Regional Anesthesia in Upper-Limb Surgery.

BACKGROUND: Local and regional anesthesia is associated with numerous clinical and institutional advantages relative to general anesthesia. As anesthesiologists and surgeons increasingly integrate local and regional anesthesia into their clinical practice, an understanding of the principles, evolution, and trends underpinning modern anesthetic techniques continues to be relevant. METHODS: A review of the literature in databases Medline, PubMed, and EMBASE identified recent developments, ongoing trends, and historical milestones in upper-limb regional anesthesia. RESULTS: Advances in regional anesthetic techniques in the last century have led to reduced postoperative pain, improved safety, and improved outcomes in upper-limb surgery. The development of ultrasound-guided techniques, as well as pharmacological advances in local anesthetic drugs and adjuncts, has further advanced the role of regional anesthesia. Wide-awake local anesthesia with no tourniquet has allowed certain procedures to be performed on select patients in outpatient and low-resource settings. CONCLUSIONS: This review provides an overview of local and regional anesthesia in the upper-limb from its historical origins to its contemporary applications in upper-limb surgery, particularly during the COVID-19 pandemic.

Acute Mallet Finger Injuries-A Review.

Acute disruptions of the terminal extensor tendon are common and can result in significant dysfunction if not recognized and treated appropriately. This article provides a topical review of the contemporary literature concerning acute mallet finger injuries. It also proposes a modification to the Doyle classification to make it more encompassing and less prone to interobserver error.

The Volar Midline Longitudinal Groove of the Middle Phalanx: An Anatomic Study and Clinical Implications.

PURPOSE: To investigate the volar anatomy of the middle phalanges of the hand; in particular, to define the presence and depth of a volar midline longitudinal groove. METHODS: Measurements were performed at 5 equidistant points along the shafts of 60 skeletonized middle phalanges from 15 cadaveric hands. The thickness at the midline of each phalanx was subtracted from the maximal dorsovolar thickness to indicate the presence or absence of a groove at each point. The phalanges were also evaluated by computed tomography to confirm the presence of a volar groove and to rule out morphological abnormalities. RESULTS: A volar groove was confirmed in all 60 phalanges. The groove had an average depth of 0.4 mm and was found to be deepest at the mid-phalangeal shaft. The groove reached a depth of greater than 1 mm in 23% of the phalanges. The middle phalanges of the middle and ring digits consistently revealed deeper grooves than those found in the index and little fingers. Computed tomography confirmed the presence of a volar groove and showed no morphological abnormalities. CONCLUSIONS: A midline volar longitudinal groove is present in the middle phalanges, is most pronounced in the mid-phalangeal shaft, and is the deepest in the middle and ring fingers. CLINICAL RELEVANCE: Surgeons should be cognizant of the volar longitudinal groove when inserting screws from dorsal to volar during the fixation of middle phalangeal fractures. Lateral intraoperative fluoroscopy may not reveal excessive screw penetration because of the presence of ridges on either side of the groove. Particular care should be taken at the mid-phalangeal level of the middle phalanges of the middle and ring fingers.

Biomechanical Analysis of Abductor Pollicis Longus Lasso Suspensionplasty for Trapeziectomy.

PURPOSE: Multiple methods of ligament reconstruction and tendon interposition (LRTI) or suspension have been described to prevent first metacarpal subsidence following trapeziectomy. An abductor pollicis longus (APL) lasso is a newly described technique of suspensionplasty, which aims to obviate concerns regarding previously described methods. The purpose of this study was to compare subsidence between the APL lasso and 2 other common methods, APL sling and flexor carpi radialis LRTI, after trapeziectomy in cadaveric forearms. METHODS: Ten cadaveric forearms were prepared on a custom-made plinth to recreate pinch grip upon the loading of previously identified muscles. A sequence of procedures was performed, with radiographs taken after each to assess the subsidence. RESULTS: The APL lasso was superior to simple trapeziectomy and flexor carpi radialis LRTI in preventing subsidence. CONCLUSIONS: The APL lasso was superior to simple trapeziectomy and flexor carpi radialis LRTI in preventing subsidence, and it may be a viable alternative when considering suspension methods after trapeziectomy. CLINICAL RELEVANCE: The APL lasso may be considered when trying to prevent subsidence after trapeziectomy.

Sagittal Band Injuries: A Review and Modification of the Classification System.

Sagittal band injuries, although relatively uncommon, can be difficult to treat. This review provides a contemporary perspective on this pathology, as well as a modification to the classification system. This modification aims to incorporate the spectrum of disease seen, guide treatment, and allow standardization when documenting and describing injuries.

Free Medial Femoral Condyle Flap for Reconstruction of Scaphoid Nonunion: A Systematic Review.

BACKGROUND: The free medial femoral condyle (MFC) bone flap is an attractive option for reconstruction of scaphoid nonunion utilizing vascularized bone to augment bony healing, especially in cases of failed prior treatment or osteonecrosis. This review aims to determine the role and reliability of the free MFC flap for treatment of scaphoid nonunion. METHODS: A search of electronic databases was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Articles examining free MFC bone flaps for treatment of scaphoid nonunion were included for analysis. Outcomes of interest included flap failure, postoperative union rate, time to union, carpal indices, functional outcomes, and complications. RESULTS: Twelve articles met the inclusion criteria. A total of 262 patients underwent free MFC flaps for treatment of scaphoid nonunion. The most common site of nonunion was the proximal pole of the scaphoid with 47% of patients receiving prior attempts at operative management. Overall bony union rate was 93.4% with a mean time to union of 15.6 weeks. There were no flap failures reported. Improvements in carpal indices including scapholunate (p < 0.0004), radiolunate (p < 0.004), lateral interscaphoid angles (p < 0.035), and revised carpal ratio height (p < 0.024) were seen postoperatively. Visual analog scale improved postoperatively from 6.5 to 2.3 (p < 0.015). Postoperative complications were observed in 69 cases (26.3%), with 27 patients (10.3%) requiring further operative intervention. However, no major donor or recipient site morbidity was appreciated. CONCLUSION: MFC flaps provide a highly versatile and reliable option for reconstruction of scaphoid nonunion with excellent bony union rates and acceptable complication rates. The present literature suggests that MFC reconstruction of scaphoid nonunion restores radiocarpal anatomy and improves wrist function without causing significant donor or recipient site morbidity.

Reconstruction of an infected midshaft radius and ulna nonunion using a free vascularized fibula and medial femoral condyle flap.

Conventional grafts do not perform well in the treatment of large diaphyseal bone defects. Forearm nonunions are especially challenging due to complex biomechanical and kinematic demands. Free bone flaps may yield more predictable bony restoration in these cases, while keeping morbidity acceptable to the patient. We aim to illustrate one combination of flaps which can be used in these conditions. This article reports on a 23 year old patient with an 8 cm diaphyseal nonunion of the radius and a similar 7 cm defect of the ulna after infection of fracture fixation hardware. The radius was treated with a free fibular flap (FFF) and the ulna with a medial femoral condyle (MFC) flap in a staged procedure after initial debridement. The patient was followed up for 6 months without significant complications. Both flaps healed within 3 months, yet the MFC demonstrated faster bony incorporation. We attributed this to the spongious nature of the MFC flap compared to the thick cortical FFF. This case report hopes to illustrate one type of flap combination for extensive forearm bone defects. The selection and approach minimizes donor site morbidity to a single limb and possibly hastens bony union of the forearm.

Growth of the New Thumb Metacarpal After Pollicization for Thumb Hypoplasia.

PURPOSE: To investigate the radiographic length and width of the new thumb metacarpal in relation to the middle finger proximal phalanx; to assess the incidence of premature physeal closure of the new metacarpal; and to consider whether there is a relationship between growth characteristics and the presence of union or nonunion of the new trapezium to the retained index finger metacarpal base. METHODS: Forty pollicizations were assessed with preoperative or immediate postoperative radiographs and follow-up radiographs to establish the growth characteristics of the new thumb metacarpal. Functional outcomes comprising grip strength, pinch strength, and range of motion were correlated with radiological findings of presence or absence of open physes and presence or absence of union of the new trapezium to the metacarpal base. RESULTS: The new thumb metacarpal physis was open in 28 pollicizations and closed in 12. In the latter group, all physes of the hand had closed indicating skeletal maturity. The length and width indices of the new thumb metacarpal in relation to the middle finger proximal phalanx were equivalent to or greater than the perioperative growth indices. There was a reduced postoperative length ratio in those patients with nonunion of the new trapezium to the base of the metacarpal. There was no change in strength and range of motion parameters with growth other than that related to normal improvement with age. CONCLUSIONS: We are unable to demonstrate premature physeal closure following routine pollicization. The growth of the metacarpal continues in a normal manner to skeletal maturity. A failure of union of the new trapezium to the metacarpal base may compromise growth. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Effects of Removal and Reinsertion of Headless Compression Screws.

PURPOSE: This study investigates the loss of compression when 3 commonly used headless compression screws are backed out (reversed), and assesses the ability to re-establish compression with screws of greater diameter. METHODS: Two investigators tested 3 screw designs (Acutrak 2, Synthes HCS, Medartis SpeedTip CCS) in 2 diameters and lengths. Each design had 10 test cycles in a polyurethane foam bone model with compression recorded using a washer load cell. A 28-mm screw of the narrower diameter was inserted until 2 mm recessed and then reversed 30°, 60°, 90°, 180°, 270°, 360°, and 720°. After this the screw was removed completely and a 24-mm screw of greater diameter inserted until recessed 2 mm with the compressive force again recorded. RESULTS: All screws showed an immediate, statistically significant loss of compression at 30° of reversing. The Acutrak 2 Micro screw demonstrated not only the greatest mean compressive force, but also the fastest compressive loss. Insertion of the shorter screw of greater diameter was associated with re-establishment of compression to levels comparable with the original screw. CONCLUSIONS: This study reaffirms the importance of establishing the correct screw length before insertion due to the immediate loss of compression with reversal of these devices. CLINICAL RELEVANCE: If a headless compression screw penetrates the far joint surface, the screw should be completely removed and replaced with a shorter screw of greater diameter.

Simulation study of the effect of molar mass dispersity on domain interfacial roughness in lamellae forming block copolymers for directed self-assembly.

A coarse-grained molecular dynamics model was used to study the thin film self-assembly and resulting pattern properties of block copolymer (BCP) systems with various molar mass dispersities. Diblock copolymers (i.e. A-b-B type) were simulated in an aligned lamellar state, which is one of the most common patterns of potential use for integrated circuit fabrication via directed self-assembly of BCPs. Effects of the molar mass dispersity (Ð) on feature pitch and interfacial roughness, which are critical lithographic parameters that have a direct impact on integrated circuit performance, were simulated. It was found that for a realistic distribution of polymer molecular weights, modeled by a Wesslau distribution, both line edge roughness (LER) and line width roughness (LWR) increase approximately linearly with increasing Ð, up to ∼45% of the monodisperse value at Р= 1.5. Mechanisms of compensation for increased A-A and B-B roughness were considered. It was found that long and short chain positions were not correlated, and that long chains were significantly deformed in shape. The increase in LWR was due to the increase in LER and a constant correlation between the line edges. Unaligned systems show a correlation between domain width and local molecular weight, while systems aligned on an alternating pattern of A and B lines did not show any correlation. When the volume fraction of individual chains was allowed to vary, similar results were found when considering the Ð of the block as opposed to the Ð of the entire system.

Stability of the Basal Joints of the New Thumb After Pollicization for Thumb Hypoplasia.

PURPOSE: To investigate the presence or absence of union of the new trapezium to the retained metacarpal base after pollicization and to relate this to stability of the new trapezium and the new carpometacarpal joint. METHODS: Thirty-six patients (46 pollicizations) were assessed at clinical review. Mean time from surgery to review was 96 months (range, 9-260 mo). Clinical assessment measured range of motion (ROM) at the carpometacarpal joint, stability of the carpometacarpal joint, and extrinsic and intrinsic strength of both hands. Radiological review evaluated 3 parameters: bony union between the new trapezium and retained metacarpal base, stability of the new trapezium in relationship to the metacarpal base, and carpometacarpal joint stability. RESULTS: There was radiographic nonunion between the new trapezium and the retained metacarpal base in 8 (1 treated) of 46 pollicizations. Relative risk of instability of the new trapezium was 39 times more likely if nonunion was present. Nine pollicizations were unstable at the carpometacarpal joint, 8 in those with union and 1 with nonunion. Relative risk of instability was 1.4 times more likely for those with union. For patients with nonunion, ROM and grip strength variables were reduced but only grip strength reached statistical significance. In patients with carpometacarpal joint instability, ROM and grip strength variables were reduced but none of the variables reached statistical significance. CONCLUSIONS: This study suggests that when the surgeon is attempting to obtain union of the new trapezium to the retained metacarpal base, failure to do so results in a poorer thumb with a significantly increased risk of trapezial instability and decreased grip strength. There is a mildly increased risk of carpometacarpal joint instability with union, but significantly poorer function as a consequence of this has not been demonstrated. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

An assessment of 2 objective measurements of web space position.

PURPOSE: To describe 2 simple objective clinical methods of measuring the web position between fingers and to determine their intra-observer and inter-observer reliabilities. METHODS: Two observers examined the second, third, and fourth web spaces on both hands of 30 adult healthy volunteers. The web index measured the web height as a relative ratio to constant anatomical landmarks on both fingers subtending the web. The dorsal web index took reference from the distance between the metacarpophalangeal and proximal interphalangeal joints, whereas the palmar web index was measured in relation to the distance between the most proximal basal digital and proximal interphalangeal joint creases. The intraclass correlation coefficient was used to determine intra-observer and inter-observer reliability. RESULTS: Intraclass correlation coefficient values for intra-observer and inter-observer reliability were greater than 0.80, indicating excellent agreement. There was no statistically significant difference between the dorsal or palmar measurement methods in terms of reliability. CONCLUSIONS: The dorsal or palmar measurement method may be reliably used in healthy adults to establish a web index that describes the web position. The palmar method is considered easier to perform. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.

Carpal tunnel syndrome caused by an interosseous ganglion of the lunate.

We present a case of a 29-year-old woman with diffuse, unilateral wrist pain and carpal tunnel syndrome secondary to an interosseous ganglion of the lunate and aim to highlight uncommon aetiologies when assessing patients with atypical carpal tunnel symptoms.

Mobile garbage bins and hand injuries in older people.

OBJECTIVES: To conduct a database search, chart and literature review of open extensor tendon and proximal interphalangeal joint injuries incurred while handling mobile garbage bins. DESIGN, SETTING AND PARTICIPANTS: A review of medical records at a Sydney tertiary referral hospital and a NSW rural Level 2 trauma hospital from 1 January 2006 to 31 December 2010, identified through database searches of appropriate medical record codes and followed by a chart review. RESULTS: We identified 11 patients with finger injuries from handling mobile garbage bins that necessitated hospital-based treatments. Their average age was 75 years. Eight patients required surgery. Patients typically fell while maintaining their grip on mobile garbage bin handles, causing abrasive injury to the dorsal aspect of the proximal interphalangeal joint. CONCLUSIONS: Older patients are at risk of significant injuries to the dorsal side of their fingers when manoeuvring mobile garbage bins. This risk could be reduced by providing older members of the community with help to move their bins, or by modifying the design of bin handles. We propose a simple modification to the design of bin handles.

Higher extracellular fluid volume in women is concealed by scaling to body surface area.

OBJECTIVE: The objective was to assess body surface area (BSA) for scaling extracellular fluid volume (ECV) in comparison with estimated lean body mass (LBM) and total body water (TBW) across a range of body mass indices (BMI). METHODS: This was a multi-centre study from 15 centres that submitted raw data from routine measurement of GFR in potential kidney transplant donors. There were 819 men and 1059 women in total. ECV was calculated from slope-intercept and slope-only measurements of GFR. ECV was scaled using two methods: Firstly, division of ECV by the scaling variable (ratio method), and secondly the regression method of Turner and Reilly. Subjects were placed into five BMI groups: < 20, 20-24.9, 25-29.9, 30-34.9, and 35 + kg/m(2). LBM and TBW were estimated from previously published, gender-specific prediction equations. RESULTS: Ratio and regression scaling gave almost identical results. ECV scaled to BSA by either method was higher in men in all BMI groups but ECV scaled to LBM and TBW was higher in women. There was, however, little difference between men and women in respect to ECV per unit weight in any BMI group, even though women have 10% more adipose tissue. The relations between TBW and BSA and between LBM and BSA, but not between LBM and TBW, were different between men and women. CONCLUSION: Lean tissue in women contains more extracellular water than in men, a difference that is obscured by scaling to BSA. The likely problem with BSA is its insensitivity to body composition.

Classification of congenital anomalies of the hand and upper limb: development and assessment of a new system.

The Oberg, Manske, and Tonkin (OMT) classification of congenital hand and upper limb anomalies was proposed in 2010 as a replacement for the Swanson International Federation of Societies for Surgery of the Hand classification system, which has been the accepted system of classification for the international surgical community since 1976. The OMT system separates malformations from deformations and dysplasias. Malformations are subdivided according to the axis of formation and differentiation that is primarily affected and whether the anomalies involve the whole limb or the hand plate. This review outlines the development of classification systems and explores the difficulty of incorporating our current knowledge of limb embryogenesis at a molecular level into current systems. An assessment of the efficacy of the OMT classification demonstrates acceptable inter- and intraobserver reliability. A prospective review of 101 patients confirms that all diagnoses could be classified within the OMT system. Consensus expert opinion allowed classification of those conditions for which there is not a clear understanding of the mechanism of dysmorphology. A refined and expanded OMT classification is presented.

Outcomes of First Metacarpal Extension Osteotomy for Base of Thumb Arthritis.

BACKGROUND: First metacarpal extension osteotomy (FMEO) aims to correct the adduction deformity associated with thumb arthritis, as well as improve the congruity at the first carpometacarpal (FCMC) joint. However, the benefits of this procedure are currently unclear. The purpose of this study is to investigate the outcomes of FMEO in the treatment of FCMC joint arthritis. METHODS: Electronic databases were searched systematically for original data studies in the English language reporting outcomes following FMEO for base of thumb arthritis. Data were extracted from the text, tables, and figures of publications and meta-analyzed where possible. RESULTS: Ten publications comprising 211 thumbs were included. FMEO was associated with an improvement in pain relief and patient-reported functional outcomes, however meta-analysis showed no significant long-term improvement in grip strength or lateral pinch grip. Although there was disease progression in one third of patients after FMEO, most did not require further procedures. Outcomes following secondary procedures was not analyzed in the literature. FMEO produced a range of minor complications, however, major complications were rare. CONCLUSIONS: The available evidence suggests FMEO does not improve grip or pinch strength. However, it may have a role in analgesia and improvement in functional outcomes. Further studies should compare outcomes of FMEO to continued nonoperative treatment, or other surgical options including arthroscopy or ligamentous reconstruction.

The Medial Femoral Trochlea Osteochondral Flap for Scaphoid Reconstruction: A Systematic Review.

BACKGROUND: The medial femoral trochlea flap has been used to resurface scaphoids with recalcitrant proximal pole fractures or avascular necrosis, providing vascularized osteochondral tissue with similar morphological characteristics. This article aims to review the contemporary literature on its use for scaphoid reconstruction. METHODS: A systematic review of Embase, PubMed, Cochrane Central Register of Controlled Trials, and MEDLINE assessed the use of medial femoral trochlea flaps in scaphoids. RESULTS: Eight studies were included, with 76 patients at a mean age of 26 years. Forty-three patients underwent clinical review, and 10 patients underwent radiographic evaluation, at a mean 23.3 months of follow-up. Flaps were generally performed for proximal pole fractures, avascular necrosis, nonunion, or failure of prior fixation; 94.4% of the flaps united. No marked change in sagittal plane motion was noted; reductions were seen in axial and coronal plane motion. The Disabilities of the Arm, Shoulder, and Hand scores improved from a mean of 25.2 to 11.5. Radiographic markers also improved. A total of 12.3% of patients had unplanned return to theater. Three patients required early revision for vascular thrombosis, and 1 patient suffered a volar carpal dislocation. Three patients underwent salvage procedures for ongoing pain. CONCLUSIONS: Although technically demanding, promising early-term to medium-term results are noted with the use of medial femoral trochlea flaps in the scaphoid.

Clinical Outcomes and Complications of Primary Fingertip Reconstruction Using a Reverse Homodigital Island Flap: A Systematic Review.

BACKGROUND: Reverse homodigital island flaps (RHIFs) are increasingly used to reconstruct traumatic fingertip injuries, but there is limited evidence on the efficacy of this technique. We performed a systematic review of the literature to establish the safety and functional outcomes of RHIF for traumatic fingertip injuries. METHODS: Electronic searches were performed using 3 databases (PubMed, Ovid Medline, Cochrane CENTRAL) from their date of inception to April 2020. Relevant studies were required to report on complications and functional outcomes for patients undergoing RHIF for primary fingertip reconstruction. Data were extracted from included studies and analyzed. RESULTS: Sixteen studies were included, which produced a total cohort of 459 patients with 495 fingertip injuries. The index and middle fingers were involved most frequently (34.6% and 34.1%, respectively), followed by the ring finger (22%), the little finger (6.7%), and the thumb (2.6%). The mean postoperative static and moving 2-point discrimination was 7.2 and 6.7 mm, respectively. The mean time to return to work was 8.4 weeks. The mean survivorship was 98.4%, with the pooled complication rate being 28%. The pooled complication rate of complete flap necrosis was 3.6%, of partial flap necrosis was 10.3%, of venous congestion was 14.6%, of pain or hypersensitivity was 11.5%, of wound infection was 7.2%, of flexion contractures was 6.3%, and of cold intolerance was 17.7%. CONCLUSIONS: Reverse homodigital island flaps can be performed safely with excellent outcomes. To minimize complications, care is taken during dissection and insetting, with extensive rehabilitation adhered to postoperatively. Prospective studies assessing outcomes of RHIF compared with other reconstruction techniques would be beneficial.