A comparative study of the effect of drilling depth on generation of compressive force by headless compression screws using conical and cylindrical type of drill bit

BACKGROUND: This study was conducted to measure the effect of different drilling depths on compression forces generated by two commonly used headless compression screws using the two different types of drill bit, the Acutrak® mini (conical type drill bit) and the Synthes 3.0 HCS® (cylindrical type drill bit). METHODS: A load cell was placed between two Sawbone blocks, which were 12 mm and 40 mm in thickness, respectively. After placing the guide pin into the center of the block, the drilling depth of the Acutrak® mini and Synthes HCS® screws ranged from 16 to 28 mm and 22 to 28 mm, respectively. The 24-mm screws were inserted and the compression force was measured immediately and at 30 min post-insertion. RESULTS: The Acutrak® mini generated greater compression force compared to the Synthes 3.0 HCS® when drilled to a depth of less than 24 mm. The compression force of the Acutrak® mini showed a strong inverse correlation with the drilling depth. There was no significant inverse correlation observed between the compression force of the Synthes HCS® and the drilling depth. CONCLUSIONS: If the screw length and the drill depth are the same, the Synthes 3.0 HCS® (cylindrical type drill bit) is safer and easier to use as it has no change in the compression force even when over-drilling because the compression force of the two screws is similar. As for the Acutrak® mini (conical type drill bit), while it is technically demanding due to varying compression force according to the drill depth, it can be used in certain cases because it can give stronger compression force through under-drilling.ope

Trans-scaphoid Perilunate Fracture Dislocation

Trans-scaphoid perilunate fracture dislocations, which account for more than half of total cases of perilunate injuries, are common in young patients and occur as a result of high-energy injuries, and improper management can impair wrist alignment and function. Understanding the related wrist anatomy and pathomechanics may help surgeons evaluate and diagnose patients. Early operation to reduce and fix the injuries should be considered to achieve optimal clinical and radiological outcomes. In this re view article, we present an overview of wrist pathoanatomy, the pathomechanics of trans-scaphoid perilunate fracture dislocations, operative treatment options including an arthroscopic procedure, and reported clinical and radiological outcomes.ope

척측 수근 신건의 탈구에 대한 수술적 치료

Purpose : Extensor carpi ulnaris (ECU) subluxation has a low incidence rate, to date, there has only been a few studies evaluating the operative treatment for type of injury. The purpose of this study was to retrospectively analyze 11 patients with ECU subluxation who underwent operative treatment. Materials and Methods : Between March 2005 and February 2015, 11 patients received operative treatment. Magnetic resonance imaging and dynamic ultrasound were used to make the diagnosis. ECU subluxation patterns were classified by the Inoue's classification system. There were two cases of type A, one case of type B, five cases of type C, and three cases unfit for Inoue's classification. We also found two cases of radial subluxation and one case of ulnar locked subluxation. In type A and B cases, ECU tendons were relocated then sheaths repair was performed, and the extensor retinaculum reconstruction was performed. In type C cases, the fibro-osseous sheaths were fixed. In the three unclassified cases, extensor retinaculum reconstruction was performed. In all cases, fibro-osseous sheaths were fixed using the anchor suture technique. We compared the clinical results based on the following: motion range of the wrist joint; grip strength; visual analogue scale (VAS) score; quick disabilities of the arm, shoulder and hand (Q-DASH) score; and Mayo wrist score. Results : The median age of patients at the time of the operation was 32 years, and the average follow-up period was 11.2 months. There were five cases of triangular fibrocartilage complex tear, two cases of distal radioulnar joint instability, three cases of ECU split tear as accompanying injury. There were significant differences in the clinical results. The average motion range of the wrist increased compared with the preoperative value (84.7% to 92.4% compared to contralateral normal side). The postoperative VAS score, Q-DASH score and Mayo wrist score showed better results compared with the respective preoperative values (6.0 to 1.1, 40.9 to 12.4, 75.9 to 86.4). Conclusion : ECU subluxation is a rare occurrence. Dynamic ultrasound is useful in diagnosing ECU tendon subluxation. Satisfactory results can be obtained with the use of a proper technique, which depends on the type of subluxation.ope

WNT-modulating gene silencers as a gene therapy for osteoporosis, bone fracture, and critical-sized bone defects

Treating osteoporosis and associated bone fractures remains challenging for drug development in part due to potential off-target side effects and the requirement for long-term treatment. Here, we identify recombinant adeno-associated virus (rAAV)-mediated gene therapy as a complementary approach to existing osteoporosis therapies, offering long-lasting targeting of multiple targets and/or previously undruggable intracellular non-enzymatic targets. Treatment with a bone-targeted rAAV carrying artificial microRNAs (miRNAs) silenced the expression of WNT antagonists, schnurri-3 (SHN3), and sclerostin (SOST), and enhanced WNT/b-catenin signaling, osteoblast function, and bone formation. A single systemic administration of rAAVs effectively reversed bone loss in both postmenopausal and senile osteoporosis. Moreover, the healing of bone fracture and critical-sized bone defects was also markedly improved by systemic injection or transplantation of AAV-bound allograft bone to the osteotomy sites. Collectively, our data demonstrate the clinical potential of bone-specific gene silencers to treat skeletal disorders of low bone mass and impaired fracture repair.ope

Accuracy of Conventional Triplane Measures Compared to 3-D Analysis for Assessment of Cubitus Varus Deformities in Adults

Purpose: Cubitus varus is a common triplane deformity in adults associated with supracondylar humeral fractures experienced as a child and consists of varus, extension, and internal rotation components. When corrective osteotomy is indicated, these three components should be measured precisely. This study aimed to evaluate the accuracy of radiographic and physical measurements of cubitus varus deformities in adults compared to values measured on three-dimensional (3-D) bone surface models of the adult bilateral humerus. Methods: Three-dimensional bilateral humerus models were developed using bilateral humerus CT images of 20 adult patients with cubitus varus. The varus, internal rotation, and extension components of the deformity were assessed by superimposing the 3-D bone model onto a mirror-image model of the contralateral normal humerus. Values obtained from the radiographic and physical measurements were compared with those from the 3D model. The reliability of each measurement was assessed by calculating correlation coefficients (CCs). Results: Radiographic measurements of the varus and extension components showed good reliability (CC = 0.796 and 0.791, respectively). Physical measurement of the varus component, however, showed only moderate reliability (CC= 0.539), while physical measurement of the extension and internal rotation components exhibited poor reliability (CC = 0.164 and 0.466, respectively). Conclusion: Varus and extension components of cubitus varus in adults can be reliably measured using conventional methods, whereas the internal rotation component cannot. Thus, 3-D methods with which to quantify the rotational component preoperatively might be needed when the correction of a rotational deformity is considered.ope

Operative Treatment for Nonunion of the Distal Scaphoid

Purpose: The purpose of this study was to analyze the clinical and radiological outcomes of distal scaphoid nonunion patients who underwent operative treatment. Methods: From July 2006 to May 2014, there were a total of 9 distal scaphoid nonunion patients, with a mean age of 32 years. The mean time from symptom onset to operation was 15 months. Operative treatment was performed through a volar approach, osteosynthesis with an auto-iliac bone graft was performed. Union was determined through radiographs and computed tomography, while the scapholunate angle (SLA) and lateral intrascaphoid angle (LISA) were measured. Clinical outcomes were evaluated by assessing range of motion (ROM) of the wrist, the visual analogue scale (VAS), Mayo wrist score, and disabilities of arm, shoulder and hand (DASH) score. Results: The incidence of distal scaphoid nonunion was 11.8% (9/76), with all patients demonstrating union after the operation. Mean union time was 5 months and mean follow-up period was 23 months. Both SLA and LISA decreased, returning to normal range. The ROM of the wrist joint increased but not statistically significant. The postoperative VAS pain score improved, while grip strength advanced. In addition, both postoperative Mayo wrist and DASH scores document better results than those of pre-operation. Overall, there were two postoperative complication cases of joint motion limitation and pin site irritation. Conclusion: Osteosynthesis with auto-iliac bone graft for nonunion of the distal scaphoid showed good clinical and radiological outcomes. Thus, it is considered a recommendable operation in the treatment of distal scaphoid nonunion.ope

Ulnar nerve stability-based surgery for cubital tunnel syndrome via a small incision: a comparison with classic anterior nerve transposition

OBJECTIVE: The purpose of this study was to compare the clinical outcomes of ulnar nerve stability-based surgery via a small incision with those of classic anterior transposition of the ulnar nerve for cubital tunnel syndrome. METHODS: From March 2008 to December 2013, 107 patients with cubital tunnel syndrome underwent simple decompression or anterior transposition via a small incision, according to an ulnar nerve stability-based decision based on an assessment of intraoperative ulnar nerve stability (group A, n = 51), or anterior transposition via a classic incision (group B, n = 56). Clinical outcome was assessed using grip and pinch strength, two-point discrimination, the mean of the disabilities of arm, shoulder, and hand (DASH) survey, and the modified Bishop scale. RESULTS: At the final follow-up, all outcome measures improved significantly in both groups and there were no significant differences between the two groups. However, there were fewer operation-related complications in group A (one revision surgery) than in group B (one superficial infection, two painful scars, and five cases of numbness at the medial elbow). CONCLUSIONS: Outcomes after the ulnar nerve stability-based approach and anterior transposition were similar, although more patients experienced operation-related complications after anterior transposition via a classic incision. Making an ulnar nerve stability-based decision to perform either simple decompression or anterior transposition via a small incision seems to be a better strategy for patients with cubital tunnel syndrome.ope

Correlation between change in muscle excursion and collagen content after tendon rupture and delayed repair

BACKGROUND: The objectives of the present study were to compare changes in muscle excursion, total collagen, and collagen subtypes after tenotomy over time and after delayed tendon repair. METHODS: Tenotomy on the extensor digitorum tendon of the right second toes of 48 New Zealand White rabbits was performed; toes on the left leg were used as controls. Passive muscle excursion, total collagen content, and type I, III, and IV collagen contents were measured at 1, 2, 4, and 6 weeks after tenotomy. Next, passive muscle excursion and total collagen content were measured at 8 weeks after delayed tendon repair at 1, 2, 4, and 6 weeks after a tenotomy. RESULTS: Passive muscle excursion decreased sequentially over time after tenotomy. Meanwhile, total collagen increased over time. These changes were significant after 4 weeks of injury. Type I collagen significantly increased, type III collagen significantly decreased, and type IV collagen had no significant change over time. Passive muscle excursion was negatively correlated with total collagen and type I collagen after tenotomy at each time point after tenotomy (p < 0.05). After tendon repair, increases in total collagen content after tenotomy were not reversed, despite early repairs at 1 and 2 weeks after tenotomy. CONCLUSIONS: Increases in type I collagen were found to be associated with decreased excursion after tendon rupture. The increase in collagen that was observed after tenotomy was not reversed by repair within 8 weeks.ope

Factors Influencing Outcomes after Ulnar Nerve Stability-Based Surgery for Cubital Tunnel Syndrome: A Prospective Cohort Study

PURPOSE: Simple decompression of the ulnar nerve has outcomes similar to anterior transposition for cubital tunnel syndrome; however, there is no consensus on the proper technique for patients with an unstable ulnar nerve. We hypothesized that 1) simple decompression or anterior ulnar nerve transposition, depending on nerve stability, would be effective for cubital tunnel syndrome and that 2) there would be determining factors of the clinical outcome at two years. MATERIALS AND METHODS: Forty-one patients with cubital tunnel syndrome underwent simple decompression (n=30) or anterior transposition (n=11) according to an assessment of intra-operative ulnar nerve stability. Clinical outcome was assessed using grip and pinch strength, two-point discrimination, the mean of the disabilities of arm, shoulder, and hand (DASH) survey, and the modified Bishop Scale. RESULTS: Preoperatively, two patients were rated as mild, another 20 as moderate, and the remaining 19 as severe according to the Dellon Scale. At 2 years after operation, mean grip/pinch strength increased significantly from 19.4/3.2 kg to 31.1/4.1 kg, respectively. Two-point discrimination improved from 6.0 mm to 3.2 mm. The DASH score improved from 31.0 to 14.5. All but one patient scored good or excellent according to the modified Bishop Scale. Correlations were found between the DASH score at two years and age, pre-operative grip strength, and two-point discrimination. CONCLUSION: An ulnar nerve stability-based approach to surgery selection for cubital tunnel syndrome was effective based on 2-year follow-up data. Older age, worse preoperative grip strength, and worse two-point discrimination were associated with worse outcomes at 2 years.ope

Limited Dorsal Approach for Intra-Articular Distal Radius Fracture Involving the Sigmoid Notch

Purpose: The purpose of this study was to analyze the 16 patients, with distal radius fracture involving sigmoid notch fracture, who were treated by limited dorsal approach retrospectively. Methods: Between June 2003 and December 2013, 743 patients with distal radius fracture underwent operative treatment. Among them, 16 patients received conventional treatment, with additional limited dorsal approach. The fracture patterns involved sigmoid notch with dorsal lunate fossa depression, as well as distally displaced dorsal rim fragment. Radiologic results were evaluated based on dorsal tilt, radial inclination, and radial shortening. Clinical results were evaluated based on grip strength, motion range of the wrist joint, arm disabilities, shoulder & hand (DASH) score, and visual analogue scale (VAS) score. Results: The average radial inclination was 21°, with 5.6° of volar tilt and 0.1 mm of radial shortening. The average range of motion were 42.6° of flexion, 56.5° of extension, 23.4° of radial tilt, and 24.8° of ulnar tilt. The average grip strength was 81.3% of the opposite side. The average VAS and DASH scores were 1.1 and 21.3, respectively. Conclusion: In the case of sigmoid notch fracture involving dorsal lunate fossa depression fractures and distally displaced dorsal rim fractures, we were able to reduce and fix the fragment conveniently using limited dorsal approach.ope