Relationship between increased knee joint line obliquity after medial open-wedge high tibial osteotomy and patient-reported outcome measures

INTRODUCTION

This study evaluated the correlation between postoperative knee joint line obliquity after medial open-wedge high tibial osteotomy and patient-reported outcome measures excluding excessively overcorrected knees. This study further identified preoperative radiological factors related to the increased postoperative knee joint line obliquity.

MATERIALS AND METHODS

We retrospectively evaluated patients who underwent medial open-wedge high tibial osteotomy between March 2013 and March 2021. Postoperative excessively overcorrected knees with hip-knee-ankle angle > 7° were excluded. We investigated radiological parameters and patient-reported outcome measures preoperatively and at the last follow-up. The following radiologic parameters were measured: hip-knee-ankle angle, weight-bearing line ratio, mechanical medial proximal tibial angle, mechanical lateral distal femoral angle, lateral distal tibial angle, joint line convergent angle, knee joint line obliquity, ankle joint line obliquity, hip abduction angle, tibial posterior slope, Carton-Deschamps index, and patella tilting angle. Clinical outcomes were evaluated using Japanese knee outcome measures. This assessment criterion is based on the Western Ontario McMaster Universities Arthritis Index and MOS Short Form 36. Multiple regression analysis was performed to evaluate the association between postoperative knee joint line obliquity and patient-reported outcome measures or preoperative radiological factors (P < .05).

RESULTS

A total of 52 knees were included. The mean age at the time of the surgery was 61.6 ± 9.0 years and the mean follow-up period was 30.6 ± 10.1 months. Increased postoperative knee joint line obliquity was associated with lower Japanese knee outcome measures. The preoperative hip-knee-ankle angle was significantly associated with postoperative knee joint line obliquity.

CONCLUSIONS

Increased knee joint line obliquity after medial open-wedge high tibial osteotomy is associated with inferior clinical outcomes. Care should be given to the center of the rotational angulation in around-knee osteotomy to avoid postoperative increased knee joint line obliquity.

LEVEL OF EVIDENCE

Retrospective comparative study, Level III.

Comparison of different degrees of varus deformity correction with open-wedge high tibial osteotomy: a retrospective study over 5 years

OBJECTIVE

This study aims to investigate the clinical efficacy and complications associated with open-wedge high tibial osteotomy (OWHTO) in the treatment of medial compartment knee osteoarthritis. Additionally, the compensatory changes in the hip, patellofemoral, and ankle regions will be assessed through imaging.

METHODS

A retrospective analysis of clinical data pertaining to 86 patients who underwent OWHTO at the Affiliated Hospital of Qingdao University from January 2015 to September 2018 was conducted. The weight-bearing line ratio (WBLR) was measured postoperatively, and patients were categorized into a normal group (50% < WBLR ≤ 62.5%, n = 67) and an overcorrection group (WBLR > 62.5%, n = 19). Various parameters, including hip-knee-ankle angle (HKA), medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), joint line convergence angle (JLCA), and posterior tibial slope (PTS), were measured before surgery and at the last follow-up to assess lower limb line correction. The compensatory changes in adjacent joints were evaluated by measuring hip abductor angle (HAA), tibial plafond inclination (TPI), talus inclination angle (TIA), Carton-Deschamps index, lateral patellar tilt (LPT), lateral patellar shift (LPS), medial patellofemoral space, and lateral patellofemoral space in both groups. The American Hospital for Special Surgery (HSS) score and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) of the affected knee were assessed before surgery and at the last follow-up, and the incidence of complications in both groups was analyzed.

RESULTS

Postoperative complications occurred in 26.32% (five cases) of the overcorrection group and 5.97% (four cases) of the normal group, with a statistically significant difference (χ2 = 4.548, p = 0.033). No significant differences were observed in HSS and WOMAC between the two groups at the last follow-up. HAA was - 2.44 ± 1.98° in the overcorrection group and - 1.16 ± 2.1° in the normal group, with a statistically significant difference (t = 2.32, p = 0.023). There were no significant differences in other imaging indexes.

CONCLUSION

Overcorrection of varus deformity may not significantly impact clinical outcomes within 5 years post-OWHTO but may elevate the incidence of postoperative complications and lead to increased compensatory adduction of the hip.

Anterior fusion surgery with overcorrection in the treatment of adolescent idiopathic scoliosis with Lenke 1 AR curve type: how to achieve overcorrection and its effect on postoperative spinal alignment

BACKGROUND

The efficacy of anterior fusion with overcorrection in the instrumented vertebra for Lenke 1 AR type curves has been reported, but how to achieve overcorrection and how overcorrection affects spinal alignment are unclear. The purpose of this study was to identify the factors that cause overcorrection, and to investigate how overcorrection affects postoperative spinal alignment in the surgical treatment of Lenke 1 AR type curves.

METHODS

Patients who had anterior surgery for a Lenke type 1 or 2 and lumbar modifier AR (L4 vertebral tilt to the right) type scoliosis and minimum 2-year follow-up were included. The radiographic data were measured at preoperative, postoperative 1 month, and final follow-up. The UIV-LIV Cobb angle was determined as the Cobb angle between the upper instrumented vertebra (UIV) and the lower instrumented vertebra (LIV), and a negative number for this angle was considered overcorrection. The screw angle was determined to be the sum of the angle formed by the screw axis and the lower and upper endplates in the LIV and UIV, respectively. The change (Δ) in the parameters from postoperative to final follow-up was calculated. The relationships between the UIV-LIV Cobb angle and other radiographic parameters were evaluated by linear regression analyses.

RESULTS

Fourteen patients met the inclusion criteria. Their median age was 15.5 years, and the median follow-up period was 53.6 months. The median UIV-LIV Cobb angle was -1.4° at postoperative 1 month. The median screw angle was 4.7°, and overcorrection was achieved in 11 (79%) cases at postoperative 1 month. The screw angle (r2 = 0.42, p = 0.012) and Δ FDUV-CSVL (the deviation of the first distal uninstrumented vertebra from the central sacral vertical line, r2 = 0.53, p = 0.003) were significantly correlated with the UIV-LIV Cobb angle.

CONCLUSIONS

Screw placement in the UIV and LIV not parallel to the endplate, but angled, was an effective method to facilitate overcorrection in the instrumented vertebrae. The results of the present study suggest that overcorrection could bring spontaneous improvement of coronal balance below the instrumented segment during the postoperative period.

Vertebral body tethering in adolescent idiopathic scoliosis with more than 2 years of follow-up- systematic review and meta-analysis

BACKGROUND CONTEXT

Whilst spinal fusion remains the gold standard in the treatment of adolescent idiopathic scoliosis (AIS), anterior vertebral body tethering (AVBT) is gaining momentum with relatively few studies on its efficacy thus far.

PURPOSE

To conduct a systematic review reporting on the early results of AVBT for patients undergoing surgery for AIS. We aimed to systematically evaluate the relevant literature pertaining to the efficacy of AVBT with respect to degree of correction of the major curve Cobb angle, complications and revision rates.

STUDY DESIGN/SETTING

Systematic review.

PATIENT SAMPLE

Of a total of 259 articles, 9 studies met the inclusion criteria and were analysed. Overall, 196 patients of (mean age 12.08 years) underwent an AVBT procedure for correction of AIS with a mean follow-up of 34 months.

OUTCOME MEASURES

Degree of Cobb angle correction, complications and revision rates were used as outcome measures.

METHODS

A systematic review of the literature on AVBT was performed for studies published between Jan 1999-March 2021 applying the PRISMA guidelines. Isolated case reports were excluded.

RESULTS

Overall, 196 patients of (mean age 12.08 years) underwent an AVBT procedure for correction of AIS with a mean follow-up of 34 months. There was a significant correction of the main thoracic curve of scoliosis (mean preoperative Cobb angle 48.5°, post-operative Cobb angle at final follow-up of 20.1°, P = 0.01). Overcorrection and mechanical complications were seen in 14.3% and 27.5% of cases, respectively. Pulmonary complications including atelectasis and pleural effusion were seen in 9.7% of patients. Tether revision was performed in 7.85%, and revision to a spinal fusion in 7.88%.

CONCLUSION

This systematic review incorporated 9 studies of AVBT and 196 patients with AIS. The complication and revision to spinal fusion rates were 27.5% and 7.88%, respectively. The current literature on AVBT is restricted largely to retrospective studies with non-randomised data. We would recommend a prospective, multi-centre trial of AVBT with strict inclusion criteria and standardised outcome measures.

Introduction of a New Radiographic Parameter to Predict Proximal Junctional Kyphosis in Adult Spinal Deformity: UIVPTA (Uppermost Instrumented Vertebra-Pelvic Tilt Angle)

OBJECTIVE

To introduce a new sagittal parameter, uppermost instrumented vertebra-pelvic tilt angle (UIVPTA), and to determine the effects on the proximal junctional kyphosis (PJK) development in adult spinal deformity (ASD) surgery.

METHODS

Patients ≥ 60 years with ASD who underwent low thoracic spine to pelvis fusion with a minimum of 2-years of follow-up were included in this study. Two groups were created according to PJK development. Various clinical and radiographic factors were compared between PJK and non-PJK groups to identify the risk factors for PJK. Cutoff value of UIVPTA for PJK development was calculated using receiver operating characteristic curve according to different pelvic incidence groups. Linear regression analysis was performed to identify factors to affect UIVPTA.

RESULTS

One hundred fifity-one patients were included in this study. There were 135 female patients (89.4%). Mean age was 70.5 years. PJK developed in 65 patients (43.0%). Multivariate analysis showed that overcorrection relative to age-adjusted pelvic incidence (PI) minus lumbar lordosis (LL) (PI-LL) target and lower UIVPTA were independent risk factors for PJK. The cutoff value of UIVPTA for PJK development was calculated as 4.0° in patients with PI less than 45°, 9.5° in patients with PI between 45° and 60°, and 13.0° in patients with PI greater than 60°. Linear regression analysis showed that UIVPTA was positively affected by postoperative values of LL (coefficient = 0.505), PI-LL (coefficient = 0.674), and pelvic tilt (coefficient = 0.286).

CONCLUSION

Optimal correction within the age-adjusted PI-LL combined with keeping UIVPTA within optimal range is suggested for the prevention of PJK.

Natural behaviours after guided growth for idiopathic genu valgum correction: comparison between percutaneous transphyseal screw and tension-band plate

BACKGROUND

Percutaneous epiphysiodesis using a transphyseal screw (PETS) or tension-band plating (TBP) has shown favourable correction results; however, the physeal behaviours in terms of rebound, stable correction, or overcorrection after guided growth have not been completely understood. In patients with idiopathic genu valgum, we therefore asked: (1) How is the correction maintained after implant removal of guided growth? (2) Is there any difference in the natural behaviours after PETS or TBP removal at the femur and tibia?

METHODS

We retrospectively reviewed 73 skeletally immature limbs with idiopathic genu valgum treated with PETS or TBP. PETS was performed in 23 distal femurs and 13 proximal tibias, and TBP was performed in 27 distal femurs and ten proximal tibias. Mechanical axis deviation (MAD), mechanical lateral distal femoral angle (mLDFA), and mechanical medial proximal tibial angle were measured at pre-correction, implant removal, and final follow-up. Changes of ≤ 3° in mechanical angles after implant removal were considered stable. Comparisons between the implant, anatomical site, and existence of rebound were performed.

RESULTS

The mean MAD improved from - 18.8 mm to 11.3 mm at implant removal and decreased to -0.2 mm at the final follow-up. At the final follow-up, 39 limbs (53.4%) remained stable and only 12 (16.4%) were overcorrected. However, 22 limbs (30.1%) showed rebound. TBP was more common, and the correction period was longer in the rebound group (p < 0.001 and 0.013, respectively). In femurs treated with PETS, the mean mLDFA increased from 86.9° at implant removal to 88.4° at the final follow-up (p = 0.031), demonstrating overcorrection. However, a significant rebound from 89.7° to 87.1° was noted at the femur in the TBP group (p < 0.001). The correction of the proximal tibia did not change after implant removal.

CONCLUSION

The rebound was more common than overcorrection after guided growth; however, approximately half the cases demonstrated stable correction. The overcorrection occurred after PETS in the distal femur, while cases with TBP had a higher probability of rebound. The proximal tibia was stable after implant removal. The subsequent physeal behaviours after each implant removal should be considered in the guided growth.

Preoperative joint line convergence angle correction is a key factor in optimising accuracy in varus knee correction osteotomy

PURPOSE

This study aimed to identify and prevent preoperative factors that can be influenced in preoperative planning to reduce postoperative malcorrections.

METHODS

The method used in this study was a retrospective two-centre analysis of 78 pre and postoperative fully weight-bearing radiographs of patients who underwent valgus osteotomy correction due to symptomatic medial compartment osteoarthritis. A computer software (TraumaCad^®) was used to aim for an intersection point of the mechanical tibiofemoral axis (mTFA) with the tibia plateau at 55-60% (medial = 0%, lateral = 100%). Postoperative divergence ± 5% of this point was defined as over- and undercorrection. Preoperative joint geometry factors were correlated with postoperative malcorrection. Planning was conducted using the established method described by Miniaci (Group A) and with additional correction of the joint line convergence angle (JLCA) using the formula JLCA-2/2 (Group B). Additionally, in a small clinical case series, planning was conducted with JLCA correction. Statistical analysis was performed using (multiple) linear regression analysis and analysis of variance (ANOVA) with p < 0.05 considered significant.

RESULTS

In 78 analysed cases, postoperative malcorrection was detected in 37.2% (5.1% undercorrection, 32.1% overcorrection). Linear regression analysis revealed preoperative body mass index (BMI, p = 0.04), JLCA (p = 0.0001), and osteotomy level divergence (p = 0.0005) as factors correlated with overcorrection. In a multiple regression analysis, JLCA and osteotomy level divergence remained significant factors. Preoperative JLCA correction reduced the planned osteotomy gap (A 9.7 ± 2.8 mm vs B 8.3 ± 2.4 mm; p > 0.05) and postoperative medial proximal tibial angle (MPTA: A 94.3 ± 2.1° vs B 92.3 ± 1.5°; p < .05) in patients with preoperative JLCA ≥ 4°. The results were validated using a virtual postoperative correction of cases with overcorrection. A case series (n = 8) with a preoperative JLCA > 4 revealed a postoperative accuracy using the JLCA correction of 3.4 ± 1.9%.

CONCLUSION

Preoperative JLCA ≥ 4° and tibial osteotomy level divergence were identified as risk factors for postoperative overcorrection. Preoperative JLCA correction using the formula JLCA-2/2 is proposed to better control ideal postoperative correction and reduce MPTA. The intraoperatively realised osteotomy level should be precisely in accordance with preoperative planning.

LEVEL OF EVIDENCE

III, cross-sectional study.

How to achieve an optimal alignment in medial opening wedge high tibial osteotomy?

Medial opening wedge high tibial osteotomy (MOWHTO) is a widely used surgical treatment option for medial compartmental osteoarthritis with varus deformity. It is important that proper lower limb alignment is achieved. However, there has been no consensus about an optimal alignment in MOWHTO. Most studies suggest that achieving valgus alignment is necessary, and recent studies support slight valgus mechanical alignment of less than 3° of mechanical femorotibial angle. Overcorrection and undercorrection is not recommended for achieving good surgical outcomes. To prevent undercorrection and overcorrection in MOWHTO, the method of placing the weight-bearing line in the target range must be precise. There are several ways to place a weight-bearing line within the target range. While the most important factor for a successful MOWHTO is achieving an ideal mechanical axis correction, there are a few other factors to consider, including joint line obliquity, posterior tibial slope, ligament balancing, and patellar height. Several factors exist that lead to undercorrection and overcorrection. Preoperative amount of varus deformity, lateral hinge fracture, and fixation failure can result in undercorrection, while medial soft tissue laxity and the amount of correction angle and target point beyond hypomochlion can result in overcorrection. This study aimed to review the literature on optimal alignment in MOWHTO and report on the factors to be considered to prevent correction errors and how to achieve an optimal alignment.

The Overcorrected Clubfoot in Children

Clubfoot overcorrection can develop gradually over years and is characterized in school age by hindfoot valgus position due to excessive rigid peritalar eversion, sometimes accompanied by supramalleolar valgus malalignment. Surgical treatment is recommended in severe cases and consists of bony realignment at the peritalar complex by osteotomy or fusion, correction of the supramalleolar valgus deformity in younger children by hemiepiphyseodesis, or osteotomy in adolescents. In addition, dorsal bunion requires stabilization of the medial tarsometatarsal ray and transfer of the tendons of Mm. tibialis anterior and flexor hallucis longus.

Temporary Kirschner wire fixation of the first metatarsophalangeal joint before osteotomy for hallux valgus

INTRODUCTION

Numerous operative procedures have been described for correction of hallux valgus, including distal step-cut osteotomy such as the Mitchell osteotomy. However, overcorrection can occur due to technical problems with the initial metatarsal osteotomy. Here, we describe a modified Mitchell osteotomy with a novel method, the temporary Kirschner wire fixation of the first metatarsophalangeal joint (TeKFiM) method (Tonogai method), that can be used before osteotomy for hallux valgus to avoid incongruency and overcorrection.

OPERATIVE TECHNIQUE

A skin incision and Y-shaped capsulotomy are performed and the medial exostosis is excised. Lateral capsule release is done if the first metatarsophalangeal (MTP) joint cannot be reduced manually. Next, a Kirschner wire (K-wire) is inserted subcutaneously through the medial side of the first proximal phalanx to the lateral side of the first metatarsal to preserve the correct congruency of the first MTP joint during surgery. To correct pronation of the distal fragment, step-off transverse cuts are made in the distal fragment, as described by Mitchell, reaching one-second to two-thirds of the transverse diameter of the neck from the plantar medial side. After the osteotomies are completed, the lateral spike of the proximal fragment is flattened. The distal fragment is displaced laterally and slightly plantarward, and the pronation deformity of the distal fragment is corrected by inserting a K-wire to act as a joystick. The osteotomy site is stabilized using two Herbert-type screws. After removal of the K-wire, the operation is completed by closing the medial capsule of the first MTP joint and the skin. A plantar cast is applied for 2 weeks, followed by a special heel brace for 4-6 weeks. Sutures are removed 2 weeks after surgery. Patients are allowed to start weightbearing gradually as tolerated from 2 weeks after surgery.

DISCUSSION

After osteotomy, it is difficult to maintain the correct congruency of the first MTP joint due to instability of the distal fragment. The TeKFiM method (Tonogai method) reliably maintains this congruency during surgery. Also, by using a K-wire as a joystick to fix the joint in correct congruency, the first toe is rotated and pronation is corrected by supinating the distal fragment. The K-wire also serves as a landmark for determining how far the distal fragment is shifted plantarward.

CONCLUSIONS

We have developed a modified Mitchell osteotomy with the novel TeKFiM method (Tonogai method) before osteotomy for hallux valgus to avoid incongruency and overcorrection. This method also provides a landmark to correct pronation and plantarward shifting.

Evaluation of Desmopressin in Critically Ill Patients with Hyponatremia Requiring 3% Hypertonic Saline

BACKGROUND

Desmopressin (DDAVP) is often used for hyponatremia management but has been associated with increases in hospital length of stay and duration of hypertonic saline use. The purpose of this study was to evaluate hyponatremia management strategies and their effect on sodium correction in critically ill patients requiring 3% hypertonic saline (3HS).

METHODS

This retrospective, single-center study included critically ill patients with hyponatremia (serum sodium ≤ 125 mEq/L) receiving 3HS from May 31 2015, to May 31 2019. Patients were divided into those who received 3HS for hyponatremia management (HTS) and those who received proactive or reactive DDAVP in addition to 3HS (D-HTS). Patients in either group could receive rescue DDAVP. The primary outcome was the percentage of patients achieving goal sodium correction of 5-10 mEq/L 24 h after 3HS initiation.

RESULTS

Goal sodium correction was achieved in 52.5% of patients in HTS compared to 65.6% of patients in D-HTS (p = 0.21). Patients in HTS had a shorter duration of 3HS infusion (p = 0.0022) with no difference in ICU length of stay, free water intake, urine output, or serum sodium increases 12 and 24 h after receiving 3HS. Overcorrection during any 24- or 48 h period was not statistically different between groups.

CONCLUSION

Patients in HTS and D-HTS had similar rates of achieving goal sodium correction at 24 h. A proactive or reactive DDAVP strategy led to an increase in 3HS duration and total amount with no significant difference in rates of overcorrection. Prospective, randomized studies assessing standardized strategies for hyponatremia management and DDAVP administration are warranted.

Association of intranasal desmopressin therapy with overcorrection of severe hyponatremia: A retrospective, propensity score-based, single-center cohort study

PURPOSE

Severe hyponatremia, defined as serum sodium concentration ([sNa]) ≤ 120 mEq/L, requires aggressive treatment to prevent potentially fatal cerebral edema, seizures, and other sequelae, but overcorrection can also result in life-threatening cerebral hemorrhage and demyelination. We compared the safety and efficacy of nasal desmopressin to conventional management for the prevention of [sNa] overcorrection.

MATERIAL AND METHODS

This retrospective analysis compared 47 patients treated with desmopressin to 17 patients treated conventionally at a university hospital ICU in Japan between 2013 and 2018 using propensity score-based approaches. The primary outcome was safe [sNa] correction, defined as a ≤ 8 mEq/L difference between baseline and follow-up [sNa] at any time within 24h of diagnosis.

RESULTS

The 24-h safe correction rate was significantly greater in the desmopressin group than the conventional treatment group (68% [32/47] vs. 41% [7/17], P = 0.039), and dose-response analysis indicated a positive association between cumulative 24-h desmopressin dose and safe correction at 24 h (P = 0.003). Few overcorrections precluded reliable assessment at 48 h. Exacerbation of hyponatremia was comparable in the two treatment groups.

CONCLUSIONS

Intranasal desmopressin therapy increased the safe correction of severe hyponatremia. Large prospective trials are warranted to confirm this result.

Overcorrection of fractured vertebrae increases the incidence of adjacent fractures after balloon kyphoplasty: A retrospective study

Purpose

To investigate whether the correction amount by balloon kyphoplasty (BKP) is associated with the incidence of adjacent vertebral fractures (AVF).

Methods

Data from 61 patients without and 25 patients with AVF were analyzed. A linear regression model was used between vertebral instability and corrected angle or height to divide patients into the overcorrection and undercorrection groups.

Results

Vertebral fractures overcorrected for instability led to a higher incidence rate of AVF [42.4% and 46.9% with overcorrection vs. 10.7% and 13.3% with undercorrection for angle and height, respectively].

Conclusions

Overcorrection of fractured vertebrae may associate with the increased incidence of AVF.

Scoliosis in Goldenhar syndrome with curve reversal during brace treatment: a case report

Background

Goldenhar syndrome sometimes displays progressive scoliosis and other spinal deformities that require treatment. However, few reports exist on scoliosis correction in Goldenhar syndrome. We described the rare radiological outcomes of a patient with Goldenhar syndrome who received brace treatment for scoliosis.

Case presentation

A 4-year-old boy was diagnosed as having Goldenhar syndrome and referred to our hospital for scoliosis treatment. The deformity deteriorated gradually, and left convex scoliotic angle was 26 degrees (T3-L2) at 11 years of age. Unexpectedly during treatment with an orthopedic brace, the curve had reversed to 21 degrees (T5-L2) at 7 months of therapy. After another adjustment of the brace, his right convex scoliotic angle improved to 13 degrees (T4-L2) at 15 months of treatment.

Conclusions

Curve reversal may occur during brace treatment for scoliosis in Goldenhar syndrome. Clinicians may opt to periodically check curve correction despite the risk of increased radiation exposure.

Increased preoperative medial and lateral laxity is a predictor of overcorrection in open wedge high tibial osteotomy

PURPOSE

This study aimed at determining whether overcorrection after open wedge high tibial osteotomy (OWHTO) would be predicted by the magnitude of preoperative medial and lateral coronal soft tissue laxity around the knee joint.

METHODS

Overall, 68 knees of 62 patients who underwent OWHTO for primary medial osteoarthritis were retrospectively reviewed. The mechanical hip-knee-ankle (HKA) axis, weight-bearing line (WBL) ratio, medial proximal tibial angle (MPTA), joint line obliquity, coronal subluxation, and joint line convergence angle (JLCA) were measured on full-weight-bearing long-standing HKA radiographs preoperatively and at 1 year postoperatively. The varus valgus stress angle was measured on preoperative radiographs. The correction amount due to soft tissue factors was calculated as the difference between the WBL ratio on postoperative 1-year radiographs and that on virtually corrected preoperative radiographs with the same amount of MPTA at 1 year postoperatively. The patients were grouped according to the presence or absence of a ≥ 10% overcorrection of WBL ratio (overcorrection or expected correction). Multiple logistic regression analysis was performed to identify the preoperative risk factors of overcorrection.

RESULTS

The average WBL ratio was corrected from 19.0 ± 13.5% preoperatively to 61.6 ± 9.1% postoperatively (P < 0.001). The average MPTA changed from 85.1 ± 1.7° preoperatively to 93.6 ± 2.6° postoperatively, resulting in an average tibia correction angle of 8.6 ± 3.1°. The average estimated correction from soft tissue factors was 5.8 ± 7.4% of the WBL ratio. Soft tissue correction of the WBL ratio > 10% was confirmed in 17 patients (28%). The preoperative JLCA and valgus stress angle were significantly greater in the overcorrection group than in the expected correction group: 5.0 ± 1.7° vs. 3.4 ± 1.9° (P = 0.003) and 2.4 ± 1.0° vs. 1.3 ± 1.2° (P = 0.002), respectively. Among the radiologic parameters, the presence of both ≥ 4° JLCA and ≥ 1.5° valgus stress angle was the only significant risk factor for overcorrection from soft tissue factors (P = 0.006; odds ratio, 30.2).

CONCLUSIONS

The magnitude of both medial and lateral coronal soft tissue laxity was a predictor of overcorrection from soft tissue factors after OWHTO. Overcorrection was more likely to occur in cases with both ≥ 4° JLCA and ≥ 1.5° valgus stress angle.

LEVEL OF EVIDENCE

III.

Long term clinical results of hallux varus correction by a reversed abductor hallucis transfer

BACKGROUND

Iatrogenic hallux varus is a rare complication after hallux valgus surgery. Operative treatment comprises a wide variety of techniques, of which the reversed transfer of the abductor hallucis tendon is the most recent described technique.

METHODS

This paper will present the long-term clinical results of the reversed transfer of the abductor hallucis longus. Therefore, we performed a prospective clinical observational study on 16 female patients. Our hypothesis is that the tendon transfer will persist in a good alignment and patient satisfaction on long term. There is a 100% follow-up rate with a range from 10 to 101 months. Patients were subjected to a clinical examination, three questionnaires and their general satisfaction.

RESULTS

Out of 16 patients, at time of follow-up, we found a positive correlation between the subjective outcome score and alignment (r=0.59), and between the general satisfaction and alignment (r=0.77). Based on the general satisfaction we achieved a success satisfaction rate of 69% (11 patients). The other 31% (5 patients) patient group was only satisfied with major reservations or not satisfied at all. The two most invalidating complications were a coronal or sagittal malalignment or the combination of both.

CONCLUSIONS

Our results suggest that the reverse abductor hallucis tendon transfer is a good technique to treat a supple iatrogenic hallux varus with an observed success satisfaction rate of 69% at a mean follow-up time of 48 (range 10-101) months. However, patients should be informed that on the long-term loss of correction is possible.

LEVEL OF EVIDENCE

Prospective clinical observational study: Level IIb.

Managing intra-articular deformity in high Tibial osteotomy: a narrative review

The joint line convergence angle (JLCA) has a normal range between 0° to 2°, which increases in magnitude depending on the severity and stage of osteoarthritis in the knee.

The JLCA represents the interaction of the intra-articular deformity arising from the osteoarthritis and the surrounding soft tissue laxity. Therefore, the JLCA has become a vital parameter in analysing the long leg alignment views for corrective planning before osteotomy surgery. Recent studies have considered the influence on how the preoperative JLCA is measured and its influence on achieving accurate postoperative desired correction in high tibial osteotomy surgery.

The JLCA also reflects the influence of soft tissue laxity in a lower limb malalignment and many surgeons encourage it to be taken into account to avoid non physiological correction and/or overcorrection with negatively impacted postoperative patient outcome.

This present review addressed how to obtain an accurate preoperative measurement of the JLCA, its influence on postoperative deformity analysis and how to reduce errors arising from an elevated preoperative JLCA.

We have proposed a formula to help determine the value to subtract from the planned correction in order to avoid an overcorrection when performing a corrective osteotomy.

Level of clinical evidence IV, narrative review.

Difference in joint line convergence angle between the supine and standing positions is the most important predictive factor of coronal correction error after medial opening wedge high tibial osteotomy

PURPOSE

Coronal correction errors after medial opening wedge high tibial osteotomy (MOWHTO) occasionally occur even with the assistance of navigation. The purpose of the present study was to determine the navigation accuracy in MOWHTO and to identify factors that affect the coronal correction error after navigation-assisted MOWHTO.

METHODS

A total of 114 knees treated with navigation-assisted MOWHTO were reviewed retrospectively. Mechanical axis (MA) on standing radiograph and medial proximal tibial angle (MPTA) were measured preoperatively and at 6 months postoperatively, and the differences (ΔMA and ΔMPTA) were calculated. Joint line convergence angle (JLCA) on supine and standing radiographs was measured preoperatively, and their difference (ΔJLCA) was calculated. To assess the navigation accuracy, ΔMA and ΔMPTA were compared with the coronal correction by navigation (ΔNMA) using intraclass correlation coefficients (ICCs). Univariable and multivariable regression analyses were used to identify factors that affect coronal correction discrepancy (ΔMA - ΔNMA).

RESULTS

The reliability of navigation was good in terms of bony correction (ICC between ΔNMA and ΔMPTA, 0.844) and fair in terms of MA correction (ICC between ΔNMA and ΔMA, 0.706). The mean coronal correction discrepancy was 2.0° ± 2.4°. In the multivariable analysis, ΔJLCA was shown to be a predictive factor of coronal correction discrepancy (unstandardized coefficient, 1.026; R², 0.470).

CONCLUSION

Navigation in MOWHTO provided reliable information about bony correction; however, MA tended to be overcorrected. The difference in JLCA between the supine and standing radiographs was the most important preoperative factor that predicted the coronal correction discrepancy after MOWHTO. In patients with larger ΔJLCA, each degree of ΔJLCA should be subtracted from the planned amount of correction angle when preoperative planning is performed using standing radiographs.

LEVEL OF EVIDENCE

IV.

Preoperative latent medial laxity and correction angle are crucial factors for overcorrection in medial open-wedge high tibial osteotomy

PURPOSE

This study aimed to determine which preoperative factors affect the postoperative change in the joint line convergence angle (JLCA) by preoperatively quantifying soft tissue laxity.

METHODS

Thirty-four patients who underwent medial open-wedge high tibial osteotomy (HTO) with a navigation were analysed. The JLCA change after HTO was calculated using standing long-bone anteroposterior radiographs taken preoperatively and 6 months postoperatively. Latent soft tissue laxity was defined as the amount of soft tissue that can be extended to valgus or varus from the weight-bearing position, and calculated by subtracting the JLCA on weight-bearing standing radiographs from that on stress radiographs. Multiple linear regression was performed to determine the preoperative factors that statistically correlated with the postoperative JLCA change.

RESULTS

In multiple linear regression, JLCA change had a statistically significant correlation with latent medial laxity (R = 0.6) and a statistically borderline significant correlation with correction angle (R = 0.2). These imply that the postoperative JLCA change increased by 0.6° per 1° increase in latent medial laxity, and increased by 0.2° per 1° increase in correction angle. Latent medial laxity was the most crucial factor associated with postoperative JLCA changes.

CONCLUSION

The JLCA change could be larger in patients with large latent medial laxity or severe varus deformity requiring a large correction, which could lead to unexpected overcorrection in HTO. Postoperative JLCA change should be considered in preoperative surgical planning. Target point shifting within the hypomochlion point could be a strategy to prevent overcorrection, especially in patients with large latent medial laxity.

LEVEL OF EVIDENCE

Level IV.

Does overcorrection cause any negative effect on pediatric missed Monteggia lesion?

PURPOSES

To evaluate the outcome of different types of ulna osteotomy in missed Monteggia fracture with a particular interest in anatomical correction and overcorrection techniques. The outcome between the two groups were compared on aspects of (1) clinical outcome (2) radiologic outcome.

METHODS

Twenty-one patients with type 1 missed Monteggia fracture who underwent surgery between January 2005-2018 were retrospectively reviewed. The patients were divided into two groups according to the degrees of correction: group 1 anatomical correction (no ulnar dorsal angulation) and group 2 overcorrection (degrees of ulnar dorsal angulation ≥ 10°). Clinical outcomes were assessed using the Kim elbow performance score. Radiologic outcomes were categorized into four groups with regard to the radial head: excellent (complete reduction), good (slight subluxation), fair (moderate subluxation), and poor (dislocation).

RESULTS

Eleven patients with anatomical ulna osteotomy and ten patients with overcorrection ulnar osteotomy were enrolled with a mean age of 7.95 (5-12) years at the time of operation. The mean duration from injury to surgery was 27.05 (3-120) months, and the mean period of follow-up was 29.90 ± 22.37 (12-84) months. The average angle of total correction measured in group 1 was 6.09° (3°-9°) and 28.37° (12°-40°), in group 2. Fair-to-poor radiological outcomes at the last follow-up were more frequently observed in overcorrection group (40% vs. 0%) (p = 0.035) as well as clinical outcome (20% vs. 0%) (p = 0.214). Among the patients in group 2, posterior dislocation was diagnosed in two patients at 18 months and 2 months after surgery.

CONCLUSION

The postoperative result of overcorrection ulna osteotomy showed significant inferiority in radiologic outcome compared to anatomical correction. Overcorrection of ulna osteotomy could be associated with posterior dislocation of radial head.

Does an overcorrected clubfoot caused by surgery or by the Ponseti method behave differently?

BACKGROUND

Overcorrection is a recognized problem following surgical treatment of congenital clubfoot. Recently this complication has also been mentioned following Ponseti treatment.

RESEARCH QUESTION

Do overcorrected clubfeet (OCCF) caused by surgery behave differently from those caused by Ponseti treatment in terms of segmental motion of the feet and show differences in the severity of deformity on X-rays?

METHODS

Children between 7 and 12 years with OCCF were included in this study. Depending on the aetiology causing them, the feet were divided into 2 groups (Ponseti and peritalar release surgery). 25 typically developing children served as controls. All subjects were subjected to clinical and radiological examination and 3-Dimensional gait analysis using the Oxford Foot Model.

RESULTS

Thirty-two children with OCCF, of these 18 feet in the surgical and 14 feet in the Ponseti group, were included in the study. No radiological differences were seen in the flatfoot parameters between OCCF groups except in the calcaneal inclination angle that was more pathological in the Ponseti group. The clinical ankle plantar flexion was significantly reduced in the surgical group. During walking the range motion of the hindfoot in the frontal plane was significantly reduced in surgically treated feet compared to the Ponseti group. The other parameters did not show any significant difference between groups.

SIGNIFICANCE

The overcorrected clubfeet following surgery and Ponseti showed similar appearance and showed no significant differences in 11/12 radiological parameters. The segmental motion of the feet showed no significant differences between groups except the in the range of motion of the subtalar eversion. A considerable subtalar joint motion was present even in the surgical group. These findings might help plan the treatment of these feet.

Risk factors for sodium overcorrection in non-hypovolemic hyponatremia patients treated with tolvaptan

PURPOSE

In this study, the risk factors associated with sodium overcorrection were investigated with an optimal cutoff for baseline serum sodium for use in daily clinical practice.

METHODS

Electronic medical records of patients who received tolvaptan for non-hypovolemic hyponatremia were reviewed. Demographic and clinical data including age, sex, weight, height, comorbidity, cause of hyponatremia, hypertonic saline use, and comedication were collected. Baseline laboratory parameters measured included serum sodium, serum potassium, serum creatinine, blood urea nitrogen, serum tonicity, ALT, AST, and urine osmolality. The primary outcome was the overcorrection of serum sodium, which was defined as an increase in serum sodium by more than 10 mmol/L in 24 h.

RESULTS

From a total of 77 patients included in the analysis, 24 (31.2%) showed sodium overcorrection (> 10 mmol/L/24 h); 2 (2.6%) in heart failure cohort, 17 (22.1%) in SIADH cohort, and 5 (6.5%) in unknown cause cohort. More than half of patients (51.9%) were administered hypertonic saline prior to tolvaptan. Hypertension, cancer, diuretics, baseline serum sodium, and SIADH were associated with the risk of overcorrection in the univariable analysis. Significant factors for the overcorrection from multivariable analysis were lower body mass index, presence of cancer (adjusted odds ratio, 10.87; 95% CI, 1.23-96.44), and lower serum sodium at baseline (adjusted odds ratio, 0.76 for every 1 mEq/L increase; 95% CI, 0.61-0.94).

CONCLUSION

The overcorrection of hyponatremia in non-hypovolemic patients treated with tolvaptan was significantly associated with lower body mass index, presence of cancer, and lower serum sodium at baseline. In subgroup analysis using SIADH patients, baseline sodium and cancer were found to be significant factors of overcorrection.

Characteristics of Patients Who Are Not Responsive to Alternate Patching for Overcorrected Intermittent Exotropia

Purpose

To compare the characteristics of patients with surgically overcorrected intermittent exotropia treated with alternate patching.

Methods

The medical records of 51 patients who underwent bilateral lateral rectus muscle recession for intermittent exotropia and required alternate patching to correct postoperative overcorrection were retrospectively reviewed. Patients with postoperative esodeviation ≥18 prism diopters (PD) were started on alternate patching on postoperative day 1, whereas those with postoperative esodeviation of 10 to 17 PD were started after 2 weeks. Postoperative esodeviation <10 PD was considered as slight intentional overcorrection after exotropia surgery. Patients not responsive to alternate patching treatment were defined as those with postoperative esodeviation ≥10 PD after 3 months of treatment. Sex, family history, age, refractive error, amblyopia, stereopsis, suppression, type of exotropia, surgical method, preoperative and postoperative angle of deviation, and start time of alternate patching were compared.

Results

Among 51 patients, 29 patients responded to alternate patching and 22 patients did not respond. Female sex (p = 0.04), larger preoperative exodeviation at distance (p = 0.04), late onset of postoperative maximal esodeviation (p < 0.01), larger postoperative maximal esodeviation at near (p = 0.02), and late initiation of alternate patching (p = 0.01) were associated with patients in the non-responsive group. Although postoperative angle of deviation was similar for 2 weeks, the angle of postoperative esodeviation was significantly larger in the non-responsive group than in the responsive group, beginning at 1 month postoperatively.

Conclusions

Female sex, large preoperative exodeviation, late initiation of alternate patching, and large esodeviation 1-month postoperative predisposed patients to be resistant to alternate patching for postoperative overcorrection.

Long-term Surgical Outcomes of Initial Postoperative Overcorrection in Adults with Intermittent Exotropia

Purpose

To evaluate the relationship between initial postoperative overcorrection and long-term surgical success in exotropia patients.

Methods

The medical records of 46 patients who underwent surgery for intermittent exotropia after the age of 18 were enrolled. Enrolled patients also had at least 2 years of postoperative follow-up. Based on the initial postoperative deviation at distance measured by prism and the alternating cover test at 1 week, patients were assigned to one of the following groups: group A included patients who demonstrated any esodeviation, while group B included patients who showed orthophoria to exodeviation of 10 prism diopters. The records were analyzed to determine the preoperative deviation with stereoacuity and postoperative deviations with stereoacuity at the follow-up examinations at the following intervals: 1 week; 1, 3, and 6 months; and 1 and 2 years. A comparison between groups for demographic data and preoperative and postoperative angles of deviation was performed using analysis of variance.

Results

Of the 46 patients with intermittent exotropia included in this study, 18 (39%) belonged to group A, while 28 (73%) belonged to group B. The postoperative angle of deviation for distant fixation until 2 years of follow-up showed statistically significant differences in each group (p < 0.003 in all comparisons). The amount of exodrift until 2 years in group A (from −9.7 ± 6.1 to 1.6 ± 3.7) was greater than that in group B (from 2.0 ± 2.7 to 6.8 ± 5.6). The long-term surgical success rate within 2 years of surgery was significantly better in group A than in group B (p = 0.027). The number of patients with intermittent diplopia and the duration of diplopia were greater in group A (n = 8) than in group B (n = 2).

Conclusions

Long-term surgical success was achieved in 89% of patients who were initially overcorrected. Overcorrection of an average of 10 prism diopters at the first postoperative week was found to be associated with a more favorable long-term surgical outcome.

Long-term development of overcorrection after femoral derotation osteotomy in children with cerebral palsy

BACKGROUND

Recent studies showed rates of recurrence of internal rotation gait (IRG) after femoral derotation osteotomy (FDO) up to 40%. Some surgeons even advice overcorrection during FDO to avoid a later recurrence.

RESEARCH QUESTION

Evaluation of the long-term development of limbs with initial overcorrection after FDO.

METHODS

29 limbs of 20 children (9.9 ± 3.2 years at surgery) with IRG, cerebral palsy (CP) and more than 5° external hip rotation postoperatively were included retrospectively. A gait analysis and clinical examination were performed preoperatively (less than one year, E0), postoperatively (9-23 months, E1) and at the long-term follow-up (at least five years postoperatively, E2). Differences between those children that remained overcorrected at E2 and those with a hip rotation within normal range at E2 were evaluated.

RESULTS

At E2 41% of these limbs remained overcorrected, 52% showed a hip rotation within normal range and 7% showed recurrence of IRG. A comparison of those limbs that remained overcorrected and those ending within normal range revealed neither a difference in age at surgery nor in static and dynamic torsional parameters at E0 and E1 except for pelvic rotation. A significantly larger pelvic internal rotation at E1 for those with remaining overcorrection could be identified.

SIGNIFICANCE

A general overcorrection during FDO in children with CP to avoid recurrence of IRG cannot be recommended, as 41% remain overcorrected. Preoperative predictors for long-term development couldn't be identified. If pelvic mal-rotation is corrected, hip rotation may change into normal range over the time in combination with the development of a flexed knee gait.

Rapidity of Correction of Hyponatremia Due to Syndrome of Inappropriate Secretion of Antidiuretic Hormone Following Tolvaptan

BACKGROUND

Tolvaptan effectively corrects hyponatremia due to the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), but undesired overcorrection can occur. We hypothesized that pretherapy parameters can predict the rapidity of response to tolvaptan in SIADH.

STUDY DESIGN

Multicenter historical cohort study.

SETTING & PARTICIPANTS

Adults with SIADH or congestive heart failure (CHF) treated with tolvaptan for a serum sodium concentration ≤ 130 mEq/L at 5 US hospitals.

PREDICTORS

Demographic and laboratory parameters.

OUTCOMES

Rate of change in serum sodium concentration.

MEASUREMENTS

Spearman correlations, analysis of variance, and multivariable linear mixed-effects models.

RESULTS

28 patients with SIADH and 39 patients with CHF treated with tolvaptan (mean baseline serum sodium, 120.6 and 122.4 mEq/L, respectively) were studied. Correction of serum sodium concentration > 12 mEq/L/d occurred in 25% of patients with SIADH compared to 3% of those with CHF (P<0.001). Among patients with SIADH, the increase in serum sodium over 24 hours was correlated with baseline serum sodium concentration (r=-0.78; P<0.001), serum urea nitrogen concentration (SUN; r=-0.76; P<0.001), and estimated glomerular filtration rate (r=0.58; P=0.01). Baseline serum sodium and SUN concentrations were identified as independent predictors of change in serum sodium concentration in multivariable analyses. When patients were grouped into 4 categories according to baseline serum sodium and SUN median values, those with both low baseline serum sodium (≤121 mEq/L) and low baseline SUN concentrations (≤10mg/dL) exhibited a significantly greater rate of increase in serum sodium concentration (mean 24-hour increase of 15.4 mEq/L) than the other 3 categories (P<0.05). Among patients with CHF, only baseline SUN concentration was identified as an independent predictor of change in serum sodium concentration over time.

LIMITATIONS

Lack of uniformity in serial serum sodium concentration determinations and documentation of water intake.

CONCLUSIONS

Baseline serum sodium and SUN values are predictive of the rapidity of hyponatremia correction following tolvaptan use in SIADH. We advise caution when dosing tolvaptan in patients with both low serum sodium and SUN concentrations.

A low initial serum sodium level is associated with an increased risk of overcorrection in patients with chronic profound hyponatremia: a retrospective cohort analysis

Background

Even with abundant evidence for osmotic demyelination in patients with hyponatremia, the risk factors for overcorrection have not been fully investigated. Therefore the purpose of this study is to clarify the risks for overcorrection during the treatment of chronic profound hyponatremia.

Methods

This is a single-center retrospective observational study. We enrolled 56 adult patients with a serum sodium (SNa) concentration of ≤125 mEq/L who were treated in an intensive care unit by nephrologists using a locally developed, fixed treatment algorithm between February 2012 and April 2014. The impact of patient parameters on the incidence of overcorrection was estimated using univariable and multivariable logistic regression models. Overcorrection was defined as an increase of SNa by >10 mEq/L and >18 mEq/L during the first 24 and 48 h, respectively.

Results

The median age was 78 years, 48.2% were male, and 94.6% of the patients presented with symptoms associated with hyponatremia. The initial median SNa was 115 mEq/L (quartile, 111–119 mEq/L). A total of 11 (19.6%) patients met the criteria for overcorrection with 9 (16.0%) occurring at 24 h, 6 (10.7%) at 48 h, and 4 (7.1%) at both 24 and 48 h. However, none of these patients developed osmotic demyelination. Primary polydipsia, initial SNa, and early urine output were the significant risk factors for overcorrection on univariable analysis. Multivariable analysis revealed that the initial SNa had a statistically significant impact on the incidence of overcorrection with an adjusted odds ratio of 0.84 (95% confidence interval, 0.70–0.98; p = 0.037) for every 1 mEq/L increase. Additionaly, the increase in SNa during the first 4 h and early urine output were significantly higher in patients with overcorrection than in those without (p = 0.001 and 0.005, respectively).

Conclusions

An initial low level of SNa was associated with an increased risk of overcorrection in patients with profound hyponatremia. In this regard, the rapid increase in SNa during the first 4 h may play an important role.

Overcorrected Flatfoot Reconstruction

The overcorrected flatfoot reconstruction is a less common but often difficult sequelae of surgical treatment of the adult acquired flatfoot deformity. Understanding the patient's symptoms and how they correlate to the procedures performed during the index surgery are paramount to determining the appropriate course of treatment. Patients' symptoms may resemble those seen in the cavovarus foot condition, often secondary to overlengthening of the lateral column or excessive displacement of the calcaneal tuberosity. Osteotomies of the calcaneus, midfoot, and often the first metatarsal may be sufficient to revise the overcorrection. However, hindfoot and/or midfoot arthrodesis may be required in more severe or rigid cases.

Intraocular lens power overestimation in a patient with history of circling keratorraphy

We report a case of cataract extraction and intraocular lens (IOL) power overestimation in a patient with history of hyperopia managed with circling keratorraphy. A 65-year-old female presented to our institute complaining of decreased vision in both eyes. The patient had a history of bilateral hyperopia that was managed 20 years ago (1994) with circling keratorraphy. At presentation her uncorrected distance visual acuity (UDVA) was 20/70 and 20/60 in her right eye (OD) and left eye (OS), respectively, while her corrected distance visual acuity (CDVA) was 20/25 OD and 20/25 OS with manifest refraction of −0.50 + 1.50 × 75 OD and +0.50sph + 1.50cyl × 30 OS. Slit lamp examination revealed the presence of a circular intrastromal corneal suture (6 mm diameter) and mild (+1) nuclear sclerosis in both eyes. The patient was scheduled to undergo cataract extraction targeting plano, using a toric IOL; one month after the surgery, the manifest refraction of the operated right eye was −2.00 + 0.50 × 175, reflecting an overestimation of the intraocular lens (IOL) power for the attempted target. Cataract extraction in patients with history of circling keratorraphy for the management of hyperopia results in IOL power overestimation, consistent with that which is seen in patients with other previous hyperopic corneal refractive procedures.

The Surgical Overcorrection of Lenke Type 1 Deformities with Selective Fusion Segments: What Happens to the Coronal Balance?

PURPOSE

The aim of our study is to determine the alterations on coronal balance after overcorrection of Lenke type 1 curve, retrospectively.

METHODS

Datas of 34 patients (29 female, 5 male patients; mean age, 16.3±3.3 years; range, 13-24 years) surgically treated for scoliosis between 2004 and 2010 were reviewed, retrospectively. The adolescent idiopathic scoliosis patients with Lenke type 1 curve treated with only posterior pedicle screw and postoperative thoracic curves less than 10° by Cobb method on frontal plane were enrolled in this study. Mean follow-up period was 52.5±29.7 months.

RESULTS

The mean amount of the preoperative thoracic curves was measured as 41.2°±6.1° (range, 30°-56°). The mean amount of the early postoperative thoracic curves was measured as 6.5°±1.8° (range, 3°-9°). The mean amount of the thoracic curves was measured as 8.5°±4.6° (range, 3°-22°) during the last follow-up (p=0.01). The mean preoperative coronal balance was measured as 8.5mm(range, 1-30mm). The mean early postoperative coronal balance was measured as 3.5mm(range, 0-36 mm). The mean coronal balance was measured as 5.5mm(range, 0-38mm) during the last follow-up (p>0.05).

CONCLUSION

We suggest that Lenke type 1B and 1C should be carefully evaluated and the fusion levels should be accurately selected in order to maintain the correction of coronal balance. We suggest that selective fusion with overcorrection in Lenke type 1A are applied to curves that can be corrected lumbar curve at the preoperative bending radiograph and curves that not have coronal decompensation and >10° distal junctional kyphosis, preoperatively.

Preoperative varus laxity correlates with overcorrection in medial opening wedge high tibial osteotomy

PURPOSE

Medial opening wedge high tibial osteotomy (HTO) is a realignment of the lower limb. Despite accurate preoperative planning and careful surgical techniques, many HTOs result in alignment correction errors. These alignment correction errors may be due to soft tissue laxity around the knee such as varus or valgus laxity. The purpose of this study was to examine the relationship of varus and valgus laxity of the knee and alignment correction errors, and to have a formula to predict the subsequent degree of these correction errors.

MATERIALS AND METHODS

Fifty knees from 41 patients undergoing opening wedge HTO for knee osteoarthritis were involved. Standing full-length anteroposterior radiographs of the lower limb and the tibia, and varus and valgus stress radiographs of the knee were used to evaluate alignment and joint laxity. Parameters were global correction (the change in the hip-knee-ankle angle), bony correction (the change in the medial proximal tibial angle), and soft tissue correction (global correction - bony correction).

RESULTS

The average of global correction, bony correction, and soft tissue correction were 12.8° ± 4.3°, 9.4° ± 3.2°, and 3.4° ± 2.5°, respectively. Preoperative varus laxity was moderately correlated with soft tissue correction (R = 0.58), and in which the slope of the line in the scatter plot represented 0.59, implying that soft tissue correction increases by 0.59° for every 1° of preoperative varus laxity.

CONCLUSIONS

Preoperative varus laxity is correlated with soft tissue correction, suggesting that more accurate alignment correction could be achieved by surgical planning taking into account preoperative varus laxity as a factor of soft tissue correction.

Evaluation and Surgical Management of the Overcorrected Clubfoot Deformity in the Adult Patient

Adult patients presenting with an overcorrected clubfoot often have had a posteromedial release. They present later in life and have compensated quite well despite the development of deformity. Minor trauma may lead to the onset of acute symptoms. A spectrum of deformity exists. Key features include a dorsally subluxated navicular, a dorsal bunion from overpull of the tibialis anterior tendon, valgus of the ankle or hindfoot or both, and a flattop talus. This article details the diagnostic approach to the overcorrected clubfoot patient and options for management of the various components of the deformity.

Postoperative segmental hypermobility after cervical arthroplasty: A possible pathomechanism for outcome failure

We present a 41-year-old man who underwent a cervical discarthroplasty (CDA) C5-6 procedure with an increase of the segmental range of motion from 2.8° to 6.9° and an increase in disc height from 5.8mm preoperatively to 10.4mm postoperatively with an unfavorable long-term clinical outcome. Both anterior cervical discectomy with fusion (ACDF), as well as CDA have been proven to be successful procedures in the management of cervical radiculopathy with good to excellent outcomes and low complication rates. The rationale for CDA over ACDF highlights the preservation of segmental motion and reduction of the incidence of adjacent segment disease. This case report suggests that a hypermobility syndrome and also an overcorrection of the cervical range of motion may be responsible for an unfavorable outcome after CDA.

Desmopression is an effective adjunct treatment for reversing excessive hyponatremia overcorrection

We report a case of a 50-year-old malnourished African American male with hiccups, nausea and vomiting who was brought to the Emergency Department after repeated seizures at home. Laboratory evaluations revealed sodium (Na⁺) 107 mmol/L, unmeasurably low potassium, chloride < 60 mmol/L, bicarbonate of 38 mmol/L and serum osmolality 217 mOsm/kg. Seizures were controlled with 3% saline IV. Once nausea was controlled with iv antiemetics, he developed large volume free water diuresis with 6 L of dilute urine in 8 h (urine osmolality 40-60 mOsm/kg) and serum sodium rapidly rose to 126 mmol/L in 12 h. Both intravenous desmopressin and 5% dextrose in water was given to achieve a concentrated urine and to temporarily reverse the acute rise of sodium, respectively. Serum Na⁺ was gradually re-corrected in 2-3 mmol/L daily increments from 118 mmol/L until 130 mmol/L. Hypokalemia was slowly corrected with resultant auto-correction of metabolic alkalosis. The patient discharged home with no neurologic sequaele on the 11^th hospital day. In euvolemic hyponatremic patients, controlling nausea may contribute to unpredictable free water diuresis. The addition of an antidiuretic hormone analog, such as desmopressin can limit urine output and prevent an unpredictable rise of the serum sodium.

Comparing the rate of regression after conductive keratoplasty with or without prior laser-assisted in situ keratomileusis or photorefractive keratectomy

Purpose:

To assess the regression rate of conductive keratoplasty (CK) in patients with or without previous laser-assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK).

Setting:

University of Utah, Medical School, John A. Moran Eye Center, Salt Lake City, Utah.

Materials and Methods:

A retrospective, age-matched chart review identified records of 6 patients who underwent CK after refractive surgery and 12 patients who underwent CK without prior refractive surgery. The main outcome measures were postoperative uncorrected and corrected visual acuities and refraction changes over time.

Results:

Preoperatively, the mean manifest refraction spherical equivalent (MRSE) of the 15 eyes (12 patients) that underwent CK without refractive surgery was 0.83 diopters (D) and the 7 eyes (6 patients) that underwent CK after refractive surgery had an average MRSE of 0.27 D. Postoperatively, the mean MRSE of the refractive surgery patients was -0.86 D at 6 months, regressing to -0.67 D at 12 months. The postoperative MRSE in the eyes without refractive surgery was -0.58 D. at 6 months, regressing to -0.38 D at 12 months. The rate of regression was linear in both groups, calculated at 0.033 D per month in all patients.

Conclusions:

Patients with previous LASIK or PRK showed a greater treatment response to CK but regressed at a similar rate as those eyes without prior LASIK or PRK. Overall CK is a safe procedure that inevitably regresses.