Pronation on weightbearing radiographs does not correlate with pronation from weightbearing CT scans

IntroductionIn hallux valgus (HV), first metatarsal pronation is increasingly recognized as an important aspect of the deformity. The purpose of this study was to compare pronation in HV patients determined from the shape of the lateral head of the first metatarsal on AP weightbearing radiographs with pronation calculated from weightbearing CT (WBCT) scans.MethodsPatients were included in this study if they had preoperative and 5-month postoperative WBCT scans and corresponding weightbearing AP radiographs of the affected foot. Pronation of the first metatarsal on WBCT scans was measured using a 3D CAD model and the alpha angle and categorized into four groups on radiographs. Association between pronation groups on radiographs and WBCT scans was determined using Spearman correlation coefficients (r_s) and by comparing mean WBCT pronation of the first metatarsal between plain radiograph pronation groups.ResultsAgreement between the two observers’ pronation on radiographs was good (k = 0.634) and moderate (k = 0.501), respectively. There was no correlation between radiographic pronation and the 3D CAD model (r_s < 0.15). Preoperatively, there was weak correlation between the alpha angle and the radiographic pronation groups (r_s = 0.371, P = 0.048) although this relationship did not hold postoperatively (r_s = 0.330, P = 0.081). There was no difference in mean pronation calculated on WBCT scans between the plain radiographic groups.ConclusionPronation of the first metatarsal measured on weightbearing AP radiographs had moderate interobserver agreement and was only weakly associated with pronation measured from WBCT scans. These results suggest that first metatarsal pronation measured on weightbearing radiographs is not a substitute for pronation measured on WBCT scans.Level of evidenceIII, retrospective cohort study.     

Can we correct first metatarsal rotation and sesamoid position with the 3D Lapidus procedure?

ObjectiveWe examine the technique and radiographic outcomes obtained with triplanar first tarsometatarsal arthrodesis (3D Lapidus) for the surgical correction of hallux valgus (HV). This procedure, apart from correcting angular deformity 1st–2nd intermetatarsal angle, HV angle, etc., is specifically intended to act on first ray pronation and place the sesamoids in their normal position, to alleviate the metatarsalgia often occurring in HV before and after surgery, possibly caused by their abnormal position.This study aims to examine the radiographic outcomes of the 3D Lapidus procedure.Materials and methodsRetrospective study of 37 feet operated on from April 2019 to December 2019, with a minimum 1-year follow-up (mean 420 days), using the 3D Lapidus procedure. Radiographic outcomes were evaluated.ResultsThe intermetatarsal angle decreased from a mean value of 16.42° to 5.62° (p < 0.0001). The HV angle decreased from a mean value of 32.12° to 8.05° (p < 0.0001). The preoperative first metatarsocuneiform angle, with a mean value of 21.86°, was null after arthrodesis (p < 0.0001). The tibial sesamoid position, according to the Hardy and Clapham classification, decreased from a mean value of 4.84 to 1.27 after surgery, within normality (p < 0.0001).DiscussionCorrection of the deformity in a single plane is generally insufficient. It is necessary to act on the three planes of space to correct the deformity, obtain good outcomes, and avoid recurrence.ConclusionsRadiographic outcomes of triplanar correction with the 3D Lapidus procedure are excellent, achieving statistically significant differences in all parameters studied.     

A cone beam CT based 3D-assessment of bony forefoot geometry after modified Lapidus arthrodesis

BackgroundModified Lapidus arthrodesis (MLA) is a well-established treatment modality for hallux valgus deformities (HVD) associated with instability of the first ray. Although the three-dimensional (3D) nature of HVD has long been recognized, diagnostics still focus on plain radiographs. The objective of this study was to validate 3D Cone Beam CT (CBCT) in the perioperative assessment of HVD with focus on the alignment of the forefoot.MethodsIn a prospective clinical study, MLA was performed on 30 patients (25 females, 5 males; mean age: 63.2 years). Pre- and postoperatively standard radiographs and CBCT with full weight-bearing were acquired. For the CBCT based assessment, reproducible criteria have been defined, measured, and correlated with established radiological indicators.ResultsEvaluation of standard radiographic parameters (hallux-valgus angle [HVA], intermetatarsal angle 1-2 [IMA 1-2], distal metatarsal articular angle [DMAA], tibial sesamoid position [TSP]) showed significant improvement postoperatively. Comparison of measurements obtained from plain radiographs and CBCT were significantly correlated between both measuring techniques, indicating high reliability. Pronation of the first metatarsal and the sesamoids were significantly reduced by the procedure. Due to this repositioning effect, the second metatarsal head was elevated by 3.1 mm, and the lateral sesamoid was lowered by 3.8 mm. However, there was no correlation between the amount of pronation and conventional radiographic measures.ConclusionsCompared to plain radiographs, CBCT allows a more detailed view of the forefoot alignment in the coronal plain after MLA. MLA was able to recenter the sesamoids under der first metatarsal head and conversely led to elevation of the second metatarsal head.     

An electromyographic study of the effect of hand grip sizes on forearm muscle activity and golf performance

The study describes the differences in surface electromyography (EMG) activity of two forearm muscles in the lead and trail arm at specific phases of the golf swing using a 7-iron with three different grip sizes among amateur and professional golfers. Fifteen right-handed male golfers performed five golf swings using golf clubs with three different grip sizes. Surface EMG was used to measure muscle activity of the extensor carpi radialis brevis (ECRB) and flexor digitorum superficialis (FDS) on both forearms. There were no significant differences in forearm muscle activity when using the three golf grips within the group of 15 golfers (p > 0.05). When using the undersize grip, club head speed significantly increased (p = 0.044). During the backswing and downswing phases, amateurs produced significantly greater forearm muscle activity with all three grip sizes (p < 0.05). In conclusion, forearm muscle activity is not affected by grip sizes. However, club head speed increases when using undersize grips.     

A novel radial forearm free flap design to treat pharyngoesophageal stenosis in combination with the posterior wall of the trachea

Pharyngoesophageal stenosis (PES) is a common and serious complication of head and neck cancer treatments such as radiation therapy, chemotherapy, tracheoesophageal puncture placement, and total laryngectomy surgery. Dilation-resistant stenosis requires surgical reconstruction, often with a radial forearm free flap (RFFF). With the present technique, the authors refine their previous bipaddled free flap design used to reconstruct a persistent tracheoesophageal fistulae (TEF) in combination with PES. Accordingly, we present a novel bipaddled triangular RFFF design ideally suited to address the shape of the defect in the posterior tracheal wall that results when the TEF is opened and the esophageal and tracheal components are restored.     

Forearm fracture dislocations

Foerearm stability is provided by a complex interplay of the bony and osseo-ligamentous structures which constitute the forearm unit. Consequently, fractures of the radius and/or ulna with concurrent injuries to the stabilizing ligamentous structures can lead to chronic instability and dysfunction if treated incorrectly. Seen in both the adult and paediatric populations, correct diagnosis and management are essential to prevent long-term forearm pain and instability. This article covers the three main instability pattern injuries of the forearm with a focus on anatomy, biomechanics and surgical principles of acute and chronic reconstruction.     

Are hand biomechanics affected following radial forearm flap harvest? A systematic review and meta-analysis

Donor site morbidity following radial forearm flap (RFF) harvest remains a controversial issue. The aim of this meta-analysis was to answer the question “Are the range of wrist movements (range of motion, ROM) and hand strength affected after RFF harvesting?” The PubMed, Embase, Scopus, and Cochrane Library electronic databases were systematically searched (to December 2019). Self-controlled studies evaluating hand biomechanics after RFF harvest were included. Weighted mean differences with 95% confidence intervals were calculated using the random-effects model. The outcome variables were ROM, forearm movements, grip, and pinch strengths. Thirteen studies involving a total of 335 patients were included. With the exception of grip strength and supination, which showed statistically significant reductions of about 2.40 kg and 2.86° (P < 0.05), all other ROM, forearm movements, and pinch strengths showed an insignificant difference when the operated hand was compared to the non-operated hand (P > 0.05). Regression analysis showed that the method of donor site closure and size of the donor site defect had an insignificant impact on hand biomechanics. This study confirms the lack of discernible biomechanical morbidity after RFF transfer. The minimal reduction in hand biomechanics after RFF is considered to be clinically negligible.     

Extraordinary grip strength and specialized myology in the hyper‐derived hand of Perodicticus potto?

Previous behavioral reports of the African lorisid, Perodicticus potto, have speculated that these animals have an extraordinary grip strength. This ability is hypothesized to be facilitated by a range of anatomical features within the forelimb, ranging from the presence of a retia mirabilia in its wrist to the hyper‐abduction of its pollex. Despite numerous behavioral reports, however, this claim of extraordinary grip strength has not been empirically substantiated. This study quantifies the physiological cross‐sectional area of the digital flexor muscles within P. potto. These data are compared with a broad primate sample, including several similarly sized strepsirrhines. Contrary to expectation, we found that P. potto actually has relatively below‐average digital flexor PCSA. However, we identified other myological characteristics in the upper limb of P. potto that were unexpected, including the largest brachioradialis muscle (an elbow flexor) among our primate sample, and – despite P. potto having only a vestigial second digit – an independent digital extensor indicis that is absent in almost a quarter of our primate sample.