Factors Related to Neuropathic Pain following Lower Extremity Amputation.

BACKGROUND: Lower extremity amputations are common, and postoperative neuropathic pain (phantom limb pain or symptomatic neuroma) is frequently reported. The use of active treatment of the nerve end has been shown to reduce pain but requires additional resources and should therefore be performed primarily in high-risk patients. The aim of this study was to identify the factors associated with the development of neuropathic pain following above-the-knee amputation, knee disarticulation, or below-the-knee amputation. METHODS: Retrospectively, 1565 patients with an average follow-up of 4.3 years who underwent a primary above-the-knee amputation, knee disarticulation, or below-the-knee amputation were identified. Amputation levels for above-the-knee amputations and knee disarticulations were combined as proximal amputation level, with below-the-knee amputations being performed in 61 percent of patients. The primary outcome was neuropathic pain (i.e., phantom limb pain or symptomatic neuroma) based on medical chart review. Multivariable logistic regression was performed to identify independent factors associated with neuropathic pain. RESULTS: Postoperative neuropathic pain was present in 584 patients (37 percent), with phantom limb pain occurring in 34 percent of patients and symptomatic neuromas occurring in 3.8 percent of patients. Proximal amputation level, normal creatinine levels, and a history of psychiatric disease were associated with neuropathic pain. Diabetes, hypothyroidism, and older age were associated with lower odds of developing neuropathic pain. CONCLUSIONS: Neuropathic pain following lower extremity amputation is common. Factors influencing nerve regeneration, either increasing (proximal amputations and younger age) or decreasing (diabetes, hypothyroidism, and chronic kidney disease) it, play a role in the development of postamputation neuropathic pain. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Quality of MIS vs Open Joint Preparations of the Foot and Ankle.

BACKGROUND: Minimally invasive surgery (MIS) is growing in the field of foot and ankle, and the MIS burr is an emerging tool. Although commonly used to perform osteotomies, the burr can also be used for arthrodesis joint preparation that traditionally would be performed through open incisions. To date, there is no study comparing the quality of joint preparation between using a fluoroscopy-guided MIS technique compared to traditional open techniques. The goal of this cadaveric study is to compare the percentage of joint surfaces prepared between MIS and open techniques for the most common joints that are fused in foot and ankle surgery. METHODS: Open joint preparation was performed under direct visualization with open incisions. MIS joint preparation was performed percutaneously using fluoroscopic guidance alone, without arthroscopy. After joint preparation, cadaveric samples were disarticulated, and joint surfaces were analyzed for percentage of cartilaginous surface removed. The percentage of joint surface prepared was compared between the open and MIS techniques. RESULTS: Ten cadaveric samples were used for the MIS technique and 5 samples for the open technique. Percentage of joint surface prepared was similar for all joint surfaces. CONCLUSION: The MIS technique in the hands of experienced surgeons was found to provide overall similar percentages of surface area prepared compared to traditional open techniques. CLINICAL RELEVANCE: MIS joint preparation may be useful for specific patient populations. This study suggests that MIS joint preparation is a reasonable, and possibly advantageous, alternative to open preparation in arthrodesis surgery when performed by experienced MIS surgeons.

A Limited Fixation, Olecranon Sparing Approach, for Management of Geriatric Intra-Articular Distal Humerus Fractures.

PURPOSE: We propose that geriatric comminuted intra-articular distal humerus fractures can be effectively treated with a limited fixation approach aimed at achieving varus/valgus stability with columnar fixation, but allowing intra-articular comminution to heal by secondary congruency against an intact olecranon, thus avoiding an olecranon osteotomy. METHODS: Fifty-six elderly patients with AO 13-C type fractures, who underwent surgical fixation with ≥12-months of follow-up were retrospectively reviewed. Thirty patients were treated with intra-articular open reduction internal fixation (ORIF) with an olecranon osteotomy and 26 patients were treated with our limited fixation (L-ORIF) approach. Outcomes were range of motion (ROM), complications, additional surgery, and patient-reported outcome measures (PROMIS). RESULTS: At final follow-up, the average elbow ROM was 97° (40°-155°) in the ORIF group and 86.5° (20°-145°) in the L-ORIF group. There was a trend toward more complications and additional surgery in the ORIF group. PROMIS scores for pain were 53.1 and 52.14, and PROMIS functional scores were 41.7 and 41.4 in the ORIF and L-ORIF group respectively. No differences in outcomes were statistically significant. CONCLUSION: A limited fixation technique based on achieving varus/valgus stability with columnar fixation, demonstrated equivalent outcomes in elderly patients with intra-articular distal humerus fractures when compared to intra-articular ORIF with an olecranon osteotomy.

Getting the Starting Point Right: Prevention of Skiving and Fibular Cortical Breach During Suture Button Placement for Syndesmotic Ankle Injuries.

The use of suture button (SB) devices in the treatment of syndesmotic ankle injuries is increasing. These constructs have demonstrated better syndesmotic reduction, improved clinical outcomes, and lower rates of hardware removal compared with screw fixation. However, placing a SB device without a fibular plate can be technically challenging. In this technique tip, we use an illustrative case to demonstrate a technique tip that minimizes the risk of anterior or posterior cortical breach of the fibula and helps facilitate more accurate placement of a SB device.Levels of Evidence: Level V: Expert opinion.

Implant Removal Matrix for the upper Extremity Orthopedic Surgeon.

Orthopedic implant removal is a commonly performed procedure. While implant removal can be associated with improved symptoms, risks of the surgery are notable. Stripped screws, broken and retained hardware, and morbidity associated with soft tissue compromise during difficult removal are all common. Familiarity with the instruments is critical to procedure success. The purpose of this study is to assist removal of unfamiliar screws in upper extremity surgery by offering a reference for screw and driver compatibility across manufacturers. Inclusion of device manufacturers was determined by market share. Screw size, drive configuration, and screw removal system compatibility data was collected and recorded. Screw, guide-wire, and screwdriver compatibility was assessed and compared to two commonly utilized universal implant-removal sets. Eight upper extremity implant vendors were included. The data was compiled in table format according to manufacturer and sub-categorized to facilitate screw identification according to radiographically identifiable characteristics. The diversity of orthopaedic implants in upper extremity surgery requires careful preoperative planning to identify the appropriate equipment for implant removal. The goal of this work is to provide a centralized reference of commonly implanted screws, guide-wires, and drivers for the upper extremity to facilitate removal.

Complete Cuboid Dislocation With Associated Lisfranc Injury: A Case Report and Review of the Literature.

Cuboid dislocations are rare midfoot injuries that usually occur in the setting of high-energy trauma. Diagnosis can be challenging and optimal treatment remains unknown. This case report and review aims to summarize the recent literature on this topic.

Correlation of Soft Tissue Swelling and Timing to Surgery With Acute Wound Complications for Operatively Treated Ankle and Other Lower Extremity Fractures.

BACKGROUND: Considerable debate exists regarding how soft-tissue edema should influence timing of surgery for ankle and other lower extremity fractures. Assessment of swelling is subjective, and timing varies among surgeons. However, timing of surgery is one of the few modifiable factors in fracture care. Ultrasonography can objectively measure swelling and help determine optimal timing. The purposes of this study were to determine whether objective measures of swelling, timing to surgery, and patient-specific risk factors correlated with wound complications and to try to create a prediction model for postoperative wound complications based on identified modifiable and nonmodifiable risk factors. METHODS: Patients with closed ankle and other lower extremity fractures requiring surgery with an uninjured, contralateral extremity were included. Demographic information and sonographic measurements on both lower extremities were obtained pre-operatively. Subjects were followed for 3 months and wound complications were documented. A predictive algorithm of independent risk factors was constructed, determining wound complication risk. Given that patients with ankle fractures made up the majority of the study cohort (75/93 or 80%), a separate statistical analysis was performed on this group. A total of 93 subjects completed the study, with 75/93 sustaining ankle fractures. RESULTS: Overall wound complication rate was 18.3%. Timing to surgery showed no correlation with wound complications. A heel-pad edema index >1.4 was independently associated with wound complications. Subgroup analysis of ankle fractures demonstrated a 3.4× increase in wound complications with a heel-pad edema index >1.4. Tobacco history and BMI >25 were independent predictors of wound complications. An algorithm was established based on heel-pad edema index, BMI >25, and tobacco history. Patients with none of the 3 factors had a 3% probability of a wound complication. Patients with 1/3, 2/3 and 3/3 factors had a 12-36%, 60-86% and 96% probability of a wound complication, respectively. CONCLUSIONS: Timing to surgery had no correlation with wound complications. Heel-pad edema index >1.4, BMI >25, and tobacco-use correlated with wound complications. When separately analyzing the cohort that sustained ankle fractures, the heel-pad edema index of >1.4 was still demonstrated to be predictive of wound complications corresponding to a 3.4× increase in wound complication rates (11.1% vs 37.5%). Risk of wound complications significantly increased with each factor. In patients with increased BMI and/or tobacco use, resolution of heel edema may significantly reduce wound complications in lower extremity trauma. LEVEL OF EVIDENCE: Level II, prognostic, prospective cohort study.

A Compatibility Guide for the Orthopaedic Surgeon Planning to Perform Hardware Removal Surgery.

BACKGROUND: Removal of previously placed orthopaedic implants is a commonly performed procedure worldwide. Given the diversity of orthopaedic implant manufacturers, surgeons may be uncertain whether they have the appropriate screwdriver on site. The purpose of this study was to assess the compatibility of screw head and size configurations from various orthopaedic manufacturers with two commonly used universal screw removal sets. METHODS: Inclusion of orthopaedic implant manufacturers was determined by market share based on industry-monitoring financial firms. Screw size and drive type for the top grossing orthopaedic implant manufacturers were collected and recorded. Screw and screwdriver compatibility was assessed and compared with two commonly used universal screw removal sets. RESULTS: In total, six orthopaedic implant companies with commonly implanted screws throughout the appendicular skeleton were included. The data were compiled in table format with noncannulated, cannulated, and locking screw offerings separated by the screw size and manufacturer. Guidewire size compatibility for cannulated offerings was also assessed. CONCLUSIONS: Given the ubiquity of implanted orthopaedic implant, removal must be as safe, planned, and controlled as possible. The data in this article provide an inclusive, centralized resource for surgeons looking to confirm the compatibility of previously implanted screws and available removal equipment at their institution.

Implant Removal Matrix for the Foot and Ankle Orthopaedic Surgeon.

BACKGROUND: Orthopaedic surgery frequently requires the use of metal plate and screw constructs for osteosynthesis. These constructs may be subsequently removed for a variety of indications. In the lower extremity in particular, implants (ie, hardware) can lead to prominence and pain secondary to a thin soft-tissue envelope with little subcutaneous tissue. Often, removal is performed without knowledge of the exact type of screw head configuration and/or size, which can make removal technically challenging. The purpose of this study is to consolidate screw head sizes and configurations from commonly utilized orthopaedic foot and ankle implant manufacturers matched against 2 commonly used universal implant removal sets to aid in the expeditious removal of hardware. METHODS: Orthopaedic manufacturers of foot and ankle-specific implants were included based on market share. Publicly available information on screw size, head configuration, and driver size was collected and recorded. This information was cross-referenced against the drivers available in 2 commonly utilized universal implant removal sets. RESULTS: Seven foot and ankle implant manufacturers were included. The data were compiled in table format according to manufacturer and subcategorized by noncannulated screws, cannulated screws, and locking screws. CONCLUSION: Many factors affect the success of hardware removal, and it is imperative that the surgeon knows which drivers are compatible with the implanted hardware. The expanding magnitude and diversity of orthopaedic implants makes removal of hardware more challenging. A guide of compatible drivers for various screw types helps expedite this procedure. LEVELS OF EVIDENCE: Level V.

CA-074Me compound inhibits osteoclastogenesis via suppression of the NFATc1 and c-FOS signaling pathways.

The osteoclast is an integral cell of bone resorption. Since osteolytic disorders hinge on the function and dysfunction of the osteoclast, understanding osteoclast biology is fundamental to designing new therapies that curb osteolytic disorders. The identification and study of lysosomal proteases, such as cathepsins, have shed light on mechanisms of bone resorption. For example, Cathepsin K has already been identified as a collagen degradation protease produced by mature osteoclasts with high activity in the acidic osteoclast resorption pits. Delving into the mechanisms of cathepsins and other osteoclast related compounds provides new targets to explore in osteoclast biology. Through our anti-osteoclastogenic compound screening experiments we encountered a modified version of the Cathepsin B inhibitor CA-074: the cell membrane-permeable CA-074Me (L-3-trans-(Propylcarbamoyl) oxirane-2-carbonyl]-L-isoleucyl-L-proline Methyl Ester). Here we confirm that CA-074Me inhibits osteoclastogenesis in vivo and in vitro in a dose-dependent manner. However, Cathepsin B knockout mice exhibited unaltered osteoclastogenesis, suggesting a more complicated mechanism of action than Cathepsin B inhibition. We found that CA-074Me exerts its osteoclastogenic effect within 24 h of osteoclastogenesis stimulation by suppression of c-FOS and NFATc1 pathways.