Neglected Dorsal Proximal Interphalangeal Joint Dislocation Treated by Volar Plate Arthroplasty: A Case Series.

Chronic unreduced dislocations of the proximal interphalangeal joint are uncommon, and management principles for these injuries have not been defined. The dislocation can be volar or dorsal and closed reduction is rarely successful owing to soft tissue contractures. Treatment options in literature reviews for such rare injuries included open reduction of pip joint with volar plate arthroplasty, extension block pinning, hemi hamate arthroplasty, pip joint arthrodesis, Suzuki dynamic frame fixation, open reduction and repair of capsule and collateral ligaments with suture anchors. Few cases of amputation following treatment were even reported in literature emphasizing the role of meticulous soft tissue handling in such neglected cases of hand. We report six cases of neglected (more than three months old) dorsal dislocation of the PIP joint of the hand, treated with volar plate arthroplasty and extension block pinning. A functional range of motion with a stable joint can be achieved in such injuries with volar plate arthroplasty, as long as the articular cartilage is relatively preserved and bone loss is <30%.

Bony Mallet Thumb Treated With the Ishiguro Extension Block Technique: A Case Report.

A bony mallet thumb is an extremely rare injury. An 82-year-old man fell from a standing height and injured his right thumb. Imaging examinations revealed a rare intra-articular fracture at the dorsal side of the base of the distal phalanx of the thumb called the bony mallet thumb. Conservative treatment was adopted initially; however, surgery was deemed necessary because of the redislocation of the bone fragment. Thus, the Ishiguro extension block technique was used, and three months later, satisfactory thumb function was achieved. The Ishiguro technique is a relatively simple procedure often performed for bony mallet fingers. The current case indicated that it can also be used to treat cases of bony mallet thumbs successfully.

Extension block pinning for chronic volar base fractures of the middle phalanges.

Due to the simplicity, low cost and benefit of avoiding long-term joint immobilization, extension block pinning could be a suitable option for treating the volar base fractures of the middle phalanges. The aim of the present study was to evaluate the outcomes of using extension block pinning in chronic volar base fractures of the middle phalanges. In total, 26 patients with chronic closed volar base fractures of the middle phalanges were included our study. The mean age was 37 years (SD 11.59), and the mean follow-up time was 35 months (SD 19.41). The mean active range of motion (ROM) after surgery was 93° (SD 12.9). There was a negative correlation between the age and the ROM of the injured proximal interphalangeal joint after surgery. ROM did not correlate with the articular surface involvement or the interval between injury and surgery. We obtained a satisfactory result from extension block pinning for volar base fractures of the proximal interphalangeal joint in patients with chronic injuries.Level of evidence: IV.

Mallet Hallux Injury Fixed With Extension Blocking Pin Technique: A Case Report.

Mallet hallux injuries are relatively rare, and management can range from conservative treatment to surgical fixation. Only a few cases of surgically treated are reported, and there is no consensus on the superiority of one technique to others in surgical treatment. We reviewed various options for surgical fixation of Mallet hallux injury and presented a case of mallet hallux injury treated with Kirschner wires with an extension blocking technique.Level of Evidence: V.

Speech Perception Improvement Algorithm Based on a Dual-Path Long Short-Term Memory Network.

Current deep learning-based speech enhancement methods focus on enhancing the time-frequency representation of the signal. However, conventional methods can lead to speech damage due to resolution mismatch problems that emphasize only specific information in the time or frequency domain. To address these challenges, this paper introduces a speech enhancement model designed with a dual-path structure that identifies key speech characteristics in both the time and time-frequency domains. Specifically, the time path aims to model semantic features hidden in the waveform, while the time-frequency path attempts to compensate for the spectral details via a spectral extension block. These two paths enhance temporal and spectral features via mask functions modeled as LSTM, respectively, offering a comprehensive approach to speech enhancement. Experimental results show that the proposed dual-path LSTM network consistently outperforms conventional single-domain speech enhancement methods in terms of speech quality and intelligibility.

Long-term outcomes after extension block pinning for fracture-dislocations of the proximal interphalangeal joint.

LEVEL OF EVIDENCE: IV.

Comparison of extension block pinning technique versus pin orthosis-extension block pinning technique for acute mallet fractures: a prospective randomized clinical trial.

INTRODUCTION: The extension block pinning technique (EBPT) is a popular surgical treatment for mallet fractures; however, it has several drawbacks. The purpose of this randomized clinical trial was to compare EBPT to the pin orthosis-extension block pinning method (PO-EBPT) in the treatment of mallet fractures involving more than one-third of the joint surface but without primary joint dislocation. MATERIALS AND METHODS: Sixty-five patients with mallet fractures were randomized into two groups between June 2017 and January 2020: Group I (33 patients) was treated with EBPT and group II (32 patients) was treated with PO-EBPT. Five patients were lost to follow up due to lack of follow-up and death. There were no significant differences in the clinical and demographic characteristics of both groups. Patients were evaluated according to fracture union, extension lag, distal interphalangeal (DIP) joint range of motion, Crawford's criteria, and complication rates. The patients were followed-up post-operatively at 2 weeks, 6 weeks, 3 months, 6 months, 1 year, and annually thereafter. RESULTS: A total of 60 patients were randomized into two groups: one (30 patients) was treated with EBPT and the second (30 patients) with PO-EBPT. There were no significant differences between the two groups in terms of fracture union and active DIP joint flexion (P = 0.743 and P = 0.059, respectively). The mean extension lag of the DIP joint in the EBPT group was significantly greater than the PO-EBPT group (10° ± 9.47° vs. 4.17° ± 7.2°, P = 0.009). According to the Crawford criteria, the PO-EBPT group showed significantly better outcomes (P = 0.005). The complication rates were similar between groups (P = 0.45). CONCLUSION: In comparison to the EBPT technique, the group of patients operated with PO-EBPT had superior clinical outcomes and less loss of extension at the DIP joint according to the Crawford's criteria.

Comparison of interfragmentary pinning versus the extension block technique for acute Doyle type 4c mallet finger.

The aim of this study was to compare the closed reduction interfragmentary pinning method (IPM) with the extension block technique (EBT) for bony mallet finger. Patients who underwent mallet finger operations were screened retrospectively for the following inclusion criteria: Doyle type 4c, age between 18 and 75 years, less than 4 weeks to surgery, and more than 1 year of follow-up time. Group I underwent a closed reduction IPM, and group II underwent the EBT. Lateral radiographs taken during the preoperative and final examination were used to evaluate the size and amount of displacement from the distal interphalangeal (DIP) joint and the dorsal fragment as well as the articular surface. Operation times were compiled from patient records. During the final examination, pain and DIP joint range of motion (ROM) were assessed and complications were recorded. The Crawford criteria were used for functional results. Fifteen patients in group I (8 men, 7 women) and 17 patients in group II (10 men, 7 women) were evaluated. Age, gender, time to surgery and follow-up time showed no statistically significant differences between the two groups. The differences in fragment size, preoperative and postoperative joint displacement, amount of dorsal displacement and DIP joint ROM were not statistically significant between the two groups. However, the operation time was significantly shorter time in group I than in group II (p=0.000). The average time to fracture union was significantly longer in group I (7.3 weeks) than in group II (6 weeks) (p=0.013). The EBT has faster time to union and is a safer method with lesser risk of arthritis and fragmentation. The IPM can be an alternative with shorter operation time, less pin bed infection and nail bed damage, especially in Doyle type 4c cases with large fragments.

Mini-Open Reduction and Extension Block Pinning for Irreducible Mallet Fractures: A Minimally Invasive Technique for Anatomical Reduction.

Background: Dorsal rotation or persistent displacement of the fracture fragment is frequently encountered in extension block pinning for mallet fractures. We reviewed nine irreducible mallet fracture patients treated with mini-open reduction and extension block pinning. Methods: A small V-shaped incision was made on the fracture gap when there was persistent displacement of fracture fragment despite closed maneuvers and percutaneous procedures while performing extension block pinning. Soft tissue or granulation tissue hampering reduction was removed through the incision. Anatomical reduction was guided with a freer elevator. The incision was closed by distal interphalangeal joint transfixation in extension without any suture. Pin tips were buried under the skin. The incision and pin entry sites were covered with skin adhesive, and the patients were allowed to wash their hands 1-2 days after the surgery. No splint was applied postoperatively. Mean follow-up period was 13 months. Results: Anatomical reduction was achieved in 7 out of 9 patients. In the rest 2 patients, postoperative step-off of the articular surface at the fracture site was less than 0.5 mm. Solid union was achieved in all cases. The mean extension lag at final follow-up was 0°. No patient developed postoperative external bleeding or other complications in the incision site or the pin site. Conclusions: Mini-open reduction and extension block pinning appears to be a good option for irreducible mallet fractures, which improves reduction quality and patients' convenience.

A Novel Hook Wire Tension Technique for the Treatment of Mallet Fractures: A Comparison with the Extension Block Pinning Technique.

We developed a percutaneous surgical technique that allows early mobilization and compression for the treatment of mallet fractures. The aim of this study was to describe this novel technique called the hook wire tension technique (HWTT) and provide a clinical and radiological comparison between HWTT and the extension block pinning technique (EBT) in the treatment of mallet fractures. This retrospective study included 23 mallet fracture patients treated using HWTT and 25 patients treated using EBT. At the final follow-up visit, extension lag and flexion of the distal interphalangeal joint (DIPJ) were measured. DIPJ pain was assessed by the visual analogue scale (VAS) score, and the overall clinical outcomes were graded according to the Crawford criteria. Time to bone healing and osteoarthritis development were assessed radiologically. Complications, including skin necrosis, dorsal prominence and nail deformity, were also compared. The mean follow-up period was 18 months (range: 12-24) in the HWTT group and 19.2 months (range: 12-26) in the EBT group (p = 0.239). There was no statistically significant difference between the two groups in terms of mean extension lag of the DIPJ, mean VAS scores and mean time to bone healing (p > 0.405). The mean DIPJ flexion was greater in the HWTT group compared with the EBT group (p = 0.001). According to the Crawford criteria, outcomes were similar in both groups (p = 0.370). No statistically significant difference was found between the two groups when each complication was compared (p > 0.358). The short-term clinical and functional results of HWTT were found to be similar to those of EBT in the surgical treatment of mallet fractures.

Mallet Fractures with Long Fragment Had Poor Outcomes on Extension Block Pinning.

Background: Although extension block pinning for mallet fracture is popular, it occasionally results in poor outcome. We reviewed previous cases to elucidate the factors associated with poor outcome. Methods: From 2012 to 2017, 50 mallet fingers in 50 patients were consecutively repaired by extension block pinning using modified Ishiguro method. Inserted Kirschner-wires (K-wires) were removed at 6 weeks, followed by night splinting in extension. For outcome evaluation, distal interphalangeal (DIP) joint motion was measured and classified as either good or poor. Poor outcome was defined as either > 10° of extension lag or < 40° of active flexion or the presence of DIP joint pain. Associations between outcome and age, affected finger, interval to operation, fragment size (in terms of joint surface and dorsal cortex ratios), and fixation angle were evaluated. Results: 33 fingers (66%) had good outcome and 17 (34%) had poor outcome. Mean age was significantly greater in the poor (50.6 years) than in the good (40.1 years) outcome group (p < 0.05). The dorsal cortex ratio was also significantly larger in the poor than in the good outcome group (p = 0.006), but there was no significant difference between two groups in joint surface ratio. Affected finger, interval to surgery, and fixation angle also did not significantly differ between groups. Conclusions: Fracture fragments with a long dorsal cortex and older age associated with poor outcome following extension block pinning for mallet finger. The dorsal cortex ratio should be evaluated pre-operatively to determine the appropriate treatment method.

Splinting versus extension-block pinning of bony mallet finger: a randomized clinical trial.

Surgical treatment of bony mallet fingers is frequently recommended, but the evidence is sparse. This randomized clinical trial aimed to compare nonoperative splinting versus extension-block pinning of bony mallet fingers with involvement of more than one-third of the joint surface but without primary joint subluxation. Thirty-two patients were randomized and 28 fulfilled the protocol. At 6 months follow-up, there were no significant differences in active extension lag in the distal interphalangeal joint (the primary outcome) or in patient-reported function and pain scores. Flexion and active range of motion in the distal interphalangeal joint and finger-to-palm distance were better in the splinting group, but three patients developed secondary subluxation. We conclude from this study, that splinting these injuries is safe and efficient in restoring joint motion, but splinting does not sufficiently prevent secondary subluxation of the joint. Radiographic follow-up during splinting appears to be necessary. Level of evidence: I.

Mallet finger - A modified technique using the finger nail as a fixation point for the temporary immobilization of the distal interphalangeal joint - A biomechanical study.

BACKGROUND: The aim of the current biomechanical study was to investigate a newly developed surgical technique for mallet fingers. The new method is based on the Ishiguro method which requires a K-wire through the distal interphalangeal joint for temporary fixation. The new technique avoids the joint trans fixation using a specially designed finger nail holder. This method was compared to the established Ishiguro's technique. METHODS: For biomechanical testing, 32 paired, fresh-frozen human fingers (Digit II-V) of 4 donors (ages 60 to 71 years) were used. The paired fingers were assigned to either the new method or Ishiguro's technique. The biomechanical testing consisted of a cyclic cantilever bending (2000 cycles, 1-7N) followed by a load to failure test. The groups were evaluated for plastic deformation, stiffness, change in stiffness during cyclic loading, subluxation and failure load by analysing force-deflect data and fluoroscopic images. FINDINGS: The nail fixation group showed significantly higher failure loads and stiffness than the trans fixation group. The values of plastic deformation were significantly lower in the nail fixation group. No differences were found in the change of stiffness. No subluxation was found in both groups. INTERPRETATION: In the current biomechanical study, nail fixation performed at least as good as Ishiguro's trans fixation technique. The results and ease of implementation indicate that the newly developed nail fixation technique might be a useful treatment method in daily clinical practice without the need of temporary joint trans-fixation avoiding possible associated problems. To establish this method, clinical trials will be necessary.

Modified Transosseous Wiring Technique for Neglected Fracture-Dislocation of the Proximal Interphalangeal Joint.

BACKGROUND: Fracture-dislocation of the proximal interphalangeal (PIP) joint of the finger is challenging due to the high risk of stiffness. The purpose of this study is to evaluate the clinical and radiological results of a modified transosseous wiring technique for the management of chronic fracture-dislocations of the PIP joint. METHODS: Ten patients (nine men and one woman; mean age, 38.3 years; range, 21 to 69 years) with neglected fracture-dislocation of the PIP joint were included. The mean duration from injury to operation was 14.7 weeks (range, 3 to 66 weeks). The dorsolateral approach and extension block pinning were used to reduce dislocation. After thorough debridement of the scar tissues in the dorsal dead space and the fracture site, the reduction was maintained with transosseous wiring. Radiologic evaluations of bone union and arthritic changes and clinical evaluations (range of motion of the PIP joint and Disabilities of the Arm, Shoulder and Hand [DASH] score) were performed. The mean follow-up period was 12.9 months (range, 12 to 19 months). RESULTS: All patients demonstrated evidence of radiographic healing within a mean healing time of 6 weeks (range, 4 to 10 weeks); however, one had a widened gap and one had an early arthritic change. The mean range of motion in the PIP joint was 81° (range, 50° to 105°). The mean DASH score was 21.6 (range, 7.5 to 35.8). CONCLUSIONS: For chronic fracture-dislocation of the PIP joint, transosseous wiring with direct curettage and optimal bone purchase can provide satisfying outcome.

Mallet Finger Fracture Treated with Delta Wiring Technique: A Case Report of a New Fixation Technique.

INTRODUCTION: Extension-block pinning is a popular surgical treatment method for mallet fractures but is associated with several pitfalls. Transfixation Kirschner wires used in the extension-block pinning technique may cause iatrogenic nail bed injury, bone fragment rotation, chondral damage, or osteoarthritis. The objective of this study was to determine the result of the delta wiring technique in a case of mallet finger with fracture fragment involving more than one-third of the distal phalanx articular surface. This is the first reported case of mallet fracture treated with delta wiring in literature. CASE REPORT: A 30-year-old male patient admitted in our institute with complaints of severe pain in the right index finger with inability to extend the distal interphalangeal joint (DIP) for 5 days. There was a history of fall from the bike before this complaint. Radiographs revealed a bony mallet fracture involving more than one-third of the articular surface of distal phalanx. The patient was taken up for delta wiring fixation of the fracture. Radiographic bony union was seen at 7 weeks. At the final follow-up at 1 year, DIP had 75° of flexion and had extension deficit of 5°. According to Crawford's criteria, the patient had good results with a VAS score of 1 with no pain. CONCLUSION: Delta wiring technique is a new and safe treatment modality for bony mallet fracture with fracture fragment involving more than one-third of the distal phalanx articular surface as satisfactory clinical and radiological outcomes obtained in our case.

Supplemental Method for Reduction of Irreducible Mallet Finger Fractures by the 2-Extension Block Technique: The Dorsal Counterforce Technique.

PURPOSE: We suggest a method to achieve anatomical reduction in mallet finger fractures that are insufficiently treated by the 2-extension block wire technique. METHODS: We performed a retrospective review of 18 patients who were found to have an irreducible dorsal fragment and distal interphalangeal joint incongruence owing to rotation of the dorsal fragment in the sagittal plane. In these cases, we additionally employed a dorsal counterforce technique to supplement the 2-extension block technique. An additional K-wire was used to apply counterforce against the distal part of the dorsal fragment and control rotation in the sagittal plane. RESULTS: All 18 fractures united. Congruent joint surfaces and anatomical reduction were seen in all cases. The mean active flexion of the distal interphalangeal joints was 83.8° (range, 79°-88°) and the mean extension loss was 0.4° (range, 0°-4°). CONCLUSIONS: We believe that the dorsal counterforce technique effectively supplements the 2-extension block K-wire technique and aids control of dorsal fragment rotation in the sagittal plane. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Modified Transosseous Wiring Technique for Neglected Fracture–Dislocation of the Proximal Interphalangeal Joint

BACKGROUND: Fracture–dislocation of the proximal interphalangeal (PIP) joint of the finger is challenging due to the high risk of stiffness. The purpose of this study is to evaluate the clinical and radiological results of a modified transosseous wiring technique for the management of chronic fracture–dislocations of the PIP joint. METHODS: Ten patients (nine men and one woman; mean age, 38.3 years; range, 21 to 69 years) with neglected fracture–dislocation of the PIP joint were included. The mean duration from injury to operation was 14.7 weeks (range, 3 to 66 weeks). The dorsolateral approach and extension block pinning were used to reduce dislocation. After thorough debridement of the scar tissues in the dorsal dead space and the fracture site, the reduction was maintained with transosseous wiring. Radiologic evaluations of bone union and arthritic changes and clinical evaluations (range of motion of the PIP joint and Disabilities of the Arm, Shoulder and Hand [DASH] score) were performed. The mean follow-up period was 12.9 months (range, 12 to 19 months). RESULTS: All patients demonstrated evidence of radiographic healing within a mean healing time of 6 weeks (range, 4 to 10 weeks); however, one had a widened gap and one had an early arthritic change. The mean range of motion in the PIP joint was 81° (range, 50° to 105°). The mean DASH score was 21.6 (range, 7.5 to 35.8). CONCLUSIONS: For chronic fracture–dislocation of the PIP joint, transosseous wiring with direct curettage and optimal bone purchase can provide satisfying outcome.

A retrospective study of closed extension block pinning for mallet fractures: Analysis of predictors of postoperative range of motion.

BACKGROUND: Extension block pinning is a simple and reliable technique for mallet fractures, but poor results are sometimes obtained. The predictors of postoperative range of motion after extension block pinning of mallet fingers were investigated. METHODS: The outcomes for postoperative active motion of the distal interphalangeal (DIP) joint, such as flexion angle, extension loss, and total range of motion, were examined. Predictors such as age, gender, finger, fragment size, joint subluxation, the time from injury to operation, procedure, fixation angle, the time from operation to wire removal, and joint step-off were evaluated statistically. RESULTS: With a mean 12.2-month follow-up, according to Crawford's criteria, 49 of 116 fingers (42%) had an excellent result, 37 (32%) had a good result, 29 (25%) had a fair result, and 1 (1%) had a poor result. The mean flexion angle was 62.9 ± 13.2°, extension loss was -6.6 ± 7.3°, and total range of motion was 55.8 ± 17.0° in the DIP joint. Pin tract infections were confirmed in 7 fingers with poor results. There were no complaints about nail deformity or skin abnormality. On multivariate analysis, significant predictors of poor postoperative motion were increased age chronic case, remained joint step-off, excess flexed fixation angle, and long-term wire placement. CONCLUSIONS: Extremely flexed fixation and chronic case easily causes extension loss in the DIP joint. In closed extension block pinning, joint fixation with an extreme flexion angle should be avoided and the pinning wire should be removed as soon as possible after confirming bony union.

Outcomes Following Operative Treatment of Adolescent Mallet Fractures.

BACKGROUND: Many surgeons advocate for surgical intervention of adult mallet fractures that involve either subluxation of the distal interphalangeal (DIP) joint or those that involve more than one-third of the articular surface. However, the efficacy of operative treatment and complication rates are unclear regarding the adolescent population. QUESTIONS/PURPOSES: The goal of this study is to evaluate the clinical outcomes following operative fixation of bony mallet fractures in the adolescent population. METHODS: Seventeen patients with bony mallet fractures treated surgically were retrospectively reviewed. Twelve patients were treated by closed reduction with extension block pinning. The other patients underwent an open reduction and pin fixation. The average age was 15.2 years (13-18). Most injuries were sport related. The average time from injury to presentation was 17 days and from injury to surgery was 24.5 days. Nine patients had subluxation at the DIP joint and all involved at least one-third of the articular surface. RESULTS: The average time from surgery to pin removal was 28 days (19-46). All distal phalanx physis were closed or nearly closed. One patient reported pain at the final follow-up. Two patients (11.8%) had major complications. One had an extension contracture postoperatively, did not attend therapy, and re-fractured 5 months later requiring reoperation. The second was treated delayed (32 days) and lost fixation, requiring revision surgery and antibiotics for a superficial infection. Two patients with delayed treatment (32 and 44 days) had an extensor lag (11.8%). CONCLUSIONS: Operative treatment of mallet fractures with subluxation or involving more than one-third of the articular surface appears effective. Pin removal 4 weeks postoperatively appears adequate. Complications occurred with delayed presentation and non-compliance.

Correlation between extension-block K-wire insertion angle and postoperative extension loss in mallet finger fracture.

INTRODUCTION: Extension-block pinning represents a simple and reliable surgical technique. Although this procedure is commonly performed successfully, some patients develop postoperative extension loss. To date, the relationship between extension-block Kirschner wire (K-wire) insertion angle and postoperative extension loss in mallet finger fracture remains unclear. HYPOTHESIS: We aimed to clarify this relationship and further evaluate how various operative and non-operative factors affect postoperative extension loss after extension-block pinning for mallet finger fracture. MATERIALS AND METHOD: A retrospective study was conducted to investigate a relationship between extension block K-wire insertion angle and postoperative extension loss. The inclusion criteria were: (1) a dorsal intra-articular fracture fragment involving 30% of the base of the distal phalanx with or without volar subluxation of the distal phalanx; and (2) <3 weeks delay from the injury without treatment. Extension-block K-wire insertion angle and fixation angle of the distal interphalangeal (DIP) joint were assessed using lateral radiograph at immediate postoperative time. Postoperative extension loss was assessed by using lateral radiograph at latest follow-up. Extension-block K-wire insertion angle was defined as the acute angle between extension block K-wire and longitudinal axis of middle phalangeal head. DIP joint fixation angle was defined as the acute angle between the distal phalanx and middle phalanx longitudinal axes. RESULTS: Seventy-five patients were included. The correlation analysis revealed that extension-block K-wire insertion angle had a negative correlation with postoperative extension loss, whereas fracture size and time to operation had a positive correlation (correlation coefficient for extension block K-wire angle: -0.66, facture size: +0.67, time to operation: +0.60). When stratifying patients in terms of negative and positive fixation angle of the DIP joint, the independent t-test showed that mean postoperative extension loss is -3.67° and +4.54° (DIP joint fixation angles of <0° and ≥0°, respectively, P=0.024). When stratifying patients in terms of extension-block K-wire insertion angle (30°, 30°-40°, >40°), ANOVA showed significantly less postoperative extension loss for higher insertion angles (>40°) than for medium insertion angles (30°-40°). Mean postoperative extension loss difference between higher insertion angle (>40°) and medium insertion angle (30°-40°) was 11° (P=0.002). DISCUSSION: Using an insertion angle of the extension-block K-wire of 40°-45° and a slightly hyperextended position of the DIP joint may help reducing postoperative extension loss. LEVEL OF EVIDENCE: Therapeutic level III.