Hardware removal: indications and expectations

High early post-operative complication rate after elective aseptic orthopedic implant removal of upper and lower limb

The necessity of orthopedic implant removal is under intense discussion and even if it is performed as an elective procedure, the risk of complications is present. Aim of the study was to identify parameters responsible for an increased risk of early post-operative complications after elective aseptic orthopedic implant removal. We reviewed 1,545 cases of aseptic and elective orthopedic implant removal between 2009 and 2011. The patient́s demographic data, time and duration of operation, patient́s comorbidities, and presence of complications in the first 4 weeks after implant removal were evaluated. Patients with signs of infection at the time of the surgical procedure were excluded from this study. 579 women and 966 men who underwent elective aseptic orthopedic implant removal were identified. Mean age at implant removal was 42 years and mean duration of the surgical procedure was 37 min. In this cohort, 70 patients (4.5%) underwent elective aseptic implant removal after 6pm. 52 patients (3.37%) operated on during daytime suffered from complications post-operatively and five patients (0.3%) who were operated on during the night experienced complications. The parameters age, sex, BMI, and surgeon showed no statistically significant differences for the risk of post-operative complications. Patients' comorbidities such as diabetes seem to have influence but were not statistically significant either. Patients with revision surgery since their first operation, nocturnal surgery and longer duration of the procedure showed a statistically significant higher risk for complications, especially in the lower leg. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1035-1039, 2018.

Biocompatibility and Efficiency of Biodegradable Magnesium-Based Plates and Screws in the Facial Fracture Model of Beagles

PURPOSE

A biodegradable magnesium alloy system has been developed as a substitute for conventional plates and screws made of titanium or absorbable polymer. However, previous studies were limited to small animal experiments using screws or wires. In the present study, we preliminarily evaluated the biocompatibility and effectiveness of human standard-size biodegradable magnesium-based plates and screws in facial fractures of beagles.

MATERIALS AND METHODS

Fracture lines were created bilaterally in the zygomatic arches of 6 beagles. They were fixed in situ with plates and screws made of magnesium alloy mixed with calcium and zinc (experimental group) or absorbable polymer (control group). Laboratory testing, radiologic imaging, histologic analysis, and mechanical testing were performed 4 weeks postoperatively.

RESULTS

Inflammatory reactions were not significantly increased in any animal. Mechanical testing showed greater ultimate load and structural stiffness in the experimental group. In the histologic analysis, the void area and bone regeneration area were increased in the experimental, and the implant area and soft tissue area were increased in the control group. Radiologically, 3-dimensional micro-computed tomography showed no differences in the bone gap area between the 2 groups. A temporary increase in hydrogen gas around the magnesium implants regressed spontaneously and did not affect bone healing significantly.

CONCLUSIONS

Magnesium-based biodegradable plates and screws showed good biocompatibility and offered considerable stability for fixating facial bone fractures in the early bone-healing process. These results show the possibilities for the future development of magnesium alloy plates and screws for craniomaxillofacial fixation in humans.

[Treatment of femur re-fracture with occult infection by using non-contact locking plate under deep fascia]

Objective

To investigate the effectiveness on the re-fracture of the femur with occult infection by using non-contact locking plate which was placed under the deep fascia.

Methods

Clinical data of 12 cases of occult infective re-fracture after femoral fracture operation were retrospectively analysed between January 2010 and December 2014. There were 8 males and 4 females with an age of 28-69 years (mean, 42.8 years). Femur re-fractured in 5 cases after 3 days to 4 weeks (mean, 10.6 days) of removal of internal fixation, including 4 cases of plate fixation and 1 case of intramedullary nail fixation; femur in 7 cases re-fractured because of breakage of internal fixator after 7-16 months (mean, 9.3 months) of internal fixation, including 5 cases of plate fixation and 2 cases of intramedullary nail fixation. The tissues near the fracture were collected for bacteria culturing and pathological examining. All the patients were treated by debriding the site of the fracture, bridging with the non-contact locking plate, and transplanting with granulated cancellous bone autograft. Intravenous infusion of antibiotics were used for 2-3 weeks after operation and oral administration for 4 weeks. The X-ray films were taken regularly and the function of the knees were evaluated by the Hospital for Special Surgery (HSS) score system.

Results

The results of bacteria culturing were positive in 8 patients and negative in 4 patients, and the pathological results of all the patients were confirmed to be chronic bone infection. All the fractures healed with no signs of exudation and ulceration of the incisions. The 12 patients were followed up 18-36 months (mean, 29.6 months). The fracture healed well and no re-fracture occurred. The fracture healing time was 14-22 weeks (mean, 18 weeks). At last follow-up, the function of the knee joint was excellent in 9 cases and good in 3 cases according to HSS score system.

Conclusion

The treatment of re-fractures after femur fracture operation needs to determine whether there is an occult infection, and non-contact locking plate placed under the deep fascia is an effective way for the re-fracture.

Complications during removal of stainless steel versus titanium nails used for intramedullary nailing of diaphyseal fractures of the tibia

Objectives

Intramedullary nailing is the treatment of choice for fractures of the tibial shaft, which might necessitate the nail removal due to complications in the long-term. Although considered as a low-risk procedure, intramedullary nail removal is also associated with certain complications. Here, we compared the most commonly used stainless steel and titanium nails with respect to the complications during removal and clinical outcome for intramedullary nailing of diaphyseal fractures of the tibia.

Patients and methods

Sixty-two patients (26 females, 36 males) were included in this retrospective study. Of the removed nails, 24 were of stainless steel and 38 of titanium. Preoperative and intraoperative parameters, such as implant discomfort, anterior knee pain, operating time and amount of bleeding, and postoperative outcomes were evaluated for each patient.

Results

Titanium nail group had more, but not statistically significant, intraoperative complications than stainless steel group during the removal of nails (p = .4498). Operating time and amount of intraoperative bleeding were significantly higher in titanium group than stainless steel group (p = .0306 and p < .001, respectively). Preoperative SF-36 physical component and KSS scores were significantly lower in patients who had removal of titanium nails than those of stainless steel nails, whereas there was no difference in terms of postoperative SF-36 and KSS scores.

Conclusion

In conclusion, although greater bone contact with titanium increases implant stability, nail removal is more difficult, resulting in more longer surgical operation and more intraoperative bleeding. Therefore, we do not recommend titanium nail removal in asymptomatic patients.

The Role of Implant Removal in Orthopedic Trauma

Although implant removal is common after orthopedic trauma, indications for removal remain controversial. There are few data in the literature to allow evidence-based decision-making. The risk of complications from implant removal must be weighed against the possible benefits and the likelihood of improving the patient's symptoms.

Supination-external rotation ankle fractures: analysis of clinical results after syndesmotic screw removal

Objective

To evaluate the postoperative results of patients with supination-external rotation ankle fractures who underwent syndesmotic screw (SS) removal.

Methods

Retrospective cohort study assessing the late postoperative results of 35 patients operated from January 2013 to June 2015. Patients undergoing treatment of rupture of the distal tibiofibular syndesmosis with SS fixation and who did not have any concomitant surgical injuries in sites other than the ankle were included. Patients who did not complete appropriate follow-up after surgery were excluded from the study.

Results

There was no statistical significant difference in the evaluated outcomes among the patients who had their SS removed and those who remained with the SS.

Conclusion

SS removal did not significantly alter the clinical results of patients surgically treated with SS for supination-external rotation fractures.

Femoral neck fractures after removal of hardware in healed trochanteric fractures

INTRODUCTION

Hardware removal in healed trochanteric fractures (TF) in the absence of infection or significant mechanical complications is rarely indicated. However, in patients with persistent pain, prominent material and discomfort in the activities of daily living, the implant is eventually removed. Publications of ipsilateral femoral neck fracture after removal of implants from healed trochanteric fractures (FNFARIHTF) just because of pain or discomfort are rare. The purpose of this systematic review of the literature is to report on the eventual risk factors, the mechanisms, the clinical presentation, and frequency, and to pay special emphasis in their prevention.

MATERIALS AND METHODS

A comprehensive review of the literature was undertaken using the PRISMA guidelines with no language restriction. Case reports of FNFARIHTF and series of TF with cases of FNFARIHTF due to pain or discomfort published between inception of journals to December 2016 were eligible for inclusion. Relevant information was divided in two parts. Part I included the analysis of cases of FNFARIHTF, with the objective of establishing the eventual risk factors, mechanisms and pathoanatomy, clinical presentation and diagnosis, treatment and prevention. Part II analyzed series of TF which included cases of FNFARIHTF for assessing the incidence of femoral neck fractures in this condition.

RESULTS

Overall 24 publications with 45 cases of FNFARIHTF met the inclusion criteria. We found that the only prevalent factors for FNFARIHTF were: 1) preexisisting systemic osteoporosis, as most patients were older and elder females, with lower bone mineral density and bone mass; 2) local osteoporosis as a result of preloading by the fixation device in the femoral neck, leading to stress protection, reducing the strain at the neck, and increasing bone loss and weakness; and 3) the removal of hardware from the femoral neck, with reduction of the failure strength of the neck. The femoral neck fractures were spontaneous, i.e. not related to trauma or fall, in 87.5% of the cases, mostly subcapital, and with no prevalence between displaced and undisplaced fractures. The clinical presentation was that of a spontaneous fracture, and most of the patients consulted because of hip pain and presented in the emergency room walking by themselves which led to delayed diagnosis in several instances. Radiological diagnosis was mostly with radiographs, though in some cases CT scans or MRI were necessary. The overall median incidence of this complication was 14.5% after hardware removal because of pain or discomfort in healed trochanteric fractures.

CONCLUSION

The risk factors for FNFARIHTF seem to be preexisisting systemic osteoporosis, local osteoporosis as a result of preloading by the fixation device in the femoral neck, and the removal of hardware from the femoral neck, with reduction of the strength of the neck. The clinical presentation may be obscure as most of the patients complain of hip pain of some days or weeks, and arrive in the hospital walking. Therefore, the attending physician should be alert in order to request the appropriate radiological investigation and if this is not clear CT scan or MRI should be done in order to diagnose promptly these "spontaneous" fractures. Treatment should be replacement surgery in most cases; however, there is some place for internal fixation especially in undisplaced fractures or younger patients. The occurrence of the femoral neck fracture after hardware removal may be prevented with re-osteosynthesis and the use of bone chips or bone substitutes. Finally, the relatively high incidence of this complication should alert orthopaedic surgeons to reduce the removal of hardware in healed trochanteric fractures to very selected cases.

Rate of and Risk Factors for Intermediate-Term Reoperation After Ankle Fracture Fixation: A Population-Based Cohort Study

OBJECTIVE

Establish baseline rates of and risk factors for reoperation within 1 or 2 years of ankle open reduction internal fixation (ORIF).

DESIGN

Retrospective, population-based cohort study.

SETTING

Two hundred two hospitals in Ontario, Canada (approximate population 13.6 million in 2014).

PATIENTS/PARTICIPANTS

Forty five thousand four hundred forty-four patients who underwent ankle ORIF performed by 710 different surgeons between January 1, 1994, and December 31, 2011.

MAIN OUTCOME MEASUREMENTS

Intermediate-term reoperation because of isolated implant removal, repeat ORIF, irrigation and debridement (I&D) for infection, or amputation. Multivariable logistic regression related potential prognostic factors (patient, provider, and injury) to reoperation.

RESULTS

There were 8906 patients who underwent at least one subsequent operation (19.6%). The most common procedure was isolated implant removal (18.1%); odds of removal being higher for females [odds ratio (OR), 1.53; 95% confidence interval (CI), 1.45-1.62; P < 0.001]. N = 674 patients (1.5%) underwent reoperation for another reason. The odds of repeat ORIF and I&D infection were greater for open fractures (OR 2.17; 95% CI, 1.22-3.86; P = 0.008 and OR 3.12; 95% CI, 1.94-5.03; P < 0.001). Odds of amputation was highest for diabetics (OR 7.42; 95% CI, 3.73-14.86; P < 0.001).

CONCLUSIONS

Isolated implant removal accounts for the vast majority of intermediate-term reoperations after ankle ORIF. Reoperation for other reasons (repeat ORIF, I&D, or amputation) was extremely rare, even among the highest risk patients. Concerns regarding reoperation for these reasons should not preclude operative treatment in any patient, provider, or injury group we considered.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Periprosthetic total knee fracture after remote reconstruction of the anterior cruciate ligament: a case report

Background

Distal femoral fracture is a rare, but significant, postoperative complication of anterior cruciate ligament reconstruction. However, there has not been a reported case of periprosthetic total knee arthroplasty fracture associated with a previous anterior cruciate ligament repair.

Case presentation

We report the case of a 51-year-old white man with a history of total knee arthroplasty and remote anterior cruciate ligament reconstruction, who presented with a distal femoral periprosthetic fracture at the site of a previous anterior cruciate ligament augmentation staple.

Conclusions

Based on these findings, it may be important to consider removal of previous anterior cruciate ligament hardware prior to total knee arthroplasty to reduce risk of periprosthetic fracture, which should be determined on a patient-specific basis.

Subcutaneous emphysema of the leg after hardware removal and bone allografting for infected non-union of the distal femur

Background

Infected non-unions of the supracondylar region of the femur are uncommon. Even though hardware removal is a common procedure, it may lead to complications, including neurovascular injury, refracture, worsening pain or recurrence of deformity.

Case presentation

We report on a male who developed subcutaneous emphysema of the leg after hardware removal and bone allografting for an infected non-union of the distal femur. He was managed by debridement of the surgical wound, antibiotic therapy, multiple fasciotomies, and application of a VAC (vacuum-assisted closure) system.

Conclusions

Although subcutaneous emphysema of the leg after hardware removal and bone allografting for infected non-union of the distal femur is extremely rare, the potential life treating complications and their potential impact on the functional status of the patient have to be taken into consideration when counseling patients about this procedure. Even when it is not possible to identify a bacterial pathogen responsible for the subcutaneous emphysema of the leg, prompt intervention may save the limb of the patient.

Functional Outcomes Post Lisfranc Injury-Transarticular Screws, Dorsal Bridge Plating or Combination Treatment?

OBJECTIVE

To identify whether transarticular screws, dorsal bridging plates or a combination of the 2 result in the best functional outcome after Lisfranc injury.

DESIGN

Case series.

SETTING

Level one trauma center.

PATIENTS

Fifty patients who underwent surgical fixation of Lisfranc injuries over a 6-year period were retrospectively reviewed.

INTERVENTION

One of 3 treatment arms: transarticular screw fixation alone, dorsal bridge plating alone or a combination of dorsal bridge and transarticular screw fixation.

MAIN OUTCOME MEASURES

The primary outcome measures were 1 of 2 midfoot scores-the American Orthopaedic Foot and Ankle Society (AOFAS) Midfoot Score and the Foot Function Index (FFI) Score. Secondary results included postoperative complications.

RESULTS

Quality anatomical reduction is the best predictor of functional outcomes (FFI-P = 0.008, AOFAS-P = 0.02). Functional outcomes with both FFI and AOFAS scores were not significantly associated with any of the fixation groups (FFI-P = 0.495, AOFAS-P = 0.654) on univariate analysis. Injury type by Myerson classification systems or open versus closed status was also not significantly associated with any fixation group. Open exposures were more likely to result in soft-tissue complications, but there was no significant difference in metalware failure or need for removal.

CONCLUSION

Functional outcomes after Lisfranc fractures are most dependant on the quality of anatomical reduction and not the choice of fixation implant used.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

In vivo study of microarc oxidation coated biodegradable magnesium plate to heal bone fracture defect of 3mm width

Microarc oxidation (MAO) coated magnesium (Mg) with improved corrosion resistance appeal increasing interests as a revolutionary biodegradable metal for fractured bone fixing implants application. However, the in vivo corrosion degradation of the implants and bone healing response are not well understood, which is highly required in clinic. In the present work, 10μm and 20μm thick biocompatible MAO coatings mainly composed of MgO, Mg₂SiO₄, CaSiO₃ and Mg₃(PO₄)₂ phases were fabricated on AZ31 magnesium alloy. The electrochemical tests indicated an improved corrosion resistance of magnesium by the MAO coatings. The 10μm and 20μm coated and uncoated magnesium plates were separately implanted into the radius bone fracture site of adult New Zealand white rabbits using a 3mm width bone fracture defect model to investigate the magnesium implants degradation and uninhibited bone healing. Taking advantage of the good biocompatibility of the MAO coatings, no adverse effects were detected through the blood test and histological examination. The implantation groups of coated and uncoated magnesium plates were both observed the promoting effect of bone fracture healing compared with the simple fracture group without implant. The releasing Mg²⁺ by the degradation of implants into the fracture site improved the bone fracture healing, which is attributed to the magnesium promoting CGRP-mediated osteogenic differentiation. Mg degradation and bone fracture healing promoting must be tailored by microarc oxidation coating with different thickness for potential clinic application.

Socioeconomic Factors Are Associated With Trends in Treatment of Pediatric Femoral Shaft Fractures, and Subsequent Implant Removal in New York State

BACKGROUND

Disparities exist in access to outpatient pediatric orthopaedic care. The purpose of this study was to assess whether disparities also exist in elective pediatric orthopaedic surgical procedures such as implant removal, and to determine which demographic and socioeconomic factors may be associated with differences in treatment.

METHODS

Children aged 7 to 18 inclusive who sustained femoral shaft fractures between the years 1997 and 2010 were identified in the New York State SPARCS database. Patient age, sex, race/ethnicity, insurance status, education, and poverty were identified. Factors associated with the method of fracture treatment were assessed through multivariate regression analysis. The subset of patients that received internal fixation were followed up until 2011 inclusive for implant removal. Factors associated with implant removal were assessed using a Cox proportional hazards survival analysis (time to implant removal).

RESULTS

Of the 3220 closed femoral shaft fractures identified, 2609 (81%) were treated with internal fixation, 9 (0.3%) had open treatment without implants, 203 (6.3%) were treated with external fixation, and 399 (12.4%) with closed methods. Patients with No Fault/Accident insurance by No Fault/Accident insurance were more likely to undergo internal fixation compared with patients with private insurance (P<0.001). Of the 3220 patients, 2572 were included in the implant removal subanalysis. Implant removal was performed in 725 (28.2%) patients. In the multivariate model, patients were more likely to undergo removal if they were younger (P<0.001), white [vs. black (P<0.001), vs. Hispanic (P=0.035), vs. other (P=0.001)], and lived in neighborhoods with less poverty (P=0.016). Insurance status was not a statistically significant predictor of implant removal.

CONCLUSIONS

There is an association between implant removal and younger age, white race, and higher socioeconomic status in children. Awareness of these disparities should prompt further evaluation of causation, whether it be from lack of evidence-based guidelines for implant removal, surgeon bias, variations in reimbursement, or disparities in access to care. Further study is recommended to better elucidate the indications for implant removal in children and the causes for the disparities identified here.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Removal of interlocking intramedullary nail for relieve of knee pain after tibial fracture repair

OBJECTIVE

To investigate the effects of intramedullary nail removal after tibial fracture repair.

METHODS

Sixty patients at our hospital were enrolled in a prospective study and divided into moderate/severe knee pain (visual analog scale (VAS) ≥ 4) and mild/no knee pain (VAS < 4) groups after interlocking intramedullary nailing. Variables studied included the distance from the tip of the nail to the tibial plateau and the front of the tibia on a normalized lateral X-ray, the VAS score of knee and ankle pain, the range of motion of the knee and ankle, and Johner-Wruhs criteria before, 6 weeks after operation, and at the last follow-up.

RESULTS

Fifty-seven patients were followed for a mean of 8.4 (2-17) months. In patients with moderate or severe knee pain intramedullary nail removal led to significant pain reductions ( p < 0.05). A significantly shorter distance from the tip of the nail to the tibial plateau (<10 mm) and the anterior border of tibia (<6 mm) was found in the 24 patients with moderate or severe knee pain. Knee pain VAS scores significantly lowered 6 weeks postoperatively and at the last follow-up, compared to before the operation ( p < 0.05). However, no significant changes occurred with respect to ankle pain VAS scores, range of motion, and Johner-Wruhs criteria ( p > 0.05).

CONCLUSION

For patients complaining knee pain after interlocking intramedullary nailing of tibial fractures, especially with a short distance from the tip of the nail tail to the tibial plateau (<10 mm) and the anterior border of the tibia (<6 mm) removal of the intramedullary nails relieved the pain significantly.

Inpatient orthopaedic hardware removal in children: A cross-Sectional study

INTRODUCTION

Few data describe the specific reasons for inpatient hardware removal in the pediatric population. This study was designed to understand the conditions necessitating inpatient removal following fracture surgery. Cost data was analyzed to understand the financial implications of these procedures.

METHODS

The Kids' Inpatient Database (KID) was evaluated for the year 2012. Patients undergoing open reduction internal fixation following upper and lower extremity fractures as well as those undergoing hardware removal due to hardware complications were identified using ICD-9 CM diagnosis and procedure codes. Univariable and multivariable logistic regression were used to determine predictors of surgical removal due to complications, controlling for patient demographics and comorbidities.

RESULTS

The most common indication for removal was infection (1141 patients; 32%), followed by mechanical dysfunction (923; 25.4%), and pain (472; 13%). Logistic regression analysis showed that femur fractures (OR = 8.27, 95% CI: 7.63-8.96) and tibia/fibula fractures (OR = 1.24, 95% CI: 1.17-1.35) were independent predictors of infection-related hardware removal (P < 0.001). Patients who underwent removal due to infection were more likely to have asthma (OR = 1.87, 95% CI: 1.62-2.07), smoke tobacco (OR = 1.12, 95% CI: 1.05-1.23), and suffer from developmental delays (OR = 1.32, 95% CI: 1.19-1.54) (P < 0.001). Average hospital charges and costs were $36,349 and $11,792 respectively.

CONCLUSION

While most commonly performed as an outpatient procedure, inpatient hardware removal occurs with relative frequency and is most often performed for infection, mechanical failure, or pain. Risk factors for infection-related removal were identified and provide a basis for further investigation.

Randomized, Prospective Comparison of Bioabsorbable and Steel Screw Fixation of Lisfranc Injuries

OBJECTIVE

This study's objective is to compare outcomes of bioabsorbable versus steel screws for treating Lisfranc injuries.

DESIGN

This research was conducted in a prospective and randomized manner between September 2008 and December 2013.

SETTING

This study was performed in the outpatient setting at a tertiary-level care center in a single surgeon's practice.

PATIENTS/PARTICIPANTS

Forty patients with acute Lisfranc injuries, amenable to open reduction and screw fixation, enrolled and presented for final follow-up.

INTERVENTION

Through randomization, 20 and 20 patients received bioabsorbable versus steel screws, respectively.

OUTCOME MEASUREMENTS

Function and pain were graded using the Foot and Ankle Ability Measures (FAAM) and a visual analog scale of pain. Radiographs were assessed for joint stability and degeneration.

RESULTS

For those with steel screws, the mean FAAM score increased from 24.9 to 89.6 of 100 and pain score decreased from 6.5 to 1.9 of 10 by latest follow-up. For those with absorbable screws, the mean FAAM score increased from 32.5 to 91.2 and pain score decreased from 4.7 to 1.3 by latest follow-up. These differences in final mean function (P = 0.4) and pain (P = 0.25) between the study groups were not statistically significant. Final radiographs showed no Lisfranc instability in any study patients, but rather midfoot arthritis in 4 and 2 patients with steel versus bioabsorbable screws, respectively. None of the patients who received steel screws had hardware-related problems, but 1 patient who received absorbable fixation developed an inflammatory reaction at a nonresorbed screw head at 2 years after surgery.

CONCLUSIONS

Bioabsorbable screws provide short-term results that are comparable and not significantly different from steel screws for treating unstable Lisfranc injuries. Both methods are predictable in improving function and pain, but using absorbable screws eliminates the need for hardware removal after such trauma.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Early results using a biodegradable magnesium screw for modified chevron osteotomies

This is the first larger study analyzing the use of magnesium-based screws for fixation of modified Chevron osteotomies in hallux valgus surgery. Forty-four patients (45 feet) were included in this prospective study. A modified Chevron osteotomy was performed on every patient and a magnesium screw used for fixation. The mean clinical follow up was 21.4 weeks. The mean age of the patients was 45.5 years. Forty patients could be provided with the implant, in four patients the surgeon decided to change to a standard metallic implant. The AOFAS, FAAM and pain NRS-scale improved markedly. The hallux valgus angle, intermetatarsal angle and sesamoid position improved significantly. Seven patients showed dorsal subluxation, rotation or medial shifting of the metatarsal heads within the first 3 months. One of these patients was revised, in all others the findings were considered clinically not significant or the patients refused revision. This study shows the feasibility of using magnesium screws in hallux valgus-surgery. Surgeons starting with the use of these implants should be aware of the proper handling of these implants and should know about corrosion effects during healing and its radiographic appearance. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:2207-2214, 2016.

An antibacterial and absorbable silk-based fixation material with impressive mechanical properties and biocompatibility

Implant-associated infections and non-absorbing materials are two important reasons for a second surgical procedure to remove internal fixation devices after an orthopedic internal fixation surgery. The objective of this study was to produce an antibacterial and absorbable fixation screw by adding gentamicin to silk-based materials. The antibacterial activity was assessed against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) in vitro by plate cultivation and scanning electron microscopy (SEM). We also investigated the properties, such as the mechanical features, swelling properties, biocompatibility and degradation, of gentamicin-loaded silk-based screws (GSS) in vitro. The GSS showed significant bactericidal effects against S. aureus and E. coli. The antibacterial activity remained high even after 4 weeks of immersion in protease solution. In addition, the GSS maintained the remarkable mechanical properties and excellent biocompatibility of pure silk-based screws (PSS). Interestingly, after gentamicin incorporation, the degradation rate and water-absorbing capacity increased and decreased, respectively. These GSS provide both impressive material properties and antibacterial activity and have great potential for use in orthopedic implants to reduce the incidence of second surgeries.

Reasons for Implant Removal after Distal Radius Fractures

Background: With new low profile locked volar plate designs for distal radius fractures, soft tissue complications are uncommon. However, there are still patients who request to have their implants removed. In this study, we retrospectively reviewed the reasons for this.

Methods: We reviewed the hospital operative records of patients who had operative fixation of wrist fractures between November 2008 and May 2009. We examined the clinical records of these patients in order to ascertain if there was a difference in patient demographics between those who eventually had their implants removed and those who had their implants retained. We also noted down the reasons for removal of implants.

Results: In the period of study, 165 patients had operative fixation of their distal radius fractures, of which 44 (26.7%) had had their implants eventually removed. These patients tended to be younger (mean age of 37.1 years compared to 45.5 years in those who retained their implants). We also found a correlation between removal of implants and the presence of ulnar implants, as well as hand dominance. Reasons for implant removal were symptomatic irritation/implant prominence (15), joint stiffness requiring arthrolysis (6), infection (2), malunion (2), and patients who did not have a clinical reason (19).

Conclusions: Our results suggest the involvement of other psychosocial factors, such as cultural attitudes towards the presence of implants within the body. In light of our results, we also suggest that ulnar styloid fractures be treated non-operatively.

The Analysis of Biomechanical Properties of Proximal Femur after Implant Removal

Introduction. To compare the biomechanical stability of the femur following the removal of proximal femoral nail antirotation (PFNA-II) and dynamic hip screw (DHS). Material and Methods. 56 paired cadaveric femurs were used as experimental and control groups. In the experimental group, PFNA-II and DHS were randomly inserted into femurs on both sides and then removed. Thereafter, compression load was applied until fracture occurred; biomechanical stability of the femurs and associated fracture patterns were studied. Results. The ultimate load and stiffness of the control group were 6227.8 ± 1694.1 N and 990.5 ± 99.8 N/mm, respectively. These were significantly higher than experimental group (p = 0.014, <0.001) following the removal of PFNA-II (4085.6 ± 1628.03 N and 656.3 ± 155.3 N/mm) and DHS (4001.9 ± 1588.3 N and 656.3 ± 155.3 N/mm). No statistical differences in these values were found between the 2 device groups (p = 0.84, 0.71), regardless of age groups. However, fracture patterns were different between two devices, intertrochanteric and subtrochanteric fractures. Conclusions. Mechanical stability of the proximal femurs does not differ after the removal of 2 different of fixation devices regardless of the age. However, it was significantly lower compared to an intact femur. Different fracture patterns have been shown following the removal of different fixation devices as there are variations in the site of stress risers for individual implants.

Incidence and risk factors for removal of an internal fixation following surgery for ankle fracture: A retrospective cohort study of 997 patients

BACKGROUND

Implant removal in ankle fractures treated by open reduction and fixation is often based on diffuse complaints. This study determined the incidence of implant removal and identified risk factors for two principal causes for removal: complaints and surgical site infection (SSI).

METHODS

Retrospective cohort study involving 997 patients operated on 2009-2011 with follow-up through to 2013. The incidence of implant removal was analysed using competing risk analysis. Risk factors for implant removal were assessed using cause-specific hazard ratios (HRs) from a Cox regression analysis.

RESULTS

The mean age at surgery was 51.6 years, 550 (55%) of the patients were female, and 170 patients (17%) had implant removal: 144 due to complaints and 26 due to infection. Multivariable HRs for implant removal due to complaints were 0.70 for male sex (p=0.047), 0.79 for each 10-year increase in age (p<0.001), 0.70 for treatment with a syndesmosis screw (p=0.038), and 1.09 for each 15-min increase in operation duration (p=0.007). HRs for hardware removal due to infection were 1.42 for each 10-year increase in age (p=0.006) and 3.15 for current smoking (p=0.005).

CONCLUSION

In total 17% of patients had implant removal after open reduction and fixation; the majority because of subjective complaints. The risk factors for implant removal were different for removal due to complaints than for those removed due to infection. This information may be used to inform patients about the risk and risk factors for future implant removal.

Water-based lubricant as an adjunct to wound toilet: Validation of a technique by experiment

INTRODUCTION

Metal debris can produce a foreign body inflammatory reaction or as third body wear in the situation of joint arthroplasty. We evaluate a simple method for reducing this debris using a sterile water-based lubricating gel.

MATERIALS AND METHODS

Eight experimental surgical models consisting of porcine muscle overlying a polyethylene tube with a titanium locking plate and screws secured were constructed. Four models had water based lubricating gel applied to the wound edges, four were left without as controls. Image were then captured before and after irrigation from which the amount of debris could be quantified.

RESULTS

The reduction of surface area covered by debris for models with water-based gel was greater (p=0.001). The average reduction in surface area was 27.2% for the control group and 94.1% for the models covered with lubricating gel.

CONCLUSION

We show that using a safe, inexpensive and easily available water-based lubricating gel reduces the amount of embedded debris when burring metal implants using a high-speed burr.

Indications for prophylactic osteosynthesis associated with curettage in benign and low-grade malignant primitive bone tumors of the distal femur in adult patients: a case series

BACKGROUND

The aim of the study was to evaluate whether the use of preventive osteosynthesis after curettage in benign and primitive low-grade malignant bone tumor localized in the distal femur in adult patients provides sufficient mechanical stability to the system as to allow weight-bearing and reduce the risk of postoperative fracture. Additionally, lower limb function after curettage and preventive osteosynthesis was evaluated.

MATERIALS AND METHODS

We analyzed twelve cases of benign and low-grade malignant bone lesions of the distal femur in adult patients treated in our orthopedic department between 2008 and 2011 with curettage, bone filling and preventive osteosynthesis. All patients were treated with curettage with the use of high-speed cutters, plus liquid nitrogen as local adjuvant in low-grade malignant lesions, and filling of the lesion with bone graft or allograft or acrylic cement, followed by osteosynthesis.

RESULTS

No fractures or major complications were observed; good function of the knee was observed.

CONCLUSION

We recommend preventive osteosynthesis after curettage in patients with very large lesions (>5 cm, >60 cm³) or high functional requirements, in obese patients, and when local adjuvants are used.

LEVEL OF EVIDENCE

Level IV retrospective case-series study.

Removal of Infected Posterior Spinal Implants: Be Prepared to Transfuse

STUDY DESIGN

Single-center retrospective review of spinal deformity patients undergoing removal of infected posterior spinal fusion implants over a 10-year period.

OBJECTIVE

To evaluate the intraoperative blood loss and perioperative complications of implant removal in posterior spinal fusions.

SUMMARY OF BACKGROUND DATA

To our knowledge, no studies examine blood loss or complications associated with removal of infected spinal implants in spinal deformity.

METHODS

A retrospective review of 28 consecutive cases of infected posterior spinal fusion implant removal from 2003 to 2012 was performed. Exclusion criteria were patients with ≤6 levels of instrumentation, a partial removal of implants or a bleeding disorder.

RESULTS

The average estimated blood loss was 465 mL (range 100-1,505 mL). Average estimated blood volume was 3,814 mL (range 1,840-9,264 mL). The average percentage of estimated blood loss was 14.2% (range 1.9%-43.5%). On postoperative labs obtained at the conclusion of the procedure, there was an average loss in hematocrit of 6.6 from preoperative values. Seventy-one percent of patients (20/28) received a blood transfusion; 39% (11/28) of these received a transfusion intraoperatively and 54% (15/28) received a transfusion postoperatively. Forty-six percent of patients (13/28) experienced an associated medical complication in the postoperative period. Among these 13, there were 16 total complications, with the most common being seizures (4/16), pneumonia (2/16), and sepsis (2/16). Average hospital stay was 14 days (range 4-52).

CONCLUSION

Seventy-one percent of patients undergoing removal of infected spinal implants received a blood transfusion. We recommend having blood products available when removing posterior spinal instrumentation >6 levels. Patients and families should be counseled on the high risk of complications and expected hospital stay in these cases.

LEVEL OF EVIDENCE

Level III.

Easy and Inexpensive Technique for Removal of Round Headed, Jammed Locking Screws in Distal Tibial Interlocking Plate

Introduction:

The advent of locking plates has brought new problems in implant removal. Difficulty in removing screws from a locking plate is well-known. These difficulties include cold welding between the screw head and locking screw hole, stripping of the recess of the screw head for the screwdriver, and cross-threading between threads in the screw head and screw hole. However, there are cases in which removal is difficult. We describe a new technique for removing a round headed, jammed locking screws from a locking plate.

Case Report:

55 years old male patient received a locking distal tibial plate along with distal fibular plate 3years back from UAE. Now patient came with complaint of non-healing ulcer over medial aspect of lower 1/3rd of right leg from past 1 year. Non operative management did not improve the symptoms. The patient consented to implant removal, with the express understanding that implant removal might be impossible because already one failed attempt had been performed at some other hospital six months back. We then decided to proceed with the new technique. The rest of the proximal screws were removed using a technique not previously described. We used stainless steel metal cutting blades that are used to cut door locks or pad locks to cut the remaining stripped headed screws.

Conclusion:

This technique is very quick, easy to perform and inexpensive because the metal cutting blades which are used to cut the screws are very cheap. Yet it is very effective technique to remove the stripped headed or jammed locking screws. It is also very less destructive because of very less heat production during the procedure there is no problem of thermal necrosis to the bone or the surrounding soft tissue.

Intramedullary Mg2Ag nails augment callus formation during fracture healing in mice

Intramedullary stabilization is frequently used to treat long bone fractures. Implants usually remain unless complications arise. Since implant removal can become technically very challenging with the potential to cause further tissue damage, biodegradable materials are emerging as alternative options. Magnesium (Mg)-based biodegradable implants have a controllable degradation rate and good tissue compatibility, which makes them attractive for musculoskeletal research. Here we report for the first time the implantation of intramedullary nails made of an Mg alloy containing 2% silver (Mg2Ag) into intact and fractured femora of mice. Prior in vitro analyses revealed an inhibitory effect of Mg2Ag degradation products on osteoclast differentiation and function with no impair of osteoblast function. In vivo, Mg2Ag implants degraded under non-fracture and fracture conditions within 210days and 133days, respectively. During fracture repair, osteoblast function and subsequent bone formation were enhanced, while osteoclast activity and bone resorption were decreased, leading to an augmented callus formation. We observed a widening of the femoral shaft under steady state and regenerating conditions, which was at least in part due to an uncoupled bone remodeling. However, Mg2Ag implants did not cause any systemic adverse effects. These data suggest that Mg2Ag implants might be promising for intramedullary fixation of long bone fractures, a novel concept that has to be further investigated in future studies.

STATEMENT OF SIGNIFICANCE

Biodegradable implants are promising alternatives to standard steel or titanium implants to avoid implant removal after fracture healing. We therefore developed an intramedullary nail using a novel biodegradable magnesium-silver-alloy (Mg2Ag) and investigated the in vitro and in vivo effects of the implants on bone remodeling under steady state and fracture healing conditions in mice. Our results demonstrate that intramedullary Mg2Ag nails degrade in vivo over time without causing adverse effects. Importantly, radiographs, μCT and bone histomorphometry revealed a significant increase in callus size due to an augmented bone formation rate and a reduced bone resorption in fractures supported by Mg2Ag nails, thereby improving bone healing. Thus, intramedullary Mg2Ag nails are promising biomaterials for fracture healing to circumvent implant removal.

Role of Sonication for Detection of Infection in Explanted Orthopaedic Trauma Implants

OBJECTIVES

Sonication is a new technology that uses high-frequency sound waves to mechanically dislodge bacteria adherent in biofilms. Unlike arthroplasty, its role in orthopaedic trauma has not been described. The goal of this study was to explore the utility of sonication in orthopaedic trauma.

DESIGN

Retrospective review.

SETTING

Level I trauma center.

PATIENTS

One hundred forty-six sonicated metallic orthopaedic devices from September 2010 to May 2013 were included. Patients were divided into 3 groups: clinically infected, elective implant removals, and nonunion.

INTERVENTION

Sonication culture results were retrospectively reviewed for all patients undergoing implant removal.

OUTCOMES

Sonication results were the primary study outcome and were considered positive for culture growth if equal to or greater than 20 colony-forming units per plate.

RESULTS

In 32 patients with clinical infection, tissue cultures were positive in 30 (94%) and negative in 2 (6%). In contrast, sonication cultures were positive in 19 patients (59%) and did not identify additional organisms. Of the 72 patients who underwent elective implant removal, 52 had pain. Sonication cultures were positive in 5 of these 52 patients (10%) and in 0 of 20 patients with no pain. Sonication culture results were negative in all 42 patients who underwent nonunion surgery.

CONCLUSIONS

Sonication of orthopaedic trauma implants in patients with clinically apparent infection or "aseptic" nonunion offered negligible additional information. Sonication demonstrated a positive microbiologic yield in a subset of patients with painful implants; further research is required to better establish the frequency of subclinical infection and to determine the diagnostic role of traditional cultures and sonication.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

An in vivo model to assess magnesium alloys and their biological effect on human bone marrow stromal cells

Magnesium (Mg) alloys have many unique qualities which make them ideal candidates for bone fixation devices, including biocompatibility and degradation in vivo. Despite a rise in Mg alloy production and research, there remains no standardized system to assess their degradation or biological effect on human stem cells in vivo. In this study, we developed a novel in vivo model to assess Mg alloys for craniofacial and orthopedic applications. Our model consists of a collagen sponge seeded with human bone marrow stromal cells (hBMSCs) around a central Mg alloy rod. These scaffolds were implanted subcutaneously in mice and analyzed after eight weeks. Alloy degradation and biological effect were determined by microcomputed tomography (microCT), histological staining, and immunohistochemistry (IHC). MicroCT showed greater volume loss for pure Mg compared to AZ31 after eight weeks in vivo. Histological analysis showed that hBMSCs were retained around the Mg implants after 8 weeks. Furthermore, immunohistochemistry showed the expression of dentin matrix protein 1 and osteopontin around both pure Mg and AZ31 with implanted hBMSCs. In addition, histological sections showed a thin mineral layer around all degrading alloys at the alloy-tissue interface. In conclusion, our data show that degrading pure Mg and AZ31 implants are cytocompatible and do not inhibit the osteogenic property of hBMSCs in vivo. These results demonstrate that this model can be used to efficiently assess the biological effect of corroding Mg alloys in vivo. Importantly, this model may be modified to accommodate additional cell types and clinical applications.

STATEMENT OF SIGNIFICANCE

Magnesium (Mg) alloys have been investigated as ideal candidates for bone fixation devices due to high biocompatibility and degradation in vivo, and there is a growing need of establishing an efficient in vivo material screening system. In this study, we assessed degradation rate and biological effect of Mg alloys by transplanting Mg alloy rod with human bone marrow stromal cells seeded on collagen sponge subcutaneously in mice. After 8 weeks, samples were analyzed by microcomputed tomography and histological staining. Our data show that degrading Mg alloys are cytocompatible and do not inhibit the osteogenic property of hBMSCs in vivo. These results demonstrate that this model can be used to efficiently assess the biological effect of corroding Mg alloys in vivo.

Complications following implant removal in patients with proximal femur fractures - an observational study over 16 years

BACKGROUND

Fractures of the proximal femur commonly occur but the majority of orthopaedic surgeons do not consider general hardware removal as a routine necessity. Indications and time interval for hardware removal in this special selected patient group is still controversial. Therefore we performed a retrospective study to address the following questions: 1) Is there a difference between the medically- (infection, mechanical problems, implant failure) and non-medically indicated group (patients demand, meteoro-sensitivity, foreign body sensation) in relation to complications? 2) Is there a correlation regarding time interval between implantation and removal comparing these two groups? 3) Is there a context related refracture rate? 4) Should non-medically indicated implant removal (IR) be performed due to persistent pressure from the patient?

HYPOTHESIS

We hypothesized that non-medically indicated implant removals should be avoided due to a significantly higher number of associated complications.

PATIENTS AND METHODS

A total of 371 consecutive patients with 424 hardware removal procedures following a proximal femur fracture, between 08/1992 and 11/2008, have been included. Study population was divided into two groups according to their indication for implant removal: medically indicated group (MIR) consisted of 299 patients (80.59%) and 72 patients (19.41%) were assigned to the non-medically indicated (NMIR) group.

RESULTS

In the NMIR subgroup a total of (n = 21) 28% complications occurred compared to 11.46% in the MIR subgroup; (P < 0.005), 86.51% of IR in the MIR group were performed within 1.5 years, compared to 79.17% in the NMIR group after 2 to 3.5 years (NS). In the MIR group 1 refracture occurred, compared to 4 in the NMIR group (NS).

CONCLUSION

Non-medically indicated implant removal should be avoided due to the higher complication rate of 28%. Surgeons and patients should be aware of the imminent complications and therefore implant removal should only be performed for good medical reasons.

LEVEL OF EVIDENCE

Level IV. Historical case study.

Implant Removal After Internal Fixation of a Femoral Neck Fracture: Effects on Physical Functioning

OBJECTIVES

The effect of implant removal after internal fixation of a femoral neck fracture on physical functioning was analyzed. Characteristics of patients who had their implant removed were studied, as it is currently unknown from which type of patients implants are removed and what effect removal has on function.

DESIGN

Secondary cohort study alongside a randomized controlled trial.

SETTING

Multicenter study in 14 hospitals.

PATIENTS AND INTERVENTION

Patients who had their implant removed after internal fixation of a femoral neck fracture are compared with patients who did not.

MAIN OUTCOME MEASUREMENTS

Patient characteristics and quality of life (Short Form 12, Western Ontario McMaster Osteoarthritis Index) were compared. Matched pairs were selected based on patient/fracture characteristics and prefracture physical functioning.

RESULTS

Of 162 patients, 37 (23%) had their implant removed. These patients were younger (median age: 67 vs. 72 years, P = 0.024) and more often independently ambulatory prefracture (100% vs. 84%, P = 0.008) than patients who did not. They more often had evident implant back-out on x-rays (54% vs. 34%, P = 0.035), possibly related to a higher rate of Pauwels 3 fractures (41% vs. 22%, P = 0.032). In time, quality of life improved more in implant removal patients [+2 vs. -4 points, Short Form 12 (physical component), P = 0.024; +9 vs. 0 points, Western Ontario McMaster Osteoarthritis Index, P = 0.019].

CONCLUSIONS

Implant removal after internal fixation of a femoral neck fracture positively influenced quality of life. Implant removal patients were younger and more often independently ambulatory prefracture, more often had a Pauwels 3 fracture, and an evident implant back-out. Implant removal should be considered liberally for these patients if pain persists or functional recovery is unsatisfactory.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Metal implant removal: benefits and drawbacks--a patient survey

BACKGROUND

Hardware removals are among the most commonly performed surgical procedures worldwide. Current literature offers little data concerning postoperative patient satisfaction. The purpose of our study was to evaluate the patients' point of view on implant removal.

METHODS

We surveyed patients of a German level one trauma center, who underwent hardware removal in 2009 and 2010, with regard to their personal experiences on implant removal. Exclusively, data obtained out of the survey were analyzed.

RESULTS

In 332 patients surveyed, most hardware removals were performed at the ankle joint (21%) followed by the wrist (15%). The most frequent indication was a doctor's recommendation (68%), followed by pain (31%) and impaired function (31%). Patient reported complication rate of implant removal was 10%. Importantly, after implant removal because of pain or impaired function patients reported an improvement in function (72%) as well as decreased pain (96%). 96% of all responding patients and 66% of the patients who suffered from subsequent complications would opt for surgical implant removal again.

CONCLUSION

In summary, despite the challenging and frequently troublesome nature of surgical hardware removal our data contradicts the widely held view that implant removal is often without a positive effect on the patients. These findings may influence the surgeons' attitude towards implant removal and their day-to-day routine in patient counseling.

Retrieval of broken iliosacral screws: the power of a push screw

Percutaneous iliosacral screw fixation is a common technique that is widely used for unstable posterior pelvic ring disruptions. Complications of posterior percutaneous iliosacral screw fixation include implant malpositioning and hardware failure. Removal of iliosacral screws in broken or symptomatic hardware is sometimes necessary. To our knowledge, there are few reports addressing pelvic implant removal, and most of those report on anterior pelvic implants and symphyseal plates. There are no reports describing techniques for retrieval of broken iliosacral screws. We present two cases involving removal of broken sacroiliac screws, review the literature regarding iliosacral implant extraction, and identify important aspects of safe extraction of iliosacral screws and the potential complications associated with their retrieval. We further describe a novel and powerful technique to facilitate percutaneous removal of broken screw fragments, using a "push screw" to drive a broken screw fragment from a position buried in bone.

Comparison of plain radiography and CT in postoperative evaluation of ankle fractures

AIM

To compare postoperative plain radiographs with computed tomography (CT) post-processing images in evaluating the quality of anatomical reduction and internal fixation of ankle fractures.

MATERIALS AND METHODS

A total of 168 patients who sustained closed ankle fracture and were treated with open reduction and internal fixation in East Hospital were reviewed. Postoperative plain radiographs and CT post-processing images were evaluated. The observation was performed under volume-rendering mode and multiplanar reconstruction mode. The assessment was performed by two independent orthopaedic surgeons. The inter- and intra-observer variations were analysed by kappa statistics. The differences between plain radiographs and CT post-processing images were compared using χ(2) test (McNemar's test).

RESULTS

Inter- and intra-observer agreement was almost perfect (0.813-1.000) using CT post-processing images, which was higher than that using plain radiographs (0.323-0.848). More non-anatomical reduction could be recognised in the supination-external rotation (SER), supination-adduction (SAD), pronation-external rotation (PER), and overall groups (p<0.05) and more poor internal fixation could be recognised in the SER, SAD, and overall groups (p<0.05) using CT post-processing images than using radiographs.

CONCLUSION

More residual articular step, fracture fragment displacement, and poor internal fixation could be detected by CT post-processing images than plain radiographs.

In vivo study of magnesium plate and screw degradation and bone fracture healing

Each year, millions of Americans suffer bone fractures, often requiring internal fixation. Current devices, like plates and screws, are made with permanent metals or resorbable polymers. Permanent metals provide strength and biocompatibility, but cause long-term complications and may require removal. Resorbable polymers reduce long-term complications, but are unsuitable for many load-bearing applications. To mitigate complications, degradable magnesium (Mg) alloys are being developed for craniofacial and orthopedic applications. Their combination of strength and degradation make them ideal for bone fixation. Previously, we conducted a pilot study comparing Mg and titanium devices with a rabbit ulna fracture model. We observed Mg device degradation, with uninhibited healing. Interestingly, we observed bone formation around degrading Mg, but not titanium, devices. These results highlighted the potential for these fixation devices. To better assess their efficacy, we conducted a more thorough study assessing 99.9% Mg devices in a similar rabbit ulna fracture model. Device degradation, fracture healing, and bone formation were evaluated using microcomputed tomography, histology and biomechanical tests. We observed device degradation throughout, and calculated a corrosion rate of 0.40±0.04mm/year after 8 weeks. In addition, we observed fracture healing by 8 weeks, and maturation after 16 weeks. In accordance with our pilot study, we observed bone formation surrounding Mg devices, with complete overgrowth by 16 weeks. Bend tests revealed no difference in flexural load of healed ulnae with Mg devices compared to intact ulnae. These data suggest that Mg devices provide stabilization to facilitate healing, while degrading and stimulating new bone formation.

Possible predictors for difficult removal of locking plates: A case-control study

INTRODUCTION

Difficult removal of locking plates including less invasive stabilisation systems (LISSs) and locking compression plates (LCPs) sometimes occur. However, investigations of the mechanisms and correlated factors of complicated removal remain scant. This study aims to identify correlated factors for the difficult removal of locking plates and to propose suggestions for decision making regarding implant removal and the prevention of complicated removal.

MATERIALS AND METHODS

In total, 308 consecutive patients who underwent LCP/LISS removal from Sep. 2004 to Nov. 2013 were assessed. Using the Mann-Whitney U test, we analysed the correlation between difficult removal and the duration between open reduction and internal fixation (ORIF) and implant removal as well as the correlation between difficult removal and the patients' age. Using Chi Square test, we assessed the correlations between complicated removal and the size, location, insertion technique and cortical purchase of the locking head screw (LHS). Correlated factors were separately determined in upper and lower extremities. Rates of difficult removal in different fracture locations were evaluated, and postoperative complications were documented.

RESULTS

Of the total 308 patients, thirty-seven had intra-operative difficulties, and six patients experienced postoperative complications. Six out of fifteen patients with peri-elbow fractures and five out of seventeen patients with femur fractures suffered difficult removal, while four out of one hundred patients with malleolar fractures had intra-operative difficulties. Difficulties were experienced with 30 of 338 LCPs, 7 of 32 LISSs, 67 of 1533 small-diameter (≤ 3.5-mm) LHSs, and 12 of 442 large-diameter (≥ 4.5-mm) LHSs. Three LCPs and seventeen small-diameter LHSs were retained. A longer interval between ORIF and removal, younger age and bicortical screws correlated with difficult removal in the upper extremities, and a longer duration before removal, small-diameter LHS and minimally invasive insertion of LHS were predictors in the lower extremities.

CONCLUSIONS

Complications occur with LCP/LISS removal, and it should not be a routine procedure. If removal is indicated, performing surgery as soon as radiographs show fracture healing is recommended. Different considerations should apply when making decisions and removing implants from patients with different fracture sites.

Removal of forearm plate leads to a high risk of refracture: decision regarding implant removal after fixation of the forearm and analysis of risk factors of refracture

INTRODUCTION

Plate fixation is the gold standard for the treatment of forearm fractures at present, and whether or not to remove the implant after bone union remains controversial. This study demonstrated some cases of refracture in adult forearm fractures after bone union and discussed the risk factors for decision-making regarding implant removal.

METHODS

We reviewed patients with forearm diaphyseal fractures (including the radius, ulna, or both bones) who received open reduction and internal fixation (ORIF) from January 2008 to May 2011 in our institute. Fracture type was classified according to the AO/OTA system. All patients were fixed with a 3.5-mm dynamic compression plate. The patients were divided into two main groups: group A received implant removal after bone union, and group B retained the implant.

RESULTS

There were 122 patients (170 bones) included in this study (40 females and 82 males). In group A, 7/51 patients (8/62 bones; 12.9 %) had refracture. As classified by the AO/OTA classification, one patient was classified as type A1, one patient as type A2, two patients as type A3, and three patients as type B3. All patients suffered refracture without high-energy trauma. In group B, the refracture rate was 2.77 %, and all were caused by high-energy trauma. Patients with refracture had a shorter time interval between ORIF and implant removal. The possible risk factors of refracture in this study included a wedge bone defect on plain film, implant removal performed after less than 18 months, and AO/OTA type B fracture.

CONCLUSION

The incidence of refracture was significantly lower in the group that retained the implant. Routine implant removal after bone union in adult forearm fractures is not recommended due to the higher refracture rate.

Hollow mill for extraction of stripped titanium screws: an easy, quick, and safe technique

Removal of jammed titanium screws can be difficult due to the problem of stripping of the hexagonal heads of the screws. We present a technique of extraction of stripped screws with the use of a standard 4.5 mm stainless steel hollow mill in a patient of peri-implant fracture of the radius fixed with a titanium locking plate 2 years back. The technique is quick, safe, and cost effective.

Cemented total hip arthroplasty with retention of some existing hardware

We report a case of a 63-year-old man who presented an end stage hip osteoarthritis 42 years after a proximal femoral osteotomy performed for the treatment of an intracapsular femoral neck fracture. A cemented total hip arthroplasty was implanted using a standard posterior approach. The osteotomy hardware was totally covered with a new cortical bone formation. A layer of bone tissue was removed, the screw heads were broken and the nail plate was also removed. The screw threaded portions were retained because they did not interfere with cemented femoral stem implantation. Fourteen years after total hip arthroplasty, the patient reported no pain and expressed high satisfaction with the surgery. The hip radiograph showed wear of the polyethylene cup and no periprosthetic osteolysis. Retention of hardware can be considered, especially in patients who have had hardware for several years, without any negative symptoms.

Post-traumatic elbow rotational stiffness

BACKGROUND

The elbow is an important but complex structure, with movement in both the sagittal plane in flexion and extension, as well as the rotational plane in forearm supination and pronation. Trauma is a common cause of elbow stiffness, which significantly hampers daily function. There are currently no gold-standard management guidelines for post-traumatic elbow stiffness, and most of the published literature focuses solely on the sagittal plane of motion.

METHODS

This is a retrospective case series reviewing all patients who underwent a surgical release for treatment of post-traumatic elbow stiffness during a 36-month period. Motion range and the shortened version of the Disabilities of the Arm, Shoulder and Hand scores were serially measured and analyzed.

RESULTS

The results obtained showed that both the sagittal and rotational range of motion directly influenced upper limb function; however, the relationship between these two motion planes was weak, meaning that both sagittal and rotational motion in the elbow need be addressed individually. Post-traumatic elbow stiffness could be aptly managed by various surgical approaches, including arthroscopic-assisted procedures; these were all effective in increasing both the sagittal and rotational range of motion. More importantly, this gain in range translated to a statistically significant improvement in upper limb function.

CONCLUSIONS

Management of elbow stiffness needs to be tackled in both the sagittal and rotational motion planes.

Treatment of distal tibial shaft fractures by three different surgical methods: a randomized, prospective study

PURPOSE

A few studies focused on the methods of treatment for displaced distal tibial shaft fractures have been published, all of which compared two different methods. In this randomized, prospective study, we aimed to compare minimally invasive plate osteosynthesis, locking intramedullary nail stabilization and external fixation combined with limited open reduction and absorbable internal fixation for distal tibial shaft fractures by assessing complications and secondary procedures.

METHODS

From November 2002 to June 2012, 137 skeletally mature patients with displaced distal tibial shaft fractures with or without fibula fracture were randomized to be treated by minimally invasive plate osteosynthesis (group A, n = 46), locking intramedullary nail (group B, n = 46) or external fixation combined with limited open reduction and absorbable internal fixation (group C, n = 45). Age, gender, mechanism of injury, fracture pattern and presence of open fracture were equally distributed among the three groups. Indexes for evaluation included hospital stay, operative time, time to radiographic union, union status, infection and the incidence of re-operation. Mazur ankle score was introduced for functional evaluation. Statistics Analysis System (SAS) 9.2 was used for analysis.

RESULTS

A total of 121 patients were included in the final analysis (group A 42, group B 40 and group C 39) and evaluated after a mean of 14.8 months follow-up. There was no significant difference (P > 0.05) in hospital stay, time to radiographic union and the incidence of union status among the three groups. Although group C was associated with less secondary procedures versus groups A and B, it was related with more pin tract infections (15.4 %). Anterior knee pain occurred frequently after locking intramedullary nailing (37.5 %) and the irritation symptoms were more frequently encountered in group A (59.5 %). There was no difference in ankle function between the three methods after operation (P > 0.05).

CONCLUSIONS

We consider that the minimally invasive plate osteosynthesis, locking intramedullary nail stabilization and external fixation combined with limited open reduction and absorbable internal fixation techniques are all efficient methods for treating distal tibia fractures. With its wide indications, external fixation combined with limited open reduction and absorbable internal fixation leads to minimal soft tissue complication, good functional result and no local soft tissue irritation or implant removal.

Femoral neck fracture after removal of the compression hip screw from healed intertrochanteric fractures

OBJECTIVES

To evaluate the incidence of femoral neck fracture (FNF) after removal of a compression hip screw (CHS) without trauma and to determine the risk factors for this type of fracture.

DESIGN

Retrospective study of consecutive patient series.

SETTING

University teaching hospital.

PATIENTS

Sixty-seven patients with a mean age of 65.3 years (45 women and 22 men).

INTERVENTION

A total of 67 implants were removed in the presence of bony consolidation of the fracture site; most of them were due to hardware pain.

MAIN OUTCOME MEASURES

The incidence of FNF after a CHS removal, clinical parameters (age, gender, bone mineral density, body mass index, and fracture stability), and radiologic parameters (the femoral neck-shaft angle, femoral neck width, distance between thread of lag screw, and neck cortex). Univariate analysis was performed for those parameters of the fracture group and the nonfracture group. To assess which variables were associated with FNF, a multiple logistic regression was used.

RESULTS

Six (9.0%) FNFs occurred within 1 month after a CHS removal. The mean anterior and lateral neck widths were significantly smaller, and the mean anterior and inferior thread-to-cortex distances were significantly shorter in the fracture group compared with the nonfracture group. The risk factor significantly associated with FNF was the inferior thread-to-cortex distance (odds ratio, 0.462; 95% confidence interval, 0.217-0.988).

CONCLUSIONS

CHS should not be removed routinely due to the risk of FNF. Furthermore, attention should be paid to at-risk patients with a hip screw positioned close to the inferior femoral neck cortex.

LEVEL OF EVIDENCE

Prognostic level II.