Biomechanical analysis of plate versus K-wire fixation for metacarpal shaft fractures with wedge-shaped bone defects.

BACKGROUND: Metacarpal shaft fracture is a common type of hand fracture. Numerous studies have explored fixing transverse fractures in the midshaft of the metacarpal bone. However, this section of the metacarpal bone is often susceptible to high-energy injury, resulting in comminuted fracture or bone loss. In such cases, wedge-shaped bone defects can develop in the metacarpal shaft, increasing the difficulty of performing fracture fixation. Notably, the research on this type of fracture fixation is limited. This study compared the abilities of four fixation methods to fix metacarpal shaft fractures with wedge-shaped bone defects. METHODS: In total, 28 artificial metacarpal bones were used. To create wedge-shaped bone defects, an electric saw was used to create metacarpal shaft fractures at the midshaft of each bone. The artificial metacarpal bones were then divided into four groups for fixation. The bones in the first group were fixed with a dorsal locked plate (DP group), those in the second group were fixed with a volar locked plate (VP group), and those in the third group were fixed by combining dorsal and volar locked plates (DP + VP group), and those in the fourth group were fixed with two K-wires (2 K group). Cantilever bending tests were conducted using a material testing machine to measure yielding force and stiffness. The four groups' fixation capabilities were then assessed through analysis of variance and Tukey's test. RESULTS: The DP + VP group (164.1±44.0 N) achieved a significantly higher yielding force relative to the 2 K group (50.7 ± 8.9 N); the DP group (13.6 ± 3.0 N) and VP group (12.3 ± 1.0 N) did not differ significantly in terms of yielding force, with both achieving lower yielding forces relative to the DP + VP group and 2 K group. The DP + VP group (19.8±6.3 N/mm) achieved the highest level of stiffness, and the other three groups did not differ significantly in terms of stiffness (2 K group, 5.4 ± 1.1 N/mm; DP group, 4.0 ± 0.9 N/mm; VP group, 3.9 ± 1.9 N/mm). CONCLUSIONS: The fixation method involving the combined use of dorsal and volar locked plates (DP + VP group) resulted in optimal outcomes with respect to fixing metacarpal shaft fractures with volar wedge bone defects.

Percutaneous treatment of type C distal radius fractures using dual-external fixator.

BACKGROUND: This study aimed to introduce a potential alternative percutaneous treatment for AO types C1, C2, and C3 distal radius fractures using dual-external fixator (a no-bridging cemented-pin frame and a conventional wrist-bridging external fixator). MATERIALS AND METHODS: From January 2018 to January 2021, 52 patients (52 distal radius fractures) were treated with dual-external fixator. For comparison, 61 patients (61 distal radius fractures) were treated with a plate and screw system. Wrist function was assessed using the Mayo Wrist Score. Patient satisfaction was assessed using the Short Assessment of Patient Satisfaction. A P < 0.05 was considered statistically significant. RESULTS: Fracture healing was achieved in all patients. At the final follow-up of 29 months (range, 24-34 months) vs 36 months (range, 26-39 months) (P > 0.05), the patients treated with dual-external fixator and a plate and screw system achieved mean ulnar deviations of 31° vs 29° (P < 0.05), mean Mayo Wrist Scores of 91.12 ± 5.98 vs 88.12 ± 7.54 (P < 0.05), and mean patient satisfaction scores of 23.42 ± 2.47 vs 23.04 ± 2.32 (P > 0.05). CONCLUSIONS: AO types C1, C2, and C3 distal radius fractures can be treated successfully using dual-external fixator. The technique is a potential alternative in addition to the conventional treatments. LEVEL OF EVIDENCE: Level IIa.

Usefulness of multiple bioabsorbable Mg screws/K­wires for comminuted radial head fractures.

PURPOSE: We hypothesized that multiple absorbable screws/K-wires would be effective for native head preservation in comminuted radial head fracture fixation (com-RHFs). METHODS: Seventeen patients who met the inclusion criteria between 2018 and 2020 were included. Radiologic findings indicating proper union and clinical outcomes such as the range of elbow motion, visual analog scale score, and Mayo Elbow Performance Score were assessed prospectively after surgery and at least three years of follow-up. RESULTS: The mean follow-up period was 4.6 years. Eleven, one, three, and two patients presented with isolated com-RHFs, type 2 (accompanied injury of medial collateral ligament), type 4 ("terrible triad") fractures, and type 5 posterior olecranon fracture-dislocations, respectively. Union was achieved after a mean of nine weeks postoperatively. The head and shaft angles did not differ significantly from the contralateral normal values (p = 0.778 and 0.872, coronal and sagittal, respectively). At the final follow-up, the mean flexion-extension/pronation-supination arcs were 126.47 ± 4.92°/135.59 ± 10.13°, and thus were significantly different from those on the contralateral side (p < 0.001, both), however the arcs were functional ranges for ordinary daily life. Also, functional status was satisfactory in all individuals. The arthritis grade and extent of heterotrophic ossification were satisfactory in all cases, and there were no serious complications requiring revision surgery. CONCLUSIONS: Absorbable screw/K-wire fixation for com-RHFs is an option before radial head arthroplasty associated with a low complication rate and no need for revision.

Analyzing the reduction quality of the distal radioulnar joint after closed K-wire transfixation in a cadaver model: is supination or neutral position superior?

INTRODUCTION: Distal radioulnar joint (DRUJ) instabilities are challenging and their optimal treatment is controversial. In special cases or when reconstruction of the stabilizing triangular fibrocartilage complex (TFCC) fails, K-wire transfixation can be performed. However, no consensus has been reached regarding the rotational position of the forearm in which this should be done. Therefore, it was investigated whether anatomical reduction would best be achieved by transfixation in neutral position or supination of the forearm. MATERIALS AND METHODS: Twelve cadaveric upper limbs were examined before dissection of the DRUJ stabilizing ligaments and after closed transfixation in both positions by C-arm cone-beam CT. Whether this was first done in neutral position or in supination was randomized. The change in the radioulnar ratio (RR) in percentage points (%points) was analyzed using Student's t-test. RR was used since it is a common and sensitive method to evaluate DRUJ reduction, expressing the ulnar head's position in the sigmoid notch as a length ratio. RESULTS: The analysis showed an increased change in RR in neutral position with 5.4 ± 9.7%points compared to fixation in supination with 0.2 ± 16.1%points, yet this was not statistically significant (p = 0.404). CONCLUSIONS: Neither position leads to a superior reduction in general. However, the result was slightly closer to the anatomical position in supination. Thus, transfixation of the DRUJ should be performed in the position in which reduction could best be achieved and based on these data, that tends to be in supination. Further studies are necessary to validate these findings and to identify influential factors.

Surgical Treatment for Isolated Closed Multi-metatarsal Fractures: At Least 2-Year Outcomes in 79 Feet.

Multimetatarsal fractures are a particular type possibly associated with worse functional outcomes. Existing studies are scarce, fragmented, and lack control for confounders. This study aimed to explore the functional prognosis of isolated closed extra-articular multimetatarsal fractures and the different outcomes between the plate-screw and K-wire fixation. This retrospective study included 79 patients who underwent surgery for isolated closed extra-articular multimetatarsal fractures from May 2017 to December 2020. We recorded baseline characteristics. The primary outcome measure was Visual Analogue Scale (VAS), American Orthopedic Foot and Ankle Society (AOFAS) score, and Foot and Ankle Outcome Score (FAOS). Exploratory correlation analysis of the variables with VAS, AOFAS score, and FAOS was performed. The differences between the plate-screw group (n = 58) and K-wire group (n = 21) were compared. Seventy-nine patients (79 feet) were included with a follow-up of (47.3 ± 12.7) months (range, 26-70). Full weight bearing time was (11.7±5.3) weeks. VAS was (1.4±1.8) points, AOFAS score was (86.4±13.3) points, and FAOS was (79.0±11.1) points. Complications were observed in 17 cases (21.5%). According to exploratory correlation analysis, VAS was weakly associated with fixation method and gender, AOFAS was weakly associated with fixation method, FAOS was weakly associated with trauma mechanism. When the plate-screw group (n = 58) was compared with the K-wire group (n = 21), we found the former was superior to the latter in terms of full weight bearing time, VAS, AOFAS score, and malunion rate (all p < .05). FAOS was nonsignificant (p = .056). Operative treatment of isolated closed extra-articular multimetatarsal fractures showed good mid-term results. Plate-screw fixation was associated with faster rehabilitation as well as a lower malunion rate. The mid-term follow-up results showed patients with plate-screw fixation had better VAS and AOFAS scores.

Minimally Invasive Versus Open Hammertoe Correction: A Retrospective Comparative Study.

Hammertoe deformity is a common forefoot pathology, characterized by a progressive deformity with dorsiflexion of the proximal phalanx on the metatarsal head at the metatarsal phalangeal joint (MTPJ) and plantarflexion of the intermediate phalanx on the proximal phalanx at the proximal interphalangeal joint (PIPJ). While there is literature available discussing open techniques for hammertoe correction, there is a lack of publications discussing minimally invasive techniques, therefore the objective of this retrospective comparative study is to evaluate minimally invasive versus open hammertoe surgery in terms of time to osseous union, complications, recurrence, and return to full activity. Sixty eight feet among 41 patients met the inclusion criteria and were surveyed. Among the 68 feet, 54 feet (124 toes) underwent minimally invasive hammertoe correction and 14 feet (22 toes) underwent open hammertoe correction. Time to osseous union (weeks) in the MIS group was 8.76 ± 2.31 weeks with similar outcomes to the open group with union at 8.42 ± 2.31 (p = .65). Return to activity (weeks) was 10.47 ± 3.45 in the MIS group and 9.92 ± 3.03 in the open group with no statistical significance (p = .62). There was 4 recurrent hammertoe deformities in the MIS group (3.23%) with no recurrent hammertoes in the open group (0%). In the MIS group 5 hammertoes had unplanned hardware removal (4.03%) compared to 0 in the open group. There was no statistical significance for both recurrence and unplanned hardware removal (p = 1). Overall, we concluded that both techniques are equivocal with no detectable statistical difference.

Comparative study of K-wire combined with screw vs. K-wire in the treatment of AO type B3.1 phalangeal fractures.

PURPOSE: The purpose of this study was to introduce the surgical method of K-wire combined with screw in the treatment of Arbeitsgemeinschaftfür Osteosynthesefragen (AO) type B3.1 phalangeal fractures and to compare its clinical, radiological and functional outcomes with K-wire fixation. METHODS: This was a retrospective comparative study. From January 2015 to February 2022, we treated 86 patients with AO type B3.1 phalangeal fractures. A total of 71 patients were finally included in the statistical analysis. Thirty-nine patients received K-wires combined with screw, and 32 patients received simple K-wires. The follow-up time was at least 6 months. Outcome measures included general information, operative time, total active motion (TAM), pinch strength, radiological union time, pain assessed by visual analog scale (VAS), Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score, cost, and complications. RESULTS: The follow-up time was 6-12 months, with an average of 7.9 months. All patients achieved clinical and radiological union. Compared with the K-wire fixation group, the TAM, radiological union time and VAS score of the K-wire combined with screw group had obvious advantages. Compared with the opposite healthy hand, the grip strength of the two groups was similar, and there was no significant difference in the QuickDASH score. The incidence rate of complications in the K-wire combined with screw group (2/39) was lower than that in the K-wire fixation group (7/32). CONCLUSIONS: Compared with simple K-wire fixation, K-wire combined with screw in the treatment of AO type B3.1 phalangeal fractures is a safer and reliable surgical method. K-wire controls the rotation and plays a role similar to a "lock". The screw can exert pressure and fix it more firmly. It shortens the time of fracture healing and has a higher TAM and fewer postoperative complications.

K-wire versus screws in the fixation of lateral condyle fracture of humerus in pediatrics: a systematic review and meta-analysis.

BACKGROUND: Lateral condyle fracture of the humerus is the second most common elbow fracture in children. Non-displaced lateral condyle fractures can often be managed with cast and conservative care, while reduction and fixation are often used to treat displaced lateral condyle fractures. Traditionally, K-wire fixation has been used for displaced lateral condyle fractures, but recently fixation using screws has been advocated in some studies. Therefore, we performed a meta-analysis to determine the difference in outcomes and complications between the two different fixation methods for the treatment of displaced lateral condyle fractures of the humerus in pediatric patients. METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used for this review. PubMed, Embase, and Cochrane Library were used for study selection. Studies comparing K-wires and screw fixation in displaced lateral condyle fractures in pediatric patients were included. Clinical outcomes using the Hardacre criteria, infection, limitation of range of motion of the elbow, lateral condyle overgrowth, delayed union, nonunion, and avascular necrosis were compared. Data were analyzed using the meta package in R version 4.2.2, and random-effects or fixed-effects models were used according to heterogeneity. RESULTS: One randomized controlled study and three retrospective cohort studies were included, with a total of 240 patients (K-wire:118, screw:122). The clinical outcome using the Hardacre criteria was not different between the groups (P = 0.54), but the risk of infection (risk ratio [RR] = 5.52, 95% CI: 1.42-21.48, P = 0.01) and limitation of range of motion (RR = 3.75, 95% CI: 1.54-9.18, P < 0.01) were significantly higher in the K-wire fixation group than in screw fixation group. CONCLUSIONS: The use of screws for fixation after reduction in the treatment of lateral condyle fracture of the humerus in children decreases the risk of superficial infection and elbow stiffness compared with the use of K-wire. Although removal of the implant under general anesthesia is necessary, screw fixation can be considered in displaced lateral condyle fractures of the humerus in children. TRIAL REGISTRATION: PROSPERO (CRD42023415643).

Prospective Comparison of the Early Outcomes of Headless Compression Screw and Percutaneous K-Wire Fixation in Metacarpal Fractures.

PURPOSE: The study aimed to assess early clinical outcomes achieved by headless compression screws (HCS) in fixation of metacarpal fractures, and to compare them with outcomes of percutaneous K-wire fixation. The hypothesis was that HCS would show better arc of motion and superior early clinical outcomes. METHODS: This was a randomized study of nonthumb metacarpal neck and shaft fractures. To compare the 2 surgical techniques, 23 patients treated for metacarpal neck and shaft fractures were divided into 2 groups: 11 treated with K-wire fixation and the other 12 with HCS fixation. We followed the patients for 12 weeks. The primary objective was to compare metacarpophalangeal arc of motion, and the secondary aim was to determine clinical union, radiographic union, and recovery time before returning to employment in the 2 groups. RESULTS: At each follow-up visit, patients in the group treated with HCS had better metacarpophalangeal arc of motion than those treated with K-wire fixation. The HCS group showed a shorter time interval to return to work (at 3 weeks) and no complications, while the K-wire group had 1 pin track infection, which was treated with oral antibiotics and pin removal. CONCLUSIONS: Compared with K-wire fixation, limited-open HCS fixation for metacarpal neck and shaft fractures was superior in terms of the early postoperative metacarpophalangeal arc of motion and return to work. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

Clinical and radiological evaluation of radial neck factures in children and adolescents treated by percutaneous leverage reduction with Kirschner wire stabilization.

PURPOSE: The aim of the study was to evaluate the clinical and radiological results of surgical treatment of radial neck fractures in children and adolescents by percutaneous leverage with Kirschner wire stabilization. METHODS: A retrospective clinical and radiographical evaluation was performed on a cohort of 61 patients (mean age 9.7 years; range 3 to 15) with isolated, unilateral radial neck fractures treated between 2009 and 2019. The mean duration of follow-up was 4.2 years (range 2 to 9 years). All fractures were types III and IV according to Judet's classification. RESULTS: After mean follow-up, the radiographic results according to Metaizeau were rated as excellent in 70.5% of respondents, good in 27.9%, satisfactory in 1.6%. According to Mayo Elbow Performance Score, 95.1% of respondents obtained a very good result, 3.3% good, and 1.6% satisfactory. The mean radial neck-shaft angle changed from a mean 51.5° before operation to 3.8° postoperatively (p<0.001). The mean translation was 3.1mm before surgery and 0.5mm postoperatively (p<0.001). No limb axis deviation, elbow joint instability, and infection of the implant insertion site were observed. No statistically significant differences were noted between girls and boys (p>0.05). CONCLUSIONS: Our findings indicate that percutaneous leverage with Kirschner wire stabilization is an effective and safe method for treating isolated radial neck fractures, characterized by a low risk of iatrogenic complications.

Screw placement in arthroscopically assisted osteosynthesis of radial head fractures using a reference k-wire in the radiocapitellar joint: a cadaveric study.

PURPOSE: The optimal screw placement in arthroscopically assisted fixation of radial head fractures is still an issue and no guiding methods have been evaluated in the recent literature. The study hypothesis was that using a "reference k-wire" percutaneously inserted in and parallel to the radiocapitellar joint would enable to achieve a trajectory more parallel to the radial head articular surface as compared to a free-hand k-wire placement. METHODS: Arthroscopically assisted placement of a k-wire in the radial head was performed in seven fresh-frozen human cadaver specimens by three surgeons. Three different techniques were evaluated: freehand drilling (technique A), placement using a "reference" k-wire in the radiocapitellar joint as a reference without (technique B), and with the AO parallel k-wire guide (technique C). Radiographs from all procedures were obtained and the inclination angle "α" between the k-wire and the articular surface of the radial head was measured and compared among the techniques. RESULTS: Angles of 84 radiographs were obtained and showed a mean α angle of 30.1° ± 13° for technique A, 5.7° ± 4.5° for technique B, and 5.4° ± 3.7° for technique C. The angle α was significantly higher with technique A as compared to B (p < 0.0001) and C (p < 0.0001). There was no difference between methods B and C (n.s.). No difference was observed among the surgeons for all three methods (p = 0.66). CONCLUSION: With the use of an additional "reference" k-wire placed in the radiocapitellar joint, the guiding k-wire for screw drilling can be placed almost parallel to the radial head joint line with limited variability and a good reproducibility during arthroscopically assisted radial head fracture fixation. CLINICAL RELEVANCE: The here-presented method of an additional, percutaneous introduced "reference" k-wire is easily applicable and helpful to achieve parallel screw placement during arthroscopically assisted radial head fracture fixation. LEVEL OF EVIDENCE: IV, biomechanical cadaver study.

Comparative Evaluation of the Efficacy of Combined Intramedullary Pinning with K-Wires Pinning in the Treatment of Fifth Metacarpal Neck Fractures versus Conventional Techniques-K-Wires Pinning and Intramedullary Pinning.

Background and Objectives: Since the neck is the weakest part of the metacarpals, the most common metacarpal fracture is a neck fracture, a type which accounts for 38% of all hand fractures. Such fractures can be fixed using a variety of conventional techniques, including intramedullary pinning and K-wire pinning. However, conventional techniques involve complications, such as angulation, stiffness, and rotational deformity. The purpose of this study was to compare the usefulness of our new technique, combined intramedullary pinning with K-wire pinning (IPKP), with those of intramedullary pinning (IP) and K-wire pinning (KP). Materials and Methods: This was a single-center, randomized controlled trial conducted between January 2005 and April 2023. A total of 158 patients with acute displaced fractures of the fifth-metacarpal neck were randomly assigned to either the IPKP group (n = 48), the KP group (n = 60), or the IP group (n = 50). We radiographically evaluated angulation and shortening in three visits: pre-operatively, post-operatively, and at a 1-year follow-up. We clinically evaluated the ranges of motion and Quick-DASH scores to assess daily living performance and the cosmetic scores, using the SBSES score, to assess patients' satisfaction with their cosmetic outcomes. Results: The IPKP group was superior to the KP group and the IP group regarding radiographical and clinical assessments at the 1-year follow-up visit. The angulation was 15.7° (±7.7) in the KP group, 17.0° (±5.9) in the IP group, and 12.6° (±2.5) in the IPKP group (p < 0.001) at the 1-year follow-up visit. The shortening was 0.9 mm (±0.3) in the KP group, 1.4 mm (±0.2) in the IP group, and 0.4 mm (±0.1) in the IPKP group (m < 0.001) at the 1-year follow-up visit. The TAM was 272.6° (±17.5) in the KP group, 271.1° (±18.0) in the IP group, and 274.1° (±14.9) in the IPKP group (p = 0.42). Four patients (6.6%) in the KP group and two patients (4%) in the IP group were reported as having stiffness, while no patients were found to have stiffness in the IPKP group. The average Quick-DASH score was 2.3 (±0.5) in the KP group, 2.5 (±0.4) in the IP group, and 1.9 (±0.4) in the IPKP group (p > 0.05). The average cosmetic score was 3.7 (±1.2) in the KP group, 3.8 (±0.9) in the IP group, and 4.7 (±0.8) in the IPKP group (p < 0.001). A complication involving nonunion occurred in one case (1.6%) in the KP group, while there were three cases (6%) of rotational deformity in the IP groups. Conclusions: With the IPKP technique, accurate reduction can be achieved to improve hand function and cosmetic outcomes.

Treatment of distal radius fractures using a cemented K-wire frame.

BACKGROUND: This retrospective study included an alternative treatment for types A2, A3, and B1 distal radius fractures using percutaneous fixation with a cemented K-wire frame. METHODS: From January 2017 to January 2020, 78 patients with distal radius fractures were treated with percutaneous internal fixation using a cemented K-wire frame. There were 47 male patients and 31 female patients. The fractures were classified into types A2 (n = 10), A3 (n = 46), and B1 (n = 22). X-rays were taken immediately after surgery and after the bone had healed. Wrist function was assessed using the Mayo Wrist Score (90-100, excellent; 80-90, good; 60-80, satisfactory; < 60, poor). Patient satisfaction was assessed using the 10-cm visual analog scale. RESULTS: Neither fixation failure nor K-wire migration was found (P > 0.05). Osteomyelitis was not observed in this series. All patients achieved bone healing after a mean of 4.5 weeks (range, 4 to 8 weeks). Follow-up lasted a mean of 27 months (range, 24 to 33 months). The mean score of wrist function was 97 (range, 91 to 100). Among them, 66 results were excellent and 12 results were good. The mean patient satisfaction was 10 cm (range, 8 to 10 cm). CONCLUSIONS: Percutaneous fixation with cemented K-wire frame is a safe and preferred choice for the treatment of types A2, A3, and B1 distal radius fractures. The frame provides support to prevent wire migration. The fixation technique is a minimally invasive procedure that is easy to perform. LEVEL OF EVIDENCE: Therapeutic study, Level IVa.

Elderly unstable distal radius fractures a prospective cohort study of bone substitutes-augmented percutaneous pinning.

BACKGROUND: Based on debatable recommendations of using bone substitutes for filling of metaphyseal void in elderly unstable distal radius fractures; this study investigated the following question "Do bone substitutes effectively contribute to postoperative stability of k-wire fixation construct and accelerate healing in elderly unstable distal radius fractures?". METHODS: This prospective cohort study was conducted from October 2014 to April 2021. According to use of bone substitutes, 40 patients of elderly unstable distal radius fractures were alternately allocated into; group-(A) of bone substitutes-augmented percutaneous pinning (19 patients); and group-(B) of non-augmented percutaneous pinning (21 patients). Groups were compared for preoperative patients' demographics and postoperative ROM, Quick-DASH and Mayo Wrist scores, radiographic parameters (palmar tilt, radial height and inclination, ulnar variance and intra-articular step-off) and duration until radiographic fracture healing. RESULTS: Statistically, augmented and non-augmented groups were matched in terms of patients' demographics (mean age; 58.7 vs. 62.0 years respectively, P-value = 0.25). All included fractures have healed with insignificantly longer duration in augmented group (7.1 vs. 6.8 weeks, P-value = 0.26). At 12-week postoperative evaluation, radiographic parameters of both groups were comparably well-maintained except for intra-articular step-off which showed significantly less secondary displacement in augmented group (0.1 vs. 0.4 mm, P-value = 0.01). There were insignificant differences in 6-month postoperative ROM, and Quick-DASH and Mayo Wrist scores. CONCLUSION: Compared to its bone substitutes-augmented counterpart; non-augmented percutaneous pinning of elderly unstable distal radius fractures can offer advantages of comparable healing rates and functional and radiographic outcomes, less-invasive approach, shorter operative time and lower cost. LEVEL OF EVIDENCE: III.

Miniplate and K-Wire Fixation for Type Vb Jersey Finger: A Case Series of 9 Patients.

PURPOSE: The aim of this study was to present the results of plate and K-wire fixation for type Vb jersey finger. METHODS: We used a miniplate system combined with a K-wire to treat 9 cases of acute type Vb jersey finger injury. The fracture healing time, functional outcomes, and complications were assessed. RESULTS: The follow-up time ranged from 13 to 44 months. All fractures healed within 7 weeks. The mean active range of motion was 70.6° (60° to 80°) for the distal interphalangeal joint and 105° (100° to 110°) for the proximal interphalangeal joint. All affected fingers were able to move actively with no pain, and there was no nail deformity. Two patients with the longest radiographic follow-up showed a congruent joint surface with no degenerative change at 44 months. CONCLUSIONS: Miniplate and K-wire fixation offers adequate fixation strength for the early initiation of active exercises so that a good functional result can be achieved. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Optimal K-Wire Placement for Indirect Cannulated Screw Fixation of Coronoid Process Fractures: A Radiology-Based Guide.

PURPOSE: Indirect fixation of coronoid process fractures of the ulna, especially arthroscopically, offers the possibility to avoid extensive medial surgical approaches. However, optimal placement of K-wires for cannulated screw fixation is technically challenging. The aim of the present study was to present guide values for K-wire placement for indirect screw fixation of coronoid tip (COT) and anteromedial facet (AMF) fractures of the ulna. METHODS: Computed tomography scans of the elbows of 197 patients with an uninjured ulna were identified and evaluated following a standard measuring protocol. Optimal placement of K-wires was defined as the bisector between the anterior and articular cortex while respecting a 1.6-mm safe zone for each placement. This placement of the K-wires in the COT and the AMF was analyzed by measuring the wire angulation in relation to the posterior ulnar cortex (AUC), the distance from the entry point to the posterior olecranon edge (DPE), and the intraosseous length (IOL). Because the coronoid has a curved shape, measurements of the COT and AMF were expected to differ significantly. Sex was also expected to influence measurements. To determine whether this optimal placement of K-wires can be reliably identified, interobserver and intraobserver reliabilities were evaluated. RESULTS: To address tip fragments, we determined a mean AUC of 64°, DPE of 36 mm, and IOL of 38 mm. Regarding wire placement toward the AMF, the means for the AUC, DPE, and IOL were 79°, 27 mm, and 33 mm, respectively. Statistically significant differences were found between the COT and the AMF for the AUC, DPE, and IOL. Our measuring protocol showed good interobserver and intraobserver reliability. CONCLUSIONS: K-wire placement toward the COT demands a smaller angle, a longer IOL, and a more distal entry point than wires placed toward AMF. These differences reflect the curved and complex anatomy of the coronoid. CLINICAL RELEVANCE: This measuring algorithm can be used to plan osteosynthesis, and the obtained reference values can help understand the coronoid's complex anatomy.

Evaluation of a New Virtual Reality Concept Teaching K-Wire Drilling With Force Feedback Simulated Haptic in Orthopedic Skills Training.

PURPOSE: Surgical simulations are becoming increasingly relevant in musculoskeletal training. They provide the opportunity to develop surgical skills in a controlled environment while reducing the risks for patients. For K-wire internal fixation in musculoskeletal surgery, a force feedback virtual reality (VR) simulator was developed. The aim of this study was to evaluate training results using this technology and compare the results with that of standard teaching on cadavers. METHODS: Twenty participants attending an AO Trauma Course during 2020 were randomly allocated in 2 groups. On day 1, group A was trained by senior surgeons using a cadaver and group B was trained by the VR simulator for K-wire insertion in the distal radius. On day 2, all participants performed K-wire insertion on the cadaver model, without assistance, to validate the training effect. RESULTS: On a surgical skills test, group B performed better than group A. In group B, the entry point of the first K-wire was closer to the targeted styloid process of the radius, and the protrusion of the K-wires into soft tissue was less than that in group A. CONCLUSIONS: Training with the VR simulator for K-wire insertion resulted in better surgical skills than training by a surgeon and cadaver model. CLINICAL RELEVANCE: Training with the VR simulator provides the opportunity to improve and refine surgical skills without the risk of harming patients. It offers easier access, unlimited repetitions, and is more cost-effective compared with training sessions with cadavers.

Comparative evaluation of pinning and cast fixation vs. external fixation after lateral closing-wedge osteotomy for cubitus varus in children.

BACKGROUND: Cubitus varus has been regarded as a poor functional and cosmetic consequence of supracondylar humerus fracture in children. The aim of this study was to assess the clinical and radiologic outcomes of cubitus varus treatments based on fixation methods: Kirschner (K)-wire and cast fixation or external fixation. METHODS: Forty consecutive patients with cubitus varus secondary to supracondylar fractures were retrospectively enrolled between October 2015 and December 2018. Following lateral closing-wedge osteotomy, those undergoing K-wire and cast fixation were included in group A (n = 21) and those who were treated with external fixation comprised group B (n = 19). We measured the bony union, elbow joint range of motion, and carrying angle. The clinical and radiographic results were assessed according to the Bellemore criteria. RESULTS: No significant difference was found between the 2 groups in terms of age, gender, operation duration, union time, and postoperative elbow range of motion (P > .05). A significant difference was noted, however, in postoperative carrying angle and results according to Bellemore criteria in group B (P < .05). No nonunion, myositis ossificans, or neurovascular injury was found at follow-up in the 2 groups. In group A, revision surgery was needed for residual varus in 1 patient and lateral condylar prominence was found in 2 patients. In group B, a superficial pin-site infection occurred in 2 patients, who were treated successfully with oral antibiotics. CONCLUSIONS: Both K-wire and external fixation after lateral closing-wedge osteotomy are reliable and effective for the treatment of cubitus varus in children. Compared with the K-wire method, external fixation achieves better functional and cosmetic results with a shorter learning curve.

Retrospective study of radial dome osteotomy with volar plate fixation versus K-wires in Madelung's deformity: long-term follow-up.

PURPOSE: The emerging role of the locking plate improved the technique also in corrective osteotomies in Madelung's deformity, but there is a lack of analyses between the fixation techniques, as well as little information in functional outcomes and long-term follow-up. The current study compared the outcomes, pitfalls, and advantages of volar plate and screws fixation versus K-wires fixation in a long-term follow-up. METHODS: Twenty-eight children presenting the "distal radius" variant of Madelung's deformity underwent Vickers ligament release and distal radial dome osteotomy between 2009 and 2015. Twenty-three children (20 females and 3 males, mean age 15 years and 7 months at surgery and 24 years and 8 moths at follow-up), with 26 operatively treated wrists, were available for follow-up. A retrospective two-cohort study, evaluating clinically and radiologically results, has been conducted with a mean eight years and seven months follow-up. RESULTS: Bone union and pain relief were obtained in all cases, as well as improvements in wrist motion and radiographic indices. A statistically significant correlation was identified between the volar plate fixation and an improved lunate subsidence on X-ray, and a trend towards an improved DASH score in the cohort with plate and screws, as well as significant improvement in wrist extension and supination always in the plate fixation cohort. CONCLUSIONS: The long-term follow-up enabled the patients to report on more definitive outcomes in terms of functional and cosmetic improvements. Volar plate fixation is an effective technique allowing for simple post-operative management and earlier rehabilitation program with improved clinical and radiographic outcomes.

Phage-Based Control of Methicillin Resistant Staphylococcus aureus in a Galleria mellonella Model of Implant-Associated Infection.

Staphylococcus aureus implant-associated infections are difficult to treat because of the ability of bacteria to form biofilm on medical devices. Here, the efficacy of Sb-1 to control or prevent S. aureus colonization on medical foreign bodies was investigated in a Galleria mellonella larval infection model. For colonization control assays, sterile K-wires were implanted into larva prolegs. After 2 days, larvae were infected with methicillin-resistant S. aureus ATCC 43300 and incubated at 37 °C for a further 2 days, when treatments with either daptomycin (4 mg/kg), Sb-1 (107 PFUs) or a combination of them (3 x/day) were started. For biofilm prevention assays, larvae were pre-treated with either vancomycin (10 mg/kg) or Sb-1 (107 PFUs) before the S. aureus infection. In both experimental settings, K-wires were explanted for colony counting two days after treatment. In comparison to the untreated control, more than a 4 log10 CFU and 1 log10 CFU reduction was observed on K-wires recovered from larvae treated with the Sb-1/daptomycin combination and with their singular administration, respectively. Moreover, pre-infection treatment with Sb-1 was found to prevent K-wire colonization, similarly to vancomycin. Taken together, the obtained results demonstrated the strong potential of the Sb-1 antibiotic combinatory administration or the Sb-1 pretreatment to control or prevent S. aureus-associated implant infections.