Clinical outcomes of reposition flap transfer for fingertip amputation

PURPOSE

This study aimed to describe the reposition flap for reconstructing fingertip amputation when replantation is not possible.

METHODS

This study retrospectively reviewed the records of patients with reposition flap transfers and investigated postoperative clinical outcomes and patient satisfaction. Sixteen patients with fingertip amputations treated with a reposition flap from 2016 to 2020. The mean age at injury was 46 years (range, 26-70 years). Ten cases were treated with oblique triangular advancement flaps, 3 with retrograde-flow digital artery flaps, and 3 with thumb palmar advancement flaps. Postoperative outcomes, including wound healing period and the IP/PIP extension angle, and the presence of grafted bone absorption and patient satisfaction were evaluated as of 3 years after surgery.

RESULTS

The average reduction in passive extension angle of the IP/PIP joint was 19°. The average time for complete wound healing was 28 days (range, 18-41 days). The reduction in passive extension angle of the IP/PIP joint was significantly correlated with the wound healing period (r = 0.66, p = 0.01). The absorption of the grafted bone was observed in 3 cases. In these cases, the distal tip of the flap became thin due to flap retraction and an insufficient flap volume. All patients were highly or fairly satisfied with the results of surgery.

CONCLUSION

Our findings show that IP/PIP flexion contracture can occur due to delayed wound healing after reposition flap transfer, but the patient satisfaction level was generally high. Therefore, reconstruction using a reposition flap gives acceptable clinical outcomes and high patient satisfaction as a result of medium to long-term.

Arthroscopically Assisted Treatment of Isolated Comminuted Trapezium Fracture: A Report of Two Cases

CASES

Two competitive athletes with isolated comminuted trapezium fractures, sustained during American football and rugby, presented with pain and swelling of the first metacarpal base. Computed tomography confirmed isolated comminuted trapezium fractures. Arthroscopic reduction of displacement with screw fixation below the articular surface was performed through a small incision. Both patients returned to their preinjury sports levels within 2 months postoperatively.

CONCLUSION

Arthroscopic treatment of isolated comminuted trapezium fractures achieved accurate reduction of articular surface displacement and preserved trapeziometacarpal joint stability with minimal soft-tissue invasion. This facilitated an early return to contact sports for the affected athletes.

Anatomical quantitative evaluation of popliteal artery visualization during medial approach in supine position

PURPOSE

The medial approach to the popliteal artery has been less commonly used than the posterior approach in surgical repair of traumatic popliteal injury. This study was performed to quantitatively evaluate the visual field of the popliteal artery obtained by staged myotendotomy in the medial approach to the popliteal artery.

METHODS

Twenty legs of fresh-frozen adult cadavers were dissected using the medial approach to the popliteal artery. In stage 1, the popliteal artery was exposed between the vastus medialis and sartorius muscles without myotendotomy. In stage 2, the medial head of the gastrocnemius muscle was dissected. In stage 3, the tendons of the sartorius and semimembranosus muscles were dissected. In stage 4, the tendons of the gracilis and semitendinosus muscles were dissected to fully expose the popliteal artery. The length of the popliteal artery that could be visualized in each stage was measured.

RESULTS

The anatomical length of the popliteal artery from the hiatus of the adductor magnus to the tendinous arch of soleus muscle ranged from 15 to 20 cm (mean, 16.3 cm). On average, 45%, 59%, 72%, and 100% of the popliteal artery were visualized in stage 1, 2, 3, and 4, respectively.

CONCLUSIONS

The medial approach to the popliteal artery has the advantage of being performed in the supine position, but it requires multiple myotendotomies around the knee. The results of this study may serve as a reference for myotendotomy depending on the site of injury to the popliteal artery.

Arthroscopy-Assisted Surgery for Trapeziometacarpal Osteoarthritis

Background: Functional outcomes of patients who underwent arthroscopy-assisted surgery for trapeziometacarpal osteoarthritis were reported. Methods: We included 24 consecutive patients (6 males and 18 females) who underwent surgery and postoperative hand therapy at our hospital between April 2012 and March 2018. For functional evaluation, we used the Purdue Pegboard Test (PPT), grip and pinch strength, range of motion of the thumb, visual analogue scale (VAS) for thumb pain, Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Japanese version of the Patient-Rated Wrist Evaluation (PRWE-J) preoperatively and 3 months postoperatively. Results: The mean PPT rating improved from 12.3 to 13.3, the VAS score from 51 to 16, the QuickDASH score from 48 to 30 and the PRWE-J score from 55 to 29. All the improvements were statistically significant. There was a moderate positive correlation between the magnitude of improvement in PPT and QuickDASH scores. Conclusions: Arthroscopic intervention and associated hand therapy were effective in achieving early postoperative relief of thumb pain and in improving hand dexterity and activities of daily living. Level of Evidence: Level IV (Therapeutic).

Anatomical Relations of the Perforators from the Descending Lateral Femoral Circumflex Artery and Vastus Lateralis Motor Nerve Branches

Background

The anterolateral thigh (ALT) flap, which is nourished by perforators from the descending branch of the lateral femoral circumflex artery (P), is one of the most commonly used flaps in soft tissue reconstruction. With the growing use of ALT flaps, attention toward donor-site morbidity has increased in recent years. Damage to the motor nerve branches of the vastus lateralis muscle (N) is one of the causes of donor-site morbidity, particularly muscle weakness. This study investigated the anatomical locations of the P and N in fresh-frozen cadaveric specimens.

Methods

This study included 43 cadaver limbs. A silicone rubber compound (30 mL) was injected into the femoral artery to visualize the vessel. The locations of the P and motor points of N were measured to assess the risk of N injury during ALT flap harvesting.

Results

There were one to six (mean, 2.7) P and two to seven (mean, 4) N. When the two most proximal perforators were used for flap harvesting, an average of 1.5 motor nerve branches (42%) was damaged because transection of the motor nerve branches was required for flap harvesting. In 33% of the limbs, only one motor nerve branch remained after the flap harvest. However, there were no cases where all motor nerve branches were severed.

Conclusion

When an ALT flap with two perforators is harvested, weakness of the vastus lateralis muscle may occur in cases with a small number of motor nerve branches.

Reliability and Validity Analysis of the Distal Radioulnar Joint Ballottement Test

PURPOSE

Triangular fibrocartilage complex injuries can cause distal radioulnar joint (DRUJ) instability, which can be evaluated clinically with the DRUJ ballottement test. However, the reliability and validity of the test are unclear. This study aimed to analyze the reliability and validity of the test using a tracking device on healthy participants and patients with triangular fibrocartilage complex injuries.

METHODS

In this cross-sectional study, three orthopedic hand surgeons performed the DRUJ ballottement test using a technique of holding the carpal bones to the radius on 25 healthy participants (50 hands; 10 men and 15 women; mean age, 33 years; range, 20-51 years) and eight patients with triangular fibrocartilage complex injuries (16 hands; six men and two women; mean age, 43 years; range, 27-59 years). We used a three-dimensional electromagnetic tracking device to quantify the movement of the DRUJ and verify the reliability and validity of the test.

RESULTS

The intrarater and interrater intraclass correlation coefficients for DRUJ movement were 0.77 and 0.61, respectively, and the kappa coefficient for grading of DRUJ instability was 0.79. The correlation coefficient between DRUJ movement measured using the tracking device and instability judged clinically was 0.77. A comparison of healthy participants and the patients showed significantly greater DRUJ movement in the patients.

CONCLUSIONS

The test showed substantial intrarater and interrater reliability for assessing DRUJ movement and instability. The significant positive correlation between DRUJ movement and instability indicates the concurrent validity of the test. Moreover, the test showed discriminative validity in identifying mild or moderate DRUJ instability.

CLINICAL RELEVANCE

The DRUJ ballottement test using the holding technique has a relatively high diagnostic accuracy and can be used to assess DRUJ instability.

Dynamic analysis of the ulnar nerve and cubital tunnel morphology using ultrasonography: a cadaveric study

BACKGROUND

The causes of ulnar neuropathy at the elbow are unclear. The authors hypothesized that the humeral trochlea protrudes into the cubital tunnel during elbow flexion and causes a dynamic morphologic change of the ulnar nerve in the cubital tunnel.

METHODS

An ultrasonic probe was fixed to the ulnar shafts of 10 fresh cadavers with an external fixator, and dynamic morphology of the cubital tunnel and ulnar nerve was observed. The distance from the Osborne band to the trochlea (OTD), distance from ulnar nerve center to the trochlea (UTD), and the short- and long-axis diameters of the nerve at 30°, 60°, 90°, and 120° of elbow flexion were recorded. We compared the OTD, UTD, and the flattening of the ulnar nerve at the different angles of flexion using single-factor analysis of variance. Correlation between the ulnar nerve flattering, OTD, and UTD was examined using Spearman correlation coefficient. A P value less than .05 was used to denote statistical significance.

RESULTS

Flattening of the ulnar nerve progressed with increasing elbow flexion and was significantly different between 0° and 60°, 90°, and 120° (P = .03 at 60°, P < .01 at 90° and 120°). OTD decreased with elbow flexion, and there was a significant difference at all elbow flexion angles (all P < .01). UTD decreased significantly from 0° flexion to 90° flexion (P = .03). Flattening of the nerve was significantly correlated with the OTD (r = 0.66, P < .01).

CONCLUSIONS

A positive correlation was found between the protrusion of the humeral trochlea into the cubital tunnel during elbow flexion and ulnar nerve flattening using cadaveric elbow and ultrasonography.

Simultaneous Bilateral Chronic Volar Lunate Dislocation: A Case Report

CASE

A 24-year-old professional judo competitor suffered injuries to both the wrists when he fell on his back while lifting a 90-kg barbell in the bilateral dorsiflexed wrist position. Simultaneous bilateral volar lunate dislocation had been missed for a year. The degenerated lunates were simultaneously removed using a palmar approach. At 12 months postoperatively, the patient returned to judo competitions without pain. Radiography showed no progression of the intercarpal alignment abnormality.

CONCLUSION

Simultaneous bilateral chronic volar lunate dislocation is extremely rare. Long-term follow-up is necessary to check for carpal alignment.

Acromioclavicular joint instability on cross-body adduction view: the biomechanical effect of acromioclavicular and coracoclavicular ligaments sectioning

Background

The acromioclavicular (AC) and coracoclavicular (CC) ligaments are important stabilizers of the AC joint. We hypothesized that AC and trapezoid ligament injuries induce AC joint instability and that the clavicle can override the acromion on cross-body adduction view even in the absence of conoid ligament injury. Accordingly, we investigated how sectioning the AC and CC ligaments contribute to AC joint instability in the cross-body adduction position.

Methods

Six fresh-frozen cadaveric shoulders were used in this study, comprising five male and one female specimen, with a mean age of 68.7 (range, 51–87) years. The left side of the trunk and upper limb, and the cervical and thoracic vertebrae and sternum were firmly fixed with an external fixator. The displacement of the distal end of the clavicle relative to the acromion was measured using an electromagnetic tracking device. We simulated AC joint dislocation by the sequential resection of the AC ligament, AC joint capsule, and CC ligaments in the following order of stages. Stage 0: Intact AC and CC ligaments and acromioclavicular joint capsule; stage 1: Completely sectioned AC ligament, capsule and joint disc; stage 2: Sectioned trapezoid ligament; and stage 3: Sectioned conoid ligament. The superior clavicle displacement related to the acromion was measured in the horizontal adduction position, and clavicle overriding on the acromion was assessed radiologically at each stage. Data were analyzed using a one-way analysis of variance and post-hoc tests.

Results

Superior displacement was 0.3 mm at stage 1, 6.5 mm at stage 2, and 10.7 mm at stage 3. On the cross-body adduction view, there was no distal clavicle overriding at stages 0 and 1, and distal clavicle overriding was observed in five cases (5/6: 83%) at stage 2 and in six cases (6/6: 100%) at stage 3.

Conclusion

We found that AC and trapezoid ligament sectioning induced AC joint instability and that the clavicle could override the acromion on cross-body adduction view regardless of conoid ligament sectioning. The traumatic sections of the AC and trapezoid ligament may lead to high grade AC joint instability, and the distal clavicle may subsequently override the acromion.

Impacted intraarticular fragments of distal radius fractures: A radiographic characterization and analysis of reliability and diagnostic accuracy

BACKGROUND

Reduction using ligamentotaxis may not be effective enough to treat impacted intraarticular fragments of distal radius fractures. Articular incongruence resulting from the loss of reduction is a risk factor for postoperative osteoarthritis and worse clinical outcome. This study aimed to analyze the radiographic characterization of the impacted intraarticular fragments of distal radius fractures using two/three-dimensional computed tomography (CT). Further, we assessed the reliability and diagnostic accuracy in detecting the fragments using plain radiographs.

METHODS

We analyzed 167 three-dimensional CT images of the intraarticular distal radius fractures and selected 12 fractures with impacted intraarticular fragments. We recorded the location, size, and displacement of the fragment using CT images. In addition, six examiners evaluated 25 fractures including those 12 fractures having the fragments using plain radiographs for detecting the fragments and their displacements. Further, we evaluated the reliability and diagnostic accuracy of the plain radiographs in the detection of the fragment.

RESULTS

Fifteen impacted intraarticular fragments were found in 12 wrists. The displacement of the scaphoid facet fragment was significantly larger than that of the lunate facet fragment in CT measurement (7.0 mm and 3.6 mm). Inter and intraobserver reliability of the diagnosis for the fragment in plain radiographs were poor and fair (κ: 0.14 and κ:0.27). Diagnostic accuracy in detecting the fragment in plain radiographs generated mean sensitivity: 0.4, mean specificity: 0.73, and mean accuracy: 0.58. The mean sensitivity in detecting a lunate facet fragment was lower than that of a scaphoid facet fragment in plain radiographs (0.24 and 0.44).

CONCLUSION

Impacted intraarticular fragments were found in 7% of intraarticular distal radius fractures. We observed low reliability and sensitivity in detecting the fragment using plain radiographs. Preoperative recognition of the fragments using plain radiograph were difficult, even though the magnitude of step-off of the scaphoid facet fragment was large.

Partial Trapeziotrapezoid Resection and Thumb Range of Movement After Trapeziometacarpal Joint Fusion-A Biomechanical Study

PURPOSE

Trapeziometacarpal (TMC) joint arthrodesis is an effective treatment for stage III osteoarthritis. Although this procedure alleviates thumb pain and restores grip power and pinch strength, persistent limitation of thumb movement is inevitable. This biomechanical study aimed to investigate the altered kinematics of thumb circumduction motion after TMC joint arthrodesis and subsequent excision of the trapeziotrapezoid (TT) and trapezio-second metacarpal (T-2MC) joint spaces.

METHODS

Eight cadaver upper extremities were mounted on a custom testing apparatus. The hand and carpal bones were fixed to the apparatus, except for the first metacarpal bone, trapezium, and trapezoid. A 50-g load was applied at the tip of the first metacarpal head to generate passive thumb circumduction. An electromagnetic tracking system measured the angular and rotational displacement of the first metacarpal. All specimens were tested in 4 conditions: intact, after simulated TMC joint fusion, after subsequent excision of 3 mm of bone at the TT joint space, and after additional 3 mm resection at the T-2MC joint space.

RESULTS

After simulated TMC arthrodesis, the range of angular motion of thumb circumduction decreased to 25% that of the intact thumb. Subsequent resections at the TT and T-2MC joint spaces increased circumduction ranges to 49% (TT joint) and 73% (TT plus T-2MC joints) that of the intact thumb. The range of thumb rotational motion showed a similar trend.

CONCLUSIONS

Trapeziometacarpal arthrodesis decreased the range of both angular and rotational motion during thumb circumduction. Subsequent resections at the paratrapezial space increased the range of thumb motion, suggesting that hypermobility of the paratrapezial joints increases thumb mobility after TMC joint fusion.

CLINICAL RELEVANCE

Patients with hypermobile paratrapezial joints may have larger thumb movement after TMC joint fusion. Additional resections of the TT and T-2MC joint spaces may further mobilize the thumb in patients who complain of stiffness after TMC fusion.

Arthroscopic Lunate Excision Provides Excellent Outcomes for Low-Demand Patients with Advanced Kienböck's Disease

Purpose

To examine the clinical outcomes of arthroscopic lunate excisions for advanced Kienböck's disease.

Methods

Fifteen patients (six men and nine women; mean age: 65 years; range: 48-83 years) with advanced Kienböck's disease, who underwent arthroscopic lunate resection between April 2008 and March 2016, were reviewed clinically and radiographically after a follow-up of >2 years (mean: 29 months; range: 24-60 months). Clinical parameters, such as wrist range of motion, grip strength, Disabilities of the Arm, Shoulder, and Hand (DASH) score, and patient-rated wrist evaluation (PRWE) score were evaluated. Radiographic parameters included radioscaphoid angle, scaphocapitate angle, carpal height ratio, ulnar-triquetrum distance, and the scaphoid-triquetrum distance. Wilcoxon's signed-rank test was used to compare measurement results.

Results

During the final follow-up, patients exhibited significant improvements, such as 42.9° in wrist range of motion (P = .009), 24.5% of the contralateral side in grip strength (P = .001), 26.2 points in DASH score (P = .002), and 37.8 points in PRWE score (P < .001), compared with the preoperative values. The radioscaphoid and scaphocapitate angles significantly increased by 4.8° (P = .0027) and 3.7° (P = .0012), respectively. The carpal height ratio, ulnar-triquetrum distance, and scaphoid-triquetrum distance significantly decreased by 0.05 (P < .001), 2.6 mm (P < .001), and 1.3 mm (P = .0012), respectively.

Conclusions

Our results suggest that arthroscopic lunate excisions provided excellent postoperative pain relief and functional recovery within 2 years of follow-up. Changes in carpal alignment and stress concentration on the radial side of the carpal bones could occur in the long term; however, arthroscopic lunate excision can be a good surgical option for treating low-demand patients with advanced Kienböck's disease.

Level of Evidence

Level IV, therapeutic case series.

Anatomical Study of Stabilizing Structures of the Extensor Carpi Ulnaris Tendon Around the Wrist

PURPOSE

The sixth dorsal extensor compartment is a relatively common site of stenosing tenosynovitis in the upper extremity, but the exact location of stenosis is not fully understood. The objective of this study was to investigate the detailed anatomy of structures surrounding the extensor carpi ulnaris (ECU) tendon around the wrist.

METHODS

Fifty fresh human cadaveric wrists were used for gross observation and morphology measurements of the sixth dorsal compartment and the ECU subsheath. An additional 13 wrists were used for histological examination. We evaluated the morphology of supporting structures in 3 regions: the ulnar groove (zone I), the ulnar styloid process (zone II), and the triquetrum (zone III).

RESULTS

The fibro-osseous tunnel comprising the ulnar groove and the overlying subsheath (zone I) stabilized the ECU tendon, and the subsheath had thin membranous collagen fibers attached to the periosteum. We consistently found the distal extension of ECU subsheath (zone II), which connected the ulnar styloid process and the dorsal radioulnar ligament. Variations in the length of the distal extension increased with the forearm in pronation. Collagen fiber thickness around the ECU tendon in zone II was greater than that of zone I. In zone III, the overlying extensor retinaculum and septa, which were composed of thick circumferential collagen structures, supported the ECU tendon by attaching to the triquetrum on both sides of the ECU tendon. We found the presence of an ulnar septum of the sixth compartment attached to the triquetrum in 84% of dissected wrists.

CONCLUSIONS

The ECU tendon was supported by the ECU subsheath, which had thin and elastic collagen fibers over the ulnar groove. Distal extension of the subsheath and surrounding radial and ulnar extensor retinaculum septa attached to the triquetrum provided thicker supporting structures.

CLINICAL RELEVANCE

Stenosing ECU tenosynovitis may occur not only in the ulnar groove but also in the more distal ulnar styloid process and triquetrum areas.

Magnetic Resonance Imaging Evaluation of Acute Plastic Deformation of a Pediatric Radius

Acute plastic deformation of long bones is more common in young children. We report a case of an acute plastic deformation of a pediatric radius via magnetic resonance imaging (MRI) evaluation. A 15-year-old boy fell on landing after a jump while practicing soccer, which injured his right forearm. He was diagnosed with a radial neck fracture and a medial epicondylar fracture of the humerus on the basis of plain radiograms. MRI was additionally performed and showed abnormal shadows indicating intramedullary bleeding at multiple bamboo-joint-like deformity sites of the radius. Surgery was performed and injury completely healed. Acute plastic deformation of long bones was often diagnosed by simple radiographic imaging. To our knowledge, there has been no previous reports of plastic deformation evaluated by MRI. If bone plastic deformation is missed, functional impairments such as limited range of motion remain; thus, an early diagnosis of acute bone plastic deformation by performing MRI is recommended.

Treatment of painful median nerve neuroma using pedicled vascularized lateral antebrachial cutaneous nerve with adipofascial flap: a cadaveric study and exploration of clinical application

The most common procedure for the treatment of painful median nerve neuroma is coverage with vascularized soft tissue following external neurolysis. However, the ideal treatment should include reconnecting the proximal and distal stumps of the damaged nerve to allow the growth of regenerating axons to their proper targets for a functional recovery. We developed a useful technique employing radial artery perforator adipofascial flap including the lateral antebrachial cutaneous nerve (LABCN) to repair the median nerve by vascularized nerve grafting and to achieve coverage of the nerve with vascularized soft tissue. In an anatomical study of 10 fresh-frozen cadaver upper extremities, LABCN was constantly bifurcated into two branches at the proximal forearm (mean: 8.2 cm distal to the elbow) and two branches that run in a parallel manner toward the wrist. The mean length of the LABCN branches between the bifurcating point and the wrist was 18.2 cm, which enabled inclusion of adequate length of the LABCN branches into the radial artery perforator adipofascial flap. The diameters of the LABCN branches (mean: 1.7 mm) were considered suitable to bridge the funiculus of the median nerve defect after microsurgical internal neurolysis. In all cadaver upper extremities, the 3-cm median nerve defect at the wrist level could be repaired using the LABCN branches and covered with the radial artery perforator adipofascial flap. On the basis of this anatomical study, the median nerve neuroma was successfully treated with radial artery perforator adipofascial flap including vascularized LABCN branches.

The Role of the Acromioclavicular Ligament in Acromioclavicular Joint Stability: A Cadaveric Biomechanical Study

Background:

Acromioclavicular (AC) joint dislocation is evaluated using the radiologically based Rockwood classification. The relationship between ligamentous injury and radiological assessment is still controversial.

Purpose/Hypothesis:

To investigate how the AC ligament and trapezoid ligament biomechanically contribute to the stability of the AC joint using cadaveric specimens. The hypothesis was that isolated sectioning of the AC ligament would result in increased instability in the superior direction and that displacement >50% of the AC joint would occur.

Study Design:

Controlled laboratory study.

Methods:

Six shoulders from 6 fresh-frozen cadavers were used in this study. Both the scapula and sternum were solidly fixed on a customized wooden jig with an external fixator. We simulated distal clavicular dislocation with sequential sectioning of the AC and coracoclavicular (CC) ligaments. Sectioning stages were defined as follows: stage 0, the AC ligament, CC ligament, and AC joint capsule were left intact; stage 1, the anteroinferior bundle of the AC ligament, joint capsule, and disk were sectioned; stage 2, the superoposterior bundle of the AC ligament was sectioned; and stage 3, the trapezoid ligament was sectioned. The distal clavicle was loaded with 70 N in the superior and posterior directions, and the magnitudes of displacement were measured.

Results:

The amounts of superior displacement averaged 3.7 mm (stage 0), 3.8 mm (stage 1), 8.3 mm (stage 2), and 9.5 mm (stage 3). Superior displacement >50% of the AC joint was observed in stage 2 (4/6; 67%) and stage 3 (6/6; 100%). The magnitudes of posterior displacement were 3.7 mm (stage 0), 3.7 mm (stage 1), 5.6 mm (stage 2), and 9.8 mm (stage 3). Posterior displacement >50% of the AC joint was observed in stage 3 (1/6; 17%).

Conclusion:

We found that the AC ligaments contribute significantly to AC joint stability, and superior displacement >50% of the AC joint can occur with AC ligament tears alone.

Clinical Relevance:

The AC ligament plays an important role not only in horizontal stability but also in vertical stability of the AC joint.

Biomechanical Effects of Radioscapholunate Fusion With Distal Scaphoidectomy and Triquetrum Excision on Dart-Throwing and Wrist Circumduction Motions

PURPOSE

Distal scaphoid and triquetrum excisions can improve the range of wrist motion after radioscapholunate (RSL) fusion, but little is known about the kinematics of dart-throwing and global circumduction motions. We hypothesized that these excisions could increase the range of motion without causing midcarpal instability.

METHODS

Seven fresh-frozen cadaver upper extremities were mounted on a testing apparatus after isolation and preloading of the tendons of the flexor carpi radialis, flexor carpi ulnaris, extensor carpi radialis, and extensor carpi ulnaris. Sequential loadings of the flexor carpi ulnaris and extensor carpi radialis simulated active dart-throwing motion. Passive circumferential loading produced the wrist circumduction motion. We measured the range of wrist motions with an electromagnetic tracking system in 4 experiments: intact, simulated RSL fusion, RSL fusion with distal scaphoid excision, and RSL fusion with distal scaphoid and total triquetrum excisions. To evaluate midcarpal stability, we conducted passive mobility testing of the distal carpal row in the radial, volar, ulnar, and dorsal directions.

RESULTS

Radioscapholunate fusion decreased the dart-throwing motion to a mean of 46% of the baseline value; distal scaphoid and triquetrum excisions increased the mean arc to 50% and 62%, respectively. Radioscapholunate fusion diminished the wrist circumduction to a mean of 43% of the baseline value, which increased to a mean of 58% and 74% after distal scaphoid and triquetrum excision, respectively. A significant increase in radial deviation was noted after distal scaphoid excision, and subsequent triquetrum excision significantly increased motion in the ulnar-palmar direction. Regarding midcarpal stability, dorsal translation significantly increased after distal scaphoid and triquetrum excisions.

CONCLUSIONS

Distal scaphoid and triquetrum excision after RSL fusion improved both dart-throwing and circumduction motions, but dorsal midcarpal instability occurred.

CLINICAL RELEVANCE

Subsequent carpal excisions may improve short-term outcome by increasing motions in a RSL-fused wrist; however, a potential risk of midcarpal instability should be considered.

Safe zone of pin insertion for nonbridging external fixators in distal radial fractures: MRI analysis

BACKGROUND

Of the anatomical reduction and fixation methods used to treat distal radius fracture, non-bridging external fixation has the advantage of enabling early wrist motion. The surgical technique relies on successful placement of the pin in individual fracture fragments. The present study aimed to identify the safe zone of pin insertion for a non-bridging external fixator into the distal radius that avoids metal impingement of extensor tendons.

METHODS

The width and length of the septal attachments of the extensor retinaculum were measured on axial MR images of 62 wrists.

RESULTS

The 2-3 septum was the widest and longest, with a width of 2-7 mm and a location 0-36 mm proximal to the wrist joint. The width of the 1-2 septum was 2-6 mm, and was widest at 10 mm proximal to the joint. The 1-2 septum was triangular-shaped, while the 2-3 septum was oval-shaped. The 3-4 and 4-5 septa had narrow attachments and were adequate for pin insertion (with a pin 1-2 mm in width) at a position less than 8 mm proximal to the wrist. The width of the 1 R septum (radial to the 1st septum) was 2-6 mm at the radiovolar aspect of the wrist.

CONCLUSIONS

There were two safe pin insertion sites; the first was safe at the distal aspect only (8-10 mm proximal to the wrist) and included the 1-2, 3-4, and 4-5 septa, while the second was safe from 0 mm to 32-38 mm proximal to the wrist and included the 1 R and the 2-3 septa. The 1 R septum had adequate size for use as a new pin insertion site that aligns in the internervous plane and has minimal risk of superficial radial nerve injury.

Biomechanical analysis of simultaneous distal and proximal radio-ulnar joint instability

BACKGROUND

Simultaneous dislocation of the proximal and distal radio-ulnar joints without bony injuries has been reported, but the mechanism remains unclear. We investigated concurrent proximal and distal radio-ulnar joint instability after sequential sectioning of the annular ligament, triangular fibrocartilage complex, and quadrate ligament.

METHODS

We performed this biomechanical study with six fresh-frozen cadaveric upper extremities. Proximal and distal radio-ulnar joint displacement was measured using an electromagnetic tracking device during passive mobility testing with anterior, lateral, and posterior loads on the radial head with pronation, supination, and neutral rotation. Measurements were statistically analyzed using the generalized linear mixed model.

FINDINGS

Proximal radio-ulnar joint instability was significantly greater after sectioning of the annular (lateral: 1.4%, P < .05; posterior: 0.7%, P < .05) and quadrate (lateral: 43.7%, P < .05; posterior: 29.5%, P < .05) ligament. Distal radio-ulnar joint instability was significantly greater in every sequential stage (final stage: anterior: 24.1%, P < .05; lateral 21.0%, P < .05; posterior: 31.3%, P < .05). Finally, significant simultaneous instability of the joints was observed after sectioning of the annular ligament, triangular fibrocartilage complex, and quadrate ligament, and neutral rotation potentially induced gross instability.

INTERPRETATION

Our ligament injury model induced simultaneous proximal and distal radio-ulnar joint instability without bony or interosseous membrane injury, probably induced by severe soft tissue injury. Proximal radio-ulnar joint instability may influence distal radio-ulnar joint instability from pivoting of the interosseous membrane. Our findings will help surgeons evaluate the magnitude of soft tissue injury and plan surgery for patients with simultaneous proximal and distal radio-ulnar joint instability.

Clinical outcomes of unstable metacarpal and phalangeal fractures treated with a locking plate system: a prospective study

We prospectively assessed clinical and radiological outcomes of locking plate fixation in treating unstable fractures in 11 metacarpals, 15 proximal phalanges, and eight middle phalanges in 34 consecutive patients from October 2011 to December 2016. Median length of follow-up was 14 months (range 12-24). The motion of finger joints, bony union, and complication rates were recorded. The median postoperative range of motion of the two interphalangeal joints and the metacarpophalangeal joint was 82% of the contralateral hands. Fractures in the three locations had significantly different recovery of the finger motion, with the best recovery for the metacarpal fractures. Closer distance between the plate edge and joint line was associated with a more limited range of the finger motion. The clinical outcomes approached an acceptable level at final follow-up. Finger stiffness is unavoidable after locking plate fixation of metacarpal and phalangeal fractures even with early hand therapy, with stiffness occurring in 10 out of 34 cases at the time of final follow-up 1 year after surgery. Level of evidence: II.

Robust method to create a standardized and reproducible atrophic non-union model in a rat femur

Objective

No evidence exists about which biological approach is more reliable for creating non-union model. We investigated how to create a reproducible atrophic non-union model in a rat femur.

Methods

We compared three groups: simple osteotomy (group A), partial periosteum cauterization (group B), and extensive periosteum and bone marrow resection (group C).

Results

All samples in group C demonstrated atrophic non-union in radiological, histological, and biomechanical analyses, however half of the samples in group B showed fracture healing at week 16.

Conclusion

Extensive resection of periosteum and bone marrow is important for a reproducible atrophic non-union model in a rat femur.

Dorsal Intercarpal Ligament Preserving Arthrotomy and Capsulodesis for Scapholunate Dissociation

Carpal instability secondary to scapholunate (SL) ligament tears can lead to a significant disability of the wrist. Different surgical procedures have been proposed to treat SL instability. A variety of dorsal capsulodesis techniques tethering the scaphoid have been used in patients with SL dissociation. We report a novel technique of modified dorsal intercarpal ligament (DICL) capsulodesis for the treatment of SL dissociation. The surgical indication for this procedure is complete SL ligament tear with a reducible carpal malalignment and no secondary osteoarthritis. This procedure is indicated when the remnant of torn ligament in the dorsal SL interosseous space is available for repair. First, carpal malalignment is corrected and the scaphoid and the lunate are temporarily fixed with a transosseous screw or Kirschner wires. Using a dorsal approach, the DICL is then exposed, which originates from the triquetrum and attaches to the scaphoid, trapezium, and trapezoid. The distal and proximal borders of the ligament are identified and elevated without detaching the attachment sites. The DICL is transferred proximally to reinforce the dorsal SL interosseous ligament. The wrist joint is immobilized for 3 weeks postoperatively, and dart-throwing motion is permitted until temporary SL fixation is removed at 2 to 3 months after surgery. A wrist brace is recommended until 3 to 6 months after the first surgery depending on the patient's occupation and sports activity.

Vascularized pedicled bone graft from the distal radius supplied by the anterior interosseous artery for treatment of ulnar shaft nonunion: An anatomical study of cadavers and a case report

BACKGROUND

A vascularized distal radius graft can be a reliable solution for the treatment of refractory ulnar nonunion. The aim of this study is to establish the anatomical basis of a vascularized bone graft pedicled by the anterior interosseous artery and report its clinical application, using cadaveric studies and a case report.

METHODS

Fourteen fresh frozen cadaveric upper limbs were used. The branches of the anterior interosseous artery (the 2, 3 intercompartmental supraretinacular artery and the fourth extensor compartment artery) were measured at the bifurcation site. The anatomical relationship between the anterior interosseous artery and motor branches of the posterior interosseous nerve was investigated. An anterior interosseous artery pedicled bone flap was used in a 48-year-old woman with refractory ulnar nonunion.

RESULTS

There were two variations depending on whether the 2,3 intercompartmental supraretinacular artery branched off distally or proximally from the terminal motor branch of the posterior interosseous nerve. The proximal border of the graft was located at an average of 10.5 cm (range, 6.5-12.5 cm) from the distal end of the ulnar head in the distal type (57%) and 17.5 cm (range, 9.5-21.5 cm) in the proximal type (43%). In the clinical application, successfully consolidation was achieved 4 months post-surgery. The patient had not developed any postoperative complications until the 2-year postoperative follow-up.

CONCLUSIONS

The anterior interosseous artery-pedicled, vascularized distal radius bone graft would be a reliable alternative solution for the treatment of an ulnar nonunion located within the distal one-third of the ulna.

Vascularized medial femoral condyle graft for nonunion after failed radiolunate arthrodesis

Since the medial femoral condyle flap was originally described in 1989, the indications for use of this versatile flap as a graft have broadened. We used this procedure in a patient with nonunion after failed arthrodesis of the radiolunate joint. Early bone union was achieved, with marked postoperative improvement in VAS and DASH scores.

Effect of soft tissue injury and ulnar angulation on radial head instability in a Bado type I Monteggia fracture model

The effects of soft tissue damage and ulnar angulation deformity on radial head instability in Monteggia fractures are unclear. We tested the hypothesis that radial head instability correlates with the magnitude of ulnar angular deformity and the degree of proximal forearm soft tissue injury in Bado type I Monteggia fractures.We performed a biomechanical study in 6 fresh-frozen cadaveric upper extremities. Monteggia fractures were simulated by anterior ulnar angulation osteotomy and sequential sectioning of ligamentous structures. We measured radial head displacement during passive mobility testing in pronation, supination, and neutral rotation using an electromagnetic tracking device. Measurements at various ligament sectioning stages and ulnar angulation substages were statistically compared with those in the intact elbow.Radial head displacement increased with sequential ligament sectioning and increased proportionally with the degree of anterior ulnar angulation. Annular ligament sectioning resulted in a significant increase in displacement only in pronation (P < .05). When the anterior ulnar deformity was reproduced, the radial head displaced least in supination. The addition of proximal interosseous membrane sectioning significantly increased the radial head displacement in supination (P < .05), regardless of the degree of anterior ulnar angulation.Our Monteggia fracture model showed that radial head instability is influenced by the degree of soft tissue damage and ulnar angulation. Annular ligament injury combined with a minimal (5°) ulnar deformity may cause elbow instability, especially in pronation. The proximal interosseous membrane contributes to radial head stability in supination, regardless of ulnar angulation, and proximal interosseous membrane injury led to significant radial head instability in supination.

Tamai Zone 1 Fingertip Amputation: Reconstruction Using a Digital Artery Flap Compared With Microsurgical Replantation

PURPOSE

The surgical treatment of fingertip amputations is controversial. This study was designed to compare the clinical results of 2 surgical procedures for fingertip amputation: reconstruction with a digital artery flap and microsurgical replantation.

METHODS

Between 2003 and 2015, 37 patients with Tamai zone 1 fingertip amputation of the index or middle finger were treated by reconstruction with a digital artery flap (n = 23) or microsurgical replantation (n = 14). Data for these patients were evaluated retrospectively. Nerve suture was not conducted in microsurgical replantation because spontaneous sensory recovery is expected in zone 1 replantation. Primary outcomes included hand dexterity (Purdue Pegboard Test), and disability of the upper extremity (Disabilities of the Arm, Shoulder, and Hand score). Secondary outcomes included strength (key pinch), digital sensitivity (Semmes-Weinstein test), and finger mobility (% total active motion).

RESULTS

The average follow-up period was 34 months. There was no significant difference in the primary outcomes between the 2 groups. The reconstruction group showed significantly better results for the secondary outcomes.

CONCLUSIONS

This study suggests that the 2 procedures were comparable regarding postoperative activities of daily living and hand performance, but reconstruction using a digital artery flap gave better objective functional outcomes than microsurgical replantation.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Comparison of Five Years Clinical and Radiological Outcomes between Progressive and Non-Progressive Wrist Osteoarthritis after Volar Locking Plate Fixation of Distal Radius Fractures

BACKGROUND

This study aimed to identify the effect of the progression of postoperative wrist osteoarthritis on 5 years clinical and radiological outcomes after volar locking plate fixation of distal radius fractures.

METHODS

Altogether, 56 patients with distal radius fractures were followed up 5 years after surgery. Clinical assessment was performed using the Mayo modified wrist score, a visual analogue scale of pain, the Japanese version of the Disabilities of the Arm, Shoulder, and Hand score, and Patient-related wrist evaluation. Standardized wrist radiographs were used to assess wrist morphology and the Knirk and Jupiter's degree of osteoarthritis. Multivariate logistic regression was used to analyze postoperative morphological changes in the wrist and carpal alignment regarding their correlation with progression of wrist osteoarthritis.

RESULTS

Progression of postoperative wrist osteoarthritis was recognized in 37 of the 56 cases (66.1%). Compared with the clinical outcomes at the time of the fracture union completion, almost clinical outcomes improved up to 5 years follow-up time as well as at 1 year after surgery. The range of wrist flexion at 5 years follow-up was significantly less in the progressive osteoarthritis group than in those with non-progressive osteoarthritis. The persistent step-off immediately after surgery significantly affected the postoperative progression of wrist osteoarthritis. Changes in the radial inclination, volar tilt, and radioscaphoid angle correlated with progression of wrist osteoarthritis. The highest correlation was with the change of radioscaphoid angle.

CONCLUSIONS

Good clinical results were maintained at 5 years after surgery, but progression of postoperative wrist osteoarthritis interfered with improvement of wrist flexion. Change in the radioscaphoid angle was the factor that was most highly correlated with progression of postoperative wrist osteoarthritis.

Arthroscopic Distal Scaphoid Resection for Isolated Scaphotrapeziotrapezoid Osteoarthritis

PURPOSE

To investigate the radiographic and clinical results of arthroscopic distal scaphoid resection for isolated scaphotrapeziotrapezoid (STT) osteoarthritis and analyze the radiographic parameters associated with the functional outcomes.

METHODS

From 2008 to 2014, 17 wrists with symptomatic isolated STT osteoarthritis without carpal deformity underwent arthroscopic distal scaphoid resection. We evaluated visual analog scale (VAS) scores for pain, grip strength, pinch strength, and Patient-Rated Wrist Evaluation (PRWE) scores before surgery and at the final follow-up. We analyzed correlations between the resection height and the radiographic and functional outcomes.

RESULTS

The average follow-up period was 42 months. The average VAS score improved from 6.1 ± 2.3 before surgery to 1.7 ± 1.9 after surgery. The average grip strength improved from 18 ± 6 to 19 ± 9 kg, pinch strength from 2.5 ± 1.1 to 4.4 ± 1.7 kg, and PRWE score from 52 ± 23 to 32 ± 24. Carpal deformity (C-L angle of > 15°) was seen in 2 patients at the final follow-up. The deformity was more likely to occur when the resection height was greater than 3 mm.

CONCLUSIONS

Arthroscopic distal scaphoid resection alone can reduce pain and improve functional outcomes for early to mid-stage isolated STT osteoarthritis in patients without dorsal intercalated segment instability deformity. Resection of greater than 3 mm of the distal scaphoid may result in carpal malalignment.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Three-Dimensional Kinematic Analysis of the Distal Radioulnar Joint in the Axial-Loaded Extended Wrist Position

PURPOSE

To assess the wrist joints of healthy volunteers in extended and loaded states versus the unloaded state by using computed tomography (CT) to analyze the in vivo 3-dimensional movements in the distal radioulnar joint (DRUJ).

METHODS

The dominant arms of 9 volunteers with healthy wrists were studied. We mounted a compression device onto the elbows in an inverted position. A 0-kg and 7-kg load each was applied during low-dose radiation CT imaging and a bone model was produced. We marked the insertion sites for the 4 radioulnar ligaments stabilizing the DRUJ: palmar superficial radioulnar ligament (PS-RUL), dorsal superficial radioulnar ligament (DS-RUL), dorsal deep radioulnar ligament (DD-RUL), and palmar deep radioulnar ligament (PD-RUL). Using Marai's method, each ligament was virtualized and the length of each simulated ligament was measured. We also computed the 3-dimensional displacement and corresponding rotation of the distal ulna where it comes into contact with the radius in the sigmoid notch.

RESULTS

The lengths of palmar ligaments (PS-RUL and PD-RUL) increased significantly under loaded conditions, and although not significant, the length of dorsal ligaments (DS-RUL and DD-RUL) tended to increase. When the wrist was loaded, the ulna rotated toward the open palmar side.

CONCLUSIONS

The length of simulated radioulnar ligaments increased when the wrist joint was loaded in an extended position. This kinematic movement of DRUJ separation under a loading condition is different from physiological active movement.

CLINICAL RELEVANCE

The 3-dimensional kinematic analysis revealed that palmar radioulnar ligaments were stretched during axial loading, suggesting that a tear of the palmer ligament can result from a fall on an outstretched hand.

Scaphoid Motion of the Wrist with Scapho-trapezio-trapezoidal Osteoarthritis-A Pilot Study

BACKGROUND

The purpose of this study was to investigate scaphoid motion within the scapho-trapezio-trapezoidal (STT) joint during wrist motion in the presence of STT joint osteoarthritis (OA).

METHODS

We studied 11 wrists with STT OA and 5 normal wrists. Computed tomography (CT) images were acquired in five wrist positions (maximum active flexion, extension, radial deviation, ulnar deviation, and neutral position). The 3-dimensional surface models of the radius and scaphoid were constructed and the motion of scaphoid relative to the radius was calculated.

RESULTS AND CONCLUSIONS

During wrist flexion/extension motion, the scaphoid rotated mostly in the flexion/extension plane. The angle tended to be smaller in STT OA than in normal. During wrist radioulnar deviation, the scaphoid was in an extended position in neutral wrist in STT OA. The motion of scaphoid in STT OA was divided into two types: a rigid type and mobile type. The mobile type rotated closer to the flexion/extension plane than the rigid type. Taking into account scaphoid motion during wrist movement before surgery may provide better results in the treatment of STT OA.

Quality of life in patients with toe-to-hand transplantation

OBJECTIVE

Toe-to-hand transplantation is a reliable procedure that replaces like-with-like in cases of a lost thumb or finger. The aim of this study is to investigate the effects of toe transplantation on patients from the perspectives of quality of life (QOL) and disability.

METHODS

Ten patients with traumatic amputation of a digit underwent reconstruction with toe transplantation. The mean age at injury was 40.2 years (range 17-59 years). Reconstructive options were 5 wrap-around flaps to 2 thumbs and 3 index fingers; 2 second-toe transplantations to 2 middle fingers, and 3 hemipulp-free flaps from the great toe to a thumb and an index finger. We hypothesized that toe transplantation would improve postoperative QOL and disability. Outcome assessments included completion of the SF-36, SAFE-Q, and DASH questionnaires before and after reconstruction. Scores on each test were calculated and intra-individual comparisons were made.

RESULTS

All scores for the eight SF-36 health domains improved, with a significant difference in Vitality from before to after surgery. In contrast, scores for all five SAFE-Q items worsened, with significant changes for the 'Pain and Pain-Related' and 'Physical Functioning and Daily Living' subscales. DASH scores improved after surgery in all cases.

CONCLUSIONS

Our results suggest that toe-to-hand transplantation for amputated finger reconstruction is a good option in terms of improved QOL. However, worsened SAFE-Q scores imply that donor site problems could be expected and must be taken into account during surgical planning.

Magnetic resonance imaging analysis of the extensor carpi ulnaris tendon and distal radioulnar joint in triangular fibrocartilage complex tears

BACKGROUND

We compared the incidence of extensor carpi ulnaris (ECU) tendon and distal radioulnar joint (DRUJ) abnormalities using magnetic resonance imaging (MRI) between patients with triangular fibrocartilage complex (TFCC) tears and subjects without ulnar wrist pain. Additionally, we aimed to identify potential predictors of these MRI lesions.

METHODS

The TFCC group comprised 70 consecutive patients with TFCC tears. The control group comprised 70 age- and sex-matched subjects without ulnar wrist pain. We evaluated the presence or absence of fluid collection in the DRUJ and ECU peritendinous area and longitudinal ECU tendon splitting. Dimensions of the fluid collection area around the ECU tendon were measured to evaluate the severity. The incidences of these abnormal MRI findings were compared between the two groups. We analyzed the correlation between the presence of ECU tendon and DRUJ lesions and variables including age, magnitude of ulnar variance, and type of TFCC tear.

RESULTS

Significant differences were found between the two groups in the incidence of fluid collection of the DRUJ and ECU peritendinous area, and longitudinal ECU tendon splitting. Among the 70 patients with TFCC tears, age and the magnitude of ulnar variance were significantly correlated with the severity of fluid collection around the ECU tendon. The magnitude of ulnar variance in patients with DRUJ fluid collection was significantly larger than that in patients without fluid collection. There was a significant correlation between the presence of disc tears and DRUJ fluid collection.

CONCLUSION

We found a higher incidence of accompanying abnormal MRI findings of the ECU tendon and DRUJ in patients with TFCC tears than in the control group. The presence of disc tears, the magnitude of ulnar variance, and age may be risk factors for these MRI lesions associated with TFCC tears.

A Rare Case of Pre-Existing Deep Venous Thrombosis in the Peroneal Vein of a Free Osteocutaneous Fibula Flap

Background  Deep venous thrombosis (DVT) of the lower leg is a widespread medical problem and is associated with hypercoagulable states. Although spontaneous thrombosis of the peroneal vein of a fibula flap is theoretically possible, few cases of asymptomatic DVT of the peroneal vein encountered during fibula flap harvest have been reported.

Case Report  A 45-year-old man presented with segmental bone defects of the tibia resulting from a fall. Treatment with a free vascularized osteocutaneous fibula flap from the contralateral lower leg was scheduled. Intraoperatively, diffuse thrombi were found in the peroneal venous system. After removal of thrombi, the fibula was grafted with anastomosis of the peroneal vessels to the recipient posterior tibial vessels. The skin paddle of the flap became congested after surgery; exsanguination of the skin paddle was performed with multiple skin incisions to relieve congestion. Despite treatment, the skin paddle became partially necrotic and additional skin grafting was performed. Bone union of the grafted fibula was achieved 5 months after initial surgery.

Conclusions  To the best of our knowledge, only six cases of pre-existing DVT in the peroneal vein of a free osteocutaneous fibula flap have been reported. In three of these cases, the fibula flap was successfully grafted. Although successful free osteocutaneous fibula flap surgery might be possible in patients with peroneal venous thrombosis, careful preoperative evaluation is recommended for high-risk patients.

Reconstruction of a metacarpal head defect due to bite injury: two case reports

We present two rare cases of acute osteomyelitis after bite injury that were reconstructed with a third metacarpal base osteoarticular flap and a vascularised medial femoral trochlea osteocartilaginous flap. The outcomes show that a vascularised osteoarticular flap is a good treatment option for a metacarpal head defect.

Predictors of Hand Dexterity after Single-Digit Replantation

Background Microsurgical replantation of the thumb and digits has become an increasingly familiar technique in clinical practice worldwide. However, successful digit replantation does not always provide better hand function than revision amputation. Little information is available regarding predictors of motor skill activities of replanted hands. Therefore, we retrospectively evaluated hand dexterity after single-digit replantation at a minimum follow-up of 1 year and analyzed the factors influencing dexterity.

Methods This retrospective cohort study included 23 patients treated for amputation injuries at our institution from 2014 to 2015. Patients with amputations from Tamai's zone 2 to 5 of the thumb (3 patients), index finger (11 patients), or middle finger (9 patients) who underwent digital replantation surgery and were followed up for more than 1 year were included. Follow-up evaluations were conducted at an average of 23 months postoperatively (range: 13–25 months). We hypothesized that possible factors influencing hand dexterity after single-digit replantation were patient age, injured finger, key pinch strength, Semmes–Weinstein test result, and percentage of total active motion. Relationships between the outcome variable, which was the result of the Purdue Pegboard Test of hand dexterity, and explanatory variables were analyzed using Spearman's correlation coefficient. A p-value of < 0.05 indicated statistical significance.

Results No postoperative complications occurred. Univariate analysis indicated that decreased hand dexterity after single-digit replantation was significantly associated with older age (p = 0.001) and poor recovery of sensation, as shown by the Semmes–Weinstein test (p = 0.012).

Conclusion Patient age was a risk factor for low hand dexterity after replantation surgery. Recovery of finger sensitivity enhanced dexterity of motor skill activities following finger replantation surgery.

Vascularized bone graft from the second metacarpal base for trapeziometacarpal joint arthrodesis

Three female patients underwent TMC joint arthrodesis using a vascularized bone graft from the second metacarpal base. Surgical indications were nonunion after failed TMC joint arthrodesis and osteoarthritis and severe osteoporosis. All cases achieved early bone union, and marked postoperative improvement in the VAS and DASH scores.

Osteogenic extracellular matrix sheet for bone tissue regeneration

The application of extracellular matrix (ECM) sheets without a scaffold is not extensively reported in bone regenerative medicine. The aim of the present study was to demonstrate that an osteogenic ECM sheet (OECMS) can retain ECM integrity and growth factors to enhance bone formation in a rat non-union model. OECMS was produced from osteogenic cell sheets (OCS). Collagen and growth factor [bone morphogenetic protein 2 (BMP-2), vascular endothelial growth factors (VFGFs), basic fibroblast growth factor (bFGF) and transforming growth factor β1 (TGF-β1)] concentrations in the OECMS were quantified by enzyme-linked immunosorbent assay (ELISA). Next, hydroxyapatite (HA) constructs combined with OECMSs were implanted subcutaneously into the rats' backs to evaluate their osteoinductive capacity by histological evaluation. In addition, OECMSs were implanted in a rat femoral non-union model. 18 male Fischer 344 inbred rats were divided into OECMS and control groups. Fracture healing was evaluated by radiological and histological analyses at 2, 5 and 8 weeks and biological analysis at 8 weeks. Collagen I and growth factors were retained in the OECMSs. Osteoid formation was identified in the HA combined with OECMS at 4 weeks. Enhanced bone regeneration at the non-union of the OECMS group was confirmed at 5 and 8 weeks. Biomechanical testing revealed a significantly higher maximum bending load in the OECMS group as compared to the control group at 8 weeks. The results demonstrated that OECMS retained BMP-2 and TGF-β1 and high osteoinductive and osteoconductive capacity. As such, OECMS represents a potential new scaffold-free material for bone tissue engineering.

Osteogenesis of osteogenic matrix cell sheets preserved in culture medium in a rat model

Osteogenic matrix cell sheets (OMCSs) are ideal for bone regeneration. Transportation of OMCSs may be necessary, during which their osteogenic ability must be maintained. Here, we evaluated different media and temperatures for OMCS preservation. Bone marrow stromal/stem cells (BMSCs) were obtained from Fischer rats and analyzed for stem cell markers by flow cytometry. OMCSs were prepared from BMSCs by treatment with dexamethasone and ascorbic acid phosphate. After OMCS collection, they were stored in minimum essential medium (MEM) or Hank’s balanced salt solution (HBSS) at 37, 22, or 4°C for 24 hours. Cell viability and cytotoxic effects in the preservation conditions were determined by adenosine triphosphate (ATP) contents and lactate dehydrogenase (LDH) release, respectively. Osteogenesis was assessed by subcutaneously implanting preserved OMCSs around β-tricalcium phosphate ceramic disks into syngeneic rats. Implants were evaluated by alkaline phosphatase (ALP) activities, osteocalcin contents, and histology. Mesenchymal stem cells comprised 51% of primary cultured BMSCs. ATP contents were significantly different in OMCSs stored in MEM or HBSS at 22°C and 4°C. LDH release was significantly different in OMCSs stored in HBSS at 22°C and 4°C. The highest LDH release was observed in OMCSs stored in HBSS at 37°C. ALP activities and osteocalcin contents were the lowest in implanted OMCSs stored in HBSS at 37°C at four weeks after subcutaneous implantation. There was a significant difference in the osteocalcin levels of implanted OMCSs stored in MEM at 37°C and HBSS at 4°C. Abundant bone tissue around and inside disks was found in histological sections of OMCSs stored in all preservation conditions except for MEM and HBSS at 37°C. Maintaining the osteogenic ability of OMCSs during transport is important, and preservation of OMCSs in MEM or HBSS at 4°C or 22°C is a simple and inexpensive method.

Malignant Mixed Tumor of the Finger: A Case Report

We present a very rare case of malignant chondroid syringoma of the fingertip in a 44-year-old man that was reconstruced by neurovascular island flap after the complete tumor resection of the fingertip. Although it is a rare tumor at an unusual area, it should be included in the differential diagnosis of the finger tumors.

Temperature Effect on Bilirubin Adsorption with the Anion Exchange Resin BR-601

Plasma perfusion with the anion exchange resin BR-601 is an effective method to treat patients with hepatic failure and hyperbilirubinemia. To assess the temperature dependency of bilirubin sorption in vitro, isotherm studies with human pathologic plasmas and an albumin-bilirubin solution were carried out. Results showed that BR-601 was more effective at 37°C and 42°C than at 4°C and 25°C for sorbing bilirubin. Therefore, plasma sorption at near physiologic temperature would be expected to be more efficient for plasma treatment than sorption at ambient temperature.

Effect of Anticoagulant on Biocompatibility in Membrane Plasmapheresis

The effect of heparin or citrate anticoagulation on blood cellular, complement pathway and coagulation pathway was investigated in a membrane plasma exchange procedure. Two membrane plasma separators constructed of cellulose di-acetate (CA) and polyvinyl chloride (PVC) were evaluated with heparin or citrate alone for anticoagulation in a 26 year old male with myasthenia gravis. Maximum white blood cell counts decrease was 21% at 30 min for the CA with heparin while no decrease was observed for the other schemes. Platelet counts changes were comparable between heparin and citrate, while the PVC groups showed less changes than the CA groups. The CA groups, regardless of the type of anticoagulant used, indicated that complement activation occurred via the classical pathway within the module in addition to the activation via alternative pathway for the CA with heparin. In the PVC groups, complement activation was noted to occur only when heparin was used for anticoagulation. PT and PTT showed slight increases with citrate, while they were remarkably prolonged with heparin. Citrate showed less changes in cellular and humoral factors compared to heparin. CA with heparin was the most activating combination of membrane material and anticoagulant, while the PVC with citrate was the least activating combination.

Biomechanical study of isolated radial head dislocation

Background

Isolated radial head dislocation is a rare injury with an unclear pathomechanism, and the treatment is controversial. The purpose of the present study was to investigate the biomechanical contributions of the annular ligament, quadrate ligament, interosseous membrane, and annular ligament reconstructions to proximal radioulnar joint stability.

Methods

Five fresh frozen cadaveric upper extremities were amputated above the elbow and solidly fixed on a customized jig. Radial head dislocation was reproduced by sequential sectioning of ligamentous structures and passive mobility testing. Radial head displacement during mobility testing was measured with an electromagnetic tracking device in three forearm rotation positions. The data were compared among different sectioning stages and between two types of simulated ligamentous reconstruction.

Results

Lateral displacement of the radial head significantly increased in the neutral forearm rotation after annular ligament sectioning (46 ± 10%, p < 0.05). After quadrate ligament sectioning, we found significant posterior (67 ± 36%, p < 0.05) and lateral (74 ± 24%, p < 0.01) displacement in neutral forearm rotation and pronation. Significant radial head displacement was found in all directions and in all forearm positions after sequential sectioning of the proximal half of the interosseous membrane. Anatomical annular ligament reconstruction stabilized the proximal radioulnar joint except for anterior laxity in neutral forearm rotation (15 ± 6%, p < 0.05). The radial head with Bell Tawse procedure was significantly displaced in all directions.

Conclusion

The direction of radial head instability varied depending on the degree of soft tissue sectioning and specific forearm rotation. Anterior radial head dislocation may involve more severe ligament damage than other types of dislocation. Anatomical annular ligament reconstruction provided multidirectional radial head stability.

Bone regeneration with osteogenic matrix cell sheet and tricalcium phosphate: An experimental study in sheep

AIM

To determine the effects of a cell sheet created from sheep bone marrow and tricalcium phosphate (TCP) on osteogenesis.

METHODS

Bone marrow cells were harvested from a sheep and cultured in a minimal essential medium (MEM) containing ascorbic acid phosphate (AscP) and dexamethasone (Dex). After 2 wk, the formed osteogenic matrix cell sheet was lifted from the culture dish using a scraper. Additionally, harvested bone marrow cells were cultured in MEM only as a negative control group, and in MEM with AscP, Dex, and β-glycerophosphate as a positive control group. For in vitro evaluation, we measured the alkaline phosphatase (ALP) activity and osteocalcin (OC) content in the media of the cultured cells from each group. For in vivo analysis, a porous TCP ceramic was used as a scaffold. We prepared an experimental group comprising TCP scaffolds wrapped with the osteogenic matrix cell sheets and a control group consisting of the TCP scaffold only. The constructs were implanted subcutaneously into athymic rats and the cell donor sheep, and bone formation was confirmed by histology after 4 wk.

RESULTS

In the in vitro part, the mean ALP activity was 0.39 ± 0.03 mg/well in the negative control group, 0.67 ± 0.04 mg/well in the sheet group, and 0.65 ± 0.07 mg/well in the positive control group. The mean OC levels were 1.46 ± 0.33 ng/well in the negative control group, 3.92 ± 0.16 ng/well in the sheet group, and 4.4 ± 0.47 ng/well in the positive control group, respectively. The ALP activity and OC levels were significantly higher in the cell sheet and positive control groups than in the negative control group (P < 0.05). There was no significant difference in ALP activity or OC levels between the cell sheet group and the positive control group (P > 0.05). TCP constructs wrapped with cell sheets prior to implantation showed bone formation, in contrast to TCP scaffolds alone, which exhibited poor bone formation when implanted, in the subcutaneous layer both in athymic rats and in the sheep.

CONCLUSION

This technique for preparing highly osteoinductive TCP may promote regeneration in large bone defects.

Common Hand Problems with Different Treatments in Countries in Asia and Europe

Common hand problems are treated differently in different countries. This article attempts to bring together the views of surgeons from different countries on some of the most common hand problems that hand surgeons encounter in daily practice. In practice, the correct treatment of these problems may be the most important and influential to patients.