The relationship between plate prominence and need for removal after volar plate osteosynthesis of distal radius fractures

PURPOSE

This study aimed to assess the incidence of plate-related complications and the need for plate removal after volar plate osteosynthesis of the distal radius in relation to Soong classification.

METHODS

All consecutive patients (age > 16 years) in our level II trauma center treated with plate osteosynthesis for distal radius fractures from January 2017 until June 2019 were retrospectively evaluated. The main outcome measures were volar plate positioning according to Soong classification and incidence of plate removal. In addition, the incidence of tendon ruptures, reasons for volar plate removal, and improvement of complaints after removal were evaluated.

RESULTS

The overall incidence of plate removal in the 336 included patients was 16.9% (n = 57). Removal incidence in Soong 2 plates (28.2%) was significantly higher compared to Soong 0 and 1 plates (8.0% and 14.4%, respectively), P = 0.003. Multivariable binary logistic regression analysis showed Soong grade 2 as an independent predictor for plate removal, OR 4.3 (95% CI 1.4-13.7, P = 0.013). Four cases of flexor and four cases of extensor tendon rupture were reported, all in Soong 2 grade plating. The main reasons for volar plate removal were pain (42%) and reduced functionality (12%). In cases where pain was the main reason for removal, 81% of patients reported a decrease in pain during follow-up after surgery.

CONCLUSIONS

This study suggests an association between plate prominence graded by Soong and plate removal using a single plating system. Plate prominence should be reduced in volar plating whenever technically feasible.

Zone II Flexor Pollicis Longus Repair: Thumb Flexion and Complications

Background: The aim of flexor pollicis longus (FPL) repair is to create a construct that is strong enough to withstand forces encountered during rehabilitation and to achieve an optimal active range of motion. The aim of this study was to: (1) assess factors influencing active thumb interphalangeal (IP) joint flexion; and (2) assess the factors associated with reoperation. Methods: Retrospectively, 104 patients with primary repair of a Zone II FPL laceration from 2000 to 2016 were identified. A medical chart review was performed to collect patient-, injury-, and surgery characteristics as well as the degree of postoperative active IP-flexion and occurrence of reoperation. Bivariate analyses were performed to identify factors influencing active IP-flexion and factors associated with reoperation. Results: The reoperation rate was 17% (n = 18) at a median of 3.4 months (range: 2.3-4.4). Indications for reoperation mainly included adhesion formation (n = 10, 56%) and re-rupture (n = 5, 28%). The median range of active IP-flexion was 30° (interquartile range [IQR]: 20-45) at a median of 12.4 weeks (IQR: 8.1-16.7). Solitary injury to the thumb (β = 17.9, P = .022) and the use of epitendinous suture (β = 10.0, P = .031) were associated with increased active IP-joint flexion. No factors were statistically associated with reoperation. Conclusions: About 1 in 5 patients undergo reoperation following primary repair of a Zone II FPL laceration, mostly within 6 months of initial surgery. The use of epitendinous suture is associated with greater active IP-flexion. Patients with multiple digits injured accompanying a Zone II FPL laceration have inferior IP-joint motion.

Computational investigation of possible inhibitors of the winged-helix domain of MUS81

The methyl methanesulfonate and ultraviolet sensitive 81 (MUS81) is a structure-specific endonuclease that is highly conserved in eukaryotes and essential for homologous recombination repair. The winged-helix domain at the N-terminus of MUS81 (wMUS81) can bind DNA substrates and regulate the endonuclease activity. The repression of MUS81 activity could enhance the sensitivity to antitumor compounds of different tumour cells. Thus, MUS81 is a potential therapeutic target in cancer therapy. However, specific inhibitors of MUS81 have remained elusive. Here, for the first time, we attempt to discover the compounds disrupting the wMUS81 activity. The binding affinity of available drugs to wMUS81 was first estimated by molecular docking. pK_a values were taken into consideration to eliminate unlikely protonation states of the ligands. Top-lead compounds were then estimated the binding affinity using the fast pulling ligand simulations. Finally, the free energy perturbation method accurately defined the absolute binding free energy of the top four ligands, revealing the most potential inhibitors of wMUS81 including simeprevir and nilotinib. Binding of simeprevir destabilizes the β-hairpin region of wMUS81, likely disturbing the wMUS81 function. The van der Waals free binding energy majorly modulates the ligand-binding mechanism. The two conserved residues Leu189 and Arg196 are likely important in monitoring the interacting process of simeprevir to wMUS81.

Clinico-epidemiological investigation of feline panleukopenia and parvoviral enteritis in the two largest pet hospitals in Bangladesh

Objective:

A clinico-epidemiological study was conducted at two veterinary hospitals in Dhaka to evaluate the prevalence of parvoviral enteritis (PVE) in dogs and feline panleukopenia (FPL) in cats, to detect factors associated with them, and to identify their common clinical signs.

Materials and Methods:

Clinico-epidemiological data were collected for a total of 88 dogs and 129 cats which were presented to the hospitals, entered into MS excel 2010, and then transferred to STATA-14 software for conducting descriptive and univariable statistical analyses (Fisher’s exact test). The maps showing the spatial distribution of PVE and FPL were produced by using QGIS software version 2.18.13.

Results:

PVE in dogs and FPL in cats had the highest prevalence compared to other diseases (34.1%; 95% confidence interval: 24.3–44.9; N = 88 and 20.2%; 95% confidence interval: 13.6–28.1; N = 129, respectively). Young age (43.8%), poor body condition (58.4%), and exotic breeds (44.2%) were significantly associated with the occurrence of PVE (p ≤ 0.05). Poor body condition (27.8%) and non-vaccination status (26.7%) were associated with FPL (p ≤ 0.05). Both PVE and FPL showed clinical signs of being off-feed, frequent vomiting, weakness, and moderate dehydration.

Conclusion:

The high prevalence of PVE and FPL indicates that they are common in dogs and cats in Dhaka, Bangladesh. The factors related to PVE are young age, exotic breed, and poor body condition score (BCS), and FPL are poor BCS and non-vaccination. Specific measures such as care during younger age, good nutrition, and routine vaccination are needed to prevent and control PVE and FPL in Dhaka’s dog and cat population.

Subcutaneous Transposition of the Flexor Pollicis Longus: Does It Provide Increased Length for Tendon Repair? A Cadaveric Study

Background: Flexor pollicis longus (FPL) tendon lacerations typically occur via sharp mechanisms such as knife injury. When the injury is chronic, it may be difficult to perform a tension free repair, and tendon lengthening may be required. This article proposes a technique that transposes the proximal tendon stump over the thenar eminence subcutaneously, out of the carpal tunnel, in an attempt to gain additional tendon length by eliminating the sharp turn the FPL takes. Methods: A total of 17 cadaveric hands were used. The FPL tendon was identified and affixed to soft tissue in the distal forearm as well as at the thumb metacarpophalangeal (MP) joint with hypodermic needles. The tendon was then transected at the level of the MP joint of the thumb, removed from the carpal tunnel, and transposed on top of the thenar eminence to reach where it had been transected. The length gained by transposing the tendon was recorded by measuring the overlap of the tendon ends at the MP joint. Results: The mean amount lengthened was 7.6 mm with a standard deviation of 2.4 mm, ranging from as little as 5 mm to as high as 13 mm. Conclusions: To our knowledge, transposition of FPL tendon is a novel technique that has not been reported. Based on our cadaveric study, it can be used to bridge gaps between approximately 5 mm and 10 mm. Clinically, this amount of gap could potentially be more easily managed by simply making the repair tighter than usual as opposed to transposing the tendon.

Estimating the ligand-binding affinity via λ-dependent umbrella sampling simulations

The umbrella sampling (US) approach has been demonstrated to be a very efficient method for estimating the ligand-binding affinity. However, most of the calculated values overestimate experimental ones that are probably caused by the inaccurate representation of the interaction between the ligand and the surrounding molecules. The issue can be resolved via the implementation aspects of λ-alteration simulation into the US approach, which we call the λ-dependent umbrella sampling (λUS) scheme. In particular, the electrostatic and van der Waals interactions were simultaneously changed by using the coupling parameter λ during λUS simulations. The mean value of obtained results, ∆ G US λ = 0.20 = - 11.59 ± 1.51 kcal mol^-1 , is in good fitting to the mean value of respective experiments, ∆G_EXP =  - 11.26 ± 0.89 kcal mol^-1 . Moreover, the correlation between the proposed approach and experiment is quite good with a value of R US λ = 0.20 = 0.82 ± 0.10 . The λUS scheme significantly enhances the calculated accuracy since the RMSE of the proposed scheme is smaller than traditional US simulations, RMSE US λ = 0.20 = 2.99 ± 0.82 kcal mol^-1 versus RMSE US λ = 0.00 = 5.48 ± 0.81 kcal mol^-1 . Furthermore, the precision is increased since the computed error via λUS approach, δ US λ = 0.20 = 1.51 kcal mol^-1 , was smaller than those of the US simulation, δ US λ = 0.00 = 1.78 kcal mol^-1 . Overall, the proposed approach perhaps provides an efficient way to accurately and precisely estimate the ligand-binding free energy.

Pronator quadratus repair after volar plate fixation in distal radial fractures: evaluation of the clinical and functional outcome and of the protective role on the flexor tendons-a randomized controlled study

The objective was to evaluate pronator quadratus (PQ) repair following volar plating of distal radial fractures on clinical and functional outcome, as well as flexor tendon friction, during the first 12 months in ideally positioned plates (Soong 0). Confounding factors like variation in plate positioning, anatomical consolidation of the fracture and associated lesions were excluded. Eighty patients were included with distal radius fractures treated by volar locking plate in Soong grade 0 position, who were randomized to group PQ repair and group no repair. Sixty-five patients completed the 1-year follow-up: group PQ repair (n = 35) and group no repair (n = 30). Primary outcomes included range of motion, grip strength, pain level and QuickDASH. Secondary outcomes included distance between flexor pollicis longus (FPL) and volar rim and the largest distance between FPL and plate (soft tissue thickness occupied by PQ), assessed by ultrasonography. Mobility, grip strength and QuickDASH revealed no significant differences, except extension was significantly higher only in first 3 months and radial deviation was significantly higher only at 6 weeks after PQ repair. Pain level was significantly lower after PQ repair only in the first 3 months. Distance between FPL and volar rim and the largest distance between FPL and plate were significantly higher after PQ repair. No friction contact between FPL and volar rim was measured in both groups at all measurement moments. Consequently, protective flexor tendon effect of PQ repair could consequently not be concluded. In conclusion, clinical and functional short term benefits, except improved wrist extension and reduced pain in the first 3 months, were not proven in this study. In Soong grade 0, PQ repair is probably not necessary to prevent flexor tendon pathology. In Soong grade 1 or 2, this is still to be investigated. LEVEL OF EVIDENCE: 2.

Clinical and ultrasonographical follow-up after standard removal of distal radius volar plates positioned distal to the watershed line

Marginal fracture types of the distal radius may require volar plate positioning distal to the watershed line. Subsequently, plate prominence with direct friction with the flexor tendons occurs which is associated with flexor tendon pathology. Standard plate removal can be proposed. This cohort study examined clinical outcome, patient satisfaction and ultrasonographical assessment of the relation of the flexor pollicis longus (FPL) and the volar rim after standard plate removal. Twenty patients with volar plate prominence after osteosynthesis for distal radius fractures were included. Plate removal was performed at least 4 months after initial surgery. The mean age was 60 years (range 39-84). The average delay from hardware removal to assessment was 2.9 years (range 1.0-5.0 years). Mean flexion, extension and radial deviation were significantly decreased (p < 0.05) compared to the contralateral side, while ulnar deviation, pro- and supination and grip strength were not. Mean QuickDASH score was 21.5. 85% of patients described their result as good to excellent. 80% would undergo the intervention again. During ultrasonography, distance from FPL to volar rim remained significantly decreased compared to the uninjured side in neutral and flexed position (p < 0.05) despite plate removal. The largest distance between the FPL and the volar cortical bone, which is mainly occupied by the pronator quadratus, did not differ. In this study, the range of motion and FPL distance to the distal radius normalized only partially compared to the uninjured wrist after standard plate removal.

Flexor pollicis longus (FPL) tendon hypoplasia: A case report and literature review

An 18-year-old female presented with long-standing inability to flex her left thumb. MRI of the left thumb revealed flexor pollicus longus (FPL) tendon hypoplasia, and subsequent ultrasound of the bilateral thumbs confirmed a left-sided hypoplastic FPL tendon. Structural integrity of the left FPL tendon was confirmed during surgical examination under anesthesia. Multiple congenital anomalies of the FPL have been described, but FPL tendon hypoplasia and its appearance on imaging are rarely reported. This case demonstrates the diagnosis of FPL tendon hypoplasia on MRI, ultrasound, and surgical examination under anesthesia; and demonstrates the importance of including this entity in the differential diagnosis for impaired thumb flexion.

Bilateral anterior interosseous nerve syndrome with 6-year interval

Flexor pollicis longus paralysis related to idiopathic anterior interosseous nerve syndrome is well known, but few reports exist on bilateral disease. A 24-year-old man with no personal or family history of neurological disease developed isolated total loss of active flexion of the right thumb's interphalangeal joint after undergoing a wrist arthroscopy. Surgical exploration 5 weeks after onset showed flexor pollicis longus tendon to be intact; anterior interosseous nerve decompression was done with no abnormalities found. Because of persistent paralysis, electromyography was performed showing findings consistent with anterior interosseous nerve syndrome. After 7 months without recovery, the patient underwent tendon transfer. After 6 years, the patient presented with left-sided isolated flexor pollicis longus paralysis and electromyography indicated anterior interosseous nerve syndrome. Examination 9 months after onset showed persistent complete flexor pollicis longus paralysis but by 15 months spontaneous complete recovery had occurred. Anterior interosseous nerve syndrome can occur bilaterally and is likely to resolve completely without intervention but recovery may take longer than a year.

Disorders of consciousness and disordered care: families, caregivers, and narratives of necessity

By their nature, care decisions for patients with severe disorders of consciousness must involve surrogates. Patients, so impaired, have lost their decision-making capacity and the ability to direct their own care. Surrogates-family members, friends, or other intimates-must step in and make decisions about ongoing care or its withdrawal. This article shares the narrative experiences of these surrogate decision makers as they encounter the American health care system and accompany patients from injury through rehabilitation. Through their perspectives, the article considers challenges to ongoing care and rehabilitation that are a function of a prevailing medical infrastructure and reimbursement framework better suited to patients with acute care needs. Specific attention is paid to the ethical challenges posed by reimbursement strategies such as "medical necessity" as well as those proposed for the Affordable Care Act. The argument concludes that when it comes to care for a disorder related to consciousness, its provision is not discretionary, and its receipt is not an entitlement but a civil right.

Nerve transfer strategies for spinal cord injury

BACKGROUND

Spinal cord injury (SCI) is a devastating condition, which beleaguers its victims with long-term health issues. Nerve transfer is a feasible option for restoration of critical limb function in patients with SCI that potentially improves independence and quality of life.

METHODS

This article delineates the general principles of nerve transfer and its specific application pertinent to SCI. The available nerve transfer strategies are described based on the targeted limb function, mostly involving critical upper extremity function. The role of nerve transfer for paraplegia, diaphragm reanimation, and bladder reinnervation is also discussed.

RESULTS

Nerve transfer offers several advantages over the traditionally used tendon transfer.

CONCLUSIONS

Nerve transfer does not require prolonged immobilization and provides greater functional gain for a given transfer. Reconstruction of several facets of upper limb function potentially can be performed in a single stage. The merits of nerve transfer deserve further study to evaluate its value for spinal cord injury in humans.