Targeted muscle reinnervation following external hemipelvectomy or hip disarticulation: An anatomic description of technique and clinical case correlates.

BACKGROUND: Targeted muscle reinnervation (TMR) has been shown to decrease or prevent neuropathic pain, including phantom and residual limb pain, after extremity amputation. Currently, a paucity of data and lack of anatomical description exists regarding TMR in the setting of hemipelvectomy and/or hip disarticulations. We elaborate on the technique of TMR, illustrated through cadaveric and clinical correlates. METHODS: Cadaveric dissections of multiple transpelvic exposures were performed. The major mixed motor and sensory nerve branches were identified, dissected, and tagged. Amputated peripheral nerves were transferred to identified, labeled target motor nerves via direct end-to-end nerve coaptations per traditional TMR technique. A retrospective review was completed by our multi-institutional teams to include examples of clinical correlates for TMR performed in the setting of hemipelvectomies and hip disarticulations. RESULTS: A total of 12 TMR hemipelvectomy/hip disarticulation cases were performed over a 2 to 3-year period (2018-2020). Of these 12 cases, 9 were oncologic in nature, 2 were secondary to traumatic injury, and 1 was a failed limb salvage in the setting of chronic refractory osteomyelitis of the femoral shaft. CONCLUSIONS: This manuscript outlines the technical considerations for TMR in the setting of hemipelvectomy and hip disarticulation with supporting clinical case correlates.

Current concepts review: Management of civilian transpelvic gunshot fractures.

INTRODUCTION: Civilian gunshot fractures of the pelvic ring represent a unique challenge for orthopaedic surgeons due to a high incidence of complicating associated injuries. Internationally accepted guidelines for these injuries are not available. The aim of this review is to summarize the available literature and to provide concise management recommendations. METHODS: Literature search was performed using PubMed. The review focuses on civilian gunshot fractures of the pelvic ring and includes the acetabulum and hip joint only where it was deemed necessary for the understanding of the management of these patients. RESULTS: The management of civilian transpelvic gunshot fractures is complicated by potentially life-threatening associated injuries, the risk of contamination with bowel content and retained bullets in joints. The infection risk is higher compared to extremity gunshot fractures. There is no clear evidence for the use of antibiotics available. The studies focusing on civilian pelvic ring gunshot fractures reported no case of orthopaedic fracture fixation in their series. Routine wash-out and debridement of fractures is not warranted based on the literature but conflicting recommendations for surgical interventions exist. CONCLUSION: There is limited evidence available for civilian transpelvic gunshot fractures. The high frequency of associated injuries requires a thorough clinical examination and multidisciplinary management. We recommend routine antibiotic prophylaxis for all transpelvic gunshots. For fractures with a high risk of infection, a minimum of 24 h broad-spectrum antibiotics is recommended. The indication for orthopaedic fixation of civilian transpelvic gunshot fractures is based on the assessment of the stability of the fracture and is rarely necessary. Although conflicting recommendations exist, routine wash-out and debridement is not recommended based on the literature. Bullets buried in bone without contact to synovial fluid do not warrant removal, unless they have traversed large bowel and are accessible without undue morbidity. Furthermore, bullets should be routinely removed if they are retained in the hip joint, if mechanical irritation of soft tissues by projectiles is expected or if the bullet traversed large bowel before entering the hip joint.

Comparison of urethral length and orifice diameter in cats undergoing transpelvic or subpubic urethrostomy for perineal urethrostomy revision (cadaveric study).

OBJECTIVES: Stenosis is a postoperative complication reported in 12-17% of male cats that undergo perineal urethrostomy (PU). This study compared two different revision techniques for failed perineal urethrostomies. The first objective was to evaluate the feasibility of performing a transpelvic urethrostomy (TPU) after a previous, correctly performed PU in male cats. The second objective was to determine the residual urethral length, orifice diameter, and the position of the orifice relative to the pubic brim and anus after PU, TPU and subpubic urethrostomy (SPU). METHODS: Twenty male cat cadavers were randomly divided into two groups: TPU and SPU. In group TPU, PU was followed by TPU; in group SPU, PU was followed by SPU. After each procedure, the urethral orifice cross-section size was estimated by inserting the largest possible urinary catheter without resistance. Residual urethral length was measured both on contrast radiographs and after anatomical dissection. RESULTS: In all cats, TPU could be performed following a technically correct PU. The TPU resulted in a 1.5-times longer residual urethral length than SPU, based on contrast radiographs (P = 0.001) and confirmed by anatomical dissection (P <0.001). Relative to the initial urethral length, PU, TPU and SPU resulted in a reduction of 24%, 36% and 56%, respectively. The urethral orifice diameter after TPU did not differ from SPU (P = 1.000), and it was not statistically significantly different between TPU and PU (P = 0.317) or between SPU and PU (P = 0.655). The urethral orifice was located further away from the pubis (P <0.001) and closer to the anus (P <0.001) after TPU than after SPU. CONCLUSIONS AND RELEVANCE: Both TPU and SPU are possible revision surgeries following PU. As TPU preserves a significantly longer urethral length and requires less tissue dissection, the risk of urinary tract infections, urinary dermatitis and urinary incontinence might be less following TPU than SPU.

Medullary pyramid thickness: The optimal cut-off value associated with the need for pyeloplasty in infants.

INTRODUCTION: The medullary pyramid compresses during the early phases of severe hydronephrosis and represents a promising ultrasound metric for the diagnosis and surveillance of PUJ obstruction. The aim of this study was to define the optimal cut-off value and utility of medullary pyramid thickness (MPT) associated with the need for pyeloplasty in infants being followed up for hydronephrosis. METHODS: A retrospective review was performed over a five-year period to identify patients that were under surveillance for hydronephrosis during infancy and underwent a MAG3 to monitor the possible need for pyeloplasty. Ultrasound images were retrospectively reviewed to measure the MPT of the affected kidney in a blinded fashion. The primary outcome measure was subsequent requirement for pyeloplasty before three years of age. The Mann-Whitney U Test was used to determine statistically significant differences in the minimum MPT between the infant group requiring pyeloplasty and the non-operative group. Receiver operating characteristic analysis was performed to determine the optimal cut-off value associated with the requirement for pyeloplasty. RESULTS: A total of 63 patient cases were included, of which 45 underwent pyeloplasty (70%). A significant difference was found in the median MPT measurement between the pyeloplasty and non-operative groups (1.7 mm vs. 3.8 mm, p < 0.001). The optimal cut-off value of MPT associated with pyeloplasty was 3.4 mm. An MPT threshold of ≤3.4 mm conferred a sensitivity of 98%, specificity of 63%, positive predictive value of 86%, and negative predictive value of 92%. CONCLUSION: Thinning of the medullary pyramid is an important ultrasound sign of parenchymal deterioration in high-grade hydronephrosis. An optimal MPT cut-off value of ≤3.4 mm is associated with subsequent pyeloplasty in infants. MPT should be considered in future studies addressing the diagnosis and surveillance of PUJ obstruction.

Outcomes and postoperative complications after transpelvic urethrostomy used as first-line surgery in 38 male cats with obstructive lower urinary tract disease.

OBJECTIVES: This article aimed to report on the short- and long-term outcomes after transpelvic urethrostomy (TPU) as a first-line surgery to treat obstructive lower urinary tract disease (OLUTD) in male cats. METHODS: A retrospective review and follow-up owner telephone questionnaire for cats with OLUTD undergoing TPU as a first-line surgery between 2013 and 2019, at a single referral hospital, were performed. A minimum follow-up period of 1 year was required to be included in the study. Short- and long-term complications were defined as those that occurred, respectively, within or after the first 4 weeks postoperatively. RESULTS: Thirty-eight male cats were included. The short-term complication rate was 18%. Idiopathic lower urinary tract disease (ILUTD) and stomal stenosis (SS) were the two most frequent short-term complications. Long-term complications were reported in 34% of the cats and included ILUTD, urinary tract infection and SS. The mortality rate was 5%. Eighty-two percent of the owners were satisfied with the postoperative outcome. The most common reason for owner dissatisfaction was the occurrence of SS, especially because these complications required multiple surgical revisions to be definitively managed. The long-term quality of life was considered to be good to very good by 89% of the owners. Ninety-one percent of the cats were free of clinical urinary signs at the time of the questionnaire completion. CONCLUSIONS AND RELEVANCE: TPU can be an acceptable first-line surgical technique to treat cats with OLUTD. Most cats experienced a good to very good quality of life after TPU. Most complications were transient or manageable medically. Most of the major complications were SS, which can be technically challenging to address and may require multiple revision surgeries.

Calyx to Parenchymal Ratio (CPR): An unexplored tool and its utility in the follow-up of pyeloplasty.

INTRODUCTION: Antero-posterior trans pelvic diameter (APD) and renal scintigraphy play a significant role in the diagnosis of pelvi-ureteric junction (PUJ) obstruction and postoperative follow-up following pyeloplasty. However, the APD varies irrespective of improvement, deterioration, or preserved function in a hydronephrotic kidney and is not a reliable parameter due to various factors (hydration status, compliance, and reduction pyeloplasty). Calyx to Parenchymal Ratio (CPR) is the ratio of the depth of the calyx and parenchymal thickness measured on ultrasound (USG) in coronal image. We assessed the utility of CPR in the follow up of pyeloplasty and compared it with the commonly used APD of the pelvis and renal scintigraphy. MATERIAL AND METHODS: A prospective cohort study was done from July 2016 to October 2017. During this period 73 pyeloplasties were done, and 62 cases meeting the inclusion criteria were enrolled. All the children underwent ultrasound and Technetium-99 m Ethylene dicysteine isotope renogram (EC) scan before and after pyeloplasty. APD and CPR values were measured on USG and compared with isotope renogram outcomes in these children in the preoperative versus postoperative period. Two defined objective variables ΔAPD, percent ΔAPD and ΔCPR, percent ΔCPR were compared with categorical variables that would predict the surgical outcome as - failed, successful or equivocal. Multinomial logistic regression analysis and receiver operating curve (ROC) analysis was used to identify predictive accuracy. RESULTS: The mean (range) APD value recorded in the preoperative period was 3.67 cm (1.40-8.00 cm), which decreased to 1.67 cm (0.40-6.50) postoperatively, which was 54.2% lower (P=<0.001). The mean (range) CPR value decreased from 5.96 (1.20-20.00) in the preoperative period to 2.57 (0.43-10.90) postoperatively, which was 56.8% lower (P=<0.001). On multinomial logistic regression analysis, ΔCPR was found to be a significant predictor of outcome with an overall accuracy of 95.1%, change in CPR was a better predictor of success after pyeloplasty as compared to change in APD, which had an overall accuracy of 85.2% (p = 0.01). Further, on ROC curve analysis, we observed that ΔCPR and %ΔCPR can strongly predict successful pyeloplasty with a sensitivity of each with 96% and 98% respectively and AUC of 0.897 and 0.799 respectively. DISCUSSION: USG (APD) and renogram are the most widely used investigation in follow-up of pyeloplasty; however, APD has its own limitations like operator variability and slower improvement. CPR has the advantages that neither calyceal depth nor parenchymal thickness is directly altered during the surgery, and early resolution of calyceal dilatation and rapid parenchymal growth following pyeloplasty and thus a surgeon independent parameter. Our results have shown that ΔCPR can identify successful pyeloplasty with strong prediction than ΔAPD and thus renal scans can be avoided if there is visible improvement in CPR on follow-up. CONCLUSIONS: Our study identified a change in CPR, i.e., ΔCPR as a strong predictor of surgical outcome, as it is not influenced by extent of pelvis reduction during pyeloplasty and early to change. Using this parameter, we can avoid unnecessary repeated nuclear scans based on persistent high APD values and optimize resource utilization. We recommend the use of CPR in routine practice in the preoperative and postoperative follow-up of PUJ obstruction following pyeloplasty.

Interdisciplinary Surgical Approaches in Vaginal and Perineal Reconstruction of Advanced Rectal and Anal Female Cancer Patients.

Relapsing or far advanced rectal and anal cancers remain difficult to treat and require interdisciplinary approaches. Due to modern standard protocols all patients receive irradiation and neoadjuvant chemotherapy-and in case of a relapse a second irradiation-rendering the surgical site prone to surgical site infections and oftentimes long lasting sinus and septic complications after exenteration in the pelvis. Despite an improved overall survival rate in these patients the downside of radical tumor surgery in the pelvis is a major loss of quality of life, especially in women when parts of the vagina need to be resected. Derived from our experince with over 300 patients receiving pelvic and perineal reconstruciton with a transpelvic vertical rectus abdominis myocutaneous (tpVRAM) flap we studied the impact of this surgical technique on the outcomes of female patients with or without vaginal reconstruction following pelvic exenteration. We found out that the tpVRAM flap is reliably perfused and helps to reduce long term wound healing desasters in the irradiated perineal/vaginal/gluteal region.

Free fillet lower leg flap for coverage after hemipelvectomy or hip disarticulation.

INTRODUCTION: Tumor resection is the gold standard treatment for soft tissue and bone sarcomas. In the pelvis, this may require a hemipelvectomy that can compromise primary skin closure. Flaps are essential in this context; however the vascularization of potential pedicled flaps may have been removed during tumor excision. Using healthy tissue from the amputated limb as a free flap is an excellent coverage option. HYPOTHESIS: The free fillet flap from an amputated lower limb is a simple and reliable coverage technique after hemipelvectomy or hip disarticulation. MATERIAL AND METHODS: Seven patients were operated on at three specialty centers: six transpelvic amputations (external hemipelvectomy) and one hip disarticulation. In three cases, the flap consisted of the superficial posterior compartment of the calf area and in the three other cases, the lower leg compartments with the fibula and its intact periosteum. Complications were documented. RESULTS: Clear resection margins were achieved in all patients. The mean follow-up at the final visit was 13 months (range, 6.5 to 21 months). Six patients had complications but only one resulted in loss of the flap. Four patients were able to be fitted with a hip prosthesis. DISCUSSION: The free fillet flap from an amputated lower limb is a reliable coverage technique (86%) after hemipelvectomy or hip disarticulation. In the 16 cases previously reported in the literature, there were no wound-healing failures. Local flaps are often too fragile with insufficient muscular padding. This free flap is the preferred first-line technique as it spares other potential free flaps in case of failure without increasing the morbidity of a procedure that is already extensive. This coverage technique should be one the options considered after external hemipelvectomy. LEVEL OF EVIDENCE: IV, retrospective study.

An unusual case of transpelvic impalement injury: A case-report.

INTRODUCTION: Impalement injury is a rare type of mechanical injury following forceful insertion of projecting object into the body. Careful planning for removal of the impaling object is essential to decrease the blood loss and preserve the function of the injured organ. PRESENTATION OF CASE: A 27 year-old male fell from 4m height over a U shaped projecting up metallic bar. The bar penetrated the left side of the pelvis and traversed through the left iliac bone causing a comminuted fracture in the supra-acetabular region extending to the left psoas muscle, injuring the viscera and causing fracture of the right femur. Exploratory laparotomy was performed and the metallic bar was pulled out from the sigmoid colon through the inlet of the injury. Intramedullary nailing was performed for femur fracture. The patient developed infection (Methicillin-sensitive Staphylococcus aureus and Escherichia coli) during the post-operative course that was successfully managed with antibiotic therapy. Finally the patient was sent home after a week in a good health condition. DISCUSSION: Two surgical teams worked in sequence to fix the injuries starting with the trauma team followed by the orthopedic surgeons. CONCLUSION: Impalement injury is a serious injury that needs a multidisciplinary team with a coordinated approach to achieve a favorable outcome.