODS

10 men and 8 women (19 ankles) aged 36 to 70 (mean, 52) years underwent tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail (n=13) or cannulated screws (n=6). Indications for arthrodesis were severe cavovarus deformity secondary to polio or charcot-marie-tooth disease (n=7), severe osteoarthritis in the ankle and subtalar joints (n=6), Charcot joint deformity (n=3), failed fusion procedures (n=2), and foot drop secondary to T12 tumour surgery (n=1). The visual analogue score (VAS) for pain was assessed, as were the American Orthopaedic Foot and Ankle Society (AOFAS) scores (for subjective and objective pain, function, and stability of the ankle), short form 36 (SF-36), and patient expectation and satisfaction scores.

RESULTS

The mean follow-up period was 35.6 (range, 11-144) months. 13 of 18 patients returned for assessment of scores. 18 of the 19 ankles achieved fusion after a mean period of 5.9 (range, 3-11) months. The mean VAS scores for pain, AOFAS scores, and SF-36 scores all improved. 11 patients had good-to-excellent satisfaction and expectation scores. Two patients had severe wound infections and underwent implant removal (after bone union), debridement, and intravenous antibiotic therapy. Two other patients had superficial wound infections. One patient with retrograde intramedullary nailing had a pseudoarthrosis and underwent implant removal, redebridement, re-autografting, and cannulated screw fixation. Fusion was achieved subsequently.

CONCLUSION

Tibiotalocalcaneal arthrodesis improved the pain score and quality of life, despite a high risk of complications.

Chronic Achilles Tendon Rupture Treated with Two Turndown Flaps and Flexor Hallucis Longus Augmentation – Two-year Clinical Outcome

Introduction: Both conservative and operative management have been described in the literature for the management of chronic Achilles tendon ruptures with surgical management generally having more favourable results. In our institution, the favoured reconstructive technique was the use of 2 turndown tendon flaps fashioned from the proximal Achilles tendon augmented by a teno-myodesis of the flexor hallucis longus. The purpose of this study was to assess the clinical outcome of all patients who underwent this procedure. Materials and Methods: From the records, a total of 9 patients underwent the above-mentioned procedure of whom 6 patients had complete data collection sets [including SF-36, Visual Analogue Scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scores, ankle range of motion (ROM), presence of residual symptoms and complications] at 2 years of follow-up. Results: Our results showed an average AOFAS Ankle-Hindfoot score of 94.2, VAS of 0 in all but 1 patient, and generally high scores (75-96) in all 8 domains of the SF-36 questionnaire. Patient satisfaction was also rated to be high from the surgical procedure. Conclusion: We submit that the procedure adopted at our institution is able to reproduce satisfactory results with low morbidity in patients with this challenging condition. Key words: Ankle, Autograft, Reconstruction

Chronic Achilles tendon rupture treated with two turndown flaps and flexor hallucis longus augmentation - two-year clinical outcome

INTRODUCTION

Both conservative and operative management have been described in the literature for the management of chronic Achilles tendon ruptures with surgical management generally having more favourable results. In our institution, the favoured reconstructive technique was the use of 2 turndown tendon fl aps fashioned from the proximal Achilles tendon augmented by a tenomyodesis of the flexor hallucis longus. The purpose of this study was to assess the clinical outcome of all patients who underwent this procedure.

MATERIALS AND METHODS

From the records, a total of 9 patients underwent the above-mentioned procedure of whom 6 patients had complete data collection sets [including SF-36, Visual Analogue Scale (VAS), American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot scores, ankle range of motion (ROM), presence of residual symptoms and complications] at 2 years of follow-up.

RESULTS

Our results showed an average AOFAS Ankle-Hindfoot score of 94.2, VAS of 0 in all but 1 patient, and generally high scores (75-96) in all 8 domains of the SF-36 questionnaire. Patient satisfaction was also rated to be high from the surgical procedure.

CONCLUSION

We submit that the procedure adopted at our institution is able to reproduce satisfactory results with low morbidity in patients with this challenging condition.

Radiofrequency coblation for chronic foot and ankle tendinosis

PURPOSE

To evaluate outcomes of radiofrequency coblation for chronic tendinosis of the foot and ankle tendons.

METHODS

Records of 7 men and 8 women (16 feet) aged 27 to 65 years who underwent radiofrequency coblation for chronic tendinosis (combined with other procedures for other pathology) of the Achilles, posterior tibial, and peroneal tendons were retrospectively reviewed. The visual analogue scale (VAS) for pain status, the Short Form (SF-36) questionnaire for quality of life, and the American Orthopaedic Foot and Ankle Society (AOFAS) scores for functional status of the patients were determined pre- and post-operatively.

RESULTS

All patients reported significant reduction in pain at 3 months, with more than 63% attaining VAS scores of 0 at 6 months. AOFAS scores were significantly improved at both 3 and 6 months. Most components of SF-36 scores improved at 6 months except those for general health and role emotional; only those for bodily pain improved significantly. At postoperative month 3 and 6 respectively, 93 and 100% of the patients had their expectations met, whereas 93 and 88% had good-to-excellent satisfaction. There were no major complications.

CONCLUSIONS

Radiofrequency coblation for chronic tendinosis of the foot and ankle achieves good short-term outcomes and pain relief. It may be combined with other procedures for maximal benefit.

Salvage arthrodesis for fracture-dislocation of the cuneonavicular and calcaneocuboid joints: a case report

We present a 22-year-old man with dislocation of both the calcaneocuboid and cuneonavicular joints and fractures of the calcaneum and navicular of the right foot. The joints were reduced with percutaneous Kirschner wires, but the disrupted dorsal cuneonavicular ligaments were left unrepaired. Reduction was suboptimal and the joints were subluxed resulting in disabling arthralgia. Six months later, he underwent salvage arthrodesis of the subluxed calcaneocuboid and cuneonavicular joints. At 24-month follow-up, the patient had returned to work and remained pain-free when walking, with good fusion of both joints. Early anatomic reduction, stable fixation, and ligament reconstruction are essential for a good outcome. Arthrodesis is indicated when subluxation and posttraumatic arthritis are present. Primary arthrodesis is a viable option for severe midfoot fracture-dislocations, because it facilitates rehabilitation and functional recovery, and obviates the need for a secondary arthrodesis should arthritis arise.

The use of computer navigation in performing minimally invasive surgery for intertrochanteric hip fractures--The experience in Singapore

OBJECTIVE

Intertrochanteric hip fractures are very common and early mobilisation correlates with a better outcome. The ideal surgical procedure should protect the soft tissue envelope, thereby preserving blood supply and reducing blood loss. Furthermore, occupational exposure to fluoroscopy that is used in hip fracture fixation remains a concern amongst orthopaedic surgeons. Computer-aided surgery can help to reduce reliance on fluoroscopy. We therefore combined the principles of minimally invasive plate osteosynthesis (MIPO) and computer navigation to describe a new procedure. We also present our results using this technique of minimally invasive computer-navigated dynamic hip screw fixation (navMIS-DHS), and compare it to computer-navigated open DHS fixation (nav-DHS) and to conventional open DHS fixation (conv-DHS).

MATERIALS AND METHODS

This paper has three parts. In the first part, we describe the procedure of navMIS-DHS in detail. In the second part, we present our initial retrospective pilot series of 35 cases. Amongst them we performed 5 navMIS-DHS, 3 nav-DHS and 27 conv-DHS. There were also two cases of conv-DHS deliberately performed with a mini-incision in an attempt to see if we could duplicate the 5 cm incision that we achieved with navMIS-DHS. All patients were followed up for a minimum of 6 months. In the third part, we performed a single surgeon prospective evaluation of navMIS-DHS versus conv-DHS involving 43 fractures in two arms.

RESULTS

We were able to achieve reduction in fluoroscopy time. There was also reduction in opiate requirement post-operatively in the minimally invasive procedure. The incision sizes were also smaller. The prospective study also showed less wound-related complications in navMIS-DHS and a shorter time to ambulation. Implant positions were acceptable but we have also described how it may be improved.

CONCLUSIONS

Navigated MIS-DHS, by virtue of less pain, better healing, earlier rehabilitation and potentially shorter hospital stay, would benefit both the patients and reduce the economic strain on the health care system. It is a safe and reproducible procedure. Technical difficulties are present and these need to be addressed with further modifications of technique, and instrumentation.

Femoral shaft fracture in a hip arthrodesis: two cases of retrograde interlocking nailing

Antegrade intramedullary nailing of femoral shaft fractures is a tried and tested treatment modality that has yielded consistently high union rates. Retrograde nailing is controversial as the approach violates the knee joint. We report two cases in which both patients had an arthrodesis of the hip and subsequently suffered a femoral shaft fracture distal to the implant. We feel that this would be an indication for retrograde nailing.

Use of titanium prosthesis to bridge a vertebral gap in the spine--a preliminary experimental study

Resection of a vertebral body for spine tumour or fracture results in a vertebral gap which has to be bridged by autogenous graft, allograft, bone cement or metal spacer. Recently, there have been several metal spacers in the market. We have designed a titanium vertebral spacer which is extensible by way of a threaded mechanism. Coating with hydroxyapatite enables bone ingrowth onto the surface of the titanium spacer. Biomechanical analysis, using the Instron biaxial electro-servohydraulic testing machine, showed that the segment bridging the spacer was rigid and stiffer than the adjacent vertebral body motion segment. Histological study showed that there was bone growth across the vertebral gap indicating fusion had taken place.