Pronator Quadratus Muscle Flap for Prevention of Flexor Tendon Rupture after Distal Radius Volar Plating

Background

Flexor tendon rupture is a serious but rare complication that can occur after volar plating of distal radius fractures. This study aims to introduce a novel surgical technique that uses a pronator quadratus (PQ) muscle flap transposition to protect the flexor tendons from rupture or irritation and evaluate its outcomes.

Methods

A retrospective review was conducted on 204 patients with unstable distal radius fractures who underwent a standard volar flexor carpi radialis approach with extended release of the PQ muscle during exposure. A PQ muscle flap was harvested and transposed over the distal edge of the plate after open reduction and internal fixation of the distal radius. Postoperatively, patients were evaluated for flexor tendon irritation and rupture. Patients who had this injury before the use of the PQ flap were compared with the patients who received the PQ flap.

Results

Of the 204 patients, 119 received the PQ flap, and 85 did not. The mean follow-up time was 30.4 months. Among the patients who did not receive the PQ flap, five (5.9%) required plate removal or conservative treatment for tendon irritation or rupture. In contrast, only one patient (0.8%) who received the PQ flap required plate removal for flexor tendon irritation.

Conclusions

The PQ muscle flap is a quick and effective surgical technique that reduces the risk of flexor tendon rupture or irritation during distal radius fracture fixation. The PQ muscle flap acts as a buffer between the plate and tendon and is more effective than not transposing the muscle.

A characterization of home maintenance equipment-related hand and lower arm injuries

BACKGROUND

Thousands of Americans sustain injuries from various household appliances each year, though injury patterns have not been well characterized. We thus sought to determine the incidence, characteristics, and trends of household appliance-related hand injuries over the past decade.

METHODS

The National Electronic Injury Surveillance System database (NEISS) was queried from 2010 through 2019. Our analysis grouped patients into 10-year age groups. We defined types of appliances and injuries Chi-square tests were used to compare the most common injury mechanisms by age group.

RESULTS

Between 2010 and 2019, 30,336 total cases of home workshop equipment-related upper extremity injuries were recorded; 2,574 (8.48%) of these affected females, compared to 27,762 (91.52%) of the cases affecting males. Across all age groups, males were between 6 and 13 more times likely to be injured than females (p < 0.001). Between 2010 and 2019, we recorded a decline in total injuries from 168,795 to 147,584, with a Pearson correlation coefficient of -0.68 (p = 0.031). The appliances most likely to injure those in their 10s through 40s were mechanical tools such as screwdrivers. Meanwhile, those in their 50s through 70s were most likely to be injured by saws. Both amputations and avulsions were found to significantly increase with age (p = 0.038, p = 0.027, respectively). Most injuries result from manual tools and saws.

DISCUSSION

Males are significantly more likely to incur injuries than females from maintenance equipment, and risk of avulsions and amputations increase significantly with age. This aligns with previous research which also suggested that older saws were most likely to injure older individuals; namely, following new regulations on saws, older adults were more likely to be affected. This is especially worrisome in light of recent research showing that older adults with amputations are less likely to be offered replantations. Overall, these results can continue to guide and optimize community interventions on an epidemiological basis.

Comparison of human amniotic membrane and collagen nerve wraps around sciatic nerve reverse autografts in a rat model

Human amniotic membrane (hAM) and collagen nerve wraps are biomaterials that have been investigated as therapies for improving outcomes of peripheral nerve regeneration; however, their efficacy has not been compared. The purpose of this study is to compare the efficacy of collagen and human amniotic membrane nerve wraps in a rodent sciatic nerve reverse autograft model. Lewis rats (n = 29) underwent sciatic nerve injury and repair in which a 10-mm gap was bridged with reverse autograft combined with either no nerve wrap (control), collagen nerve wrap or hAM nerve wrap. Behavioral analyses were performed at baseline and 4, 8 and 12 weeks. Electrophysiological studies were conducted at 8, 10 and 12 weeks. Additional outcomes assessed included gastrocnemius muscle weights, nerve adhesions, axonal regeneration and scarring at 12 weeks. Application of both collagen and hAM nerve wraps resulted in improvement of functional and histologic outcomes when compared with controls, with a greater magnitude of improvement for the experimental group treated with hAM nerve wraps. hAM-treated animals had significantly higher numbers of axons compared to control animals (p < 0.05) and significantly less perineural fibrosis than both control and collagen treated nerves (p < 0.05). The ratio of experimental to control gastrocnemius weights was significantly greater in hAM compared to control samples (p < 0.05). We conclude that hAM nerve wraps are a promising biomaterial that is effective for improving outcomes of peripheral nerve regeneration, resulting in superior nerve regeneration and functional recovery compared to collagen nerve wraps and controls.

Comparison of Collagen and Human Amniotic Membrane Nerve Wraps and Conduits for Peripheral Nerve Repair in Preclinical Models: A Systematic Review of the Literature

INTRODUCTION

 Collagen and human amniotic membrane (hAM) are Food and Drug Administration (FDA)-approved biomaterials that can be used as nerve wraps or conduits for repair of peripheral nerve injuries. Both biomaterials have been shown to reduce scarring and fibrosis of injured peripheral nerves. However, comparative advantages and disadvantages have not been definitively shown in the literature. The purpose of this systematic review is to comprehensively evaluate the literature regarding the roles of hAM and collagen nerve wraps and conduits on peripheral nerve regeneration in preclinical models.

METHODS

 The MEDLINE database was queried using the PubMed search engine on July 7, 2019, with the following search strategy: ("amniotic membrane" OR "amnion") OR ("collagen conduit" OR "nerve wrap")] AND "nerve." All resulting articles were screened by two independent reviewers. Nerve type, lesion type/injury model, repair type, treatment, and outcomes were assessed.

RESULTS

 Two hundred and fifty-eight articles were identified, and 44 studies remained after application of inclusion and exclusion criteria. Seventeen studies utilized hAM, whereas 27 studies utilized collagen wraps or conduits. Twenty-three (85%) of the collagen studies utilized conduits, and four (15%) utilized wraps. Six (35%) of the hAM studies utilized conduits and 11 (65%) utilized wraps. Two (9%) collagen studies involving a conduit and one (25%) involving a wrap demonstrated at least one significant improvement in outcomes compared with a control. While none of the hAM conduit studies showed significant improvements, eight (73%) of the studies investigating hAM wraps showed at least one significant improvement in outcomes.

CONCLUSION

 The majority of studies reported positive outcomes, indicating that collagen and hAM nerve wraps and conduits both have the potential to enhance peripheral nerve regeneration. However, relatively few studies reported significant findings, except for studies evaluating hAM wraps. Preclinical models may help guide clinical practice regarding applications of these biomaterials in peripheral nerve repair.

Latissimus Dorsi Flap in Breast Reconstruction: Recent Innovations in the Workhorse Flap

Background:

Surgeons employ the latissimus dorsi flap (LDF) for reconstruction of a large variety of breast cancer surgery defects, including quadrantectomy, lumpectomy, modified radical mastectomy, and others. The LDF may be used in delayed or immediate reconstruction, in combination with tissue expanders for a staged reconstruction, with implant-based immediate reconstruction, or alone as an autogenous flap.

Methods:

The authors discuss the historical uses and more recent developments in the LDF. More recent advancements, including the “scarless” approach and augmentation with the thoracodorsal artery perforator flap, are discussed.

Results:

The LDF is a reliable means for soft tissue coverage providing form and function during breast reconstruction with acceptable perioperative and long-term morbidities.

Conclusions:

When there is a paucity of tissue, the LDF can provide tissue volume in autologous reconstruction, as well as a reliable vascular pedicle for implant-based reconstruction as in the setting of irradiated tissue.

The Relationship of Bacterial Biofilms and Capsular Contracture in Breast Implants

Capsular contracture is a common sequelae of implant-based breast augmentation. Despite its prevalence, the etiology of capsular contracture remains controversial. Numerous studies have identified microbial biofilms on various implantable materials, including breast implants. Furthermore, biofilms have been implicated in subclinical infections associated with other surgical implants. In this review, we discuss microbial biofilms as a potential etiology of capsular contracture. The review also outlines the key diagnostic modalities available to identify the possible infectious agents found in biofilm, as well as available preventative and treatment measures.

Merkel cell carcinoma of the hand and upper extremity: current trends and outcomes

Merkel cell carcinomas represent an uncommon yet aggressive skin cancer. We sought to identify changes in incidence and predictors of outcomes and survival of patients with Merkel cell carcinomas of the hand and upper extremity. The Surveillance, Epidemiology and End Results database was used to identify all patients with Merkel cell carcinomas of the skin located specifically in the hand and upper extremity. Overall, 5211 cases were identified in the period from 1986 through 2009. The age-adjusted incidence of Merkel cell carcinoma of the hand and upper extremity increased from 0.02 cases per 100,000 in 1986 to 0.14 cases per 100,000 in 2009. The mean age of these patients was 75 years and positive regional lymph nodes were identified in 33%. Rate of metastasis was 4.1%. Overall survival for the study cohort was 49%. Multivariate analysis identified tumor size >5 cm, positive regional lymph nodes and metastasis at diagnosis as independent predictors of mortality. The incidence of Merkel cell carcinomas has increased substantially over the study period. Overall survival for Merkel cell carcinomas of the body and hand and upper extremity is related to tumor size and extent of disease at time of clinical presentation. Merkel cell carcinomas of the hand and upper extremity tend to be diagnosed at an earlier stage with lower rates of regional and systemic spread, and subsequently have a higher overall survival rate.

Trends in the surgical treatment of cubital tunnel syndrome: an analysis of the national survey of ambulatory surgery database

PURPOSE

To ascertain trends in the surgical treatment of ulnar nerve compression at the elbow within the United States.

METHODS

We analyzed the National Survey of Ambulatory Surgery to study trends in the treatment of cubital tunnel syndrome from 1994 to 2006. The National Survey of Ambulatory Surgery provides a comprehensive overview of ambulatory surgical procedures performed in the United States. Patients identified in the database with surgically treated cubital tunnel syndrome were verified by members of our research staff and compiled into these 3 groups: decompression, transposition, and other. The data were then statistically analyzed for trends in treatment, utilization, and demographics.

RESULTS

A total of 52,133 surgical procedures were recorded in the National Survey of Ambulatory Surgery for the treatment of ulnar nerve compression in 2006. This represents an increase from 26,283 in 1994 and 35,406 in 1996. In the 11 years from 1996 to 2006, the total surgical procedures on the ulnar nerve increased by 47%. Transposition went from 49% of all cubital tunnel procedures in the 1990s to 38% in 2006. In 2006, women were much more likely to have a simple decompression (70%) than a transposition or other technique. Decompression had a mean surgical time of 48 minutes, and transposition had a mean surgical time of 59 minutes.

CONCLUSIONS

The percentage of transpositions used in the treatment of cubital syndrome has decreased to 37% in the last survey. Possible reasons include expanded indications or changing surgical preferences.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic II.

Posttraumatic Mandibular Deformities

In covering the Emergency Department, the Plastic Surgeon can be faced with the mandibular fracture patient. Although the timely repair of the fracture usually leads to normal function and appearance, occasionally the surgeon is faced with the untoward sequelae of the mandible fracture. Post-traumatic mandibular deformities include non-union, malunion, malocclusion, TMJ dysfuction, and facial asymmetry. The difficulty in treatment of these deformities can be compounded by edentulous mandibles, substance abuse, and approach controversies such as the timing of the repair and surgical versus non-surgical management. Knowledge of the post-traumatic mandibular deformities by the treating physician not only assists in their management but may also allow for their prevention.

A Simple Method for the Control of Medicinal Leeches

The medicinal leech, Hirudo medicinalis, has been widely used in the salvage of microvascular free flaps. Numerous publications have detailed the biology, use, benefits, and risks of leech therapy. One reported significant risk is the risk of leech movement or migration from the surgical site, possibly into body orifices or even deeper into the wound itself. The authors report a simple method of limiting the movement of medicinal leeches from the surgical site, namely, affixing one end of a surgical suture to the leech and tying the free end to a firm object or dressing. This simple method limits the potential range of movement of the leech and reduces the risk of leech migration to unwanted areas.

Hand abnormalities associated with craniofacial syndromes

One in approximately every 626 newborns has a congenital anomaly of the upper limb. Frequently, patients with craniofacial syndromes may have associated hand anomalies. In this article, we try to answer why certain craniofacial syndromes have associated hand anomalies through an examination of the common factors in development and maldevelopment of these two very complex structures. In general, we conclude that the common factors responsible for patients with craniofacial syndromes that have associated hand anomalies are the common time course of development of these two structures and certain mutations of genes controlling limb and craniofacial development. This article attempts to elucidate the sequence and crucial factors responsible for proper limb growth, as we understand it today. The most common craniofacial syndromes that include craniosynostosis and upper extremity anomalies are presented. These are Apert's, Saethre-Chotzen, Pfeiffer's, and Carpenter's syndromes. As we discuss each of these syndromes, basic principles regarding the surgical correction of the associated hand anomalies are described. We hope that this overview serves to give the pediatrician and the craniofacial specialist general guidelines for what to look for and expect in the hands and upper extremities of children under their care.