Outcomes of Mini-Invasive Arthroscopic Arthrolysis Combined with Locking Screw and/or Intramedullary Nail Extraction after Osteosynthesis of the Proximal Humerus Fracture

Data on the effectiveness of arthroscopic arthrolysis and extraction of osteosynthetic material after osteosynthesis of the proximal humerus in patients with persisting problems are rare and insufficient. In this study, we performed arthroscopic arthrolysis and extraction of fixation screws, and, where protruding, extraction of the nail in 34 patients with problems persisting 12 months after osteosynthesis of the proximal humerus using an intramedullary nail. The effectiveness of the treatment was assessed using the Constant–Murley shoulder score and forward flexion difference between the treated arm and the contralateral one. A median increase of 16 points in CMS score and 30 degrees reduction in the arm forward flexion difference was recorded 12 months after the arthroscopy. The improvement was significantly higher in the patient group with intramedullary nail extraction (however, this group had worse pre-operative values and the screw was only extracted where likely to cause problems). The median time to heal was 11 weeks; no serious peri- or post-procedural complications occurred. Mini-invasive arthroscopic arthrolysis combined with extraction of osteosynthetic material proved to be a safe and effective method for treatment of patients after osteosynthesis of the proximal humerus using an intramedullary nail with persisting pain and/or mobility limitation.

Screw stripping and its prevention in the hexagonal socket of 3.5-mm titanium locking screws

There have been several reports about the difficulties in removing 3.5-mm titanium locking screws from plates due to the stripping or rounding of the hexagonal screw socket. We investigated whether stripping the locking screw sockets can be prevented by using different screwdrivers or interposing materials into the socket during removal. We overtightened 120 3.5-mm titanium locking screws (Depuy Synthes, Paoli, PA) equally into locking plates on sawbone tibia models, applying a uniform torque of 4.5 Nm, exceeding the recommended torque of 1.5 Nm. Twenty screws each were removed using a straight-handle 2.5-mm screwdriver, T-handle screwdriver, hex key wrench, and straight-handle screwdriver with a non-dominant hand. In addition, 20 screws were removed using foil from a suture packet inserted into the screw socket or using parts of a latex glove inserted into the screw socket. The incidence rates of screw stripping using the straight-handle screwdriver, T-handle screwdriver, hex key wrench, non-dominant hand, foil interposition, and latex glove interposition were 75%, 40%, 35%, 90%, 60%, and 70%, respectively. When a T-handle screwdriver or hex key wrench was used, the probability of screw stripping was 4.50 times (odds ratio = 4.50, 95% confidence interval = 1.17 to 17.37, p = 0.03) and 5.57 times (odds ratio = 5.57, 95% confidence interval = 1.42 to 21.56, p = 0.01) lower than that with the straight-handle screwdriver, respectively. Foil or latex glove interpositions did not prevent screw stripping. Thus, in the current experimental study, T-handle screwdriver or hex key wrench usage decreased the incidence rate of screw stripping during removal compared to straight-handle screwdriver use.

An Uncommon Complication of Arteriovenous Fistula Following Intramedullary Nail Distal Locking – A Case Report

Introduction:An arterial pseudo aneurysm formation is an unusual complication following intramedullary nail distal locking screw insertion. During such surgical procedure, arterial laceration might damage the wall, allowing blood leakage into the soft- tissue surrounding. Only few records are available regarding such injuries. Case Report: A 19-year-old male diagnosed with femoral shaft fracture after a trauma event, was treated using Antegrade Long Intra-Medullary Nail with distal locking screw. Following post-operative serial blood count indicating a consistent decrease in his Haemoglobin levels, a Computed Tomography angiogram was performed and showed an arteriovenous fistula of the lateral superior geniculate artery. The artery was coiled, and haemoglobin levels were stabilized again. Conclusion: A distal interlocking screw should be carefully placed, including blunt dissection before the drilling and screw placement. In addition, blood counts were proved essential in routine. Keywords: Arteriovenous fistula, intramedullary nail distal locking, antegrade long intra-medullary nail.

First metatarsal elevation after subtalar arthroeresis in children with flatfeet

BACKGROUND: Arthroereisis of the subtalar joint is a common surgical option for children with flat feet. Along with all the advantages of arthroereisis of the subtalar joint, the indications for surgery, the optimal age for surgical treatment, as well as secondary deformities of the forefoot that occur after treatment are debatable. AIM: The aim of this study was to analyze the frequency and degree of I metatarsal elevation after arthroereisis of the subtalar joint in children. MATERIALS AND METHODS: The study group included 106 patients / 202 feet who were treated at the H. Turner Pediatric Orthopedic Institute for the period from 2015 to 2019. The average age was 11 years (8; 13). Arthroereisis of the subtalar joint was performed in two variants: arthroereisis with a locking screw in the calcaneus 44 patients / 83 feet and arthroereisis with a locking screw in the talus 62 patients / 119 feet. An analysis was made of the incidence of I metatarsal elevation after arthroereisis of the subtalar joint. The relationship between the degree of elevation of the first metatarsal bone and the main clinical and radiological characteristics of the feet at different times after surgical treatment was analyzed. RESULTS: The frequency of elevation of the I metatarsal bone with the use of a calcaneal locking screw was 20.7%, and with the use of a talar locking screw, the frequency is 51.6%. Clinical manifestations of elevation of the I metatarsal bone took place when the amount of elevation was more than 65% of the size of the head of the I metatarsal bone. At a period of 23 years after the operation, elevation of the I metatarsal bone were noted in 15.9%. A statistically significant correlation (Spearman coefficient) was noted between the degree of elevation of the I metatarsal bone and the following parameters: anteroposterior Meary angle (0.360), lateral Kite angle (0.367), lateral Meary angle (0.378), foot arch angle (0.344), tibio-talar angle (0.351), Friedlands index (0.402). CONCLUSIONS: Incidence of the first metatarsal bone elevation reaches 51% of the in patients in the immediate follow-up period after performing arthroereisis of the subtalar joint. Elevation of the first metatarsal bone developed dorsal bunion with an elevation value of more than 65%. The degree of elevation of the first metatarsal bone has a positive correlation with the degree of planovalgus deformity correction. Elevation of the first metatarsal bone tends to decrease up to 15% in the long-term follow-up after surgical treatment.

Case Study: Consecutive Failure of Lube Oil Cooler Fans Coupling

Do we analyze on why can even the most reliable turbomachinery are getting failure and stopped? In some cases, it's all about bad installation or design literally. This paper explores the challenges one site had with repeated failure of lube oil fin fan coolers coupling which caused the unit availability of more than 3 months. It outlines the troubleshooting attempts made to remedy this issue, its root cause, and the resulting solution. This issue occurred at a site with a train configuration of motor driven centrifugal compressors. The plant lube oil system has been configured with 3 trains. Each train has been configured with Main electric motor + Vorecon Gearbox + Low Pressure centrifugal compressor + High Pressure centrifugal compressor. Lube oil system of the train has been configured as 2 lube oil coolers and 2 working oil coolers. Lube oil coolers are having fins with air cooler type. Air is supplied by fin fans and each train has 2 lube oil cooler fans and 2 working oil cooler fans. In total site has 3 trains x 4 fin fans so it has 12 fin fan cooler fans. All cooler fans are driven by electric motor which is coupled with gearbox and gear box is connected with cooler fan. During normal operation of working oil cooler fan A- stopped rotation suddenly from normal operation. During investigation, motor shaft was found running freely. No movement was seen on cooler fan. Coupling between motor to gearbox was inspected. Coupling is shear plate coupling. Its spacer flexible element were found broken into several pieces. Further investigation revealed that motor coupling hub was moving free axially back and forth due to clearance between motor shaft to coupling hub internal diameter. Motor side Coupling hub bolt hole was found with loss of material and ovality in shape. Hub locking Allen screw was found in damaged condition. Missing materials were noted and broken shear plate materials were found around coupling guard area. While site team was conducting the investigation on the unit A, similar incident occurred in next unit and other 3 units with 2 days difference between them. During detailed investigation it has been noted that all motor to gear box coupling are shear plates and shear plates were broken. Coupling hub was found loose and coupling hub locking screw was found broken or partial damage.

A Finite Element Analysis and Cyclic Load Experiment on an Additional Transcortical-Type Hole Formed Around The Proximal Femoral Nail System’s Distal Locking Screw

Background A complication associated with the distal locking screw used in the proximal femoral nail (PFN) system is the formation of accidental additional holes. We hypothesized that an increase in stress around additional holes is a relevant factor contributing to fractures. This study aimed to evaluate stress changes in the cortical bone around additional screw holes using finite element analysis. Methods Proximal femoral nail PFN antirotation (PFNA)-II (Synthes, Solothurn, Switzerland) was inserted into a femur model. An additional 4.9-mm transcortical hole was made either anteriorly (anterior hole model) or posteriorly (posterior hole model) to the distal locking screw. Finite element analysis was used to calculate compression, tension, and load limits to investigate stress around additional holes with respect to the direction of screw penetration and degree of osteoporosis. The results were then compared with those of mechanical testing. A 31A-21 type intertrochanteric fracture was applied. As a control group, a model without additional holes (no-hole model) was developed. Repeated load-loading tests were performed on 10 model bones per model group. Results Tensile stress was significantly greater in the no-hole model when additional screw holes were present, and the anterior hole showed a higher maximum stress value than the posterior hole did, suggesting that the anterior hole was more susceptible to fracture. The change in tensile stress first appeared in the hole around the lateral cortical bone and proceeded to the medial side. Biomechanical testing showed that fractures around the distal locking screw occurred in 0 cases of the no-hole, 10 of anterior hole, and 9 of the posterior hole models. Conclusions During PFN surgery for intertrochanteric fracture, holes with distal locking screws fixed and removed at the anterior and posterior of the nail can be a risk factor for fractures in the surrounding area.

Treatment of fractures of the proximal end and humeral shaft by locked intramedullary nailing in adults: Case series and literature review

Introduction: Intramedullary nailing is a good indication for stabilizing displaced fractures of the proximal end and shaft of the humerus in adults. Methods: This was a prospective series of 24 patient, over a period of 9 months. The aim of this study is to report the epidemiological and clinical aspects of patients treated with a locked humeral nail and to show the medium-term interest, of this therapeutic method, thus discussing the complications. Results: All patients had received intramedullary nailing of the humerus. The average age was 77.08 years. The female sex was more represented with 66.66% and the right side was frequently fractured with 83.33%. We distinguished 50% of cases involving the proximal end of the humerus, 45.87% of cases of the humeral shaft and one case of concomitant fracture of the proximal end and that of the humeral shaft. The postoperative infection rate is zero in our series and we reported 1 case of distal locking screw breakage, 1 case of iterative fracture on short Telegraph nail, 1 case of proximal screw retraction on long Telegraph nail and 1 case of perforation of the humeral head with a proximal locking screw. Conclusion: humeral intramedullary nailing is a good alternative in fixing proximal end and humeral shaft fractures without considerable complications or damages for the rotator cuff muscles.

Temporal Changes in Reverse Torque of Locking-Head Screws Used in the Locking Plate in Segmental Tibial Defect in Goat Model

The objective of this study was to evaluate changes in peak reverse torque (PRT) of the locking head screws that occur over time. A locking plate construct, consisting of an 8-hole locking plate and 8 locking screws, was used to stabilize a tibia segmental bone defect in a goat model. PRT was measured after periods of 3, 6, 9, and 12 months of ambulation. PRT for each screw was determined during plate removal. Statistical analysis revealed that after 6 months of loading, locking screws placed in position no. 4 had significantly less PRT as compared with screws placed in position no. 5 (p < 0.05). There were no statistically significant differences in PRT between groups as a factor of time (p > 0.05). Intracortical fractures occurred during the placement of 151 out of 664 screws (22.7%) and were significantly more common in the screw positions closest to the osteotomy (positions 4 and 5, p < 0.05). Periosteal and endosteal bone reactions and locking screw backout occurred significantly more often in the proximal bone segments (p < 0.05). Screw backout significantly, negatively influenced the PRT of the screws placed in positions no. 3, 4, and 5 (p < 0.05). The locking plate-screw constructs provided stable fixation of 2.5-cm segmental tibia defects in a goat animal model for up to 12 months.

Outcomes of femoral de-rotation osteotomy for treatment of femoroacetabular impingement in adults with decreased femoral anteversion

Decreased femoral anteversion is an often overlooked factor in femoroacetabular impingement (FAI), with potential to exacerbate both cam and pincer type impingement, or itself be the primary cause. Femoral de-rotation osteotomy (FDO) is a surgical option for symptomatic patients with such underlying bony deformity. This study aimed to investigate outcomes of FDO for management of symptomatic FAI in the presence of decreased (<5°) femoral anteversion. Secondary aims were to describe the surgical technique and assess complications. This study included 33 cases (29 patients) with average pre-operative anteversion measuring –3.1° (true retroversion). At an average follow-up of 1.5 years (19.8 months), 97% reported significant improvement. The overall average post-operative International Hip Outcome Tool (iHOT-33) score of 70.6 points (r: 23–98) compared to the average pre-operative score of 42.8 points (r: 0–56) for the 11 patients with available pre-operative scores suggests an overall improvement. The minimal clinically important difference for the iHOT-33 is 6.1 points. Patients with both pre- and post-operative iHOT-33 scores available demonstrated a statistically and clinically significant improvement of 37.7 (r: 13–70) points. There were three cases (9%) of delayed union and two cases (6%) of non-union early in the series which prompted evolution of the technique. Locking screw removal was performed in 33% of patients for a resultant overall re-operation rate of 45%. The findings suggest improvement in patient-reported outcomes can be achieved with FDO for symptomatic FAI in the setting of decreased femoral anteversion (<5°).