Biomechanical Comparisons of Different Reconstructive Techniques for Scapholunate Dissociation: A Cadaveric Study.

There are many techniques for the treatment of chronic scapholunate dissociation. The three-ligament tenodesis (3LT) is used most widely, but reconstruction of the dorsal ligament alone may not provide sufficient stability. The Mark-Henry technique (MHT) compensates for the insufficient stability of 3LT by additional reconstruction of the volar ligament, but the procedure is complex. The SwiveLock technique (SWT), a recently introduced method, provides stability by using autologous tendons with synthetic tapes, but lacks long-term clinical results. To perform biomechanical comparisons of different reconstructive techniques for scapholunate dissociation using a controlled laboratory cadaveric model. Eleven fresh-frozen upper-extremity cadaveric specimens were prepared. The scapholunate distance, scaphoid rotation, and lunate rotation of the specimens were measured during continuous flexion-extension and ulnar-radial deviation movements. The data were collected using a wrist simulator with a linear guide rail system (tendon load/motion-controlled system) and a motion capture system. Results were compared in five conditions: (1) intact, (2) scapholunate dissociation, (3) SWT, (4) 3LT, and (5) MHT. Paired t-test was employed to compare the biomechanical characteristics of intact wrists to those of scapholunate dissociated wrists, and to those of wrists after each of the three reconstruction methods. SWT and MHT were effective solutions for reducing the widening in scapholunate distance. According to the radioscaphoid angle, all three reconstruction techniques were effective in addressing the flexion deformity of the scaphoid. According to the radiolunate angle, only SWT was effective in addressing the extension deformity of the lunate. In terms of scapholunate angle, only the results after SWT did not differ from those of the intact wrist. The SWT technique most effectively improved distraction intensity and rotational strength for the treatment of scapholunate dissociation. Taking into account the technical complexity of 3LT and MHT, SWT may be a more efficient technique to reduce operating time and minimize complications due to multiple incisions, transosseous tunnels, and complicated shuttling.

Comparison of in-situ release and submuscular anterior transposition of ulnar nerve for refractory cubital tunnel syndrome, previously treated with subfascial anterior transfer-A retrospective study of 24 cases.

BACKGROUND: Although cubital tunnel syndrome is the second most common type of compressive neuropathy in the upper extremities, the indication and optimal surgical method for recurrent or refractory cubital tunnel syndrome remains controversial. This study evaluates the functional outcomes of revision surgery for cubital tunnel syndrome. MATERIAL & METHODS: This study was a retrospective observational multicenter single-institution study including 660 patients who underwent surgery for cubital tunnel syndrome from 2010 to 2019. Among the 660 patients, 42(6.4%) received revision surgery due to remaining or recurrent symptoms confirmed with electromyography(EMG). After excluding those with concurrent elbow fracture, dislocation, osteoarthritis and wound infection, a total of 24 patients were included in the study. The patients were evaluated of disease severity, revision surgical method, time interval to recurrence, underlying diseases and postoperative functional outcomes. RESULTS: All patients received ulnar nerve subfascial anterior transposition for the initial cubital tunnel syndrome surgery. Among the 24 patients (3.7%) who received revision surgery, nine received in situ neurolysis, 12 received submuscular transposition, and three received subcutaneous transfer. 21 patients (88%) reported improved mean VAS score of 4.3, while three patients complained of remaining symptoms that did not improve even after revision surgery. The patients with remaining symptoms all had underlying diabetes mellitus and were treated with subcutaneous transfer. The difference of surgical outcomes between the in situ neurolysis group and the nerve transfer groups were non-significant (p = 0.23). The most common cause of recurrent or persistent symptoms was adhesion and fibrosis at sling area. The mean follow up period before revision surgery was 26.3 months and postoperative follow up period after revision surgery was 8.5 months. CONCLUSION: The outcomes of this study imply that in-situ neurolysis may be as effective as anterior submuscular transfer of ulnar nerve for refractory cubital tunnel syndrome after anterior subfascial transfer.

Coexisting Kienböck's and Preiser's Disease of the Wrist: Experience with Proximal Row Carpectomy with Dorsal Capsular Interposition Technique.

BACKGROUND: Idiopathic avascular necrosis of the lunate is known as Kienböck's disease and that of the scaphoid is known as Preiser's disease. Because the prevalence of coexisting Kienböck's and Preiser's diseases is very low, standardized stages of disease and treatments are not established. CASE PRESENTATION: We report coexisting avascular necrosis of the scaphoid and lunate in a 68-year-old woman with no history of steroids or other risk factors. We treated her with proximal row carpectomy with capsular interposition technique. A distal-based dorsal capsular flap was prepared and repaired the palmar capsule. At the last follow-up, she had no pain and had gained improved range of wrist motion. There was no arthritic change at the newly formed radiocapitate joint. CONCLUSIONS: In the case of collapsed lunate and scaphoid with avascular necrosis, the proximal row carpectomy procedure has an advantage. Proximal row carpectomy with dorsal capsular interposition can be performed when the lunate or scaphoid cannot be saved. Arthritic changes of the capitate head and distal radius lunate facet can be covered with the dorsal capsule.

A Novel Surgical Technique for Neglected Volar Dislocation of the Lunate: Cases Report and Literature Review.

BACKGROUND: Treatments for chronic perilunate or lunate dislocations are very difficult and associated with poor prognoses. There is no established treatment method and are still many controversies. CASE PRESENTATION: We reported three cases of chronic neglected lunate volar dislocation treated with a novel surgical technique. All three cases were males with wrist pain and tingling sensation. Radiographs confirmed chronic volar dislocation of the lunate. Open reduction was performed by combined volar and dorsal approaches. After anatomical reduction, scapholunate and lunotriquetral interosseous ligament reconstructions were performed with the palmaris longus tendon and synthetic tape. The patients had an uneventful postoperative period with satisfactory functional outcomes at the last follow-up. CONCLUSIONS: We believe that open reduction and interosseous ligament reconstruction using the autogenous tendon and synthetic tape may be a valuable option for treating chronic volar dislocation of the lunate.

Pyoderma Gangrenosum of the Hand: Unique Experience and Literature Review.

BACKGROUND: Pyoderma gangrenosum (PG) is a reactive, noninfectious, neutrophilic dermatosis. Diagnosis of PG is based on exclusion, due to lack of availability of a confirmatory test. PG is not caused by infection or gangrene. Misdiagnosis or delayed diagnosis of PG can lead to devastating results. CASE PRESENTATION: In this report, we present a patient with a delayed diagnosis of PG lesion on right hand. Despite initial surgical treatment, the wound was aggravated, and amputation was considered; however, it was eventually treated successfully with an autologous split thickness skin graft. CONCLUSIONS: Knowledge of the PG is essential to actively consider PG in early stage to help facilitate immediate treatment and avoid unnecessary interventions that may worsen the outcome.

Biomechanical Analysis of Three Different Reconstruction Techniques for Scapholunate Instability: A Cadaveric Study.

Background: This study aimed to compare the biomechanical strength of 360° scapholunate interosseous ligament (SLIL) reconstruction only using an artificial material (AM), double dorsal limb (DDL) SLIL reconstruction only using AM, and the modified Brunelli technique (MBT) with ligament. Methods: Eight cadaver wrists were used for this study. The SL interval, SL angle, and radiolunate (RL) angle were recorded with MicroScribe. The SL distance was measured after dividing the volar and dorsal aspects. We utilized four different wrist postures (neutral, flexion, extension, and clenched fist) to compare five conditions: intact wrist, SLIL resection, 360° SLIL reconstruction using AM, DDL SLIL reconstruction using AM, and MBT SLIL reconstruction with ligament. Results: The dorsal SL distance in the SLIL resection was widened in all wrist positions. The dorsal SL distance was restored with all three techniques and in all wrist positions. The volar SL distance in the wrist extension position was widened in the SLIL resection condition. The volar SL distance was restored in the extension position after 360° SLIL reconstruction using AM condition. There were no statistically significant differences in SL and RL angles among the conditions. Conclusions: All three reconstruction techniques could restore the dorsal SL distance. However, only the 360° SLIL reconstruction using AM restored the volar SL distance in the wrist extension position. DDL SLIL reconstruction using AM tended to overcorrect, whereas 360° SLIL reconstruction using AM effectively stopped volar SL interval widening.

Pancarpal dissociation, a very rare type of injury: A case report.

RATIONALE: Pan-carpal dissociation is very rare injury and there is little information as to diagnosis, treatment, and prognosis of this injury. PATIENT CONCERNS: A 35-year-man presented to our hospital with severe pain and swelling of the left wrist and forearm after slipping and falling while riding a motorcycle. DIAGNOSIS: The wrist simple radiographs demonstrated unrecognizable severe fracture-dislocation of the carpal bones concomitant with fractures of the radioulnar shaft. Three-dimensional computed tomography revealed a capitate fracture-dislocation, as well as hamate dislocation, lunotriquetral (LT), and scapholunate (SL) dissociation. These findings suggested pan-carpal dissociation. INTERVENTIONS: To prevent compartment syndrome, fasciotomy, carpal tunnel release, and open reduction and plate fixation for both bone fracture were performed first. Then, for pan-carpal dissociation, the capitate, carpometacarpal joint (CMCJ), and hamate were reduced and fixed first. Then, the SL, LT, and other intercarpal ligaments were repaired. Finally, additional trans-carpal pins to reinforce the ligament repair and 2.0 mm plate to buttress the third CMCJ were fixed. The patient was instructed to begin gentle range of motion exercises of the wrist with pins from four weeks after surgery and all pins were removed at six weeks postoperatively. OUTCOMES: 12 months after the operation, the patient exhibited almost full range of motion with mild pain with VAS (Visual analogue scale) 1-2 at rest and VAS 3-4 with effort. Quick DASH (the disabilities of the arm, shoulder and hand) score was 25 and modified Mayo score was 70. The radiographs demonstrated union of the radioulnar shaft, and the carpal bone alignment was successfully maintained. LESSONS: Pan-carpal dissociation can be diagnosed in patients with capitate fracture-dislocation, hamate dislocation, LT, and SL dissociation. This pattern of injury is very rare and the authors recommend reduction and fixation of the distal carpal row, followed by the proximal row to facilitate an easy approach to the distal carpal row. Although it is very severe injury, rigid anatomical fixation and an early rehabilitation can lead to favorable functional outcomes.

Intraosseous Lipoma of the Carpus: A Report of 2 Cases and a Review of the Literature.

ABSTRACT: Intraosseous lipoma is a very rare benign lipoma, accounting for less than 0.1% of primary bone tumors. Incidentally found in most cases, it frequently involves the metaphysis of the long bones of the lower extremity or calcaneus but rarely occurs in the upper extremity. Intraosseous lipoma of the carpal bones, especially, has yet to be reported, except for 3 cases of scaphoid and capitate involvement. Herein, we report 2 cases of intraosseous lipoma in the capitate and hamate bones with a literature review. Two patients complained of wrist discomfort despite conservative treatment and were diagnosed by computed tomography, magnetic resonance imaging, and surgical biopsy. They were treated with intralesional curettage and autologous bone graft, and their symptoms improved and showed no evidence of recurrence, both clinically and radiologically.

Residual stability of the distal radioulnar joint following ulnar styloid fracture: influence of the remnant distal radioulnar ligaments.

Clinical studies suggest that even untreated basal ulnar styloid fractures may not affect patient outcomes. This may be due to the remaining parts of the distal radioulnar ligament still attached providing sufficient residual stability of the distal radioulnar joint. We tested this hypothesis in a biomechanical cadaveric model. Dorsopalmar translation of the distal radioulnar joint and forearm rotation were measured. Seventeen specimens were tested after a simulated ulnar styloid fracture including the fovea, followed by transection of the remaining palmar (n = 9) or dorsal (n = 8) portions of the distal radioulnar ligament and finally with all remnants transected. Rotation and translation both increased significantly after the final transection compared with the foveal fracture. The increase in translation was larger after transection of the dorsal remnants. We conclude that in an ulnar styloid fracture including the fovea, some ligament components are still attached to the ulnar head, giving residual stability to the distal radioulnar joint.

Novel WTX nonsense mutation in a family diagnosed with osteopathia striata with cranial sclerosis: Case report.

ABSTRACT: Rationale: Osteopathia striata with cranial sclerosis is characterized by linear striations in the metaphysis of the long bones and pelvis with cranial sclerosis. It is an X-linked dominant sclerosing bone dysplasia and affected males show fetal or neonatal lethality. Mutations in the gene encoding Wilms tumor on the X chromosome (WTX) was identified as the cause of X-linked osteopathia striata with cranial sclerosis. About 30 pathogenic mutations in WTX have been reported recently. We have identified a novel nonsense mutation in the family diagnosed as osteopathia striata with cranial sclerosis. PATIENT CONCERNS: The proband came to our attention at age 9 for the evaluation of toe-out gait and planovalgus deformity. Clinically, the proband showed coarse facial features including frontal bossing, ocular hypertelorism, wide depressed nasal bridge, dental malocclusion, mild macrocephaly and low set ears. Radiologically, sclerotic linear striations were seen in the X-rays of the pelvis and the metaphyseal region of femur and tibia and the cranial sclerosis was observed. The proband's mother presented similar facial features and the X-rays of the pelvis, femur, and tibia revealed same sclerotic linear striations as the proband's. DIAGNOSES: Osteopathia striata with cranial sclerosis. INTERVENTIONS: A genetic analysis was conducted on genomic DNA isolated from peripheral blood leukocytes of the proband and the mother for confirming the clinical suspicion of osteopathia striata with cranial sclerosis. WTX on Xq11.2 gene was analyzed in direct sequencing for coding exons including intron-exon boundaries. OUTCOMES: One novel nonsense mutation (c.1003C>T, p.Gln335∗) and known single nucleotide variant were observed in a heterozygous form. LESSONS: We found a novel nonsense mutation in a family diagnosed as osteopathia striata with cranial sclerosis. The relationship between various clinical features and genetic mutations can be clarified by accumulation of genetic database.

The Critical Size of Ulnar Styloid Fragment for the DRUJ Stability.

Background Ulnar styloid fractures can be associated with clinically significant instability of the distal radioulnar joint (DRUJ). However, the exact fragment size that results in DRUJ instability is unknown. Purpose The objective of this study was to determine the critical size of an ulnar styloid fracture that would result in a significant increase in DRUJ translation and forearm rotation. Methods Eight cadaveric specimens were used to investigate the effects of three different ulnar styloid fracture sizes on DRUJ instability: tip fracture, base fracture, and a fracture including the fovea. Forearm rotation and dorsopalmar DRUJ translation were measured after each sequential increase in fracture size. Results Relative to the uninjured state, a significant increase in forearm rotation and dorsopalmar translation was found for all three fractures. However, the fovea fracture showed a statistically significant increase in forearm rotation compared with all other fracture types and a statistically significant increase in total dorsopalmar translation compared with the tip fracture. Conclusion In this study, ulnar styloid fractures involving the fovea resulted in significantly greater DRUJ instability comparted to tip and base fractures alone. This study provides important biomechanical data regarding the critical size of ulnar styloid fractures that result in DRUJ instability and may aid in the surgical decision-making algorithm in these patients.

Scapholunate and lunotriquetral interosseous ligament augmentation with internal bracing in perilunate dislocation: Case reports.

RATIONALE: The goals of surgical treatment of the perilunate dislocation (PLD) are confirmation of reduction, ligament repair, and supplemental fixation of the bony architecture. Open reduction and direct repair of the torn ligament are recommended for acute PLD. However, repair of the scapholunate interosseous ligament (SLIL) and lunotriquetral interosseous ligament (LTIL) is often unreliable, and secure repair is challenging. Internal bracing (IB) is an augmentation method that uses high-strength non-absorbable tape and enhances strength and support during the critical period of ligamentous healing. However, there is a paucity of data on the application of IB for PLD in the wrist. We report 3 cases of PLD that were augmented with IB after SLIL and LTIL repair. PATIENT CONCERNS: All 3 cases were men who visited our emergency department with wrist after falling off a ladder. DIAGNOSES: Initial radiographs revealed a dorsal PLD. INTERVENTIONS: Surgically, complete rupture of the SLIL and LTIL were confirmed. K-wires were placed into the scaphoid and lunate and used as joysticks to correct the intercalated segment instability pattern. This usually requires correcting scaphoid flexion and lunate extension and closing the scapholunate interval. Prior to SLIL and LTIL repair, temporary intercarpal fixation was performed with K-wires to maintain the carpal relationship. The dorsal SLIL and LTIL were carefully repaired using suture anchors. However, ligament repair was unreliable, and insecure. In view of the likelihood of insufficient repair, we performed IB augmentation using synthetic tape. OUTCOMES: At the last follow-up, all cases were pain-free and had returned to all activities. The last follow-up radiographs showed good alignment of the carpal bones and no arthritic changes. LESSONS: IB augmentation can reduce the period of K-wire fixation and cast immobilization and can enable early joint motion. We believe that interosseous ligament augmentation using IB is a reasonable treatment option for PLD.

Kinematic analysis of two scapholunate ligament reconstruction techniques.

PURPOSE: This study compares the kinematic changes after the procedures for scapholunate interosseous ligament (SLIL) reconstruction-the modified Brunelli technique (MBT) and Mark Henry's technique (MHT). METHODS: Ten cadaveric wrists were used. The scapholunate (SL) interval and angle and radiolunate (RL) angle were recorded using the MicroScribe system. The SL interval was measured by dividing the volar and dorsal portions. Four motions of the wrist were performed-neutral, flexion, extension, and clenched fist (CF) positions-and compared among five conditions: (1) intact wrist, (2) volar SLIL resection, (3) whole SLIL resection, (4) MBT reconstruction, and (5) MHT reconstruction. RESULTS: Under the whole SLIL resection condition, the dorsal SL intervals were widened in all positions. In all positions, the dorsal SL intervals were restored after MBT and MHT. The volar SL interval widened in the extension position after volar SLIL resection. The volar SL interval was not restored in the extension position after MBT and MHT. The SL angle increased in the neutral and CF positions under the whole SLIL resection condition. The SL angle was not restored in the neutral and CF positions after MBT and MHT. The RL angle increased in the neutral and CF positions under the whole SLIL resection condition. The RL angle was not restored in the neutral and CF positions after MBT and MHT. CONCLUSION: The MBT and MHT may restore the dorsal SL interval. No significant differences in restoration of the SL interval between MBT and MHT were found in the cadaveric models. CLINICAL RELEVANCE: No significant differences between MBT and MHT were found in the cadaveric models for SLIL reconstruction. When considering the complications due to volar incision and additional procedures in MHT, MBT may be a more efficient technique in terms of operative time and injury of the anterior structures during surgery, but further research is needed.

Comparison of Three Different Internal Brace Augmentation Techniques for Scapholunate Dissociation: A Cadaveric Biomechanical Study.

Internal bracing (IB) is an augmentation method using high-strength nonabsorbable tape. However, there is no detailed information about the direction, location, or number of IBs required for scapholunate interosseous ligament (SLIL) injury repair. Thus, this study compared the biomechanical characteristics of short-transverse IB, long-oblique IB, and the combination of short-transverse and long-oblique (Combo) IB for SLIL injury in a biomechanical cadaveric model. We prepared nine fresh-frozen full upper extremity cadaveric specimens for this study. The scapholunate distance, scapholunate angle, and radioscaphoid angle were measured using the MicroScribe digitizing system with the SLIL intact, after scapholunate dissociation and the three different reconstructions. Three-dimensional digital records were obtained in six wrist positions in each experimental condition. Short-transverse IB had a similar effect compared with long-oblique IB in addressing the widening of the scapholunate distance. However, both were less effective than Combo IB. For scaphoid flexion deformity, short-transverse IB had minimal effect, while long-oblique IB had a similar effect compared to Combo IB. Combo IB was the most effective for improving distraction intensity and rotational strength. This study provides important information about the biomechanical characteristics of three different IB methods for SLIL injury and may be useful to clinicians in treating scapholunate dissociation.

Importance of detection of capitellar cartilage injuries concomitant with isolated radial head fractures: A retrospective clinical study.

OBJECTIVE: This study aimed to analyze the injury pattern and clinical importance of concomitant capitellar cartilage defects (CCDs) among patients treated surgically for radial head fracture (RHF). METHODS: A total of 74 patients who were treated surgically for isolated RHFs were retrospectively reviewed. Of these, 12 patients with CCDs (16.2%) were classified as Group I (10 men; mean age, 41.3±12.8 years) and the remaining 62 patients without CCD as Group II (control group) (48 men; mean age, 50.8±13 years). The mean follow-up was 21.3±3.2 months in Group I and 18.7±6.4 in Group II. In Group I, 11 patients underwent open reduction and internal fixation, whereas 1 patient was treated by radial head resection. The preoperative range of motion (ROM) was recorded; the severity of RHF was assessed using the Mason classification. The location, size, and thickness of CCD injuries at the time of surgery were also documented. At the final follow-up, radiological assessment was performed to determine the bone union, and clinical measurements, including ROM and the Mayo elbow performance score (MEPS), were performed. The clinical features of the 2 groups were statistically analyzed. RESULTS: In Group I, 10 patients showed limited forearm rotation. CCD was located posterolaterally in 11 patients and anterolaterally in 1 patient. At the final follow-up, 11 patients from Group I who underwent open reduction and internal fixation showed complete union of RHF and full recovery of pronation and supination. According to the MEPS, 9 patients exhibited excellent results, and 3 patients exhibited good results. In Group I, RHFs were classified as Mason type II in 7 patients (58.3%) and type III in 4 patients (58.3%). In Group II, RHFs were type II in 45 patients (72.6%) and type III in 17 patients (27.4%). In comparative analyses, there was a significant difference in age (41.3±12.8 versus 50.8±13.0, p=0.041) between the 2 groups. Preoperative pronation/supination was higher in Group II (131.7±36.2) than in Group I (106.3±31.6) (p=0.021). There were no significant differences in sex (p=0.097), follow-up period (p=0.326), Mason type (p=0.482), preoperative extension/flexion (102.3±43.3 [Group I] versus 107.6±44.9 [Group II]) (p=0.584), final follow-up extension/flexion (133.3±10.7 [Group I] versus 126.9±21.2 [Group II]) (p=0.384), pronation/supination (151.2±9.1 [Group I] versus 151.2±13.3 [Group II]) (p=0.558), and the MEPSs (92.9±6.6 [Group I] versus 93.3±7.5 [Group II]) (p=0.701). CONCLUSION: If a thorough physical examination of a patient with RHF reveals limited forearm rotation, effort must be made to identify the cause, and the possibility of CCD must be considered. Moreover, there is a need for careful observation during RHF surgery for not only fracture reduction or fixation but also possible CCD. LEVEL OF EVIDENCE: Level III, Therapeutic Study.

Simultaneous ipsilateral distal radius and radial head fractures: Two case reports of radius bipolar fracture.

RATIONALE: Distal radius fracture with simultaneous ipsilateral radial head fracture is a very rare pattern of injury. This type of injury is referred to as 'radius bipolar fracture'. Treatments for this injury pattern can be challenging because both the wrist and elbow need to be considered. There are currently no guidelines for the treatment of this specific type of injury. We report two cases of this unusual pattern of injury treated in our hospital. PATIENT CONCERNS: Case 1 was a 78-year-old female patient and case 2 was a 19-year-old female patient who visited our emergency department with left elbow and wrist pain after slipping and falling. DIAGNOSIS: Plain radiography and computed tomography revealed radius bipolar fracture. Case 1 had an AO type C3 distal radius fracture, a Mason type III radial head fracture. Case 2 had an AO type B2 undisplaced distal radius fracture and a Mason type III radial head fracture. INTERVENTIONS: In case 1, open reduction and internal fixation (ORIF) was performed for the distal radius fracture and radial head replacement arthroplasty for the radial head fracture. In case 2, distal radius fracture was treated conservatively and ORIF was performed for the radial head fracture. OUTCOMES: Bony union as achieved in both cases. At 1-year follow-up, case 1 showed slight limited range of motion of the wrist. Case 2 showed no radius shortening and full range of motion of the wrist and elbow. The Quick disabilities of the arm, shoulder and hand score was 18 and 16, respectively. LESSONS: After this type of injury, the radius length can be changed, and as a result, ulnar variance can be affected. When radial head replaced is considered, it would be better to operate on the wrist first, and then perform radial head replacement. In this way, radiocapitellar overstuffing or instability can be prevented. However, if ORIF is planned for proximal radius fracture, either the proximal or distal radius can be fixed first. Surgeons should try to preserve radial length during treatment to optimize patient outcomes.

Volar Plate Capsulodesis With Internal Brace Augmentation for the Claw Hand.

Claw hand deformity is characterized by hyperextension of the metacarpophalangeal joints and flexion of the proximal interphalangeal joints. Surgical treatment of claw hand deformities often involves soft tissue procedures such as tendon transfers or volar plate capsulodesis. However, tissue attenuation over time can lead to recurrence of the deformity. Augmentation with an internal brace may help to address this problem. This report presents a novel technique for the treatment of claw hand deformity involving augmentation of the traditional volar plate capsulodesis with internal brace. Two illustrative cases utilizing the described technique are presented.

Treatment of purely ligamentous dorsoulnar radiocarpal dislocation with ulnar translation of the carpus: A case report.

RATIONALE: Radiocarpal fracture-dislocations are extremely infrequent injuries caused by high-energy trauma and involve significant osseous and ligamentous injuries. If not treated properly, it can lead to serious complications such as ulnar translation of the carpus, multidirectional instability, loss of motion, and post-traumatic arthritis. Purely ligamentous injuries are rarer than fracture-dislocation injuries. Because previous studies have reported small patient cohorts, there has been no standardized treatment strategy for purely ligamentous radiocarpal dislocation. PATIENT CONCERNS: A 24-year-old man suffered a left wrist injury in a motorcycle accident. Plain radiographs revealed dorso-ulnar radiocarpal dislocation without radial fracture and Carpal-ulnar distance ratio (CUDR) was 0.16. MRI scans showed the disruption of the dorsal ligaments and capsules and avulsed from the proximal insertion of the volar radiocarpal ligaments. DIAGNOSIS: Dorsoulnar radiocarpal dislocation with purely ligamentous injury. INTERVENTION: We removed the interposing chondral fragment from the radiocarpal joint and repaired the radioscaphocapitate (RSC) and radiolunate (RL) ligaments with the Jugger Knot Soft Anchor Suture (Biomet, Inc, Warsaw, IN) and applied additional radiocarpal K-wires and an external fixator to maintain reduction and optimal ligament tension. OUTCOMES: The patient showed good clinical results although ulnar translation of the carpus recurred in radiological follow-up. LESSONS: Aggressive surgical management is needed earlier in the treatment of purely ligamentous radiocarpal dislocation, especially if the ulnar translation of the carpus was observed in the initial radiographs.

Anterior Interosseous Nerve Syndrome: Is it a Compressive Neuropathy?

BACKGROUND: Anterior interosseous nerve (AIN) syndrome is a rare disease whose pathophysiology is controversial. Despite efforts to elucidate the pathophysiology of AIN syndrome, it has not yet been resolved. We reinterpret electrodiagnostic studies, magnetic resonance imaging (MRI), and surgical findings to clarify the pathophysiology of AIN syndrome. MATERIALS AND METHODS: In this retrospective case series, we included surgically treated 20 cases of nontraumatic AIN syndrome. Surgery was performed after a minimum of 12 weeks of conservative treatment. The clinical data and operation records were extracted from the medical records for analysis. All electrodiagnostic tests were reinterpreted by physicians with an American Board Certification in electrodiagnostic medicine. Moreover, every contrast-enhanced MRI performed during the assessment was reviewed by a musculoskeletal radiologist. RESULTS: Of the twenty re-analyzed cases, nine AIN syndromes (45%) showed abnormal electromyography in non-AIN innervated muscles. Sensory nerve conduction studies were normal in all cases. Five magnetic resonance images (46%) showed signal changes in non-AIN-innervated muscles. Only four cases (20%) revealed definitive compression of the AIN during surgery. CONCLUSIONS: Electrodiagnostic study and MRI indicated that many patients with AIN syndrome exhibited a diffuse pathologic involvement of the motor component of the median nerve. We conclude that the main pathophysiology of AIN syndrome would be diffuse motor fascicle neuritis of the median nerve in the upper arm.

Carpal Tunnel Syndrome Caused by Lipofibromatous Hamartoma of the Median Nerve.

Lipofibromatous hamartoma (LFH) is a rare tumor of the peripheral nerves, which usually involves the median nerve. The authors reported on two rare cases of carpal tunnel syndrome due to LFH of the median nerve. A 49-year-old female patient complained of the mass and symptoms consistent with LFH. Magnetic resonance imaging (MRI) showed typical LFH findings. The symptoms were successfully ameliorated with carpal tunnel release and external neurolysis. A 37-year-old female patient complained of weakening thumb abduction and the mass where the MRI showed atypical findings. Opponensplasty and debulking operations were performed after which thumb abduction was improved; however, neurological sequelae remained. LFH of the median nerve is managed on a case-by-case basis as treatment guidelines are not very clearly defined yet. However, the less invasive treatment such as carpal tunnel release and external neurolysis than more aggressive surgical treatment should be recommended as a treatment option.